[RESEND PATCH v1 2/2] Revert "mailbox: mediatek: remove implementation related to atomic_exec"

From: Yongqiang Niu
Date: Wed Mar 10 2021 - 05:57:55 EST


This reverts commit c9ea564f3d9dd20d88bd34f40a6ff6d31a0d7e8c.

Signed-off-by: Yongqiang Niu <yongqiang.niu@xxxxxxxxxxxx>
---
drivers/mailbox/mtk-cmdq-mailbox.c | 80 +++++++++++++++++++++++++++++++++-----
1 file changed, 71 insertions(+), 9 deletions(-)

diff --git a/drivers/mailbox/mtk-cmdq-mailbox.c b/drivers/mailbox/mtk-cmdq-mailbox.c
index 5665b6e..e0d9a86 100644
--- a/drivers/mailbox/mtk-cmdq-mailbox.c
+++ b/drivers/mailbox/mtk-cmdq-mailbox.c
@@ -56,6 +56,7 @@ struct cmdq_thread {
void __iomem *base;
struct list_head task_busy_list;
u32 priority;
+ bool atomic_exec;
};

struct cmdq_task {
@@ -168,18 +169,56 @@ static void cmdq_task_insert_into_thread(struct cmdq_task *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;
+ (u64)CMDQ_JUMP_BY_PA << 32 |
+ (task->pa_base >> task->cmdq->shift_pa);
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 >> task->cmdq->shift_pa);
+ 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;
@@ -371,15 +410,37 @@ static int cmdq_mbox_send_data(struct mbox_chan *chan, void *data)
cmdq->shift_pa;
end_pa = readl(thread->base + CMDQ_THR_END_ADDR) <<
cmdq->shift_pa;
- /* check boundary */
- if (curr_pa == end_pa - CMDQ_INST_SIZE ||
- curr_pa == end_pa) {
- /* set to this task directly */
- writel(task->pa_base >> cmdq->shift_pa,
- thread->base + CMDQ_THR_CURR_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 >> cmdq->shift_pa);
+ WARN_ON(cmdq_thread_suspend(cmdq, thread) < 0);
+ /* set to this task directly */
+ writel(task->pa_base >> cmdq->shift_pa,
+ 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 {
- cmdq_task_insert_into_thread(task);
- smp_mb(); /* modify jump before enable thread */
+ /* check boundary */
+ if (curr_pa == end_pa - CMDQ_INST_SIZE ||
+ curr_pa == end_pa) {
+ /* set to this task directly */
+ writel(task->pa_base >> cmdq->shift_pa,
+ 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) >> cmdq->shift_pa,
thread->base + CMDQ_THR_END_ADDR);
@@ -500,6 +561,7 @@ static struct mbox_chan *cmdq_xlate(struct mbox_controller *mbox,

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];
--
1.8.1.1.dirty