[S] Change in coreboot[master]: soc/intel/alderlake: Hook up PchHdaAudioLinkHdaEnable to devicetree

[Michał Żygowski (Code Review)]

Attention is currently required from: Sean Rhodes, Nico Huber, Tarun Tuli, Subrata Banik, Paul Menzel, Arthur Heymans, Eric Lai.

Michał Żygowski has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/71715 )

Change subject: soc/intel/alderlake: Hook up PchHdaAudioLinkHdaEnable to devicetree
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Patch Set 4:

(1 comment)

Patchset:

PS4:
> SDI1 doesn't make any difference to me. […]

@Eric the SDI GPIOs is not the only point that ensures proper HDA operation.

In the mentioned PeiCavsInitLib there is a line:

HdaCallbacks->HdaPcrPidDspAndThenOr32 (R_HDA_PCR_CDCCFG, (UINT32)~0, (B_HDA_PCR_CDCCFG_DIS_SDIN0 | B_HDA_PCR_CDCCFG_DIS_SDIN1));

that will be executed if (HdaPreMemConfig->AudioLinkHda.Enable == FALSE)

else if (HdaPreMemConfig->AudioLinkHda.Enable == TRUE) AND (HdaPreMemConfig->AudioLinkHda.SdiEnable[0] == FALSE) then

HdaCallbacks->HdaPcrPidDspAndThenOr32 (R_HDA_PCR_CDCCFG, (UINT32)~0, (B_HDA_PCR_CDCCFG_DIS_SDIN0));

is executed, effectively disabling SDI pins in the HDA private configuration space.

To be clear:

HdaPreMemConfig->AudioLinkHda.Enable = FspmUpd->FspmConfig.PchHdaAudioLinkHdaEnable;
HdaPreMemConfig->AudioLinkHda.SdiEnable[Index] = FspmUpd->FspmConfig.PchHdaSdiEnable[Index];

That is why we need PchHdaAudioLinkHdaEnable and PchHdaSdiEnable to be board-controllable. By default PchHdaSdiEnable[0] and PchHdaAudioLinkHdaEnable UPDs are set to enabled, but coreboot overrides them to disabled in soc code, which make HDA non-functional in my and Sean's cases.