drm/ast: Move cursor fb pinning and mapping into helper

The new helper ast_cursor_blit() updates a cursor's backbuffer HW
BO from a framebuffer structure. The cursor plane's prepare_fb()
function now uses the new interface.

Pinning and mapping of BOs is done automatically by the helper. This
includes the source BO, which was not pinned by the original code in
prepare_fb().

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200702115029.5281-4-tzimmermann@suse.de

drivers/gpu/drm/ast/ast_cursor.c

@@ -140,8 +140,8 @@ static u32 copy_cursor_image(u8 *src, u8 *dst, int width, int height)
 	return csum;
 }
 
-int ast_cursor_update(void *dst, void *src, unsigned int width,
-		      unsigned int height)
+static int ast_cursor_update(void *dst, void *src, unsigned int width,
+			     unsigned int height)
 {
 	u32 csum;
 
@@ -159,6 +159,59 @@ int ast_cursor_update(void *dst, void *src, unsigned int width,
 	return 0;
 }
 
+int ast_cursor_blit(struct ast_private *ast, struct drm_framebuffer *fb)
+{
+	struct drm_device *dev = ast->dev;
+	struct drm_gem_vram_object *gbo;
+	int ret;
+	void *src;
+	void *dst;
+
+	if (drm_WARN_ON_ONCE(dev, fb->width > AST_MAX_HWC_WIDTH) ||
+	    drm_WARN_ON_ONCE(dev, fb->height > AST_MAX_HWC_HEIGHT))
+		return -EINVAL;
+
+	gbo = drm_gem_vram_of_gem(fb->obj[0]);
+
+	ret = drm_gem_vram_pin(gbo, 0);
+	if (ret)
+		return ret;
+	src = drm_gem_vram_vmap(gbo);
+	if (IS_ERR(src)) {
+		ret = PTR_ERR(src);
+		goto err_drm_gem_vram_unpin;
+	}
+
+	dst = drm_gem_vram_vmap(ast->cursor.gbo[ast->cursor.next_index]);
+	if (IS_ERR(dst)) {
+		ret = PTR_ERR(dst);
+		goto err_drm_gem_vram_vunmap_src;
+	}
+
+	ret = ast_cursor_update(dst, src, fb->width, fb->height);
+	if (ret)
+		goto err_drm_gem_vram_vunmap_dst;
+
+	/*
+	 * Always unmap buffers here. Destination buffers are
+	 * perma-pinned while the driver is active. We're only
+	 * changing ref-counters here.
+	 */
+	drm_gem_vram_vunmap(ast->cursor.gbo[ast->cursor.next_index], dst);
+	drm_gem_vram_vunmap(gbo, src);
+	drm_gem_vram_unpin(gbo);
+
+	return 0;
+
+err_drm_gem_vram_vunmap_dst:
+	drm_gem_vram_vunmap(ast->cursor.gbo[ast->cursor.next_index], dst);
+err_drm_gem_vram_vunmap_src:
+	drm_gem_vram_vunmap(gbo, src);
+err_drm_gem_vram_unpin:
+	drm_gem_vram_unpin(gbo);
+	return ret;
+}
+
 void ast_cursor_set_base(struct ast_private *ast, u64 address)
 {
 	u8 addr0 = (address >> 3) & 0xff;

drivers/gpu/drm/ast/ast_drv.h

@@ -318,8 +318,7 @@ void ast_release_firmware(struct drm_device *dev);
 /* ast_cursor.c */
 int ast_cursor_init(struct ast_private *ast);
 void ast_cursor_fini(struct ast_private *ast);
-int ast_cursor_update(void *dst, void *src, unsigned int width,
-		      unsigned int height);
+int ast_cursor_blit(struct ast_private *ast, struct drm_framebuffer *fb);
 void ast_cursor_set_base(struct ast_private *ast, u64 address);
 int ast_cursor_move(struct drm_crtc *crtc, int x, int y);
 

drivers/gpu/drm/ast/ast_mode.c

@@ -611,56 +611,21 @@ static int
 ast_cursor_plane_helper_prepare_fb(struct drm_plane *plane,
 				   struct drm_plane_state *new_state)
 {
-	struct drm_device *dev = plane->dev;
 	struct drm_framebuffer *fb = new_state->fb;
 	struct drm_crtc *crtc = new_state->crtc;
-	struct drm_gem_vram_object *gbo;
 	struct ast_private *ast;
 	int ret;
-	void *src, *dst;
 
 	if (!crtc || !fb)
 		return 0;
 
-	if (drm_WARN_ON_ONCE(dev, fb->width > AST_MAX_HWC_WIDTH) ||
-	    drm_WARN_ON_ONCE(dev, fb->height > AST_MAX_HWC_HEIGHT))
-		return -EINVAL; /* BUG: didn't test in atomic_check() */
+	ast = to_ast_private(plane->dev);
 
-	ast = to_ast_private(dev);
-
-	gbo = drm_gem_vram_of_gem(fb->obj[0]);
-	src = drm_gem_vram_vmap(gbo);
-	if (IS_ERR(src)) {
-		ret = PTR_ERR(src);
-		goto err_drm_gem_vram_unpin;
-	}
-
-	dst = drm_gem_vram_vmap(ast->cursor.gbo[ast->cursor.next_index]);
-	if (IS_ERR(dst)) {
-		ret = PTR_ERR(dst);
-		goto err_drm_gem_vram_vunmap_src;
-	}
-
-	ret = ast_cursor_update(dst, src, fb->width, fb->height);
+	ret = ast_cursor_blit(ast, fb);
 	if (ret)
-		goto err_drm_gem_vram_vunmap_dst;
-
-	/* Always unmap buffers here. Destination buffers are
-	 * perma-pinned while the driver is active. We're only
-	 * changing ref-counters here.
-	 */
-	drm_gem_vram_vunmap(ast->cursor.gbo[ast->cursor.next_index], dst);
-	drm_gem_vram_vunmap(gbo, src);
+		return ret;
 
 	return 0;
-
-err_drm_gem_vram_vunmap_dst:
-	drm_gem_vram_vunmap(ast->cursor.gbo[ast->cursor.next_index], dst);
-err_drm_gem_vram_vunmap_src:
-	drm_gem_vram_vunmap(gbo, src);
-err_drm_gem_vram_unpin:
-	drm_gem_vram_unpin(gbo);
-	return ret;
 }
 
 static int ast_cursor_plane_helper_atomic_check(struct drm_plane *plane,