[XS] Change in coreboot[main]: drivers/pc80/rtc/mc146818rtc: Add assertion of bank selection for AMD

[Yu-Ping Wu (Code Review)]

Attention is currently required from: Jérémy Compostella, Karthik Ramasubramanian, Paul Menzel, Yu-Ping Wu.

Hello Jérémy Compostella, Karthik Ramasubramanian, Paul Menzel, build bot (Jenkins),

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

https://review.coreboot.org/c/coreboot/+/83537?usp=email

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

Change subject: drivers/pc80/rtc/mc146818rtc: Add assertion of bank selection for AMD
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drivers/pc80/rtc/mc146818rtc: Add assertion of bank selection for AMD

As described in CB:83495, in AMD platforms, the bit 4 of CMOS Register A
is bank selection. Since the MC146818 driver accesses VBNV via Bank 0,
the value set in cmos_init() must not contain that bit.

To prevent RTC_FREQ_SELECT_DEFAULT from being incorrectly modified, add
an static assertion about the bank selection for AMD. Note that the
kernel driver also ensures RTC_AMD_BANK_SELECT isn't set for AMD [1].

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/dr...

BUG=b:346716300
TEST=none
BRANCH=skyrim

Change-Id: I6122201914c40604f86dcca6025b55c595ef609e
Signed-off-by: Yu-Ping Wu 
---
M src/drivers/pc80/rtc/mc146818rtc.c
M src/include/pc80/mc146818rtc.h
2 files changed, 5 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/37/83537/3