Change in coreboot[master]: arch/x86/walkcbfs.S: Use FMAP instead of "cbfs master header"

[Arthur Heymans (Code Review)]

Arthur Heymans has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/52879 )

Change subject: arch/x86/walkcbfs.S: Use FMAP instead of "cbfs master header"
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Patch Set 6:

(1 comment)

Patchset:

PS6:
> FYI, this change can break platforms with FMD file containing a statement like "FLASH 8M", because on x86 flash is memory mapped under 4GB. It results in fmap_config.h with "#define FMAP_SECTION_FLASH_START 0" and all offsets to regions relative to zero. There is difference bewteen COREBOOT let's say at 0x400000 and at 0xffc00000. So the correct statement in FMD would be "FLASH@<4GB - flash_size> <flash_size>" like "FLASH@0xff800000 8M". If one does not use any FMD file, the autogenerated fmap_config will contain absolute addresses and it will work with this patch. Just found it out with my Dell Optiplex 9010 and a FMD file with "FLASH 12M" statement.

Thanks for finding this: fixed in CB:55452