drm/amdgpu: add a amdgpu_device_supports_baco helper

BACO - Bus Active, Chip Off

To check if a device supports BACO or not.  This will be
used in determining when to enable runtime pm.
Reviewed-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -1141,6 +1141,7 @@ void amdgpu_device_program_register_sequence(struct amdgpu_device *adev,
 					     const u32 array_size);
 
 bool amdgpu_device_is_px(struct drm_device *dev);
+bool amdgpu_device_supports_baco(struct drm_device *dev);
 bool amdgpu_device_is_peer_accessible(struct amdgpu_device *adev,
 				      struct amdgpu_device *peer_adev);
 

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

@@ -153,6 +153,21 @@ bool amdgpu_device_is_px(struct drm_device *dev)
 	return false;
 }
 
+/**
+ * amdgpu_device_supports_baco - Does the device support BACO
+ *
+ * @dev: drm_device pointer
+ *
+ * Returns true if the device supporte BACO,
+ * otherwise return false.
+ */
+bool amdgpu_device_supports_baco(struct drm_device *dev)
+{
+	struct amdgpu_device *adev = dev->dev_private;
+
+	return amdgpu_asic_supports_baco(adev);
+}
+
 /**
  * VRAM access helper functions.
  *