Re: [PATCH v14 2/4] CMDQ: Mediatek CMDQ driver
From: Jassi Brar
Date: Thu Sep 22 2016 - 04:17:19 EST
On Mon, Sep 5, 2016 at 7:14 AM, HS Liao <hs.liao@xxxxxxxxxxxx> wrote:
> This patch is first version of Mediatek Command Queue(CMDQ) driver. The
> CMDQ is used to help write registers with critical time limitation,
> such as updating display configuration during the vblank. It controls
> Global Command Engine (GCE) hardware to achieve this requirement.
> Currently, CMDQ only supports display related hardwares, but we expect
> it can be extended to other hardwares for future requirements.
>
> Signed-off-by: HS Liao <hs.liao@xxxxxxxxxxxx>
> Signed-off-by: CK Hu <ck.hu@xxxxxxxxxxxx>
> ---
> drivers/mailbox/Kconfig | 10 +
> drivers/mailbox/Makefile | 2 +
> drivers/mailbox/mtk-cmdq.c | 927 +++++++++++++++++++++++++++++++++++++++
> include/linux/mailbox/mtk-cmdq.h | 180 ++++++++
> 4 files changed, 1119 insertions(+)
> create mode 100644 drivers/mailbox/mtk-cmdq.c
> create mode 100644 include/linux/mailbox/mtk-cmdq.h
>
> diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig
> index 97c3729..c987382 100644
> --- a/drivers/mailbox/Kconfig
> +++ b/drivers/mailbox/Kconfig
> @@ -132,4 +132,14 @@ config BCM_PDC_MBOX
> Mailbox implementation for the Broadcom PDC ring manager,
> which provides access to various offload engines on Broadcom
> SoCs. Say Y here if you want to use the Broadcom PDC.
> +
> +config MTK_CMDQ
> + bool "MediaTek CMDQ Support"
> + depends on ARM64 && ( ARCH_MEDIATEK || COMPILE_TEST )
> + select MTK_INFRACFG
> + help
> + Say yes here to add support for the MediaTek Command Queue (CMDQ)
> + driver. The CMDQ is used to help read/write registers with critical
> + time limitation, such as updating display configuration during the
> + vblank.
> endif
> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile
> index 66c38e3..eb5e04e 100644
> --- a/drivers/mailbox/Makefile
> +++ b/drivers/mailbox/Makefile
> @@ -27,3 +27,5 @@ obj-$(CONFIG_XGENE_SLIMPRO_MBOX) += mailbox-xgene-slimpro.o
> obj-$(CONFIG_HI6220_MBOX) += hi6220-mailbox.o
>
> obj-$(CONFIG_BCM_PDC_MBOX) += bcm-pdc-mailbox.o
> +
> +obj-$(CONFIG_MTK_CMDQ) += mtk-cmdq.o
> diff --git a/drivers/mailbox/mtk-cmdq.c b/drivers/mailbox/mtk-cmdq.c
> new file mode 100644
> index 0000000..daf5561
> --- /dev/null
> +++ b/drivers/mailbox/mtk-cmdq.c
> @@ -0,0 +1,927 @@
> +/*
> + * Copyright (c) 2015 MediaTek Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/bitops.h>
> +#include <linux/clk.h>
> +#include <linux/clk-provider.h>
> +#include <linux/completion.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/errno.h>
> +#include <linux/interrupt.h>
> +#include <linux/iopoll.h>
> +#include <linux/kernel.h>
> +#include <linux/kthread.h>
> +#include <linux/mailbox/mtk-cmdq.h>
> +#include <linux/mutex.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +#include <linux/slab.h>
> +#include <linux/spinlock.h>
> +#include <linux/suspend.h>
> +#include <linux/timer.h>
> +
> +#define CMDQ_THR_MAX_COUNT 3 /* main, sub, general(misc) */
> +#define CMDQ_INST_SIZE 8 /* instruction is 64-bit */
> +#define CMDQ_TIMEOUT_MS 1000
> +#define CMDQ_IRQ_MASK 0xffff
> +#define CMDQ_NUM_CMD(t) (t->cmd_buf_size / CMDQ_INST_SIZE)
> +
> +#define CMDQ_CURR_IRQ_STATUS 0x10
> +#define CMDQ_THR_SLOT_CYCLES 0x30
> +
> +#define CMDQ_THR_BASE 0x100
> +#define CMDQ_THR_SIZE 0x80
> +#define CMDQ_THR_WARM_RESET 0x00
> +#define CMDQ_THR_ENABLE_TASK 0x04
> +#define CMDQ_THR_SUSPEND_TASK 0x08
> +#define CMDQ_THR_CURR_STATUS 0x0c
> +#define CMDQ_THR_IRQ_STATUS 0x10
> +#define CMDQ_THR_IRQ_ENABLE 0x14
> +#define CMDQ_THR_CURR_ADDR 0x20
> +#define CMDQ_THR_END_ADDR 0x24
> +#define CMDQ_THR_WAIT_TOKEN 0x30
> +
> +#define CMDQ_THR_ENABLED 0x1
> +#define CMDQ_THR_DISABLED 0x0
> +#define CMDQ_THR_SUSPEND 0x1
> +#define CMDQ_THR_RESUME 0x0
> +#define CMDQ_THR_STATUS_SUSPENDED BIT(1)
> +#define CMDQ_THR_DO_WARM_RESET BIT(0)
> +#define CMDQ_THR_ACTIVE_SLOT_CYCLES 0x3200
> +#define CMDQ_THR_IRQ_DONE 0x1
> +#define CMDQ_THR_IRQ_ERROR 0x12
> +#define CMDQ_THR_IRQ_EN (CMDQ_THR_IRQ_ERROR | CMDQ_THR_IRQ_DONE)
> +#define CMDQ_THR_IS_WAITING BIT(31)
> +
> +#define CMDQ_OP_CODE_SHIFT 24
> +#define CMDQ_SUBSYS_SHIFT 16
> +
> +#define CMDQ_ARG_A_WRITE_MASK 0xffff
> +#define CMDQ_OP_CODE_MASK (0xff << CMDQ_OP_CODE_SHIFT)
> +
> +#define CMDQ_WRITE_ENABLE_MASK BIT(0)
> +#define CMDQ_JUMP_BY_OFFSET 0x10000000
> +#define CMDQ_JUMP_BY_PA 0x10000001
> +#define CMDQ_JUMP_PASS CMDQ_INST_SIZE
> +#define CMDQ_WFE_UPDATE BIT(31)
> +#define CMDQ_WFE_WAIT BIT(15)
> +#define CMDQ_WFE_WAIT_VALUE 0x1
> +#define CMDQ_EOC_IRQ_EN BIT(0)
> +
> +/*
> + * CMDQ_CODE_MASK:
> + * set write mask
> + * format: op mask
> + * CMDQ_CODE_WRITE:
> + * write value into target register
> + * format: op subsys address value
> + * CMDQ_CODE_JUMP:
> + * jump by offset
> + * format: op offset
> + * CMDQ_CODE_WFE:
> + * wait for event and clear
> + * it is just clear if no wait
> + * format: [wait] op event update:1 to_wait:1 wait:1
> + * [clear] op event update:1 to_wait:0 wait:0
> + * CMDQ_CODE_EOC:
> + * end of command
> + * format: op irq_flag
> + */
> +enum cmdq_code {
> + CMDQ_CODE_MASK = 0x02,
> + CMDQ_CODE_WRITE = 0x04,
> + CMDQ_CODE_JUMP = 0x10,
> + CMDQ_CODE_WFE = 0x20,
> + CMDQ_CODE_EOC = 0x40,
> +};
> +
> +struct cmdq_task_cb {
> + cmdq_async_flush_cb cb;
> + void *data;
> +};
> +
> +struct cmdq_thread {
> + struct mbox_chan *chan;
> + void __iomem *base;
> + struct list_head task_busy_list;
> + struct timer_list timeout;
> + bool atomic_exec;
> +};
> +
> +struct cmdq_task {
> + struct cmdq *cmdq;
> + struct list_head list_entry;
> + void *va_base;
> + dma_addr_t pa_base;
> + size_t cmd_buf_size; /* command occupied size */
> + size_t buf_size; /* real buffer size */
> + bool finalized;
> + struct cmdq_thread *thread;
> + struct cmdq_task_cb cb;
> +};
> +
> +struct cmdq {
> + struct mbox_controller mbox;
> + void __iomem *base;
> + u32 irq;
> + struct cmdq_thread thread[CMDQ_THR_MAX_COUNT];
> + struct mutex task_mutex;
> + struct clk *clock;
> + bool suspended;
> +};
> +
> +struct cmdq_subsys {
> + u32 base;
> + int id;
> +};
> +
> +static const struct cmdq_subsys gce_subsys[] = {
> + {0x1400, 1},
> + {0x1401, 2},
> + {0x1402, 3},
> +};
> +
> +static int cmdq_subsys_base_to_id(u32 base)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(gce_subsys); i++)
> + if (gce_subsys[i].base == base)
> + return gce_subsys[i].id;
> + return -EFAULT;
> +}
> +
> +static int cmdq_thread_suspend(struct cmdq *cmdq, struct cmdq_thread *thread)
> +{
> + u32 status;
> +
> + writel(CMDQ_THR_SUSPEND, thread->base + CMDQ_THR_SUSPEND_TASK);
> +
> + /* If already disabled, treat as suspended successful. */
> + if (!(readl(thread->base + CMDQ_THR_ENABLE_TASK) & CMDQ_THR_ENABLED))
> + return 0;
> +
> + if (readl_poll_timeout_atomic(thread->base + CMDQ_THR_CURR_STATUS,
> + status, status & CMDQ_THR_STATUS_SUSPENDED, 0, 10)) {
> + dev_err(cmdq->mbox.dev, "suspend GCE thread 0x%x failed\n",
> + (u32)(thread->base - cmdq->base));
> + return -EFAULT;
> + }
> +
> + return 0;
> +}
> +
> +static void cmdq_thread_resume(struct cmdq_thread *thread)
> +{
> + writel(CMDQ_THR_RESUME, thread->base + CMDQ_THR_SUSPEND_TASK);
> +}
> +
> +static int cmdq_thread_reset(struct cmdq *cmdq, struct cmdq_thread *thread)
> +{
> + u32 warm_reset;
> +
> + writel(CMDQ_THR_DO_WARM_RESET, thread->base + CMDQ_THR_WARM_RESET);
> + if (readl_poll_timeout_atomic(thread->base + CMDQ_THR_WARM_RESET,
> + warm_reset, !(warm_reset & CMDQ_THR_DO_WARM_RESET),
> + 0, 10)) {
> + dev_err(cmdq->mbox.dev, "reset GCE thread 0x%x failed\n",
> + (u32)(thread->base - cmdq->base));
> + return -EFAULT;
> + }
> + writel(CMDQ_THR_ACTIVE_SLOT_CYCLES, cmdq->base + CMDQ_THR_SLOT_CYCLES);
> + return 0;
> +}
> +
> +static void cmdq_thread_disable(struct cmdq *cmdq, struct cmdq_thread *thread)
> +{
> + cmdq_thread_reset(cmdq, thread);
> + writel(CMDQ_THR_DISABLED, thread->base + CMDQ_THR_ENABLE_TASK);
> +}
> +
> +/* notify GCE to re-fetch commands by setting GCE thread PC */
> +static void cmdq_thread_invalidate_fetched_data(struct cmdq_thread *thread)
> +{
> + writel(readl(thread->base + CMDQ_THR_CURR_ADDR),
> + thread->base + CMDQ_THR_CURR_ADDR);
> +}
> +
> +static void cmdq_task_insert_into_thread(struct cmdq_task *task)
> +{
> + struct device *dev = task->cmdq->mbox.dev;
> + struct cmdq_thread *thread = task->thread;
> + struct cmdq_task *prev_task = list_last_entry(
> + &thread->task_busy_list, typeof(*task), list_entry);
> + u64 *prev_task_base = prev_task->va_base;
> +
> + /* let previous task jump to this task */
> + dma_sync_single_for_cpu(dev, prev_task->pa_base,
> + prev_task->cmd_buf_size, DMA_TO_DEVICE);
> + prev_task_base[CMDQ_NUM_CMD(prev_task) - 1] =
> + (u64)CMDQ_JUMP_BY_PA << 32 | task->pa_base;
> + dma_sync_single_for_device(dev, prev_task->pa_base,
> + prev_task->cmd_buf_size, DMA_TO_DEVICE);
> +
> + cmdq_thread_invalidate_fetched_data(thread);
> +}
> +
> +static bool cmdq_command_is_wfe(u64 cmd)
> +{
> + u64 wfe_option = CMDQ_WFE_UPDATE | CMDQ_WFE_WAIT | CMDQ_WFE_WAIT_VALUE;
> + u64 wfe_op = (u64)(CMDQ_CODE_WFE << CMDQ_OP_CODE_SHIFT) << 32;
> + u64 wfe_mask = (u64)CMDQ_OP_CODE_MASK << 32 | 0xffffffff;
> +
> + return ((cmd & wfe_mask) == (wfe_op | wfe_option));
> +}
> +
> +/* we assume tasks in the same display GCE thread are waiting the same event. */
> +static void cmdq_task_remove_wfe(struct cmdq_task *task)
> +{
> + struct device *dev = task->cmdq->mbox.dev;
> + u64 *base = task->va_base;
> + int i;
> +
> + dma_sync_single_for_cpu(dev, task->pa_base, task->cmd_buf_size,
> + DMA_TO_DEVICE);
> + for (i = 0; i < CMDQ_NUM_CMD(task); i++)
> + if (cmdq_command_is_wfe(base[i]))
> + base[i] = (u64)CMDQ_JUMP_BY_OFFSET << 32 |
> + CMDQ_JUMP_PASS;
> + dma_sync_single_for_device(dev, task->pa_base, task->cmd_buf_size,
> + DMA_TO_DEVICE);
> +}
> +
> +static bool cmdq_thread_is_in_wfe(struct cmdq_thread *thread)
> +{
> + return readl(thread->base + CMDQ_THR_WAIT_TOKEN) & CMDQ_THR_IS_WAITING;
> +}
> +
> +static void cmdq_thread_wait_end(struct cmdq_thread *thread,
> + unsigned long end_pa)
> +{
> + struct device *dev = thread->chan->mbox->dev;
> + unsigned long curr_pa;
> +
> + if (readl_poll_timeout_atomic(thread->base + CMDQ_THR_CURR_ADDR,
> + curr_pa, curr_pa == end_pa, 1, 20))
> + dev_err(dev, "GCE thread cannot run to end.\n");
> +}
> +
> +static void cmdq_task_exec(struct cmdq_task *task, struct cmdq_thread *thread)
> +{
> + struct cmdq *cmdq = task->cmdq;
> + unsigned long curr_pa, end_pa;
> +
> + task->thread = thread;
> + if (list_empty(&thread->task_busy_list)) {
> + WARN_ON(clk_enable(cmdq->clock) < 0);
> + WARN_ON(cmdq_thread_reset(cmdq, thread) < 0);
> +
> + writel(task->pa_base, thread->base + CMDQ_THR_CURR_ADDR);
> + writel(task->pa_base + task->cmd_buf_size,
> + thread->base + CMDQ_THR_END_ADDR);
> + writel(CMDQ_THR_IRQ_EN, thread->base + CMDQ_THR_IRQ_ENABLE);
> + writel(CMDQ_THR_ENABLED, thread->base + CMDQ_THR_ENABLE_TASK);
> +
> + mod_timer(&thread->timeout,
> + jiffies + msecs_to_jiffies(CMDQ_TIMEOUT_MS));
> + } else {
> + WARN_ON(cmdq_thread_suspend(cmdq, thread) < 0);
> + curr_pa = readl(thread->base + CMDQ_THR_CURR_ADDR);
> + end_pa = readl(thread->base + CMDQ_THR_END_ADDR);
> +
> + /*
> + * Atomic execution should remove the following wfe, i.e. only
> + * wait event at first task, and prevent to pause when running.
> + */
> + if (thread->atomic_exec) {
> + /* GCE is executing if command is not WFE */
> + if (!cmdq_thread_is_in_wfe(thread)) {
> + cmdq_thread_resume(thread);
> + cmdq_thread_wait_end(thread, end_pa);
> + WARN_ON(cmdq_thread_suspend(cmdq, thread) < 0);
> + /* set to this task directly */
> + writel(task->pa_base,
> + thread->base + CMDQ_THR_CURR_ADDR);
> + } else {
> + cmdq_task_insert_into_thread(task);
> + cmdq_task_remove_wfe(task);
> + smp_mb(); /* modify jump before enable thread */
> + }
> + } else {
> + /* check boundary */
> + if (curr_pa == end_pa - CMDQ_INST_SIZE ||
> + curr_pa == end_pa) {
> + /* set to this task directly */
> + writel(task->pa_base,
> + thread->base + CMDQ_THR_CURR_ADDR);
> + } else {
> + cmdq_task_insert_into_thread(task);
> + smp_mb(); /* modify jump before enable thread */
> + }
> + }
> + writel(task->pa_base + task->cmd_buf_size,
> + thread->base + CMDQ_THR_END_ADDR);
> + cmdq_thread_resume(thread);
> + }
> + list_move_tail(&task->list_entry, &thread->task_busy_list);
> +}
> +
> +static void cmdq_task_exec_done(struct cmdq_task *task, bool err)
> +{
> + struct device *dev = task->cmdq->mbox.dev;
> + struct cmdq_cb_data cmdq_cb_data;
> +
> + if (task->cb.cb) {
> + cmdq_cb_data.err = err;
> + cmdq_cb_data.data = task->cb.data;
> + task->cb.cb(cmdq_cb_data);
> + }
> + list_del(&task->list_entry);
> + dma_unmap_single(dev, task->pa_base, task->cmd_buf_size, DMA_TO_DEVICE);
> + kfree(task->va_base);
> +}
> +
> +static void cmdq_task_handle_error(struct cmdq_task *task)
> +{
> + struct cmdq_thread *thread = task->thread;
> + struct cmdq_task *next_task;
> +
> + dev_err(task->cmdq->mbox.dev, "task 0x%p error\n", task);
> + WARN_ON(cmdq_thread_suspend(task->cmdq, thread) < 0);
> + next_task = list_first_entry_or_null(&thread->task_busy_list,
> + struct cmdq_task, list_entry);
> + if (next_task)
> + writel(next_task->pa_base, thread->base + CMDQ_THR_CURR_ADDR);
> + cmdq_thread_resume(thread);
> +}
> +
> +static void cmdq_thread_irq_handler(struct cmdq *cmdq,
> + struct cmdq_thread *thread)
> +{
> + struct cmdq_task *task, *tmp, *curr_task = NULL;
> + u32 curr_pa, irq_flag, task_end_pa;
> + bool err;
> +
> + irq_flag = readl(thread->base + CMDQ_THR_IRQ_STATUS);
> + writel(~irq_flag, thread->base + CMDQ_THR_IRQ_STATUS);
> +
> + /*
> + * When ISR call this function, another CPU core could run
> + * "release task" right before we acquire the spin lock, and thus
> + * reset / disable this GCE thread, so we need to check the enable
> + * bit of this GCE thread.
> + */
> + if (!(readl(thread->base + CMDQ_THR_ENABLE_TASK) & CMDQ_THR_ENABLED))
> + return;
> +
> + if (irq_flag & CMDQ_THR_IRQ_ERROR)
> + err = true;
> + else if (irq_flag & CMDQ_THR_IRQ_DONE)
> + err = false;
> + else
> + return;
> +
> + curr_pa = readl(thread->base + CMDQ_THR_CURR_ADDR);
> +
> + list_for_each_entry_safe(task, tmp, &thread->task_busy_list,
> + list_entry) {
> + task_end_pa = task->pa_base + task->cmd_buf_size;
> + if (curr_pa >= task->pa_base && curr_pa < task_end_pa)
> + curr_task = task;
> +
> + if (!curr_task || curr_pa == task_end_pa - CMDQ_INST_SIZE) {
> + cmdq_task_exec_done(task, false);
> + kfree(task);
> + } else if (err) {
> + cmdq_task_exec_done(task, true);
> + cmdq_task_handle_error(curr_task);
> + kfree(task);
> + }
> +
> + if (curr_task)
> + break;
> + }
> +
> + if (list_empty(&thread->task_busy_list)) {
> + cmdq_thread_disable(cmdq, thread);
> + clk_disable(cmdq->clock);
> + } else {
> + mod_timer(&thread->timeout,
> + jiffies + msecs_to_jiffies(CMDQ_TIMEOUT_MS));
> + }
> +}
> +
> +static irqreturn_t cmdq_irq_handler(int irq, void *dev)
> +{
> + struct cmdq *cmdq = dev;
> + unsigned long irq_status, flags = 0L;
> + int bit;
> +
> + irq_status = readl(cmdq->base + CMDQ_CURR_IRQ_STATUS) & CMDQ_IRQ_MASK;
> + if (!(irq_status ^ CMDQ_IRQ_MASK))
> + return IRQ_NONE;
> +
> + for_each_clear_bit(bit, &irq_status, fls(CMDQ_IRQ_MASK)) {
> + struct cmdq_thread *thread = &cmdq->thread[bit];
> +
> + spin_lock_irqsave(&thread->chan->lock, flags);
> + cmdq_thread_irq_handler(cmdq, thread);
> + spin_unlock_irqrestore(&thread->chan->lock, flags);
> + }
> + return IRQ_HANDLED;
> +}
> +
> +static void cmdq_thread_handle_timeout(unsigned long data)
> +{
> + struct cmdq_thread *thread = (struct cmdq_thread *)data;
> + struct cmdq *cmdq = container_of(thread->chan->mbox, struct cmdq, mbox);
> + struct cmdq_task *task, *tmp;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&thread->chan->lock, flags);
> + WARN_ON(cmdq_thread_suspend(cmdq, thread) < 0);
> +
> + /*
> + * Although IRQ is disabled, GCE continues to execute.
> + * It may have pending IRQ before GCE thread is suspended,
> + * so check this condition again.
> + */
> + cmdq_thread_irq_handler(cmdq, thread);
> +
> + if (list_empty(&thread->task_busy_list)) {
> + cmdq_thread_resume(thread);
> + spin_unlock_irqrestore(&thread->chan->lock, flags);
> + return;
> + }
> +
> + dev_err(cmdq->mbox.dev, "timeout\n");
> + list_for_each_entry_safe(task, tmp, &thread->task_busy_list,
> + list_entry) {
> + cmdq_task_exec_done(task, true);
> + kfree(task);
> + }
> +
> + cmdq_thread_resume(thread);
> + cmdq_thread_disable(cmdq, thread);
> + clk_disable(cmdq->clock);
> + spin_unlock_irqrestore(&thread->chan->lock, flags);
> +}
> +
> +static int cmdq_task_realloc_cmd_buffer(struct cmdq_task *task, size_t size)
> +{
> + void *new_buf;
> +
> + new_buf = krealloc(task->va_base, size, GFP_KERNEL | __GFP_ZERO);
> + if (!new_buf)
> + return -ENOMEM;
> + task->va_base = new_buf;
> + task->buf_size = size;
> + return 0;
> +}
> +
> +struct cmdq_base *cmdq_register_device(struct device *dev)
> +{
> + struct cmdq_base *cmdq_base;
> + struct resource res;
> + int subsys;
> + u32 base;
> +
> + if (of_address_to_resource(dev->of_node, 0, &res))
> + return NULL;
> + base = (u32)res.start;
> +
> + subsys = cmdq_subsys_base_to_id(base >> 16);
> + if (subsys < 0)
> + return NULL;
> +
> + cmdq_base = devm_kmalloc(dev, sizeof(*cmdq_base), GFP_KERNEL);
> + if (!cmdq_base)
> + return NULL;
> + cmdq_base->subsys = subsys;
> + cmdq_base->base = base;
> +
> + return cmdq_base;
> +}
> +EXPORT_SYMBOL(cmdq_register_device);
> +
> +struct cmdq_client *cmdq_mbox_create(struct device *dev, int index)
> +{
> + struct cmdq_client *client;
> +
> + client = kzalloc(sizeof(*client), GFP_KERNEL);
> + client->client.dev = dev;
> + client->client.tx_block = false;
> + client->chan = mbox_request_channel(&client->client, index);
> + return client;
> +}
> +EXPORT_SYMBOL(cmdq_mbox_create);
> +
> +int cmdq_task_create(struct device *dev, struct cmdq_task **task_ptr)
> +{
> + struct cmdq_task *task;
> + int err;
> +
> + task = kzalloc(sizeof(*task), GFP_KERNEL);
> + if (!task)
> + return -ENOMEM;
> + task->cmdq = dev_get_drvdata(dev);
> + err = cmdq_task_realloc_cmd_buffer(task, PAGE_SIZE);
> + if (err < 0) {
> + kfree(task);
> + return err;
> + }
> + *task_ptr = task;
> + return 0;
> +}
> +EXPORT_SYMBOL(cmdq_task_create);
> +
> +static int cmdq_task_append_command(struct cmdq_task *task, enum cmdq_code code,
> + u32 arg_a, u32 arg_b)
> +{
> + u64 *cmd_ptr;
> + int err;
> +
> + if (WARN_ON(task->finalized))
> + return -EBUSY;
> + if (unlikely(task->cmd_buf_size + CMDQ_INST_SIZE > task->buf_size)) {
> + err = cmdq_task_realloc_cmd_buffer(task, task->buf_size * 2);
> + if (err < 0)
> + return err;
> + }
> + cmd_ptr = task->va_base + task->cmd_buf_size;
> + (*cmd_ptr) = (u64)((code << CMDQ_OP_CODE_SHIFT) | arg_a) << 32 | arg_b;
> + task->cmd_buf_size += CMDQ_INST_SIZE;
> + return 0;
> +}
> +
> +int cmdq_task_write(struct cmdq_task *task, u32 value, struct cmdq_base *base,
> + u32 offset)
> +{
> + u32 arg_a = ((base->base + offset) & CMDQ_ARG_A_WRITE_MASK) |
> + (base->subsys << CMDQ_SUBSYS_SHIFT);
> + return cmdq_task_append_command(task, CMDQ_CODE_WRITE, arg_a, value);
> +}
> +EXPORT_SYMBOL(cmdq_task_write);
> +
> +int cmdq_task_write_mask(struct cmdq_task *task, u32 value,
> + struct cmdq_base *base, u32 offset, u32 mask)
> +{
> + u32 offset_mask = offset;
> + int err;
> +
> + if (mask != 0xffffffff) {
> + err = cmdq_task_append_command(task, CMDQ_CODE_MASK, 0, ~mask);
> + if (err < 0)
> + return err;
> + offset_mask |= CMDQ_WRITE_ENABLE_MASK;
> + }
> + return cmdq_task_write(task, value, base, offset_mask);
> +}
> +EXPORT_SYMBOL(cmdq_task_write_mask);
> +
> +static const u32 cmdq_event_value[CMDQ_MAX_EVENT] = {
> + /* Display start of frame(SOF) events */
> + [CMDQ_EVENT_DISP_OVL0_SOF] = 11,
> + [CMDQ_EVENT_DISP_OVL1_SOF] = 12,
> + [CMDQ_EVENT_DISP_RDMA0_SOF] = 13,
> + [CMDQ_EVENT_DISP_RDMA1_SOF] = 14,
> + [CMDQ_EVENT_DISP_RDMA2_SOF] = 15,
> + [CMDQ_EVENT_DISP_WDMA0_SOF] = 16,
> + [CMDQ_EVENT_DISP_WDMA1_SOF] = 17,
> + /* Display end of frame(EOF) events */
> + [CMDQ_EVENT_DISP_OVL0_EOF] = 39,
> + [CMDQ_EVENT_DISP_OVL1_EOF] = 40,
> + [CMDQ_EVENT_DISP_RDMA0_EOF] = 41,
> + [CMDQ_EVENT_DISP_RDMA1_EOF] = 42,
> + [CMDQ_EVENT_DISP_RDMA2_EOF] = 43,
> + [CMDQ_EVENT_DISP_WDMA0_EOF] = 44,
> + [CMDQ_EVENT_DISP_WDMA1_EOF] = 45,
> + /* Mutex end of frame(EOF) events */
> + [CMDQ_EVENT_MUTEX0_STREAM_EOF] = 53,
> + [CMDQ_EVENT_MUTEX1_STREAM_EOF] = 54,
> + [CMDQ_EVENT_MUTEX2_STREAM_EOF] = 55,
> + [CMDQ_EVENT_MUTEX3_STREAM_EOF] = 56,
> + [CMDQ_EVENT_MUTEX4_STREAM_EOF] = 57,
> + /* Display underrun events */
> + [CMDQ_EVENT_DISP_RDMA0_UNDERRUN] = 63,
> + [CMDQ_EVENT_DISP_RDMA1_UNDERRUN] = 64,
> + [CMDQ_EVENT_DISP_RDMA2_UNDERRUN] = 65,
> +};
> +
> +int cmdq_task_wfe(struct cmdq_task *task, enum cmdq_event event)
> +{
> + u32 arg_b;
> +
> + if (event >= CMDQ_MAX_EVENT || event < 0)
> + return -EINVAL;
> +
> + /*
> + * WFE arg_b
> + * bit 0-11: wait value
> + * bit 15: 1 - wait, 0 - no wait
> + * bit 16-27: update value
> + * bit 31: 1 - update, 0 - no update
> + */
> + arg_b = CMDQ_WFE_UPDATE | CMDQ_WFE_WAIT | CMDQ_WFE_WAIT_VALUE;
> + return cmdq_task_append_command(task, CMDQ_CODE_WFE,
> + cmdq_event_value[event], arg_b);
> +}
> +EXPORT_SYMBOL(cmdq_task_wfe);
> +
> +int cmdq_task_clear_event(struct cmdq_task *task, enum cmdq_event event)
> +{
> + if (event >= CMDQ_MAX_EVENT || event < 0)
> + return -EINVAL;
> +
> + return cmdq_task_append_command(task, CMDQ_CODE_WFE,
> + cmdq_event_value[event], CMDQ_WFE_UPDATE);
> +}
> +EXPORT_SYMBOL(cmdq_task_clear_event);
> +
> +static int cmdq_task_finalize(struct cmdq_task *task)
> +{
> + int err;
> +
> + if (task->finalized)
> + return 0;
> +
> + /* insert EOC and generate IRQ for each command iteration */
> + err = cmdq_task_append_command(task, CMDQ_CODE_EOC, 0, CMDQ_EOC_IRQ_EN);
> + if (err < 0)
> + return err;
> +
> + /* JUMP to end */
> + err = cmdq_task_append_command(task, CMDQ_CODE_JUMP, 0, CMDQ_JUMP_PASS);
> + if (err < 0)
> + return err;
> +
> + task->finalized = true;
> + return 0;
> +}
> +
> +int cmdq_task_flush_async(struct cmdq_client *client, struct cmdq_task *task,
> + cmdq_async_flush_cb cb, void *data)
> +{
> + struct cmdq *cmdq = task->cmdq;
> + int err;
> +
> + mutex_lock(&cmdq->task_mutex);
> + if (cmdq->suspended) {
> + dev_err(cmdq->mbox.dev, "%s is called after suspended\n",
> + __func__);
> + mutex_unlock(&cmdq->task_mutex);
> + return -EPERM;
> + }
> +
> + err = cmdq_task_finalize(task);
> + if (err < 0) {
> + mutex_unlock(&cmdq->task_mutex);
> + return err;
> + }
> +
> + INIT_LIST_HEAD(&task->list_entry);
> + task->cb.cb = cb;
> + task->cb.data = data;
> + task->pa_base = dma_map_single(cmdq->mbox.dev, task->va_base,
> + task->cmd_buf_size, DMA_TO_DEVICE);
> +
> + mbox_send_message(client->chan, task);
> + /* We can send next task immediately, so just call txdone. */
> + mbox_client_txdone(client->chan, 0);
> + mutex_unlock(&cmdq->task_mutex);
> + return 0;
> +}
> +EXPORT_SYMBOL(cmdq_task_flush_async);
> +
> +struct cmdq_flush_completion {
> + struct completion cmplt;
> + bool err;
> +};
> +
> +static void cmdq_task_flush_cb(struct cmdq_cb_data data)
> +{
> + struct cmdq_flush_completion *cmplt = data.data;
> +
> + cmplt->err = data.err;
> + complete(&cmplt->cmplt);
> +}
> +
> +int cmdq_task_flush(struct cmdq_client *client, struct cmdq_task *task)
> +{
> + struct cmdq_flush_completion cmplt;
> + int err;
> +
> + init_completion(&cmplt.cmplt);
> + err = cmdq_task_flush_async(client, task, cmdq_task_flush_cb, &cmplt);
> + if (err < 0)
> + return err;
> + wait_for_completion(&cmplt.cmplt);
> + return cmplt.err ? -EFAULT : 0;
> +}
> +EXPORT_SYMBOL(cmdq_task_flush);
> +
> +void cmdq_mbox_free(struct cmdq_client *client)
> +{
> + mbox_free_channel(client->chan);
> + kfree(client);
> +}
> +EXPORT_SYMBOL(cmdq_mbox_free);
> +
All these exported functions implement the protocol, so should not be
a part of this controller driver. That should go into
drivers/soc/mediatek/
The controller driver (mtk-cmdq.c) should implement mainly the
mbox_chan_ops and mbox.of_xlate.
> +static int cmdq_suspend(struct device *dev)
> +{
> + struct cmdq *cmdq = dev_get_drvdata(dev);
> + struct cmdq_thread *thread;
> + int i;
> + bool task_running = false;
> +
> + mutex_lock(&cmdq->task_mutex);
> + cmdq->suspended = true;
> + mutex_unlock(&cmdq->task_mutex);
> +
> + for (i = 0; i < ARRAY_SIZE(cmdq->thread); i++) {
> + thread = &cmdq->thread[i];
> + if (!list_empty(&thread->task_busy_list)) {
> + mod_timer(&thread->timeout, jiffies + 1);
> + task_running = true;
> + }
> + }
> +
> + if (task_running) {
> + dev_warn(dev, "exist running task(s) in suspend\n");
> + msleep(20);
> + }
> +
> + clk_unprepare(cmdq->clock);
> + return 0;
> +}
> +
> +static int cmdq_resume(struct device *dev)
> +{
> + struct cmdq *cmdq = dev_get_drvdata(dev);
> +
> + WARN_ON(clk_prepare(cmdq->clock) < 0);
> + cmdq->suspended = false;
> + return 0;
> +}
> +
> +static int cmdq_remove(struct platform_device *pdev)
> +{
> + struct cmdq *cmdq = platform_get_drvdata(pdev);
> +
> + mbox_controller_unregister(&cmdq->mbox);
> + clk_unprepare(cmdq->clock);
> + return 0;
> +}
> +
> +static int cmdq_mbox_send_data(struct mbox_chan *chan, void *data)
> +{
> + cmdq_task_exec(data, chan->con_priv);
> + return 0;
> +}
> +
> +static int cmdq_mbox_startup(struct mbox_chan *chan)
> +{
> + return 0;
> +}
> +
> +static void cmdq_mbox_shutdown(struct mbox_chan *chan)
> +{
> +}
> +
> +static bool cmdq_mbox_last_tx_done(struct mbox_chan *chan)
> +{
> + return true;
> +}
> +
> +static const struct mbox_chan_ops cmdq_mbox_chan_ops = {
> + .send_data = cmdq_mbox_send_data,
> + .startup = cmdq_mbox_startup,
> + .shutdown = cmdq_mbox_shutdown,
> + .last_tx_done = cmdq_mbox_last_tx_done,
> +};
> +
> +static struct mbox_chan *cmdq_xlate(struct mbox_controller *mbox,
> + const struct of_phandle_args *sp)
> +{
> + int ind = sp->args[0];
> + struct cmdq_thread *thread;
> +
> + if (ind >= mbox->num_chans)
> + return ERR_PTR(-EINVAL);
> +
> + thread = mbox->chans[ind].con_priv;
> + thread->atomic_exec = (sp->args[1] != 0);
> + thread->chan = &mbox->chans[ind];
> +
> + return &mbox->chans[ind];
> +}
> +
> +static int cmdq_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct device_node *node = dev->of_node;
> + struct resource *res;
> + struct cmdq *cmdq;
> + int err, i;
> +
> + cmdq = devm_kzalloc(dev, sizeof(*cmdq), GFP_KERNEL);
> + if (!cmdq)
> + return -ENOMEM;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + cmdq->base = devm_ioremap_resource(dev, res);
> + if (IS_ERR(cmdq->base)) {
> + dev_err(dev, "failed to ioremap gce\n");
> + return PTR_ERR(cmdq->base);
> + }
> +
> + cmdq->irq = irq_of_parse_and_map(node, 0);
>
why not, cmdq->irq = platform_get_irq(pdev, 0);
> + if (!cmdq->irq) {
> + dev_err(dev, "failed to get irq\n");
> + return -EINVAL;
> + }
> + err = devm_request_irq(dev, cmdq->irq, cmdq_irq_handler, IRQF_SHARED,
> + "mtk_cmdq", cmdq);
> + if (err < 0) {
> + dev_err(dev, "failed to register ISR (%d)\n", err);
> + return err;
> + }
> +
> + dev_dbg(dev, "cmdq device: addr:0x%p, va:0x%p, irq:%d\n",
> + dev, cmdq->base, cmdq->irq);
> +
> + cmdq->clock = devm_clk_get(dev, "gce");
> + if (IS_ERR(cmdq->clock)) {
> + dev_err(dev, "failed to get gce clk\n");
> + return PTR_ERR(cmdq->clock);
> + }
> +
> + mutex_init(&cmdq->task_mutex);
> +
> + cmdq->mbox.dev = dev;
> + cmdq->mbox.chans = devm_kcalloc(dev, CMDQ_THR_MAX_COUNT,
> + sizeof(*cmdq->mbox.chans), GFP_KERNEL);
> + if (!cmdq->mbox.chans)
> + return -ENOMEM;
> +
> + cmdq->mbox.num_chans = CMDQ_THR_MAX_COUNT;
> + cmdq->mbox.ops = &cmdq_mbox_chan_ops;
> + cmdq->mbox.of_xlate = cmdq_xlate;
> +
> + /* make use of TXDONE_BY_ACK */
> + cmdq->mbox.txdone_irq = false;
> + cmdq->mbox.txdone_poll = false;
> +
> + for (i = 0; i < ARRAY_SIZE(cmdq->thread); i++) {
> + cmdq->thread[i].base = cmdq->base + CMDQ_THR_BASE +
> + CMDQ_THR_SIZE * i;
> + INIT_LIST_HEAD(&cmdq->thread[i].task_busy_list);
> + init_timer(&cmdq->thread[i].timeout);
> + cmdq->thread[i].timeout.function = cmdq_thread_handle_timeout;
> + cmdq->thread[i].timeout.data = (unsigned long)&cmdq->thread[i];
> + cmdq->mbox.chans[i].con_priv = &cmdq->thread[i];
> + }
> +
> + err = mbox_controller_register(&cmdq->mbox);
> + if (err < 0) {
> + dev_err(dev, "failed to register mailbox: %d\n", err);
> + return err;
> + }
> +
> + platform_set_drvdata(pdev, cmdq);
> + WARN_ON(clk_prepare(cmdq->clock) < 0);
> + return 0;
> +}
> +
> +static const struct dev_pm_ops cmdq_pm_ops = {
> + .suspend = cmdq_suspend,
> + .resume = cmdq_resume,
> +};
> +
> +static const struct of_device_id cmdq_of_ids[] = {
> + {.compatible = "mediatek,mt8173-gce",},
> + {}
> +};
> +
> +static struct platform_driver cmdq_drv = {
> + .probe = cmdq_probe,
> + .remove = cmdq_remove,
> + .driver = {
> + .name = "mtk_cmdq",
> + .owner = THIS_MODULE,
>
please remove the unnecessary .owner field.
> + .pm = &cmdq_pm_ops,
> + .of_match_table = cmdq_of_ids,
> + }
> +};
> +
> +builtin_platform_driver(cmdq_drv);
> diff --git a/include/linux/mailbox/mtk-cmdq.h b/include/linux/mailbox/mtk-cmdq.h
> new file mode 100644
> index 0000000..c3c924d
> --- /dev/null
> +++ b/include/linux/mailbox/mtk-cmdq.h
>
The api implemented is Mediateck proprietary, so I think it should be
include/linux/soc/mediatek/cmdq.h
> @@ -0,0 +1,180 @@
> +/*
> + * Copyright (c) 2015 MediaTek Inc.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#ifndef __MTK_CMDQ_H__
> +#define __MTK_CMDQ_H__
> +
> +#include <linux/mailbox_client.h>
> +#include <linux/mailbox_controller.h>
>
Clients should not need to include mailbox_controller.h
> +#include <linux/platform_device.h>
> +#include <linux/types.h>
> +
> +/* display events in command queue(CMDQ) */
> +enum cmdq_event {
> + /* Display start of frame(SOF) events */
> + CMDQ_EVENT_DISP_OVL0_SOF,
>
you may want to explicitly initialise the first element.
> + CMDQ_EVENT_DISP_OVL1_SOF,
> + CMDQ_EVENT_DISP_RDMA0_SOF,
> + CMDQ_EVENT_DISP_RDMA1_SOF,
> + CMDQ_EVENT_DISP_RDMA2_SOF,
> + CMDQ_EVENT_DISP_WDMA0_SOF,
> + CMDQ_EVENT_DISP_WDMA1_SOF,
> + /* Display end of frame(EOF) events */
> + CMDQ_EVENT_DISP_OVL0_EOF,
> + CMDQ_EVENT_DISP_OVL1_EOF,
> + CMDQ_EVENT_DISP_RDMA0_EOF,
> + CMDQ_EVENT_DISP_RDMA1_EOF,
> + CMDQ_EVENT_DISP_RDMA2_EOF,
> + CMDQ_EVENT_DISP_WDMA0_EOF,
> + CMDQ_EVENT_DISP_WDMA1_EOF,
> + /* Mutex end of frame(EOF) events */
> + CMDQ_EVENT_MUTEX0_STREAM_EOF,
> + CMDQ_EVENT_MUTEX1_STREAM_EOF,
> + CMDQ_EVENT_MUTEX2_STREAM_EOF,
> + CMDQ_EVENT_MUTEX3_STREAM_EOF,
> + CMDQ_EVENT_MUTEX4_STREAM_EOF,
> + /* Display underrun events */
> + CMDQ_EVENT_DISP_RDMA0_UNDERRUN,
> + CMDQ_EVENT_DISP_RDMA1_UNDERRUN,
> + CMDQ_EVENT_DISP_RDMA2_UNDERRUN,
> + /* Keep this at the end */
> + CMDQ_MAX_EVENT,
> +};
> +