Aaron Durbin has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/34805 )
Change subject: arch/x86: Add postcar_frame_add_ramcache() API ......................................................................
Patch Set 1:
(2 comments)
https://review.coreboot.org/c/coreboot/+/34805/1/src/arch/x86/postcar_loader... File src/arch/x86/postcar_loader.c:
https://review.coreboot.org/c/coreboot/+/34805/1/src/arch/x86/postcar_loader... PS1, Line 135: MTRR_TYPE_WRPROT
yeah, WB can't be satisfied option here due to caching issue. (Data region already marked as WB) […]
It's not marked as WB yet. It should be the same type as passed in below. Remember, this function is only for speeding up *loading* of the next stage. Therefore, all it's doing is adding to the MTRR solution for that specific region. Likewise, it's a part of the MTRR solution for postcar once it tears down and re-enables MTRRs with the newly requested set.
https://review.coreboot.org/c/coreboot/+/34805/1/src/arch/x86/postcar_loader... PS1, Line 138: postcar_frame_add_ramcache This name is weird. I think it should reflect that it's top of 32-bit DRAM usage.