drm/amdgpu: Reset error code for 'no handler' case

If reset handler is not implemented, reset error before proceeding.

Fixes issue with the following trace -
[  106.508592] amdgpu 0000:b1:00.0: amdgpu: ASIC reset failed with error, -38 for drm dev, 0000:b1:00.0
[  106.508972] amdgpu 0000:b1:00.0: amdgpu: GPU reset succeeded, trying to resume
[  106.509116] [drm] PCIE GART of 512M enabled.
[  106.509120] [drm] PTB located at 0x0000008000000000
[  106.509136] [drm] VRAM is lost due to GPU reset!
[  106.509332] [drm] PSP is resuming...
Signed-off-by: Lijo Lazar <lijo.lazar@amd.com>
Reviewed-and-tested-by: Guchun Chen <guchun.chen@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_device.c

@@ -4281,7 +4281,10 @@ int amdgpu_device_pre_asic_reset(struct amdgpu_device *adev,
 		drm_sched_increase_karma(&job->base);
 
 	r = amdgpu_reset_prepare_hwcontext(adev, reset_context);
-	if (r != -ENOSYS)
+	/* If reset handler not implemented, continue; otherwise return */
+	if (r == -ENOSYS)
+		r = 0;
+	else
 		return r;
 
 	/* Don't suspend on bare metal if we are not going to HW reset the ASIC */
@@ -4323,8 +4326,10 @@ int amdgpu_do_asic_reset(struct list_head *device_list_handle,
 	tmp_adev = list_first_entry(device_list_handle, struct amdgpu_device,
 				    reset_list);
 	r = amdgpu_reset_perform_reset(tmp_adev, reset_context);
-
-	if (r != -ENOSYS)
+	/* If reset handler not implemented, continue; otherwise return */
+	if (r == -ENOSYS)
+		r = 0;
+	else
 		return r;
 
 	/* Reset handler not implemented, use the default method */