[coreboot-gerrit] Change in ...coreboot[master]: payload/seabios: Fix CBFS location on APL platform

[Aaron Durbin (Code Review)]

Aaron Durbin has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/32327 )

Change subject: payload/seabios: Fix CBFS location on APL platform
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Patch Set 3:

(1 comment)

https://review.coreboot.org/#/c/32327/3/payloads/external/SeaBIOS/Makefile 
File payloads/external/SeaBIOS/Makefile:

https://review.coreboot.org/#/c/32327/3/payloads/external/SeaBIOS/Makefile@4... 
PS3, Line 43: 	echo "CONFIG_CBFS_LOCATION=0xfffc0000" >> seabios/.config
> as only a part of the boot media is memory mapped on x86 (the bios region), and we don't know the si […]

In short, there's a linear translation of physical boot media offsets into physical address space. When the bios region is at the top of the physical boot media it's a straight forward calculation as noted. However, when it isn't then one needs to know size and offset of the bios region to make the proper adjustments. That's what src/soc/intel/apollolake/mmap_boot.c does, as noted by kmalkki.