| From 587dd959fc82bc20c944c05caa7bc606046a7e34 Mon Sep 17 00:00:00 2001 |
| From: Marc Jones <marc.jones@scarletltd.com> |
| Date: Wed, 6 Jun 2018 12:05:58 -0600 |
| Subject: [PATCH] PcAtChipsetPkg: Maintain the RTC VRT bit |
| |
| AMD SCO RTC VRT bit is updated every 256ms. The RTC logic |
| clears the bit when writing RegD. It then checks the bit to see if |
| the RTC is OK after a 10ms timeout and fails when it isn't set. We could |
| change the timeout, but that would delay the boot unnecessarily. Maintain |
| the VRT bit as it is updated regularly and carry on. |
| |
| Signed-off-by: Marc Jones <marc.jones@scarletltd.com> |
| --- |
| PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c | 5 ++++- |
| 1 file changed, 4 insertions(+), 1 deletion(-) |
| |
| diff --git a/PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c b/PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c |
| index 857918d..08c644a 100644 |
| --- a/PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c |
| +++ b/PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c |
| @@ -143,8 +143,11 @@ PcRtcInit ( |
|
|
| //
|
| // Clear RTC register D
|
| + // AMD workaround - Don't clear the VRT bit
|
| //
|
| - RegisterD.Data = RTC_INIT_REGISTER_D;
|
| + RegisterD.Data = RtcRead (RTC_ADDRESS_REGISTER_D);
|
| + RegisterD.Bits.Reserved = 0; // Maintain RegisterD.Bits.Vrt
|
| + RegisterD.Data |= RTC_INIT_REGISTER_D;
|
| RtcWrite (RTC_ADDRESS_REGISTER_D, RegisterD.Data);
|
|
|
| //
|
| -- |
| 2.7.4 |
| |
