[S] Change in coreboot[master]: soc/amd/*/root_complex: reserve IOMMU MMIO area

[Felix Held (Code Review)]

Attention is currently required from: Arthur Heymans, Fred Reitberger, Jason Glenesk, Matt DeVillier, Raul Rangel.

Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/75611?usp=email )

Change subject: soc/amd/*/root_complex: reserve IOMMU MMIO area
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Patch Set 4:

(2 comments)

Patchset:

PS2:
> need to do this for the other socs too

Done

File src/soc/amd/common/block/include/amdblocks/iomap.h:

https://review.coreboot.org/c/coreboot/+/75611/comment/df15bad6_d63e0517 :
PS4, Line 15: 0xfd00000000
> That's typically where the full SPI flash is mapped too right (ROM3 register)? […]

hmm, i'd need to have a closer look at this next week. somewhere at the beginning of the data fabric chapter the ppr says that most of this area is reserved for the iommu. there are 3 regions that cover more or less the full 4GB region, but might be that something else is in between those