drm/radeon: wire up a pci shutdown callback

Normally on shutdown or reboot we don't care about necessarily
making sure the hw is in a good state because the system is about
to be powered down or reset.  However, after a shutdown or reboot
in a VM, it's best to tear down the hw properly otherwise there
can be problems with the next VM use.
Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Edward O'Callaghan <funfunctor@folklore1984.net>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/radeon_device.c

@@ -639,7 +639,7 @@ void radeon_gtt_location(struct radeon_device *rdev, struct radeon_mc *mc)
  * Used at driver startup.
  * Returns true if virtual or false if not.
  */
-static bool radeon_device_is_virtual(void)
+bool radeon_device_is_virtual(void)
 {
 #ifdef CONFIG_X86
 	return boot_cpu_has(X86_FEATURE_HYPERVISOR);

drivers/gpu/drm/radeon/radeon_drv.c

@@ -310,6 +310,8 @@ MODULE_DEVICE_TABLE(pci, pciidlist);
 
 static struct drm_driver kms_driver;
 
+bool radeon_device_is_virtual(void);
+
 static int radeon_kick_out_firmware_fb(struct pci_dev *pdev)
 {
 	struct apertures_struct *ap;
@@ -363,6 +365,16 @@ radeon_pci_remove(struct pci_dev *pdev)
 	drm_put_dev(dev);
 }
 
+static void
+radeon_pci_shutdown(struct pci_dev *pdev)
+{
+	/* if we are running in a VM, make sure the device
+	 * torn down properly on reboot/shutdown
+	 */
+	if (radeon_device_is_virtual())
+		radeon_pci_remove(pdev);
+}
+
 static int radeon_pmops_suspend(struct device *dev)
 {
 	struct pci_dev *pdev = to_pci_dev(dev);
@@ -583,6 +595,7 @@ static struct pci_driver radeon_kms_pci_driver = {
 	.id_table = pciidlist,
 	.probe = radeon_pci_probe,
 	.remove = radeon_pci_remove,
+	.shutdown = radeon_pci_shutdown,
 	.driver.pm = &radeon_pm_ops,
 };