[S] Change in coreboot[main]: sb/intel/bd82x6x: Follow PCH BIOS spec

[Patrick Rudolph (Code Review)]

Attention is currently required from: Kyösti Mälkki, Patrick Rudolph.

Hello Kyösti Mälkki, build bot (Jenkins),

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/78225?usp=email

to look at the new patch set (#3).

The following approvals got outdated and were removed:
Code-Review+2 by Kyösti Mälkki, Verified+1 by build bot (Jenkins)

The change is no longer submittable: Code-Review and Verified are unsatisfied now.

Change subject: sb/intel/bd82x6x: Follow PCH BIOS spec
......................................................................

sb/intel/bd82x6x: Follow PCH BIOS spec

PCH BIOS spec says that BIOS must clear BIT26 in register 0x338
in PEI, as done on lynxpoint.
Copy and adapt the lynxpoint code to do the same on bd82x6x.
Add special case for UM77 chipset, which only has 4 PCIe ports.

Test: System still boots and all PCIe ports are fully working.

Change-Id: I865818c0c22194fffcb2bbdf8c43737b0dce2307
Signed-off-by: Patrick Rudolph 
---
M src/southbridge/intel/bd82x6x/early_pch.c
M src/southbridge/intel/bd82x6x/pch.h
2 files changed, 10 insertions(+), 1 deletion(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/25/78225/3