drm/amdgpu/soc15: add PCI reset support

Use generic PCI reset for GPU reset if the user specifies
PCI reset as the reset mechanism.  This should in general
only be used for validation.
Acked-by: Evan Quan <evan.quan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/soc15.c

@@ -479,7 +479,8 @@ soc15_asic_reset_method(struct amdgpu_device *adev)
 
 	if (amdgpu_reset_method == AMD_RESET_METHOD_MODE1 ||
 	    amdgpu_reset_method == AMD_RESET_METHOD_MODE2 ||
-		amdgpu_reset_method == AMD_RESET_METHOD_BACO)
+	    amdgpu_reset_method == AMD_RESET_METHOD_BACO ||
+	    amdgpu_reset_method == AMD_RESET_METHOD_PCI)
 		return amdgpu_reset_method;
 
 	if (amdgpu_reset_method != -1)
@@ -524,6 +525,9 @@ static int soc15_asic_reset(struct amdgpu_device *adev)
 		return 0;
 
 	switch (soc15_asic_reset_method(adev)) {
+	case AMD_RESET_METHOD_PCI:
+		dev_info(adev->dev, "PCI reset\n");
+		return amdgpu_device_pci_reset(adev);
 	case AMD_RESET_METHOD_BACO:
 		dev_info(adev->dev, "BACO reset\n");
 		return soc15_asic_baco_reset(adev);