Resguardo inicial

linux-7.2.3/drivers/misc/bcm-vk/Kconfig

@@ -0,0 +1,29 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Broadcom VK device
+#
+config BCM_VK
+	tristate "Support for Broadcom VK Accelerators"
+	depends on PCI_MSI
+	help
+	  Select this option to enable support for Broadcom
+	  VK Accelerators.  VK is used for performing
+	  multiple specific offload processing tasks in parallel.
+	  Such offload tasks assist in such operations as video
+	  transcoding, compression, and crypto tasks.
+	  This driver enables userspace programs to access these
+	  accelerators via /dev/bcm-vk.N devices.
+
+	  If unsure, say N.
+
+config BCM_VK_TTY
+	bool "Enable tty ports on a Broadcom VK Accelerator device"
+	depends on TTY
+	depends on BCM_VK
+	help
+	  Select this option to enable tty support to allow console
+	  access to Broadcom VK Accelerator cards from host.
+
+	  Device node will in the form /dev/bcm-vk.x_ttyVKy where:
+	  x is the instance of the VK card
+	  y is the tty device number on the VK card.

linux-7.2.3/drivers/misc/bcm-vk/Makefile

@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for Broadcom VK driver
+#
+
+obj-$(CONFIG_BCM_VK) += bcm_vk.o
+bcm_vk-objs := \
+	bcm_vk_dev.o \
+	bcm_vk_msg.o \
+	bcm_vk_sg.o
+
+bcm_vk-$(CONFIG_BCM_VK_TTY) += bcm_vk_tty.o

linux-7.2.3/drivers/misc/bcm-vk/bcm_vk.h

@@ -0,0 +1,548 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2018-2020 Broadcom.
+ */
+
+#ifndef BCM_VK_H
+#define BCM_VK_H
+
+#include <linux/atomic.h>
+#include <linux/firmware.h>
+#include <linux/irq.h>
+#include <linux/kref.h>
+#include <linux/miscdevice.h>
+#include <linux/mutex.h>
+#include <linux/pci.h>
+#include <linux/poll.h>
+#include <linux/sched/signal.h>
+#include <linux/tty.h>
+#include <linux/uaccess.h>
+#include <uapi/linux/misc/bcm_vk.h>
+
+#include "bcm_vk_msg.h"
+
+#define DRV_MODULE_NAME		"bcm-vk"
+
+/*
+ * Load Image is completed in two stages:
+ *
+ * 1) When the VK device boot-up, M7 CPU runs and executes the BootROM.
+ * The Secure Boot Loader (SBL) as part of the BootROM will run
+ * to open up ITCM for host to push BOOT1 image.
+ * SBL will authenticate the image before jumping to BOOT1 image.
+ *
+ * 2) Because BOOT1 image is a secured image, we also called it the
+ * Secure Boot Image (SBI). At second stage, SBI will initialize DDR
+ * and wait for host to push BOOT2 image to DDR.
+ * SBI will authenticate the image before jumping to BOOT2 image.
+ *
+ */
+/* Location of registers of interest in BAR0 */
+
+/* Request register for Secure Boot Loader (SBL) download */
+#define BAR_CODEPUSH_SBL		0x400
+/* Start of ITCM */
+#define CODEPUSH_BOOT1_ENTRY		0x00400000
+#define CODEPUSH_MASK		        0xfffff000
+#define CODEPUSH_BOOTSTART		BIT(0)
+
+/* Boot Status register */
+#define BAR_BOOT_STATUS			0x404
+
+#define SRAM_OPEN			BIT(16)
+#define DDR_OPEN			BIT(17)
+
+/* Firmware loader progress status definitions */
+#define FW_LOADER_ACK_SEND_MORE_DATA	BIT(18)
+#define FW_LOADER_ACK_IN_PROGRESS	BIT(19)
+#define FW_LOADER_ACK_RCVD_ALL_DATA	BIT(20)
+
+/* Boot1/2 is running in standalone mode */
+#define BOOT_STDALONE_RUNNING		BIT(21)
+
+/* definitions for boot status register */
+#define BOOT_STATE_MASK			(0xffffffff & \
+					 ~(FW_LOADER_ACK_SEND_MORE_DATA | \
+					   FW_LOADER_ACK_IN_PROGRESS | \
+					   BOOT_STDALONE_RUNNING))
+
+#define BOOT_ERR_SHIFT			4
+#define BOOT_ERR_MASK			(0xf << BOOT_ERR_SHIFT)
+#define BOOT_PROG_MASK			0xf
+
+#define BROM_STATUS_NOT_RUN		0x2
+#define BROM_NOT_RUN			(SRAM_OPEN | BROM_STATUS_NOT_RUN)
+#define BROM_STATUS_COMPLETE		0x6
+#define BROM_RUNNING			(SRAM_OPEN | BROM_STATUS_COMPLETE)
+#define BOOT1_STATUS_COMPLETE		0x6
+#define BOOT1_RUNNING			(DDR_OPEN | BOOT1_STATUS_COMPLETE)
+#define BOOT2_STATUS_COMPLETE		0x6
+#define BOOT2_RUNNING			(FW_LOADER_ACK_RCVD_ALL_DATA | \
+					 BOOT2_STATUS_COMPLETE)
+
+/* Boot request for Secure Boot Image (SBI) */
+#define BAR_CODEPUSH_SBI		0x408
+/* 64M mapped to BAR2 */
+#define CODEPUSH_BOOT2_ENTRY		0x60000000
+
+#define BAR_CARD_STATUS			0x410
+/* CARD_STATUS definitions */
+#define CARD_STATUS_TTYVK0_READY	BIT(0)
+#define CARD_STATUS_TTYVK1_READY	BIT(1)
+
+#define BAR_BOOT1_STDALONE_PROGRESS	0x420
+#define BOOT1_STDALONE_SUCCESS		(BIT(13) | BIT(14))
+#define BOOT1_STDALONE_PROGRESS_MASK	BOOT1_STDALONE_SUCCESS
+
+#define BAR_METADATA_VERSION		0x440
+#define BAR_OS_UPTIME			0x444
+#define BAR_CHIP_ID			0x448
+#define MAJOR_SOC_REV(_chip_id)		(((_chip_id) >> 20) & 0xf)
+
+#define BAR_CARD_TEMPERATURE		0x45c
+/* defines for all temperature sensor */
+#define BCM_VK_TEMP_FIELD_MASK		0xff
+#define BCM_VK_CPU_TEMP_SHIFT		0
+#define BCM_VK_DDR0_TEMP_SHIFT		8
+#define BCM_VK_DDR1_TEMP_SHIFT		16
+
+#define BAR_CARD_VOLTAGE		0x460
+/* defines for voltage rail conversion */
+#define BCM_VK_VOLT_RAIL_MASK		0xffff
+#define BCM_VK_3P3_VOLT_REG_SHIFT	16
+
+#define BAR_CARD_ERR_LOG		0x464
+/* Error log register bit definition - register for error alerts */
+#define ERR_LOG_UECC			BIT(0)
+#define ERR_LOG_SSIM_BUSY		BIT(1)
+#define ERR_LOG_AFBC_BUSY		BIT(2)
+#define ERR_LOG_HIGH_TEMP_ERR		BIT(3)
+#define ERR_LOG_WDOG_TIMEOUT		BIT(4)
+#define ERR_LOG_SYS_FAULT		BIT(5)
+#define ERR_LOG_RAMDUMP			BIT(6)
+#define ERR_LOG_COP_WDOG_TIMEOUT	BIT(7)
+/* warnings */
+#define ERR_LOG_MEM_ALLOC_FAIL		BIT(8)
+#define ERR_LOG_LOW_TEMP_WARN		BIT(9)
+#define ERR_LOG_ECC			BIT(10)
+#define ERR_LOG_IPC_DWN			BIT(11)
+
+/* Alert bit definitions detectd on host */
+#define ERR_LOG_HOST_INTF_V_FAIL	BIT(13)
+#define ERR_LOG_HOST_HB_FAIL		BIT(14)
+#define ERR_LOG_HOST_PCIE_DWN		BIT(15)
+
+#define BAR_CARD_ERR_MEM		0x468
+/* defines for mem err, all fields have same width */
+#define BCM_VK_MEM_ERR_FIELD_MASK	0xff
+#define BCM_VK_ECC_MEM_ERR_SHIFT	0
+#define BCM_VK_UECC_MEM_ERR_SHIFT	8
+/* threshold of event occurrence and logs start to come out */
+#define BCM_VK_ECC_THRESHOLD		10
+#define BCM_VK_UECC_THRESHOLD		1
+
+#define BAR_CARD_PWR_AND_THRE		0x46c
+/* defines for power and temp threshold, all fields have same width */
+#define BCM_VK_PWR_AND_THRE_FIELD_MASK	0xff
+#define BCM_VK_LOW_TEMP_THRE_SHIFT	0
+#define BCM_VK_HIGH_TEMP_THRE_SHIFT	8
+#define BCM_VK_PWR_STATE_SHIFT		16
+
+#define BAR_CARD_STATIC_INFO		0x470
+
+#define BAR_INTF_VER			0x47c
+#define BAR_INTF_VER_MAJOR_SHIFT	16
+#define BAR_INTF_VER_MASK		0xffff
+/*
+ * major and minor semantic version numbers supported
+ * Please update as required on interface changes
+ */
+#define SEMANTIC_MAJOR			1
+#define SEMANTIC_MINOR			0
+
+/*
+ * first door bell reg, ie for queue = 0.  Only need the first one, as
+ * we will use the queue number to derive the others
+ */
+#define VK_BAR0_REGSEG_DB_BASE		0x484
+#define VK_BAR0_REGSEG_DB_REG_GAP	8 /*
+					   * DB register gap,
+					   * DB1 at 0x48c and DB2 at 0x494
+					   */
+
+/* reset register and specific values */
+#define VK_BAR0_RESET_DB_NUM		3
+#define VK_BAR0_RESET_DB_SOFT		0xffffffff
+#define VK_BAR0_RESET_DB_HARD		0xfffffffd
+#define VK_BAR0_RESET_RAMPDUMP		0xa0000000
+
+#define VK_BAR0_Q_DB_BASE(q_num)	(VK_BAR0_REGSEG_DB_BASE + \
+					 ((q_num) * VK_BAR0_REGSEG_DB_REG_GAP))
+#define VK_BAR0_RESET_DB_BASE		(VK_BAR0_REGSEG_DB_BASE + \
+					 (VK_BAR0_RESET_DB_NUM * VK_BAR0_REGSEG_DB_REG_GAP))
+
+#define BAR_BOOTSRC_SELECT		0xc78
+/* BOOTSRC definitions */
+#define BOOTSRC_SOFT_ENABLE		BIT(14)
+
+/* Card OS Firmware version size */
+#define BAR_FIRMWARE_TAG_SIZE		50
+#define FIRMWARE_STATUS_PRE_INIT_DONE	0x1f
+
+/* VK MSG_ID defines */
+#define VK_MSG_ID_BITMAP_SIZE		4096
+#define VK_MSG_ID_BITMAP_MASK		(VK_MSG_ID_BITMAP_SIZE - 1)
+#define VK_MSG_ID_OVERFLOW		0xffff
+
+/*
+ * BAR1
+ */
+
+/* BAR1 message q definition */
+
+/* indicate if msgq ctrl in BAR1 is populated */
+#define VK_BAR1_MSGQ_DEF_RDY		0x60c0
+/* ready marker value for the above location, normal boot2 */
+#define VK_BAR1_MSGQ_RDY_MARKER		0xbeefcafe
+/* ready marker value for the above location, normal boot2 */
+#define VK_BAR1_DIAG_RDY_MARKER		0xdeadcafe
+/* number of msgqs in BAR1 */
+#define VK_BAR1_MSGQ_NR			0x60c4
+/* BAR1 queue control structure offset */
+#define VK_BAR1_MSGQ_CTRL_OFF		0x60c8
+
+/* BAR1 ucode and boot1 version tag */
+#define VK_BAR1_UCODE_VER_TAG		0x6170
+#define VK_BAR1_BOOT1_VER_TAG		0x61b0
+#define VK_BAR1_VER_TAG_SIZE		64
+
+/* Memory to hold the DMA buffer memory address allocated for boot2 download */
+#define VK_BAR1_DMA_BUF_OFF_HI		0x61e0
+#define VK_BAR1_DMA_BUF_OFF_LO		(VK_BAR1_DMA_BUF_OFF_HI + 4)
+#define VK_BAR1_DMA_BUF_SZ		(VK_BAR1_DMA_BUF_OFF_HI + 8)
+
+/* Scratch memory allocated on host for VK */
+#define VK_BAR1_SCRATCH_OFF_HI		0x61f0
+#define VK_BAR1_SCRATCH_OFF_LO		(VK_BAR1_SCRATCH_OFF_HI + 4)
+#define VK_BAR1_SCRATCH_SZ_ADDR		(VK_BAR1_SCRATCH_OFF_HI + 8)
+#define VK_BAR1_SCRATCH_DEF_NR_PAGES	32
+
+/* BAR1 DAUTH info */
+#define VK_BAR1_DAUTH_BASE_ADDR		0x6200
+#define VK_BAR1_DAUTH_STORE_SIZE	0x48
+#define VK_BAR1_DAUTH_VALID_SIZE	0x8
+#define VK_BAR1_DAUTH_MAX		4
+#define VK_BAR1_DAUTH_STORE_ADDR(x) \
+		(VK_BAR1_DAUTH_BASE_ADDR + \
+		 (x) * (VK_BAR1_DAUTH_STORE_SIZE + VK_BAR1_DAUTH_VALID_SIZE))
+#define VK_BAR1_DAUTH_VALID_ADDR(x) \
+		(VK_BAR1_DAUTH_STORE_ADDR(x) + VK_BAR1_DAUTH_STORE_SIZE)
+
+/* BAR1 SOTP AUTH and REVID info */
+#define VK_BAR1_SOTP_REVID_BASE_ADDR	0x6340
+#define VK_BAR1_SOTP_REVID_SIZE		0x10
+#define VK_BAR1_SOTP_REVID_MAX		2
+#define VK_BAR1_SOTP_REVID_ADDR(x) \
+		(VK_BAR1_SOTP_REVID_BASE_ADDR + (x) * VK_BAR1_SOTP_REVID_SIZE)
+
+/* VK device supports a maximum of 3 bars */
+#define MAX_BAR	3
+
+/* default number of msg blk for inband SGL */
+#define BCM_VK_DEF_IB_SGL_BLK_LEN	 16
+#define BCM_VK_IB_SGL_BLK_MAX		 24
+
+enum pci_barno {
+	BAR_0 = 0,
+	BAR_1,
+	BAR_2
+};
+
+#ifdef CONFIG_BCM_VK_TTY
+#define BCM_VK_NUM_TTY 2
+#else
+#define BCM_VK_NUM_TTY 0
+#endif
+
+struct bcm_vk_tty {
+	struct tty_port port;
+	u32 to_offset;	/* bar offset to use */
+	u32 to_size;	/* to VK buffer size */
+	u32 wr;		/* write offset shadow */
+	u32 from_offset;	/* bar offset to use */
+	u32 from_size;	/* from VK buffer size */
+	u32 rd;		/* read offset shadow */
+	pid_t pid;
+	bool irq_enabled;
+	bool is_opened;		/* tracks tty open/close */
+};
+
+/* VK device max power state, supports 3, full, reduced and low */
+#define MAX_OPP 3
+#define MAX_CARD_INFO_TAG_SIZE 64
+
+struct bcm_vk_card_info {
+	u32 version;
+	char os_tag[MAX_CARD_INFO_TAG_SIZE];
+	char cmpt_tag[MAX_CARD_INFO_TAG_SIZE];
+	u32 cpu_freq_mhz;
+	u32 cpu_scale[MAX_OPP];
+	u32 ddr_freq_mhz;
+	u32 ddr_size_MB;
+	u32 video_core_freq_mhz;
+};
+
+/* DAUTH related info */
+struct bcm_vk_dauth_key {
+	char store[VK_BAR1_DAUTH_STORE_SIZE];
+	char valid[VK_BAR1_DAUTH_VALID_SIZE];
+};
+
+struct bcm_vk_dauth_info {
+	struct bcm_vk_dauth_key keys[VK_BAR1_DAUTH_MAX];
+};
+
+/*
+ * Control structure of logging messages from the card.  This
+ * buffer is for logmsg that comes from vk
+ */
+struct bcm_vk_peer_log {
+	u32 rd_idx;
+	u32 wr_idx;
+	u32 buf_size;
+	u32 mask;
+};
+
+/* max buf size allowed */
+#define BCM_VK_PEER_LOG_BUF_MAX SZ_16K
+/* max size per line of peer log */
+#define BCM_VK_PEER_LOG_LINE_MAX  256
+
+/*
+ * single entry for processing type + utilization
+ */
+#define BCM_VK_PROC_TYPE_TAG_LEN 8
+struct bcm_vk_proc_mon_entry_t {
+	char tag[BCM_VK_PROC_TYPE_TAG_LEN];
+	u32 used;
+	u32 max; /**< max capacity */
+};
+
+/**
+ * Structure for run time utilization
+ */
+#define BCM_VK_PROC_MON_MAX 8 /* max entries supported */
+struct bcm_vk_proc_mon_info {
+	u32 num; /**< no of entries */
+	u32 entry_size; /**< per entry size */
+	struct bcm_vk_proc_mon_entry_t entries[BCM_VK_PROC_MON_MAX];
+};
+
+struct bcm_vk_hb_ctrl {
+	struct delayed_work work;
+	u32 last_uptime;
+	u32 lost_cnt;
+};
+
+struct bcm_vk_alert {
+	u16 flags;
+	u16 notfs;
+};
+
+/* some alert counters that the driver will keep track */
+struct bcm_vk_alert_cnts {
+	u16 ecc;
+	u16 uecc;
+};
+
+struct bcm_vk {
+	struct pci_dev *pdev;
+	void __iomem *bar[MAX_BAR];
+	int num_irqs;
+
+	struct bcm_vk_card_info card_info;
+	struct bcm_vk_proc_mon_info proc_mon_info;
+	struct bcm_vk_dauth_info dauth_info;
+
+	/* mutex to protect the ioctls */
+	struct mutex mutex;
+	struct miscdevice miscdev;
+	int devid; /* dev id allocated */
+
+#ifdef CONFIG_BCM_VK_TTY
+	struct tty_driver *tty_drv;
+	struct timer_list serial_timer;
+	struct bcm_vk_tty tty[BCM_VK_NUM_TTY];
+	struct workqueue_struct *tty_wq_thread;
+	struct work_struct tty_wq_work;
+#endif
+
+	/* Reference-counting to handle file operations */
+	struct kref kref;
+
+	spinlock_t msg_id_lock; /* Spinlock for msg_id */
+	u16 msg_id;
+	DECLARE_BITMAP(bmap, VK_MSG_ID_BITMAP_SIZE);
+	spinlock_t ctx_lock; /* Spinlock for component context */
+	struct bcm_vk_ctx ctx[VK_CMPT_CTX_MAX];
+	struct bcm_vk_ht_entry pid_ht[VK_PID_HT_SZ];
+	pid_t reset_pid; /* process that issue reset */
+
+	atomic_t msgq_inited; /* indicate if info has been synced with vk */
+	struct bcm_vk_msg_chan to_v_msg_chan;
+	struct bcm_vk_msg_chan to_h_msg_chan;
+
+	struct workqueue_struct *wq_thread;
+	struct work_struct wq_work; /* work queue for deferred job */
+	unsigned long wq_offload[1]; /* various flags on wq requested */
+	void *tdma_vaddr; /* test dma segment virtual addr */
+	dma_addr_t tdma_addr; /* test dma segment bus addr */
+
+	struct notifier_block panic_nb;
+	u32 ib_sgl_size; /* size allocated for inband sgl insertion */
+
+	/* heart beat mechanism control structure */
+	struct bcm_vk_hb_ctrl hb_ctrl;
+	/* house-keeping variable of error logs */
+	spinlock_t host_alert_lock; /* protection to access host_alert struct */
+	struct bcm_vk_alert host_alert;
+	struct bcm_vk_alert peer_alert; /* bits set by the card */
+	struct bcm_vk_alert_cnts alert_cnts;
+
+	/* offset of the peer log control in BAR2 */
+	u32 peerlog_off;
+	struct bcm_vk_peer_log peerlog_info; /* record of peer log info */
+	/* offset of processing monitoring info in BAR2 */
+	u32 proc_mon_off;
+};
+
+/* wq offload work items bits definitions */
+enum bcm_vk_wq_offload_flags {
+	BCM_VK_WQ_DWNLD_PEND = 0,
+	BCM_VK_WQ_DWNLD_AUTO = 1,
+	BCM_VK_WQ_NOTF_PEND  = 2,
+};
+
+/* a macro to get an individual field with mask and shift */
+#define BCM_VK_EXTRACT_FIELD(_field, _reg, _mask, _shift) \
+		(_field = (((_reg) >> (_shift)) & (_mask)))
+
+struct bcm_vk_entry {
+	const u32 mask;
+	const u32 exp_val;
+	const char *str;
+};
+
+/* alerts that could be generated from peer */
+#define BCM_VK_PEER_ERR_NUM 12
+extern struct bcm_vk_entry const bcm_vk_peer_err[BCM_VK_PEER_ERR_NUM];
+/* alerts detected by the host */
+#define BCM_VK_HOST_ERR_NUM 3
+extern struct bcm_vk_entry const bcm_vk_host_err[BCM_VK_HOST_ERR_NUM];
+
+/*
+ * check if PCIe interface is down on read.  Use it when it is
+ * certain that _val should never be all ones.
+ */
+#define BCM_VK_INTF_IS_DOWN(val) ((val) == 0xffffffff)
+
+static inline u32 vkread32(struct bcm_vk *vk, enum pci_barno bar, u64 offset)
+{
+	return readl(vk->bar[bar] + offset);
+}
+
+static inline void vkwrite32(struct bcm_vk *vk,
+			     u32 value,
+			     enum pci_barno bar,
+			     u64 offset)
+{
+	writel(value, vk->bar[bar] + offset);
+}
+
+static inline u8 vkread8(struct bcm_vk *vk, enum pci_barno bar, u64 offset)
+{
+	return readb(vk->bar[bar] + offset);
+}
+
+static inline void vkwrite8(struct bcm_vk *vk,
+			    u8 value,
+			    enum pci_barno bar,
+			    u64 offset)
+{
+	writeb(value, vk->bar[bar] + offset);
+}
+
+static inline bool bcm_vk_msgq_marker_valid(struct bcm_vk *vk)
+{
+	u32 rdy_marker = 0;
+	u32 fw_status;
+
+	fw_status = vkread32(vk, BAR_0, VK_BAR_FWSTS);
+
+	if ((fw_status & VK_FWSTS_READY) == VK_FWSTS_READY)
+		rdy_marker = vkread32(vk, BAR_1, VK_BAR1_MSGQ_DEF_RDY);
+
+	return (rdy_marker == VK_BAR1_MSGQ_RDY_MARKER);
+}
+
+int bcm_vk_open(struct inode *inode, struct file *p_file);
+ssize_t bcm_vk_read(struct file *p_file, char __user *buf, size_t count,
+		    loff_t *f_pos);
+ssize_t bcm_vk_write(struct file *p_file, const char __user *buf,
+		     size_t count, loff_t *f_pos);
+__poll_t bcm_vk_poll(struct file *p_file, struct poll_table_struct *wait);
+int bcm_vk_release(struct inode *inode, struct file *p_file);
+void bcm_vk_release_data(struct kref *kref);
+irqreturn_t bcm_vk_msgq_irqhandler(int irq, void *dev_id);
+irqreturn_t bcm_vk_notf_irqhandler(int irq, void *dev_id);
+irqreturn_t bcm_vk_tty_irqhandler(int irq, void *dev_id);
+int bcm_vk_msg_init(struct bcm_vk *vk);
+void bcm_vk_msg_remove(struct bcm_vk *vk);
+void bcm_vk_drain_msg_on_reset(struct bcm_vk *vk);
+int bcm_vk_sync_msgq(struct bcm_vk *vk, bool force_sync);
+void bcm_vk_blk_drv_access(struct bcm_vk *vk);
+s32 bcm_to_h_msg_dequeue(struct bcm_vk *vk);
+int bcm_vk_send_shutdown_msg(struct bcm_vk *vk, u32 shut_type,
+			     const pid_t pid, const u32 q_num);
+void bcm_to_v_q_doorbell(struct bcm_vk *vk, u32 q_num, u32 db_val);
+int bcm_vk_auto_load_all_images(struct bcm_vk *vk);
+void bcm_vk_hb_init(struct bcm_vk *vk);
+void bcm_vk_hb_deinit(struct bcm_vk *vk);
+void bcm_vk_handle_notf(struct bcm_vk *vk);
+bool bcm_vk_drv_access_ok(struct bcm_vk *vk);
+void bcm_vk_set_host_alert(struct bcm_vk *vk, u32 bit_mask);
+
+#ifdef CONFIG_BCM_VK_TTY
+int bcm_vk_tty_init(struct bcm_vk *vk, char *name);
+void bcm_vk_tty_exit(struct bcm_vk *vk);
+void bcm_vk_tty_terminate_tty_user(struct bcm_vk *vk);
+void bcm_vk_tty_wq_exit(struct bcm_vk *vk);
+
+static inline void bcm_vk_tty_set_irq_enabled(struct bcm_vk *vk, int index)
+{
+	vk->tty[index].irq_enabled = true;
+}
+#else
+static inline int bcm_vk_tty_init(struct bcm_vk *vk, char *name)
+{
+	return 0;
+}
+
+static inline void bcm_vk_tty_exit(struct bcm_vk *vk)
+{
+}
+
+static inline void bcm_vk_tty_terminate_tty_user(struct bcm_vk *vk)
+{
+}
+
+static inline void bcm_vk_tty_wq_exit(struct bcm_vk *vk)
+{
+}
+
+static inline void bcm_vk_tty_set_irq_enabled(struct bcm_vk *vk, int index)
+{
+}
+#endif /* CONFIG_BCM_VK_TTY */
+
+#endif

linux-7.2.3/drivers/misc/bcm-vk/bcm_vk_msg.h

@@ -0,0 +1,163 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2018-2020 Broadcom.
+ */
+
+#ifndef BCM_VK_MSG_H
+#define BCM_VK_MSG_H
+
+#include <uapi/linux/misc/bcm_vk.h>
+#include "bcm_vk_sg.h"
+
+/* Single message queue control structure */
+struct bcm_vk_msgq {
+	u16 type;	/* queue type */
+	u16 num;	/* queue number */
+	u32 start;	/* offset in BAR1 where the queue memory starts */
+
+	u32 rd_idx; /* read idx */
+	u32 wr_idx; /* write idx */
+
+	u32 size;	/*
+			 * size, which is in number of 16byte blocks,
+			 * to align with the message data structure.
+			 */
+	u32 nxt;	/*
+			 * nxt offset to the next msg queue struct.
+			 * This is to provide flexibity for alignment purposes.
+			 */
+
+/* Least significant 16 bits in below field hold doorbell register offset */
+#define DB_SHIFT 16
+
+	u32 db_offset; /* queue doorbell register offset in BAR0 */
+
+	u32 rsvd;
+};
+
+/*
+ * Structure to record static info from the msgq sync.  We keep local copy
+ * for some of these variables for both performance + checking purpose.
+ */
+struct bcm_vk_sync_qinfo {
+	void __iomem *q_start;
+	u32 q_size;
+	u32 q_mask;
+	u32 q_low;
+	u32 q_db_offset;
+};
+
+#define VK_MSGQ_MAX_NR 4 /* Maximum number of message queues */
+
+/*
+ * message block - basic unit in the message where a message's size is always
+ *		   N x sizeof(basic_block)
+ */
+struct vk_msg_blk {
+	u8 function_id;
+#define VK_FID_TRANS_BUF	5
+#define VK_FID_SHUTDOWN		8
+#define VK_FID_INIT		9
+	u8 size; /* size of the message in number of vk_msg_blk's */
+	u16 trans_id; /* transport id, queue & msg_id */
+	u32 context_id;
+#define VK_NEW_CTX		0
+	u32 cmd;
+#define VK_CMD_PLANES_MASK	0x000f /* number of planes to up/download */
+#define VK_CMD_UPLOAD		0x0400 /* memory transfer to vk */
+#define VK_CMD_DOWNLOAD		0x0500 /* memory transfer from vk */
+#define VK_CMD_MASK		0x0f00 /* command mask */
+	u32 arg;
+};
+
+/* vk_msg_blk is 16 bytes fixed */
+#define VK_MSGQ_BLK_SIZE   (sizeof(struct vk_msg_blk))
+/* shift for fast division of basic msg blk size */
+#define VK_MSGQ_BLK_SZ_SHIFT 4
+
+/* use msg_id 0 for any simplex host2vk communication */
+#define VK_SIMPLEX_MSG_ID 0
+
+/* context per session opening of sysfs */
+struct bcm_vk_ctx {
+	struct list_head node; /* use for linkage in Hash Table */
+	unsigned int idx;
+	bool in_use;
+	pid_t pid;
+	u32 hash_idx;
+	u32 q_num; /* queue number used by the stream */
+	struct miscdevice *miscdev;
+	atomic_t pend_cnt; /* number of items pending to be read from host */
+	atomic_t dma_cnt; /* any dma transaction outstanding */
+	wait_queue_head_t rd_wq;
+};
+
+/* pid hash table entry */
+struct bcm_vk_ht_entry {
+	struct list_head head;
+};
+
+#define VK_DMA_MAX_ADDRS 4 /* Max 4 DMA Addresses */
+/* structure for house keeping a single work entry */
+struct bcm_vk_wkent {
+	struct list_head node; /* for linking purpose */
+	struct bcm_vk_ctx *ctx;
+
+	/* Store up to 4 dma pointers */
+	struct bcm_vk_dma dma[VK_DMA_MAX_ADDRS];
+
+	u32 to_h_blks; /* response */
+	struct vk_msg_blk *to_h_msg;
+
+	/*
+	 * put the to_v_msg at the end so that we could simply append to_v msg
+	 * to the end of the allocated block
+	 */
+	u32 usr_msg_id;
+	u32 to_v_blks;
+	u32 seq_num;
+	struct vk_msg_blk to_v_msg[] __counted_by(to_v_blks);
+};
+
+/* queue stats counters */
+struct bcm_vk_qs_cnts {
+	u32 cnt; /* general counter, used to limit output */
+	u32 acc_sum;
+	u32 max_occ; /* max during a sampling period */
+	u32 max_abs; /* the abs max since reset */
+};
+
+/* control channel structure for either to_v or to_h communication */
+struct bcm_vk_msg_chan {
+	u32 q_nr;
+	/* Mutex to access msgq */
+	struct mutex msgq_mutex;
+	/* pointing to BAR locations */
+	struct bcm_vk_msgq __iomem *msgq[VK_MSGQ_MAX_NR];
+	/* Spinlock to access pending queue */
+	spinlock_t pendq_lock;
+	/* for temporary storing pending items, one for each queue */
+	struct list_head pendq[VK_MSGQ_MAX_NR];
+	/* static queue info from the sync */
+	struct bcm_vk_sync_qinfo sync_qinfo[VK_MSGQ_MAX_NR];
+};
+
+/* totol number of message q allowed by the driver */
+#define VK_MSGQ_PER_CHAN_MAX	3
+#define VK_MSGQ_NUM_DEFAULT	(VK_MSGQ_PER_CHAN_MAX - 1)
+
+/* total number of supported ctx, 32 ctx each for 5 components */
+#define VK_CMPT_CTX_MAX		(32 * 5)
+
+/* hash table defines to store the opened FDs */
+#define VK_PID_HT_SHIFT_BIT	7 /* 128 */
+#define VK_PID_HT_SZ		BIT(VK_PID_HT_SHIFT_BIT)
+
+/* The following are offsets of DDR info provided by the vk card */
+#define VK_BAR0_SEG_SIZE	(4 * SZ_1K) /* segment size for BAR0 */
+
+/* shutdown types supported */
+#define VK_SHUTDOWN_PID		1
+#define VK_SHUTDOWN_GRACEFUL	2
+
+#endif

linux-7.2.3/drivers/misc/bcm-vk/bcm_vk_sg.c

@@ -0,0 +1,273 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2018-2020 Broadcom.
+ */
+#include <linux/dma-mapping.h>
+#include <linux/mm.h>
+#include <linux/pagemap.h>
+#include <linux/pgtable.h>
+#include <linux/vmalloc.h>
+
+#include <asm/page.h>
+#include <linux/unaligned.h>
+
+#include <uapi/linux/misc/bcm_vk.h>
+
+#include "bcm_vk.h"
+#include "bcm_vk_msg.h"
+#include "bcm_vk_sg.h"
+
+/*
+ * Valkyrie has a hardware limitation of 16M transfer size.
+ * So limit the SGL chunks to 16M.
+ */
+#define BCM_VK_MAX_SGL_CHUNK SZ_16M
+
+static int bcm_vk_dma_alloc(struct device *dev,
+			    struct bcm_vk_dma *dma,
+			    int dir,
+			    struct _vk_data *vkdata);
+static int bcm_vk_dma_free(struct device *dev, struct bcm_vk_dma *dma);
+
+/* Uncomment to dump SGLIST */
+/* #define BCM_VK_DUMP_SGLIST */
+
+static int bcm_vk_dma_alloc(struct device *dev,
+			    struct bcm_vk_dma *dma,
+			    int direction,
+			    struct _vk_data *vkdata)
+{
+	dma_addr_t addr, sg_addr;
+	int err;
+	int i;
+	int offset;
+	u32 size;
+	u32 remaining_size;
+	u32 transfer_size;
+	u64 data;
+	unsigned long first, last;
+	struct _vk_data *sgdata;
+
+	/* Get 64-bit user address */
+	data = get_unaligned(&vkdata->address);
+
+	/* offset into first page */
+	offset = offset_in_page(data);
+
+	/* Calculate number of pages */
+	first = (data & PAGE_MASK) >> PAGE_SHIFT;
+	last  = ((data + vkdata->size - 1) & PAGE_MASK) >> PAGE_SHIFT;
+	dma->nr_pages = last - first + 1;
+
+	/* Allocate DMA pages */
+	dma->pages = kmalloc_objs(struct page *, dma->nr_pages);
+	if (!dma->pages)
+		return -ENOMEM;
+
+	dev_dbg(dev, "Alloc DMA Pages [0x%llx+0x%x => %d pages]\n",
+		data, vkdata->size, dma->nr_pages);
+
+	dma->direction = direction;
+
+	/* Get user pages into memory */
+	err = get_user_pages_fast(data & PAGE_MASK,
+				  dma->nr_pages,
+				  direction == DMA_FROM_DEVICE,
+				  dma->pages);
+	if (err != dma->nr_pages) {
+		dma->nr_pages = (err >= 0) ? err : 0;
+		dev_err(dev, "get_user_pages_fast, err=%d [%d]\n",
+			err, dma->nr_pages);
+		return err < 0 ? err : -EINVAL;
+	}
+
+	/* Max size of sg list is 1 per mapped page + fields at start */
+	dma->sglen = (dma->nr_pages * sizeof(*sgdata)) +
+		     (sizeof(u32) * SGLIST_VKDATA_START);
+
+	/* Allocate sglist */
+	dma->sglist = dma_alloc_coherent(dev,
+					 dma->sglen,
+					 &dma->handle,
+					 GFP_KERNEL);
+	if (!dma->sglist)
+		return -ENOMEM;
+
+	dma->sglist[SGLIST_NUM_SG] = 0;
+	dma->sglist[SGLIST_TOTALSIZE] = vkdata->size;
+	remaining_size = vkdata->size;
+	sgdata = (struct _vk_data *)&dma->sglist[SGLIST_VKDATA_START];
+
+	/* Map all pages into DMA */
+	size = min_t(size_t, PAGE_SIZE - offset, remaining_size);
+	remaining_size -= size;
+	sg_addr = dma_map_page(dev,
+			       dma->pages[0],
+			       offset,
+			       size,
+			       dma->direction);
+	transfer_size = size;
+	if (unlikely(dma_mapping_error(dev, sg_addr))) {
+		__free_page(dma->pages[0]);
+		return -EIO;
+	}
+
+	for (i = 1; i < dma->nr_pages; i++) {
+		size = min_t(size_t, PAGE_SIZE, remaining_size);
+		remaining_size -= size;
+		addr = dma_map_page(dev,
+				    dma->pages[i],
+				    0,
+				    size,
+				    dma->direction);
+		if (unlikely(dma_mapping_error(dev, addr))) {
+			__free_page(dma->pages[i]);
+			return -EIO;
+		}
+
+		/*
+		 * Compress SG list entry when pages are contiguous
+		 * and transfer size less or equal to BCM_VK_MAX_SGL_CHUNK
+		 */
+		if ((addr == (sg_addr + transfer_size)) &&
+		    ((transfer_size + size) <= BCM_VK_MAX_SGL_CHUNK)) {
+			/* pages are contiguous, add to same sg entry */
+			transfer_size += size;
+		} else {
+			/* pages are not contiguous, write sg entry */
+			sgdata->size = transfer_size;
+			put_unaligned(sg_addr, (u64 *)&sgdata->address);
+			dma->sglist[SGLIST_NUM_SG]++;
+
+			/* start new sg entry */
+			sgdata++;
+			sg_addr = addr;
+			transfer_size = size;
+		}
+	}
+	/* Write last sg list entry */
+	sgdata->size = transfer_size;
+	put_unaligned(sg_addr, (u64 *)&sgdata->address);
+	dma->sglist[SGLIST_NUM_SG]++;
+
+	/* Update pointers and size field to point to sglist */
+	put_unaligned((u64)dma->handle, &vkdata->address);
+	vkdata->size = (dma->sglist[SGLIST_NUM_SG] * sizeof(*sgdata)) +
+		       (sizeof(u32) * SGLIST_VKDATA_START);
+
+#ifdef BCM_VK_DUMP_SGLIST
+	dev_dbg(dev,
+		"sgl 0x%llx handle 0x%llx, sglen: 0x%x sgsize: 0x%x\n",
+		(u64)dma->sglist,
+		dma->handle,
+		dma->sglen,
+		vkdata->size);
+	for (i = 0; i < vkdata->size / sizeof(u32); i++)
+		dev_dbg(dev, "i:0x%x 0x%x\n", i, dma->sglist[i]);
+#endif
+
+	return 0;
+}
+
+int bcm_vk_sg_alloc(struct device *dev,
+		    struct bcm_vk_dma *dma,
+		    int dir,
+		    struct _vk_data *vkdata,
+		    int num)
+{
+	int i;
+	int rc = -EINVAL;
+
+	/* Convert user addresses to DMA SG List */
+	for (i = 0; i < num; i++) {
+		if (vkdata[i].size && vkdata[i].address) {
+			/*
+			 * If both size and address are non-zero
+			 * then DMA alloc.
+			 */
+			rc = bcm_vk_dma_alloc(dev,
+					      &dma[i],
+					      dir,
+					      &vkdata[i]);
+		} else if (vkdata[i].size ||
+			   vkdata[i].address) {
+			/*
+			 * If one of size and address are zero
+			 * there is a problem.
+			 */
+			dev_err(dev,
+				"Invalid vkdata %x 0x%x 0x%llx\n",
+				i, vkdata[i].size, vkdata[i].address);
+			rc = -EINVAL;
+		} else {
+			/*
+			 * If size and address are both zero
+			 * don't convert, but return success.
+			 */
+			rc = 0;
+		}
+
+		if (rc)
+			goto fail_alloc;
+	}
+	return rc;
+
+fail_alloc:
+	while (i > 0) {
+		i--;
+		if (dma[i].sglist)
+			bcm_vk_dma_free(dev, &dma[i]);
+	}
+	return rc;
+}
+
+static int bcm_vk_dma_free(struct device *dev, struct bcm_vk_dma *dma)
+{
+	dma_addr_t addr;
+	int i;
+	int num_sg;
+	u32 size;
+	struct _vk_data *vkdata;
+
+	dev_dbg(dev, "free sglist=%p sglen=0x%x\n", dma->sglist, dma->sglen);
+
+	/* Unmap all pages in the sglist */
+	num_sg = dma->sglist[SGLIST_NUM_SG];
+	vkdata = (struct _vk_data *)&dma->sglist[SGLIST_VKDATA_START];
+	for (i = 0; i < num_sg; i++) {
+		size = vkdata[i].size;
+		addr = get_unaligned(&vkdata[i].address);
+
+		dma_unmap_page(dev, addr, size, dma->direction);
+	}
+
+	/* Free allocated sglist */
+	dma_free_coherent(dev, dma->sglen, dma->sglist, dma->handle);
+
+	/* Release lock on all pages */
+	for (i = 0; i < dma->nr_pages; i++)
+		put_page(dma->pages[i]);
+
+	/* Free allocated dma pages */
+	kfree(dma->pages);
+	dma->sglist = NULL;
+
+	return 0;
+}
+
+int bcm_vk_sg_free(struct device *dev, struct bcm_vk_dma *dma, int num,
+		   int *proc_cnt)
+{
+	int i;
+
+	*proc_cnt = 0;
+	/* Unmap and free all pages and sglists */
+	for (i = 0; i < num; i++) {
+		if (dma[i].sglist) {
+			bcm_vk_dma_free(dev, &dma[i]);
+			*proc_cnt += 1;
+		}
+	}
+
+	return 0;
+}

linux-7.2.3/drivers/misc/bcm-vk/bcm_vk_sg.h

@@ -0,0 +1,61 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2018-2020 Broadcom.
+ */
+
+#ifndef BCM_VK_SG_H
+#define BCM_VK_SG_H
+
+#include <linux/dma-mapping.h>
+
+struct bcm_vk_dma {
+	/* for userland buffer */
+	struct page **pages;
+	int nr_pages;
+
+	/* common */
+	dma_addr_t handle;
+	/*
+	 * sglist is of the following LE format
+	 * [U32] num_sg  = number of sg addresses (N)
+	 * [U32] totalsize = totalsize of data being transferred in sglist
+	 * [U32] size[0] = size of data in address0
+	 * [U32] addr_l[0] = lower 32-bits of address0
+	 * [U32] addr_h[0] = higher 32-bits of address0
+	 * ..
+	 * [U32] size[N-1] = size of data in addressN-1
+	 * [U32] addr_l[N-1] = lower 32-bits of addressN-1
+	 * [U32] addr_h[N-1] = higher 32-bits of addressN-1
+	 */
+	u32 *sglist;
+#define SGLIST_NUM_SG		0
+#define SGLIST_TOTALSIZE	1
+#define SGLIST_VKDATA_START	2
+
+	int sglen; /* Length (bytes) of sglist */
+	int direction;
+};
+
+struct _vk_data {
+	u32 size;    /* data size in bytes */
+	u64 address; /* Pointer to data     */
+} __packed;
+
+/*
+ * Scatter-gather DMA buffer API.
+ *
+ * These functions provide a simple way to create a page list and a
+ * scatter-gather list from userspace address and map the memory
+ * for DMA operation.
+ */
+int bcm_vk_sg_alloc(struct device *dev,
+		    struct bcm_vk_dma *dma,
+		    int dir,
+		    struct _vk_data *vkdata,
+		    int num);
+
+int bcm_vk_sg_free(struct device *dev, struct bcm_vk_dma *dma, int num,
+		   int *proc_cnt);
+
+#endif
+

linux-7.2.3/drivers/misc/bcm-vk/bcm_vk_tty.c

@@ -0,0 +1,338 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2018-2020 Broadcom.
+ */
+
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/tty_flip.h>
+
+#include "bcm_vk.h"
+
+/* TTYVK base offset is 0x30000 into BAR1 */
+#define BAR1_TTYVK_BASE_OFFSET	0x300000
+/* Each TTYVK channel (TO or FROM) is 0x10000 */
+#define BAR1_TTYVK_CHAN_OFFSET	0x100000
+/* Each TTYVK channel has TO and FROM, hence the * 2 */
+#define BAR1_TTYVK_BASE(index)	(BAR1_TTYVK_BASE_OFFSET + \
+				 ((index) * BAR1_TTYVK_CHAN_OFFSET * 2))
+/* TO TTYVK channel base comes before FROM for each index */
+#define TO_TTYK_BASE(index)	BAR1_TTYVK_BASE(index)
+#define FROM_TTYK_BASE(index)	(BAR1_TTYVK_BASE(index) + \
+				 BAR1_TTYVK_CHAN_OFFSET)
+
+struct bcm_vk_tty_chan {
+	u32 reserved;
+	u32 size;
+	u32 wr;
+	u32 rd;
+	u32 *data;
+};
+
+#define VK_BAR_CHAN(v, DIR, e)	((v)->DIR##_offset \
+				 + offsetof(struct bcm_vk_tty_chan, e))
+#define VK_BAR_CHAN_SIZE(v, DIR)	VK_BAR_CHAN(v, DIR, size)
+#define VK_BAR_CHAN_WR(v, DIR)		VK_BAR_CHAN(v, DIR, wr)
+#define VK_BAR_CHAN_RD(v, DIR)		VK_BAR_CHAN(v, DIR, rd)
+#define VK_BAR_CHAN_DATA(v, DIR, off)	(VK_BAR_CHAN(v, DIR, data) + (off))
+
+#define VK_BAR0_REGSEG_TTY_DB_OFFSET	0x86c
+
+/* Poll every 1/10 of second - temp hack till we use MSI interrupt */
+#define SERIAL_TIMER_VALUE (HZ / 10)
+
+static void bcm_vk_tty_poll(struct timer_list *t)
+{
+	struct bcm_vk *vk = timer_container_of(vk, t, serial_timer);
+
+	queue_work(vk->tty_wq_thread, &vk->tty_wq_work);
+	mod_timer(&vk->serial_timer, jiffies + SERIAL_TIMER_VALUE);
+}
+
+irqreturn_t bcm_vk_tty_irqhandler(int irq, void *dev_id)
+{
+	struct bcm_vk *vk = dev_id;
+
+	queue_work(vk->tty_wq_thread, &vk->tty_wq_work);
+
+	return IRQ_HANDLED;
+}
+
+static void bcm_vk_tty_wq_handler(struct work_struct *work)
+{
+	struct bcm_vk *vk = container_of(work, struct bcm_vk, tty_wq_work);
+	struct bcm_vk_tty *vktty;
+	int card_status;
+	int count;
+	int i;
+	int wr;
+	u8 c;
+
+	card_status = vkread32(vk, BAR_0, BAR_CARD_STATUS);
+	if (BCM_VK_INTF_IS_DOWN(card_status))
+		return;
+
+	for (i = 0; i < BCM_VK_NUM_TTY; i++) {
+		count = 0;
+		/* Check the card status that the tty channel is ready */
+		if ((card_status & BIT(i)) == 0)
+			continue;
+
+		vktty = &vk->tty[i];
+
+		/* Don't increment read index if tty app is closed */
+		if (!vktty->is_opened)
+			continue;
+
+		/* Fetch the wr offset in buffer from VK */
+		wr = vkread32(vk, BAR_1, VK_BAR_CHAN_WR(vktty, from));
+
+		/* safe to ignore until bar read gives proper size */
+		if (vktty->from_size == 0)
+			continue;
+
+		if (wr >= vktty->from_size) {
+			dev_err(&vk->pdev->dev,
+				"ERROR: wq handler ttyVK%d wr:0x%x > 0x%x\n",
+				i, wr, vktty->from_size);
+			/* Need to signal and close device in this case */
+			continue;
+		}
+
+		/*
+		 * Simple read of circular buffer and
+		 * insert into tty flip buffer
+		 */
+		while (vk->tty[i].rd != wr) {
+			c = vkread8(vk, BAR_1,
+				    VK_BAR_CHAN_DATA(vktty, from, vktty->rd));
+			vktty->rd++;
+			if (vktty->rd >= vktty->from_size)
+				vktty->rd = 0;
+			tty_insert_flip_char(&vktty->port, c, TTY_NORMAL);
+			count++;
+		}
+
+		if (count) {
+			tty_flip_buffer_push(&vktty->port);
+
+			/* Update read offset from shadow register to card */
+			vkwrite32(vk, vktty->rd, BAR_1,
+				  VK_BAR_CHAN_RD(vktty, from));
+		}
+	}
+}
+
+static int bcm_vk_tty_open(struct tty_struct *tty, struct file *file)
+{
+	int card_status;
+	struct bcm_vk *vk;
+	struct bcm_vk_tty *vktty;
+	int index;
+
+	/* initialize the pointer in case something fails */
+	tty->driver_data = NULL;
+
+	vk = (struct bcm_vk *)dev_get_drvdata(tty->dev);
+	index = tty->index;
+
+	if (index >= BCM_VK_NUM_TTY)
+		return -EINVAL;
+
+	vktty = &vk->tty[index];
+
+	vktty->pid = task_pid_nr(current);
+	vktty->to_offset = TO_TTYK_BASE(index);
+	vktty->from_offset = FROM_TTYK_BASE(index);
+
+	/* Do not allow tty device to be opened if tty on card not ready */
+	card_status = vkread32(vk, BAR_0, BAR_CARD_STATUS);
+	if (BCM_VK_INTF_IS_DOWN(card_status) || ((card_status & BIT(index)) == 0))
+		return -EBUSY;
+
+	/*
+	 * Get shadow registers of the buffer sizes and the "to" write offset
+	 * and "from" read offset
+	 */
+	vktty->to_size = vkread32(vk, BAR_1, VK_BAR_CHAN_SIZE(vktty, to));
+	vktty->wr = vkread32(vk, BAR_1,  VK_BAR_CHAN_WR(vktty, to));
+	vktty->from_size = vkread32(vk, BAR_1, VK_BAR_CHAN_SIZE(vktty, from));
+	vktty->rd = vkread32(vk, BAR_1,  VK_BAR_CHAN_RD(vktty, from));
+	vktty->is_opened = true;
+
+	if (tty->count == 1 && !vktty->irq_enabled) {
+		timer_setup(&vk->serial_timer, bcm_vk_tty_poll, 0);
+		mod_timer(&vk->serial_timer, jiffies + SERIAL_TIMER_VALUE);
+	}
+	return 0;
+}
+
+static void bcm_vk_tty_close(struct tty_struct *tty, struct file *file)
+{
+	struct bcm_vk *vk = dev_get_drvdata(tty->dev);
+
+	if (tty->index >= BCM_VK_NUM_TTY)
+		return;
+
+	vk->tty[tty->index].is_opened = false;
+
+	if (tty->count == 1)
+		timer_delete_sync(&vk->serial_timer);
+}
+
+static void bcm_vk_tty_doorbell(struct bcm_vk *vk, u32 db_val)
+{
+	vkwrite32(vk, db_val, BAR_0,
+		  VK_BAR0_REGSEG_DB_BASE + VK_BAR0_REGSEG_TTY_DB_OFFSET);
+}
+
+static ssize_t bcm_vk_tty_write(struct tty_struct *tty, const u8 *buffer,
+				size_t count)
+{
+	int index;
+	struct bcm_vk *vk;
+	struct bcm_vk_tty *vktty;
+	size_t i;
+
+	index = tty->index;
+	vk = dev_get_drvdata(tty->dev);
+	vktty = &vk->tty[index];
+
+	/* Simple write each byte to circular buffer */
+	for (i = 0; i < count; i++) {
+		vkwrite8(vk, buffer[i], BAR_1,
+			 VK_BAR_CHAN_DATA(vktty, to, vktty->wr));
+		vktty->wr++;
+		if (vktty->wr >= vktty->to_size)
+			vktty->wr = 0;
+	}
+	/* Update write offset from shadow register to card */
+	vkwrite32(vk, vktty->wr, BAR_1, VK_BAR_CHAN_WR(vktty, to));
+	bcm_vk_tty_doorbell(vk, 0);
+
+	return count;
+}
+
+static unsigned int bcm_vk_tty_write_room(struct tty_struct *tty)
+{
+	struct bcm_vk *vk = dev_get_drvdata(tty->dev);
+
+	return vk->tty[tty->index].to_size - 1;
+}
+
+static const struct tty_operations serial_ops = {
+	.open = bcm_vk_tty_open,
+	.close = bcm_vk_tty_close,
+	.write = bcm_vk_tty_write,
+	.write_room = bcm_vk_tty_write_room,
+};
+
+int bcm_vk_tty_init(struct bcm_vk *vk, char *name)
+{
+	int i;
+	int err;
+	struct tty_driver *tty_drv;
+	struct device *dev = &vk->pdev->dev;
+
+	tty_drv = tty_alloc_driver
+				(BCM_VK_NUM_TTY,
+				 TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV);
+	if (IS_ERR(tty_drv))
+		return PTR_ERR(tty_drv);
+
+	/* Save struct tty_driver for uninstalling the device */
+	vk->tty_drv = tty_drv;
+
+	/* initialize the tty driver */
+	tty_drv->driver_name = KBUILD_MODNAME;
+	tty_drv->name = kstrdup(name, GFP_KERNEL);
+	if (!tty_drv->name) {
+		err = -ENOMEM;
+		goto err_tty_driver_kref_put;
+	}
+	tty_drv->type = TTY_DRIVER_TYPE_SERIAL;
+	tty_drv->subtype = SERIAL_TYPE_NORMAL;
+	tty_drv->init_termios = tty_std_termios;
+	tty_set_operations(tty_drv, &serial_ops);
+
+	/* register the tty driver */
+	err = tty_register_driver(tty_drv);
+	if (err) {
+		dev_err(dev, "tty_register_driver failed\n");
+		goto err_kfree_tty_name;
+	}
+
+	for (i = 0; i < BCM_VK_NUM_TTY; i++) {
+		struct device *tty_dev;
+
+		tty_port_init(&vk->tty[i].port);
+		tty_dev = tty_port_register_device_attr(&vk->tty[i].port,
+							tty_drv, i, dev, vk,
+							NULL);
+		if (IS_ERR(tty_dev)) {
+			err = PTR_ERR(tty_dev);
+			goto unwind;
+		}
+		vk->tty[i].is_opened = false;
+	}
+
+	INIT_WORK(&vk->tty_wq_work, bcm_vk_tty_wq_handler);
+	vk->tty_wq_thread = create_singlethread_workqueue("tty");
+	if (!vk->tty_wq_thread) {
+		dev_err(dev, "Fail to create tty workqueue thread\n");
+		err = -ENOMEM;
+		goto unwind;
+	}
+	return 0;
+
+unwind:
+	while (--i >= 0)
+		tty_port_unregister_device(&vk->tty[i].port, tty_drv, i);
+	tty_unregister_driver(tty_drv);
+
+err_kfree_tty_name:
+	kfree(tty_drv->name);
+	tty_drv->name = NULL;
+
+err_tty_driver_kref_put:
+	tty_driver_kref_put(tty_drv);
+
+	return err;
+}
+
+void bcm_vk_tty_exit(struct bcm_vk *vk)
+{
+	int i;
+
+	timer_delete_sync(&vk->serial_timer);
+	for (i = 0; i < BCM_VK_NUM_TTY; ++i) {
+		tty_port_unregister_device(&vk->tty[i].port,
+					   vk->tty_drv,
+					   i);
+		tty_port_destroy(&vk->tty[i].port);
+	}
+	tty_unregister_driver(vk->tty_drv);
+
+	kfree(vk->tty_drv->name);
+	vk->tty_drv->name = NULL;
+
+	tty_driver_kref_put(vk->tty_drv);
+}
+
+void bcm_vk_tty_terminate_tty_user(struct bcm_vk *vk)
+{
+	struct bcm_vk_tty *vktty;
+	int i;
+
+	for (i = 0; i < BCM_VK_NUM_TTY; ++i) {
+		vktty = &vk->tty[i];
+		if (vktty->pid)
+			kill_pid(find_vpid(vktty->pid), SIGKILL, 1);
+	}
+}
+
+void bcm_vk_tty_wq_exit(struct bcm_vk *vk)
+{
+	cancel_work_sync(&vk->tty_wq_work);
+	destroy_workqueue(vk->tty_wq_thread);
+}