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_gfx.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c
index 83435cc..ef04336 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gfx.c
@@ -201,7 +201,7 @@ int amdgpu_gfx_kiq_init_ring(struct amdgpu_device *adev,
struct amdgpu_kiq *kiq = &adev->gfx.kiq;
int r = 0;
- mutex_init(&kiq->ring_mutex);
+ spin_lock_init(&kiq->ring_lock);
r = amdgpu_wb_get(adev, &adev->virt.reg_val_offs);
if (r)