efi: Correct handling of frame buffer
The efi_gop driver uses private fields from the video uclass to obtain a
pointer to the frame buffer. Use the platform data instead.
Check the VIDEO_COPY setting to determine which frame buffer to use. Once
the next stage is running (and making use of U-Boot's EFI boot services)
U-Boot does not handle copying from priv->fb to the hardware framebuffer,
so we must allow EFI to write directly to the hardware framebuffer.
We could provide a function to read this, but it seems better to just
document how it works. The original change ignored an explicit comment
in the video.h file ("Things that are private to the uclass: don't use
these in the driver") which is why this was missed when the VIDEO_COPY
feature was added.
Signed-off-by: Simon Glass <sjg@chromium.org>
Fixes: 8f661a5b662 ("efi_loader: gop: Expose fb when 32bpp")
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/include/video.h b/include/video.h
index 5048116..4d8df9b 100644
--- a/include/video.h
+++ b/include/video.h
@@ -21,9 +21,12 @@
* @align: Frame-buffer alignment, indicating the memory boundary the frame
* buffer should start on. If 0, 1MB is assumed
* @size: Frame-buffer size, in bytes
- * @base: Base address of frame buffer, 0 if not yet known
- * @copy_base: Base address of a hardware copy of the frame buffer. See
- * CONFIG_VIDEO_COPY.
+ * @base: Base address of frame buffer, 0 if not yet known. If CONFIG_VIDEO_COPY
+ * is enabled, this is the software copy, so writes to this will not be
+ * visible until vidconsole_sync_copy() is called. If CONFIG_VIDEO_COPY is
+ * disabled, this is the hardware framebuffer.
+ * @copy_base: Base address of a hardware copy of the frame buffer. If
+ * CONFIG_VIDEO_COPY is disabled, this is not used.
* @copy_size: Size of copy framebuffer, used if @size is 0
* @hide_logo: Hide the logo (used for testing)
*/