[coreboot-gerrit] Change in coreboot[master]: lib/edid_fill_fb: Support multiple framebuffers

[Nico Huber (Code Review)]

Attention is currently required from: Patrick Rudolph.
Nico Huber has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/39002 )

Change subject: lib/edid_fill_fb: Support multiple framebuffers
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Patch Set 27:

(1 comment)

File src/lib/edid_fill_fb.c:

https://review.coreboot.org/c/coreboot/+/39002/comment/7bad5014_a5c764e4 
PS27, Line 53: 		       " This is a driver bug.\n", __func__, fb->bits_per_pixel, bpp_mask);
> Here are the supported VESA modes: […]

You may be right. Only now that you called it "reserved fields"
I noticed that we might have misinterpreted VBE for the last (20?)
years. The code always seemed to treat them as fields that describe
reserved bits. Never occured to me that they might have been meant
as reserved fields. And these fields in coreboot seem to be modeled
after VBE...

They are part of an external ABI by now (cf. `coreboot_tables.h`).
So I'd still prefer sanitizing the values. Otherwise we'd be incom-
patible to our own interface :-/

Relaxing the check seems ok, too, how about only bailing out
if the sum is > bits_per_pixel but always logging the error?