drm/vboxvideo: Use managed interfaces for framebuffer write combining

Replace arch_phys_wc_add() with the rsp managed function. Allows for
removing the cleanup code for memory management
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210916181601.9146-6-tzimmermann@suse.de

drivers/gpu/drm/vboxvideo/vbox_drv.c

@@ -69,7 +69,7 @@ static int vbox_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	ret = vbox_mode_init(vbox);
 	if (ret)
-		goto err_mm_fini;
+		goto err_hw_fini;
 
 	ret = vbox_irq_init(vbox);
 	if (ret)
@@ -87,8 +87,6 @@ static int vbox_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	vbox_irq_fini(vbox);
 err_mode_fini:
 	vbox_mode_fini(vbox);
-err_mm_fini:
-	vbox_mm_fini(vbox);
 err_hw_fini:
 	vbox_hw_fini(vbox);
 	return ret;
@@ -101,7 +99,6 @@ static void vbox_pci_remove(struct pci_dev *pdev)
 	drm_dev_unregister(&vbox->ddev);
 	vbox_irq_fini(vbox);
 	vbox_mode_fini(vbox);
-	vbox_mm_fini(vbox);
 	vbox_hw_fini(vbox);
 }
 

drivers/gpu/drm/vboxvideo/vbox_drv.h

@@ -139,7 +139,6 @@ void vbox_mode_fini(struct vbox_private *vbox);
 void vbox_report_caps(struct vbox_private *vbox);
 
 int vbox_mm_init(struct vbox_private *vbox);
-void vbox_mm_fini(struct vbox_private *vbox);
 
 /* vbox_irq.c */
 int vbox_irq_init(struct vbox_private *vbox);

drivers/gpu/drm/vboxvideo/vbox_ttm.c

@@ -13,22 +13,21 @@
 int vbox_mm_init(struct vbox_private *vbox)
 {
 	int ret;
+	resource_size_t base, size;
 	struct drm_device *dev = &vbox->ddev;
 	struct pci_dev *pdev = to_pci_dev(dev->dev);
 
-	ret = drmm_vram_helper_init(dev, pci_resource_start(pdev, 0),
-				       vbox->available_vram_size);
+	base = pci_resource_start(pdev, 0);
+	size = pci_resource_len(pdev, 0);
+
+	/* Don't fail on errors, but performance might be reduced. */
+	devm_arch_phys_wc_add(&pdev->dev, base, size);
+
+	ret = drmm_vram_helper_init(dev, base, vbox->available_vram_size);
 	if (ret) {
 		DRM_ERROR("Error initializing VRAM MM; %d\n", ret);
 		return ret;
 	}
 
-	vbox->fb_mtrr = arch_phys_wc_add(pci_resource_start(pdev, 0),
-					 pci_resource_len(pdev, 0));
 	return 0;
 }
-
-void vbox_mm_fini(struct vbox_private *vbox)
-{
-	arch_phys_wc_del(vbox->fb_mtrr);
-}