Change in coreboot[master]: lib/edid_fill_fb: Relax bits_per_pixel constraint

[Nico Huber (Code Review)]

Nico Huber has submitted this change. ( https://review.coreboot.org/c/coreboot/+/49404 )

Change subject: lib/edid_fill_fb: Relax bits_per_pixel constraint
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lib/edid_fill_fb: Relax bits_per_pixel constraint

The Picasso VBIOS is not setting the reserved_mask_size correctly. This
change relaxes the constraint to allow bpp_mask <= bits_per_pixel. This
is how the code previously used to work before CB:39002.

BUG=b:177094598, b:177422379
TEST=boot zork and see depthcharge working

Signed-off-by: Raul E Rangel 
Change-Id: I2e67532fa949fbd673269d8d7f1c0d8af6124ac9
Reviewed-on: https://review.coreboot.org/c/coreboot/+/49404
Tested-by: build bot (Jenkins) 
Reviewed-by: Nico Huber 
Reviewed-by: Angel Pons 
Reviewed-by: Yu-Ping Wu 
---
M src/lib/edid_fill_fb.c
1 file changed, 10 insertions(+), 3 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Nico Huber: Looks good to me, approved
  Angel Pons: Looks good to me, but someone else must approve
  Yu-Ping Wu: Looks good to me, approved

diff --git a/src/lib/edid_fill_fb.c b/src/lib/edid_fill_fb.c
index 712cd0f..7e8aa95 100644
--- a/src/lib/edid_fill_fb.c
+++ b/src/lib/edid_fill_fb.c
@@ -48,10 +48,17 @@

bpp_mask = fb->blue_mask_size + fb->green_mask_size + fb->red_mask_size +
    	fb->reserved_mask_size;
-	if (fb->bits_per_pixel != bpp_mask) {
-		printk(BIOS_ERR, "%s: BPP=%d and channel bit mask=%d doesn't match."
-		       " This is a driver bug.\n", __func__, fb->bits_per_pixel, bpp_mask);
+	if (bpp_mask > fb->bits_per_pixel) {
+		printk(BIOS_ERR,
+		       "%s: channel bit mask=%d is greater than BPP=%d ."
+		       " This is a driver bug. Framebuffer is invalid.\n",
+		       __func__, bpp_mask, fb->bits_per_pixel);
    	return NULL;
+	} else if (bpp_mask != fb->bits_per_pixel) {
+		printk(BIOS_WARNING,
+		       "%s: channel bit mask=%d and BPP=%d don't match."
+		       " This is a driver bug.\n",
+		       __func__, bpp_mask, fb->bits_per_pixel);
    }

info = fb_new_framebuffer_info();