v4.19.13 snapshot.
diff --git a/drivers/mailbox/mtk-cmdq-mailbox.c b/drivers/mailbox/mtk-cmdq-mailbox.c
new file mode 100644
index 0000000..aec46d5
--- /dev/null
+++ b/drivers/mailbox/mtk-cmdq-mailbox.c
@@ -0,0 +1,571 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (c) 2018 MediaTek Inc.
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/dma-mapping.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/mailbox_controller.h>
+#include <linux/mailbox/mtk-cmdq-mailbox.h>
+#include <linux/of_device.h>
+
+#define CMDQ_OP_CODE_MASK (0xff << CMDQ_OP_CODE_SHIFT)
+#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_PRIORITY 0x40
+
+#define CMDQ_THR_ACTIVE_SLOT_CYCLES 0x3200
+#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_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_JUMP_BY_OFFSET 0x10000000
+#define CMDQ_JUMP_BY_PA 0x10000001
+
+struct cmdq_thread {
+ struct mbox_chan *chan;
+ void __iomem *base;
+ struct list_head task_busy_list;
+ u32 priority;
+ bool atomic_exec;
+};
+
+struct cmdq_task {
+ struct cmdq *cmdq;
+ struct list_head list_entry;
+ dma_addr_t pa_base;
+ struct cmdq_thread *thread;
+ struct cmdq_pkt *pkt; /* the packet sent from mailbox client */
+};
+
+struct cmdq {
+ struct mbox_controller mbox;
+ void __iomem *base;
+ u32 irq;
+ u32 thread_nr;
+ struct cmdq_thread *thread;
+ struct clk *clock;
+ bool suspended;
+};
+
+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 void cmdq_init(struct cmdq *cmdq)
+{
+ WARN_ON(clk_enable(cmdq->clock) < 0);
+ writel(CMDQ_THR_ACTIVE_SLOT_CYCLES, cmdq->base + CMDQ_THR_SLOT_CYCLES);
+ clk_disable(cmdq->clock);
+}
+
+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;
+ }
+
+ 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->pkt->va_base;
+
+ /* let previous task jump to this task */
+ dma_sync_single_for_cpu(dev, prev_task->pa_base,
+ prev_task->pkt->cmd_buf_size, DMA_TO_DEVICE);
+ prev_task_base[CMDQ_NUM_CMD(prev_task->pkt) - 1] =
+ (u64)CMDQ_JUMP_BY_PA << 32 | task->pa_base;
+ dma_sync_single_for_device(dev, prev_task->pa_base,
+ prev_task->pkt->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->pkt->va_base;
+ int i;
+
+ dma_sync_single_for_cpu(dev, task->pa_base, task->pkt->cmd_buf_size,
+ DMA_TO_DEVICE);
+ for (i = 0; i < CMDQ_NUM_CMD(task->pkt); 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->pkt->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_done(struct cmdq_task *task, enum cmdq_cb_status sta)
+{
+ struct cmdq_task_cb *cb = &task->pkt->async_cb;
+ struct cmdq_cb_data data;
+
+ WARN_ON(cb->cb == (cmdq_async_flush_cb)NULL);
+ data.sta = sta;
+ data.data = cb->data;
+ cb->cb(data);
+
+ list_del(&task->list_entry);
+}
+
+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->pkt->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, CMDQ_CB_NORMAL);
+ kfree(task);
+ } else if (err) {
+ cmdq_task_exec_done(task, CMDQ_CB_ERROR);
+ 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);
+ }
+}
+
+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 int cmdq_suspend(struct device *dev)
+{
+ struct cmdq *cmdq = dev_get_drvdata(dev);
+ struct cmdq_thread *thread;
+ int i;
+ bool task_running = false;
+
+ cmdq->suspended = true;
+
+ for (i = 0; i < cmdq->thread_nr; i++) {
+ thread = &cmdq->thread[i];
+ if (!list_empty(&thread->task_busy_list)) {
+ task_running = true;
+ break;
+ }
+ }
+
+ if (task_running)
+ dev_warn(dev, "exist running task(s) in suspend\n");
+
+ 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);
+
+ if (cmdq->mbox.chans)
+ devm_kfree(&pdev->dev, cmdq->mbox.chans);
+
+ if (cmdq->thread)
+ devm_kfree(&pdev->dev, cmdq->thread);
+
+ devm_kfree(&pdev->dev, cmdq);
+
+ return 0;
+}
+
+static int cmdq_mbox_send_data(struct mbox_chan *chan, void *data)
+{
+ struct cmdq_pkt *pkt = (struct cmdq_pkt *)data;
+ struct cmdq_thread *thread = (struct cmdq_thread *)chan->con_priv;
+ struct cmdq *cmdq = dev_get_drvdata(chan->mbox->dev);
+ struct cmdq_task *task;
+ unsigned long curr_pa, end_pa;
+
+ /* Client should not flush new tasks if suspended. */
+ WARN_ON(cmdq->suspended);
+
+ task = kzalloc(sizeof(*task), GFP_ATOMIC);
+ task->cmdq = cmdq;
+ INIT_LIST_HEAD(&task->list_entry);
+ task->pa_base = pkt->pa_base;
+ task->thread = thread;
+ task->pkt = pkt;
+
+ 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 + pkt->cmd_buf_size,
+ thread->base + CMDQ_THR_END_ADDR);
+ writel(thread->priority, thread->base + CMDQ_THR_PRIORITY);
+ writel(CMDQ_THR_IRQ_EN, thread->base + CMDQ_THR_IRQ_ENABLE);
+ writel(CMDQ_THR_ENABLED, thread->base + CMDQ_THR_ENABLE_TASK);
+ } 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 + pkt->cmd_buf_size,
+ thread->base + CMDQ_THR_END_ADDR);
+ cmdq_thread_resume(thread);
+ }
+ list_move_tail(&task->list_entry, &thread->task_busy_list);
+
+ return 0;
+}
+
+static int cmdq_mbox_startup(struct mbox_chan *chan)
+{
+ return 0;
+}
+
+static void cmdq_mbox_shutdown(struct mbox_chan *chan)
+{
+}
+
+static const struct mbox_chan_ops cmdq_mbox_chan_ops = {
+ .send_data = cmdq_mbox_send_data,
+ .startup = cmdq_mbox_startup,
+ .shutdown = cmdq_mbox_shutdown,
+};
+
+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 = (struct cmdq_thread *)mbox->chans[ind].con_priv;
+ thread->priority = sp->args[1];
+ thread->atomic_exec = (sp->args[2] != 0);
+ thread->chan = &mbox->chans[ind];
+
+ return &mbox->chans[ind];
+}
+
+static int cmdq_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ 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 = 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);
+ }
+
+ cmdq->thread_nr = (u32)(unsigned long)of_device_get_match_data(dev);
+ cmdq->mbox.dev = dev;
+ cmdq->mbox.chans = devm_kcalloc(dev, cmdq->thread_nr,
+ sizeof(*cmdq->mbox.chans), GFP_KERNEL);
+ if (!cmdq->mbox.chans)
+ return -ENOMEM;
+
+ cmdq->mbox.num_chans = cmdq->thread_nr;
+ 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;
+
+ cmdq->thread = devm_kcalloc(dev, cmdq->thread_nr,
+ sizeof(*cmdq->thread), GFP_KERNEL);
+ if (!cmdq->thread)
+ return -ENOMEM;
+
+ for (i = 0; i < cmdq->thread_nr; i++) {
+ cmdq->thread[i].base = cmdq->base + CMDQ_THR_BASE +
+ CMDQ_THR_SIZE * i;
+ INIT_LIST_HEAD(&cmdq->thread[i].task_busy_list);
+ cmdq->mbox.chans[i].con_priv = (void *)&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);
+
+ cmdq_init(cmdq);
+
+ 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", .data = (void *)16},
+ {}
+};
+
+static struct platform_driver cmdq_drv = {
+ .probe = cmdq_probe,
+ .remove = cmdq_remove,
+ .driver = {
+ .name = "mtk_cmdq",
+ .pm = &cmdq_pm_ops,
+ .of_match_table = cmdq_of_ids,
+ }
+};
+
+static int __init cmdq_drv_init(void)
+{
+ return platform_driver_register(&cmdq_drv);
+}
+
+static void __exit cmdq_drv_exit(void)
+{
+ platform_driver_unregister(&cmdq_drv);
+}
+
+subsys_initcall(cmdq_drv_init);
+module_exit(cmdq_drv_exit);
+
+MODULE_LICENSE("GPL v2");