[PATCH v3 3/9] drm/panfrost: Handle job HW submit errors

[Adrián Larumbe]

Avoid waiting for the DRM scheduler job timedout handler, and instead, let
the DRM scheduler core signal the error fence immediately when HW job
submission fails.

That means we must also decrement the runtime-PM refcnt for the device,
because the job will never be enqueued or inflight.

Reviewed-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxx>
Signed-off-by: Adrián Larumbe <adrian.larumbe@xxxxxxxxxxxxx>
---
 drivers/gpu/drm/panfrost/panfrost_job.c | 20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/panfrost/panfrost_job.c b/drivers/gpu/drm/panfrost/panfrost_job.c
index f640d211cc3a..83bc74f6044e 100644
--- a/drivers/gpu/drm/panfrost/panfrost_job.c
+++ b/drivers/gpu/drm/panfrost/panfrost_job.c
@@ -195,7 +195,7 @@ panfrost_enqueue_job(struct panfrost_device *pfdev, int slot,
 	return 1;
 }
 
-static void panfrost_job_hw_submit(struct panfrost_job *job, int js)
+static int panfrost_job_hw_submit(struct panfrost_job *job, int js)
 {
 	struct panfrost_device *pfdev = job->pfdev;
 	unsigned int subslot;
@@ -207,10 +207,11 @@ static void panfrost_job_hw_submit(struct panfrost_job *job, int js)
 
 	ret = pm_runtime_get_sync(pfdev->base.dev);
 	if (ret < 0)
-		return;
+		goto err_hwsubmit;
 
 	if (WARN_ON(job_read(pfdev, JS_COMMAND_NEXT(js)))) {
-		return;
+		ret = -EINVAL;
+		goto err_hwsubmit;
 	}
 
 	cfg = panfrost_mmu_as_get(pfdev, job->mmu);
@@ -261,6 +262,12 @@ static void panfrost_job_hw_submit(struct panfrost_job *job, int js)
 			job, js, subslot, jc_head, cfg & 0xf);
 	}
 	spin_unlock(&pfdev->js->job_lock);
+
+	return 0;
+
+err_hwsubmit:
+	pm_runtime_put_autosuspend(pfdev->base.dev);
+	return ret;
 }
 
 static int panfrost_acquire_object_fences(struct drm_gem_object **bos,
@@ -382,6 +389,7 @@ static struct dma_fence *panfrost_job_run(struct drm_sched_job *sched_job)
 	struct panfrost_device *pfdev = job->pfdev;
 	int slot = panfrost_job_get_slot(job);
 	struct dma_fence *fence = NULL;
+	int ret;
 
 	if (unlikely(job->base.s_fence->finished.error))
 		return NULL;
@@ -400,7 +408,11 @@ static struct dma_fence *panfrost_job_run(struct drm_sched_job *sched_job)
 		dma_fence_put(job->done_fence);
 	job->done_fence = dma_fence_get(fence);
 
-	panfrost_job_hw_submit(job, slot);
+	ret = panfrost_job_hw_submit(job, slot);
+	if (ret) {
+		dma_fence_put(fence);
+		return ERR_PTR(ret);
+	}
 
 	return fence;
 }
-- 
2.47.0