Re: [PATCH] CorebootPayloadPkg: Use correct BytesPerScanLine

[Nico Huber <nico.h@gmx.de>]

Hi Ben,

On 28.01.2018 09:49, You, Benjamin wrote:
> Hi Nico,
> 
> Thanks for the detailed information. It makes sense. I do like the idea of
> documenting the lb_framebuffer.
> 
>> The only guarantee for `bytes_per_pixel` (typo? 'bytes_per_scanline') 

yes, typo.

>> and `x_resolution` you get as a consumer, is that the former is big 
>> enough to hold `x_resolution` pixels.
> 
> I think it would be good to also document that the consumer is assured that
> in framebuffer, all the 'x_resolution' pixels are aligned at the beginning
> of each scanline, and the extra bytes are always padded after the 
> 'x_resolution' pixels in the scanline. Would this be true with existing
> graphics devices? (I am not expert in this area so I'd like to confirm.)

Yes, that's true. I've started to document the whole thing now:

https://review.coreboot.org/#/c/coreboot/+/23466/4/src/commonlib/include/commonlib/coreboot_tables.h@214

The same applies in principle to EFI_GRAPHICS_OUTPUT_MODE_INFORMATION.
This framebuffer layout is very common.

Nico