drm/amdgpu: add check_soft_reset ip func

It is used to identify if the ip block is hang.
Signed-off-by: Chunming Zhou <David1.Zhou@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu.h

@@ -1956,6 +1956,7 @@ struct amdgpu_ip_block_status {
 	bool valid;
 	bool sw;
 	bool hw;
+	bool hang;
 };
 
 struct amdgpu_device {

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

@@ -1937,6 +1937,24 @@ int amdgpu_resume_kms(struct drm_device *dev, bool resume, bool fbcon)
 	return 0;
 }
 
+static bool amdgpu_check_soft_reset(struct amdgpu_device *adev)
+{
+	int i;
+	bool asic_hang = false;
+
+	for (i = 0; i < adev->num_ip_blocks; i++) {
+		if (!adev->ip_block_status[i].valid)
+			continue;
+		if (adev->ip_blocks[i].funcs->check_soft_reset)
+			adev->ip_blocks[i].funcs->check_soft_reset(adev);
+		if (adev->ip_block_status[i].hang) {
+			DRM_INFO("IP block:%d is hang!\n", i);
+			asic_hang = true;
+		}
+	}
+	return asic_hang;
+}
+
 /**
  * amdgpu_gpu_reset - reset the asic
  *
@@ -1950,6 +1968,11 @@ int amdgpu_gpu_reset(struct amdgpu_device *adev)
 	int i, r;
 	int resched;
 
+	if (!amdgpu_check_soft_reset(adev)) {
+		DRM_INFO("No hardware hang detected. Did some blocks stall?\n");
+		return 0;
+	}
+
 	atomic_inc(&adev->gpu_reset_counter);
 
 	/* block TTM */

drivers/gpu/drm/amd/include/amd_shared.h

@@ -159,6 +159,8 @@ struct amd_ip_funcs {
 	bool (*is_idle)(void *handle);
 	/* poll for idle */
 	int (*wait_for_idle)(void *handle);
+	/* check soft reset the IP block */
+	int (*check_soft_reset)(void *handle);
 	/* soft reset the IP block */
 	int (*soft_reset)(void *handle);
 	/* enable/disable cg for the IP block */