drm/amdgpu: busywait KIQ register accessing (v4)
Register accessing is performed when IRQ is disabled. Never sleep in
this function.
Known issue: dead sleep in many use cases of index/data registers.
v2:
- wrap polling fence functions.
- don't trigger IRQ for polling in case of wrongly fence signal.
v3:
- handle wrap round gracefully.
- add comments for polling function
v4:
- don't return negative timeout confused with error code
Signed-off-by: pding <Pixel.Ding@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
index 0d9ce14..b18c2b96 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ring.h
@@ -90,8 +90,12 @@ int amdgpu_fence_driver_start_ring(struct amdgpu_ring *ring,
void amdgpu_fence_driver_suspend(struct amdgpu_device *adev);
void amdgpu_fence_driver_resume(struct amdgpu_device *adev);
int amdgpu_fence_emit(struct amdgpu_ring *ring, struct dma_fence **fence);
+int amdgpu_fence_emit_polling(struct amdgpu_ring *ring, uint32_t *s);
void amdgpu_fence_process(struct amdgpu_ring *ring);
int amdgpu_fence_wait_empty(struct amdgpu_ring *ring);
+signed long amdgpu_fence_wait_polling(struct amdgpu_ring *ring,
+ uint32_t wait_seq,
+ signed long timeout);
unsigned amdgpu_fence_count_emitted(struct amdgpu_ring *ring);
/*