x86: video: Support copy framebuffer with probed devices
For PCI video devices that are not mentioned in the devicetree, U-Boot
does not bind a driver before relocation, since PCI is not fully probed
at that point. Furthermore it is possible for the video device to be on
a secondary bus which is not even scanned.
This is fine if the framebuffer is allocated in fixed memory, as it
normally is on x86. But when using this as a copy framebuffer, we also
need U-Boot to allocate its own cached framebuffer for working in. Since
the video driver is never bound before relocation, the framebuffer size
is never set and U-Boot does no allocation.
Add a new CONFIG option to reserve 16MB of memory for this eventuality.
This allows vesa devices to use the copy framebuffer.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Anatolij Gustschin <agust@denx.de>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/drivers/video/video-uclass.c b/drivers/video/video-uclass.c
index 4735a22..650891e 100644
--- a/drivers/video/video-uclass.c
+++ b/drivers/video/video-uclass.c
@@ -97,6 +97,11 @@
debug("%s: Reserving %lx bytes at %lx for video device '%s'\n",
__func__, size, *addrp, dev->name);
}
+
+ /* Allocate space for PCI video devices in case there were not bound */
+ if (*addrp == gd->video_top)
+ *addrp -= CONFIG_VIDEO_PCI_DEFAULT_FB_SIZE;
+
gd->video_bottom = *addrp;
gd->fb_base = *addrp;
debug("Video frame buffers from %lx to %lx\n", gd->video_bottom,