[PATCH V1] accel/amdxdna: Fix command hang on suspended hardware context

[Lizhi Hou]

When a hardware context is suspended, the job scheduler is stopped. If a
command is submitted while the context is suspended, the job is queued in
the scheduler but aie2_sched_job_run() is never invoked to restart the
hardware context. As a result, the command hangs.

Fix this by modifying the hardware context suspend routine to keep the job
scheduler running so that queued jobs can trigger context restart properly.

Fixes: aac243092b70 ("accel/amdxdna: Add command execution")
Signed-off-by: Lizhi Hou <lizhi....@amd.com>
---
 drivers/accel/amdxdna/aie2_ctx.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/accel/amdxdna/aie2_ctx.c b/drivers/accel/amdxdna/aie2_ctx.c
index 89c0ab896f92..622ddbf7fb6f 100644
--- a/drivers/accel/amdxdna/aie2_ctx.c
+++ b/drivers/accel/amdxdna/aie2_ctx.c
@@ -53,6 +53,7 @@ static void aie2_hwctx_stop(struct amdxdna_dev *xdna, struct 
amdxdna_hwctx *hwct
 {
        drm_sched_stop(&hwctx->priv->sched, bad_job);
        aie2_destroy_context(xdna->dev_handle, hwctx);
+       drm_sched_start(&hwctx->priv->sched, 0);
 }
 
 static int aie2_hwctx_restart(struct amdxdna_dev *xdna, struct amdxdna_hwctx 
*hwctx)
@@ -80,7 +81,6 @@ static int aie2_hwctx_restart(struct amdxdna_dev *xdna, 
struct amdxdna_hwctx *hw
        }
 
 out:
-       drm_sched_start(&hwctx->priv->sched, 0);
        XDNA_DBG(xdna, "%s restarted, ret %d", hwctx->name, ret);
        return ret;
 }
@@ -297,19 +297,23 @@ aie2_sched_job_run(struct drm_sched_job *sched_job)
        struct dma_fence *fence;
        int ret;
 
-       if (!hwctx->priv->mbox_chann)
+       ret = amdxdna_pm_resume_get(hwctx->client->xdna);
+       if (ret)
+               return NULL;
+
+       if (!hwctx->priv->mbox_chann) {
+               amdxdna_pm_suspend_put(hwctx->client->xdna);
                return NULL;
+       }
 
-       if (!mmget_not_zero(job->mm))
+       if (!mmget_not_zero(job->mm)) {
+               amdxdna_pm_suspend_put(hwctx->client->xdna);
                return ERR_PTR(-ESRCH);
+       }
 
        kref_get(&job->refcnt);
        fence = dma_fence_get(job->fence);
 
-       ret = amdxdna_pm_resume_get(hwctx->client->xdna);
-       if (ret)
-               goto out;
-
        if (job->drv_cmd) {
                switch (job->drv_cmd->opcode) {
                case SYNC_DEBUG_BO:
-- 
2.34.1