Resguardo inicial

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_ddc.c

@@ -0,0 +1,702 @@
+/*
+ * Copyright 2012-15 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+/* FILE POLICY AND INTENDED USAGE:
+ *
+ * This file implements generic display communication protocols such as i2c, aux
+ * and scdc. The file should not contain any specific applications of these
+ * protocols such as display capability query, detection, or handshaking such as
+ * link training.
+ */
+#include "link_ddc.h"
+#include "link_hdmi_frl.h"
+#include "vector.h"
+#include "dce/dce_aux.h"
+#include "dal_asic_id.h"
+#include "link_dpcd.h"
+#include "dm_helpers.h"
+#include "atomfirmware.h"
+
+#define DC_LOGGER \
+	ddc_service->ctx->logger
+#define DC_LOGGER_INIT(logger)
+
+static const uint8_t DP_VGA_DONGLE_BRANCH_DEV_NAME[] = "DpVga";
+/* DP to Dual link DVI converter */
+static const uint8_t DP_DVI_CONVERTER_ID_4[] = "m2DVIa";
+static const uint8_t DP_DVI_CONVERTER_ID_5[] = "3393N2";
+
+struct i2c_payloads {
+	struct vector payloads;
+};
+
+static bool i2c_payloads_create(
+		struct dc_context *ctx,
+		struct i2c_payloads *payloads,
+		uint32_t count)
+{
+	if (dal_vector_construct(
+		&payloads->payloads, ctx, count, sizeof(struct i2c_payload)))
+		return true;
+
+	return false;
+}
+
+static struct i2c_payload *i2c_payloads_get(struct i2c_payloads *p)
+{
+	return (struct i2c_payload *)p->payloads.container;
+}
+
+static uint32_t i2c_payloads_get_count(struct i2c_payloads *p)
+{
+	return p->payloads.count;
+}
+
+static void i2c_payloads_destroy(struct i2c_payloads *p)
+{
+	if (!p)
+		return;
+
+	dal_vector_destruct(&p->payloads);
+}
+
+#define DDC_MIN(a, b) (((a) < (b)) ? (a) : (b))
+
+static void i2c_payloads_add(
+	struct i2c_payloads *payloads,
+	uint32_t address,
+	uint32_t len,
+	uint8_t *data,
+	bool write)
+{
+	uint32_t payload_size = EDID_SEGMENT_SIZE;
+	uint32_t pos;
+
+	for (pos = 0; pos < len; pos += payload_size) {
+		struct i2c_payload payload = {
+			.write = write,
+			.address = (uint8_t)address,
+			.length = DDC_MIN(payload_size, len - pos),
+			.data = data + pos };
+		dal_vector_append(&payloads->payloads, &payload);
+	}
+
+}
+
+static void ddc_service_construct(
+	struct ddc_service *ddc_service,
+	struct ddc_service_init_data *init_data)
+{
+	enum connector_id connector_id =
+		dal_graphics_object_id_get_connector_id(init_data->id);
+
+	struct gpio_service *gpio_service = init_data->ctx->gpio_service;
+	struct graphics_object_i2c_info i2c_info;
+	struct gpio_ddc_hw_info hw_info;
+	struct dc_bios *dcb = init_data->ctx->dc_bios;
+
+	ddc_service->link = init_data->link;
+	ddc_service->ctx = init_data->ctx;
+
+	if (ddc_service->link && ddc_service->ctx->dc->config.dp_connector_no_native_i2c &&
+		ddc_service->link->no_ddc_pin) {
+		// Obtain aux instance info from i2c_info without GPIO DDC pin info
+		if (dcb->funcs->get_connector_aux_info(dcb, init_data->id, &i2c_info) == BP_RESULT_OK)
+			ddc_service->link->aux_hw_inst = (uint8_t)i2c_info.i2c_line;
+	}  else {
+		if (init_data->is_dpia_link ||
+		dcb->funcs->get_i2c_info(dcb, init_data->id, &i2c_info) != BP_RESULT_OK) {
+			ddc_service->ddc_pin = NULL;
+		} else {
+			DC_LOGGER_INIT(ddc_service->ctx->logger);
+			DC_LOG_DC("BIOS object table - i2c_line: %d", i2c_info.i2c_line);
+			DC_LOG_DC("BIOS object table - i2c_engine_id: %d", i2c_info.i2c_engine_id);
+
+			hw_info.ddc_channel = i2c_info.i2c_line;
+			if (ddc_service->link != NULL)
+				hw_info.hw_supported = i2c_info.i2c_hw_assist;
+			else
+				hw_info.hw_supported = false;
+
+			ddc_service->ddc_pin = dal_gpio_create_ddc(
+				gpio_service,
+				i2c_info.gpio_info.clk_a_register_index,
+				1 << i2c_info.gpio_info.clk_a_shift,
+				&hw_info);
+		}
+	}
+
+	ddc_service->flags.EDID_QUERY_DONE_ONCE = false;
+	ddc_service->flags.FORCE_READ_REPEATED_START = false;
+	ddc_service->flags.EDID_STRESS_READ = false;
+
+	ddc_service->flags.IS_INTERNAL_DISPLAY =
+		connector_id == CONNECTOR_ID_EDP ||
+		connector_id == CONNECTOR_ID_LVDS;
+
+	ddc_service->wa.raw = 0;
+}
+
+struct ddc_service *link_create_ddc_service(
+	struct ddc_service_init_data *init_data)
+{
+	struct ddc_service *ddc_service;
+
+	ddc_service = kzalloc_obj(struct ddc_service);
+
+	if (!ddc_service)
+		return NULL;
+
+	ddc_service_construct(ddc_service, init_data);
+	return ddc_service;
+}
+
+static void ddc_service_destruct(struct ddc_service *ddc)
+{
+	if (ddc->ddc_pin)
+		dal_gpio_destroy_ddc(&ddc->ddc_pin);
+}
+
+void link_destroy_ddc_service(struct ddc_service **ddc)
+{
+	if (!ddc || !*ddc) {
+		BREAK_TO_DEBUGGER();
+		return;
+	}
+	ddc_service_destruct(*ddc);
+	kfree(*ddc);
+	*ddc = NULL;
+}
+
+void set_ddc_transaction_type(
+	struct ddc_service *ddc,
+	enum ddc_transaction_type type)
+{
+	ddc->transaction_type = type;
+}
+
+bool link_is_in_aux_transaction_mode(struct ddc_service *ddc)
+{
+	switch (ddc->transaction_type) {
+	case DDC_TRANSACTION_TYPE_I2C_OVER_AUX:
+	case DDC_TRANSACTION_TYPE_I2C_OVER_AUX_WITH_DEFER:
+	case DDC_TRANSACTION_TYPE_I2C_OVER_AUX_RETRY_DEFER:
+		return true;
+	default:
+		break;
+	}
+	return false;
+}
+
+void set_dongle_type(struct ddc_service *ddc,
+		enum display_dongle_type dongle_type)
+{
+	ddc->dongle_type = dongle_type;
+}
+
+static uint32_t defer_delay_converter_wa(
+	struct ddc_service *ddc,
+	uint32_t defer_delay)
+{
+	struct dc_link *link = ddc->link;
+
+	if (link->dpcd_caps.dongle_type == DISPLAY_DONGLE_DP_VGA_CONVERTER &&
+		link->dpcd_caps.branch_dev_id == DP_BRANCH_DEVICE_ID_0080E1 &&
+		(link->dpcd_caps.branch_fw_revision[0] < 0x01 ||
+				(link->dpcd_caps.branch_fw_revision[0] == 0x01 &&
+				link->dpcd_caps.branch_fw_revision[1] < 0x40)) &&
+		!memcmp(link->dpcd_caps.branch_dev_name,
+		    DP_VGA_DONGLE_BRANCH_DEV_NAME,
+			sizeof(link->dpcd_caps.branch_dev_name)))
+
+		return defer_delay > DPVGA_DONGLE_AUX_DEFER_WA_DELAY ?
+			defer_delay : DPVGA_DONGLE_AUX_DEFER_WA_DELAY;
+
+	if (link->dpcd_caps.branch_dev_id == DP_BRANCH_DEVICE_ID_0080E1 &&
+	    !memcmp(link->dpcd_caps.branch_dev_name,
+		    DP_DVI_CONVERTER_ID_4,
+		    sizeof(link->dpcd_caps.branch_dev_name)))
+		return defer_delay > I2C_OVER_AUX_DEFER_WA_DELAY ?
+			defer_delay : I2C_OVER_AUX_DEFER_WA_DELAY;
+	if (link->dpcd_caps.branch_dev_id == DP_BRANCH_DEVICE_ID_006037 &&
+	    !memcmp(link->dpcd_caps.branch_dev_name,
+		    DP_DVI_CONVERTER_ID_5,
+		    sizeof(link->dpcd_caps.branch_dev_name)))
+		return defer_delay > I2C_OVER_AUX_DEFER_WA_DELAY_1MS ?
+			I2C_OVER_AUX_DEFER_WA_DELAY_1MS : defer_delay;
+
+	return defer_delay;
+}
+
+#define DP_TRANSLATOR_DELAY 5
+
+uint32_t link_get_aux_defer_delay(struct ddc_service *ddc)
+{
+	uint32_t defer_delay = 0;
+
+	switch (ddc->transaction_type) {
+	case DDC_TRANSACTION_TYPE_I2C_OVER_AUX:
+		if ((DISPLAY_DONGLE_DP_VGA_CONVERTER == ddc->dongle_type) ||
+			(DISPLAY_DONGLE_DP_DVI_CONVERTER == ddc->dongle_type) ||
+			(DISPLAY_DONGLE_DP_HDMI_CONVERTER ==
+				ddc->dongle_type)) {
+
+			defer_delay = DP_TRANSLATOR_DELAY;
+
+			defer_delay =
+				defer_delay_converter_wa(ddc, defer_delay);
+
+		} else /*sink has a delay different from an Active Converter*/
+			defer_delay = 0;
+		break;
+	case DDC_TRANSACTION_TYPE_I2C_OVER_AUX_WITH_DEFER:
+		defer_delay = DP_TRANSLATOR_DELAY;
+		break;
+	default:
+		break;
+	}
+	return defer_delay;
+}
+
+static bool submit_aux_command(struct ddc_service *ddc,
+		struct aux_payload *payload)
+{
+	uint32_t retrieved = 0;
+	bool ret = false;
+
+	if (!ddc)
+		return false;
+
+	if (!payload)
+		return false;
+
+	do {
+		struct aux_payload current_payload;
+		bool is_end_of_payload = (retrieved + DEFAULT_AUX_MAX_DATA_SIZE) >=
+				payload->length;
+		uint32_t payload_length = is_end_of_payload ?
+				payload->length - retrieved : DEFAULT_AUX_MAX_DATA_SIZE;
+
+		current_payload.address = payload->address;
+		current_payload.data = &payload->data[retrieved];
+		current_payload.defer_delay = payload->defer_delay;
+		current_payload.i2c_over_aux = payload->i2c_over_aux;
+		current_payload.length = payload_length;
+		/* set mot (middle of transaction) to false if it is the last payload */
+		current_payload.mot = is_end_of_payload ? payload->mot:true;
+		current_payload.write_status_update = false;
+		current_payload.reply = payload->reply;
+		current_payload.write = payload->write;
+
+		ret = link_aux_transfer_with_retries_no_mutex(ddc, &current_payload);
+
+		retrieved += payload_length;
+	} while (retrieved < payload->length && ret == true);
+
+	return ret;
+}
+
+bool link_query_ddc_data(
+	struct ddc_service *ddc,
+	uint32_t address,
+	uint8_t *write_buf,
+	uint32_t write_size,
+	uint8_t *read_buf,
+	uint32_t read_size)
+{
+	bool success = true;
+	uint32_t payload_size =
+		link_is_in_aux_transaction_mode(ddc) ?
+			DEFAULT_AUX_MAX_DATA_SIZE : EDID_SEGMENT_SIZE;
+
+	uint32_t write_payloads =
+		(write_size + payload_size - 1) / payload_size;
+
+	uint32_t read_payloads =
+		(read_size + payload_size - 1) / payload_size;
+
+	uint32_t payloads_num = write_payloads + read_payloads;
+
+	if (!payloads_num)
+		return false;
+
+	if (link_is_in_aux_transaction_mode(ddc)) {
+		struct aux_payload payload;
+
+		payload.i2c_over_aux = true;
+		payload.address = address;
+		payload.reply = NULL;
+		payload.defer_delay = link_get_aux_defer_delay(ddc);
+		payload.write_status_update = false;
+
+		if (write_size != 0) {
+			payload.write = true;
+			/* should not set mot (middle of transaction) to 0
+			 * if there are pending read payloads
+			 */
+			payload.mot = !(read_size == 0);
+			payload.length = write_size;
+			payload.data = write_buf;
+
+			success = submit_aux_command(ddc, &payload);
+		}
+
+		if (read_size != 0 && success) {
+			payload.write = false;
+			/* should set mot (middle of transaction) to 0
+			 * since it is the last payload to send
+			 */
+			payload.mot = false;
+			payload.length = read_size;
+			payload.data = read_buf;
+
+			success = submit_aux_command(ddc, &payload);
+		}
+	} else {
+		struct i2c_command command = {0};
+		struct i2c_payloads payloads;
+
+		if (!i2c_payloads_create(ddc->ctx, &payloads, payloads_num))
+			return false;
+
+		command.payloads = i2c_payloads_get(&payloads);
+		command.number_of_payloads = 0;
+		command.engine = DDC_I2C_COMMAND_ENGINE;
+		command.speed = ddc->ctx->dc->caps.i2c_speed_in_khz;
+
+		i2c_payloads_add(
+			&payloads, address, write_size, write_buf, true);
+
+		i2c_payloads_add(
+			&payloads, address, read_size, read_buf, false);
+
+		command.number_of_payloads = (uint8_t)i2c_payloads_get_count(&payloads);
+
+		success = dm_helpers_submit_i2c(
+				ddc->ctx,
+				ddc->link,
+				&command);
+
+		i2c_payloads_destroy(&payloads);
+	}
+
+	return success;
+}
+
+int link_aux_transfer_raw(struct ddc_service *ddc,
+		struct aux_payload *payload,
+		enum aux_return_code_type *operation_result)
+{
+	return dce_aux_transfer_raw(ddc, payload, operation_result);
+}
+
+uint32_t link_get_fixed_vs_pe_retimer_write_address(struct dc_link *link)
+{
+	uint32_t vendor_lttpr_write_address = 0xF004F;
+	uint8_t offset;
+
+	switch (link->dpcd_caps.lttpr_caps.phy_repeater_cnt) {
+	case 0x80: // 1 lttpr repeater
+		offset =  1;
+		break;
+	case 0x40: // 2 lttpr repeaters
+		offset = 2;
+		break;
+	case 0x20: // 3 lttpr repeaters
+		offset = 3;
+		break;
+	case 0x10: // 4 lttpr repeaters
+		offset = 4;
+		break;
+	case 0x08: // 5 lttpr repeaters
+		offset = 5;
+		break;
+	case 0x04: // 6 lttpr repeaters
+		offset = 6;
+		break;
+	case 0x02: // 7 lttpr repeaters
+		offset = 7;
+		break;
+	case 0x01: // 8 lttpr repeaters
+		offset = 8;
+		break;
+	default:
+		offset = 0xFF;
+	}
+
+	if (offset != 0xFF) {
+		vendor_lttpr_write_address +=
+				((DP_REPEATER_CONFIGURATION_AND_STATUS_SIZE) * (offset - 1));
+	}
+	return vendor_lttpr_write_address;
+}
+
+uint32_t link_get_fixed_vs_pe_retimer_read_address(struct dc_link *link)
+{
+	return link_get_fixed_vs_pe_retimer_write_address(link) + 4;
+}
+
+bool link_configure_fixed_vs_pe_retimer(struct ddc_service *ddc, const uint8_t *data, uint32_t length)
+{
+	struct aux_payload write_payload = {
+		.i2c_over_aux = false,
+		.write = true,
+		.address = link_get_fixed_vs_pe_retimer_write_address(ddc->link),
+		.length = length,
+		.data = (uint8_t *) data,
+		.reply = NULL,
+		.mot = I2C_MOT_UNDEF,
+		.write_status_update = false,
+		.defer_delay = 0,
+	};
+
+	return link_aux_transfer_with_retries_no_mutex(ddc,
+			&write_payload);
+}
+
+bool link_query_fixed_vs_pe_retimer(struct ddc_service *ddc, uint8_t *data, uint32_t length)
+{
+	struct aux_payload read_payload = {
+		.i2c_over_aux = false,
+		.write = false,
+		.address = link_get_fixed_vs_pe_retimer_read_address(ddc->link),
+		.length = length,
+		.data = data,
+		.reply = NULL,
+		.mot = I2C_MOT_UNDEF,
+		.write_status_update = false,
+		.defer_delay = 0,
+	};
+
+	return link_aux_transfer_with_retries_no_mutex(ddc,
+			&read_payload);
+}
+
+bool link_aux_transfer_with_retries_no_mutex(struct ddc_service *ddc,
+		struct aux_payload *payload)
+{
+	return dce_aux_transfer_with_retries(ddc, payload);
+}
+
+
+bool try_to_configure_aux_timeout(struct ddc_service *ddc,
+		uint32_t timeout)
+{
+	bool result = false;
+	struct ddc *ddc_pin = ddc->ddc_pin;
+
+	if (((ddc->link->chip_caps & AMD_EXT_DISPLAY_PATH_CAPS__EXT_CHIP_MASK) == AMD_EXT_DISPLAY_PATH_CAPS__DP_FIXED_VS_EN) &&
+			!ddc->link->dc->debug.disable_fixed_vs_aux_timeout_wa &&
+			ddc->ctx->dce_version == DCN_VERSION_3_1) {
+		/* Fixed VS workaround for AUX timeout */
+		const uint32_t fixed_vs_address = 0xF004F;
+		const uint8_t fixed_vs_data[4] = {0x1, 0x22, 0x63, 0xc};
+
+		core_link_write_dpcd(ddc->link,
+				fixed_vs_address,
+				fixed_vs_data,
+				sizeof(fixed_vs_data));
+
+		timeout = 3072;
+	}
+
+	/* Do not try to access nonexistent DDC pin. */
+	if (ddc->link->ep_type != DISPLAY_ENDPOINT_PHY)
+		return true;
+
+	if (ddc->ctx->dc->config.dp_connector_no_native_i2c && ddc->link->no_ddc_pin) {
+		if (ddc->ctx->dc->res_pool->engines[ddc->link->aux_hw_inst]->funcs->configure_timeout) {
+			ddc->ctx->dc->res_pool->engines[ddc->link->aux_hw_inst]->funcs->configure_timeout(ddc, timeout);
+			result = true;
+		}
+	} else {
+		if (ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en]->funcs->configure_timeout) {
+			ddc->ctx->dc->res_pool->engines[ddc_pin->pin_data->en]->funcs->configure_timeout(ddc, timeout);
+			result = true;
+		}
+
+	}
+	return result;
+}
+
+struct ddc *get_ddc_pin(struct ddc_service *ddc_service)
+{
+	return ddc_service->ddc_pin;
+}
+
+void write_scdc_data(struct ddc_service *ddc_service,
+		uint32_t pix_clk,
+		bool lte_340_scramble)
+{
+	bool over_340_mhz = pix_clk > 340000 ? 1 : 0;
+	uint8_t slave_address = HDMI_SCDC_ADDRESS;
+	uint8_t offset = HDMI_SCDC_SINK_VERSION;
+	uint8_t sink_version = 0;
+	uint8_t write_buffer[2] = {0};
+	/*Lower than 340 Scramble bit from SCDC caps*/
+
+	if (ddc_service->link->local_sink &&
+		(ddc_service->link->local_sink->edid_caps.panel_patch.skip_scdc_overwrite ||
+		!ddc_service->link->local_sink->edid_caps.scdc_present))
+		return;
+	hdmi_frl_LTS_clear_Link_Setting(ddc_service);
+	hdmi_frl_LTS_clear_Update_flag(ddc_service);
+
+	link_query_ddc_data(ddc_service, slave_address, &offset,
+			sizeof(offset), &sink_version, sizeof(sink_version));
+	if (sink_version == 1) {
+		/*Source Version = 1*/
+		write_buffer[0] = HDMI_SCDC_SOURCE_VERSION;
+		write_buffer[1] = 1;
+		link_query_ddc_data(ddc_service, slave_address,
+				write_buffer, sizeof(write_buffer), NULL, 0);
+		/*Read Request from SCDC caps*/
+	}
+	write_buffer[0] = HDMI_SCDC_TMDS_CONFIG;
+
+	if (over_340_mhz) {
+		write_buffer[1] = 3;
+	} else if (lte_340_scramble) {
+		write_buffer[1] = 1;
+	} else {
+		write_buffer[1] = 0;
+	}
+	link_query_ddc_data(ddc_service, slave_address, write_buffer,
+			sizeof(write_buffer), NULL, 0);
+}
+
+void read_scdc_data(struct ddc_service *ddc_service)
+{
+	uint8_t slave_address = HDMI_SCDC_ADDRESS;
+	uint8_t offset = HDMI_SCDC_TMDS_CONFIG;
+	uint8_t tmds_config = 0;
+
+	if (ddc_service->link->local_sink &&
+		ddc_service->link->local_sink->edid_caps.panel_patch.skip_scdc_overwrite)
+		return;
+
+	link_query_ddc_data(ddc_service, slave_address, &offset,
+			sizeof(offset), &tmds_config, sizeof(tmds_config));
+	if (tmds_config & 0x1) {
+		union hdmi_scdc_status_flags_data status_data = {0};
+		uint8_t scramble_status = 0;
+
+		offset = HDMI_SCDC_SCRAMBLER_STATUS;
+		link_query_ddc_data(ddc_service, slave_address,
+				&offset, sizeof(offset), &scramble_status,
+				sizeof(scramble_status));
+		offset = HDMI_SCDC_STATUS_FLAGS;
+		link_query_ddc_data(ddc_service, slave_address,
+				&offset, sizeof(offset), &status_data.byte,
+				sizeof(status_data.byte));
+	}
+}
+void write_idcc_data(struct ddc_service *ddc_service, enum hdmi_idcc_scope idcc_scope,
+		uint8_t *write_buf, uint8_t offset, uint8_t write_len)
+{
+	uint8_t slave_address = HDMI_IDCC_ADDRESS;
+	uint8_t idcc_header[5] = {0};
+	uint8_t dummy_buf[1] = {0};
+	uint8_t checksum = 0;
+	int i;
+
+	idcc_header[0] = HDMI_IDCC_MARKER0;
+	idcc_header[1] = HDMI_IDCC_MARKER1;
+	idcc_header[2] = (uint8_t)(HDMI_IDCC_MARKER2 | idcc_scope);
+	idcc_header[3] = offset;
+	idcc_header[4] = write_len;
+
+	/* Write the IDCC header */
+	for (i = 0; i < sizeof(idcc_header); ++i) {
+		link_query_ddc_data(ddc_service, slave_address,
+				&idcc_header[i], 1,
+				&dummy_buf[0], 1);
+		checksum += idcc_header[i];
+	}
+
+	/* Write the payload */
+	for (i = 0; i < write_len; ++i) {
+		link_query_ddc_data(ddc_service, slave_address,
+				&write_buf[i], 1,
+				&dummy_buf[0], 1);
+		checksum += write_buf[i];
+	}
+
+	/* Write the checksum */
+	if (write_len > 0) {
+		checksum = 0xff - checksum + 1;
+		link_query_ddc_data(ddc_service, slave_address,
+			&checksum, 1,
+			&dummy_buf[0], 1);
+	}
+}
+
+int read_idcc_data(struct ddc_service *ddc_service, enum hdmi_idcc_scope idcc_scope,
+		uint8_t *read_buf, uint8_t offset, uint8_t read_len)
+{
+	uint8_t slave_address = HDMI_IDCC_ADDRESS;
+	uint8_t idcc_header[5] = {0};
+	uint8_t dummy_buf[1] = {0};
+	uint8_t read_buf_local[6] = {0};
+	uint8_t checksum = 0;
+	int i;
+
+	idcc_header[0] = HDMI_IDCC_MARKER0;
+	idcc_header[1] = HDMI_IDCC_MARKER1;
+	idcc_header[2] = (uint8_t)(HDMI_IDCC_MARKER2 | idcc_scope);
+	idcc_header[3] = offset;
+	idcc_header[4] = read_len;
+
+	/* Write the IDCC header */
+	for (i = 0; i < sizeof(idcc_header); ++i) {
+		link_query_ddc_data(ddc_service, slave_address,
+				&idcc_header[i], 1,
+				&dummy_buf[0], 1);
+		checksum += idcc_header[i];
+	}
+
+	/* Read the payload */
+	if (read_len > 0) {
+		dummy_buf[0] = 0x01;
+		if (read_len > 5)
+			read_len = 5;
+		link_query_ddc_data(ddc_service, slave_address,
+				&dummy_buf[0], 1,
+				&read_buf_local[0], read_len + 1);
+
+		memcpy(read_buf, read_buf_local, read_len);
+
+		/* Check checksum */
+		checksum = read_buf_local[read_len];
+		for (i = 0; i < 5; ++i)
+			checksum += idcc_header[i];
+		for (i = 0; i < read_len; ++i)
+			checksum += read_buf_local[i];
+		if (checksum != 0)
+			return -1;
+	}
+
+	return read_len;
+}

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_ddc.h

@@ -0,0 +1,110 @@
+/*
+ * Copyright 2012-15 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#ifndef __DAL_DDC_SERVICE_H__
+#define __DAL_DDC_SERVICE_H__
+
+#include "link_service.h"
+
+#define AUX_POWER_UP_WA_DELAY 500
+#define I2C_OVER_AUX_DEFER_WA_DELAY 70
+#define DPVGA_DONGLE_AUX_DEFER_WA_DELAY 40
+#define I2C_OVER_AUX_DEFER_WA_DELAY_1MS 1
+#define LINK_AUX_DEFAULT_LTTPR_TIMEOUT_PERIOD 3200 /*us*/
+#define LINK_AUX_DEFAULT_TIMEOUT_PERIOD 552 /*us*/
+
+#define EDID_SEGMENT_SIZE 256
+
+struct ddc_service *link_create_ddc_service(
+		struct ddc_service_init_data *ddc_init_data);
+
+void link_destroy_ddc_service(struct ddc_service **ddc);
+
+void set_ddc_transaction_type(
+		struct ddc_service *ddc,
+		enum ddc_transaction_type type);
+
+uint32_t link_get_aux_defer_delay(struct ddc_service *ddc);
+
+bool link_is_in_aux_transaction_mode(struct ddc_service *ddc);
+
+bool try_to_configure_aux_timeout(struct ddc_service *ddc,
+		uint32_t timeout);
+
+bool link_query_ddc_data(
+		struct ddc_service *ddc,
+		uint32_t address,
+		uint8_t *write_buf,
+		uint32_t write_size,
+		uint8_t *read_buf,
+		uint32_t read_size);
+
+/* Attempt to submit an aux payload, retrying on timeouts, defers, and busy
+ * states as outlined in the DP spec.  Returns true if the request was
+ * successful.
+ *
+ * NOTE: The function requires explicit mutex on DM side in order to prevent
+ * potential race condition. DC components should call the dpcd read/write
+ * function in dm_helpers in order to access dpcd safely
+ */
+bool link_aux_transfer_with_retries_no_mutex(struct ddc_service *ddc,
+		struct aux_payload *payload);
+
+bool link_configure_fixed_vs_pe_retimer(
+		struct ddc_service *ddc,
+		const uint8_t *data,
+		uint32_t length);
+
+bool link_query_fixed_vs_pe_retimer(
+		struct ddc_service *ddc,
+		uint8_t *data,
+		uint32_t length);
+
+uint32_t link_get_fixed_vs_pe_retimer_read_address(struct dc_link *link);
+uint32_t link_get_fixed_vs_pe_retimer_write_address(struct dc_link *link);
+
+
+void write_scdc_data(
+		struct ddc_service *ddc_service,
+		uint32_t pix_clk,
+		bool lte_340_scramble);
+
+void read_scdc_data(
+		struct ddc_service *ddc_service);
+
+void write_idcc_data(struct ddc_service *ddc_service, enum hdmi_idcc_scope idcc_scope,
+		uint8_t *write_buf, uint8_t offset, uint8_t write_len);
+int read_idcc_data(struct ddc_service *ddc_service, enum hdmi_idcc_scope idcc_scope,
+		uint8_t *read_buf, uint8_t offset, uint8_t read_len);
+void set_dongle_type(struct ddc_service *ddc,
+		enum display_dongle_type dongle_type);
+
+struct ddc *get_ddc_pin(struct ddc_service *ddc_service);
+
+int link_aux_transfer_raw(struct ddc_service *ddc,
+		struct aux_payload *payload,
+		enum aux_return_code_type *operation_result);
+#endif /* __DAL_DDC_SERVICE_H__ */
+

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_capability.h

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#ifndef __DC_LINK_DP_CAPABILITY_H__
+#define __DC_LINK_DP_CAPABILITY_H__
+
+#include "link_service.h"
+
+bool detect_dp_sink_caps(struct dc_link *link);
+
+void detect_edp_sink_caps(struct dc_link *link);
+
+struct dc_link_settings dp_get_max_link_cap(struct dc_link *link);
+
+bool dp_get_max_link_enc_cap(const struct dc_link *link,
+		struct dc_link_settings *max_link_enc_cap);
+
+const struct dc_link_settings *dp_get_verified_link_cap(
+		const struct dc_link *link);
+
+enum dp_link_encoding link_dp_get_encoding_format(
+		const struct dc_link_settings *link_settings);
+
+enum dc_status dp_retrieve_lttpr_cap(struct dc_link *link);
+
+/* Convert PHY repeater count read from DPCD uint8_t. */
+uint8_t dp_parse_lttpr_repeater_count(uint8_t lttpr_repeater_count);
+
+/* Calculate embedded LTTPR address offset for vendor-specific behaviour */
+uint32_t dp_get_closest_lttpr_offset(uint8_t lttpr_count);
+
+bool dp_is_sink_present(struct dc_link *link);
+
+bool dp_is_lttpr_present(struct dc_link *link);
+
+bool dp_is_fec_supported(const struct dc_link *link);
+
+bool is_dp_active_dongle(const struct dc_link *link);
+
+bool is_dp_branch_device(const struct dc_link *link);
+
+void dpcd_write_cable_id_to_dprx(struct dc_link *link);
+
+bool dp_should_enable_fec(const struct dc_link *link);
+
+bool dp_is_128b_132b_signal(struct pipe_ctx *pipe_ctx);
+
+/* Initialize output parameter lt_settings. */
+void dp_decide_training_settings(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	const struct dc_link_settings *link_setting,
+	struct link_training_settings *lt_settings);
+
+bool link_decide_link_settings(
+	struct dc_stream_state *stream,
+	struct dc_link_settings *link_setting);
+
+bool edp_decide_link_settings(struct dc_link *link,
+		struct dc_link_settings *link_setting, uint32_t req_bw);
+
+bool decide_edp_link_settings_with_dsc(struct dc_link *link,
+		struct dc_link_settings *link_setting,
+		uint32_t req_bw,
+		enum dc_link_rate max_link_rate);
+
+enum dp_link_encoding mst_decide_link_encoding_format(const struct dc_link *link);
+
+void dpcd_set_source_specific_data(struct dc_link *link);
+
+/*query dpcd for version and mst cap addresses*/
+bool read_is_mst_supported(struct dc_link *link);
+
+bool decide_fallback_link_setting(
+		struct dc_link *link,
+		struct dc_link_settings *max,
+		struct dc_link_settings *cur,
+		enum link_training_result training_result);
+
+bool dp_verify_link_cap_with_retries(
+	struct dc_link *link,
+	struct dc_link_settings *known_limit_link_setting,
+	int attempts);
+
+uint32_t link_bw_kbps_from_raw_frl_link_rate_data(uint8_t bw);
+
+bool dp_overwrite_extended_receiver_cap(struct dc_link *link);
+
+uint8_t dp_get_lttpr_count(struct dc_link *link);
+
+void edp_get_alpm_support(struct dc_link *link,
+	bool *auxless_support,
+	bool *auxwake_support);
+
+#endif /* __DC_LINK_DP_CAPABILITY_H__ */

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia.c

@@ -0,0 +1,171 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright 2021 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#include "dc.h"
+#include "inc/core_status.h"
+#include "dpcd_defs.h"
+
+#include "link_dp_dpia.h"
+#include "link_hwss.h"
+#include "dm_helpers.h"
+#include "dmub/inc/dmub_cmd.h"
+#include "link_dpcd.h"
+#include "link_dp_training.h"
+#include "dc_dmub_srv.h"
+
+#define DC_LOGGER \
+	link->ctx->logger
+
+/** @note Can remove once DP tunneling registers in upstream include/drm/drm_dp_helper.h */
+/* DPCD DP Tunneling over USB4 */
+#define DP_TUNNELING_CAPABILITIES_SUPPORT 0xe000d
+#define DP_IN_ADAPTER_INFO                0xe000e
+#define DP_USB4_DRIVER_ID                 0xe000f
+#define DP_USB4_ROUTER_TOPOLOGY_ID        0xe001b
+
+enum dc_status dpcd_get_tunneling_device_data(struct dc_link *link)
+{
+	enum dc_status status = DC_OK;
+	uint8_t dpcd_dp_tun_data[3] = {0};
+	uint8_t dpcd_topology_data[DPCD_USB4_TOPOLOGY_ID_LEN] = {0};
+	uint8_t i = 0;
+
+	status = core_link_read_dpcd(
+			link,
+			DP_TUNNELING_CAPABILITIES_SUPPORT,
+			dpcd_dp_tun_data,
+			sizeof(dpcd_dp_tun_data));
+
+	if (status != DC_OK)
+		goto err;
+
+	link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.raw =
+			dpcd_dp_tun_data[DP_TUNNELING_CAPABILITIES_SUPPORT - DP_TUNNELING_CAPABILITIES_SUPPORT];
+
+	if (link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dp_tunneling == false)
+		goto err;
+
+	link->dpcd_caps.usb4_dp_tun_info.dpia_info.raw =
+			dpcd_dp_tun_data[DP_IN_ADAPTER_INFO - DP_TUNNELING_CAPABILITIES_SUPPORT];
+	link->dpcd_caps.usb4_dp_tun_info.usb4_driver_id =
+			dpcd_dp_tun_data[DP_USB4_DRIVER_ID - DP_TUNNELING_CAPABILITIES_SUPPORT] & 0x0F;
+
+	if (link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dpia_bw_alloc) {
+		status = core_link_read_dpcd(link, USB4_DRIVER_BW_CAPABILITY,
+				dpcd_dp_tun_data, 2);
+
+		if (status != DC_OK)
+			goto err;
+
+		link->dpcd_caps.usb4_dp_tun_info.driver_bw_cap.raw =
+			dpcd_dp_tun_data[USB4_DRIVER_BW_CAPABILITY - USB4_DRIVER_BW_CAPABILITY];
+		link->dpcd_caps.usb4_dp_tun_info.dpia_tunnel_info.raw =
+			dpcd_dp_tun_data[DP_IN_ADAPTER_TUNNEL_INFO - USB4_DRIVER_BW_CAPABILITY];
+	}
+
+	DC_LOG_DEBUG("%s: Link[%d]  DP tunneling support  (RouterId=%d  AdapterId=%d)  "
+			"DPIA_BW_Alloc_support=%d "
+			"CM_BW_Alloc_support=%d ",
+			__func__, link->link_index,
+			link->dpcd_caps.usb4_dp_tun_info.usb4_driver_id,
+			link->dpcd_caps.usb4_dp_tun_info.dpia_info.bits.dpia_num,
+			link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dpia_bw_alloc,
+			link->dpcd_caps.usb4_dp_tun_info.driver_bw_cap.bits.driver_bw_alloc_support);
+
+	status = core_link_read_dpcd(
+			link,
+			DP_USB4_ROUTER_TOPOLOGY_ID,
+			dpcd_topology_data,
+			sizeof(dpcd_topology_data));
+
+	if (status != DC_OK)
+		goto err;
+
+	for (i = 0; i < DPCD_USB4_TOPOLOGY_ID_LEN; i++)
+		link->dpcd_caps.usb4_dp_tun_info.usb4_topology_id[i] = dpcd_topology_data[i];
+
+err:
+	return status;
+}
+
+bool dpia_query_hpd_status(struct dc_link *link)
+{
+	union dmub_rb_cmd cmd = {0};
+	struct dc_dmub_srv *dmub_srv = link->ctx->dmub_srv;
+
+	/* prepare QUERY_HPD command */
+	cmd.query_hpd.header.type = DMUB_CMD__QUERY_HPD_STATE;
+	cmd.query_hpd.header.payload_bytes = sizeof(cmd.query_hpd.data);
+	cmd.query_hpd.data.instance = (uint8_t)(link->link_id.enum_id - ENUM_ID_1);
+	cmd.query_hpd.data.ch_type = AUX_CHANNEL_DPIA;
+
+	/* Query dpia hpd status from dmub */
+	if (dc_wake_and_execute_dmub_cmd(dmub_srv->ctx, &cmd,
+		DM_DMUB_WAIT_TYPE_WAIT_WITH_REPLY) &&
+	    cmd.query_hpd.data.status == AUX_RET_SUCCESS) {
+		DC_LOG_DEBUG("%s: for link(%d) dpia(%d) success, current_hpd_status(%d) new_hpd_status(%d)\n",
+			__func__,
+			link->link_index,
+			link->link_id.enum_id - ENUM_ID_1,
+			link->hpd_status,
+			cmd.query_hpd.data.result);
+		link->hpd_status = cmd.query_hpd.data.result;
+	} else {
+		DC_LOG_ERROR("%s: for link(%d) dpia(%d) failed with status(%d), current_hpd_status(%d) new_hpd_status(0)\n",
+			__func__,
+			link->link_index,
+			link->link_id.enum_id - ENUM_ID_1,
+			cmd.query_hpd.data.status,
+			link->hpd_status);
+		link->hpd_status = false;
+	}
+
+	return link->hpd_status;
+}
+
+void link_decide_dp_tunnel_settings(struct dc_stream_state *stream,
+			struct dc_tunnel_settings *dp_tunnel_setting)
+{
+	struct dc_link *link = stream->link;
+
+	memset(dp_tunnel_setting, 0, sizeof(*dp_tunnel_setting));
+
+	if ((stream->signal == SIGNAL_TYPE_DISPLAY_PORT) || (stream->signal == SIGNAL_TYPE_DISPLAY_PORT_MST)) {
+		dp_tunnel_setting->should_enable_dp_tunneling =
+					link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dp_tunneling;
+
+		if (link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dpia_bw_alloc
+				&& link->dpcd_caps.usb4_dp_tun_info.driver_bw_cap.bits.driver_bw_alloc_support) {
+			dp_tunnel_setting->should_use_dp_bw_allocation = true;
+			dp_tunnel_setting->cm_id = link->dpcd_caps.usb4_dp_tun_info.usb4_driver_id & 0x0F;
+			dp_tunnel_setting->group_id = link->dpcd_caps.usb4_dp_tun_info.dpia_tunnel_info.bits.group_id;
+			dp_tunnel_setting->estimated_bw = link->dpia_bw_alloc_config.estimated_bw;
+			dp_tunnel_setting->allocated_bw = link->dpia_bw_alloc_config.allocated_bw;
+			dp_tunnel_setting->bw_granularity = link->dpia_bw_alloc_config.bw_granularity;
+		}
+	}
+}
+

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia.h

@@ -0,0 +1,47 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright 2021 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#ifndef __DC_LINK_DPIA_H__
+#define __DC_LINK_DPIA_H__
+
+#include "link_service.h"
+
+/* Read tunneling device capability from DPCD and update link capability
+ * accordingly.
+ */
+enum dc_status dpcd_get_tunneling_device_data(struct dc_link *link);
+
+/* Query hot plug status of USB4 DP tunnel.
+ * Returns true if HPD high.
+ */
+bool dpia_query_hpd_status(struct dc_link *link);
+
+/* Decide the DP tunneling settings based on the DPCD capabilities
+ */
+void link_decide_dp_tunnel_settings(struct dc_stream_state *stream,
+			struct dc_tunnel_settings *dp_tunnel_setting);
+
+#endif /* __DC_LINK_DPIA_H__ */

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia_bw.c

@@ -0,0 +1,448 @@
+
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+/*********************************************************************/
+// USB4 DPIA BANDWIDTH ALLOCATION LOGIC
+/*********************************************************************/
+#include "link_dp_dpia_bw.h"
+#include "link_dpcd.h"
+#include "dc_dmub_srv.h"
+
+#define DC_LOGGER \
+	link->ctx->logger
+
+#define Kbps_TO_Gbps (1000 * 1000)
+
+#define MST_TIME_SLOT_COUNT 64
+
+// ------------------------------------------------------------------
+// PRIVATE FUNCTIONS
+// ------------------------------------------------------------------
+/*
+ * Always Check the following:
+ *  - Is it USB4 link?
+ *  - Is HPD HIGH?
+ *  - Is BW Allocation Support Mode enabled on DP-Tx?
+ */
+static bool link_dp_is_bw_alloc_available(struct dc_link *link)
+{
+	return (link && link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dp_tunneling
+		&& link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dpia_bw_alloc
+		&& link->dpcd_caps.usb4_dp_tun_info.driver_bw_cap.bits.driver_bw_alloc_support);
+}
+
+static void reset_bw_alloc_struct(struct dc_link *link)
+{
+	link->dpia_bw_alloc_config.bw_alloc_enabled = false;
+	link->dpia_bw_alloc_config.link_verified_bw = 0;
+	link->dpia_bw_alloc_config.link_max_bw = 0;
+	link->dpia_bw_alloc_config.allocated_bw = 0;
+	link->dpia_bw_alloc_config.estimated_bw = 0;
+	link->dpia_bw_alloc_config.bw_granularity = 0;
+	link->dpia_bw_alloc_config.dp_overhead = 0;
+	link->dpia_bw_alloc_config.nrd_max_lane_count = 0;
+	link->dpia_bw_alloc_config.nrd_max_link_rate = 0;
+	for (int i = 0; i < MAX_SINKS_PER_LINK; i++)
+		link->dpia_bw_alloc_config.remote_sink_req_bw[i] = 0;
+	DC_LOG_DEBUG("reset usb4 bw alloc of link(%d)\n", link->link_index);
+}
+
+#define BW_GRANULARITY_0 4 // 0.25 Gbps
+#define BW_GRANULARITY_1 2 // 0.5 Gbps
+#define BW_GRANULARITY_2 1 // 1 Gbps
+
+static uint8_t get_bw_granularity(struct dc_link *link)
+{
+	uint8_t bw_granularity = 0;
+
+	core_link_read_dpcd(
+			link,
+			DP_BW_GRANULALITY,
+			&bw_granularity,
+			sizeof(uint8_t));
+
+	switch (bw_granularity & 0x3) {
+	case 0:
+		bw_granularity = BW_GRANULARITY_0;
+		break;
+	case 1:
+		bw_granularity = BW_GRANULARITY_1;
+		break;
+	case 2:
+	default:
+		bw_granularity = BW_GRANULARITY_2;
+		break;
+	}
+
+	return bw_granularity;
+}
+
+static int get_estimated_bw(struct dc_link *link)
+{
+	uint8_t bw_estimated_bw = 0;
+
+	core_link_read_dpcd(
+			link,
+			ESTIMATED_BW,
+			&bw_estimated_bw,
+			sizeof(uint8_t));
+
+	return bw_estimated_bw * (Kbps_TO_Gbps / link->dpia_bw_alloc_config.bw_granularity);
+}
+
+static uint8_t get_non_reduced_max_link_rate(struct dc_link *link)
+{
+	uint8_t nrd_max_link_rate = 0;
+
+	core_link_read_dpcd(
+			link,
+			DP_TUNNELING_MAX_LINK_RATE,
+			&nrd_max_link_rate,
+			sizeof(uint8_t));
+
+	return nrd_max_link_rate;
+}
+
+static uint8_t get_non_reduced_max_lane_count(struct dc_link *link)
+{
+	uint8_t nrd_max_lane_count = 0;
+
+	core_link_read_dpcd(
+			link,
+			DP_TUNNELING_MAX_LANE_COUNT,
+			&nrd_max_lane_count,
+			sizeof(uint8_t));
+
+	return nrd_max_lane_count;
+}
+
+/*
+ * Read all New BW alloc configuration ex: estimated_bw, allocated_bw,
+ * granuality, Driver_ID, CM_Group, & populate the BW allocation structs
+ * for host router and dpia
+ */
+static void retrieve_usb4_dp_bw_allocation_info(struct dc_link *link)
+{
+	reset_bw_alloc_struct(link);
+
+	/* init the known values */
+	link->dpia_bw_alloc_config.bw_granularity = get_bw_granularity(link);
+	link->dpia_bw_alloc_config.estimated_bw = get_estimated_bw(link);
+	link->dpia_bw_alloc_config.nrd_max_link_rate = get_non_reduced_max_link_rate(link);
+	link->dpia_bw_alloc_config.nrd_max_lane_count = get_non_reduced_max_lane_count(link);
+
+	DC_LOG_DEBUG("%s: bw_granularity(%d), estimated_bw(%d)\n",
+		__func__, link->dpia_bw_alloc_config.bw_granularity,
+		link->dpia_bw_alloc_config.estimated_bw);
+	DC_LOG_DEBUG("%s: nrd_max_link_rate(%d), nrd_max_lane_count(%d)\n",
+		__func__, link->dpia_bw_alloc_config.nrd_max_link_rate,
+		link->dpia_bw_alloc_config.nrd_max_lane_count);
+}
+
+/*
+ * Cleanup function for when the dpia is unplugged to reset struct
+ * and perform any required clean up
+ *
+ * @link: pointer to the dc_link struct instance
+ *
+ * return: none
+ */
+static void dpia_bw_alloc_unplug(struct dc_link *link)
+{
+	if (link) {
+		DC_LOG_DEBUG("%s: resetting BW alloc config for link(%d)\n",
+			__func__, link->link_index);
+		reset_bw_alloc_struct(link);
+	}
+}
+
+static void link_dpia_send_bw_alloc_request(struct dc_link *link, int req_bw)
+{
+	uint32_t request_reg_val;
+	uint32_t temp, request_bw;
+
+	if (link->dpia_bw_alloc_config.bw_granularity == 0) {
+		DC_LOG_ERROR("%s:  Link[%d]:  bw_granularity is zero!", __func__, link->link_index);
+		return;
+	}
+
+	temp = req_bw * link->dpia_bw_alloc_config.bw_granularity;
+	request_reg_val = temp / Kbps_TO_Gbps;
+
+	/* Always make sure to add more to account for floating points */
+	if (temp % Kbps_TO_Gbps)
+		++request_reg_val;
+
+	request_bw = request_reg_val * (Kbps_TO_Gbps / link->dpia_bw_alloc_config.bw_granularity);
+
+	if (request_bw > (uint32_t)link->dpia_bw_alloc_config.estimated_bw) {
+		DC_LOG_ERROR("%s:  Link[%d]:  Request BW (%d --> %d) > Estimated BW (%d)... Set to Estimated BW!",
+				__func__, link->link_index,
+				req_bw, request_bw, link->dpia_bw_alloc_config.estimated_bw);
+		req_bw = link->dpia_bw_alloc_config.estimated_bw;
+
+		temp = req_bw * link->dpia_bw_alloc_config.bw_granularity;
+		request_reg_val = temp / Kbps_TO_Gbps;
+		if (temp % Kbps_TO_Gbps)
+			++request_reg_val;
+	}
+
+	link->dpia_bw_alloc_config.allocated_bw = request_bw;
+	DC_LOG_DC("%s:  Link[%d]:  Request BW:  %d", __func__, link->link_index, request_bw);
+
+	uint8_t requested_bw_dpcd = (uint8_t)request_reg_val;
+	core_link_write_dpcd(link, REQUESTED_BW, &requested_bw_dpcd,
+		sizeof(uint8_t));
+}
+
+// ------------------------------------------------------------------
+// PUBLIC FUNCTIONS
+// ------------------------------------------------------------------
+bool link_dpia_enable_usb4_dp_bw_alloc_mode(struct dc_link *link)
+{
+	bool ret = false;
+	uint8_t val;
+
+	val = DPTX_BW_ALLOC_MODE_ENABLE | DPTX_BW_ALLOC_UNMASK_IRQ;
+
+	if (core_link_write_dpcd(link, DPTX_BW_ALLOCATION_MODE_CONTROL, &val, sizeof(uint8_t)) == DC_OK) {
+		DC_LOG_DEBUG("%s:  link[%d] DPTX BW allocation mode enabled", __func__, link->link_index);
+
+		retrieve_usb4_dp_bw_allocation_info(link);
+
+		if (
+				link->dpia_bw_alloc_config.nrd_max_link_rate
+				&& link->dpia_bw_alloc_config.nrd_max_lane_count) {
+			link->reported_link_cap.link_rate = link->dpia_bw_alloc_config.nrd_max_link_rate;
+			link->reported_link_cap.lane_count = link->dpia_bw_alloc_config.nrd_max_lane_count;
+		}
+
+		link->dpia_bw_alloc_config.bw_alloc_enabled = true;
+		ret = true;
+
+		if (link->dc->debug.dpia_debug.bits.enable_usb4_bw_zero_alloc_patch) {
+			/*
+			 * During DP tunnel creation, the CM preallocates BW
+			 * and reduces the estimated BW of other DPIAs.
+			 * The CM releases the preallocation only when the allocation is complete.
+			 * Perform a zero allocation to make the CM release the preallocation
+			 * and correctly update the estimated BW for all DPIAs per host router.
+			 */
+			link_dp_dpia_allocate_usb4_bandwidth_for_stream(link, 0);
+		}
+	} else
+		DC_LOG_DEBUG("%s:  link[%d] failed to enable DPTX BW allocation mode", __func__, link->link_index);
+
+	return ret;
+}
+
+/*
+ * Handle DP BW allocation status register
+ *
+ * @link: pointer to the dc_link struct instance
+ * @status: content of DP tunneling status DPCD register
+ *
+ * return: none
+ */
+void link_dp_dpia_handle_bw_alloc_status(struct dc_link *link, uint8_t status)
+{
+	if (status & DP_TUNNELING_BW_REQUEST_SUCCEEDED) {
+		DC_LOG_DEBUG("%s: BW Allocation request succeeded on link(%d)",
+				__func__, link->link_index);
+	}
+
+	if (status & DP_TUNNELING_BW_REQUEST_FAILED) {
+		DC_LOG_DEBUG("%s: BW Allocation request failed on link(%d)  allocated/estimated BW=%d",
+				__func__, link->link_index, link->dpia_bw_alloc_config.estimated_bw);
+
+		link_dpia_send_bw_alloc_request(link, link->dpia_bw_alloc_config.estimated_bw);
+	}
+
+	if (status & DP_TUNNELING_BW_ALLOC_CAP_CHANGED) {
+		link->dpia_bw_alloc_config.bw_granularity = get_bw_granularity(link);
+
+		DC_LOG_DEBUG("%s: Granularity changed on link(%d)  new granularity=%d",
+				__func__, link->link_index, link->dpia_bw_alloc_config.bw_granularity);
+	}
+
+	if (status & DP_TUNNELING_ESTIMATED_BW_CHANGED) {
+		link->dpia_bw_alloc_config.estimated_bw = get_estimated_bw(link);
+
+		DC_LOG_DEBUG("%s: Estimated BW changed on link(%d)  new estimated BW=%d",
+				__func__, link->link_index, link->dpia_bw_alloc_config.estimated_bw);
+	}
+
+	core_link_write_dpcd(
+		link, DP_TUNNELING_STATUS,
+		&status, sizeof(status));
+}
+
+/*
+ * Handle the DP Bandwidth allocation for DPIA
+ *
+ */
+void dpia_handle_usb4_bandwidth_allocation_for_link(struct dc_link *link, int peak_bw)
+{
+	if (link && link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dp_tunneling
+			&& link->dpia_bw_alloc_config.bw_alloc_enabled) {
+		if (peak_bw > 0) {
+			// If DP over USB4 then we need to check BW allocation
+			link->dpia_bw_alloc_config.link_max_bw = peak_bw;
+
+			link_dpia_send_bw_alloc_request(link, peak_bw);
+		} else
+			dpia_bw_alloc_unplug(link);
+	}
+}
+
+void link_dp_dpia_allocate_usb4_bandwidth_for_stream(struct dc_link *link, int req_bw)
+{
+	link->dpia_bw_alloc_config.estimated_bw = get_estimated_bw(link);
+
+	DC_LOG_DEBUG("%s: ENTER: link[%d] hpd(%d)  Allocated_BW: %d  Estimated_BW: %d  Req_BW: %d",
+		__func__, link->link_index, link->hpd_status,
+		link->dpia_bw_alloc_config.allocated_bw,
+		link->dpia_bw_alloc_config.estimated_bw,
+		req_bw);
+
+	if (link_dp_is_bw_alloc_available(link))
+		link_dpia_send_bw_alloc_request(link, req_bw);
+	else
+		DC_LOG_DEBUG("%s:  BW Allocation mode not available", __func__);
+}
+
+uint32_t link_dpia_get_dp_overhead(const struct dc_link *link)
+{
+	uint32_t link_dp_overhead = 0;
+
+	if ((link->type == dc_connection_mst_branch) &&
+				!link->dpcd_caps.channel_coding_cap.bits.DP_128b_132b_SUPPORTED) {
+		/* For 8b/10b encoding: MTP is 64 time slots long, slot 0 is used for MTPH
+		 * MST overhead is 1/64 of link bandwidth (excluding any overhead)
+		 */
+		const struct dc_link_settings *link_cap = dc_link_get_link_cap(link);
+
+		if (link_cap) {
+			uint32_t link_bw_in_kbps = (uint32_t)link_cap->link_rate *
+					   (uint32_t)link_cap->lane_count *
+					   LINK_RATE_REF_FREQ_IN_KHZ * 8;
+			link_dp_overhead = (link_bw_in_kbps / MST_TIME_SLOT_COUNT)
+						+ ((link_bw_in_kbps % MST_TIME_SLOT_COUNT) ? 1 : 0);
+		}
+	}
+
+	return link_dp_overhead;
+}
+
+/*
+ * Aggregates the DPIA bandwidth usage for the respective USB4 Router.
+ * And then validate if the required bandwidth is within the router's capacity.
+ *
+ * @dc_validation_dpia_set: pointer to the dc_validation_dpia_set
+ * @count: number of DPIA validation sets
+ *
+ * return: true if validation is succeeded
+ */
+bool link_dpia_validate_dp_tunnel_bandwidth(const struct dc_validation_dpia_set *dpia_link_sets, uint8_t count)
+{
+	uint32_t granularity_Gbps;
+	const struct dc_link *link;
+	uint32_t link_bw_granularity;
+	uint32_t link_required_bw;
+	struct usb4_router_validation_set router_sets[MAX_HOST_ROUTERS_NUM] = { 0 };
+	uint8_t i;
+	bool is_success = true;
+	uint8_t router_count = 0;
+
+	if ((dpia_link_sets == NULL) || (count == 0))
+		return is_success;
+
+	// Iterate through each DP tunneling link (DPIA).
+	// Aggregate its bandwidth requirements onto the respective USB4 router.
+	for (i = 0; i < count; i++) {
+		link = dpia_link_sets[i].link;
+		link_required_bw = dpia_link_sets[i].required_bw;
+		const struct dc_tunnel_settings *dp_tunnel_settings = dpia_link_sets[i].tunnel_settings;
+
+		if ((link == NULL) || (dp_tunnel_settings == NULL) || dp_tunnel_settings->bw_granularity == 0)
+			break;
+
+		if (link->type == dc_connection_mst_branch)
+			link_required_bw += link_dpia_get_dp_overhead(link);
+
+		granularity_Gbps = (Kbps_TO_Gbps / dp_tunnel_settings->bw_granularity);
+		link_bw_granularity = (link_required_bw / granularity_Gbps) * granularity_Gbps +
+				((link_required_bw % granularity_Gbps) ? granularity_Gbps : 0);
+
+		// Find or add the USB4 router associated with the current DPIA link
+		for (uint8_t j = 0; j < MAX_HOST_ROUTERS_NUM; j++) {
+			if (router_sets[j].is_valid == false) {
+				router_sets[j].is_valid = true;
+				router_sets[j].cm_id = dp_tunnel_settings->cm_id;
+				router_count++;
+			}
+
+			if (router_sets[j].cm_id == dp_tunnel_settings->cm_id) {
+				uint32_t remaining_bw =
+					dp_tunnel_settings->estimated_bw - dp_tunnel_settings->allocated_bw;
+
+				router_sets[j].allocated_bw += dp_tunnel_settings->allocated_bw;
+
+				if (remaining_bw > router_sets[j].remaining_bw)
+					router_sets[j].remaining_bw = remaining_bw;
+
+				// Get the max estimated BW within the same CM_ID
+				if (dp_tunnel_settings->estimated_bw > router_sets[j].estimated_bw)
+					router_sets[j].estimated_bw = dp_tunnel_settings->estimated_bw;
+
+				router_sets[j].required_bw += link_bw_granularity;
+				router_sets[j].dpia_count++;
+				break;
+			}
+		}
+	}
+
+	// Validate bandwidth for each unique router found.
+	for (i = 0; i < router_count; i++) {
+		uint32_t total_bw = 0;
+
+		if (router_sets[i].is_valid == false)
+			break;
+
+		// Determine the total available bandwidth for the current router based on aggregated data
+		if ((router_sets[i].dpia_count == 1) || (router_sets[i].allocated_bw == 0))
+			total_bw = router_sets[i].estimated_bw;
+		else
+			total_bw = router_sets[i].allocated_bw + router_sets[i].remaining_bw;
+
+		if (router_sets[i].required_bw > total_bw) {
+			is_success = false;
+			break;
+		}
+	}
+
+	return is_success;
+}
+

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_dpia_bw.h

@@ -0,0 +1,112 @@
+/*
+ * Copyright 2021 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#ifndef DC_INC_LINK_DP_DPIA_BW_H_
+#define DC_INC_LINK_DP_DPIA_BW_H_
+
+#include "link_service.h"
+
+
+/*
+ * Host Router BW type
+ */
+enum bw_type {
+	HOST_ROUTER_BW_ESTIMATED,
+	HOST_ROUTER_BW_ALLOCATED,
+	HOST_ROUTER_BW_INVALID,
+};
+
+struct usb4_router_validation_set {
+	bool is_valid;
+	uint8_t cm_id;
+	uint8_t dpia_count;
+	uint32_t required_bw;
+	uint32_t allocated_bw;
+	uint32_t estimated_bw;
+	uint32_t remaining_bw;
+};
+
+/*
+ * Enable USB4 DP BW allocation mode
+ *
+ * @link: pointer to the dc_link struct instance
+ *
+ * return: SUCCESS or FAILURE
+ */
+bool link_dpia_enable_usb4_dp_bw_alloc_mode(struct dc_link *link);
+
+/*
+ * Allocates only what the stream needs for bw, so if:
+ * If (stream_req_bw < or > already_allocated_bw_at_HPD)
+ * => Deallocate Max Bw & then allocate only what the stream needs
+ *
+ * @link: pointer to the dc_link struct instance
+ * @req_bw: Bw requested by the stream
+ *
+ */
+void link_dp_dpia_allocate_usb4_bandwidth_for_stream(struct dc_link *link, int req_bw);
+
+/*
+ * Handle the USB4 BW Allocation related functionality here:
+ * Plug => Try to allocate max bw from timing parameters supported by the sink
+ * Unplug => de-allocate bw
+ *
+ * @link: pointer to the dc_link struct instance
+ * @peak_bw: Peak bw used by the link/sink
+ *
+ */
+void dpia_handle_usb4_bandwidth_allocation_for_link(struct dc_link *link, int peak_bw);
+
+/*
+ * Obtain all the DP overheads in dp tunneling for the dpia link
+ *
+ * @link: pointer to the dc_link struct instance
+ *
+ * return: DP overheads in DP tunneling
+ */
+uint32_t link_dpia_get_dp_overhead(const struct dc_link *link);
+
+/*
+ * Handle DP BW allocation status register
+ *
+ * @link: pointer to the dc_link struct instance
+ * @status: content of DP tunneling status register
+ *
+ * return: none
+ */
+void link_dp_dpia_handle_bw_alloc_status(struct dc_link *link, uint8_t status);
+
+/*
+ * Aggregates the DPIA bandwidth usage for the respective USB4 Router.
+ *
+ * @dc_validation_dpia_set: pointer to the dc_validation_dpia_set
+ * @count: number of DPIA validation sets
+ *
+ * return: true if validation is succeeded
+ */
+bool link_dpia_validate_dp_tunnel_bandwidth(const struct dc_validation_dpia_set *dpia_link_sets, uint8_t count);
+
+#endif /* DC_INC_LINK_DP_DPIA_BW_H_ */
+

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_irq_handler.c

@@ -0,0 +1,618 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+/* FILE POLICY AND INTENDED USAGE:
+ * This file implements DP HPD short pulse handling sequence according to DP
+ * specifications
+ *
+ */
+
+#include "link_dp_irq_handler.h"
+#include "link_dpcd.h"
+#include "link_dp_training.h"
+#include "link_dp_capability.h"
+#include "link_edp_panel_control.h"
+#include "link_dp_panel_replay.h"
+#include "link/accessories/link_dp_trace.h"
+#include "link/link_dpms.h"
+#include "dm_helpers.h"
+#include "link_dp_dpia_bw.h"
+#include "link_dp_panel_replay.h"
+
+#define DC_LOGGER \
+	link->ctx->logger
+#define DC_LOGGER_INIT(logger)
+
+bool dp_parse_link_loss_status(
+	struct dc_link *link,
+	union hpd_irq_data *hpd_irq_dpcd_data)
+{
+	uint8_t irq_reg_rx_power_state = 0;
+	enum dc_status dpcd_result = DC_ERROR_UNEXPECTED;
+	union lane_status lane_status;
+	uint32_t lane;
+	bool sink_status_changed;
+	bool return_code;
+
+	sink_status_changed = false;
+	return_code = false;
+
+	if (link->cur_link_settings.lane_count == 0)
+		return return_code;
+
+	/*1. Check that Link Status changed, before re-training.*/
+
+	/*parse lane status*/
+	for (lane = 0; lane < (uint32_t)link->cur_link_settings.lane_count; lane++) {
+		/* check status of lanes 0,1
+		 * changed DpcdAddress_Lane01Status (0x202)
+		 */
+		lane_status.raw = dp_get_nibble_at_index(
+			&hpd_irq_dpcd_data->bytes.lane01_status.raw,
+			lane);
+
+		if (!lane_status.bits.CHANNEL_EQ_DONE_0 ||
+			!lane_status.bits.CR_DONE_0 ||
+			!lane_status.bits.SYMBOL_LOCKED_0) {
+			/* if one of the channel equalization, clock
+			 * recovery or symbol lock is dropped
+			 * consider it as (link has been
+			 * dropped) dp sink status has changed
+			 */
+			sink_status_changed = true;
+			break;
+		}
+	}
+
+	/* Check interlane align.*/
+	if (link_dp_get_encoding_format(&link->cur_link_settings) == DP_128b_132b_ENCODING &&
+			(!hpd_irq_dpcd_data->bytes.lane_status_updated.bits.EQ_INTERLANE_ALIGN_DONE_128b_132b ||
+			 !hpd_irq_dpcd_data->bytes.lane_status_updated.bits.CDS_INTERLANE_ALIGN_DONE_128b_132b)) {
+		sink_status_changed = true;
+	} else if (!hpd_irq_dpcd_data->bytes.lane_status_updated.bits.INTERLANE_ALIGN_DONE) {
+		sink_status_changed = true;
+	}
+
+	if (sink_status_changed) {
+
+		DC_LOG_HW_HPD_IRQ("%s: Link Status changed.\n", __func__);
+
+		return_code = true;
+
+		/*2. Check that we can handle interrupt: Not in FS DOS,
+		 *  Not in "Display Timeout" state, Link is trained.
+		 */
+		dpcd_result = core_link_read_dpcd(link,
+			DP_SET_POWER,
+			&irq_reg_rx_power_state,
+			sizeof(irq_reg_rx_power_state));
+
+		if (dpcd_result != DC_OK) {
+			DC_LOG_HW_HPD_IRQ("%s: DPCD read failed to obtain power state.\n",
+				__func__);
+		} else {
+			if (irq_reg_rx_power_state != DP_SET_POWER_D0)
+				return_code = false;
+		}
+	}
+
+	return return_code;
+}
+
+static bool handle_hpd_irq_psr_sink(struct dc_link *link)
+{
+	union dpcd_psr_configuration psr_configuration = {0};
+
+	if (!link->psr_settings.psr_feature_enabled)
+		return false;
+
+	dm_helpers_dp_read_dpcd(
+		link->ctx,
+		link,
+		368,/*DpcdAddress_PSR_Enable_Cfg*/
+		&psr_configuration.raw,
+		sizeof(psr_configuration.raw));
+
+	if (psr_configuration.bits.ENABLE) {
+		unsigned char dpcdbuf[3] = {0};
+		union psr_error_status psr_error_status;
+		union psr_sink_psr_status psr_sink_psr_status;
+
+		dm_helpers_dp_read_dpcd(
+			link->ctx,
+			link,
+			0x2006, /*DpcdAddress_PSR_Error_Status*/
+			(unsigned char *) dpcdbuf,
+			sizeof(dpcdbuf));
+
+		/*DPCD 2006h   ERROR STATUS*/
+		psr_error_status.raw = dpcdbuf[0];
+		/*DPCD 2008h   SINK PANEL SELF REFRESH STATUS*/
+		psr_sink_psr_status.raw = dpcdbuf[2];
+
+		if (psr_error_status.bits.LINK_CRC_ERROR ||
+				psr_error_status.bits.RFB_STORAGE_ERROR ||
+				psr_error_status.bits.VSC_SDP_ERROR) {
+			bool allow_active;
+
+			/* Acknowledge and clear error bits */
+			dm_helpers_dp_write_dpcd(
+				link->ctx,
+				link,
+				8198,/*DpcdAddress_PSR_Error_Status*/
+				&psr_error_status.raw,
+				sizeof(psr_error_status.raw));
+
+			/* PSR error, disable and re-enable PSR */
+			if (link->psr_settings.psr_allow_active) {
+				allow_active = false;
+				edp_set_psr_allow_active(link, &allow_active, true, false, NULL);
+				allow_active = true;
+				edp_set_psr_allow_active(link, &allow_active, true, false, NULL);
+			}
+
+			return true;
+		} else if (psr_sink_psr_status.bits.SINK_SELF_REFRESH_STATUS ==
+				PSR_SINK_STATE_ACTIVE_DISPLAY_FROM_SINK_RFB){
+			/* No error is detect, PSR is active.
+			 * We should return with IRQ_HPD handled without
+			 * checking for loss of sync since PSR would have
+			 * powered down main link.
+			 */
+			return true;
+		}
+	}
+	return false;
+}
+
+static void handle_hpd_irq_vesa_replay_sink(struct dc_link *link)
+{
+	union pr_error_status pr_error_status = {0};
+
+	if (!link->replay_settings.replay_feature_enabled ||
+			link->replay_settings.config.replay_version != DC_VESA_PANEL_REPLAY)
+		return;
+
+	dm_helpers_dp_read_dpcd(
+		link->ctx,
+		link,
+		DP_PR_ERROR_STATUS,
+		&pr_error_status.raw,
+		sizeof(pr_error_status.raw));
+
+	if (pr_error_status.bits.LINK_CRC_ERROR ||
+			pr_error_status.bits.RFB_STORAGE_ERROR ||
+			pr_error_status.bits.VSC_SDP_ERROR ||
+			pr_error_status.bits.ASSDP_MISSING_ERROR) {
+
+		/* Acknowledge and clear error bits */
+		dm_helpers_dp_write_dpcd(
+			link->ctx,
+			link,
+			DP_PR_ERROR_STATUS, /*DpcdAddress_PR_Error_Status*/
+			&pr_error_status.raw,
+			sizeof(pr_error_status.raw));
+
+		/* Replay error, disable and re-enable Replay */
+		if (link->replay_settings.replay_allow_active) {
+			dp_pr_enable(link, false);
+			dp_pr_enable(link, true);
+		}
+	}
+}
+
+static void handle_hpd_irq_replay_sink(struct dc_link *link, bool *need_re_enable, bool *replay_esd_detection_needed)
+{
+	union dpcd_replay_configuration replay_configuration = {0};
+	union dpcd_replay_configuration replay_sink_status = {0};
+	/*AMD Replay version reuse DP_PSR_ERROR_STATUS for REPLAY_ERROR status.*/
+	union psr_error_status replay_error_status = {0};
+	bool ret = false;
+	int retries = 0;
+
+	if (!link->replay_settings.replay_feature_enabled)
+		return;
+
+	if (link->replay_settings.config.replay_version != DC_FREESYNC_REPLAY) {
+		handle_hpd_irq_vesa_replay_sink(link);
+		return;
+	}
+
+	while (retries < 10) {
+		ret = dm_helpers_dp_read_dpcd(
+			link->ctx,
+			link,
+			DP_SINK_PR_REPLAY_STATUS,
+			&replay_configuration.raw,
+			sizeof(replay_configuration.raw));
+
+		if (ret)
+			break;
+
+		retries++;
+	}
+
+	if (!ret)
+		DC_LOG_WARNING("[%s][%d] DPCD read addr.0x%x failed with %d retries\n",
+					__func__, __LINE__,
+					DP_SINK_PR_REPLAY_STATUS, retries);
+
+	dm_helpers_dp_read_dpcd(
+		link->ctx,
+		link,
+		DP_PSR_ERROR_STATUS,
+		&replay_error_status.raw,
+		sizeof(replay_error_status.raw));
+
+	dm_helpers_dp_read_dpcd(
+		link->ctx,
+		link,
+		DP_PR_REPLAY_SINK_STATUS,
+		&replay_sink_status.raw,
+		1);
+
+	if (replay_error_status.bits.LINK_CRC_ERROR ||
+		replay_configuration.bits.DESYNC_ERROR_STATUS ||
+		replay_configuration.bits.STATE_TRANSITION_ERROR_STATUS ||
+		replay_sink_status.bits.SINK_DEVICE_REPLAY_STATUS == 0x7) {
+		bool allow_active;
+
+		link->replay_settings.config.replay_error_status.raw |= replay_error_status.raw;
+
+		/* Increment desync error counter if a desync error is detected */
+		if (replay_configuration.bits.DESYNC_ERROR_STATUS)
+			link->replay_settings.replay_desync_error_fail_count++;
+
+		if (link->replay_settings.config.force_disable_desync_error_check)
+			return;
+
+		/* Acknowledge and clear configuration bits */
+		dm_helpers_dp_write_dpcd(
+			link->ctx,
+			link,
+			DP_SINK_PR_REPLAY_STATUS,
+			&replay_configuration.raw,
+			sizeof(replay_configuration.raw));
+
+		/* Acknowledge and clear error bits */
+		dm_helpers_dp_write_dpcd(
+			link->ctx,
+			link,
+			DP_PSR_ERROR_STATUS,/*DpcdAddress_REPLAY_Error_Status*/
+			&replay_error_status.raw,
+			sizeof(replay_error_status.raw));
+
+		/* Replay error, disable and re-enable Replay */
+		if (link->replay_settings.replay_allow_active) {
+			allow_active = false;
+			edp_set_replay_allow_active(link, &allow_active, true, false, NULL);
+			*need_re_enable = true;
+		}
+	}
+
+	if (link->ctx->dc->debug.enable_replay_esd_recovery) {
+		if (!link->replay_settings.replay_allow_active &&
+		    replay_sink_status.bits.SINK_DEVICE_REPLAY_STATUS == 0x7) {
+		    /* If sink device replay status is 0x7 and replay is disabled,
+		     * it means sink is in a bad state and link retraining is needed to recover
+		     */
+		    *replay_esd_detection_needed = true;
+		}
+	}
+}
+
+void dp_handle_link_loss(struct dc_link *link)
+{
+	struct pipe_ctx *pipes[MAX_PIPES];
+	struct dc_state *state = link->dc->current_state;
+	uint8_t count;
+	int i;
+
+	link_get_master_pipes_with_dpms_on(link, state, &count, pipes);
+
+	for (i = 0; i < count; i++)
+		link_set_dpms_off(pipes[i]);
+
+	for (i = count - 1; i >= 0; i--) {
+		// Always use max settings here for DP 1.4a LL Compliance CTS
+		if (link->skip_fallback_on_link_loss) {
+			pipes[i]->link_config.dp_link_settings.lane_count =
+					link->verified_link_cap.lane_count;
+			pipes[i]->link_config.dp_link_settings.link_rate =
+					link->verified_link_cap.link_rate;
+			pipes[i]->link_config.dp_link_settings.link_spread =
+					link->verified_link_cap.link_spread;
+		}
+		link_set_dpms_on(link->dc->current_state, pipes[i]);
+	}
+}
+
+static void dp_handle_tunneling_irq(struct dc_link *link)
+{
+	enum dc_status retval;
+	uint8_t tunneling_status = 0;
+
+	retval = core_link_read_dpcd(
+			link, DP_TUNNELING_STATUS,
+			&tunneling_status,
+			sizeof(tunneling_status));
+
+	if (retval == DC_OK) {
+		DC_LOG_HW_HPD_IRQ("%s: Got DP tunneling status on link %d status=0x%x",
+				__func__, link->link_index, tunneling_status);
+
+		if (tunneling_status & DP_TUNNELING_BW_ALLOC_BITS_MASK)
+			link_dp_dpia_handle_bw_alloc_status(link, tunneling_status);
+	}
+
+	tunneling_status = DP_TUNNELING_IRQ;
+	core_link_write_dpcd(
+		link, DP_LINK_SERVICE_IRQ_VECTOR_ESI0,
+		&tunneling_status, 1);
+}
+
+static void read_dpcd204h_on_irq_hpd(struct dc_link *link, union hpd_irq_data *irq_data)
+{
+	enum dc_status retval;
+	union lane_align_status_updated dpcd_lane_status_updated = {0};
+
+	retval = core_link_read_dpcd(
+			link,
+			DP_LANE_ALIGN_STATUS_UPDATED,
+			&dpcd_lane_status_updated.raw,
+			sizeof(union lane_align_status_updated));
+
+	if (retval == DC_OK) {
+		irq_data->bytes.lane_status_updated.bits.EQ_INTERLANE_ALIGN_DONE_128b_132b =
+				dpcd_lane_status_updated.bits.EQ_INTERLANE_ALIGN_DONE_128b_132b;
+		irq_data->bytes.lane_status_updated.bits.CDS_INTERLANE_ALIGN_DONE_128b_132b =
+				dpcd_lane_status_updated.bits.CDS_INTERLANE_ALIGN_DONE_128b_132b;
+	}
+}
+
+enum dc_status dp_read_hpd_rx_irq_data(
+	struct dc_link *link,
+	union hpd_irq_data *irq_data)
+{
+	static enum dc_status retval;
+
+	/* The HW reads 16 bytes from 200h on HPD,
+	 * but if we get an AUX_DEFER, the HW cannot retry
+	 * and this causes the CTS tests 4.3.2.1 - 3.2.4 to
+	 * fail, so we now explicitly read 6 bytes which is
+	 * the req from the above mentioned test cases.
+	 *
+	 * For DP 1.4 we need to read those from 2002h range.
+	 */
+	if (link->dpcd_caps.dpcd_rev.raw < DPCD_REV_14) {
+		retval = core_link_read_dpcd(
+			link,
+			DP_SINK_COUNT,
+			irq_data->raw,
+			DP_SINK_STATUS - DP_SINK_COUNT + 1);
+
+		if (link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dp_tunneling) {
+			retval = core_link_read_dpcd(
+					link, DP_LINK_SERVICE_IRQ_VECTOR_ESI0,
+					&irq_data->bytes.link_service_irq_esi0.raw, 1);
+		}
+	} else {
+		/* Read 14 bytes in a single read and then copy only the required fields.
+		 * This is more efficient than doing it in two separate AUX reads. */
+
+		uint8_t tmp[DP_SINK_STATUS_ESI - DP_SINK_COUNT_ESI + 1] = {0};
+
+		retval = core_link_read_dpcd(
+			link,
+			DP_SINK_COUNT_ESI,
+			tmp,
+			sizeof(tmp));
+
+		if (retval != DC_OK)
+			return retval;
+
+		irq_data->bytes.sink_cnt.raw = tmp[DP_SINK_COUNT_ESI - DP_SINK_COUNT_ESI];
+		irq_data->bytes.device_service_irq.raw = tmp[DP_DEVICE_SERVICE_IRQ_VECTOR_ESI0 - DP_SINK_COUNT_ESI];
+		irq_data->bytes.lane01_status.raw = tmp[DP_LANE0_1_STATUS_ESI - DP_SINK_COUNT_ESI];
+		irq_data->bytes.lane23_status.raw = tmp[DP_LANE2_3_STATUS_ESI - DP_SINK_COUNT_ESI];
+		irq_data->bytes.lane_status_updated.raw = tmp[DP_LANE_ALIGN_STATUS_UPDATED_ESI - DP_SINK_COUNT_ESI];
+		irq_data->bytes.sink_status.raw = tmp[DP_SINK_STATUS_ESI - DP_SINK_COUNT_ESI];
+		irq_data->bytes.link_service_irq_esi0.raw = tmp[DP_LINK_SERVICE_IRQ_VECTOR_ESI0 - DP_SINK_COUNT_ESI];
+
+		/*
+		 * This display doesn't have correct values in DPCD200Eh.
+		 * Read and check DPCD204h instead.
+		 */
+		if (link->wa_flags.read_dpcd204h_on_irq_hpd)
+			read_dpcd204h_on_irq_hpd(link, irq_data);
+	}
+
+	return retval;
+}
+
+/*************************Short Pulse IRQ***************************/
+bool dp_should_allow_hpd_rx_irq(const struct dc_link *link)
+{
+	/*
+	 * Don't handle RX IRQ unless one of following is met:
+	 * 1) The link is established (cur_link_settings != unknown)
+	 * 2) We know we're dealing with a branch device, SST or MST
+	 * 3) The link is bw_alloc enabled.
+	 */
+
+	if ((link->cur_link_settings.lane_count != LANE_COUNT_UNKNOWN) ||
+		is_dp_branch_device(link) ||
+		link->dpia_bw_alloc_config.bw_alloc_enabled)
+		return true;
+
+	return false;
+}
+
+bool dp_handle_hpd_rx_irq(struct dc_link *link,
+		union hpd_irq_data *out_hpd_irq_dpcd_data, bool *out_link_loss,
+		bool defer_handling, bool *has_left_work)
+{
+	union hpd_irq_data hpd_irq_dpcd_data = {0};
+	union device_service_irq device_service_clear = {0};
+	enum dc_status result;
+	bool status = false;
+	bool replay_re_enable_needed = false;
+	bool replay_esd_detection_needed = false;
+
+	if (out_link_loss)
+		*out_link_loss = false;
+
+	if (has_left_work)
+		*has_left_work = false;
+	/* For use cases related to down stream connection status change,
+	 * PSR and device auto test, refer to function handle_sst_hpd_irq
+	 * in DAL2.1*/
+
+	DC_LOG_HW_HPD_IRQ("%s: Got short pulse HPD on link %d\n",
+		__func__, link->link_index);
+
+	handle_hpd_irq_replay_sink(link, &replay_re_enable_needed, &replay_esd_detection_needed);
+
+	 /* All the "handle_hpd_irq_xxx()" methods
+		 * should be called only after
+		 * dal_dpsst_ls_read_hpd_irq_data
+		 * Order of calls is important too
+		 */
+	result = dp_read_hpd_rx_irq_data(link, &hpd_irq_dpcd_data);
+	if (out_hpd_irq_dpcd_data)
+		*out_hpd_irq_dpcd_data = hpd_irq_dpcd_data;
+
+	if (result != DC_OK) {
+		DC_LOG_HW_HPD_IRQ("%s: DPCD read failed to obtain irq data\n",
+			__func__);
+		return false;
+	}
+
+	if (hpd_irq_dpcd_data.bytes.device_service_irq.bits.AUTOMATED_TEST) {
+		// Workaround for DP 1.4a LL Compliance CTS as USB4 has to share encoders unlike DP and USBC
+		if (link->ep_type == DISPLAY_ENDPOINT_USB4_DPIA &&
+				!link->dc->config.enable_dpia_pre_training)
+			link->skip_fallback_on_link_loss = true;
+
+		device_service_clear.bits.AUTOMATED_TEST = 1;
+		core_link_write_dpcd(
+			link,
+			DP_DEVICE_SERVICE_IRQ_VECTOR,
+			&device_service_clear.raw,
+			sizeof(device_service_clear.raw));
+		device_service_clear.raw = 0;
+		if (defer_handling && has_left_work)
+			*has_left_work = true;
+		else
+			dc_link_dp_handle_automated_test(link);
+		return false;
+	}
+
+	if (!dp_should_allow_hpd_rx_irq(link)) {
+		DC_LOG_HW_HPD_IRQ("%s: skipping HPD handling on %d\n",
+			__func__, link->link_index);
+		return false;
+	}
+
+	if (handle_hpd_irq_psr_sink(link))
+		/* PSR-related error was detected and handled */
+		return true;
+
+	/* If PSR-related error handled, Main link may be off,
+	 * so do not handle as a normal sink status change interrupt.
+	 */
+
+	if (hpd_irq_dpcd_data.bytes.device_service_irq.bits.UP_REQ_MSG_RDY) {
+		if (defer_handling && has_left_work)
+			*has_left_work = true;
+		return true;
+	}
+
+	/* check if we have MST msg and return since we poll for it */
+	if (hpd_irq_dpcd_data.bytes.device_service_irq.bits.DOWN_REP_MSG_RDY) {
+		if (defer_handling && has_left_work)
+			*has_left_work = true;
+		return false;
+	}
+
+	/* Handle 'Downstream port status' case for all DP link types.
+	 * If we got sink count changed it means
+	 * Downstream port status changed,
+	 * then DM should call DC to do the detection.
+	 * NOTE: Now includes eDP link loss detection and retraining
+	 * Link will be retrained if panel is not EDP or
+	 * Replay ESD recovery is needed.
+	 */
+	if (link->connector_signal != SIGNAL_TYPE_EDP || replay_esd_detection_needed) {
+		if (dp_parse_link_loss_status(
+				link,
+				&hpd_irq_dpcd_data)) {
+			/* Connectivity log: link loss */
+			CONN_DATA_LINK_LOSS(link,
+						hpd_irq_dpcd_data.raw,
+						sizeof(hpd_irq_dpcd_data),
+						"Status: ");
+
+			if (defer_handling && has_left_work)
+				*has_left_work = true;
+			else
+				dp_handle_link_loss(link);
+
+			status = false;
+			if (out_link_loss)
+				*out_link_loss = true;
+
+			dp_trace_link_loss_increment(link);
+		}
+	}
+
+	if (link->dpcd_caps.usb4_dp_tun_info.dp_tun_cap.bits.dp_tunneling) {
+		if (hpd_irq_dpcd_data.bytes.link_service_irq_esi0.bits.DP_LINK_TUNNELING_IRQ)
+			dp_handle_tunneling_irq(link);
+	}
+
+	if (link->type == dc_connection_sst_branch &&
+		hpd_irq_dpcd_data.bytes.sink_cnt.bits.SINK_COUNT
+			!= link->dpcd_sink_count)
+		status = true;
+
+	if (replay_re_enable_needed) {
+		bool allow_active = true;
+
+		edp_set_replay_allow_active(link, &allow_active, true, false, NULL);
+	}
+	/* reasons for HPD RX:
+	 * 1. Link Loss - ie Re-train the Link
+	 * 2. MST sideband message
+	 * 3. Automated Test - ie. Internal Commit
+	 * 4. CP (copy protection) - (not interesting for DM???)
+	 * 5. DRR
+	 * 6. Downstream Port status changed
+	 * -ie. Detect - this the only one
+	 * which is interesting for DM because
+	 * it must call dc_link_detect.
+	 */
+	return status;
+}

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_irq_handler.h

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#ifndef __DC_LINK_DP_IRQ_HANDLER_H__
+#define __DC_LINK_DP_IRQ_HANDLER_H__
+
+#include "link_service.h"
+bool dp_parse_link_loss_status(
+	struct dc_link *link,
+	union hpd_irq_data *hpd_irq_dpcd_data);
+bool dp_should_allow_hpd_rx_irq(const struct dc_link *link);
+void dp_handle_link_loss(struct dc_link *link);
+enum dc_status dp_read_hpd_rx_irq_data(
+	struct dc_link *link,
+	union hpd_irq_data *irq_data);
+bool dp_handle_hpd_rx_irq(struct dc_link *link,
+		union hpd_irq_data *out_hpd_irq_dpcd_data, bool *out_link_loss,
+		bool defer_handling, bool *has_left_work);
+#endif /* __DC_LINK_DP_IRQ_HANDLER_H__ */

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_panel_replay.c

@@ -0,0 +1,428 @@
+/*
+ * Copyright 2025 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#include "link_dp_panel_replay.h"
+#include "link_edp_panel_control.h"
+#include "link_dpcd.h"
+#include "dm_helpers.h"
+#include "dc/dc_dmub_srv.h"
+#include "dce/dmub_replay.h"
+
+#define DC_LOGGER \
+	link->ctx->logger
+
+#define DP_SINK_PR_ENABLE_AND_CONFIGURATION		0x37B
+#define DP_SINK_ENABLE_FRAME_SKIPPING_MODE_SHIFT	(5)
+
+static unsigned int dp_pr_calc_num_static_frames(unsigned int vsync_rate_hz)
+{
+	// at least 2 frames for static screen
+	unsigned int num_frames = 2;
+
+	// get number of frames for at least 50ms
+	if (vsync_rate_hz > 40)
+		num_frames = (vsync_rate_hz + 10) / 20;
+
+	return num_frames;
+}
+
+static void dp_pr_set_static_screen_param(struct dc_link *link)
+{
+	struct dc_static_screen_params params = {0};
+	struct dc *dc = link->ctx->dc;
+	// only support DP sst for now
+	if (!dc_is_dp_sst_signal(link->connector_signal))
+		return;
+
+	for (int i = 0; i < MAX_PIPES; i++) {
+		if (dc->current_state->res_ctx.pipe_ctx[i].stream &&
+			dc->current_state->res_ctx.pipe_ctx[i].stream->link == link) {
+			struct dc_stream_state *stream = dc->current_state->res_ctx.pipe_ctx[i].stream;
+			unsigned int vsync_rate_hz = (unsigned int)div64_u64(div64_u64(
+														(stream->timing.pix_clk_100hz * (u64)100),
+														stream->timing.v_total),
+														stream->timing.h_total);
+			params.triggers.cursor_update = true;
+			params.triggers.overlay_update = true;
+			params.triggers.surface_update = true;
+			params.num_frames = dp_pr_calc_num_static_frames(vsync_rate_hz);
+
+			dc_stream_set_static_screen_params(dc, &stream, 1, &params);
+			break;
+		}
+	}
+}
+
+static bool dp_setup_panel_replay(struct dc_link *link, const struct dc_stream_state *stream)
+{
+	/* To-do: Setup Replay */
+	struct dc *dc;
+	struct dmub_replay *replay;
+	int i;
+	unsigned int panel_inst;
+	struct replay_context replay_context = { 0 };
+	unsigned int lineTimeInNs = 0;
+
+	union panel_replay_enable_and_configuration_1 pr_config_1 = { 0 };
+	union panel_replay_enable_and_configuration_2 pr_config_2 = { 0 };
+
+	union dpcd_alpm_configuration alpm_config;
+	uint8_t data = 0;
+
+	replay_context.controllerId = CONTROLLER_ID_UNDEFINED;
+
+	if (!link)
+		return false;
+
+	//Clear Panel Replay enable & config
+	dm_helpers_dp_write_dpcd(link->ctx, link,
+		DP_PANEL_REPLAY_ENABLE_AND_CONFIGURATION_1,
+		(uint8_t *)&(pr_config_1.raw), sizeof(uint8_t));
+
+	dm_helpers_dp_write_dpcd(link->ctx, link,
+		DP_PANEL_REPLAY_ENABLE_AND_CONFIGURATION_2,
+		(uint8_t *)&(pr_config_2.raw), sizeof(uint8_t));
+
+	if (!(link->replay_settings.config.replay_supported))
+		return false;
+
+	dc = link->ctx->dc;
+
+	//not sure should keep or not
+	replay = dc->res_pool->replay;
+
+	if (!replay)
+		return false;
+
+	if (!dp_pr_get_panel_inst(dc, link, &panel_inst))
+		return false;
+
+	replay_context.aux_inst = link->ddc->ddc_pin->hw_info.ddc_channel;
+	replay_context.digbe_inst = link->link_enc->transmitter;
+	replay_context.digfe_inst = link->link_enc->preferred_engine;
+
+	for (i = 0; i < MAX_PIPES; i++) {
+		if (dc->current_state->res_ctx.pipe_ctx[i].stream
+				== stream) {
+			/* dmcu -1 for all controller id values,
+			 * therefore +1 here
+			 */
+			replay_context.controllerId =
+				dc->current_state->res_ctx.pipe_ctx[i].stream_res.tg->inst + 1;
+			break;
+		}
+	}
+
+	lineTimeInNs =
+		((stream->timing.h_total * 1000000) /
+			(stream->timing.pix_clk_100hz / 10)) + 1;
+
+	replay_context.line_time_in_ns = lineTimeInNs;
+
+	link->replay_settings.replay_feature_enabled = dp_pr_copy_settings(link, &replay_context);
+
+	if (link->replay_settings.replay_feature_enabled) {
+		if (dc_is_embedded_signal(link->connector_signal)) {
+			pr_config_1.bits.PANEL_REPLAY_ENABLE = 1;
+			pr_config_1.bits.PANEL_REPLAY_CRC_ENABLE = 1;
+			pr_config_1.bits.IRQ_HPD_ASSDP_MISSING = 1;
+			pr_config_1.bits.IRQ_HPD_VSCSDP_UNCORRECTABLE_ERROR = 1;
+			pr_config_1.bits.IRQ_HPD_RFB_ERROR = 1;
+			pr_config_1.bits.IRQ_HPD_ACTIVE_FRAME_CRC_ERROR = 1;
+			pr_config_1.bits.PANEL_REPLAY_SELECTIVE_UPDATE_ENABLE = 1;
+			pr_config_1.bits.PANEL_REPLAY_EARLY_TRANSPORT_ENABLE = 1;
+		} else {
+			pr_config_1.bits.PANEL_REPLAY_ENABLE = 1;
+		}
+
+		pr_config_2.bits.SINK_REFRESH_RATE_UNLOCK_GRANTED = 0;
+
+		if (link->dpcd_caps.vesa_replay_caps.bits.SU_Y_GRANULARITY_EXT_CAP_SUPPORTED)
+			pr_config_2.bits.SU_Y_GRANULARITY_EXT_VALUE_ENABLED = 1;
+
+		pr_config_2.bits.SU_REGION_SCAN_LINE_CAPTURE_INDICATION = 0;
+
+		dm_helpers_dp_write_dpcd(link->ctx, link,
+			DP_PANEL_REPLAY_ENABLE_AND_CONFIGURATION_1,
+			(uint8_t *)&(pr_config_1.raw), sizeof(uint8_t));
+
+		dm_helpers_dp_write_dpcd(link->ctx, link,
+			DP_PANEL_REPLAY_ENABLE_AND_CONFIGURATION_2,
+			(uint8_t *)&(pr_config_2.raw), sizeof(uint8_t));
+
+		//ALPM Setup
+		memset(&alpm_config, 0, sizeof(alpm_config));
+		alpm_config.bits.ENABLE = link->replay_settings.config.alpm_mode != DC_ALPM_UNSUPPORTED ? 1 : 0;
+
+		if (link->replay_settings.config.alpm_mode == DC_ALPM_AUXLESS) {
+			alpm_config.bits.ALPM_MODE_SEL = 1;
+			alpm_config.bits.ACDS_PERIOD_DURATION = 1;
+		}
+
+		dm_helpers_dp_write_dpcd(
+			link->ctx,
+			link,
+			DP_RECEIVER_ALPM_CONFIG,
+			&alpm_config.raw,
+			sizeof(alpm_config.raw));
+
+		//Enable frame skipping
+		if (link->replay_settings.config.frame_skip_supported)
+			data = data | (1 << DP_SINK_ENABLE_FRAME_SKIPPING_MODE_SHIFT);
+
+		dm_helpers_dp_write_dpcd(link->ctx, link,
+			DP_SINK_PR_ENABLE_AND_CONFIGURATION,
+			(uint8_t *)&(data), sizeof(uint8_t));
+	}
+
+	return true;
+}
+
+
+bool dp_pr_get_panel_inst(const struct dc *dc,
+		const struct dc_link *link,
+		unsigned int *inst_out)
+{
+	if (!dc || !link || !inst_out)
+		return false;
+
+	if (dc->config.frame_update_cmd_version2 == false)
+		return dc_get_edp_link_panel_inst(dc, link, inst_out);
+
+	if (!dc_is_dp_sst_signal(link->connector_signal)) /* only supoprt DP sst (eDP included) for now */
+		return false;
+
+	for (unsigned int i = 0; i < MAX_PIPES; i++) {
+		if (dc->current_state->res_ctx.pipe_ctx[i].stream &&
+			dc->current_state->res_ctx.pipe_ctx[i].stream->link == link) {
+			/* *inst_out is equal to otg number */
+			if (dc->current_state->res_ctx.pipe_ctx[i].stream_res.tg)
+				*inst_out = dc->current_state->res_ctx.pipe_ctx[i].stream_res.tg->inst;
+			else
+				*inst_out = 0;
+
+			return true;
+		}
+	}
+
+	return false;
+}
+
+bool dp_setup_replay(struct dc_link *link, const struct dc_stream_state *stream)
+{
+	if (!link)
+		return false;
+	if (link->replay_settings.config.replay_version == DC_VESA_PANEL_REPLAY)
+		return dp_setup_panel_replay(link, stream);
+	else if (link->replay_settings.config.replay_version == DC_FREESYNC_REPLAY)
+		return edp_setup_freesync_replay(link, stream);
+	else
+		return false;
+}
+
+bool dp_pr_enable(struct dc_link *link, bool enable)
+{
+	struct dc *dc = link->ctx->dc;
+	unsigned int panel_inst = 0;
+	union dmub_rb_cmd cmd;
+
+	if (!dp_pr_get_panel_inst(dc, link, &panel_inst))
+		return false;
+
+	if (link->replay_settings.replay_allow_active == enable)
+		return true;
+
+	if (enable && !dc_is_embedded_signal(link->connector_signal))
+		dp_pr_set_static_screen_param(link);
+
+	// for sending PR enable commands to DMUB
+	memset(&cmd, 0, sizeof(cmd));
+
+	cmd.pr_enable.header.type = DMUB_CMD__PR;
+	cmd.pr_enable.header.sub_type = DMUB_CMD__PR_ENABLE;
+	cmd.pr_enable.header.payload_bytes = sizeof(struct dmub_cmd_pr_enable_data);
+	cmd.pr_enable.data.panel_inst = (uint8_t)panel_inst;
+	cmd.pr_enable.data.enable = enable ? 1 : 0;
+	dc_wake_and_execute_dmub_cmd(dc->ctx, &cmd, DM_DMUB_WAIT_TYPE_WAIT);
+
+	link->replay_settings.replay_allow_active = enable;
+
+	return true;
+}
+
+bool dp_pr_copy_settings(struct dc_link *link, struct replay_context *replay_context)
+{
+	struct dc *dc = link->ctx->dc;
+	unsigned int panel_inst = 0;
+	union dmub_rb_cmd cmd;
+	struct pipe_ctx *pipe_ctx = NULL;
+
+	if (!dp_pr_get_panel_inst(dc, link, &panel_inst))
+		return false;
+
+	for (unsigned int i = 0; i < MAX_PIPES; i++) {
+		if (dc->current_state->res_ctx.pipe_ctx[i].stream &&
+			dc->current_state->res_ctx.pipe_ctx[i].stream->link &&
+			dc->current_state->res_ctx.pipe_ctx[i].stream->link == link &&
+			dc_is_dp_sst_signal(dc->current_state->res_ctx.pipe_ctx[i].stream->link->connector_signal)) {
+			pipe_ctx = &dc->current_state->res_ctx.pipe_ctx[i];
+			/* todo: need update for MST */
+			break;
+		}
+	}
+
+	if (!pipe_ctx)
+		return false;
+
+	memset(&cmd, 0, sizeof(cmd));
+	cmd.pr_copy_settings.header.type = DMUB_CMD__PR;
+	cmd.pr_copy_settings.header.sub_type = DMUB_CMD__PR_COPY_SETTINGS;
+	cmd.pr_copy_settings.header.payload_bytes = sizeof(struct dmub_cmd_pr_copy_settings_data);
+	cmd.pr_copy_settings.data.panel_inst = (uint8_t)panel_inst;
+	// HW inst
+	cmd.pr_copy_settings.data.aux_inst = replay_context->aux_inst;
+	cmd.pr_copy_settings.data.digbe_inst = replay_context->digbe_inst;
+	cmd.pr_copy_settings.data.digfe_inst = replay_context->digfe_inst;
+	if (pipe_ctx->plane_res.dpp)
+		cmd.pr_copy_settings.data.dpp_inst = (uint8_t)pipe_ctx->plane_res.dpp->inst;
+	else
+		cmd.pr_copy_settings.data.dpp_inst = 0;
+	if (pipe_ctx->stream_res.tg)
+		cmd.pr_copy_settings.data.otg_inst = (uint8_t)pipe_ctx->stream_res.tg->inst;
+	else
+		cmd.pr_copy_settings.data.otg_inst = 0;
+
+	cmd.pr_copy_settings.data.dpphy_inst = link->link_enc->transmitter;
+
+	cmd.pr_copy_settings.data.line_time_in_ns = replay_context->line_time_in_ns;
+	cmd.pr_copy_settings.data.flags.bitfields.fec_enable_status = (link->fec_state == dc_link_fec_enabled);
+	cmd.pr_copy_settings.data.flags.bitfields.dsc_enable_status = (pipe_ctx->stream->timing.flags.DSC == 1);
+	cmd.pr_copy_settings.data.debug.u32All = link->replay_settings.config.debug_flags;
+
+	// ALPM settings
+	cmd.pr_copy_settings.data.flags.bitfields.alpm_mode = (enum dmub_alpm_mode)link->replay_settings.config.alpm_mode;
+	if (link->replay_settings.config.alpm_mode == DC_ALPM_AUXLESS) {
+		cmd.pr_copy_settings.data.auxless_alpm_data.lfps_setup_ns = (uint16_t)dc->debug.auxless_alpm_lfps_setup_ns;
+		cmd.pr_copy_settings.data.auxless_alpm_data.lfps_period_ns = (uint16_t)dc->debug.auxless_alpm_lfps_period_ns;
+		cmd.pr_copy_settings.data.auxless_alpm_data.lfps_silence_ns = (uint16_t)dc->debug.auxless_alpm_lfps_silence_ns;
+		cmd.pr_copy_settings.data.auxless_alpm_data.lfps_t1_t2_override_us =
+			(uint16_t)dc->debug.auxless_alpm_lfps_t1t2_us;
+		cmd.pr_copy_settings.data.auxless_alpm_data.lfps_t1_t2_offset_us =
+			(uint16_t)dc->debug.auxless_alpm_lfps_t1t2_offset_us;
+		cmd.pr_copy_settings.data.auxless_alpm_data.lttpr_count = link->dc->link_srv->dp_get_lttpr_count(link);
+	}
+
+	cmd.pr_copy_settings.data.su_granularity_needed = link->dpcd_caps.vesa_replay_caps.bits.PR_SU_GRANULARITY_NEEDED;
+	cmd.pr_copy_settings.data.su_x_granularity = link->dpcd_caps.vesa_replay_su_info.pr_su_x_granularity;
+	cmd.pr_copy_settings.data.su_y_granularity = link->dpcd_caps.vesa_replay_su_info.pr_su_y_granularity;
+	cmd.pr_copy_settings.data.su_y_granularity_extended_caps =
+		link->dpcd_caps.vesa_replay_su_info.pr_su_y_granularity_extended_caps;
+
+	if (pipe_ctx->stream->timing.dsc_cfg.num_slices_v > 0)
+		cmd.pr_copy_settings.data.dsc_slice_height = (uint16_t)((pipe_ctx->stream->timing.v_addressable +
+			pipe_ctx->stream->timing.v_border_top + pipe_ctx->stream->timing.v_border_bottom) /
+			pipe_ctx->stream->timing.dsc_cfg.num_slices_v);
+
+	if (dc_is_embedded_signal(link->connector_signal))
+		cmd.pr_copy_settings.data.main_link_activity_option = OPTION_1C;
+	else
+		// For external DP, use option 1-A
+		cmd.pr_copy_settings.data.main_link_activity_option = OPTION_1A;
+
+	dc_wake_and_execute_dmub_cmd(dc->ctx, &cmd, DM_DMUB_WAIT_TYPE_WAIT);
+	return true;
+}
+
+bool dp_pr_update_state(struct dc_link *link, struct dmub_cmd_pr_update_state_data *update_state_data)
+{
+	struct dc *dc = link->ctx->dc;
+	unsigned int panel_inst = 0;
+	union dmub_rb_cmd cmd;
+
+	if (!dp_pr_get_panel_inst(dc, link, &panel_inst))
+		return false;
+
+	memset(&cmd, 0, sizeof(cmd));
+	memcpy(&cmd.pr_update_state.data, update_state_data, sizeof(struct dmub_cmd_pr_update_state_data));
+
+	cmd.pr_update_state.header.type = DMUB_CMD__PR;
+	cmd.pr_update_state.header.sub_type = DMUB_CMD__PR_UPDATE_STATE;
+	cmd.pr_update_state.header.payload_bytes = sizeof(struct dmub_cmd_pr_update_state_data);
+	cmd.pr_update_state.data.panel_inst = (uint8_t)panel_inst;
+
+	dc_wake_and_execute_dmub_cmd(dc->ctx, &cmd, DM_DMUB_WAIT_TYPE_WAIT);
+	return true;
+}
+
+bool dp_pr_set_general_cmd(struct dc_link *link, struct dmub_cmd_pr_general_cmd_data *general_cmd_data)
+{
+	struct dc *dc = link->ctx->dc;
+	unsigned int panel_inst = 0;
+	union dmub_rb_cmd cmd;
+
+	if (!dp_pr_get_panel_inst(dc, link, &panel_inst))
+		return false;
+
+	memset(&cmd, 0, sizeof(cmd));
+	memcpy(&cmd.pr_general_cmd.data, general_cmd_data, sizeof(struct dmub_cmd_pr_general_cmd_data));
+
+	cmd.pr_general_cmd.header.type = DMUB_CMD__PR;
+	cmd.pr_general_cmd.header.sub_type = DMUB_CMD__PR_GENERAL_CMD;
+	cmd.pr_general_cmd.header.payload_bytes = sizeof(struct dmub_cmd_pr_general_cmd_data);
+	cmd.pr_general_cmd.data.panel_inst = (uint8_t)panel_inst;
+
+	dc_wake_and_execute_dmub_cmd(dc->ctx, &cmd, DM_DMUB_WAIT_TYPE_WAIT);
+	return true;
+}
+
+bool dp_pr_get_state(const struct dc_link *link, uint64_t *state)
+{
+	const struct dc *dc = link->ctx->dc;
+	unsigned int panel_inst = 0;
+	uint32_t retry_count = 0;
+	uint32_t replay_state = PR_STATE_INVALID;
+
+	if (!dp_pr_get_panel_inst(dc, link, &panel_inst))
+		return false;
+
+	do {
+		// Send gpint command and wait for ack
+		if (!dc_wake_and_execute_gpint(dc->ctx, DMUB_GPINT__GET_REPLAY_STATE, (uint16_t)panel_inst,
+					       &replay_state, DM_DMUB_WAIT_TYPE_WAIT_WITH_REPLY)) {
+			// Return invalid state when GPINT times out
+			replay_state = PR_STATE_INVALID;
+		}
+		/* Copy 32-bit result into 64-bit output */
+		*state = replay_state;
+	} while (++retry_count <= 1000 && *state == PR_STATE_INVALID);
+
+	// Assert if max retry hit
+	if (retry_count >= 1000 && *state == PR_STATE_INVALID) {
+		ASSERT(0);
+		/* To-do: Add retry fail log */
+	}
+
+	return true;
+}

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_panel_replay.h

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2025 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+#ifndef __DC_LINK_DP_PANEL_REPLAY_H__
+#define __DC_LINK_DP_PANEL_REPLAY_H__
+
+#include "link_service.h"
+
+bool dp_setup_replay(struct dc_link *link, const struct dc_stream_state *stream);
+bool dp_pr_get_panel_inst(const struct dc *dc, const struct dc_link *link, unsigned int *inst_out);
+bool dp_pr_enable(struct dc_link *link, bool enable);
+bool dp_pr_copy_settings(struct dc_link *link, struct replay_context *replay_context);
+bool dp_pr_update_state(struct dc_link *link, struct dmub_cmd_pr_update_state_data *update_state_data);
+bool dp_pr_set_general_cmd(struct dc_link *link, struct dmub_cmd_pr_general_cmd_data *general_cmd_data);
+bool dp_pr_get_state(const struct dc_link *link, uint64_t *state);
+
+#endif /* __DC_LINK_DP_PANEL_REPLAY_H__ */

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.c

@@ -0,0 +1,210 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+/* FILE POLICY AND INTENDED USAGE:
+ * This file implements basic dp phy functionality such as enable/disable phy
+ * output and set lane/drive settings. This file is responsible for maintaining
+ * and update software state representing current phy status such as current
+ * link settings.
+ */
+
+#include "link_dp_phy.h"
+#include "link_dpcd.h"
+#include "link_dp_training.h"
+#include "link_dp_capability.h"
+#include "clk_mgr.h"
+#include "resource.h"
+#include "link_enc_cfg.h"
+#include "atomfirmware.h"
+#define DC_LOGGER \
+	link->ctx->logger
+
+void dpcd_write_rx_power_ctrl(struct dc_link *link, bool on)
+{
+	uint8_t state;
+
+	state = on ? DP_POWER_STATE_D0 : DP_POWER_STATE_D3;
+
+	if (link->sync_lt_in_progress)
+		return;
+
+	core_link_write_dpcd(link, DP_SET_POWER, &state,
+						 sizeof(state));
+
+}
+
+void dp_enable_link_phy(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	enum signal_type signal,
+	enum clock_source_id clock_source,
+	const struct dc_link_settings *link_settings)
+{
+	link->cur_link_settings = *link_settings;
+	link->dc->hwss.enable_dp_link_output(link, link_res, signal,
+			clock_source, link_settings);
+	dpcd_write_rx_power_ctrl(link, true);
+}
+
+void dp_disable_link_phy(struct dc_link *link,
+		const struct link_resource *link_res,
+		enum signal_type signal)
+{
+	struct dc  *dc = link->ctx->dc;
+
+	if (!link->wa_flags.dp_keep_receiver_powered &&
+			!link->skip_implict_edp_power_control &&
+			link->type != dc_connection_none)
+		dpcd_write_rx_power_ctrl(link, false);
+
+	dc->hwss.disable_link_output(link, link_res, signal);
+	/* Clear current link setting.*/
+	memset(&link->cur_link_settings, 0,
+			sizeof(link->cur_link_settings));
+
+	if (dc->clk_mgr->funcs->notify_link_rate_change)
+		dc->clk_mgr->funcs->notify_link_rate_change(dc->clk_mgr, link);
+}
+
+static inline bool is_immediate_downstream(struct dc_link *link, uint32_t offset)
+{
+	return (dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt) ==
+			offset);
+}
+
+void dp_set_hw_lane_settings(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	const struct link_training_settings *link_settings,
+	uint32_t offset)
+{
+	const struct link_hwss *link_hwss = get_link_hwss(link, link_res);
+
+	// Don't return here if using FIXED_VS link HWSS and encoding is 128b/132b
+	if ((link_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) &&
+			!is_immediate_downstream(link, offset) &&
+			(!((link->chip_caps & AMD_EXT_DISPLAY_PATH_CAPS__EXT_CHIP_MASK) == AMD_EXT_DISPLAY_PATH_CAPS__DP_FIXED_VS_EN) ||
+			link_dp_get_encoding_format(&link_settings->link_settings) == DP_8b_10b_ENCODING))
+		return;
+
+	if (link_hwss->ext.set_dp_lane_settings)
+		link_hwss->ext.set_dp_lane_settings(link, link_res,
+				&link_settings->link_settings,
+				link_settings->hw_lane_settings);
+
+	memmove(link->cur_lane_setting,
+			link_settings->hw_lane_settings,
+			sizeof(link->cur_lane_setting));
+}
+
+void dp_set_drive_settings(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	struct link_training_settings *lt_settings)
+{
+	/* program ASIC PHY settings*/
+	dp_set_hw_lane_settings(link, link_res, lt_settings, DPRX);
+
+	dp_hw_to_dpcd_lane_settings(lt_settings,
+			lt_settings->hw_lane_settings,
+			lt_settings->dpcd_lane_settings);
+
+	/* Notify DP sink the PHY settings from source */
+	dpcd_set_lane_settings(link, lt_settings, DPRX);
+}
+
+enum dc_status dp_set_fec_ready(struct dc_link *link, const struct link_resource *link_res, bool ready)
+{
+	/* FEC has to be "set ready" before the link training.
+	 * The policy is to always train with FEC
+	 * if the sink supports it and leave it enabled on link.
+	 * If FEC is not supported, disable it.
+	 */
+	struct link_encoder *link_enc = link_res->dio_link_enc;
+	enum dc_status status = DC_OK;
+	uint8_t fec_config = 0;
+
+	if (!link->dc->config.unify_link_enc_assignment)
+		link_enc = link_enc_cfg_get_link_enc(link);
+	ASSERT(link_enc);
+	if (link_enc->funcs->fec_set_ready == NULL)
+		return DC_NOT_SUPPORTED;
+
+	if (ready && dp_should_enable_fec(link)) {
+		fec_config = 1;
+
+		status = core_link_write_dpcd(link, DP_FEC_CONFIGURATION,
+				&fec_config, sizeof(fec_config));
+
+		if (status == DC_OK) {
+			link_enc->funcs->fec_set_ready(link_enc, true);
+			link->fec_state = dc_link_fec_ready;
+		}
+	} else {
+		if (link->fec_state == dc_link_fec_ready) {
+			fec_config = 0;
+			if (link->type != dc_connection_none)
+				core_link_write_dpcd(link, DP_FEC_CONFIGURATION,
+					&fec_config, sizeof(fec_config));
+
+			link_enc->funcs->fec_set_ready(link_enc, false);
+			link->fec_state = dc_link_fec_not_ready;
+		}
+	}
+
+	return status;
+}
+
+void dp_set_fec_enable(struct dc_link *link, const struct link_resource *link_res, bool enable)
+{
+	struct link_encoder *link_enc = link_res->dio_link_enc;
+
+	if (!link->dc->config.unify_link_enc_assignment)
+		link_enc = link_enc_cfg_get_link_enc(link);
+
+	if (link_enc == NULL || link_enc->funcs == NULL || link_enc->funcs->fec_set_enable == NULL)
+		return;
+
+	if (enable && dp_should_enable_fec(link)) {
+		if (link->fec_state == dc_link_fec_ready) {
+			/* According to DP spec, FEC enable sequence can first
+			 * be transmitted anytime after 1000 LL codes have
+			 * been transmitted on the link after link training
+			 * completion. Using 1 lane RBR should have the maximum
+			 * time for transmitting 1000 LL codes which is 6.173 us.
+			 * So use 7 microseconds delay instead.
+			 */
+			udelay(7);
+			link_enc->funcs->fec_set_enable(link_enc, true);
+			link->fec_state = dc_link_fec_enabled;
+		}
+	} else {
+		if (link->fec_state == dc_link_fec_enabled) {
+			link_enc->funcs->fec_set_enable(link_enc, false);
+			link->fec_state = dc_link_fec_ready;
+		}
+	}
+}
+

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_phy.h

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#ifndef __DC_LINK_DP_PHY_H__
+#define __DC_LINK_DP_PHY_H__
+
+#include "link_service.h"
+void dp_enable_link_phy(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	enum signal_type signal,
+	enum clock_source_id clock_source,
+	const struct dc_link_settings *link_settings);
+
+void dp_disable_link_phy(struct dc_link *link,
+		const struct link_resource *link_res,
+		enum signal_type signal);
+
+void dp_set_hw_lane_settings(
+		struct dc_link *link,
+		const struct link_resource *link_res,
+		const struct link_training_settings *link_settings,
+		uint32_t offset);
+
+void dp_set_drive_settings(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	struct link_training_settings *lt_settings);
+
+enum dc_status dp_set_fec_ready(struct dc_link *link,
+		const struct link_resource *link_res, bool ready);
+
+void dp_set_fec_enable(struct dc_link *link,
+		const struct link_resource *link_res, bool enable);
+
+void dpcd_write_rx_power_ctrl(struct dc_link *link, bool on);
+
+#endif /* __DC_LINK_DP_PHY_H__ */

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training.h

@@ -0,0 +1,201 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+
+#ifndef __DC_LINK_DP_TRAINING_H__
+#define __DC_LINK_DP_TRAINING_H__
+#include "link_service.h"
+
+bool perform_link_training_with_retries(
+	const struct dc_link_settings *link_setting,
+	bool skip_video_pattern,
+	int attempts,
+	struct pipe_ctx *pipe_ctx,
+	enum signal_type signal,
+	bool do_fallback);
+
+enum link_training_result dp_perform_link_training(
+		struct dc_link *link,
+		const struct link_resource *link_res,
+		const struct dc_link_settings *link_settings,
+		bool skip_video_pattern);
+
+bool dp_set_hw_training_pattern(
+		struct dc_link *link,
+		const struct link_resource *link_res,
+		enum dc_dp_training_pattern pattern,
+		uint32_t offset);
+
+void dp_set_hw_test_pattern(
+		struct dc_link *link,
+		const struct link_resource *link_res,
+		enum dp_test_pattern test_pattern,
+		uint8_t *custom_pattern,
+		uint32_t custom_pattern_size);
+
+enum dc_status dpcd_set_training_pattern(
+	struct dc_link *link,
+	enum dc_dp_training_pattern training_pattern);
+
+/* Write DPCD drive settings. */
+enum dc_status dpcd_set_lane_settings(
+	struct dc_link *link,
+	const struct link_training_settings *link_training_setting,
+	uint32_t offset);
+
+/* Write DPCD link configuration data. */
+enum dc_status dpcd_set_link_settings(
+	struct dc_link *link,
+	const struct link_training_settings *lt_settings);
+
+void dpcd_set_lt_pattern_and_lane_settings(
+	struct dc_link *link,
+	const struct link_training_settings *lt_settings,
+	enum dc_dp_training_pattern pattern,
+	uint32_t offset);
+
+/* Read training status and adjustment requests from DPCD. */
+enum dc_status dp_get_lane_status_and_lane_adjust(
+	struct dc_link *link,
+	const struct link_training_settings *link_training_setting,
+	union lane_status ln_status[LANE_COUNT_DP_MAX],
+	union lane_align_status_updated *ln_align,
+	union lane_adjust ln_adjust[LANE_COUNT_DP_MAX],
+	uint32_t offset);
+
+enum dc_status dpcd_configure_lttpr_mode(
+		struct dc_link *link,
+		struct link_training_settings *lt_settings);
+
+enum dc_status configure_lttpr_mode_transparent(struct dc_link *link);
+
+enum dc_status dpcd_configure_channel_coding(
+		struct dc_link *link,
+		struct link_training_settings *lt_settings);
+
+void repeater_training_done(struct dc_link *link, uint32_t offset);
+
+void start_clock_recovery_pattern_early(struct dc_link *link,
+		const struct link_resource *link_res,
+		struct link_training_settings *lt_settings,
+		uint32_t offset);
+
+void dp_decide_training_settings(
+		struct dc_link *link,
+		const struct link_resource *link_res,
+		const struct dc_link_settings *link_settings,
+		struct link_training_settings *lt_settings);
+
+void dp_decide_lane_settings(
+	const struct link_training_settings *lt_settings,
+	const union lane_adjust ln_adjust[LANE_COUNT_DP_MAX],
+	struct dc_lane_settings hw_lane_settings[LANE_COUNT_DP_MAX],
+	union dpcd_training_lane *dpcd_lane_settings);
+
+enum dc_dp_training_pattern decide_cr_training_pattern(
+		const struct dc_link_settings *link_settings);
+
+enum dc_dp_training_pattern decide_eq_training_pattern(struct dc_link *link,
+		const struct link_resource *link_res,
+		const struct dc_link_settings *link_settings);
+
+enum lttpr_mode dp_decide_lttpr_mode(struct dc_link *link,
+		struct dc_link_settings *link_setting);
+
+void dp_get_lttpr_mode_override(struct dc_link *link,
+		enum lttpr_mode *override);
+
+void override_training_settings(
+		struct dc_link *link,
+		const struct dc_link_training_overrides *overrides,
+		struct link_training_settings *lt_settings);
+
+/* Check DPCD training status registers to detect link loss. */
+enum link_training_result dp_check_link_loss_status(
+		struct dc_link *link,
+		const struct link_training_settings *link_training_setting);
+
+bool dp_is_cr_done(enum dc_lane_count ln_count,
+	union lane_status *dpcd_lane_status);
+
+bool dp_is_ch_eq_done(enum dc_lane_count ln_count,
+	union lane_status *dpcd_lane_status);
+bool dp_is_symbol_locked(enum dc_lane_count ln_count,
+	union lane_status *dpcd_lane_status);
+bool dp_is_interlane_aligned(union lane_align_status_updated align_status);
+
+bool is_repeater(const struct link_training_settings *lt_settings, uint32_t offset);
+
+bool dp_is_max_vs_reached(
+	const struct link_training_settings *lt_settings);
+
+uint8_t get_dpcd_link_rate(const struct dc_link_settings *link_settings);
+
+enum link_training_result dp_get_cr_failure(enum dc_lane_count ln_count,
+	union lane_status *dpcd_lane_status);
+
+void dp_hw_to_dpcd_lane_settings(
+	const struct link_training_settings *lt_settings,
+	const struct dc_lane_settings hw_lane_settings[LANE_COUNT_DP_MAX],
+	union dpcd_training_lane dpcd_lane_settings[LANE_COUNT_DP_MAX]);
+
+void dp_wait_for_training_aux_rd_interval(
+	struct dc_link *link,
+	uint32_t wait_in_micro_secs);
+
+enum dpcd_training_patterns
+	dp_training_pattern_to_dpcd_training_pattern(
+	struct dc_link *link,
+	enum dc_dp_training_pattern pattern);
+
+uint8_t dp_initialize_scrambling_data_symbols(
+	struct dc_link *link,
+	enum dc_dp_training_pattern pattern);
+
+void dp_log_training_result(
+	struct dc_link *link,
+	const struct link_training_settings *lt_settings,
+	enum link_training_result status);
+
+uint32_t dp_translate_training_aux_read_interval(
+		uint32_t dpcd_aux_read_interval);
+
+uint8_t dp_get_nibble_at_index(const uint8_t *buf,
+	uint32_t index);
+
+bool dp_check_interlane_aligned(union lane_align_status_updated align_status,
+		struct dc_link *link,
+		uint8_t retries);
+
+uint32_t dp_get_eq_aux_rd_interval(
+		const struct dc_link *link,
+		const struct link_training_settings *lt_settings,
+		uint32_t offset,
+		uint8_t retries);
+
+bool dp_check_dpcd_reqeust_status(const struct dc_link *link,
+		enum dc_status status);
+
+#endif /* __DC_LINK_DP_TRAINING_H__ */

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_128b_132b.c

@@ -0,0 +1,268 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+/* FILE POLICY AND INTENDED USAGE:
+ * This file implements dp 128b/132b link training software policies and
+ * sequences.
+ */
+#include "link_dp_training_128b_132b.h"
+#include "link_dp_training_8b_10b.h"
+#include "link_dpcd.h"
+#include "link_dp_phy.h"
+#include "link_dp_capability.h"
+
+#define DC_LOGGER \
+	link->ctx->logger
+
+static enum dc_status dpcd_128b_132b_set_lane_settings(
+		struct dc_link *link,
+		const struct link_training_settings *link_training_setting)
+{
+	enum dc_status status = core_link_write_dpcd(link,
+			DP_TRAINING_LANE0_SET,
+			(uint8_t *)(link_training_setting->dpcd_lane_settings),
+			sizeof(link_training_setting->dpcd_lane_settings));
+
+	DC_LOG_HW_LINK_TRAINING("%s:\n 0x%X TX_FFE_PRESET_VALUE = %x\n",
+			__func__,
+			DP_TRAINING_LANE0_SET,
+			link_training_setting->dpcd_lane_settings[0].tx_ffe.PRESET_VALUE);
+	return status;
+}
+
+static void dpcd_128b_132b_get_aux_rd_interval(struct dc_link *link,
+		uint32_t *interval_in_us)
+{
+	union dp_128b_132b_training_aux_rd_interval dpcd_interval;
+	uint32_t interval_unit = 0;
+
+	dpcd_interval.raw = 0;
+	core_link_read_dpcd(link, DP_128B132B_TRAINING_AUX_RD_INTERVAL,
+			&dpcd_interval.raw, sizeof(dpcd_interval.raw));
+	interval_unit = dpcd_interval.bits.UNIT ? 1 : 2; /* 0b = 2 ms, 1b = 1 ms */
+	/* (128b/132b_TRAINING_AUX_RD_INTERVAL value + 1) *
+	 * INTERVAL_UNIT. The maximum is 256 ms
+	 */
+	*interval_in_us = (dpcd_interval.bits.VALUE + 1) * interval_unit * 1000;
+}
+
+static enum link_training_result dp_perform_128b_132b_channel_eq_done_sequence(
+		struct dc_link *link,
+		const struct link_resource *link_res,
+		struct link_training_settings *lt_settings)
+{
+	uint8_t loop_count;
+	uint32_t aux_rd_interval = 0;
+	uint32_t wait_time = 0;
+	union lane_align_status_updated dpcd_lane_status_updated = {0};
+	union lane_status dpcd_lane_status[LANE_COUNT_DP_MAX] = {0};
+	union lane_adjust dpcd_lane_adjust[LANE_COUNT_DP_MAX] = {0};
+	enum dc_status status = DC_OK;
+	enum link_training_result result = LINK_TRAINING_SUCCESS;
+
+	/* Transmit 128b/132b_TPS1 over Main-Link */
+	dp_set_hw_training_pattern(link, link_res, lt_settings->pattern_for_cr, DPRX);
+
+	/* Set TRAINING_PATTERN_SET to 01h */
+	dpcd_set_training_pattern(link, lt_settings->pattern_for_cr);
+
+	/* Adjust TX_FFE_PRESET_VALUE and Transmit 128b/132b_TPS2 over Main-Link */
+	dpcd_128b_132b_get_aux_rd_interval(link, &aux_rd_interval);
+	dp_get_lane_status_and_lane_adjust(link, lt_settings, dpcd_lane_status,
+			&dpcd_lane_status_updated, dpcd_lane_adjust, DPRX);
+	dp_decide_lane_settings(lt_settings, dpcd_lane_adjust,
+			lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings);
+	dp_set_hw_lane_settings(link, link_res, lt_settings, DPRX);
+	dp_set_hw_training_pattern(link, link_res, lt_settings->pattern_for_eq, DPRX);
+
+	/* Set loop counter to start from 1 */
+	loop_count = 1;
+
+	/* Set TRAINING_PATTERN_SET to 02h and TX_FFE_PRESET_VALUE in one AUX transaction */
+	dpcd_set_lt_pattern_and_lane_settings(link, lt_settings,
+			lt_settings->pattern_for_eq, DPRX);
+
+	/* poll for channel EQ done */
+	while (result == LINK_TRAINING_SUCCESS) {
+		dp_wait_for_training_aux_rd_interval(link, aux_rd_interval);
+		wait_time += aux_rd_interval;
+		status = dp_get_lane_status_and_lane_adjust(link, lt_settings, dpcd_lane_status,
+				&dpcd_lane_status_updated, dpcd_lane_adjust, DPRX);
+		dp_decide_lane_settings(lt_settings, dpcd_lane_adjust,
+				lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings);
+		dpcd_128b_132b_get_aux_rd_interval(link, &aux_rd_interval);
+		if (status != DC_OK) {
+			result = LINK_TRAINING_ABORT;
+		} else if (dp_is_ch_eq_done(lt_settings->link_settings.lane_count,
+				dpcd_lane_status)) {
+			/* pass */
+			break;
+		} else if (loop_count >= lt_settings->eq_loop_count_limit) {
+			result = DP_128b_132b_MAX_LOOP_COUNT_REACHED;
+		} else if (dpcd_lane_status_updated.bits.LT_FAILED_128b_132b) {
+			result = DP_128b_132b_LT_FAILED;
+		} else {
+			dp_set_hw_lane_settings(link, link_res, lt_settings, DPRX);
+			dpcd_128b_132b_set_lane_settings(link, lt_settings);
+		}
+		loop_count++;
+	}
+
+	/* poll for EQ interlane align done */
+	while (result == LINK_TRAINING_SUCCESS) {
+		if (status != DC_OK) {
+			result = LINK_TRAINING_ABORT;
+		} else if (dpcd_lane_status_updated.bits.EQ_INTERLANE_ALIGN_DONE_128b_132b) {
+			/* pass */
+			break;
+		} else if (wait_time >= lt_settings->eq_wait_time_limit) {
+			result = DP_128b_132b_CHANNEL_EQ_DONE_TIMEOUT;
+		} else if (dpcd_lane_status_updated.bits.LT_FAILED_128b_132b) {
+			result = DP_128b_132b_LT_FAILED;
+		} else {
+			dp_wait_for_training_aux_rd_interval(link,
+					lt_settings->eq_pattern_time);
+			wait_time += lt_settings->eq_pattern_time;
+			status = dp_get_lane_status_and_lane_adjust(link, lt_settings, dpcd_lane_status,
+					&dpcd_lane_status_updated, dpcd_lane_adjust, DPRX);
+		}
+	}
+
+	return result;
+}
+
+static enum link_training_result dp_perform_128b_132b_cds_done_sequence(
+		struct dc_link *link,
+		const struct link_resource *link_res,
+		struct link_training_settings *lt_settings)
+{
+	(void)link_res;
+	/* Assumption: assume hardware has transmitted eq pattern */
+	enum dc_status status = DC_OK;
+	enum link_training_result result = LINK_TRAINING_SUCCESS;
+	union lane_align_status_updated dpcd_lane_status_updated = {0};
+	union lane_status dpcd_lane_status[LANE_COUNT_DP_MAX] = {0};
+	union lane_adjust dpcd_lane_adjust[LANE_COUNT_DP_MAX] = {0};
+	uint32_t wait_time = 0;
+
+	/* initiate CDS done sequence */
+	dpcd_set_training_pattern(link, lt_settings->pattern_for_cds);
+
+	/* poll for CDS interlane align done and symbol lock */
+	while (result == LINK_TRAINING_SUCCESS) {
+		dp_wait_for_training_aux_rd_interval(link,
+				lt_settings->cds_pattern_time);
+		wait_time += lt_settings->cds_pattern_time;
+		status = dp_get_lane_status_and_lane_adjust(link, lt_settings, dpcd_lane_status,
+						&dpcd_lane_status_updated, dpcd_lane_adjust, DPRX);
+		if (status != DC_OK) {
+			result = LINK_TRAINING_ABORT;
+		} else if (dp_is_symbol_locked(lt_settings->link_settings.lane_count, dpcd_lane_status) &&
+				dpcd_lane_status_updated.bits.CDS_INTERLANE_ALIGN_DONE_128b_132b) {
+			/* pass */
+			break;
+		} else if (dpcd_lane_status_updated.bits.LT_FAILED_128b_132b) {
+			result = DP_128b_132b_LT_FAILED;
+		} else if (wait_time >= lt_settings->cds_wait_time_limit) {
+			result = DP_128b_132b_CDS_DONE_TIMEOUT;
+		}
+	}
+
+	return result;
+}
+
+enum link_training_result dp_perform_128b_132b_link_training(
+		struct dc_link *link,
+		const struct link_resource *link_res,
+		struct link_training_settings *lt_settings)
+{
+	enum link_training_result result = LINK_TRAINING_SUCCESS;
+
+	/* TODO - DP2.0 Link: remove legacy_dp2_lt logic */
+	if (link->dc->debug.legacy_dp2_lt) {
+		struct link_training_settings legacy_settings;
+
+		decide_8b_10b_training_settings(link,
+				link_res,
+				&lt_settings->link_settings,
+				&legacy_settings);
+		return dp_perform_8b_10b_link_training(link, link_res, &legacy_settings);
+	}
+
+	dpcd_set_link_settings(link, lt_settings);
+
+	if (result == LINK_TRAINING_SUCCESS) {
+		result = dp_perform_128b_132b_channel_eq_done_sequence(link, link_res, lt_settings);
+		if (result == LINK_TRAINING_SUCCESS)
+			DC_LOG_HW_LINK_TRAINING("%s: Channel EQ done.\n", __func__);
+	}
+
+	if (result == LINK_TRAINING_SUCCESS) {
+		result = dp_perform_128b_132b_cds_done_sequence(link, link_res, lt_settings);
+		if (result == LINK_TRAINING_SUCCESS)
+			DC_LOG_HW_LINK_TRAINING("%s: CDS done.\n", __func__);
+	}
+
+	return result;
+}
+
+void decide_128b_132b_training_settings(struct dc_link *link,
+		const struct link_resource *link_res,
+		const struct dc_link_settings *link_settings,
+		struct link_training_settings *lt_settings)
+{
+	memset(lt_settings, 0, sizeof(*lt_settings));
+
+	lt_settings->link_settings = *link_settings;
+	/* TODO: should decide link spread when populating link_settings */
+	lt_settings->link_settings.link_spread = link->dp_ss_off ? LINK_SPREAD_DISABLED :
+			LINK_SPREAD_05_DOWNSPREAD_30KHZ;
+
+	lt_settings->pattern_for_cr = decide_cr_training_pattern(link_settings);
+	lt_settings->pattern_for_eq = decide_eq_training_pattern(link, link_res, link_settings);
+	lt_settings->eq_pattern_time = 2500;
+	lt_settings->eq_wait_time_limit = 400000;
+	lt_settings->eq_loop_count_limit = 20;
+	lt_settings->pattern_for_cds = DP_128b_132b_TPS2_CDS;
+	lt_settings->cds_pattern_time = 2500;
+	lt_settings->cds_wait_time_limit = (dp_parse_lttpr_repeater_count(
+			link->dpcd_caps.lttpr_caps.phy_repeater_cnt) + 1) * 20000;
+	lt_settings->disallow_per_lane_settings = true;
+	lt_settings->lttpr_mode = dp_decide_128b_132b_lttpr_mode(link);
+	dp_hw_to_dpcd_lane_settings(lt_settings,
+			lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings);
+}
+
+enum lttpr_mode dp_decide_128b_132b_lttpr_mode(struct dc_link *link)
+{
+	enum lttpr_mode mode = LTTPR_MODE_NON_LTTPR;
+
+	if (dp_is_lttpr_present(link))
+		mode = LTTPR_MODE_NON_TRANSPARENT;
+
+	DC_LOG_DC("128b_132b chose LTTPR_MODE %d.\n", mode);
+	return mode;
+}
+

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_128b_132b.h

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+
+#ifndef __DC_LINK_DP_TRAINING_128B_132B_H__
+#define __DC_LINK_DP_TRAINING_128B_132B_H__
+#include "link_dp_training.h"
+
+enum link_training_result dp_perform_128b_132b_link_training(
+		struct dc_link *link,
+		const struct link_resource *link_res,
+		struct link_training_settings *lt_settings);
+
+void decide_128b_132b_training_settings(struct dc_link *link,
+		const struct link_resource *link_res,
+		const struct dc_link_settings *link_settings,
+		struct link_training_settings *lt_settings);
+
+enum lttpr_mode dp_decide_128b_132b_lttpr_mode(struct dc_link *link);
+
+#endif /* __DC_LINK_DP_TRAINING_128B_132B_H__ */

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_8b_10b.c

@@ -0,0 +1,491 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+/* FILE POLICY AND INTENDED USAGE:
+ * This file implements dp 8b/10b link training software policies and
+ * sequences.
+ */
+#include "link_dp_training_8b_10b.h"
+#include "link_dpcd.h"
+#include "link_dp_phy.h"
+#include "link_dp_capability.h"
+
+#define DC_LOGGER \
+	link->ctx->logger
+
+static void get_default_8b_10b_lttpr_aux_rd_interval(
+		union training_aux_rd_interval *training_rd_interval)
+{
+	/* LTTPR are required to program DPCD 0000Eh to 0x4 (16ms) upon AUX
+	 * read reply to this register. Since old sinks with DPCD rev 1.1
+	 * and earlier may not support this register, assume the mandatory
+	 * value is programmed by the LTTPR to avoid AUX timeout issues.
+	 */
+	training_rd_interval->raw = 0x4;
+}
+
+static int32_t get_cr_training_aux_rd_interval(struct dc_link *link,
+		const struct dc_link_settings *link_settings,
+		enum lttpr_mode lttpr_mode)
+{
+	union training_aux_rd_interval training_rd_interval;
+	uint32_t wait_in_micro_secs = 100;
+
+	memset(&training_rd_interval, 0, sizeof(training_rd_interval));
+	if (link_dp_get_encoding_format(link_settings) == DP_8b_10b_ENCODING) {
+		if (link->dpcd_caps.dpcd_rev.raw >= DPCD_REV_12)
+			core_link_read_dpcd(
+					link,
+					DP_TRAINING_AUX_RD_INTERVAL,
+					(uint8_t *)&training_rd_interval,
+					sizeof(training_rd_interval));
+		else if (dp_is_lttpr_present(link))
+			get_default_8b_10b_lttpr_aux_rd_interval(&training_rd_interval);
+
+		if (training_rd_interval.raw != 0) {
+			if (lttpr_mode != LTTPR_MODE_NON_TRANSPARENT)
+				wait_in_micro_secs = 400;
+			if (training_rd_interval.bits.TRAINIG_AUX_RD_INTERVAL)
+				wait_in_micro_secs = training_rd_interval.bits.TRAINIG_AUX_RD_INTERVAL * 4000;
+		}
+	}
+	return wait_in_micro_secs;
+}
+
+static uint32_t get_eq_training_aux_rd_interval(
+	struct dc_link *link,
+	const struct dc_link_settings *link_settings)
+{
+	union training_aux_rd_interval training_rd_interval;
+
+	memset(&training_rd_interval, 0, sizeof(training_rd_interval));
+	if (link_dp_get_encoding_format(link_settings) == DP_128b_132b_ENCODING) {
+		core_link_read_dpcd(
+				link,
+				DP_128B132B_TRAINING_AUX_RD_INTERVAL,
+				(uint8_t *)&training_rd_interval,
+				sizeof(training_rd_interval));
+	} else if (link_dp_get_encoding_format(link_settings) == DP_8b_10b_ENCODING) {
+		if (link->dpcd_caps.dpcd_rev.raw >= DPCD_REV_12)
+			core_link_read_dpcd(
+					link,
+					DP_TRAINING_AUX_RD_INTERVAL,
+					(uint8_t *)&training_rd_interval,
+					sizeof(training_rd_interval));
+		else if (dp_is_lttpr_present(link))
+			get_default_8b_10b_lttpr_aux_rd_interval(&training_rd_interval);
+	}
+
+	switch (training_rd_interval.bits.TRAINIG_AUX_RD_INTERVAL) {
+	case 0: return 400;
+	case 1: return 4000;
+	case 2: return 8000;
+	case 3: return 12000;
+	case 4: return 16000;
+	case 5: return 32000;
+	case 6: return 64000;
+	default: return 400;
+	}
+}
+
+void decide_8b_10b_training_settings(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	const struct dc_link_settings *link_setting,
+	struct link_training_settings *lt_settings)
+{
+	memset(lt_settings, '\0', sizeof(struct link_training_settings));
+
+	/* Initialize link settings */
+	lt_settings->link_settings.use_link_rate_set = link_setting->use_link_rate_set;
+	lt_settings->link_settings.link_rate_set = link_setting->link_rate_set;
+	lt_settings->link_settings.link_rate = link_setting->link_rate;
+	lt_settings->link_settings.lane_count = link_setting->lane_count;
+	/* TODO hard coded to SS for now
+	 * lt_settings.link_settings.link_spread =
+	 * dal_display_path_is_ss_supported(
+	 * path_mode->display_path) ?
+	 * LINK_SPREAD_05_DOWNSPREAD_30KHZ :
+	 * LINK_SPREAD_DISABLED;
+	 */
+	lt_settings->link_settings.link_spread = link->dp_ss_off ?
+			LINK_SPREAD_DISABLED : LINK_SPREAD_05_DOWNSPREAD_30KHZ;
+	lt_settings->eq_pattern_time = (uint16_t)get_eq_training_aux_rd_interval(link, link_setting);
+	lt_settings->pattern_for_cr = decide_cr_training_pattern(link_setting);
+	lt_settings->pattern_for_eq = decide_eq_training_pattern(link, link_res, link_setting);
+	lt_settings->enhanced_framing = 1;
+	lt_settings->should_set_fec_ready = true;
+	lt_settings->disallow_per_lane_settings = true;
+	lt_settings->always_match_dpcd_with_hw_lane_settings = true;
+	lt_settings->lttpr_mode = dp_decide_8b_10b_lttpr_mode(link);
+	lt_settings->cr_pattern_time = (uint16_t)get_cr_training_aux_rd_interval(link, link_setting, lt_settings->lttpr_mode);
+	dp_hw_to_dpcd_lane_settings(lt_settings, lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings);
+
+	/* Some embedded LTTPRs rely on receiving TPS2 before LT to interop reliably with sensitive VGA dongles
+	 * This allows these LTTPRs to minimize freq/phase and skew variation during lock and deskew sequences
+	 */
+	if ((link->chip_caps & AMD_EXT_DISPLAY_PATH_CAPS__EXT_CHIP_MASK) ==
+			AMD_EXT_DISPLAY_PATH_CAPS__DP_EARLY_8B10B_TPS2) {
+		lt_settings->lttpr_early_tps2 = true;
+	}
+}
+
+enum lttpr_mode dp_decide_8b_10b_lttpr_mode(struct dc_link *link)
+{
+	bool is_lttpr_present = dp_is_lttpr_present(link);
+	bool vbios_lttpr_force_non_transparent = link->dc->caps.vbios_lttpr_enable;
+	bool vbios_lttpr_aware = link->dc->caps.vbios_lttpr_aware;
+
+	if (!is_lttpr_present)
+		return LTTPR_MODE_NON_LTTPR;
+
+	if (vbios_lttpr_aware) {
+		if (vbios_lttpr_force_non_transparent) {
+			DC_LOG_DC("chose LTTPR_MODE_NON_TRANSPARENT due to VBIOS DCE_INFO_CAPS_LTTPR_SUPPORT_ENABLE set to 1.\n");
+			return LTTPR_MODE_NON_TRANSPARENT;
+		} else {
+			DC_LOG_DC("chose LTTPR_MODE_NON_TRANSPARENT by default due to VBIOS not set DCE_INFO_CAPS_LTTPR_SUPPORT_ENABLE set to 1.\n");
+			return LTTPR_MODE_TRANSPARENT;
+		}
+	}
+
+	if (link->dc->config.allow_lttpr_non_transparent_mode.bits.DP1_4A &&
+			link->dc->caps.extended_aux_timeout_support) {
+		DC_LOG_DC("chose LTTPR_MODE_NON_TRANSPARENT by default and dc->config.allow_lttpr_non_transparent_mode.bits.DP1_4A set to 1.\n");
+		return LTTPR_MODE_NON_TRANSPARENT;
+	}
+
+	DC_LOG_DC("chose LTTPR_MODE_NON_LTTPR.\n");
+	return LTTPR_MODE_NON_LTTPR;
+}
+
+static void set_link_settings_and_perform_early_tps2_retimer_pre_lt_sequence(struct dc_link *link,
+	const struct link_resource *link_res,
+	struct link_training_settings *lt_settings,
+	uint32_t lttpr_count)
+{
+	/* Vendor-specific LTTPR early TPS2 sequence:
+	* 1. Output TPS2
+	* 2. Wait 400us
+	* 3. Set link settings as usual
+	* 4. Write TPS1 to DP_TRAINING_PATTERN_SET_PHY_REPEATERx targeting LTTPR closest to host
+	* 5. Wait 1ms
+	* 6. Begin link training as usual
+	* */
+
+	uint32_t closest_lttpr_address_offset = dp_get_closest_lttpr_offset((uint8_t)lttpr_count);
+
+	union dpcd_training_pattern dpcd_pattern = {0};
+
+	dpcd_pattern.v1_4.TRAINING_PATTERN_SET = 1;
+	dpcd_pattern.v1_4.SCRAMBLING_DISABLE = 1;
+
+	DC_LOG_HW_LINK_TRAINING("%s\n GPU sends TPS2. Wait 400us.\n", __func__);
+
+	dp_set_hw_training_pattern(link, link_res, DP_TRAINING_PATTERN_SEQUENCE_2, DPRX);
+
+	dp_set_hw_lane_settings(link, link_res, lt_settings, DPRX);
+
+	udelay(400);
+
+	dpcd_set_link_settings(link, lt_settings);
+
+	core_link_write_dpcd(link, DP_TRAINING_PATTERN_SET_PHY_REPEATER1 + closest_lttpr_address_offset, &dpcd_pattern.raw, 1);
+
+	udelay(1000);
+	}
+
+enum link_training_result perform_8b_10b_clock_recovery_sequence(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	struct link_training_settings *lt_settings,
+	uint32_t offset)
+{
+	enum dc_status status;
+	uint32_t retries_cr;
+	uint32_t retry_count;
+	uint32_t wait_time_microsec;
+	enum dc_lane_count lane_count = lt_settings->link_settings.lane_count;
+	union lane_status dpcd_lane_status[LANE_COUNT_DP_MAX];
+	union lane_align_status_updated dpcd_lane_status_updated;
+	union lane_adjust dpcd_lane_adjust[LANE_COUNT_DP_MAX] = {0};
+
+	retries_cr = 0;
+	retry_count = 0;
+
+	memset(&dpcd_lane_status, '\0', sizeof(dpcd_lane_status));
+	memset(&dpcd_lane_status_updated, '\0',
+	sizeof(dpcd_lane_status_updated));
+
+	if (!link->ctx->dc->work_arounds.lt_early_cr_pattern)
+		dp_set_hw_training_pattern(link, link_res, lt_settings->pattern_for_cr, offset);
+
+	/* najeeb - The synaptics MST hub can put the LT in
+	* infinite loop by switching the VS
+	*/
+	/* between level 0 and level 1 continuously, here
+	* we try for CR lock for LinkTrainingMaxCRRetry count*/
+	while ((retries_cr < LINK_TRAINING_MAX_RETRY_COUNT) &&
+		(retry_count < LINK_TRAINING_MAX_CR_RETRY)) {
+
+
+		/* 1. call HWSS to set lane settings*/
+		dp_set_hw_lane_settings(
+				link,
+				link_res,
+				lt_settings,
+				offset);
+
+		/* 2. update DPCD of the receiver*/
+		if (!retry_count)
+			/* EPR #361076 - write as a 5-byte burst,
+			 * but only for the 1-st iteration.*/
+			dpcd_set_lt_pattern_and_lane_settings(
+					link,
+					lt_settings,
+					lt_settings->pattern_for_cr,
+					offset);
+		else
+			dpcd_set_lane_settings(
+					link,
+					lt_settings,
+					offset);
+
+		/* 3. wait receiver to lock-on*/
+		wait_time_microsec = lt_settings->cr_pattern_time;
+
+		dp_wait_for_training_aux_rd_interval(
+				link,
+				wait_time_microsec);
+
+		/* 4. Read lane status and requested drive
+		* settings as set by the sink
+		*/
+		status = dp_get_lane_status_and_lane_adjust(
+				link,
+				lt_settings,
+				dpcd_lane_status,
+				&dpcd_lane_status_updated,
+				dpcd_lane_adjust,
+				offset);
+
+		if (dp_check_dpcd_reqeust_status(link, status))
+			return LINK_TRAINING_ABORT;
+
+		/* 5. check CR done*/
+		if (dp_is_cr_done(lane_count, dpcd_lane_status)) {
+			DC_LOG_HW_LINK_TRAINING("%s: Clock recovery OK\n", __func__);
+			return LINK_TRAINING_SUCCESS;
+		}
+
+		/* 6. max VS reached*/
+		if ((link_dp_get_encoding_format(&lt_settings->link_settings) ==
+				DP_8b_10b_ENCODING) &&
+				dp_is_max_vs_reached(lt_settings))
+			break;
+
+		/* 7. same lane settings*/
+		/* Note: settings are the same for all lanes,
+		 * so comparing first lane is sufficient*/
+		if ((link_dp_get_encoding_format(&lt_settings->link_settings) == DP_8b_10b_ENCODING) &&
+				lt_settings->dpcd_lane_settings[0].bits.VOLTAGE_SWING_SET ==
+						dpcd_lane_adjust[0].bits.VOLTAGE_SWING_LANE)
+			retries_cr++;
+		else if ((link_dp_get_encoding_format(&lt_settings->link_settings) == DP_128b_132b_ENCODING) &&
+				lt_settings->dpcd_lane_settings[0].tx_ffe.PRESET_VALUE ==
+						dpcd_lane_adjust[0].tx_ffe.PRESET_VALUE)
+			retries_cr++;
+		else
+			retries_cr = 0;
+
+		/* 8. update VS/PE/PC2 in lt_settings*/
+		dp_decide_lane_settings(lt_settings, dpcd_lane_adjust,
+				lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings);
+		retry_count++;
+	}
+
+	if (retry_count >= LINK_TRAINING_MAX_CR_RETRY) {
+		ASSERT(0);
+		DC_LOG_ERROR("%s: Link Training Error, could not get CR after %d tries. Possibly voltage swing issue",
+			__func__,
+			LINK_TRAINING_MAX_CR_RETRY);
+
+	}
+
+	return dp_get_cr_failure(lane_count, dpcd_lane_status);
+}
+
+enum link_training_result perform_8b_10b_channel_equalization_sequence(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	struct link_training_settings *lt_settings,
+	uint32_t offset)
+{
+	enum dc_status status;
+	enum dc_dp_training_pattern tr_pattern;
+	uint32_t retries_ch_eq;
+	uint32_t wait_time_microsec;
+	enum dc_lane_count lane_count = lt_settings->link_settings.lane_count;
+	union lane_align_status_updated dpcd_lane_status_updated = {0};
+	union lane_status dpcd_lane_status[LANE_COUNT_DP_MAX] = {0};
+	union lane_adjust dpcd_lane_adjust[LANE_COUNT_DP_MAX] = {0};
+
+	/* Note: also check that TPS4 is a supported feature*/
+	tr_pattern = lt_settings->pattern_for_eq;
+
+	if (is_repeater(lt_settings, offset) && link_dp_get_encoding_format(&lt_settings->link_settings) == DP_8b_10b_ENCODING)
+		tr_pattern = DP_TRAINING_PATTERN_SEQUENCE_4;
+
+	dp_set_hw_training_pattern(link, link_res, tr_pattern, offset);
+
+	for (retries_ch_eq = 0; retries_ch_eq <= LINK_TRAINING_MAX_RETRY_COUNT;
+		retries_ch_eq++) {
+
+		dp_set_hw_lane_settings(link, link_res, lt_settings, offset);
+
+		/* 2. update DPCD*/
+		if (!retries_ch_eq)
+			/* EPR #361076 - write as a 5-byte burst,
+			 * but only for the 1-st iteration
+			 */
+
+			dpcd_set_lt_pattern_and_lane_settings(
+				link,
+				lt_settings,
+				tr_pattern, offset);
+		else
+			dpcd_set_lane_settings(link, lt_settings, offset);
+
+		/* 3. wait for receiver to lock-on*/
+		wait_time_microsec = dp_get_eq_aux_rd_interval(link, lt_settings, offset, (uint8_t)retries_ch_eq);
+
+		dp_wait_for_training_aux_rd_interval(
+				link,
+				wait_time_microsec);
+
+		/* 4. Read lane status and requested
+		 * drive settings as set by the sink*/
+
+		status = dp_get_lane_status_and_lane_adjust(
+			link,
+			lt_settings,
+			dpcd_lane_status,
+			&dpcd_lane_status_updated,
+			dpcd_lane_adjust,
+			offset);
+
+		if (dp_check_dpcd_reqeust_status(link, status))
+			return LINK_TRAINING_ABORT;
+
+		/* 5. check CR done*/
+		if (!dp_is_cr_done(lane_count, dpcd_lane_status))
+			return dpcd_lane_status[0].bits.CR_DONE_0 ?
+					LINK_TRAINING_EQ_FAIL_CR_PARTIAL :
+					LINK_TRAINING_EQ_FAIL_CR;
+
+		/* 6. check CHEQ done*/
+		if (dp_is_ch_eq_done(lane_count, dpcd_lane_status) &&
+				dp_is_symbol_locked(lane_count, dpcd_lane_status) &&
+				dp_check_interlane_aligned(dpcd_lane_status_updated, link, (uint8_t)retries_ch_eq))
+			return LINK_TRAINING_SUCCESS;
+
+		/* 7. update VS/PE/PC2 in lt_settings*/
+		dp_decide_lane_settings(lt_settings, dpcd_lane_adjust,
+				lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings);
+	}
+
+	return LINK_TRAINING_EQ_FAIL_EQ;
+
+}
+
+enum link_training_result dp_perform_8b_10b_link_training(
+		struct dc_link *link,
+		const struct link_resource *link_res,
+		struct link_training_settings *lt_settings)
+{
+	enum link_training_result status = LINK_TRAINING_SUCCESS;
+
+	uint8_t repeater_cnt = dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
+	uint8_t repeater_id;
+	uint8_t lane = 0;
+
+	if (link->ctx->dc->work_arounds.lt_early_cr_pattern)
+		start_clock_recovery_pattern_early(link, link_res, lt_settings, DPRX);
+
+	/* 1. set link rate, lane count and spread. */
+	if (lt_settings->lttpr_early_tps2)
+		set_link_settings_and_perform_early_tps2_retimer_pre_lt_sequence(link, link_res, lt_settings, repeater_cnt);
+	else
+		dpcd_set_link_settings(link, lt_settings);
+
+	if (lt_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) {
+
+		/* 2. perform link training (set link training done
+		 *  to false is done as well)
+		 */
+
+		for (repeater_id = repeater_cnt; (repeater_id > 0 && status == LINK_TRAINING_SUCCESS);
+				repeater_id--) {
+			status = perform_8b_10b_clock_recovery_sequence(link, link_res, lt_settings, repeater_id);
+
+			if (status != LINK_TRAINING_SUCCESS) {
+				repeater_training_done(link, repeater_id);
+				break;
+			}
+
+			status = perform_8b_10b_channel_equalization_sequence(link,
+					link_res,
+					lt_settings,
+					repeater_id);
+			if (status == LINK_TRAINING_SUCCESS)
+				DC_LOG_HW_LINK_TRAINING("%s: Channel EQ done.\n", __func__);
+
+			repeater_training_done(link, repeater_id);
+
+			if (status != LINK_TRAINING_SUCCESS)
+				break;
+
+			for (lane = 0; lane < LANE_COUNT_DP_MAX; lane++) {
+				lt_settings->dpcd_lane_settings[lane].raw = 0;
+				lt_settings->hw_lane_settings[lane].VOLTAGE_SWING = 0;
+				lt_settings->hw_lane_settings[lane].PRE_EMPHASIS = 0;
+			}
+		}
+	}
+
+	if (status == LINK_TRAINING_SUCCESS) {
+		status = perform_8b_10b_clock_recovery_sequence(link, link_res, lt_settings, DPRX);
+		if (status == LINK_TRAINING_SUCCESS) {
+			status = perform_8b_10b_channel_equalization_sequence(link,
+					link_res,
+					lt_settings,
+					DPRX);
+			if (status == LINK_TRAINING_SUCCESS)
+				DC_LOG_HW_LINK_TRAINING("%s: Channel EQ done.\n", __func__);
+		}
+	}
+
+	return status;
+}

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_8b_10b.h

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+
+#ifndef __DC_LINK_DP_TRAINING_8B_10B_H__
+#define __DC_LINK_DP_TRAINING_8B_10B_H__
+#include "link_dp_training.h"
+
+/* to avoid infinite loop where-in the receiver
+ * switches between different VS
+ */
+#define LINK_TRAINING_MAX_CR_RETRY 100
+#define LINK_TRAINING_MAX_RETRY_COUNT 5
+
+enum link_training_result dp_perform_8b_10b_link_training(
+		struct dc_link *link,
+		const struct link_resource *link_res,
+		struct link_training_settings *lt_settings);
+
+enum link_training_result perform_8b_10b_clock_recovery_sequence(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	struct link_training_settings *lt_settings,
+	uint32_t offset);
+
+enum link_training_result perform_8b_10b_channel_equalization_sequence(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	struct link_training_settings *lt_settings,
+	uint32_t offset);
+
+enum lttpr_mode dp_decide_8b_10b_lttpr_mode(struct dc_link *link);
+
+void decide_8b_10b_training_settings(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	const struct dc_link_settings *link_setting,
+	struct link_training_settings *lt_settings);
+
+#endif /* __DC_LINK_DP_TRAINING_8B_10B_H__ */

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_auxless.c

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+/* FILE POLICY AND INTENDED USAGE:
+ *
+ */
+#include "link_dp_training_auxless.h"
+#include "link_dp_phy.h"
+#define DC_LOGGER \
+	link->ctx->logger
+bool dp_perform_link_training_skip_aux(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	const struct dc_link_settings *link_setting)
+{
+	struct link_training_settings lt_settings = {0};
+
+	dp_decide_training_settings(
+			link,
+			link_res,
+			link_setting,
+			&lt_settings);
+	override_training_settings(
+			link,
+			&link->preferred_training_settings,
+			&lt_settings);
+
+	/* 1. Perform_clock_recovery_sequence. */
+
+	/* transmit training pattern for clock recovery */
+	dp_set_hw_training_pattern(link, link_res, lt_settings.pattern_for_cr, DPRX);
+
+	/* call HWSS to set lane settings*/
+	dp_set_hw_lane_settings(link, link_res, &lt_settings, DPRX);
+
+	/* wait receiver to lock-on*/
+	dp_wait_for_training_aux_rd_interval(link, lt_settings.cr_pattern_time);
+
+	/* 2. Perform_channel_equalization_sequence. */
+
+	/* transmit training pattern for channel equalization. */
+	dp_set_hw_training_pattern(link, link_res, lt_settings.pattern_for_eq, DPRX);
+
+	/* call HWSS to set lane settings*/
+	dp_set_hw_lane_settings(link, link_res, &lt_settings, DPRX);
+
+	/* wait receiver to lock-on. */
+	dp_wait_for_training_aux_rd_interval(link, lt_settings.eq_pattern_time);
+
+	/* 3. Perform_link_training_int. */
+
+	/* Mainlink output idle pattern. */
+	dp_set_hw_test_pattern(link, link_res, DP_TEST_PATTERN_VIDEO_MODE, NULL, 0);
+
+	dp_log_training_result(link, &lt_settings, LINK_TRAINING_SUCCESS);
+
+	return true;
+}

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_auxless.h

@@ -0,0 +1,35 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+
+#ifndef __DC_LINK_DP_TRAINING_AUXLESS_H__
+#define __DC_LINK_DP_TRAINING_AUXLESS_H__
+#include "link_dp_training.h"
+
+bool dp_perform_link_training_skip_aux(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	const struct dc_link_settings *link_setting);
+#endif /* __DC_LINK_DP_TRAINING_AUXLESS_H__ */

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_dpia.h

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+
+#ifndef __DC_LINK_DP_TRAINING_DPIA_H__
+#define __DC_LINK_DP_TRAINING_DPIA_H__
+#include "link_dp_training.h"
+
+/* The approximate time (us) it takes to transmit 9 USB4 DP clock sync packets. */
+#define DPIA_CLK_SYNC_DELAY 16000
+
+/* Train DP tunneling link for USB4 DPIA display endpoint.
+ * DPIA equivalent of dc_link_dp_perfrorm_link_training.
+ * Aborts link training upon detection of sink unplug.
+ */
+enum link_training_result dpia_perform_link_training(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	const struct dc_link_settings *link_setting,
+	bool skip_video_pattern);
+
+void dpia_training_abort(
+		struct dc_link *link,
+		struct link_training_settings *lt_settings,
+		uint32_t hop);
+
+uint32_t dpia_get_eq_aux_rd_interval(
+		const struct dc_link *link,
+		const struct link_training_settings *lt_settings,
+		uint32_t hop);
+
+void dpia_set_tps_notification(
+		struct dc_link *link,
+		const struct link_training_settings *lt_settings,
+		uint8_t pattern,
+		uint32_t offset);
+
+#endif /* __DC_LINK_DP_TRAINING_DPIA_H__ */

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.c

@@ -0,0 +1,553 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+/* FILE POLICY AND INTENDED USAGE:
+ * This file implements 8b/10b link training specially modified to support an
+ * embedded retimer chip. This retimer chip is referred as fixed vs pe retimer.
+ * Unlike native dp connection this chip requires a modified link training
+ * protocol based on 8b/10b link training. Since this is a non standard sequence
+ * and we must support this hardware, we decided to isolate it in its own
+ * training sequence inside its own file.
+ */
+#include "link_dp_training_fixed_vs_pe_retimer.h"
+#include "link_dp_training_8b_10b.h"
+#include "link_dpcd.h"
+#include "link_dp_phy.h"
+#include "link_dp_capability.h"
+#include "link_ddc.h"
+
+#define DC_LOGGER \
+	link->ctx->logger
+
+void dp_fixed_vs_pe_read_lane_adjust(
+	struct dc_link *link,
+	union dpcd_training_lane dpcd_lane_adjust[LANE_COUNT_DP_MAX])
+{
+	const uint8_t vendor_lttpr_write_data_vs[3] = {0x0, 0x53, 0x63};
+	const uint8_t vendor_lttpr_write_data_pe[3] = {0x0, 0x54, 0x63};
+	uint8_t dprx_vs = 0;
+	uint8_t dprx_pe = 0;
+	uint8_t lane;
+
+	/* W/A to read lane settings requested by DPRX */
+	link_configure_fixed_vs_pe_retimer(link->ddc,
+			&vendor_lttpr_write_data_vs[0], sizeof(vendor_lttpr_write_data_vs));
+
+	link_query_fixed_vs_pe_retimer(link->ddc, &dprx_vs, 1);
+
+	link_configure_fixed_vs_pe_retimer(link->ddc,
+			&vendor_lttpr_write_data_pe[0], sizeof(vendor_lttpr_write_data_pe));
+
+	link_query_fixed_vs_pe_retimer(link->ddc, &dprx_pe, 1);
+
+	for (lane = 0; lane < LANE_COUNT_DP_MAX; lane++) {
+		dpcd_lane_adjust[lane].bits.VOLTAGE_SWING_SET  = (dprx_vs >> (2 * lane)) & 0x3;
+		dpcd_lane_adjust[lane].bits.PRE_EMPHASIS_SET = (dprx_pe >> (2 * lane)) & 0x3;
+	}
+}
+
+
+void dp_fixed_vs_pe_set_retimer_lane_settings(
+	struct dc_link *link,
+	const union dpcd_training_lane dpcd_lane_adjust[LANE_COUNT_DP_MAX],
+	uint8_t lane_count)
+{
+	const uint8_t vendor_lttpr_write_data_reset[4] = {0x1, 0x50, 0x63, 0xFF};
+	uint8_t vendor_lttpr_write_data_vs[4] = {0x1, 0x51, 0x63, 0x0};
+	uint8_t vendor_lttpr_write_data_pe[4] = {0x1, 0x52, 0x63, 0x0};
+	uint8_t lane = 0;
+
+	for (lane = 0; lane < lane_count; lane++) {
+		vendor_lttpr_write_data_vs[3] |=
+				dpcd_lane_adjust[lane].bits.VOLTAGE_SWING_SET << (2 * lane);
+		vendor_lttpr_write_data_pe[3] |=
+				dpcd_lane_adjust[lane].bits.PRE_EMPHASIS_SET << (2 * lane);
+	}
+
+	/* Force LTTPR to output desired VS and PE */
+	link_configure_fixed_vs_pe_retimer(link->ddc,
+			&vendor_lttpr_write_data_reset[0], sizeof(vendor_lttpr_write_data_reset));
+
+	link_configure_fixed_vs_pe_retimer(link->ddc,
+			&vendor_lttpr_write_data_vs[0], sizeof(vendor_lttpr_write_data_vs));
+
+	link_configure_fixed_vs_pe_retimer(link->ddc,
+			&vendor_lttpr_write_data_pe[0], sizeof(vendor_lttpr_write_data_pe));
+}
+
+static enum link_training_result perform_fixed_vs_pe_nontransparent_training_sequence(
+		struct dc_link *link,
+		const struct link_resource *link_res,
+		struct link_training_settings *lt_settings)
+{
+	enum link_training_result status = LINK_TRAINING_SUCCESS;
+	uint8_t lane = 0;
+	uint8_t toggle_rate = 0x6;
+	uint8_t target_rate = 0x6;
+	bool apply_toggle_rate_wa = false;
+	uint8_t repeater_cnt;
+	uint8_t repeater_id;
+
+	/* Fixed VS/PE specific: Force CR AUX RD Interval to at least 16ms */
+	if (lt_settings->cr_pattern_time < 16000)
+		lt_settings->cr_pattern_time = 16000;
+
+	/* Fixed VS/PE specific: Toggle link rate */
+	apply_toggle_rate_wa = ((link->vendor_specific_lttpr_link_rate_wa == target_rate) || (link->vendor_specific_lttpr_link_rate_wa == 0));
+	target_rate = get_dpcd_link_rate(&lt_settings->link_settings);
+	toggle_rate = (target_rate == 0x6) ? 0xA : 0x6;
+
+	if (apply_toggle_rate_wa)
+		lt_settings->link_settings.link_rate = toggle_rate;
+
+	if (link->ctx->dc->work_arounds.lt_early_cr_pattern)
+		start_clock_recovery_pattern_early(link, link_res, lt_settings, DPRX);
+
+	/* 1. set link rate, lane count and spread. */
+	dpcd_set_link_settings(link, lt_settings);
+
+	/* Fixed VS/PE specific: Toggle link rate back*/
+	if (apply_toggle_rate_wa) {
+		core_link_write_dpcd(
+				link,
+				DP_LINK_BW_SET,
+				&target_rate,
+				1);
+	}
+
+	link->vendor_specific_lttpr_link_rate_wa = target_rate;
+
+	if (lt_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) {
+
+		/* 2. perform link training (set link training done
+		 *  to false is done as well)
+		 */
+		repeater_cnt = dp_parse_lttpr_repeater_count(link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
+
+		for (repeater_id = repeater_cnt; (repeater_id > 0 && status == LINK_TRAINING_SUCCESS);
+				repeater_id--) {
+			status = perform_8b_10b_clock_recovery_sequence(link, link_res, lt_settings, repeater_id);
+
+			if (status != LINK_TRAINING_SUCCESS) {
+				repeater_training_done(link, repeater_id);
+				break;
+			}
+
+			status = perform_8b_10b_channel_equalization_sequence(link,
+					link_res,
+					lt_settings,
+					repeater_id);
+
+			repeater_training_done(link, repeater_id);
+
+			if (status != LINK_TRAINING_SUCCESS)
+				break;
+
+			for (lane = 0; lane < LANE_COUNT_DP_MAX; lane++) {
+				lt_settings->dpcd_lane_settings[lane].raw = 0;
+				lt_settings->hw_lane_settings[lane].VOLTAGE_SWING = 0;
+				lt_settings->hw_lane_settings[lane].PRE_EMPHASIS = 0;
+			}
+		}
+	}
+
+	if (status == LINK_TRAINING_SUCCESS) {
+		status = perform_8b_10b_clock_recovery_sequence(link, link_res, lt_settings, DPRX);
+		if (status == LINK_TRAINING_SUCCESS) {
+			status = perform_8b_10b_channel_equalization_sequence(link,
+								       link_res,
+								       lt_settings,
+								       DPRX);
+		}
+	}
+
+	return status;
+}
+
+enum link_training_result dp_perform_fixed_vs_pe_training_sequence(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	struct link_training_settings *lt_settings)
+{
+	const uint8_t vendor_lttpr_write_data_reset[4] = {0x1, 0x50, 0x63, 0xFF};
+	const uint8_t offset = dp_parse_lttpr_repeater_count(
+			link->dpcd_caps.lttpr_caps.phy_repeater_cnt);
+	const uint8_t vendor_lttpr_write_data_intercept_en[4] = {0x1, 0x55, 0x63, 0x0};
+	const uint8_t vendor_lttpr_write_data_intercept_dis[4] = {0x1, 0x55, 0x63, 0x6E};
+	const uint8_t vendor_lttpr_write_data_adicora_eq1[4] = {0x1, 0x55, 0x63, 0x2E};
+	const uint8_t vendor_lttpr_write_data_adicora_eq2[4] = {0x1, 0x55, 0x63, 0x01};
+	const uint8_t vendor_lttpr_write_data_adicora_eq3[4] = {0x1, 0x55, 0x63, 0x68};
+	uint32_t pre_disable_intercept_delay_ms = 0;
+	uint8_t vendor_lttpr_write_data_vs[4] = {0x1, 0x51, 0x63, 0x0};
+	uint8_t vendor_lttpr_write_data_pe[4] = {0x1, 0x52, 0x63, 0x0};
+	const uint8_t vendor_lttpr_write_data_4lane_1[4] = {0x1, 0x6E, 0xF2, 0x19};
+	const uint8_t vendor_lttpr_write_data_4lane_2[4] = {0x1, 0x6B, 0xF2, 0x01};
+	const uint8_t vendor_lttpr_write_data_4lane_3[4] = {0x1, 0x6D, 0xF2, 0x18};
+	const uint8_t vendor_lttpr_write_data_4lane_4[4] = {0x1, 0x6C, 0xF2, 0x03};
+	const uint8_t vendor_lttpr_write_data_4lane_5[4] = {0x1, 0x03, 0xF3, 0x06};
+	const uint8_t vendor_lttpr_write_data_dpmf[4] = {0x1, 0x6, 0x70, 0x87};
+	enum link_training_result status = LINK_TRAINING_SUCCESS;
+	uint8_t lane = 0;
+	union down_spread_ctrl downspread = {0};
+	union lane_count_set lane_count_set = {0};
+	uint8_t toggle_rate;
+	uint8_t rate;
+
+	/* Only 8b/10b is supported */
+	ASSERT(link_dp_get_encoding_format(&lt_settings->link_settings) ==
+			DP_8b_10b_ENCODING);
+
+	if (lt_settings->lttpr_mode == LTTPR_MODE_NON_TRANSPARENT) {
+		status = perform_fixed_vs_pe_nontransparent_training_sequence(link, link_res, lt_settings);
+		return status;
+	}
+
+	if (offset != 0xFF) {
+		if (offset == 2) {
+			pre_disable_intercept_delay_ms = link->dc->debug.fixed_vs_aux_delay_config_wa;
+
+		/* Certain display and cable configuration require extra delay */
+		} else if (offset > 2) {
+			pre_disable_intercept_delay_ms = link->dc->debug.fixed_vs_aux_delay_config_wa * 2;
+		}
+	}
+
+	/* Vendor specific: Reset lane settings */
+	link_configure_fixed_vs_pe_retimer(link->ddc,
+			&vendor_lttpr_write_data_reset[0], sizeof(vendor_lttpr_write_data_reset));
+	link_configure_fixed_vs_pe_retimer(link->ddc,
+			&vendor_lttpr_write_data_vs[0], sizeof(vendor_lttpr_write_data_vs));
+	link_configure_fixed_vs_pe_retimer(link->ddc,
+			&vendor_lttpr_write_data_pe[0], sizeof(vendor_lttpr_write_data_pe));
+
+	/* Vendor specific: Enable intercept */
+	link_configure_fixed_vs_pe_retimer(link->ddc,
+			&vendor_lttpr_write_data_intercept_en[0], sizeof(vendor_lttpr_write_data_intercept_en));
+
+	/* 1. set link rate, lane count and spread. */
+
+	downspread.raw = (uint8_t)(lt_settings->link_settings.link_spread);
+
+	lane_count_set.bits.LANE_COUNT_SET =
+	lt_settings->link_settings.lane_count;
+
+	lane_count_set.bits.ENHANCED_FRAMING = lt_settings->enhanced_framing;
+	lane_count_set.bits.POST_LT_ADJ_REQ_GRANTED = 0;
+
+
+	if (lt_settings->pattern_for_eq < DP_TRAINING_PATTERN_SEQUENCE_4) {
+		lane_count_set.bits.POST_LT_ADJ_REQ_GRANTED =
+				link->dpcd_caps.max_ln_count.bits.POST_LT_ADJ_REQ_SUPPORTED;
+	}
+
+	core_link_write_dpcd(link, DP_DOWNSPREAD_CTRL,
+		&downspread.raw, sizeof(downspread));
+
+	core_link_write_dpcd(link, DP_LANE_COUNT_SET,
+		&lane_count_set.raw, 1);
+
+	rate = get_dpcd_link_rate(&lt_settings->link_settings);
+
+	// Only perform toggle if FIXED_VS LTTPR reports no IEEE OUI
+	if (memcmp("\x00\x00\x00", &link->dpcd_caps.lttpr_caps.lttpr_ieee_oui[0], 3) == 0) {
+		/* Vendor specific: Toggle link rate */
+		toggle_rate = (rate == 0x6) ? 0xA : 0x6;
+
+		if (link->vendor_specific_lttpr_link_rate_wa == rate || link->vendor_specific_lttpr_link_rate_wa == 0) {
+			core_link_write_dpcd(
+					link,
+					DP_LINK_BW_SET,
+					&toggle_rate,
+					1);
+		}
+
+		link->vendor_specific_lttpr_link_rate_wa = rate;
+	}
+
+	core_link_write_dpcd(link, DP_LINK_BW_SET, &rate, 1);
+
+	DC_LOG_HW_LINK_TRAINING("%s\n %x rate = %x\n %x lane = %x framing = %x\n %x spread = %x\n",
+		__func__,
+		DP_LINK_BW_SET,
+		lt_settings->link_settings.link_rate,
+		DP_LANE_COUNT_SET,
+		lt_settings->link_settings.lane_count,
+		lt_settings->enhanced_framing,
+		DP_DOWNSPREAD_CTRL,
+		lt_settings->link_settings.link_spread);
+
+	link_configure_fixed_vs_pe_retimer(link->ddc,
+			&vendor_lttpr_write_data_dpmf[0],
+			sizeof(vendor_lttpr_write_data_dpmf));
+
+	if (lt_settings->link_settings.lane_count == LANE_COUNT_FOUR) {
+		link_configure_fixed_vs_pe_retimer(link->ddc,
+				&vendor_lttpr_write_data_4lane_1[0], sizeof(vendor_lttpr_write_data_4lane_1));
+		link_configure_fixed_vs_pe_retimer(link->ddc,
+				&vendor_lttpr_write_data_4lane_2[0], sizeof(vendor_lttpr_write_data_4lane_2));
+		link_configure_fixed_vs_pe_retimer(link->ddc,
+				&vendor_lttpr_write_data_4lane_3[0], sizeof(vendor_lttpr_write_data_4lane_3));
+		link_configure_fixed_vs_pe_retimer(link->ddc,
+				&vendor_lttpr_write_data_4lane_4[0], sizeof(vendor_lttpr_write_data_4lane_4));
+		link_configure_fixed_vs_pe_retimer(link->ddc,
+				&vendor_lttpr_write_data_4lane_5[0], sizeof(vendor_lttpr_write_data_4lane_5));
+	}
+
+	/* 2. Perform link training */
+
+	/* Perform Clock Recovery Sequence */
+	if (status == LINK_TRAINING_SUCCESS) {
+		const uint8_t max_vendor_dpcd_retries = 10;
+		uint32_t retries_cr;
+		uint32_t retry_count;
+		uint32_t wait_time_microsec;
+		enum dc_lane_count lane_count = lt_settings->link_settings.lane_count;
+		union lane_status dpcd_lane_status[LANE_COUNT_DP_MAX];
+		union lane_align_status_updated dpcd_lane_status_updated;
+		union lane_adjust dpcd_lane_adjust[LANE_COUNT_DP_MAX] = {0};
+		uint8_t i = 0;
+
+		retries_cr = 0;
+		retry_count = 0;
+
+		memset(&dpcd_lane_status, '\0', sizeof(dpcd_lane_status));
+		memset(&dpcd_lane_status_updated, '\0',
+		sizeof(dpcd_lane_status_updated));
+
+		while ((retries_cr < LINK_TRAINING_MAX_RETRY_COUNT) &&
+			(retry_count < LINK_TRAINING_MAX_CR_RETRY)) {
+
+
+			/* 1. call HWSS to set lane settings */
+			dp_set_hw_lane_settings(
+					link,
+					link_res,
+					lt_settings,
+					0);
+
+			/* 2. update DPCD of the receiver */
+			if (!retry_count) {
+				/* EPR #361076 - write as a 5-byte burst,
+				 * but only for the 1-st iteration.
+				 */
+				dpcd_set_lt_pattern_and_lane_settings(
+						link,
+						lt_settings,
+						lt_settings->pattern_for_cr,
+						0);
+				/* Vendor specific: Disable intercept */
+				for (i = 0; i < max_vendor_dpcd_retries; i++) {
+					if (pre_disable_intercept_delay_ms != 0)
+						msleep(pre_disable_intercept_delay_ms);
+					if (link_configure_fixed_vs_pe_retimer(link->ddc,
+							&vendor_lttpr_write_data_intercept_dis[0],
+							sizeof(vendor_lttpr_write_data_intercept_dis)))
+						break;
+
+					link_configure_fixed_vs_pe_retimer(link->ddc,
+							&vendor_lttpr_write_data_intercept_en[0],
+							sizeof(vendor_lttpr_write_data_intercept_en));
+				}
+			} else {
+				vendor_lttpr_write_data_vs[3] = 0;
+				vendor_lttpr_write_data_pe[3] = 0;
+
+				for (lane = 0; lane < lane_count; lane++) {
+					vendor_lttpr_write_data_vs[3] |=
+							lt_settings->dpcd_lane_settings[lane].bits.VOLTAGE_SWING_SET << (2 * lane);
+					vendor_lttpr_write_data_pe[3] |=
+							lt_settings->dpcd_lane_settings[lane].bits.PRE_EMPHASIS_SET << (2 * lane);
+				}
+
+				/* Vendor specific: Update VS and PE to DPRX requested value */
+				link_configure_fixed_vs_pe_retimer(link->ddc,
+						&vendor_lttpr_write_data_vs[0], sizeof(vendor_lttpr_write_data_vs));
+				link_configure_fixed_vs_pe_retimer(link->ddc,
+						&vendor_lttpr_write_data_pe[0], sizeof(vendor_lttpr_write_data_pe));
+
+				dpcd_set_lane_settings(
+						link,
+						lt_settings,
+						0);
+			}
+
+			/* 3. wait receiver to lock-on*/
+			wait_time_microsec = lt_settings->cr_pattern_time;
+
+			dp_wait_for_training_aux_rd_interval(
+					link,
+					wait_time_microsec);
+
+			/* 4. Read lane status and requested drive
+			 * settings as set by the sink
+			 */
+			dp_get_lane_status_and_lane_adjust(
+					link,
+					lt_settings,
+					dpcd_lane_status,
+					&dpcd_lane_status_updated,
+					dpcd_lane_adjust,
+					0);
+
+			/* 5. check CR done*/
+			if (dp_is_cr_done(lane_count, dpcd_lane_status)) {
+				break;
+			}
+
+			/* 6. max VS reached*/
+			if (dp_is_max_vs_reached(lt_settings))
+				break;
+
+			/* 7. same lane settings */
+			/* Note: settings are the same for all lanes,
+			 * so comparing first lane is sufficient
+			 */
+			if (lt_settings->dpcd_lane_settings[0].bits.VOLTAGE_SWING_SET ==
+					dpcd_lane_adjust[0].bits.VOLTAGE_SWING_LANE)
+				retries_cr++;
+			else
+				retries_cr = 0;
+
+			/* 8. update VS/PE/PC2 in lt_settings*/
+			dp_decide_lane_settings(lt_settings, dpcd_lane_adjust,
+					lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings);
+			retry_count++;
+		}
+
+		if (retry_count >= LINK_TRAINING_MAX_CR_RETRY) {
+			ASSERT(0);
+			DC_LOG_ERROR("%s: Link Training Error, could not get CR after %d tries. Possibly voltage swing issue",
+				__func__,
+				LINK_TRAINING_MAX_CR_RETRY);
+
+		}
+
+		status = dp_get_cr_failure(lane_count, dpcd_lane_status);
+	}
+
+	/* Perform Channel EQ Sequence */
+	if (status == LINK_TRAINING_SUCCESS) {
+		enum dc_dp_training_pattern tr_pattern;
+		uint32_t retries_ch_eq;
+		uint32_t wait_time_microsec;
+		enum dc_lane_count lane_count = lt_settings->link_settings.lane_count;
+		union lane_align_status_updated dpcd_lane_status_updated = {0};
+		union lane_status dpcd_lane_status[LANE_COUNT_DP_MAX] = {0};
+		union lane_adjust dpcd_lane_adjust[LANE_COUNT_DP_MAX] = {0};
+
+		link_configure_fixed_vs_pe_retimer(link->ddc,
+				&vendor_lttpr_write_data_adicora_eq1[0],
+				sizeof(vendor_lttpr_write_data_adicora_eq1));
+		link_configure_fixed_vs_pe_retimer(link->ddc,
+				&vendor_lttpr_write_data_adicora_eq2[0],
+				sizeof(vendor_lttpr_write_data_adicora_eq2));
+
+
+		/* Note: also check that TPS4 is a supported feature*/
+		tr_pattern = lt_settings->pattern_for_eq;
+
+		dp_set_hw_training_pattern(link, link_res, tr_pattern, 0);
+
+		status = LINK_TRAINING_EQ_FAIL_EQ;
+
+		for (retries_ch_eq = 0; retries_ch_eq <= LINK_TRAINING_MAX_RETRY_COUNT;
+			retries_ch_eq++) {
+
+			dp_set_hw_lane_settings(link, link_res, lt_settings, 0);
+
+			vendor_lttpr_write_data_vs[3] = 0;
+			vendor_lttpr_write_data_pe[3] = 0;
+
+			for (lane = 0; lane < lane_count; lane++) {
+				vendor_lttpr_write_data_vs[3] |=
+						lt_settings->dpcd_lane_settings[lane].bits.VOLTAGE_SWING_SET << (2 * lane);
+				vendor_lttpr_write_data_pe[3] |=
+						lt_settings->dpcd_lane_settings[lane].bits.PRE_EMPHASIS_SET << (2 * lane);
+			}
+
+			/* Vendor specific: Update VS and PE to DPRX requested value */
+			link_configure_fixed_vs_pe_retimer(link->ddc,
+					&vendor_lttpr_write_data_vs[0], sizeof(vendor_lttpr_write_data_vs));
+			link_configure_fixed_vs_pe_retimer(link->ddc,
+					&vendor_lttpr_write_data_pe[0], sizeof(vendor_lttpr_write_data_pe));
+
+			/* 2. update DPCD*/
+			if (!retries_ch_eq) {
+				/* EPR #361076 - write as a 5-byte burst,
+				 * but only for the 1-st iteration
+				 */
+
+				dpcd_set_lt_pattern_and_lane_settings(
+					link,
+					lt_settings,
+					tr_pattern, 0);
+
+				link_configure_fixed_vs_pe_retimer(link->ddc,
+						&vendor_lttpr_write_data_adicora_eq3[0],
+						sizeof(vendor_lttpr_write_data_adicora_eq3));
+
+			} else
+				dpcd_set_lane_settings(link, lt_settings, 0);
+
+			/* 3. wait for receiver to lock-on*/
+			wait_time_microsec = lt_settings->eq_pattern_time;
+
+			dp_wait_for_training_aux_rd_interval(
+					link,
+					wait_time_microsec);
+
+			/* 4. Read lane status and requested
+			 * drive settings as set by the sink
+			 */
+			dp_get_lane_status_and_lane_adjust(
+				link,
+				lt_settings,
+				dpcd_lane_status,
+				&dpcd_lane_status_updated,
+				dpcd_lane_adjust,
+				0);
+
+			/* 5. check CR done*/
+			if (!dp_is_cr_done(lane_count, dpcd_lane_status)) {
+				status = LINK_TRAINING_EQ_FAIL_CR;
+				break;
+			}
+
+			/* 6. check CHEQ done*/
+			if (dp_is_ch_eq_done(lane_count, dpcd_lane_status) &&
+					dp_is_symbol_locked(lane_count, dpcd_lane_status) &&
+					dp_is_interlane_aligned(dpcd_lane_status_updated)) {
+				status = LINK_TRAINING_SUCCESS;
+				break;
+			}
+
+			/* 7. update VS/PE/PC2 in lt_settings*/
+			dp_decide_lane_settings(lt_settings, dpcd_lane_adjust,
+					lt_settings->hw_lane_settings, lt_settings->dpcd_lane_settings);
+		}
+	}
+
+	return status;
+}

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dp_training_fixed_vs_pe_retimer.h

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+
+#ifndef __DC_LINK_DP_FIXED_VS_PE_RETIMER_H__
+#define __DC_LINK_DP_FIXED_VS_PE_RETIMER_H__
+#include "link_dp_training.h"
+
+enum link_training_result dp_perform_fixed_vs_pe_training_sequence(
+	struct dc_link *link,
+	const struct link_resource *link_res,
+	struct link_training_settings *lt_settings);
+
+void dp_fixed_vs_pe_set_retimer_lane_settings(
+	struct dc_link *link,
+	const union dpcd_training_lane dpcd_lane_adjust[LANE_COUNT_DP_MAX],
+	uint8_t lane_count);
+
+void dp_fixed_vs_pe_read_lane_adjust(
+	struct dc_link *link,
+	union dpcd_training_lane dpcd_lane_adjust[LANE_COUNT_DP_MAX]);
+
+#endif /* __DC_LINK_DP_FIXED_VS_PE_RETIMER_H__ */

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dpcd.c

@@ -0,0 +1,251 @@
+/*
+ * Copyright 2021 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+/* FILE POLICY AND INTENDED USAGE:
+ *
+ * This file implements basic dpcd read/write functionality. It also does basic
+ * dpcd range check to ensure that every dpcd request is compliant with specs
+ * range requirements.
+ */
+
+#include "link_dpcd.h"
+#include <drm/display/drm_dp_helper.h>
+#include "dm_helpers.h"
+
+#define END_ADDRESS(start, size) (start + size - 1)
+#define ADDRESS_RANGE_SIZE(start, end) (end - start + 1)
+struct dpcd_address_range {
+	uint32_t start;
+	uint32_t end;
+};
+
+static enum dc_status internal_link_read_dpcd(
+	struct dc_link *link,
+	uint32_t address,
+	uint8_t *data,
+	uint32_t size)
+{
+	if (!link->aux_access_disabled &&
+			!dm_helpers_dp_read_dpcd(link->ctx,
+			link, address, data, size)) {
+		return DC_ERROR_UNEXPECTED;
+	}
+
+	return DC_OK;
+}
+
+static enum dc_status internal_link_write_dpcd(
+	struct dc_link *link,
+	uint32_t address,
+	const uint8_t *data,
+	uint32_t size)
+{
+	if (!link->aux_access_disabled &&
+			!dm_helpers_dp_write_dpcd(link->ctx,
+			link, address, data, size)) {
+		return DC_ERROR_UNEXPECTED;
+	}
+
+	return DC_OK;
+}
+
+/*
+ * Partition the entire DPCD address space
+ * XXX: This partitioning must cover the entire DPCD address space,
+ * and must contain no gaps or overlapping address ranges.
+ */
+static const struct dpcd_address_range mandatory_dpcd_partitions[] = {
+	{ 0, DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR1) - 1},
+	{ DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR1), DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR2) - 1 },
+	{ DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR2), DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR3) - 1 },
+	{ DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR3), DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR4) - 1 },
+	{ DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR4), DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR5) - 1 },
+	{ DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR5), DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR6) - 1 },
+	{ DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR6), DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR7) - 1 },
+	{ DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR7), DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR8) - 1 },
+	{ DP_TRAINING_PATTERN_SET_PHY_REPEATER(DP_PHY_LTTPR8), DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR1) - 1 },
+	/*
+	 * The FEC registers are contiguous
+	 */
+	{ DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR1), DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR1) - 1 },
+	{ DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR2), DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR2) - 1 },
+	{ DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR3), DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR3) - 1 },
+	{ DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR4), DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR4) - 1 },
+	{ DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR5), DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR5) - 1 },
+	{ DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR6), DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR6) - 1 },
+	{ DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR7), DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR7) - 1 },
+	{ DP_FEC_STATUS_PHY_REPEATER(DP_PHY_LTTPR8), DP_LTTPR_MAX_ADD },
+	/* all remaining DPCD addresses */
+	{ DP_LTTPR_MAX_ADD + 1, DP_DPCD_MAX_ADD } };
+
+static inline bool do_addresses_intersect_with_range(
+		const struct dpcd_address_range *range,
+		const uint32_t start_address,
+		const uint32_t end_address)
+{
+	return start_address <= range->end && end_address >= range->start;
+}
+
+static uint32_t dpcd_get_next_partition_size(const uint32_t address, const uint32_t size)
+{
+	const uint32_t end_address = END_ADDRESS(address, size);
+	uint32_t partition_iterator = 0;
+
+	/*
+	 * find current partition
+	 * this loop spins forever if partition map above is not surjective
+	 */
+	while (!do_addresses_intersect_with_range(&mandatory_dpcd_partitions[partition_iterator],
+				address, end_address))
+		partition_iterator++;
+	if (end_address < mandatory_dpcd_partitions[partition_iterator].end)
+		return size;
+	return ADDRESS_RANGE_SIZE(address, mandatory_dpcd_partitions[partition_iterator].end);
+}
+
+/*
+ * Ranges of DPCD addresses that must be read in a single transaction
+ * XXX: Do not allow any two address ranges in this array to overlap
+ */
+static const struct dpcd_address_range mandatory_dpcd_blocks[] = {
+	{ DP_LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV, DP_PHY_REPEATER_128B132B_RATES }};
+
+/*
+ * extend addresses to read all mandatory blocks together
+ */
+static void dpcd_extend_address_range(
+		const uint32_t in_address,
+		uint8_t * const in_data,
+		const uint32_t in_size,
+		uint32_t *out_address,
+		uint8_t **out_data,
+		uint32_t *out_size)
+{
+	const uint32_t end_address = END_ADDRESS(in_address, in_size);
+	const struct dpcd_address_range *addr_range;
+	struct dpcd_address_range new_addr_range;
+	uint32_t i;
+
+	new_addr_range.start = in_address;
+	new_addr_range.end = end_address;
+	for (i = 0; i < ARRAY_SIZE(mandatory_dpcd_blocks); i++) {
+		addr_range = &mandatory_dpcd_blocks[i];
+		if (addr_range->start <= in_address && addr_range->end >= in_address)
+			new_addr_range.start = addr_range->start;
+
+		if (addr_range->start <= end_address && addr_range->end >= end_address)
+			new_addr_range.end = addr_range->end;
+	}
+	*out_address = in_address;
+	*out_size = in_size;
+	*out_data = in_data;
+	if (new_addr_range.start != in_address || new_addr_range.end != end_address) {
+		*out_address = new_addr_range.start;
+		*out_size = ADDRESS_RANGE_SIZE(new_addr_range.start, new_addr_range.end);
+		*out_data = kcalloc(*out_size, sizeof(**out_data), GFP_KERNEL);
+		ASSERT(*out_data);
+	}
+}
+
+/*
+ * Reduce the AUX reply down to the values the caller requested
+ */
+static void dpcd_reduce_address_range(
+		const uint32_t extended_address,
+		uint8_t * const extended_data,
+		const uint32_t extended_size,
+		const uint32_t reduced_address,
+		uint8_t * const reduced_data,
+		const uint32_t reduced_size)
+{
+	(void)extended_size;
+	const uint32_t offset = reduced_address - extended_address;
+
+	/*
+	 * If the address is same, address was not extended.
+	 * So we do not need to free any memory.
+	 * The data is in original buffer(reduced_data).
+	 */
+	if (extended_data == reduced_data)
+		return;
+
+	memcpy(&extended_data[offset], reduced_data, reduced_size);
+	kfree(extended_data);
+}
+
+enum dc_status core_link_read_dpcd(
+	struct dc_link *link,
+	uint32_t address,
+	uint8_t *data,
+	uint32_t size)
+{
+	uint32_t extended_address;
+	uint32_t partitioned_address;
+	uint8_t *extended_data;
+	uint32_t extended_size;
+	/* size of the remaining partitioned address space */
+	uint32_t size_left_to_read;
+	enum dc_status status = DC_ERROR_UNEXPECTED;
+	/* size of the next partition to be read from */
+	uint32_t partition_size;
+	uint32_t data_index = 0;
+
+	dpcd_extend_address_range(address, data, size, &extended_address, &extended_data, &extended_size);
+	partitioned_address = extended_address;
+	size_left_to_read = extended_size;
+	while (size_left_to_read) {
+		partition_size = dpcd_get_next_partition_size(partitioned_address, size_left_to_read);
+		status = internal_link_read_dpcd(link, partitioned_address, &extended_data[data_index], partition_size);
+		if (status != DC_OK)
+			break;
+		partitioned_address += partition_size;
+		data_index += partition_size;
+		size_left_to_read -= partition_size;
+	}
+	dpcd_reduce_address_range(extended_address, extended_data, extended_size, address, data, size);
+	return status;
+}
+
+enum dc_status core_link_write_dpcd(
+	struct dc_link *link,
+	uint32_t address,
+	const uint8_t *data,
+	uint32_t size)
+{
+	uint32_t partition_size;
+	uint32_t data_index = 0;
+	enum dc_status status = DC_ERROR_UNEXPECTED;
+
+	while (size) {
+		partition_size = dpcd_get_next_partition_size(address, size);
+		status = internal_link_write_dpcd(link, address, &data[data_index], partition_size);
+		if (status != DC_OK)
+			break;
+		address += partition_size;
+		data_index += partition_size;
+		size -= partition_size;
+	}
+	return status;
+}

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_dpcd.h

@@ -0,0 +1,42 @@
+/*
+ * Copyright 2021 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#ifndef __LINK_DPCD_H__
+#define __LINK_DPCD_H__
+#include "link_service.h"
+#include "dpcd_defs.h"
+
+enum dc_status core_link_read_dpcd(
+		struct dc_link *link,
+		uint32_t address,
+		uint8_t *data,
+		uint32_t size);
+
+enum dc_status core_link_write_dpcd(
+		struct dc_link *link,
+		uint32_t address,
+		const uint8_t *data,
+		uint32_t size);
+#endif

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_edp_panel_control.h

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+#ifndef __DC_LINK_EDP_PANEL_CONTROL_H__
+#define __DC_LINK_EDP_PANEL_CONTROL_H__
+#include "link_service.h"
+
+enum dp_panel_mode dp_get_panel_mode(struct dc_link *link);
+void dp_set_panel_mode(struct dc_link *link, enum dp_panel_mode panel_mode);
+bool set_default_brightness_aux(struct dc_link *link);
+bool is_smartmux_suported(struct dc_link *link);
+void edp_panel_backlight_power_on(struct dc_link *link, bool wait_for_hpd);
+int edp_get_backlight_level(const struct dc_link *link);
+bool edp_get_backlight_level_nits(struct dc_link *link,
+		uint32_t *backlight_millinits_avg,
+		uint32_t *backlight_millinits_peak);
+bool edp_set_backlight_level(const struct dc_link *link,
+		struct set_backlight_level_params *backlight_level_params);
+bool edp_set_backlight_level_nits(struct dc_link *link,
+		bool isHDR,
+		uint32_t backlight_millinits,
+		uint32_t transition_time_in_ms);
+int edp_get_target_backlight_pwm(const struct dc_link *link);
+bool edp_get_psr_state(const struct dc_link *link, enum dc_psr_state *state);
+bool edp_set_psr_allow_active(struct dc_link *link, const bool *allow_active,
+		bool wait, bool force_static, const unsigned int *power_opts);
+bool edp_setup_psr(struct dc_link *link,
+		const struct dc_stream_state *stream, struct psr_config *psr_config,
+		struct psr_context *psr_context);
+bool edp_set_sink_vtotal_in_psr_active(const struct dc_link *link,
+       uint16_t psr_vtotal_idle, uint16_t psr_vtotal_su);
+void edp_get_psr_residency(const struct dc_link *link, uint32_t *residency, enum psr_residency_mode mode);
+bool edp_set_replay_allow_active(struct dc_link *dc_link, const bool *enable,
+	bool wait, bool force_static, const unsigned int *power_opts);
+bool edp_send_replay_cmd(struct dc_link *link,
+			enum replay_FW_Message_type msg,
+			union dmub_replay_cmd_set *cmd_data);
+bool edp_set_coasting_vtotal(struct dc_link *link, uint32_t coasting_vtotal, uint16_t frame_skip_number);
+bool edp_replay_residency(const struct dc_link *link,
+	unsigned int *residency, const bool is_start, const enum pr_residency_mode mode);
+bool edp_get_replay_state(const struct dc_link *link, uint64_t *state);
+bool edp_set_replay_power_opt_and_coasting_vtotal(struct dc_link *link,
+	const unsigned int *power_opts, uint32_t coasting_vtotal, uint16_t frame_skip_number);
+bool edp_wait_for_t12(struct dc_link *link);
+bool edp_is_ilr_optimization_required(struct dc_link *link,
+       struct dc_crtc_timing *crtc_timing);
+bool edp_is_ilr_optimization_enabled(struct dc_link *link);
+enum dc_link_rate get_max_edp_link_rate(struct dc_link *link);
+bool edp_backlight_enable_aux(struct dc_link *link, bool enable);
+void edp_add_delay_for_T9(struct dc_link *link);
+bool edp_receiver_ready_T9(struct dc_link *link);
+bool edp_receiver_ready_T7(struct dc_link *link);
+bool edp_power_alpm_dpcd_enable(struct dc_link *link, bool enable);
+bool edp_setup_freesync_replay(struct dc_link *link, const struct dc_stream_state *stream);
+void edp_set_panel_power(struct dc_link *link, bool powerOn);
+void edp_set_panel_assr(struct dc_link *link, struct pipe_ctx *pipe_ctx,
+		enum dp_panel_mode *panel_mode, bool enable);
+#endif /* __DC_LINK_EDP_POWER_CONTROL_H__ */

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_hdmi_frl.h

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2023 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+#ifndef __LINK_HDMI_FRL_H__
+#define __LINK_HDMI_FRL_H__
+#include "link_service.h"
+enum clock_source_id hdmi_frl_find_matching_phypll(
+		struct dc_link *link);
+void hdmi_frl_LTS_clear_Update_flag(struct ddc_service *ddc_service);
+void hdmi_frl_poll_start(struct ddc_service *ddc_service);
+void hdmi_frl_LTS_clear_Link_Setting(struct ddc_service *ddc_service);
+void hdmi_frl_retrieve_link_cap(struct dc_link *link, struct dc_sink *sink);
+enum link_result hdmi_frl_perform_link_training_with_retries(
+	struct dc_link *link);
+enum link_result hdmi_frl_perform_link_training_with_fallback(
+	struct dc_link *link, struct link_resource *link_res,
+	enum clock_source_id frl_phy_clock_source_id);
+void hdmi_frl_verify_link_cap(struct dc_link *link,
+		struct dc_hdmi_frl_link_settings *known_limit_link_setting);
+void hdmi_frl_decide_link_settings(struct dc_stream_state *stream,
+	struct dc_hdmi_frl_link_settings *frl_link_settings,
+	struct dsc_padding_params *dsc_paddding_params);
+bool hdmi_frl_poll_status_flag(struct dc_link *link);
+struct dc_hdmi_frl_link_settings *hdmi_frl_get_verified_link_cap(
+		struct dc_link *link);
+void hdmi_frl_set_preferred_link_settings(struct dc *dc,
+		struct dc_hdmi_frl_link_settings *link_setting,
+		struct dc_hdmi_frl_link_training_overrides *lt_overrides,
+		struct dc_link *link);
+void hdmi_frl_write_read_request_enable(
+		struct ddc_service *ddc_service);
+#endif /* __LINK_HDMI_FRL_H__ */

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_hpd.c

@@ -0,0 +1,177 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+/* FILE POLICY AND INTENDED USAGE:
+ *
+ * This file implements functions that manage basic HPD components such as gpio.
+ * It also provides wrapper functions to execute HPD related programming. This
+ * file only manages basic HPD functionality. It doesn't manage detection or
+ * feature or signal specific HPD behaviors.
+ */
+#include "link_hpd.h"
+#include "gpio_service_interface.h"
+
+bool link_get_hpd_state(struct dc_link *link)
+{
+	if (link->link_enc)
+		return link->link_enc->funcs->get_hpd_state(link->link_enc);
+	else
+		return false;
+}
+
+void link_enable_hpd(const struct dc_link *link)
+{
+	if (link->link_enc)
+		link->link_enc->funcs->enable_hpd(link->link_enc);
+}
+
+void link_disable_hpd(const struct dc_link *link)
+{
+	if (link->link_enc)
+		link->link_enc->funcs->disable_hpd(link->link_enc);
+}
+
+void link_enable_hpd_filter(struct dc_link *link, bool enable)
+{
+	if (enable) {
+		link->is_hpd_filter_disabled = false;
+		program_hpd_filter(link);
+	} else {
+		link->is_hpd_filter_disabled = true;
+		if (link->link_enc)
+			link->link_enc->funcs->program_hpd_filter(link->link_enc, 0, 0);
+	}
+}
+
+bool program_hpd_filter(const struct dc_link *link)
+{
+	int delay_on_connect_in_ms = 0;
+	int delay_on_disconnect_in_ms = 0;
+
+	if (link->is_hpd_filter_disabled || !link->link_enc) {
+		ASSERT(link->link_enc);
+		return false;
+	}
+
+	/* Verify feature is supported */
+	switch (link->connector_signal) {
+	case SIGNAL_TYPE_DVI_SINGLE_LINK:
+	case SIGNAL_TYPE_DVI_DUAL_LINK:
+	case SIGNAL_TYPE_HDMI_TYPE_A:
+	case SIGNAL_TYPE_HDMI_FRL:
+		/* Program hpd filter */
+		delay_on_connect_in_ms = 500;
+		delay_on_disconnect_in_ms = 100;
+		break;
+	case SIGNAL_TYPE_DISPLAY_PORT:
+	case SIGNAL_TYPE_DISPLAY_PORT_MST:
+		/* Program hpd filter to allow DP signal to settle */
+		/* 500:	not able to detect MST <-> SST switch as HPD is low for
+		 * only 100ms on DELL U2413
+		 * 0: some passive dongle still show aux mode instead of i2c
+		 * 20-50: not enough to hide bouncing HPD with passive dongle.
+		 * also see intermittent i2c read issues.
+		 */
+		delay_on_connect_in_ms = 80;
+		delay_on_disconnect_in_ms = 0;
+		break;
+	case SIGNAL_TYPE_LVDS:
+	case SIGNAL_TYPE_EDP:
+	default:
+		/* Don't program hpd filter */
+		return false;
+	}
+
+	return link->link_enc->funcs->program_hpd_filter(link->link_enc, delay_on_connect_in_ms, delay_on_disconnect_in_ms);
+}
+
+struct gpio *link_get_hpd_gpio(struct dc_bios *dcb,
+			  struct graphics_object_id link_id,
+			  struct gpio_service *gpio_service)
+{
+	enum bp_result bp_result;
+	struct graphics_object_hpd_info hpd_info;
+	struct gpio_pin_info pin_info;
+
+	if (dcb->funcs->get_hpd_info(dcb, link_id, &hpd_info) != BP_RESULT_OK)
+		return NULL;
+
+	bp_result = dcb->funcs->get_gpio_pin_info(dcb,
+		hpd_info.hpd_int_gpio_uid, &pin_info);
+
+	if (bp_result != BP_RESULT_OK) {
+		return NULL;
+	}
+
+	return dal_gpio_service_create_irq(gpio_service,
+					   pin_info.offset,
+					   pin_info.mask);
+}
+
+enum hpd_source_id get_hpd_line(struct dc_link *link)
+{
+	struct gpio *hpd;
+	enum hpd_source_id hpd_id;
+
+		hpd_id = HPD_SOURCEID_UNKNOWN;
+
+	/* Use GPIO path where supported, otherwise use hardware encoder path */
+	if (link->ctx && link->ctx->dce_version <= DCN_VERSION_4_01) {
+		hpd = link_get_hpd_gpio(link->ctx->dc_bios, link->link_id,
+				   link->ctx->gpio_service);
+	} else {
+		hpd = NULL;
+	}
+
+	if (hpd) {
+		switch (dal_irq_get_source(hpd)) {
+		case DC_IRQ_SOURCE_HPD1:
+			hpd_id = HPD_SOURCEID1;
+		break;
+		case DC_IRQ_SOURCE_HPD2:
+			hpd_id = HPD_SOURCEID2;
+		break;
+		case DC_IRQ_SOURCE_HPD3:
+			hpd_id = HPD_SOURCEID3;
+		break;
+		case DC_IRQ_SOURCE_HPD4:
+			hpd_id = HPD_SOURCEID4;
+		break;
+		case DC_IRQ_SOURCE_HPD5:
+			hpd_id = HPD_SOURCEID5;
+		break;
+		case DC_IRQ_SOURCE_HPD6:
+			hpd_id = HPD_SOURCEID6;
+		break;
+		default:
+			BREAK_TO_DEBUGGER();
+		break;
+		}
+
+		dal_gpio_destroy_irq(&hpd);
+	}
+
+	return hpd_id;
+}

linux-7.2.3/drivers/gpu/drm/amd/display/dc/link/protocols/link_hpd.h

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2022 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+
+
+#ifndef __DC_LINK_HPD_H__
+#define __DC_LINK_HPD_H__
+#include "link_service.h"
+
+enum hpd_source_id get_hpd_line(struct dc_link *link);
+/*
+ *  Function: program_hpd_filter
+ *
+ *  @brief
+ *     Programs HPD filter on associated HPD line to default values.
+ *
+ *  @return
+ *     true on success, false otherwise
+ */
+bool program_hpd_filter(const struct dc_link *link);
+/* Query hot plug status of USB4 DP tunnel.
+ * Returns true if HPD high.
+ */
+bool dpia_query_hpd_status(struct dc_link *link);
+bool link_get_hpd_state(struct dc_link *link);
+struct gpio *link_get_hpd_gpio(struct dc_bios *dcb,
+		struct graphics_object_id link_id,
+		struct gpio_service *gpio_service);
+void link_enable_hpd(const struct dc_link *link);
+void link_disable_hpd(const struct dc_link *link);
+void link_enable_hpd_filter(struct dc_link *link, bool enable);
+#endif /* __DC_LINK_HPD_H__ */