[U-Boot] [PATCH v5 046/101] x86: fsp: Set up an MTRR for the graphics frame buffer

Simon Glass sjg at chromium.org
Mon Nov 25 04:09:56 UTC 2019

The FSP-S may do this but at least for coral it does not. Set this up so
that graphics is not deathly slow.

It isn't clear whether the FSP is expected to set up MTRR. It is not
mentioned in the APL FSP document.

Signed-off-by: Simon Glass <sjg at chromium.org>
Reviewed-by: Bin Meng <bmeng.cn at gmail.com>

Changes in v5: None
Changes in v4: None
Changes in v3: None
Changes in v2: None

 arch/x86/lib/fsp/fsp_graphics.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/x86/lib/fsp/fsp_graphics.c b/arch/x86/lib/fsp/fsp_graphics.c
index 91d2d08557..226c7e66b3 100644
--- a/arch/x86/lib/fsp/fsp_graphics.c
+++ b/arch/x86/lib/fsp/fsp_graphics.c
@@ -8,6 +8,7 @@
 #include <vbe.h>
 #include <video.h>
 #include <asm/fsp/fsp_support.h>
+#include <asm/mtrr.h>
@@ -97,6 +98,9 @@ static int fsp_video_probe(struct udevice *dev)
 	if (ret)
 		goto err;
+	mtrr_add_request(MTRR_TYPE_WRCOMB, vesa->phys_base_ptr, 256 << 20);
+	mtrr_commit(true);
 	printf("%dx%dx%d\n", uc_priv->xsize, uc_priv->ysize,

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