Zhuoran: Ray is the maintainer of PcAtChipsetPkg. Can you collect his feedback on this change?
Thanks Liming > -----邮件原件----- > 发件人: devel@edk2.groups.io <devel@edk2.groups.io> 代表 Zhuoran Chao > 发送时间: 2022年4月29日 13:43 > 收件人: devel@edk2.groups.io; Gao, Liming <gaolim...@byosoft.com.cn> > 抄送: Ni, Ray <ray...@intel.com> > 主题: Re: [edk2-devel] [PATCH] PcAtChipsetPkg: Change the flow of > PcRtcInit() > > Hi Liming: > Could you help to give a nudge on the below issue because it is related to a > bug fixing of Intel server platform enabling team. > > Thanks > Zhuoran > > -----Original Message----- > From: Chao, Zhuoran <zhuoran.c...@intel.com> > Sent: Monday, April 25, 2022 11:47 PM > To: devel@edk2.groups.io > Cc: Chao, Zhuoran <zhuoran.c...@intel.com>; Ni, Ray <ray...@intel.com> > Subject: [PATCH] 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. > > Cc: Ray Ni <ray...@intel.com> > > Signed-off-by: Zhuoran Chao <zhuoran.c...@intel.com> > --- > PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c | 14 +++++++------- > 1 file changed, 7 insertions(+), 7 deletions(-) > > diff --git a/PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c > b/PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c > index 0fbfa4bcee..ea56a66267 100644 > --- a/PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c > +++ b/PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c > @@ -269,13 +269,6 @@ PcRtcInit ( > Time.Month = RtcRead (RTC_ADDRESS_MONTH); > Time.Year = RtcRead (RTC_ADDRESS_YEAR); > > - // > - // Set RTC configuration after get original time > - // The value of bit AIE should be reserved. > - // > - RegisterB.Data = FixedPcdGet8 (PcdInitialValueRtcRegisterB) | > (RegisterB.Data & BIT5); > - RtcWrite (RTC_ADDRESS_REGISTER_B, RegisterB.Data); > - > // > // Release RTC Lock. > // > @@ -330,6 +323,13 @@ PcRtcInit ( > Time.Daylight = 0; > } > > + // > + // Set RTC configuration after get original time // The value of bit > + AIE should be reserved. > + // > + RegisterB.Data = FixedPcdGet8 (PcdInitialValueRtcRegisterB) | > + (RegisterB.Data & BIT5); RtcWrite (RTC_ADDRESS_REGISTER_B, > + RegisterB.Data); > + > // > // Reset time value according to new RTC configuration > // > -- > 2.31.1.windows.1 > > > > > -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#89385): https://edk2.groups.io/g/devel/message/89385 Mute This Topic: https://groups.io/mt/90771085/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
