[coreboot-gerrit] Change in coreboot[master]: mb/google/guybrush: add DXIO and DDI descriptors

[Felix Held (Code Review)]

Attention is currently required from: Marshall Dawson, Nikolai Vyssotski, Matt Papageorge.
Felix Held has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/51957 )

Change subject: mb/google/guybrush: add DXIO and DDI descriptors
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Patch Set 3:

(2 comments)

File src/mainboard/google/guybrush/port_descriptors.c:

https://review.coreboot.org/c/coreboot/+/51957/comment/d753d319_c6e7df84 
PS3, Line 12: .device_number = 0,
> […]

iirc that will automatically select a working configuration. we should provide the values we want here though to be always consistent with the devicetree. but yes, that should be some function of device 2 on bus 0

https://review.coreboot.org/c/coreboot/+/51957/comment/68652a23_a4a911a5 
PS3, Line 55: DDI_DP
> This should be DDI_EDP for Guybrush. Comments are also incorrect.

i took the code from here https://review.coreboot.org/c/coreboot/+/51948/1/src/soc/amd/cezanne/fsp_m_p... haven't checked yet if that matches the hardware