1 files changed, 29 insertions, 25 deletions

diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c
index 21715d6a9b56..b79f484e9bd2 100644
--- a/drivers/gpu/drm/ast/ast_main.c
+++ b/drivers/gpu/drm/ast/ast_main.c
@@ -28,6 +28,7 @@
 
 #include <linux/pci.h>
 
+#include <drm/drm_atomic_helper.h>
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_fb_helper.h>
 #include <drm/drm_gem.h>
@@ -387,8 +388,33 @@ static int ast_get_dram_info(struct drm_device *dev)
 	return 0;
 }
 
+enum drm_mode_status ast_mode_config_mode_valid(struct drm_device *dev,
+						const struct drm_display_mode *mode)
+{
+	static const unsigned long max_bpp = 4; /* DRM_FORMAT_XRGBA8888 */
+
+	struct ast_private *ast = dev->dev_private;
+	unsigned long fbsize, fbpages, max_fbpages;
+
+	/* To support double buffering, a framebuffer may not
+	 * consume more than half of the available VRAM.
+	 */
+	max_fbpages = (ast->vram_size / 2) >> PAGE_SHIFT;
+
+	fbsize = mode->hdisplay * mode->vdisplay * max_bpp;
+	fbpages = DIV_ROUND_UP(fbsize, PAGE_SIZE);
+
+	if (fbpages > max_fbpages)
+		return MODE_MEM;
+
+	return MODE_OK;
+}
+
 static const struct drm_mode_config_funcs ast_mode_funcs = {
-	.fb_create = drm_gem_fb_create
+	.fb_create = drm_gem_fb_create,
+	.mode_valid = ast_mode_config_mode_valid,
+	.atomic_check = drm_atomic_helper_check,
+	.atomic_commit = drm_atomic_helper_commit,
 };
 
 static u32 ast_get_vram_info(struct drm_device *dev)
@@ -506,6 +532,8 @@ int ast_driver_load(struct drm_device *dev, unsigned long flags)
 	if (ret)
 		goto out_free;
 
+	drm_mode_config_reset(dev);
+
 	ret = drm_fbdev_generic_setup(dev, 32);
 	if (ret)
 		goto out_free;
@@ -535,27 +563,3 @@ void ast_driver_unload(struct drm_device *dev)
 	pci_iounmap(dev->pdev, ast->regs);
 	kfree(ast);
 }
-
-int ast_gem_create(struct drm_device *dev,
-		   u32 size, bool iskernel,
-		   struct drm_gem_object **obj)
-{
-	struct drm_gem_vram_object *gbo;
-	int ret;
-
-	*obj = NULL;
-
-	size = roundup(size, PAGE_SIZE);
-	if (size == 0)
-		return -EINVAL;
-
-	gbo = drm_gem_vram_create(dev, &dev->vram_mm->bdev, size, 0, false);
-	if (IS_ERR(gbo)) {
-		ret = PTR_ERR(gbo);
-		if (ret != -ERESTARTSYS)
-			DRM_ERROR("failed to allocate GEM object\n");
-		return ret;
-	}
-	*obj = &gbo->bo.base;
-	return 0;
-}