Resguardo inicial

linux-7.2.3/drivers/rpmsg/Kconfig

@@ -0,0 +1,84 @@
+# SPDX-License-Identifier: GPL-2.0
+
+menu "Rpmsg drivers"
+
+# RPMSG always gets selected by whoever wants it
+config RPMSG
+	tristate
+
+config RPMSG_CHAR
+	tristate "RPMSG device interface"
+	depends on RPMSG
+	depends on NET
+	help
+	  Say Y here to export rpmsg endpoints as device files, usually found
+	  in /dev. They make it possible for user-space programs to send and
+	  receive rpmsg packets.
+
+config RPMSG_CTRL
+	tristate "RPMSG control interface"
+	depends on RPMSG && ( RPMSG_CHAR || RPMSG_CHAR=n )
+	help
+	  Say Y here to enable the support of the /dev/rpmsg_ctrlX API. This API
+	  allows user-space programs to create endpoints with specific service name,
+	  source and destination addresses.
+
+config RPMSG_NS
+	tristate "RPMSG name service announcement"
+	depends on RPMSG
+	help
+	  Say Y here to enable the support of the name service announcement
+	  channel that probes the associated RPMsg device on remote endpoint
+	  service announcement.
+
+config RPMSG_MTK_SCP
+	tristate "MediaTek SCP"
+	depends on MTK_SCP
+	select RPMSG
+	help
+	  Say y here to enable support providing communication channels to
+	  remote processors in MediaTek platforms.
+	  This use IPI and IPC to communicate with remote processors.
+
+config RPMSG_QCOM_GLINK
+	tristate
+	select RPMSG
+
+config RPMSG_QCOM_GLINK_RPM
+	tristate "Qualcomm RPM Glink driver"
+	select RPMSG_QCOM_GLINK
+	depends on HAS_IOMEM
+	depends on MAILBOX
+	help
+	  Say y here to enable support for the GLINK RPM communication driver,
+	  which serves as a channel for communication with the RPM in GLINK
+	  enabled systems.
+
+config RPMSG_QCOM_GLINK_SMEM
+	tristate "Qualcomm SMEM Glink driver"
+	select RPMSG_QCOM_GLINK
+	depends on MAILBOX
+	depends on QCOM_SMEM
+	help
+	  Say y here to enable support for the GLINK SMEM communication driver,
+	  which provides support for using the GLINK communication protocol
+	  over SMEM.
+
+config RPMSG_QCOM_SMD
+	tristate "Qualcomm Shared Memory Driver (SMD)"
+	depends on MAILBOX
+	depends on QCOM_SMEM
+	select RPMSG
+	help
+	  Say y here to enable support for the Qualcomm Shared Memory Driver
+	  providing communication channels to remote processors in Qualcomm
+	  platforms.
+
+config RPMSG_VIRTIO
+	tristate "Virtio RPMSG bus driver"
+	depends on HAS_DMA
+	select RPMSG
+	select RPMSG_NS
+	select VIRTIO
+
+endmenu

linux-7.2.3/drivers/rpmsg/Makefile

@@ -0,0 +1,13 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_RPMSG)		+= rpmsg_core.o
+obj-$(CONFIG_RPMSG_CHAR)	+= rpmsg_char.o
+obj-$(CONFIG_RPMSG_CTRL)	+= rpmsg_ctrl.o
+obj-$(CONFIG_RPMSG_NS)		+= rpmsg_ns.o
+obj-$(CONFIG_RPMSG_MTK_SCP)	+= mtk_rpmsg.o
+CFLAGS_qcom_glink_native.o	:= -I$(src)
+qcom_glink-objs			:= qcom_glink_native.o qcom_glink_ssr.o
+obj-$(CONFIG_RPMSG_QCOM_GLINK) += qcom_glink.o
+obj-$(CONFIG_RPMSG_QCOM_GLINK_RPM) += qcom_glink_rpm.o
+obj-$(CONFIG_RPMSG_QCOM_GLINK_SMEM) += qcom_glink_smem.o
+obj-$(CONFIG_RPMSG_QCOM_SMD)	+= qcom_smd.o
+obj-$(CONFIG_RPMSG_VIRTIO)	+= virtio_rpmsg_bus.o

linux-7.2.3/drivers/rpmsg/mtk_rpmsg.c

@@ -0,0 +1,410 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright 2019 Google LLC.
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/remoteproc.h>
+#include <linux/rpmsg/mtk_rpmsg.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+
+#include "rpmsg_internal.h"
+
+struct mtk_rpmsg_rproc_subdev {
+	struct platform_device *pdev;
+	struct mtk_rpmsg_info *info;
+	struct rpmsg_endpoint *ns_ept;
+	struct rproc_subdev subdev;
+
+	struct work_struct register_work;
+	struct list_head channels;
+	struct mutex channels_lock;
+};
+
+#define to_mtk_subdev(d) container_of(d, struct mtk_rpmsg_rproc_subdev, subdev)
+
+struct mtk_rpmsg_channel_info {
+	struct rpmsg_channel_info info;
+	bool registered;
+	struct list_head list;
+};
+
+/**
+ * struct rpmsg_ns_msg - dynamic name service announcement message
+ * @name: name of remote service that is published
+ * @addr: address of remote service that is published
+ *
+ * This message is sent across to publish a new service. When we receive these
+ * messages, an appropriate rpmsg channel (i.e device) is created. In turn, the
+ * ->probe() handler of the appropriate rpmsg driver will be invoked
+ *  (if/as-soon-as one is registered).
+ */
+struct rpmsg_ns_msg {
+	char name[RPMSG_NAME_SIZE];
+	u32 addr;
+} __packed;
+
+struct mtk_rpmsg_device {
+	struct rpmsg_device rpdev;
+	struct mtk_rpmsg_rproc_subdev *mtk_subdev;
+};
+
+struct mtk_rpmsg_endpoint {
+	struct rpmsg_endpoint ept;
+	struct mtk_rpmsg_rproc_subdev *mtk_subdev;
+};
+
+#define to_mtk_rpmsg_device(r) container_of(r, struct mtk_rpmsg_device, rpdev)
+#define to_mtk_rpmsg_endpoint(r) container_of(r, struct mtk_rpmsg_endpoint, ept)
+
+static const struct rpmsg_endpoint_ops mtk_rpmsg_endpoint_ops;
+
+static void __mtk_ept_release(struct kref *kref)
+{
+	struct rpmsg_endpoint *ept = container_of(kref, struct rpmsg_endpoint,
+						  refcount);
+	kfree(to_mtk_rpmsg_endpoint(ept));
+}
+
+static void mtk_rpmsg_ipi_handler(void *data, unsigned int len, void *priv)
+{
+	struct mtk_rpmsg_endpoint *mept = priv;
+	struct rpmsg_endpoint *ept = &mept->ept;
+	int ret;
+
+	ret = (*ept->cb)(ept->rpdev, data, len, ept->priv, ept->addr);
+	if (ret)
+		dev_warn(&ept->rpdev->dev, "rpmsg handler return error = %d",
+			 ret);
+}
+
+static struct rpmsg_endpoint *
+__mtk_create_ept(struct mtk_rpmsg_rproc_subdev *mtk_subdev,
+		 struct rpmsg_device *rpdev, rpmsg_rx_cb_t cb, void *priv,
+		 u32 id)
+{
+	struct mtk_rpmsg_endpoint *mept;
+	struct rpmsg_endpoint *ept;
+	struct platform_device *pdev = mtk_subdev->pdev;
+	int ret;
+
+	mept = kzalloc_obj(*mept);
+	if (!mept)
+		return NULL;
+	mept->mtk_subdev = mtk_subdev;
+
+	ept = &mept->ept;
+	kref_init(&ept->refcount);
+
+	ept->rpdev = rpdev;
+	ept->cb = cb;
+	ept->priv = priv;
+	ept->ops = &mtk_rpmsg_endpoint_ops;
+	ept->addr = id;
+
+	ret = mtk_subdev->info->register_ipi(pdev, id, mtk_rpmsg_ipi_handler,
+					     mept);
+	if (ret) {
+		dev_err(&pdev->dev, "IPI register failed, id = %d", id);
+		kref_put(&ept->refcount, __mtk_ept_release);
+		return NULL;
+	}
+
+	return ept;
+}
+
+static struct rpmsg_endpoint *
+mtk_rpmsg_create_ept(struct rpmsg_device *rpdev, rpmsg_rx_cb_t cb, void *priv,
+		     struct rpmsg_channel_info chinfo)
+{
+	struct mtk_rpmsg_rproc_subdev *mtk_subdev =
+		to_mtk_rpmsg_device(rpdev)->mtk_subdev;
+
+	return __mtk_create_ept(mtk_subdev, rpdev, cb, priv, chinfo.src);
+}
+
+static void mtk_rpmsg_destroy_ept(struct rpmsg_endpoint *ept)
+{
+	struct mtk_rpmsg_rproc_subdev *mtk_subdev =
+		to_mtk_rpmsg_endpoint(ept)->mtk_subdev;
+
+	mtk_subdev->info->unregister_ipi(mtk_subdev->pdev, ept->addr);
+	kref_put(&ept->refcount, __mtk_ept_release);
+}
+
+static int mtk_rpmsg_send(struct rpmsg_endpoint *ept, const void *data, int len)
+{
+	struct mtk_rpmsg_rproc_subdev *mtk_subdev =
+		to_mtk_rpmsg_endpoint(ept)->mtk_subdev;
+
+	return mtk_subdev->info->send_ipi(mtk_subdev->pdev, ept->addr, data,
+					  len, 0);
+}
+
+static int mtk_rpmsg_trysend(struct rpmsg_endpoint *ept, const void *data, int len)
+{
+	struct mtk_rpmsg_rproc_subdev *mtk_subdev =
+		to_mtk_rpmsg_endpoint(ept)->mtk_subdev;
+
+	/*
+	 * TODO: This currently is same as mtk_rpmsg_send, and wait until SCP
+	 * received the last command.
+	 */
+	return mtk_subdev->info->send_ipi(mtk_subdev->pdev, ept->addr, data,
+					  len, 0);
+}
+
+static const struct rpmsg_endpoint_ops mtk_rpmsg_endpoint_ops = {
+	.destroy_ept = mtk_rpmsg_destroy_ept,
+	.send = mtk_rpmsg_send,
+	.trysend = mtk_rpmsg_trysend,
+};
+
+static void mtk_rpmsg_release_device(struct device *dev)
+{
+	struct rpmsg_device *rpdev = to_rpmsg_device(dev);
+	struct mtk_rpmsg_device *mdev = to_mtk_rpmsg_device(rpdev);
+
+	kfree(mdev);
+}
+
+static const struct rpmsg_device_ops mtk_rpmsg_device_ops = {
+	.create_ept = mtk_rpmsg_create_ept,
+};
+
+static struct device_node *
+mtk_rpmsg_match_device_subnode(struct device_node *node, const char *channel)
+{
+	struct device_node *child;
+	const char *name;
+	int ret;
+
+	for_each_available_child_of_node(node, child) {
+		ret = of_property_read_string(child, "mediatek,rpmsg-name", &name);
+		if (ret)
+			continue;
+
+		if (strcmp(name, channel) == 0)
+			return child;
+	}
+
+	return NULL;
+}
+
+static int mtk_rpmsg_register_device(struct mtk_rpmsg_rproc_subdev *mtk_subdev,
+				     struct rpmsg_channel_info *info)
+{
+	struct rpmsg_device *rpdev;
+	struct mtk_rpmsg_device *mdev;
+	struct platform_device *pdev = mtk_subdev->pdev;
+
+	mdev = kzalloc_obj(*mdev);
+	if (!mdev)
+		return -ENOMEM;
+
+	mdev->mtk_subdev = mtk_subdev;
+
+	rpdev = &mdev->rpdev;
+	rpdev->ops = &mtk_rpmsg_device_ops;
+	rpdev->src = info->src;
+	rpdev->dst = info->dst;
+	strscpy(rpdev->id.name, info->name, RPMSG_NAME_SIZE);
+
+	rpdev->dev.of_node =
+		mtk_rpmsg_match_device_subnode(pdev->dev.of_node, info->name);
+	rpdev->dev.parent = &pdev->dev;
+	rpdev->dev.release = mtk_rpmsg_release_device;
+
+	return rpmsg_register_device(rpdev);
+}
+
+static void mtk_register_device_work_function(struct work_struct *register_work)
+{
+	struct mtk_rpmsg_rproc_subdev *subdev = container_of(
+		register_work, struct mtk_rpmsg_rproc_subdev, register_work);
+	struct platform_device *pdev = subdev->pdev;
+	struct mtk_rpmsg_channel_info *info;
+	int ret;
+
+	mutex_lock(&subdev->channels_lock);
+	list_for_each_entry(info, &subdev->channels, list) {
+		if (info->registered)
+			continue;
+
+		mutex_unlock(&subdev->channels_lock);
+		ret = mtk_rpmsg_register_device(subdev, &info->info);
+		mutex_lock(&subdev->channels_lock);
+		if (ret) {
+			dev_err(&pdev->dev, "Can't create rpmsg_device\n");
+			continue;
+		}
+
+		info->registered = true;
+	}
+	mutex_unlock(&subdev->channels_lock);
+}
+
+static int mtk_rpmsg_create_device(struct mtk_rpmsg_rproc_subdev *mtk_subdev,
+				   char *name, u32 addr)
+{
+	struct mtk_rpmsg_channel_info *info;
+
+	info = kzalloc_obj(*info);
+	if (!info)
+		return -ENOMEM;
+
+	strscpy(info->info.name, name, RPMSG_NAME_SIZE);
+	info->info.src = addr;
+	info->info.dst = RPMSG_ADDR_ANY;
+	mutex_lock(&mtk_subdev->channels_lock);
+	list_add(&info->list, &mtk_subdev->channels);
+	mutex_unlock(&mtk_subdev->channels_lock);
+
+	schedule_work(&mtk_subdev->register_work);
+	return 0;
+}
+
+static int mtk_rpmsg_ns_cb(struct rpmsg_device *rpdev, void *data, int len,
+			   void *priv, u32 src)
+{
+	struct rpmsg_ns_msg *msg = data;
+	struct mtk_rpmsg_rproc_subdev *mtk_subdev = priv;
+	struct device *dev = &mtk_subdev->pdev->dev;
+
+	int ret;
+
+	if (len != sizeof(*msg)) {
+		dev_err(dev, "malformed ns msg (%d)\n", len);
+		return -EINVAL;
+	}
+
+	/*
+	 * the name service ept does _not_ belong to a real rpmsg channel,
+	 * and is handled by the rpmsg bus itself.
+	 * for sanity reasons, make sure a valid rpdev has _not_ sneaked
+	 * in somehow.
+	 */
+	if (rpdev) {
+		dev_err(dev, "anomaly: ns ept has an rpdev handle\n");
+		return -EINVAL;
+	}
+
+	/* don't trust the remote processor for null terminating the name */
+	msg->name[RPMSG_NAME_SIZE - 1] = '\0';
+
+	dev_info(dev, "creating channel %s addr 0x%x\n", msg->name, msg->addr);
+
+	ret = mtk_rpmsg_create_device(mtk_subdev, msg->name, msg->addr);
+	if (ret) {
+		dev_err(dev, "create rpmsg device failed\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int mtk_rpmsg_prepare(struct rproc_subdev *subdev)
+{
+	struct mtk_rpmsg_rproc_subdev *mtk_subdev = to_mtk_subdev(subdev);
+
+	/* a dedicated endpoint handles the name service msgs */
+	if (mtk_subdev->info->ns_ipi_id >= 0) {
+		mtk_subdev->ns_ept =
+			__mtk_create_ept(mtk_subdev, NULL, mtk_rpmsg_ns_cb,
+					 mtk_subdev,
+					 mtk_subdev->info->ns_ipi_id);
+		if (!mtk_subdev->ns_ept) {
+			dev_err(&mtk_subdev->pdev->dev,
+				"failed to create name service endpoint\n");
+			return -ENOMEM;
+		}
+	}
+
+	return 0;
+}
+
+static void mtk_rpmsg_unprepare(struct rproc_subdev *subdev)
+{
+	struct mtk_rpmsg_rproc_subdev *mtk_subdev = to_mtk_subdev(subdev);
+
+	if (mtk_subdev->ns_ept) {
+		mtk_rpmsg_destroy_ept(mtk_subdev->ns_ept);
+		mtk_subdev->ns_ept = NULL;
+	}
+}
+
+static void mtk_rpmsg_stop(struct rproc_subdev *subdev, bool crashed)
+{
+	struct mtk_rpmsg_channel_info *info, *next;
+	struct mtk_rpmsg_rproc_subdev *mtk_subdev = to_mtk_subdev(subdev);
+	struct device *dev = &mtk_subdev->pdev->dev;
+
+	/*
+	 * Destroy the name service endpoint here, to avoid new channel being
+	 * created after the rpmsg_unregister_device loop below.
+	 */
+	if (mtk_subdev->ns_ept) {
+		mtk_rpmsg_destroy_ept(mtk_subdev->ns_ept);
+		mtk_subdev->ns_ept = NULL;
+	}
+
+	cancel_work_sync(&mtk_subdev->register_work);
+
+	mutex_lock(&mtk_subdev->channels_lock);
+	list_for_each_entry(info, &mtk_subdev->channels, list) {
+		if (!info->registered)
+			continue;
+		if (rpmsg_unregister_device(dev, &info->info)) {
+			dev_warn(
+				dev,
+				"rpmsg_unregister_device failed for %s.%d.%d\n",
+				info->info.name, info->info.src,
+				info->info.dst);
+		}
+	}
+
+	list_for_each_entry_safe(info, next,
+				 &mtk_subdev->channels, list) {
+		list_del(&info->list);
+		kfree(info);
+	}
+	mutex_unlock(&mtk_subdev->channels_lock);
+}
+
+struct rproc_subdev *
+mtk_rpmsg_create_rproc_subdev(struct platform_device *pdev,
+			      struct mtk_rpmsg_info *info)
+{
+	struct mtk_rpmsg_rproc_subdev *mtk_subdev;
+
+	mtk_subdev = kzalloc_obj(*mtk_subdev);
+	if (!mtk_subdev)
+		return NULL;
+
+	mtk_subdev->pdev = pdev;
+	mtk_subdev->subdev.prepare = mtk_rpmsg_prepare;
+	mtk_subdev->subdev.stop = mtk_rpmsg_stop;
+	mtk_subdev->subdev.unprepare = mtk_rpmsg_unprepare;
+	mtk_subdev->info = info;
+	INIT_LIST_HEAD(&mtk_subdev->channels);
+	INIT_WORK(&mtk_subdev->register_work,
+		  mtk_register_device_work_function);
+	mutex_init(&mtk_subdev->channels_lock);
+
+	return &mtk_subdev->subdev;
+}
+EXPORT_SYMBOL_GPL(mtk_rpmsg_create_rproc_subdev);
+
+void mtk_rpmsg_destroy_rproc_subdev(struct rproc_subdev *subdev)
+{
+	struct mtk_rpmsg_rproc_subdev *mtk_subdev = to_mtk_subdev(subdev);
+
+	kfree(mtk_subdev);
+}
+EXPORT_SYMBOL_GPL(mtk_rpmsg_destroy_rproc_subdev);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("MediaTek scp rpmsg driver");

linux-7.2.3/drivers/rpmsg/qcom_glink_native.h

@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2016-2017, Linaro Ltd
+ */
+
+#ifndef __QCOM_GLINK_NATIVE_H__
+#define __QCOM_GLINK_NATIVE_H__
+
+#include <linux/types.h>
+
+#define GLINK_FEATURE_INTENT_REUSE	BIT(0)
+#define GLINK_FEATURE_MIGRATION		BIT(1)
+#define GLINK_FEATURE_TRACER_PKT	BIT(2)
+
+struct qcom_glink_pipe {
+	size_t length;
+
+	size_t (*avail)(struct qcom_glink_pipe *glink_pipe);
+
+	void (*peek)(struct qcom_glink_pipe *glink_pipe, void *data,
+		     unsigned int offset, size_t count);
+	void (*advance)(struct qcom_glink_pipe *glink_pipe, size_t count);
+
+	void (*write)(struct qcom_glink_pipe *glink_pipe,
+		      const void *hdr, size_t hlen,
+		      const void *data, size_t dlen);
+	void (*kick)(struct qcom_glink_pipe *glink_pipe);
+};
+
+struct device;
+struct qcom_glink;
+
+struct qcom_glink *qcom_glink_native_probe(struct device *dev,
+					   unsigned long features,
+					   struct qcom_glink_pipe *rx,
+					   struct qcom_glink_pipe *tx,
+					   bool intentless);
+void qcom_glink_native_remove(struct qcom_glink *glink);
+void qcom_glink_native_rx(struct qcom_glink *glink);
+
+#endif

linux-7.2.3/drivers/rpmsg/qcom_glink_rpm.c

@@ -0,0 +1,405 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2016-2017, Linaro Ltd
+ */
+
+#include <linux/idr.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/list.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/rpmsg.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/mailbox_client.h>
+
+#include "rpmsg_internal.h"
+#include "qcom_glink_native.h"
+
+#define RPM_TOC_SIZE		256
+#define RPM_TOC_MAGIC		0x67727430 /* grt0 */
+#define RPM_TOC_MAX_ENTRIES	((RPM_TOC_SIZE - sizeof(struct rpm_toc)) / \
+				 sizeof(struct rpm_toc_entry))
+
+#define RPM_TX_FIFO_ID		0x61703272 /* ap2r */
+#define RPM_RX_FIFO_ID		0x72326170 /* r2ap */
+
+#define to_rpm_pipe(p) container_of(p, struct glink_rpm_pipe, native)
+
+struct rpm_toc_entry {
+	__le32 id;
+	__le32 offset;
+	__le32 size;
+} __packed;
+
+struct rpm_toc {
+	__le32 magic;
+	__le32 count;
+
+	struct rpm_toc_entry entries[];
+} __packed;
+
+struct glink_rpm_pipe {
+	struct qcom_glink_pipe native;
+
+	void __iomem *tail;
+	void __iomem *head;
+
+	void __iomem *fifo;
+};
+
+struct glink_rpm {
+	struct qcom_glink *glink;
+
+	int irq;
+
+	struct mbox_client mbox_client;
+	struct mbox_chan *mbox_chan;
+
+	struct glink_rpm_pipe rx_pipe;
+	struct glink_rpm_pipe tx_pipe;
+};
+
+static size_t glink_rpm_rx_avail(struct qcom_glink_pipe *glink_pipe)
+{
+	struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe);
+	unsigned int head;
+	unsigned int tail;
+
+	head = readl(pipe->head);
+	tail = readl(pipe->tail);
+
+	if (head < tail)
+		return pipe->native.length - tail + head;
+	else
+		return head - tail;
+}
+
+static void glink_rpm_rx_peek(struct qcom_glink_pipe *glink_pipe,
+			      void *data, unsigned int offset, size_t count)
+{
+	struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe);
+	unsigned int tail;
+	size_t len;
+
+	tail = readl(pipe->tail);
+	tail += offset;
+	if (tail >= pipe->native.length)
+		tail -= pipe->native.length;
+
+	len = min_t(size_t, count, pipe->native.length - tail);
+	if (len) {
+		__ioread32_copy(data, pipe->fifo + tail,
+				len / sizeof(u32));
+	}
+
+	if (len != count) {
+		__ioread32_copy(data + len, pipe->fifo,
+				(count - len) / sizeof(u32));
+	}
+}
+
+static void glink_rpm_rx_advance(struct qcom_glink_pipe *glink_pipe,
+				 size_t count)
+{
+	struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe);
+	unsigned int tail;
+
+	tail = readl(pipe->tail);
+
+	tail += count;
+	if (tail >= pipe->native.length)
+		tail -= pipe->native.length;
+
+	writel(tail, pipe->tail);
+}
+
+static size_t glink_rpm_tx_avail(struct qcom_glink_pipe *glink_pipe)
+{
+	struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe);
+	unsigned int head;
+	unsigned int tail;
+
+	head = readl(pipe->head);
+	tail = readl(pipe->tail);
+
+	if (tail <= head)
+		return pipe->native.length - head + tail;
+	else
+		return tail - head;
+}
+
+static unsigned int glink_rpm_tx_write_one(struct glink_rpm_pipe *pipe,
+					   unsigned int head,
+					   const void *data, size_t count)
+{
+	size_t len;
+
+	len = min_t(size_t, count, pipe->native.length - head);
+	if (len) {
+		__iowrite32_copy(pipe->fifo + head, data,
+				 len / sizeof(u32));
+	}
+
+	if (len != count) {
+		__iowrite32_copy(pipe->fifo, data + len,
+				 (count - len) / sizeof(u32));
+	}
+
+	head += count;
+	if (head >= pipe->native.length)
+		head -= pipe->native.length;
+
+	return head;
+}
+
+static void glink_rpm_tx_write(struct qcom_glink_pipe *glink_pipe,
+			       const void *hdr, size_t hlen,
+			       const void *data, size_t dlen)
+{
+	struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe);
+	size_t tlen = hlen + dlen;
+	size_t aligned_dlen;
+	unsigned int head;
+	char padding[8] = {0};
+	size_t pad;
+
+	/* Header length comes from glink native and is always 4 byte aligned */
+	if (WARN(hlen % 4, "Glink Header length must be 4 bytes aligned\n"))
+		return;
+
+	/*
+	 * Move the unaligned tail of the message to the padding chunk, to
+	 * ensure word aligned accesses
+	 */
+	aligned_dlen = ALIGN_DOWN(dlen, 4);
+	if (aligned_dlen != dlen)
+		memcpy(padding, data + aligned_dlen, dlen - aligned_dlen);
+
+	head = readl(pipe->head);
+	head = glink_rpm_tx_write_one(pipe, head, hdr, hlen);
+	head = glink_rpm_tx_write_one(pipe, head, data, aligned_dlen);
+
+	pad = ALIGN(tlen, 8) - ALIGN_DOWN(tlen, 4);
+	if (pad)
+		head = glink_rpm_tx_write_one(pipe, head, padding, pad);
+	writel(head, pipe->head);
+}
+
+static void glink_rpm_tx_kick(struct qcom_glink_pipe *glink_pipe)
+{
+	struct glink_rpm_pipe *pipe = to_rpm_pipe(glink_pipe);
+	struct glink_rpm *rpm = container_of(pipe, struct glink_rpm, tx_pipe);
+
+	mbox_send_message(rpm->mbox_chan, NULL);
+	mbox_client_txdone(rpm->mbox_chan, 0);
+}
+
+static irqreturn_t qcom_glink_rpm_intr(int irq, void *data)
+{
+	struct glink_rpm *rpm = data;
+
+	qcom_glink_native_rx(rpm->glink);
+
+	return IRQ_HANDLED;
+}
+
+static int glink_rpm_parse_toc(struct device *dev,
+			       void __iomem *msg_ram,
+			       size_t msg_ram_size,
+			       struct glink_rpm_pipe *rx,
+			       struct glink_rpm_pipe *tx)
+{
+	struct rpm_toc *toc;
+	int num_entries;
+	unsigned int id;
+	size_t offset;
+	size_t size;
+	void *buf;
+	int i;
+
+	buf = kzalloc(RPM_TOC_SIZE, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	__ioread32_copy(buf, msg_ram + msg_ram_size - RPM_TOC_SIZE,
+			RPM_TOC_SIZE / sizeof(u32));
+
+	toc = buf;
+
+	if (le32_to_cpu(toc->magic) != RPM_TOC_MAGIC) {
+		dev_err(dev, "RPM TOC has invalid magic\n");
+		goto err_inval;
+	}
+
+	num_entries = le32_to_cpu(toc->count);
+	if (num_entries > RPM_TOC_MAX_ENTRIES) {
+		dev_err(dev, "Invalid number of toc entries\n");
+		goto err_inval;
+	}
+
+	for (i = 0; i < num_entries; i++) {
+		id = le32_to_cpu(toc->entries[i].id);
+		offset = le32_to_cpu(toc->entries[i].offset);
+		size = le32_to_cpu(toc->entries[i].size);
+
+		if (offset > msg_ram_size || offset + size > msg_ram_size) {
+			dev_err(dev, "TOC entry with invalid size\n");
+			continue;
+		}
+
+		switch (id) {
+		case RPM_RX_FIFO_ID:
+			rx->native.length = size;
+
+			rx->tail = msg_ram + offset;
+			rx->head = msg_ram + offset + sizeof(u32);
+			rx->fifo = msg_ram + offset + 2 * sizeof(u32);
+			break;
+		case RPM_TX_FIFO_ID:
+			tx->native.length = size;
+
+			tx->tail = msg_ram + offset;
+			tx->head = msg_ram + offset + sizeof(u32);
+			tx->fifo = msg_ram + offset + 2 * sizeof(u32);
+			break;
+		}
+	}
+
+	if (!rx->fifo || !tx->fifo) {
+		dev_err(dev, "Unable to find rx and tx descriptors\n");
+		goto err_inval;
+	}
+
+	kfree(buf);
+	return 0;
+
+err_inval:
+	kfree(buf);
+	return -EINVAL;
+}
+
+static int glink_rpm_probe(struct platform_device *pdev)
+{
+	struct qcom_glink *glink;
+	struct glink_rpm *rpm;
+	struct device_node *np;
+	void __iomem *msg_ram;
+	size_t msg_ram_size;
+	struct device *dev = &pdev->dev;
+	struct resource r;
+	int ret;
+
+	rpm = devm_kzalloc(&pdev->dev, sizeof(*rpm), GFP_KERNEL);
+	if (!rpm)
+		return -ENOMEM;
+
+	np = of_parse_phandle(dev->of_node, "qcom,rpm-msg-ram", 0);
+	ret = of_address_to_resource(np, 0, &r);
+	of_node_put(np);
+	if (ret)
+		return ret;
+
+	msg_ram = devm_ioremap(dev, r.start, resource_size(&r));
+	msg_ram_size = resource_size(&r);
+	if (!msg_ram)
+		return -ENOMEM;
+
+	ret = glink_rpm_parse_toc(dev, msg_ram, msg_ram_size,
+				  &rpm->rx_pipe, &rpm->tx_pipe);
+	if (ret)
+		return ret;
+
+	rpm->irq = of_irq_get(dev->of_node, 0);
+	ret = devm_request_irq(dev, rpm->irq, qcom_glink_rpm_intr,
+			       IRQF_NO_SUSPEND | IRQF_NO_AUTOEN,
+			       "glink-rpm", rpm);
+	if (ret) {
+		dev_err(dev, "failed to request IRQ\n");
+		return ret;
+	}
+
+	rpm->mbox_client.dev = dev;
+	rpm->mbox_client.knows_txdone = true;
+	rpm->mbox_chan = mbox_request_channel(&rpm->mbox_client, 0);
+	if (IS_ERR(rpm->mbox_chan))
+		return dev_err_probe(dev, PTR_ERR(rpm->mbox_chan), "failed to acquire IPC channel\n");
+
+	/* Pipe specific accessors */
+	rpm->rx_pipe.native.avail = glink_rpm_rx_avail;
+	rpm->rx_pipe.native.peek = glink_rpm_rx_peek;
+	rpm->rx_pipe.native.advance = glink_rpm_rx_advance;
+	rpm->tx_pipe.native.avail = glink_rpm_tx_avail;
+	rpm->tx_pipe.native.write = glink_rpm_tx_write;
+	rpm->tx_pipe.native.kick = glink_rpm_tx_kick;
+
+	writel(0, rpm->tx_pipe.head);
+	writel(0, rpm->rx_pipe.tail);
+
+	glink = qcom_glink_native_probe(dev,
+					0,
+					&rpm->rx_pipe.native,
+					&rpm->tx_pipe.native,
+					true);
+	if (IS_ERR(glink)) {
+		mbox_free_channel(rpm->mbox_chan);
+		return PTR_ERR(glink);
+	}
+
+	rpm->glink = glink;
+
+	platform_set_drvdata(pdev, rpm);
+
+	enable_irq(rpm->irq);
+
+	return 0;
+}
+
+static void glink_rpm_remove(struct platform_device *pdev)
+{
+	struct glink_rpm *rpm = platform_get_drvdata(pdev);
+	struct qcom_glink *glink = rpm->glink;
+
+	disable_irq(rpm->irq);
+
+	qcom_glink_native_remove(glink);
+
+	mbox_free_channel(rpm->mbox_chan);
+}
+
+static const struct of_device_id glink_rpm_of_match[] = {
+	{ .compatible = "qcom,glink-rpm" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, glink_rpm_of_match);
+
+static struct platform_driver glink_rpm_driver = {
+	.probe = glink_rpm_probe,
+	.remove = glink_rpm_remove,
+	.driver = {
+		.name = "qcom_glink_rpm",
+		.of_match_table = glink_rpm_of_match,
+	},
+};
+
+static int __init glink_rpm_init(void)
+{
+	return platform_driver_register(&glink_rpm_driver);
+}
+subsys_initcall(glink_rpm_init);
+
+static void __exit glink_rpm_exit(void)
+{
+	platform_driver_unregister(&glink_rpm_driver);
+}
+module_exit(glink_rpm_exit);
+
+MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@linaro.org>");
+MODULE_DESCRIPTION("Qualcomm GLINK RPM driver");
+MODULE_LICENSE("GPL v2");

linux-7.2.3/drivers/rpmsg/qcom_glink_smem.c

@@ -0,0 +1,378 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2016, Linaro Ltd
+ */
+
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/mailbox_client.h>
+#include <linux/mfd/syscon.h>
+#include <linux/slab.h>
+#include <linux/rpmsg.h>
+#include <linux/idr.h>
+#include <linux/circ_buf.h>
+#include <linux/soc/qcom/smem.h>
+#include <linux/sizes.h>
+#include <linux/delay.h>
+#include <linux/regmap.h>
+#include <linux/workqueue.h>
+#include <linux/list.h>
+
+#include <linux/rpmsg/qcom_glink.h>
+
+#include "qcom_glink_native.h"
+
+#define FIFO_FULL_RESERVE 8
+#define FIFO_ALIGNMENT 8
+#define TX_BLOCKED_CMD_RESERVE 8 /* size of struct read_notif_request */
+
+#define SMEM_GLINK_NATIVE_XPRT_DESCRIPTOR	478
+#define SMEM_GLINK_NATIVE_XPRT_FIFO_0		479
+#define SMEM_GLINK_NATIVE_XPRT_FIFO_1		480
+
+struct qcom_glink_smem {
+	struct device dev;
+
+	int irq;
+	struct qcom_glink *glink;
+
+	struct mbox_client mbox_client;
+	struct mbox_chan *mbox_chan;
+
+	u32 remote_pid;
+};
+
+struct glink_smem_pipe {
+	struct qcom_glink_pipe native;
+
+	__le32 *tail;
+	__le32 *head;
+
+	void *fifo;
+
+	struct qcom_glink_smem *smem;
+};
+
+#define to_smem_pipe(p) container_of(p, struct glink_smem_pipe, native)
+
+static size_t glink_smem_rx_avail(struct qcom_glink_pipe *np)
+{
+	struct glink_smem_pipe *pipe = to_smem_pipe(np);
+	struct qcom_glink_smem *smem = pipe->smem;
+	size_t len;
+	void *fifo;
+	u32 head;
+	u32 tail;
+
+	if (!pipe->fifo) {
+		fifo = qcom_smem_get(smem->remote_pid,
+				     SMEM_GLINK_NATIVE_XPRT_FIFO_1, &len);
+		if (IS_ERR(fifo)) {
+			pr_err("failed to acquire RX fifo handle: %ld\n",
+			       PTR_ERR(fifo));
+			return 0;
+		}
+
+		pipe->fifo = fifo;
+		pipe->native.length = len;
+	}
+
+	head = le32_to_cpu(*pipe->head);
+	tail = le32_to_cpu(*pipe->tail);
+
+	if (head < tail)
+		return pipe->native.length - tail + head;
+	else
+		return head - tail;
+}
+
+static void glink_smem_rx_peek(struct qcom_glink_pipe *np,
+			       void *data, unsigned int offset, size_t count)
+{
+	struct glink_smem_pipe *pipe = to_smem_pipe(np);
+	size_t len;
+	u32 tail;
+
+	tail = le32_to_cpu(*pipe->tail);
+	tail += offset;
+	if (tail >= pipe->native.length)
+		tail -= pipe->native.length;
+
+	len = min_t(size_t, count, pipe->native.length - tail);
+	if (len)
+		memcpy_fromio(data, pipe->fifo + tail, len);
+
+	if (len != count)
+		memcpy_fromio(data + len, pipe->fifo, (count - len));
+}
+
+static void glink_smem_rx_advance(struct qcom_glink_pipe *np,
+				  size_t count)
+{
+	struct glink_smem_pipe *pipe = to_smem_pipe(np);
+	u32 tail;
+
+	tail = le32_to_cpu(*pipe->tail);
+
+	tail += count;
+	if (tail >= pipe->native.length)
+		tail -= pipe->native.length;
+
+	*pipe->tail = cpu_to_le32(tail);
+}
+
+static size_t glink_smem_tx_avail(struct qcom_glink_pipe *np)
+{
+	struct glink_smem_pipe *pipe = to_smem_pipe(np);
+	u32 head;
+	u32 tail;
+	u32 avail;
+
+	head = le32_to_cpu(*pipe->head);
+	tail = le32_to_cpu(*pipe->tail);
+
+	if (tail <= head)
+		avail = pipe->native.length - head + tail;
+	else
+		avail = tail - head;
+
+	if (avail < (FIFO_FULL_RESERVE + TX_BLOCKED_CMD_RESERVE))
+		avail = 0;
+	else
+		avail -= FIFO_FULL_RESERVE + TX_BLOCKED_CMD_RESERVE;
+
+	return avail;
+}
+
+static unsigned int glink_smem_tx_write_one(struct glink_smem_pipe *pipe,
+					    unsigned int head,
+					    const void *data, size_t count)
+{
+	size_t len;
+
+	len = min_t(size_t, count, pipe->native.length - head);
+	if (len)
+		memcpy(pipe->fifo + head, data, len);
+
+	if (len != count)
+		memcpy(pipe->fifo, data + len, count - len);
+
+	head += count;
+	if (head >= pipe->native.length)
+		head -= pipe->native.length;
+
+	return head;
+}
+
+static void glink_smem_tx_write(struct qcom_glink_pipe *glink_pipe,
+				const void *hdr, size_t hlen,
+				const void *data, size_t dlen)
+{
+	struct glink_smem_pipe *pipe = to_smem_pipe(glink_pipe);
+	unsigned int head;
+
+	head = le32_to_cpu(*pipe->head);
+
+	head = glink_smem_tx_write_one(pipe, head, hdr, hlen);
+	head = glink_smem_tx_write_one(pipe, head, data, dlen);
+
+	/* Ensure head is always aligned to 8 bytes */
+	head = ALIGN(head, 8);
+	if (head >= pipe->native.length)
+		head -= pipe->native.length;
+
+	/* Ensure ordering of fifo and head update */
+	wmb();
+
+	*pipe->head = cpu_to_le32(head);
+}
+
+static void glink_smem_tx_kick(struct qcom_glink_pipe *glink_pipe)
+{
+	struct glink_smem_pipe *pipe = to_smem_pipe(glink_pipe);
+	struct qcom_glink_smem *smem = pipe->smem;
+
+	mbox_send_message(smem->mbox_chan, NULL);
+	mbox_client_txdone(smem->mbox_chan, 0);
+}
+
+static irqreturn_t qcom_glink_smem_intr(int irq, void *data)
+{
+	struct qcom_glink_smem *smem = data;
+
+	qcom_glink_native_rx(smem->glink);
+
+	return IRQ_HANDLED;
+}
+
+static void qcom_glink_smem_release(struct device *dev)
+{
+	struct qcom_glink_smem *smem = container_of(dev, struct qcom_glink_smem, dev);
+
+	kfree(smem);
+}
+
+struct qcom_glink_smem *qcom_glink_smem_register(struct device *parent,
+						 struct device_node *node)
+{
+	struct glink_smem_pipe *rx_pipe;
+	struct glink_smem_pipe *tx_pipe;
+	struct qcom_glink_smem *smem;
+	struct qcom_glink *glink;
+	struct device *dev;
+	u32 remote_pid;
+	__le32 *descs;
+	size_t size;
+	int ret;
+
+	smem = kzalloc_obj(*smem);
+	if (!smem)
+		return ERR_PTR(-ENOMEM);
+
+	dev = &smem->dev;
+
+	dev->parent = parent;
+	dev->of_node = node;
+	dev->release = qcom_glink_smem_release;
+	dev_set_name(dev, "%s:%pOFn", dev_name(parent->parent), node);
+	ret = device_register(dev);
+	if (ret) {
+		pr_err("failed to register glink edge\n");
+		put_device(dev);
+		return ERR_PTR(ret);
+	}
+
+	ret = of_property_read_u32(dev->of_node, "qcom,remote-pid",
+				   &remote_pid);
+	if (ret) {
+		dev_err(dev, "failed to parse qcom,remote-pid\n");
+		goto err_put_dev;
+	}
+
+	smem->remote_pid = remote_pid;
+
+	rx_pipe = devm_kzalloc(dev, sizeof(*rx_pipe), GFP_KERNEL);
+	tx_pipe = devm_kzalloc(dev, sizeof(*tx_pipe), GFP_KERNEL);
+	if (!rx_pipe || !tx_pipe) {
+		ret = -ENOMEM;
+		goto err_put_dev;
+	}
+
+	ret = qcom_smem_alloc(remote_pid,
+			      SMEM_GLINK_NATIVE_XPRT_DESCRIPTOR, 32);
+	if (ret && ret != -EEXIST) {
+		dev_err(dev, "failed to allocate glink descriptors\n");
+		goto err_put_dev;
+	}
+
+	descs = qcom_smem_get(remote_pid,
+			      SMEM_GLINK_NATIVE_XPRT_DESCRIPTOR, &size);
+	if (IS_ERR(descs)) {
+		dev_err(dev, "failed to acquire xprt descriptor\n");
+		ret = PTR_ERR(descs);
+		goto err_put_dev;
+	}
+
+	if (size != 32) {
+		dev_err(dev, "glink descriptor of invalid size\n");
+		ret = -EINVAL;
+		goto err_put_dev;
+	}
+
+	tx_pipe->tail = &descs[0];
+	tx_pipe->head = &descs[1];
+	rx_pipe->tail = &descs[2];
+	rx_pipe->head = &descs[3];
+
+	ret = qcom_smem_alloc(remote_pid, SMEM_GLINK_NATIVE_XPRT_FIFO_0,
+			      SZ_16K);
+	if (ret && ret != -EEXIST) {
+		dev_err(dev, "failed to allocate TX fifo\n");
+		goto err_put_dev;
+	}
+
+	tx_pipe->fifo = qcom_smem_get(remote_pid, SMEM_GLINK_NATIVE_XPRT_FIFO_0,
+				      &tx_pipe->native.length);
+	if (IS_ERR(tx_pipe->fifo)) {
+		dev_err(dev, "failed to acquire TX fifo\n");
+		ret = PTR_ERR(tx_pipe->fifo);
+		goto err_put_dev;
+	}
+
+	smem->irq = of_irq_get(smem->dev.of_node, 0);
+	ret = devm_request_irq(&smem->dev, smem->irq, qcom_glink_smem_intr,
+			       IRQF_NO_SUSPEND | IRQF_NO_AUTOEN,
+			       "glink-smem", smem);
+	if (ret) {
+		dev_err(&smem->dev, "failed to request IRQ\n");
+		goto err_put_dev;
+	}
+
+	smem->mbox_client.dev = &smem->dev;
+	smem->mbox_client.knows_txdone = true;
+	smem->mbox_chan = mbox_request_channel(&smem->mbox_client, 0);
+	if (IS_ERR(smem->mbox_chan)) {
+		ret = dev_err_probe(&smem->dev, PTR_ERR(smem->mbox_chan),
+				    "failed to acquire IPC channel\n");
+		goto err_put_dev;
+	}
+
+	rx_pipe->smem = smem;
+	rx_pipe->native.avail = glink_smem_rx_avail;
+	rx_pipe->native.peek = glink_smem_rx_peek;
+	rx_pipe->native.advance = glink_smem_rx_advance;
+
+	tx_pipe->smem = smem;
+	tx_pipe->native.avail = glink_smem_tx_avail;
+	tx_pipe->native.write = glink_smem_tx_write;
+	tx_pipe->native.kick = glink_smem_tx_kick;
+
+	*rx_pipe->tail = 0;
+	*tx_pipe->head = 0;
+
+	glink = qcom_glink_native_probe(dev,
+					GLINK_FEATURE_INTENT_REUSE,
+					&rx_pipe->native, &tx_pipe->native,
+					false);
+	if (IS_ERR(glink)) {
+		ret = PTR_ERR(glink);
+		goto err_free_mbox;
+	}
+
+	smem->glink = glink;
+
+	enable_irq(smem->irq);
+
+	return smem;
+
+err_free_mbox:
+	mbox_free_channel(smem->mbox_chan);
+
+err_put_dev:
+	device_unregister(dev);
+
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(qcom_glink_smem_register);
+
+void qcom_glink_smem_unregister(struct qcom_glink_smem *smem)
+{
+	struct qcom_glink *glink = smem->glink;
+
+	disable_irq(smem->irq);
+
+	qcom_glink_native_remove(glink);
+
+	mbox_free_channel(smem->mbox_chan);
+	device_unregister(&smem->dev);
+}
+EXPORT_SYMBOL_GPL(qcom_glink_smem_unregister);
+
+MODULE_AUTHOR("Bjorn Andersson <bjorn.andersson@linaro.org>");
+MODULE_DESCRIPTION("Qualcomm GLINK SMEM driver");
+MODULE_LICENSE("GPL v2");

linux-7.2.3/drivers/rpmsg/qcom_glink_ssr.c

@@ -0,0 +1,168 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2014-2017, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2017, Linaro Ltd.
+ */
+
+#include <linux/completion.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/rpmsg.h>
+#include <linux/rpmsg/qcom_glink.h>
+#include <linux/remoteproc/qcom_rproc.h>
+
+/**
+ * struct do_cleanup_msg - The data structure for an SSR do_cleanup message
+ * @version:	The G-Link SSR protocol version
+ * @command:	The G-Link SSR command - do_cleanup
+ * @seq_num:	Sequence number
+ * @name_len:	Length of the name of the subsystem being restarted
+ * @name:	G-Link edge name of the subsystem being restarted
+ */
+struct do_cleanup_msg {
+	__le32 version;
+	__le32 command;
+	__le32 seq_num;
+	__le32 name_len;
+	char name[32];
+};
+
+/**
+ * struct cleanup_done_msg - The data structure for an SSR cleanup_done message
+ * @version:	The G-Link SSR protocol version
+ * @response:	The G-Link SSR response to a do_cleanup command, cleanup_done
+ * @seq_num:	Sequence number
+ */
+struct cleanup_done_msg {
+	__le32 version;
+	__le32 response;
+	__le32 seq_num;
+};
+
+/*
+ * G-Link SSR protocol commands
+ */
+#define GLINK_SSR_DO_CLEANUP	0
+#define GLINK_SSR_CLEANUP_DONE	1
+
+struct glink_ssr {
+	struct device *dev;
+	struct rpmsg_endpoint *ept;
+
+	struct notifier_block nb;
+
+	u32 seq_num;
+	struct completion completion;
+};
+
+/* Notifier list for all registered glink_ssr instances */
+static BLOCKING_NOTIFIER_HEAD(ssr_notifiers);
+
+/**
+ * qcom_glink_ssr_notify() - notify GLINK SSR about stopped remoteproc
+ * @ssr_name:	name of the remoteproc that has been stopped
+ */
+void qcom_glink_ssr_notify(const char *ssr_name)
+{
+	blocking_notifier_call_chain(&ssr_notifiers, 0, (void *)ssr_name);
+}
+EXPORT_SYMBOL_GPL(qcom_glink_ssr_notify);
+
+static int qcom_glink_ssr_callback(struct rpmsg_device *rpdev,
+				   void *data, int len, void *priv, u32 addr)
+{
+	struct cleanup_done_msg *msg = data;
+	struct glink_ssr *ssr = dev_get_drvdata(&rpdev->dev);
+
+	if (len < sizeof(*msg)) {
+		dev_err(ssr->dev, "message too short\n");
+		return -EINVAL;
+	}
+
+	if (le32_to_cpu(msg->version) != 0)
+		return -EINVAL;
+
+	if (le32_to_cpu(msg->response) != GLINK_SSR_CLEANUP_DONE)
+		return 0;
+
+	if (le32_to_cpu(msg->seq_num) != ssr->seq_num) {
+		dev_err(ssr->dev, "invalid sequence number of response\n");
+		return -EINVAL;
+	}
+
+	complete(&ssr->completion);
+
+	return 0;
+}
+
+static int qcom_glink_ssr_notifier_call(struct notifier_block *nb,
+					unsigned long event,
+					void *data)
+{
+	struct glink_ssr *ssr = container_of(nb, struct glink_ssr, nb);
+	struct do_cleanup_msg msg;
+	char *ssr_name = data;
+	int ret;
+
+	ssr->seq_num++;
+	reinit_completion(&ssr->completion);
+
+	memset(&msg, 0, sizeof(msg));
+	msg.command = cpu_to_le32(GLINK_SSR_DO_CLEANUP);
+	msg.seq_num = cpu_to_le32(ssr->seq_num);
+	msg.name_len = cpu_to_le32(strlen(ssr_name));
+	strscpy(msg.name, ssr_name, sizeof(msg.name));
+
+	ret = rpmsg_send(ssr->ept, &msg, sizeof(msg));
+	if (ret < 0)
+		dev_err(ssr->dev, "failed to send cleanup message\n");
+
+	ret = wait_for_completion_timeout(&ssr->completion, HZ);
+	if (!ret)
+		dev_err(ssr->dev, "timeout waiting for cleanup done message\n");
+
+	return NOTIFY_DONE;
+}
+
+static int qcom_glink_ssr_probe(struct rpmsg_device *rpdev)
+{
+	struct glink_ssr *ssr;
+
+	ssr = devm_kzalloc(&rpdev->dev, sizeof(*ssr), GFP_KERNEL);
+	if (!ssr)
+		return -ENOMEM;
+
+	init_completion(&ssr->completion);
+
+	ssr->dev = &rpdev->dev;
+	ssr->ept = rpdev->ept;
+	ssr->nb.notifier_call = qcom_glink_ssr_notifier_call;
+
+	dev_set_drvdata(&rpdev->dev, ssr);
+
+	return blocking_notifier_chain_register(&ssr_notifiers, &ssr->nb);
+}
+
+static void qcom_glink_ssr_remove(struct rpmsg_device *rpdev)
+{
+	struct glink_ssr *ssr = dev_get_drvdata(&rpdev->dev);
+
+	blocking_notifier_chain_unregister(&ssr_notifiers, &ssr->nb);
+}
+
+static const struct rpmsg_device_id qcom_glink_ssr_match[] = {
+	{ "glink_ssr" },
+	{}
+};
+MODULE_DEVICE_TABLE(rpmsg, qcom_glink_ssr_match);
+
+static struct rpmsg_driver qcom_glink_ssr_driver = {
+	.probe = qcom_glink_ssr_probe,
+	.remove = qcom_glink_ssr_remove,
+	.callback = qcom_glink_ssr_callback,
+	.id_table = qcom_glink_ssr_match,
+	.drv = {
+		.name = "qcom_glink_ssr",
+	},
+};
+module_rpmsg_driver(qcom_glink_ssr_driver);

linux-7.2.3/drivers/rpmsg/qcom_glink_trace.h

@@ -0,0 +1,406 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM qcom_glink
+
+#if !defined(__QCOM_GLINK_TRACE_H__) || defined(TRACE_HEADER_MULTI_READ)
+#define __QCOM_GLINK_TRACE_H__
+
+#include <linux/tracepoint.h>
+#include "qcom_glink_native.h"
+
+
+TRACE_EVENT(qcom_glink_cmd_version,
+	TP_PROTO(const char *remote, unsigned int version, unsigned int features, bool tx),
+	TP_ARGS(remote, version, features, tx),
+	TP_STRUCT__entry(
+		__string(remote, remote)
+		__field(u32, version)
+		__field(u32, features)
+		__field(bool, tx)
+	),
+	TP_fast_assign(
+		__assign_str(remote);
+		__entry->version = version;
+		__entry->features = features;
+		__entry->tx = tx;
+	),
+	TP_printk("%s remote: %s version: %u features: %#x",
+		  __entry->tx ? "tx" : "rx",
+		  __get_str(remote),
+		  __entry->version,
+		  __entry->features
+	)
+);
+#define trace_qcom_glink_cmd_version_tx(...) trace_qcom_glink_cmd_version(__VA_ARGS__, true)
+#define trace_qcom_glink_cmd_version_rx(...) trace_qcom_glink_cmd_version(__VA_ARGS__, false)
+
+TRACE_EVENT(qcom_glink_cmd_version_ack,
+	TP_PROTO(const char *remote, unsigned int version, unsigned int features, bool tx),
+	TP_ARGS(remote, version, features, tx),
+	TP_STRUCT__entry(
+		__string(remote, remote)
+		__field(u32, version)
+		__field(u32, features)
+		__field(bool, tx)
+	),
+	TP_fast_assign(
+		__assign_str(remote);
+		__entry->version = version;
+		__entry->features = features;
+		__entry->tx = tx;
+	),
+	TP_printk("%s remote: %s version: %u features: %#x",
+		  __entry->tx ? "tx" : "rx",
+		  __get_str(remote),
+		  __entry->version,
+		  __entry->features
+	)
+);
+#define trace_qcom_glink_cmd_version_ack_tx(...) trace_qcom_glink_cmd_version_ack(__VA_ARGS__, true)
+#define trace_qcom_glink_cmd_version_ack_rx(...) trace_qcom_glink_cmd_version_ack(__VA_ARGS__, false)
+
+TRACE_EVENT(qcom_glink_cmd_open,
+	TP_PROTO(const char *remote, const char *channel, u16 lcid, u16 rcid, bool tx),
+	TP_ARGS(remote, channel, lcid, rcid, tx),
+	TP_STRUCT__entry(
+		__string(remote, remote)
+		__string(channel, channel)
+		__field(u16, lcid)
+		__field(u16, rcid)
+		__field(bool, tx)
+	),
+	TP_fast_assign(
+		__assign_str(remote);
+		__assign_str(channel);
+		__entry->lcid = lcid;
+		__entry->rcid = rcid;
+		__entry->tx = tx;
+	),
+	TP_printk("%s remote: %s channel: %s[%u/%u]",
+		  __entry->tx ? "tx" : "rx",
+		  __get_str(remote),
+		  __get_str(channel),
+		  __entry->lcid,
+		  __entry->rcid
+	)
+);
+#define trace_qcom_glink_cmd_open_tx(...) trace_qcom_glink_cmd_open(__VA_ARGS__, true)
+#define trace_qcom_glink_cmd_open_rx(...) trace_qcom_glink_cmd_open(__VA_ARGS__, false)
+
+TRACE_EVENT(qcom_glink_cmd_close,
+	TP_PROTO(const char *remote, const char *channel, u16 lcid, u16 rcid, bool tx),
+	TP_ARGS(remote, channel, lcid, rcid, tx),
+	TP_STRUCT__entry(
+		__string(remote, remote)
+		__string(channel, channel)
+		__field(u16, lcid)
+		__field(u16, rcid)
+		__field(bool, tx)
+	),
+	TP_fast_assign(
+		__assign_str(remote);
+		__assign_str(channel);
+		__entry->lcid = lcid;
+		__entry->rcid = rcid;
+		__entry->tx = tx;
+	),
+	TP_printk("%s remote: %s channel: %s[%u/%u]",
+		  __entry->tx ? "tx" : "rx",
+		  __get_str(remote),
+		  __get_str(channel),
+		  __entry->lcid,
+		  __entry->rcid
+	)
+);
+#define trace_qcom_glink_cmd_close_tx(...) trace_qcom_glink_cmd_close(__VA_ARGS__, true)
+#define trace_qcom_glink_cmd_close_rx(...) trace_qcom_glink_cmd_close(__VA_ARGS__, false)
+
+TRACE_EVENT(qcom_glink_cmd_open_ack,
+	TP_PROTO(const char *remote, const char *channel, u16 lcid, u16 rcid, bool tx),
+	TP_ARGS(remote, channel, lcid, rcid, tx),
+	TP_STRUCT__entry(
+		__string(remote, remote)
+		__string(channel, channel)
+		__field(u16, lcid)
+		__field(u16, rcid)
+		__field(bool, tx)
+	),
+	TP_fast_assign(
+		__assign_str(remote);
+		__assign_str(channel);
+		__entry->lcid = lcid;
+		__entry->rcid = rcid;
+		__entry->tx = tx;
+	),
+	TP_printk("%s remote: %s channel: %s[%u/%u]",
+		  __entry->tx ? "tx" : "rx",
+		  __get_str(remote),
+		  __get_str(channel),
+		  __entry->lcid,
+		  __entry->rcid
+	)
+);
+#define trace_qcom_glink_cmd_open_ack_tx(...) trace_qcom_glink_cmd_open_ack(__VA_ARGS__, true)
+#define trace_qcom_glink_cmd_open_ack_rx(...) trace_qcom_glink_cmd_open_ack(__VA_ARGS__, false)
+
+TRACE_EVENT(qcom_glink_cmd_intent,
+	TP_PROTO(const char *remote, const char *channel, u16 lcid, u16 rcid, size_t count, size_t size, u32 liid, bool tx),
+	TP_ARGS(remote, channel, lcid, rcid, count, size, liid, tx),
+	TP_STRUCT__entry(
+		__string(remote, remote)
+		__string(channel, channel)
+		__field(u16, lcid)
+		__field(u16, rcid)
+		__field(u32, count)
+		__field(u32, size)
+		__field(u32, liid)
+		__field(bool, tx)
+	),
+	TP_fast_assign(
+		__assign_str(remote);
+		__assign_str(channel);
+		__entry->lcid = lcid;
+		__entry->rcid = rcid;
+		__entry->count = count;
+		__entry->size = size;
+		__entry->liid = liid;
+		__entry->tx = tx;
+	),
+	TP_printk("%s remote: %s channel: %s[%u/%u] count: %d [size: %d liid: %d]",
+		  __entry->tx ? "tx" : "rx",
+		  __get_str(remote),
+		  __get_str(channel),
+		  __entry->lcid,
+		  __entry->rcid,
+		  __entry->count,
+		  __entry->size,
+		  __entry->liid
+	)
+);
+#define trace_qcom_glink_cmd_intent_tx(...) trace_qcom_glink_cmd_intent(__VA_ARGS__, true)
+#define trace_qcom_glink_cmd_intent_rx(...) trace_qcom_glink_cmd_intent(__VA_ARGS__, false)
+
+TRACE_EVENT(qcom_glink_cmd_rx_done,
+	TP_PROTO(const char *remote, const char *channel, u16 lcid, u16 rcid, u32 iid, bool reuse, bool tx),
+	TP_ARGS(remote, channel, lcid, rcid, iid, reuse, tx),
+	TP_STRUCT__entry(
+		__string(remote, remote)
+		__string(channel, channel)
+		__field(u16, lcid)
+		__field(u16, rcid)
+		__field(u32, iid)
+		__field(bool, reuse)
+		__field(bool, tx)
+	),
+	TP_fast_assign(
+		__assign_str(remote);
+		__assign_str(channel);
+		__entry->lcid = lcid;
+		__entry->rcid = rcid;
+		__entry->iid = iid;
+		__entry->reuse = reuse;
+		__entry->tx = tx;
+	),
+	TP_printk("%s remote: %s channel: %s[%u/%u] iid: %d reuse: %d",
+		  __entry->tx ? "tx" : "rx",
+		  __get_str(remote),
+		  __get_str(channel),
+		  __entry->lcid,
+		  __entry->rcid,
+		  __entry->iid,
+		  __entry->reuse
+	)
+);
+#define trace_qcom_glink_cmd_rx_done_tx(...) trace_qcom_glink_cmd_rx_done(__VA_ARGS__, true)
+#define trace_qcom_glink_cmd_rx_done_rx(...) trace_qcom_glink_cmd_rx_done(__VA_ARGS__, false)
+
+TRACE_EVENT(qcom_glink_cmd_rx_intent_req,
+	TP_PROTO(const char *remote, const char *channel, u16 lcid, u16 rcid, size_t size, bool tx),
+	TP_ARGS(remote, channel, lcid, rcid, size, tx),
+	TP_STRUCT__entry(
+		__string(remote, remote)
+		__string(channel, channel)
+		__field(u16, lcid)
+		__field(u16, rcid)
+		__field(u32, size)
+		__field(bool, tx)
+	),
+	TP_fast_assign(
+		__assign_str(remote);
+		__assign_str(channel);
+		__entry->lcid = lcid;
+		__entry->rcid = rcid;
+		__entry->size = size;
+		__entry->tx = tx;
+	),
+	TP_printk("%s remote: %s channel: %s[%u/%u] size: %d",
+		  __entry->tx ? "tx" : "rx",
+		  __get_str(remote),
+		  __get_str(channel),
+		  __entry->lcid,
+		  __entry->rcid,
+		  __entry->size
+	)
+);
+#define trace_qcom_glink_cmd_rx_intent_req_tx(...) trace_qcom_glink_cmd_rx_intent_req(__VA_ARGS__, true)
+#define trace_qcom_glink_cmd_rx_intent_req_rx(...) trace_qcom_glink_cmd_rx_intent_req(__VA_ARGS__, false)
+
+TRACE_EVENT(qcom_glink_cmd_rx_intent_req_ack,
+	TP_PROTO(const char *remote, const char *channel, u16 lcid, u16 rcid, bool granted, bool tx),
+	TP_ARGS(remote, channel, lcid, rcid, granted, tx),
+	TP_STRUCT__entry(
+		__string(remote, remote)
+		__string(channel, channel)
+		__field(u16, lcid)
+		__field(u16, rcid)
+		__field(bool, granted)
+		__field(bool, tx)
+	),
+	TP_fast_assign(
+		__assign_str(remote);
+		__assign_str(channel);
+		__entry->lcid = lcid;
+		__entry->rcid = rcid;
+		__entry->granted = granted;
+		__entry->tx = tx;
+	),
+	TP_printk("%s remote: %s channel: %s[%u/%u] granted: %d",
+		  __entry->tx ? "tx" : "rx",
+		  __get_str(remote),
+		  __get_str(channel),
+		  __entry->lcid,
+		  __entry->rcid,
+		  __entry->granted
+	)
+);
+#define trace_qcom_glink_cmd_rx_intent_req_ack_tx(...) trace_qcom_glink_cmd_rx_intent_req_ack(__VA_ARGS__, true)
+#define trace_qcom_glink_cmd_rx_intent_req_ack_rx(...) trace_qcom_glink_cmd_rx_intent_req_ack(__VA_ARGS__, false)
+
+TRACE_EVENT(qcom_glink_cmd_tx_data,
+	TP_PROTO(const char *remote, const char *channel, u16 lcid, u16 rcid, u32 iid, u32 chunk_size, u32 left_size, bool cont, bool tx),
+	TP_ARGS(remote, channel, lcid, rcid, iid, chunk_size, left_size, cont, tx),
+	TP_STRUCT__entry(
+		__string(remote, remote)
+		__string(channel, channel)
+		__field(u16, lcid)
+		__field(u16, rcid)
+		__field(u32, iid)
+		__field(u32, chunk_size)
+		__field(u32, left_size)
+		__field(bool, cont)
+		__field(bool, tx)
+	),
+	TP_fast_assign(
+		__assign_str(remote);
+		__assign_str(channel);
+		__entry->lcid = lcid;
+		__entry->rcid = rcid;
+		__entry->iid = iid;
+		__entry->chunk_size = chunk_size;
+		__entry->left_size = left_size;
+		__entry->cont = cont;
+		__entry->tx = tx;
+	),
+	TP_printk("%s remote: %s channel: %s[%u/%u] iid: %d chunk_size: %d left_size: %d cont: %d",
+		  __entry->tx ? "tx" : "rx",
+		  __get_str(remote),
+		  __get_str(channel),
+		  __entry->lcid,
+		  __entry->rcid,
+		  __entry->iid,
+		  __entry->chunk_size,
+		  __entry->left_size,
+		  __entry->cont
+	)
+);
+#define trace_qcom_glink_cmd_tx_data_tx(...) trace_qcom_glink_cmd_tx_data(__VA_ARGS__, true)
+#define trace_qcom_glink_cmd_tx_data_rx(...) trace_qcom_glink_cmd_tx_data(__VA_ARGS__, false)
+
+TRACE_EVENT(qcom_glink_cmd_close_ack,
+	TP_PROTO(const char *remote, const char *channel, u16 lcid, u16 rcid, bool tx),
+	TP_ARGS(remote, channel, lcid, rcid, tx),
+	TP_STRUCT__entry(
+		__string(remote, remote)
+		__string(channel, channel)
+		__field(u16, lcid)
+		__field(u16, rcid)
+		__field(bool, tx)
+	),
+	TP_fast_assign(
+		__assign_str(remote);
+		__assign_str(channel);
+		__entry->lcid = lcid;
+		__entry->rcid = rcid;
+		__entry->tx = tx;
+	),
+	TP_printk("%s remote: %s channel: %s[%u/%u]",
+		  __entry->tx ? "tx" : "rx",
+		  __get_str(remote),
+		  __get_str(channel),
+		  __entry->lcid,
+		  __entry->rcid
+	)
+);
+#define trace_qcom_glink_cmd_close_ack_tx(...) trace_qcom_glink_cmd_close_ack(__VA_ARGS__, true)
+#define trace_qcom_glink_cmd_close_ack_rx(...) trace_qcom_glink_cmd_close_ack(__VA_ARGS__, false)
+
+TRACE_EVENT(qcom_glink_cmd_read_notif,
+	TP_PROTO(const char *remote, bool tx),
+	TP_ARGS(remote, tx),
+	TP_STRUCT__entry(
+		__string(remote, remote)
+		__field(bool, tx)
+	),
+	TP_fast_assign(
+		__assign_str(remote);
+		__entry->tx = tx;
+	),
+	TP_printk("%s remote: %s",
+		  __entry->tx ? "tx" : "rx",
+		  __get_str(remote)
+	)
+);
+#define trace_qcom_glink_cmd_read_notif_tx(...) trace_qcom_glink_cmd_read_notif(__VA_ARGS__, true)
+#define trace_qcom_glink_cmd_read_notif_rx(...) trace_qcom_glink_cmd_read_notif(__VA_ARGS__, false)
+
+TRACE_EVENT(qcom_glink_cmd_signal,
+	TP_PROTO(const char *remote, const char *channel, u16 lcid, u16 rcid, unsigned int signals, bool tx),
+	TP_ARGS(remote, channel, lcid, rcid, signals, tx),
+	TP_STRUCT__entry(
+		__string(remote, remote)
+		__string(channel, channel)
+		__field(u16, lcid)
+		__field(u16, rcid)
+		__field(u32, signals)
+		__field(bool, tx)
+	),
+	TP_fast_assign(
+		__assign_str(remote);
+		__assign_str(channel);
+		__entry->lcid = lcid;
+		__entry->rcid = rcid;
+		__entry->signals = signals;
+		__entry->tx = tx;
+	),
+	TP_printk("%s remote: %s channel: %s[%u/%u] signals: %#x",
+		  __entry->tx ? "tx" : "rx",
+		  __get_str(remote),
+		  __get_str(channel),
+		  __entry->lcid,
+		  __entry->rcid,
+		  __entry->signals
+	)
+);
+#define trace_qcom_glink_cmd_signal_tx(...) trace_qcom_glink_cmd_signal(__VA_ARGS__, true)
+#define trace_qcom_glink_cmd_signal_rx(...) trace_qcom_glink_cmd_signal(__VA_ARGS__, false)
+
+#endif
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE qcom_glink_trace
+
+#include <trace/define_trace.h>

linux-7.2.3/drivers/rpmsg/rpmsg_char.c

@@ -0,0 +1,582 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022, STMicroelectronics
+ * Copyright (c) 2016, Linaro Ltd.
+ * Copyright (c) 2012, Michal Simek <monstr@monstr.eu>
+ * Copyright (c) 2012, PetaLogix
+ * Copyright (c) 2011, Texas Instruments, Inc.
+ * Copyright (c) 2011, Google, Inc.
+ *
+ * Based on rpmsg performance statistics driver by Michal Simek, which in turn
+ * was based on TI & Google OMX rpmsg driver.
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/idr.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/poll.h>
+#include <linux/rpmsg.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <uapi/linux/rpmsg.h>
+
+#include "rpmsg_char.h"
+#include "rpmsg_internal.h"
+
+#define RPMSG_DEV_MAX	(MINORMASK + 1)
+
+static dev_t rpmsg_major;
+
+static DEFINE_IDA(rpmsg_ept_ida);
+static DEFINE_IDA(rpmsg_minor_ida);
+
+#define dev_to_eptdev(dev) container_of(dev, struct rpmsg_eptdev, dev)
+#define cdev_to_eptdev(i_cdev) container_of(i_cdev, struct rpmsg_eptdev, cdev)
+
+/**
+ * struct rpmsg_eptdev - endpoint device context
+ * @dev:	endpoint device
+ * @cdev:	cdev for the endpoint device
+ * @rpdev:	underlaying rpmsg device
+ * @chinfo:	info used to open the endpoint
+ * @ept_lock:	synchronization of @ept modifications
+ * @ept:	rpmsg endpoint reference, when open
+ * @queue_lock:	synchronization of @queue operations
+ * @queue:	incoming message queue
+ * @readq:	wait object for incoming queue
+ * @default_ept: set to channel default endpoint if the default endpoint should be re-used
+ *              on device open to prevent endpoint address update.
+ * @remote_flow_restricted: to indicate if the remote has requested for flow to be limited
+ * @remote_flow_updated: to indicate if the flow control has been requested
+ */
+struct rpmsg_eptdev {
+	struct device dev;
+	struct cdev cdev;
+
+	struct rpmsg_device *rpdev;
+	struct rpmsg_channel_info chinfo;
+
+	struct mutex ept_lock;
+	struct rpmsg_endpoint *ept;
+	struct rpmsg_endpoint *default_ept;
+
+	spinlock_t queue_lock;
+	struct sk_buff_head queue;
+	wait_queue_head_t readq;
+
+	bool remote_flow_restricted;
+	bool remote_flow_updated;
+};
+
+int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data)
+{
+	struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev);
+
+	mutex_lock(&eptdev->ept_lock);
+	eptdev->rpdev = NULL;
+	if (eptdev->ept) {
+		/* The default endpoint is released by the rpmsg core */
+		if (!eptdev->default_ept)
+			rpmsg_destroy_ept(eptdev->ept);
+		eptdev->ept = NULL;
+	}
+	mutex_unlock(&eptdev->ept_lock);
+
+	/* wake up any blocked readers */
+	wake_up_interruptible(&eptdev->readq);
+
+	cdev_device_del(&eptdev->cdev, &eptdev->dev);
+	put_device(&eptdev->dev);
+
+	return 0;
+}
+EXPORT_SYMBOL(rpmsg_chrdev_eptdev_destroy);
+
+static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len,
+			void *priv, u32 addr)
+{
+	struct rpmsg_eptdev *eptdev = priv;
+	struct sk_buff *skb;
+
+	if (!eptdev)
+		return 0;
+
+	skb = alloc_skb(len, GFP_ATOMIC);
+	if (!skb)
+		return -ENOMEM;
+
+	skb_put_data(skb, buf, len);
+
+	spin_lock(&eptdev->queue_lock);
+	skb_queue_tail(&eptdev->queue, skb);
+	spin_unlock(&eptdev->queue_lock);
+
+	/* wake up any blocking processes, waiting for new data */
+	wake_up_interruptible(&eptdev->readq);
+
+	return 0;
+}
+
+static int rpmsg_ept_flow_cb(struct rpmsg_device *rpdev, void *priv, bool enable)
+{
+	struct rpmsg_eptdev *eptdev = priv;
+
+	if (!eptdev)
+		return 0;
+
+	eptdev->remote_flow_restricted = enable;
+	eptdev->remote_flow_updated = true;
+
+	wake_up_interruptible(&eptdev->readq);
+
+	return 0;
+}
+
+static int rpmsg_eptdev_open(struct inode *inode, struct file *filp)
+{
+	struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev);
+	struct rpmsg_endpoint *ept;
+	struct rpmsg_device *rpdev = eptdev->rpdev;
+	struct device *dev = &eptdev->dev;
+
+	mutex_lock(&eptdev->ept_lock);
+	if (eptdev->ept) {
+		mutex_unlock(&eptdev->ept_lock);
+		return -EBUSY;
+	}
+
+	if (!eptdev->rpdev) {
+		mutex_unlock(&eptdev->ept_lock);
+		return -ENETRESET;
+	}
+
+	get_device(dev);
+
+	/*
+	 * If the default_ept is set, the rpmsg device default endpoint is used.
+	 * Else a new endpoint is created on open that will be destroyed on release.
+	 */
+	if (eptdev->default_ept)
+		ept = eptdev->default_ept;
+	else
+		ept = rpmsg_create_ept(rpdev, rpmsg_ept_cb, eptdev, eptdev->chinfo);
+
+	if (!ept) {
+		dev_err(dev, "failed to open %s\n", eptdev->chinfo.name);
+		put_device(dev);
+		mutex_unlock(&eptdev->ept_lock);
+		return -EINVAL;
+	}
+
+	ept->flow_cb = rpmsg_ept_flow_cb;
+	eptdev->ept = ept;
+	filp->private_data = eptdev;
+	mutex_unlock(&eptdev->ept_lock);
+
+	return 0;
+}
+
+static int rpmsg_eptdev_release(struct inode *inode, struct file *filp)
+{
+	struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev);
+	struct device *dev = &eptdev->dev;
+
+	/* Close the endpoint, if it's not already destroyed by the parent */
+	mutex_lock(&eptdev->ept_lock);
+	if (eptdev->ept) {
+		if (!eptdev->default_ept)
+			rpmsg_destroy_ept(eptdev->ept);
+		eptdev->ept = NULL;
+	}
+	mutex_unlock(&eptdev->ept_lock);
+	eptdev->remote_flow_updated = false;
+
+	/* Discard all SKBs */
+	skb_queue_purge(&eptdev->queue);
+
+	put_device(dev);
+
+	return 0;
+}
+
+static ssize_t rpmsg_eptdev_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+	struct file *filp = iocb->ki_filp;
+	struct rpmsg_eptdev *eptdev = filp->private_data;
+	unsigned long flags;
+	struct sk_buff *skb;
+	int use;
+
+	if (!eptdev->ept)
+		return -EPIPE;
+
+	spin_lock_irqsave(&eptdev->queue_lock, flags);
+
+	/* Wait for data in the queue */
+	if (skb_queue_empty(&eptdev->queue)) {
+		spin_unlock_irqrestore(&eptdev->queue_lock, flags);
+
+		if (filp->f_flags & O_NONBLOCK)
+			return -EAGAIN;
+
+		/* Wait until we get data or the endpoint goes away */
+		if (wait_event_interruptible(eptdev->readq,
+					     !skb_queue_empty(&eptdev->queue) ||
+					     !eptdev->ept))
+			return -ERESTARTSYS;
+
+		/* We lost the endpoint while waiting */
+		if (!eptdev->ept)
+			return -EPIPE;
+
+		spin_lock_irqsave(&eptdev->queue_lock, flags);
+	}
+
+	skb = skb_dequeue(&eptdev->queue);
+	spin_unlock_irqrestore(&eptdev->queue_lock, flags);
+	if (!skb)
+		return -EFAULT;
+
+	use = min_t(size_t, iov_iter_count(to), skb->len);
+	if (copy_to_iter(skb->data, use, to) != use)
+		use = -EFAULT;
+
+	kfree_skb(skb);
+
+	return use;
+}
+
+static ssize_t rpmsg_eptdev_write_iter(struct kiocb *iocb,
+				       struct iov_iter *from)
+{
+	struct file *filp = iocb->ki_filp;
+	struct rpmsg_eptdev *eptdev = filp->private_data;
+	size_t len = iov_iter_count(from);
+	void *kbuf;
+	int ret;
+
+	kbuf = kzalloc(len, GFP_KERNEL);
+	if (!kbuf)
+		return -ENOMEM;
+
+	if (!copy_from_iter_full(kbuf, len, from)) {
+		ret = -EFAULT;
+		goto free_kbuf;
+	}
+
+	if (mutex_lock_interruptible(&eptdev->ept_lock)) {
+		ret = -ERESTARTSYS;
+		goto free_kbuf;
+	}
+
+	if (!eptdev->ept) {
+		ret = -EPIPE;
+		goto unlock_eptdev;
+	}
+
+	if (filp->f_flags & O_NONBLOCK) {
+		ret = rpmsg_trysendto(eptdev->ept, kbuf, len, eptdev->chinfo.dst);
+		if (ret == -ENOMEM)
+			ret = -EAGAIN;
+	} else {
+		ret = rpmsg_sendto(eptdev->ept, kbuf, len, eptdev->chinfo.dst);
+	}
+
+unlock_eptdev:
+	mutex_unlock(&eptdev->ept_lock);
+
+free_kbuf:
+	kfree(kbuf);
+	return ret < 0 ? ret : len;
+}
+
+static __poll_t rpmsg_eptdev_poll(struct file *filp, poll_table *wait)
+{
+	struct rpmsg_eptdev *eptdev = filp->private_data;
+	__poll_t mask = 0;
+
+	if (!eptdev->ept)
+		return EPOLLERR;
+
+	poll_wait(filp, &eptdev->readq, wait);
+
+	if (!skb_queue_empty(&eptdev->queue))
+		mask |= EPOLLIN | EPOLLRDNORM;
+
+	if (eptdev->remote_flow_updated)
+		mask |= EPOLLPRI;
+
+	mutex_lock(&eptdev->ept_lock);
+	mask |= rpmsg_poll(eptdev->ept, filp, wait);
+	mutex_unlock(&eptdev->ept_lock);
+
+	return mask;
+}
+
+static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd,
+			       unsigned long arg)
+{
+	struct rpmsg_eptdev *eptdev = fp->private_data;
+
+	bool set;
+	int ret;
+
+	switch (cmd) {
+	case RPMSG_GET_OUTGOING_FLOWCONTROL:
+		eptdev->remote_flow_updated = false;
+		ret = put_user(eptdev->remote_flow_restricted, (int __user *)arg);
+		break;
+	case RPMSG_SET_INCOMING_FLOWCONTROL:
+		if (arg > 1) {
+			ret = -EINVAL;
+			break;
+		}
+		set = !!arg;
+		ret = rpmsg_set_flow_control(eptdev->ept, set, eptdev->chinfo.dst);
+		break;
+	case RPMSG_DESTROY_EPT_IOCTL:
+		/* Don't allow to destroy a default endpoint. */
+		if (eptdev->default_ept) {
+			ret = -EINVAL;
+			break;
+		}
+		ret = rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static const struct file_operations rpmsg_eptdev_fops = {
+	.owner = THIS_MODULE,
+	.open = rpmsg_eptdev_open,
+	.release = rpmsg_eptdev_release,
+	.read_iter = rpmsg_eptdev_read_iter,
+	.write_iter = rpmsg_eptdev_write_iter,
+	.poll = rpmsg_eptdev_poll,
+	.unlocked_ioctl = rpmsg_eptdev_ioctl,
+	.compat_ioctl = compat_ptr_ioctl,
+};
+
+static ssize_t name_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%s\n", eptdev->chinfo.name);
+}
+static DEVICE_ATTR_RO(name);
+
+static ssize_t src_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%d\n", eptdev->chinfo.src);
+}
+static DEVICE_ATTR_RO(src);
+
+static ssize_t dst_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);
+
+	return sprintf(buf, "%d\n", eptdev->chinfo.dst);
+}
+static DEVICE_ATTR_RO(dst);
+
+static struct attribute *rpmsg_eptdev_attrs[] = {
+	&dev_attr_name.attr,
+	&dev_attr_src.attr,
+	&dev_attr_dst.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(rpmsg_eptdev);
+
+static void rpmsg_eptdev_release_device(struct device *dev)
+{
+	struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev);
+
+	ida_free(&rpmsg_ept_ida, dev->id);
+	ida_free(&rpmsg_minor_ida, MINOR(eptdev->dev.devt));
+	kfree(eptdev);
+}
+
+static struct rpmsg_eptdev *rpmsg_chrdev_eptdev_alloc(struct rpmsg_device *rpdev,
+						      struct device *parent)
+{
+	struct rpmsg_eptdev *eptdev;
+	struct device *dev;
+
+	eptdev = kzalloc_obj(*eptdev);
+	if (!eptdev)
+		return ERR_PTR(-ENOMEM);
+
+	dev = &eptdev->dev;
+	eptdev->rpdev = rpdev;
+
+	mutex_init(&eptdev->ept_lock);
+	spin_lock_init(&eptdev->queue_lock);
+	skb_queue_head_init(&eptdev->queue);
+	init_waitqueue_head(&eptdev->readq);
+
+	device_initialize(dev);
+	dev->class = &rpmsg_class;
+	dev->parent = parent;
+	dev->groups = rpmsg_eptdev_groups;
+	dev_set_drvdata(dev, eptdev);
+
+	cdev_init(&eptdev->cdev, &rpmsg_eptdev_fops);
+	eptdev->cdev.owner = THIS_MODULE;
+
+	return eptdev;
+}
+
+static int rpmsg_chrdev_eptdev_add(struct rpmsg_eptdev *eptdev, struct rpmsg_channel_info chinfo)
+{
+	struct device *dev = &eptdev->dev;
+	int ret;
+
+	eptdev->chinfo = chinfo;
+
+	ret = ida_alloc_max(&rpmsg_minor_ida, RPMSG_DEV_MAX - 1, GFP_KERNEL);
+	if (ret < 0)
+		goto free_eptdev;
+	dev->devt = MKDEV(MAJOR(rpmsg_major), ret);
+
+	ret = ida_alloc(&rpmsg_ept_ida, GFP_KERNEL);
+	if (ret < 0)
+		goto free_minor_ida;
+	dev->id = ret;
+	dev_set_name(dev, "rpmsg%d", ret);
+
+	ret = cdev_device_add(&eptdev->cdev, &eptdev->dev);
+	if (ret)
+		goto free_ept_ida;
+
+	/* We can now rely on the release function for cleanup */
+	dev->release = rpmsg_eptdev_release_device;
+
+	return ret;
+
+free_ept_ida:
+	ida_free(&rpmsg_ept_ida, dev->id);
+free_minor_ida:
+	ida_free(&rpmsg_minor_ida, MINOR(dev->devt));
+free_eptdev:
+	put_device(dev);
+	kfree(eptdev);
+
+	return ret;
+}
+
+int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent,
+			       struct rpmsg_channel_info chinfo)
+{
+	struct rpmsg_eptdev *eptdev;
+
+	eptdev = rpmsg_chrdev_eptdev_alloc(rpdev, parent);
+	if (IS_ERR(eptdev))
+		return PTR_ERR(eptdev);
+
+	return rpmsg_chrdev_eptdev_add(eptdev, chinfo);
+}
+EXPORT_SYMBOL(rpmsg_chrdev_eptdev_create);
+
+static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev)
+{
+	struct rpmsg_channel_info chinfo;
+	struct rpmsg_eptdev *eptdev;
+	struct device *dev = &rpdev->dev;
+	int ret;
+
+	memcpy(chinfo.name, rpdev->id.name, RPMSG_NAME_SIZE);
+	chinfo.src = rpdev->src;
+	chinfo.dst = rpdev->dst;
+
+	eptdev = rpmsg_chrdev_eptdev_alloc(rpdev, dev);
+	if (IS_ERR(eptdev))
+		return PTR_ERR(eptdev);
+
+	/* Set the default_ept to the rpmsg device endpoint */
+	eptdev->default_ept = rpdev->ept;
+
+	ret = rpmsg_chrdev_eptdev_add(eptdev, chinfo);
+
+	if (ret)
+		return ret;
+	/*
+	 * The rpmsg_ept_cb uses *priv parameter to get its rpmsg_eptdev context.
+	 * Stored it in default_ept *priv field.
+	 */
+	eptdev->default_ept->priv = eptdev;
+
+	return 0;
+}
+
+static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev)
+{
+	int ret;
+
+	ret = device_for_each_child(&rpdev->dev, NULL, rpmsg_chrdev_eptdev_destroy);
+	if (ret)
+		dev_warn(&rpdev->dev, "failed to destroy endpoints: %d\n", ret);
+}
+
+static struct rpmsg_device_id rpmsg_chrdev_id_table[] = {
+	{ .name	= "rpmsg-raw" },
+	{ .name	= "rpmsg_chrdev" },
+	{ },
+};
+MODULE_DEVICE_TABLE(rpmsg, rpmsg_chrdev_id_table);
+
+static struct rpmsg_driver rpmsg_chrdev_driver = {
+	.probe = rpmsg_chrdev_probe,
+	.remove = rpmsg_chrdev_remove,
+	.callback = rpmsg_ept_cb,
+	.id_table = rpmsg_chrdev_id_table,
+	.drv.name = "rpmsg_chrdev",
+};
+
+static int rpmsg_chrdev_init(void)
+{
+	int ret;
+
+	ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg_char");
+	if (ret < 0) {
+		pr_err("failed to allocate char dev region\n");
+		return ret;
+	}
+
+	ret = register_rpmsg_driver(&rpmsg_chrdev_driver);
+	if (ret < 0) {
+		pr_err("rpmsg: failed to register rpmsg raw driver\n");
+		goto free_region;
+	}
+
+	return 0;
+
+free_region:
+	unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
+
+	return ret;
+}
+postcore_initcall(rpmsg_chrdev_init);
+
+static void rpmsg_chrdev_exit(void)
+{
+	unregister_rpmsg_driver(&rpmsg_chrdev_driver);
+	unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
+}
+module_exit(rpmsg_chrdev_exit);
+
+MODULE_DESCRIPTION("RPMSG device interface");
+MODULE_LICENSE("GPL v2");

linux-7.2.3/drivers/rpmsg/rpmsg_char.h

@@ -0,0 +1,46 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2022, STMicroelectronics
+ */
+
+#ifndef __RPMSG_CHRDEV_H__
+#define __RPMSG_CHRDEV_H__
+
+#if IS_ENABLED(CONFIG_RPMSG_CHAR)
+/**
+ * rpmsg_chrdev_eptdev_create() - register char device based on an endpoint
+ * @rpdev:  prepared rpdev to be used for creating endpoints
+ * @parent: parent device
+ * @chinfo: associated endpoint channel information.
+ *
+ * This function create a new rpmsg char endpoint device to instantiate a new
+ * endpoint based on chinfo information.
+ */
+int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent,
+			       struct rpmsg_channel_info chinfo);
+
+/**
+ * rpmsg_chrdev_eptdev_destroy() - destroy created char device endpoint.
+ * @data: private data associated to the endpoint device
+ *
+ * This function destroys a rpmsg char endpoint device created by the RPMSG_DESTROY_EPT_IOCTL
+ * control.
+ */
+int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data);
+
+#else  /*IS_ENABLED(CONFIG_RPMSG_CHAR) */
+
+static inline int rpmsg_chrdev_eptdev_create(struct rpmsg_device *rpdev, struct device *parent,
+					     struct rpmsg_channel_info chinfo)
+{
+	return -ENXIO;
+}
+
+static inline int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data)
+{
+	return -ENXIO;
+}
+
+#endif /*IS_ENABLED(CONFIG_RPMSG_CHAR) */
+
+#endif /*__RPMSG_CHRDEV_H__ */

linux-7.2.3/drivers/rpmsg/rpmsg_core.c

@@ -0,0 +1,638 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * remote processor messaging bus
+ *
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ * Copyright (C) 2011 Google, Inc.
+ *
+ * Ohad Ben-Cohen <ohad@wizery.com>
+ * Brian Swetland <swetland@google.com>
+ */
+
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/rpmsg.h>
+#include <linux/of_device.h>
+#include <linux/pm_domain.h>
+#include <linux/slab.h>
+
+#include "rpmsg_internal.h"
+
+const struct class rpmsg_class = {
+	.name = "rpmsg",
+};
+EXPORT_SYMBOL(rpmsg_class);
+
+/**
+ * rpmsg_create_channel() - create a new rpmsg channel
+ * using its name and address info.
+ * @rpdev: rpmsg device
+ * @chinfo: channel_info to bind
+ *
+ * Return: a pointer to the new rpmsg device on success, or NULL on error.
+ */
+struct rpmsg_device *rpmsg_create_channel(struct rpmsg_device *rpdev,
+					  struct rpmsg_channel_info *chinfo)
+{
+	if (WARN_ON(!rpdev))
+		return NULL;
+	if (!rpdev->ops || !rpdev->ops->create_channel) {
+		dev_err(&rpdev->dev, "no create_channel ops found\n");
+		return NULL;
+	}
+
+	return rpdev->ops->create_channel(rpdev, chinfo);
+}
+EXPORT_SYMBOL(rpmsg_create_channel);
+
+/**
+ * rpmsg_release_channel() - release a rpmsg channel
+ * using its name and address info.
+ * @rpdev: rpmsg device
+ * @chinfo: channel_info to bind
+ *
+ * Return: 0 on success or an appropriate error value.
+ */
+int rpmsg_release_channel(struct rpmsg_device *rpdev,
+			  struct rpmsg_channel_info *chinfo)
+{
+	if (WARN_ON(!rpdev))
+		return -EINVAL;
+	if (!rpdev->ops || !rpdev->ops->release_channel) {
+		dev_err(&rpdev->dev, "no release_channel ops found\n");
+		return -ENXIO;
+	}
+
+	return rpdev->ops->release_channel(rpdev, chinfo);
+}
+EXPORT_SYMBOL(rpmsg_release_channel);
+
+/**
+ * rpmsg_create_ept() - create a new rpmsg_endpoint
+ * @rpdev: rpmsg channel device
+ * @cb: rx callback handler
+ * @priv: private data for the driver's use
+ * @chinfo: channel_info with the local rpmsg address to bind with @cb
+ *
+ * Every rpmsg address in the system is bound to an rx callback (so when
+ * inbound messages arrive, they are dispatched by the rpmsg bus using the
+ * appropriate callback handler) by means of an rpmsg_endpoint struct.
+ *
+ * This function allows drivers to create such an endpoint, and by that,
+ * bind a callback, and possibly some private data too, to an rpmsg address
+ * (either one that is known in advance, or one that will be dynamically
+ * assigned for them).
+ *
+ * Simple rpmsg drivers need not call rpmsg_create_ept, because an endpoint
+ * is already created for them when they are probed by the rpmsg bus
+ * (using the rx callback provided when they registered to the rpmsg bus).
+ *
+ * So things should just work for simple drivers: they already have an
+ * endpoint, their rx callback is bound to their rpmsg address, and when
+ * relevant inbound messages arrive (i.e. messages which their dst address
+ * equals to the src address of their rpmsg channel), the driver's handler
+ * is invoked to process it.
+ *
+ * That said, more complicated drivers might need to allocate
+ * additional rpmsg addresses, and bind them to different rx callbacks.
+ * To accomplish that, those drivers need to call this function.
+ *
+ * Drivers should provide their @rpdev channel (so the new endpoint would belong
+ * to the same remote processor their channel belongs to), an rx callback
+ * function, an optional private data (which is provided back when the
+ * rx callback is invoked), and an address they want to bind with the
+ * callback. If @addr is RPMSG_ADDR_ANY, then rpmsg_create_ept will
+ * dynamically assign them an available rpmsg address (drivers should have
+ * a very good reason why not to always use RPMSG_ADDR_ANY here).
+ *
+ * Return: a pointer to the endpoint on success, or NULL on error.
+ */
+struct rpmsg_endpoint *rpmsg_create_ept(struct rpmsg_device *rpdev,
+					rpmsg_rx_cb_t cb, void *priv,
+					struct rpmsg_channel_info chinfo)
+{
+	if (WARN_ON(!rpdev))
+		return NULL;
+
+	return rpdev->ops->create_ept(rpdev, cb, priv, chinfo);
+}
+EXPORT_SYMBOL(rpmsg_create_ept);
+
+/**
+ * rpmsg_destroy_ept() - destroy an existing rpmsg endpoint
+ * @ept: endpoing to destroy
+ *
+ * Should be used by drivers to destroy an rpmsg endpoint previously
+ * created with rpmsg_create_ept(). As with other types of "free" NULL
+ * is a valid parameter.
+ */
+void rpmsg_destroy_ept(struct rpmsg_endpoint *ept)
+{
+	if (ept && ept->ops)
+		ept->ops->destroy_ept(ept);
+}
+EXPORT_SYMBOL(rpmsg_destroy_ept);
+
+/**
+ * rpmsg_send() - send a message across to the remote processor
+ * @ept: the rpmsg endpoint
+ * @data: payload of message
+ * @len: length of payload
+ *
+ * This function sends @data of length @len on the @ept endpoint.
+ * The message will be sent to the remote processor which the @ept
+ * endpoint belongs to, using @ept's address and its associated rpmsg
+ * device destination addresses.
+ * In case there are no TX buffers available, the function will block until
+ * one becomes available, or a timeout of 15 seconds elapses. When the latter
+ * happens, -ERESTARTSYS is returned.
+ *
+ * Can only be called from process context (for now).
+ *
+ * Return: 0 on success and an appropriate error value on failure.
+ */
+int rpmsg_send(struct rpmsg_endpoint *ept, const void *data, int len)
+{
+	if (WARN_ON(!ept))
+		return -EINVAL;
+	if (!ept->ops->send)
+		return -ENXIO;
+
+	return ept->ops->send(ept, data, len);
+}
+EXPORT_SYMBOL(rpmsg_send);
+
+/**
+ * rpmsg_sendto() - send a message across to the remote processor, specify dst
+ * @ept: the rpmsg endpoint
+ * @data: payload of message
+ * @len: length of payload
+ * @dst: destination address
+ *
+ * This function sends @data of length @len to the remote @dst address.
+ * The message will be sent to the remote processor which the @ept
+ * endpoint belongs to, using @ept's address as source.
+ * In case there are no TX buffers available, the function will block until
+ * one becomes available, or a timeout of 15 seconds elapses. When the latter
+ * happens, -ERESTARTSYS is returned.
+ *
+ * Can only be called from process context (for now).
+ *
+ * Return: 0 on success and an appropriate error value on failure.
+ */
+int rpmsg_sendto(struct rpmsg_endpoint *ept, const void *data, int len, u32 dst)
+{
+	if (WARN_ON(!ept))
+		return -EINVAL;
+	if (!ept->ops->sendto)
+		return -ENXIO;
+
+	return ept->ops->sendto(ept, data, len, dst);
+}
+EXPORT_SYMBOL(rpmsg_sendto);
+
+/**
+ * rpmsg_trysend() - send a message across to the remote processor
+ * @ept: the rpmsg endpoint
+ * @data: payload of message
+ * @len: length of payload
+ *
+ * This function sends @data of length @len on the @ept endpoint.
+ * The message will be sent to the remote processor which the @ept
+ * endpoint belongs to, using @ept's address as source and its associated
+ * rpdev's address as destination.
+ * In case there are no TX buffers available, the function will immediately
+ * return -ENOMEM without waiting until one becomes available.
+ *
+ * Can only be called from process context (for now).
+ *
+ * Return: 0 on success and an appropriate error value on failure.
+ */
+int rpmsg_trysend(struct rpmsg_endpoint *ept, const void *data, int len)
+{
+	if (WARN_ON(!ept))
+		return -EINVAL;
+	if (!ept->ops->trysend)
+		return -ENXIO;
+
+	return ept->ops->trysend(ept, data, len);
+}
+EXPORT_SYMBOL(rpmsg_trysend);
+
+/**
+ * rpmsg_trysendto() - send a message across to the remote processor, specify dst
+ * @ept: the rpmsg endpoint
+ * @data: payload of message
+ * @len: length of payload
+ * @dst: destination address
+ *
+ * This function sends @data of length @len to the remote @dst address.
+ * The message will be sent to the remote processor which the @ept
+ * endpoint belongs to, using @ept's address as source.
+ * In case there are no TX buffers available, the function will immediately
+ * return -ENOMEM without waiting until one becomes available.
+ *
+ * Can only be called from process context (for now).
+ *
+ * Return: 0 on success and an appropriate error value on failure.
+ */
+int rpmsg_trysendto(struct rpmsg_endpoint *ept, const void *data, int len, u32 dst)
+{
+	if (WARN_ON(!ept))
+		return -EINVAL;
+	if (!ept->ops->trysendto)
+		return -ENXIO;
+
+	return ept->ops->trysendto(ept, data, len, dst);
+}
+EXPORT_SYMBOL(rpmsg_trysendto);
+
+/**
+ * rpmsg_poll() - poll the endpoint's send buffers
+ * @ept:	the rpmsg endpoint
+ * @filp:	file for poll_wait()
+ * @wait:	poll_table for poll_wait()
+ *
+ * Return: mask representing the current state of the endpoint's send buffers
+ */
+__poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
+			poll_table *wait)
+{
+	if (WARN_ON(!ept))
+		return 0;
+	if (!ept->ops->poll)
+		return 0;
+
+	return ept->ops->poll(ept, filp, wait);
+}
+EXPORT_SYMBOL(rpmsg_poll);
+
+/**
+ * rpmsg_set_flow_control() - request remote to pause/resume transmission
+ * @ept:	the rpmsg endpoint
+ * @pause:	pause transmission
+ * @dst:	destination address of the endpoint
+ *
+ * Return: 0 on success and an appropriate error value on failure.
+ */
+int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool pause, u32 dst)
+{
+	if (WARN_ON(!ept))
+		return -EINVAL;
+	if (!ept->ops->set_flow_control)
+		return -EOPNOTSUPP;
+
+	return ept->ops->set_flow_control(ept, pause, dst);
+}
+EXPORT_SYMBOL_GPL(rpmsg_set_flow_control);
+
+/**
+ * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
+ * @ept: the rpmsg endpoint
+ *
+ * This function returns maximum buffer size available for a single outgoing message.
+ *
+ * Return: the maximum transmission size on success and an appropriate error
+ * value on failure.
+ */
+
+ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
+{
+	if (WARN_ON(!ept))
+		return -EINVAL;
+	if (!ept->ops->get_mtu)
+		return -ENOTSUPP;
+
+	return ept->ops->get_mtu(ept);
+}
+EXPORT_SYMBOL(rpmsg_get_mtu);
+
+/*
+ * match a rpmsg channel with a channel info struct.
+ * this is used to make sure we're not creating rpmsg devices for channels
+ * that already exist.
+ */
+static int rpmsg_device_match(struct device *dev, const void *data)
+{
+	const struct rpmsg_channel_info *chinfo = data;
+	struct rpmsg_device *rpdev = to_rpmsg_device(dev);
+
+	if (chinfo->src != RPMSG_ADDR_ANY && chinfo->src != rpdev->src)
+		return 0;
+
+	if (chinfo->dst != RPMSG_ADDR_ANY && chinfo->dst != rpdev->dst)
+		return 0;
+
+	if (strncmp(chinfo->name, rpdev->id.name, RPMSG_NAME_SIZE))
+		return 0;
+
+	/* found a match ! */
+	return 1;
+}
+
+struct device *rpmsg_find_device(struct device *parent,
+				 struct rpmsg_channel_info *chinfo)
+{
+	return device_find_child(parent, chinfo, rpmsg_device_match);
+
+}
+EXPORT_SYMBOL(rpmsg_find_device);
+
+/* sysfs show configuration fields */
+#define rpmsg_show_attr(field, path, format_string)			\
+static ssize_t								\
+field##_show(struct device *dev,					\
+			struct device_attribute *attr, char *buf)	\
+{									\
+	struct rpmsg_device *rpdev = to_rpmsg_device(dev);		\
+									\
+	return sprintf(buf, format_string, rpdev->path);		\
+}									\
+static DEVICE_ATTR_RO(field);
+
+/* for more info, see Documentation/ABI/testing/sysfs-bus-rpmsg */
+rpmsg_show_attr(name, id.name, "%s\n");
+rpmsg_show_attr(src, src, "0x%x\n");
+rpmsg_show_attr(dst, dst, "0x%x\n");
+rpmsg_show_attr(announce, announce ? "true" : "false", "%s\n");
+
+static ssize_t modalias_show(struct device *dev,
+			     struct device_attribute *attr, char *buf)
+{
+	struct rpmsg_device *rpdev = to_rpmsg_device(dev);
+	ssize_t len;
+
+	len = of_device_modalias(dev, buf, PAGE_SIZE);
+	if (len != -ENODEV)
+		return len;
+
+	return sprintf(buf, RPMSG_DEVICE_MODALIAS_FMT "\n", rpdev->id.name);
+}
+static DEVICE_ATTR_RO(modalias);
+
+static struct attribute *rpmsg_dev_attrs[] = {
+	&dev_attr_name.attr,
+	&dev_attr_modalias.attr,
+	&dev_attr_dst.attr,
+	&dev_attr_src.attr,
+	&dev_attr_announce.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(rpmsg_dev);
+
+/* rpmsg devices and drivers are matched using the service name */
+static inline int rpmsg_id_match(const struct rpmsg_device *rpdev,
+				  const struct rpmsg_device_id *id)
+{
+	return strncmp(id->name, rpdev->id.name, RPMSG_NAME_SIZE) == 0;
+}
+
+/* match rpmsg channel and rpmsg driver */
+static int rpmsg_dev_match(struct device *dev, const struct device_driver *drv)
+{
+	struct rpmsg_device *rpdev = to_rpmsg_device(dev);
+	const struct rpmsg_driver *rpdrv = to_rpmsg_driver(drv);
+	const struct rpmsg_device_id *ids = rpdrv->id_table;
+	unsigned int i;
+	int ret;
+
+	ret = device_match_driver_override(dev, drv);
+	if (ret >= 0)
+		return ret;
+
+	if (ids)
+		for (i = 0; ids[i].name[0]; i++)
+			if (rpmsg_id_match(rpdev, &ids[i])) {
+				rpdev->id.driver_data = ids[i].driver_data;
+				return 1;
+			}
+
+	return of_driver_match_device(dev, drv);
+}
+
+static int rpmsg_uevent(const struct device *dev, struct kobj_uevent_env *env)
+{
+	const struct rpmsg_device *rpdev = to_rpmsg_device(dev);
+	int ret;
+
+	ret = of_device_uevent_modalias(dev, env);
+	if (ret != -ENODEV)
+		return ret;
+
+	return add_uevent_var(env, "MODALIAS=" RPMSG_DEVICE_MODALIAS_FMT,
+					rpdev->id.name);
+}
+
+/*
+ * when an rpmsg driver is probed with a channel, we seamlessly create
+ * it an endpoint, binding its rx callback to a unique local rpmsg
+ * address.
+ *
+ * if we need to, we also announce about this channel to the remote
+ * processor (needed in case the driver is exposing an rpmsg service).
+ */
+static int rpmsg_dev_probe(struct device *dev)
+{
+	struct rpmsg_device *rpdev = to_rpmsg_device(dev);
+	struct rpmsg_driver *rpdrv = to_rpmsg_driver(rpdev->dev.driver);
+	struct rpmsg_channel_info chinfo = {};
+	struct rpmsg_endpoint *ept = NULL;
+	int err;
+
+	err = dev_pm_domain_attach(dev, PD_FLAG_ATTACH_POWER_ON |
+					PD_FLAG_DETACH_POWER_OFF);
+	if (err)
+		goto out;
+
+	if (rpdrv->callback) {
+		strscpy(chinfo.name, rpdev->id.name, sizeof(chinfo.name));
+		chinfo.src = rpdev->src;
+		chinfo.dst = RPMSG_ADDR_ANY;
+
+		ept = rpmsg_create_ept(rpdev, rpdrv->callback, NULL, chinfo);
+		if (!ept) {
+			dev_err(dev, "failed to create endpoint\n");
+			err = -ENOMEM;
+			goto out;
+		}
+
+		rpdev->ept = ept;
+		rpdev->src = ept->addr;
+
+		ept->flow_cb = rpdrv->flowcontrol;
+	}
+
+	err = rpdrv->probe(rpdev);
+	if (err) {
+		dev_err(dev, "%s: failed: %d\n", __func__, err);
+		goto destroy_ept;
+	}
+
+	if (ept && rpdev->ops->announce_create) {
+		err = rpdev->ops->announce_create(rpdev);
+		if (err) {
+			dev_err(dev, "failed to announce creation\n");
+			goto remove_rpdev;
+		}
+	}
+
+	return 0;
+
+remove_rpdev:
+	if (rpdrv->remove)
+		rpdrv->remove(rpdev);
+destroy_ept:
+	if (ept)
+		rpmsg_destroy_ept(ept);
+out:
+	return err;
+}
+
+static void rpmsg_dev_remove(struct device *dev)
+{
+	struct rpmsg_device *rpdev = to_rpmsg_device(dev);
+	struct rpmsg_driver *rpdrv = to_rpmsg_driver(rpdev->dev.driver);
+
+	if (rpdev->ops->announce_destroy)
+		rpdev->ops->announce_destroy(rpdev);
+
+	if (rpdrv->remove)
+		rpdrv->remove(rpdev);
+
+	if (rpdev->ept)
+		rpmsg_destroy_ept(rpdev->ept);
+}
+
+static const struct bus_type rpmsg_bus = {
+	.name		= "rpmsg",
+	.match		= rpmsg_dev_match,
+	.dev_groups	= rpmsg_dev_groups,
+	.driver_override = true,
+	.uevent		= rpmsg_uevent,
+	.probe		= rpmsg_dev_probe,
+	.remove		= rpmsg_dev_remove,
+};
+
+/*
+ * A helper for registering rpmsg device with driver override and name.
+ * Drivers should not be using it, but instead rpmsg_register_device().
+ */
+int rpmsg_register_device_override(struct rpmsg_device *rpdev,
+				   const char *driver_override)
+{
+	struct device *dev = &rpdev->dev;
+	int ret;
+
+	if (driver_override)
+		strscpy_pad(rpdev->id.name, driver_override, RPMSG_NAME_SIZE);
+
+	dev_set_name(dev, "%s.%s.%d.%d", dev_name(dev->parent),
+		     rpdev->id.name, rpdev->src, rpdev->dst);
+
+	dev->bus = &rpmsg_bus;
+
+	device_initialize(dev);
+	if (driver_override) {
+		ret = device_set_driver_override(dev, driver_override);
+		if (ret) {
+			dev_err(dev, "device_set_driver_override() failed: %d\n", ret);
+			put_device(dev);
+			return ret;
+		}
+	}
+
+	ret = device_add(dev);
+	if (ret) {
+		dev_err(dev, "device_add failed: %d\n", ret);
+		put_device(dev);
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL(rpmsg_register_device_override);
+
+int rpmsg_register_device(struct rpmsg_device *rpdev)
+{
+	return rpmsg_register_device_override(rpdev, NULL);
+}
+EXPORT_SYMBOL(rpmsg_register_device);
+
+/*
+ * find an existing channel using its name + address properties,
+ * and destroy it
+ */
+int rpmsg_unregister_device(struct device *parent,
+			    struct rpmsg_channel_info *chinfo)
+{
+	struct device *dev;
+
+	dev = rpmsg_find_device(parent, chinfo);
+	if (!dev)
+		return -EINVAL;
+
+	device_unregister(dev);
+
+	put_device(dev);
+
+	return 0;
+}
+EXPORT_SYMBOL(rpmsg_unregister_device);
+
+/**
+ * __register_rpmsg_driver() - register an rpmsg driver with the rpmsg bus
+ * @rpdrv: pointer to a struct rpmsg_driver
+ * @owner: owning module/driver
+ *
+ * Return: 0 on success, and an appropriate error value on failure.
+ */
+int __register_rpmsg_driver(struct rpmsg_driver *rpdrv, struct module *owner)
+{
+	rpdrv->drv.bus = &rpmsg_bus;
+	rpdrv->drv.owner = owner;
+	return driver_register(&rpdrv->drv);
+}
+EXPORT_SYMBOL(__register_rpmsg_driver);
+
+/**
+ * unregister_rpmsg_driver() - unregister an rpmsg driver from the rpmsg bus
+ * @rpdrv: pointer to a struct rpmsg_driver
+ *
+ * Return: 0 on success, and an appropriate error value on failure.
+ */
+void unregister_rpmsg_driver(struct rpmsg_driver *rpdrv)
+{
+	driver_unregister(&rpdrv->drv);
+}
+EXPORT_SYMBOL(unregister_rpmsg_driver);
+
+
+static int __init rpmsg_init(void)
+{
+	int ret;
+
+	ret = class_register(&rpmsg_class);
+	if (ret) {
+		pr_err("failed to register rpmsg class\n");
+		return ret;
+	}
+
+	ret = bus_register(&rpmsg_bus);
+	if (ret) {
+		pr_err("failed to register rpmsg bus: %d\n", ret);
+		class_unregister(&rpmsg_class);
+	}
+	return ret;
+}
+postcore_initcall(rpmsg_init);
+
+static void __exit rpmsg_fini(void)
+{
+	bus_unregister(&rpmsg_bus);
+	class_unregister(&rpmsg_class);
+}
+module_exit(rpmsg_fini);
+
+MODULE_DESCRIPTION("remote processor messaging bus");
+MODULE_LICENSE("GPL v2");

linux-7.2.3/drivers/rpmsg/rpmsg_ctrl.c

@@ -0,0 +1,245 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022, STMicroelectronics
+ * Copyright (c) 2016, Linaro Ltd.
+ * Copyright (c) 2012, Michal Simek <monstr@monstr.eu>
+ * Copyright (c) 2012, PetaLogix
+ * Copyright (c) 2011, Texas Instruments, Inc.
+ * Copyright (c) 2011, Google, Inc.
+ *
+ * Based on rpmsg performance statistics driver by Michal Simek, which in turn
+ * was based on TI & Google OMX rpmsg driver.
+ */
+
+#define pr_fmt(fmt)		KBUILD_MODNAME ": " fmt
+
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/idr.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/rpmsg.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <uapi/linux/rpmsg.h>
+
+#include "rpmsg_char.h"
+#include "rpmsg_internal.h"
+
+#define RPMSG_DEV_MAX	(MINORMASK + 1)
+
+static dev_t rpmsg_major;
+
+static DEFINE_IDA(rpmsg_ctrl_ida);
+static DEFINE_IDA(rpmsg_minor_ida);
+
+#define dev_to_ctrldev(dev) container_of(dev, struct rpmsg_ctrldev, dev)
+#define cdev_to_ctrldev(i_cdev) container_of(i_cdev, struct rpmsg_ctrldev, cdev)
+
+/**
+ * struct rpmsg_ctrldev - control device for instantiating endpoint devices
+ * @rpdev:	underlaying rpmsg device
+ * @cdev:	cdev for the ctrl device
+ * @dev:	device for the ctrl device
+ * @ctrl_lock:	serialize the ioctrls.
+ */
+struct rpmsg_ctrldev {
+	struct rpmsg_device *rpdev;
+	struct cdev cdev;
+	struct device dev;
+	struct mutex ctrl_lock;
+};
+
+static int rpmsg_ctrldev_open(struct inode *inode, struct file *filp)
+{
+	struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev);
+
+	get_device(&ctrldev->dev);
+	filp->private_data = ctrldev;
+
+	return 0;
+}
+
+static int rpmsg_ctrldev_release(struct inode *inode, struct file *filp)
+{
+	struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev);
+
+	put_device(&ctrldev->dev);
+
+	return 0;
+}
+
+static long rpmsg_ctrldev_ioctl(struct file *fp, unsigned int cmd,
+				unsigned long arg)
+{
+	struct rpmsg_ctrldev *ctrldev = fp->private_data;
+	void __user *argp = (void __user *)arg;
+	struct rpmsg_endpoint_info eptinfo;
+	struct rpmsg_channel_info chinfo;
+	struct rpmsg_device *rpdev;
+	int ret = 0;
+
+	if (copy_from_user(&eptinfo, argp, sizeof(eptinfo)))
+		return -EFAULT;
+
+	memcpy(chinfo.name, eptinfo.name, RPMSG_NAME_SIZE);
+	chinfo.name[RPMSG_NAME_SIZE - 1] = '\0';
+	chinfo.src = eptinfo.src;
+	chinfo.dst = eptinfo.dst;
+
+	mutex_lock(&ctrldev->ctrl_lock);
+	switch (cmd) {
+	case RPMSG_CREATE_EPT_IOCTL:
+		ret = rpmsg_chrdev_eptdev_create(ctrldev->rpdev, &ctrldev->dev, chinfo);
+		break;
+
+	case RPMSG_CREATE_DEV_IOCTL:
+		rpdev = rpmsg_create_channel(ctrldev->rpdev, &chinfo);
+		if (!rpdev) {
+			dev_err(&ctrldev->dev, "failed to create %s channel\n", chinfo.name);
+			ret = -ENXIO;
+		}
+		break;
+
+	case RPMSG_RELEASE_DEV_IOCTL:
+		ret = rpmsg_release_channel(ctrldev->rpdev, &chinfo);
+		if (ret)
+			dev_err(&ctrldev->dev, "failed to release %s channel (%d)\n",
+				chinfo.name, ret);
+		break;
+
+	default:
+		ret = -EINVAL;
+	}
+	mutex_unlock(&ctrldev->ctrl_lock);
+
+	return ret;
+};
+
+static const struct file_operations rpmsg_ctrldev_fops = {
+	.owner = THIS_MODULE,
+	.open = rpmsg_ctrldev_open,
+	.release = rpmsg_ctrldev_release,
+	.unlocked_ioctl = rpmsg_ctrldev_ioctl,
+	.compat_ioctl = compat_ptr_ioctl,
+};
+
+static void rpmsg_ctrldev_release_device(struct device *dev)
+{
+	struct rpmsg_ctrldev *ctrldev = dev_to_ctrldev(dev);
+
+	ida_free(&rpmsg_ctrl_ida, dev->id);
+	ida_free(&rpmsg_minor_ida, MINOR(dev->devt));
+	kfree(ctrldev);
+}
+
+static int rpmsg_ctrldev_probe(struct rpmsg_device *rpdev)
+{
+	struct rpmsg_ctrldev *ctrldev;
+	struct device *dev;
+	int ret;
+
+	ctrldev = kzalloc_obj(*ctrldev);
+	if (!ctrldev)
+		return -ENOMEM;
+
+	ctrldev->rpdev = rpdev;
+
+	dev = &ctrldev->dev;
+	device_initialize(dev);
+	dev->parent = &rpdev->dev;
+	dev->class = &rpmsg_class;
+
+	mutex_init(&ctrldev->ctrl_lock);
+	cdev_init(&ctrldev->cdev, &rpmsg_ctrldev_fops);
+	ctrldev->cdev.owner = THIS_MODULE;
+
+	ret = ida_alloc_max(&rpmsg_minor_ida, RPMSG_DEV_MAX - 1, GFP_KERNEL);
+	if (ret < 0)
+		goto free_ctrldev;
+	dev->devt = MKDEV(MAJOR(rpmsg_major), ret);
+
+	ret = ida_alloc(&rpmsg_ctrl_ida, GFP_KERNEL);
+	if (ret < 0)
+		goto free_minor_ida;
+	dev->id = ret;
+	dev_set_name(&ctrldev->dev, "rpmsg_ctrl%d", ret);
+
+	ret = cdev_device_add(&ctrldev->cdev, &ctrldev->dev);
+	if (ret)
+		goto free_ctrl_ida;
+
+	/* We can now rely on the release function for cleanup */
+	dev->release = rpmsg_ctrldev_release_device;
+
+	dev_set_drvdata(&rpdev->dev, ctrldev);
+
+	return ret;
+
+free_ctrl_ida:
+	ida_free(&rpmsg_ctrl_ida, dev->id);
+free_minor_ida:
+	ida_free(&rpmsg_minor_ida, MINOR(dev->devt));
+free_ctrldev:
+	put_device(dev);
+	kfree(ctrldev);
+
+	return ret;
+}
+
+static void rpmsg_ctrldev_remove(struct rpmsg_device *rpdev)
+{
+	struct rpmsg_ctrldev *ctrldev = dev_get_drvdata(&rpdev->dev);
+	int ret;
+
+	mutex_lock(&ctrldev->ctrl_lock);
+	/* Destroy all endpoints */
+	ret = device_for_each_child(&ctrldev->dev, NULL, rpmsg_chrdev_eptdev_destroy);
+	if (ret)
+		dev_warn(&rpdev->dev, "failed to nuke endpoints: %d\n", ret);
+	mutex_unlock(&ctrldev->ctrl_lock);
+
+	cdev_device_del(&ctrldev->cdev, &ctrldev->dev);
+	put_device(&ctrldev->dev);
+}
+
+static struct rpmsg_driver rpmsg_ctrldev_driver = {
+	.probe = rpmsg_ctrldev_probe,
+	.remove = rpmsg_ctrldev_remove,
+	.drv = {
+		.name = "rpmsg_ctrl",
+	},
+};
+
+static int rpmsg_ctrldev_init(void)
+{
+	int ret;
+
+	ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg_ctrl");
+	if (ret < 0) {
+		pr_err("failed to allocate char dev region\n");
+		return ret;
+	}
+
+	ret = register_rpmsg_driver(&rpmsg_ctrldev_driver);
+	if (ret < 0) {
+		pr_err("failed to register rpmsg driver\n");
+		unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
+	}
+
+	return ret;
+}
+postcore_initcall(rpmsg_ctrldev_init);
+
+static void rpmsg_ctrldev_exit(void)
+{
+	unregister_rpmsg_driver(&rpmsg_ctrldev_driver);
+	unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
+}
+module_exit(rpmsg_ctrldev_exit);
+
+MODULE_DESCRIPTION("rpmsg control interface");
+MODULE_ALIAS("rpmsg:" KBUILD_MODNAME);
+MODULE_LICENSE("GPL v2");

linux-7.2.3/drivers/rpmsg/rpmsg_internal.h

@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * remote processor messaging bus internals
+ *
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ * Copyright (C) 2011 Google, Inc.
+ *
+ * Ohad Ben-Cohen <ohad@wizery.com>
+ * Brian Swetland <swetland@google.com>
+ */
+
+#ifndef __RPMSG_INTERNAL_H__
+#define __RPMSG_INTERNAL_H__
+
+#include <linux/rpmsg.h>
+#include <linux/poll.h>
+
+#define to_rpmsg_device(d) container_of(d, struct rpmsg_device, dev)
+#define to_rpmsg_driver(d) container_of_const(d, struct rpmsg_driver, drv)
+
+extern const struct class rpmsg_class;
+
+/**
+ * struct rpmsg_device_ops - indirection table for the rpmsg_device operations
+ * @create_channel:	create backend-specific channel, optional
+ * @release_channel:	release backend-specific channel, optional
+ * @create_ept:		create backend-specific endpoint, required
+ * @announce_create:	announce presence of new channel, optional
+ * @announce_destroy:	announce destruction of channel, optional
+ *
+ * Indirection table for the operations that a rpmsg backend should implement.
+ * @announce_create and @announce_destroy are optional as the backend might
+ * advertise new channels implicitly by creating the endpoints.
+ */
+struct rpmsg_device_ops {
+	struct rpmsg_device *(*create_channel)(struct rpmsg_device *rpdev,
+					       struct rpmsg_channel_info *chinfo);
+	int (*release_channel)(struct rpmsg_device *rpdev,
+			       struct rpmsg_channel_info *chinfo);
+	struct rpmsg_endpoint *(*create_ept)(struct rpmsg_device *rpdev,
+					    rpmsg_rx_cb_t cb, void *priv,
+					    struct rpmsg_channel_info chinfo);
+
+	int (*announce_create)(struct rpmsg_device *rpdev);
+	int (*announce_destroy)(struct rpmsg_device *rpdev);
+};
+
+/**
+ * struct rpmsg_endpoint_ops - indirection table for rpmsg_endpoint operations
+ * @destroy_ept:	see @rpmsg_destroy_ept(), required
+ * @send:		see @rpmsg_send(), required
+ * @sendto:		see @rpmsg_sendto(), optional
+ * @trysend:		see @rpmsg_trysend(), required
+ * @trysendto:		see @rpmsg_trysendto(), optional
+ * @poll:		see @rpmsg_poll(), optional
+ * @set_flow_control:	see @rpmsg_set_flow_control(), optional
+ * @get_mtu:		see @rpmsg_get_mtu(), optional
+ *
+ * Indirection table for the operations that a rpmsg backend should implement.
+ * In addition to @destroy_ept, the backend must at least implement @send and
+ * @trysend, while the variants sending data off-channel are optional.
+ */
+struct rpmsg_endpoint_ops {
+	void (*destroy_ept)(struct rpmsg_endpoint *ept);
+
+	int (*send)(struct rpmsg_endpoint *ept, const void *data, int len);
+	int (*sendto)(struct rpmsg_endpoint *ept, const void *data, int len, u32 dst);
+
+	int (*trysend)(struct rpmsg_endpoint *ept, const void *data, int len);
+	int (*trysendto)(struct rpmsg_endpoint *ept, const void *data, int len, u32 dst);
+	__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
+			     poll_table *wait);
+	int (*set_flow_control)(struct rpmsg_endpoint *ept, bool pause, u32 dst);
+	ssize_t (*get_mtu)(struct rpmsg_endpoint *ept);
+};
+
+struct device *rpmsg_find_device(struct device *parent,
+				 struct rpmsg_channel_info *chinfo);
+
+struct rpmsg_device *rpmsg_create_channel(struct rpmsg_device *rpdev,
+					  struct rpmsg_channel_info *chinfo);
+int rpmsg_release_channel(struct rpmsg_device *rpdev,
+			  struct rpmsg_channel_info *chinfo);
+/**
+ * rpmsg_ctrldev_register_device() - register a char device for control based on rpdev
+ * @rpdev:	prepared rpdev to be used for creating endpoints
+ *
+ * This function wraps rpmsg_register_device() preparing the rpdev for use as
+ * basis for the rpmsg chrdev.
+ */
+static inline int rpmsg_ctrldev_register_device(struct rpmsg_device *rpdev)
+{
+	return rpmsg_register_device_override(rpdev, "rpmsg_ctrl");
+}
+
+#endif

linux-7.2.3/drivers/rpmsg/rpmsg_ns.c

@@ -0,0 +1,124 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) STMicroelectronics 2020 - All Rights Reserved
+ */
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/rpmsg.h>
+#include <linux/rpmsg/ns.h>
+#include <linux/slab.h>
+
+#include "rpmsg_internal.h"
+
+/**
+ * rpmsg_ns_register_device() - register name service device based on rpdev
+ * @rpdev: prepared rpdev to be used for creating endpoints
+ *
+ * This function wraps rpmsg_register_device() preparing the rpdev for use as
+ * basis for the rpmsg name service device.
+ */
+int rpmsg_ns_register_device(struct rpmsg_device *rpdev)
+{
+	rpdev->src = RPMSG_NS_ADDR;
+	rpdev->dst = RPMSG_NS_ADDR;
+
+	return rpmsg_register_device_override(rpdev, "rpmsg_ns");
+}
+EXPORT_SYMBOL(rpmsg_ns_register_device);
+
+/* invoked when a name service announcement arrives */
+static int rpmsg_ns_cb(struct rpmsg_device *rpdev, void *data, int len,
+		       void *priv, u32 src)
+{
+	struct rpmsg_ns_msg *msg = data;
+	struct rpmsg_device *newch;
+	struct rpmsg_channel_info chinfo;
+	struct device *dev = rpdev->dev.parent;
+	int ret;
+
+#if defined(CONFIG_DYNAMIC_DEBUG)
+	dynamic_hex_dump("NS announcement: ", DUMP_PREFIX_NONE, 16, 1,
+			 data, len, true);
+#endif
+
+	if (len != sizeof(*msg)) {
+		dev_err(dev, "malformed ns msg (%d)\n", len);
+		return -EINVAL;
+	}
+
+	/* don't trust the remote processor for null terminating the name */
+	msg->name[RPMSG_NAME_SIZE - 1] = '\0';
+
+	strscpy_pad(chinfo.name, msg->name, sizeof(chinfo.name));
+	chinfo.src = RPMSG_ADDR_ANY;
+	chinfo.dst = rpmsg32_to_cpu(rpdev, msg->addr);
+
+	dev_info(dev, "%sing channel %s addr 0x%x\n",
+		 rpmsg32_to_cpu(rpdev, msg->flags) & RPMSG_NS_DESTROY ?
+		 "destroy" : "creat", msg->name, chinfo.dst);
+
+	if (rpmsg32_to_cpu(rpdev, msg->flags) & RPMSG_NS_DESTROY) {
+		ret = rpmsg_release_channel(rpdev, &chinfo);
+		if (ret)
+			dev_err(dev, "rpmsg_destroy_channel failed: %d\n", ret);
+	} else {
+		newch = rpmsg_create_channel(rpdev, &chinfo);
+		if (!newch)
+			dev_err(dev, "rpmsg_create_channel failed\n");
+	}
+
+	return 0;
+}
+
+static int rpmsg_ns_probe(struct rpmsg_device *rpdev)
+{
+	struct rpmsg_endpoint *ns_ept;
+	struct rpmsg_channel_info ns_chinfo = {
+		.src = RPMSG_NS_ADDR,
+		.dst = RPMSG_NS_ADDR,
+		.name = "name_service",
+	};
+
+	/*
+	 * Create the NS announcement service endpoint associated to the RPMsg
+	 * device. The endpoint will be automatically destroyed when the RPMsg
+	 * device will be deleted.
+	 */
+	ns_ept = rpmsg_create_ept(rpdev, rpmsg_ns_cb, NULL, ns_chinfo);
+	if (!ns_ept) {
+		dev_err(&rpdev->dev, "failed to create the ns ept\n");
+		return -ENOMEM;
+	}
+	rpdev->ept = ns_ept;
+
+	return 0;
+}
+
+static struct rpmsg_driver rpmsg_ns_driver = {
+	.drv.name = KBUILD_MODNAME,
+	.probe = rpmsg_ns_probe,
+};
+
+static int rpmsg_ns_init(void)
+{
+	int ret;
+
+	ret = register_rpmsg_driver(&rpmsg_ns_driver);
+	if (ret < 0)
+		pr_err("%s: Failed to register rpmsg driver\n", __func__);
+
+	return ret;
+}
+postcore_initcall(rpmsg_ns_init);
+
+static void rpmsg_ns_exit(void)
+{
+	unregister_rpmsg_driver(&rpmsg_ns_driver);
+}
+module_exit(rpmsg_ns_exit);
+
+MODULE_DESCRIPTION("Name service announcement rpmsg driver");
+MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>");
+MODULE_ALIAS("rpmsg:" KBUILD_MODNAME);
+MODULE_LICENSE("GPL v2");