audk/PcAtChipsetPkg
Chao, Zhuoran 29ae55a0b8 PcAtChipsetPkg: Change the flow of PcRtcInit()
REF:https://bugzilla.tianocore.org/show_bug.cgi?id=3913

The original flow of PcRtcInit() is like:
1. Guarantee atomic accesses to the RTC time registers and
   read out the value.
2. Program RTC register B. (adopt 12h mode or 24h mode. Current
   bios code sets RTC to 24h mode by default).
3. Then function ConvertRtcTimeToEfiTime converts the RTC time
   value to their 24h mode by checking the hour format bit
   (1:24h mode,0:12h mode).
And here lies the problem: Step3 will fail to adjust the value
if Step2 already sets RTC to 24h mode. The hour value in 12h mode
will not be converted to its 24h mode.
The solution is to program RTC register B a little later when all
the original RTC registers' value is retrieved, adjusted
and validated.

ConvertRtcTimeToEfiTime is modified to be more robust.

Reviewed-by: Ray Ni <ray.ni@intel.com>

Signed-off-by: Zhuoran Chao <zhuoran.chao@intel.com>
2022-05-09 02:45:01 +00:00
..
Bus/Pci/IdeControllerDxe PcAtChipsetPkg: Apply uncrustify changes 2021-12-07 17:24:28 +00:00
HpetTimerDxe PcAtChipsetPkg: Apply uncrustify changes 2021-12-07 17:24:28 +00:00
Include PcAtChipsetPkg: Apply uncrustify changes 2021-12-07 17:24:28 +00:00
Library PcAtChipsetPkg: Apply uncrustify changes 2021-12-07 17:24:28 +00:00
PcatRealTimeClockRuntimeDxe PcAtChipsetPkg: Change the flow of PcRtcInit() 2022-05-09 02:45:01 +00:00
PcAtChipsetPkg.ci.yaml PcAtChipsetPkg/PcAtChipsetPkg.ci.yaml: Add configuration for Ecc check 2020-08-17 03:28:09 +00:00
PcAtChipsetPkg.dec PcAtChipsetPkg: Add MMIO Support to RTC driver 2020-10-16 17:21:04 +00:00
PcAtChipsetPkg.dsc PcAtChipsetPkg: Consume MdeLibs.dsc.inc for RegisterFilterLib 2021-03-31 05:47:10 +00:00
PcAtChipsetPkg.uni PcAtChipsetPkg: add PcdRealTimeClockUpdateTimeout 2019-09-04 02:06:25 +08:00
PcAtChipsetPkgExtra.uni PcAtChipsetPkg: Replace BSD License with BSD+Patent License 2019-04-09 10:58:20 -07:00