[U-Boot] [PATCH 3/3] video: add config option to skip framebuffer clear

[Rob Clark <robdclark@gmail.com>]

The use-case is that the thing that loaded u-boot already put a splash
image on screen.  And we want to preserve that until grub boot menu
takes over.

Signed-off-by: Rob Clark <robdclark@gmail.com>
---
 drivers/video/Kconfig        | 8 ++++++++
 drivers/video/cfb_console.c  | 3 ++-
 drivers/video/video-uclass.c | 4 +++-
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 8eb0359231..7b56b20344 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -98,6 +98,14 @@ config SYS_WHITE_ON_BLACK
 	 better in low-light situations or to reduce eye strain in some
 	 cases.
 
+config NO_FB_CLEAR
+	bool "Skip framebuffer clear"
+	help
+	  If firmware (whatever loads u-boot) has already put a splash image
+	  on screen, you might want to preserve it until whatever u-boots
+	  loads takes over the screen.  This, for example, can be used to
+	  keep splash image on screen until grub graphical boot menu starts.
+
 source "drivers/video/fonts/Kconfig"
 
 config VIDCONSOLE_AS_LCD
diff --git a/drivers/video/cfb_console.c b/drivers/video/cfb_console.c
index f54802052e..85fa5b0cae 100644
--- a/drivers/video/cfb_console.c
+++ b/drivers/video/cfb_console.c
@@ -2091,7 +2091,8 @@ static int cfg_video_init(void)
 	}
 	eorx = fgx ^ bgx;
 
-	video_clear();
+	if (!CONFIG_IS_ENABLED(NO_FB_CLEAR))
+		video_clear();
 
 #ifdef CONFIG_VIDEO_LOGO
 	/* Plot the logo and get start point of console */
diff --git a/drivers/video/video-uclass.c b/drivers/video/video-uclass.c
index 3036e3a1f2..dfa39b0d1b 100644
--- a/drivers/video/video-uclass.c
+++ b/drivers/video/video-uclass.c
@@ -199,7 +199,9 @@ static int video_post_probe(struct udevice *dev)
 #else
 	priv->colour_bg = 0xffffff;
 #endif
-	video_clear(dev);
+
+	if (!CONFIG_IS_ENABLED(NO_FB_CLEAR))
+		video_clear(dev);
 
 	/*
 	 * Create a text console device. For now we always do this, although
-- 
2.13.0