[Patch 1/1] PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe: PcdRtcDefaultYear bounds

["Michael D Kinney" <michael.d.kinney@intel.com>]

Add bounds checks of PcdRtcDefaultYear to guarantee that the year
is always between PcdMinimalValidYear and PcdMaximalValidYear.
This is required to make the following commit a backwards compatible
change and guarantee and invalid year is never set.

https://github.com/tianocore/edk2/commit/d55d73152ebf5c793b645d6ec5bc517d219881cd

This is required because use of an expression in the DEC file
PCD default value is only used to determine the DEC default values.
If an INF/DSC overrides PcdRtcDefaultYear, then the DEC expression
for PcdMinimalValidYear is not applied again.

Cc: Ray Ni <ray.ni@intel.com>
Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com>
---
 PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c b/PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c
index b059e92f02dc..15759463f2a3 100644
--- a/PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c
+++ b/PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c
@@ -317,7 +317,8 @@ PcRtcInit (
     Time.Hour       = RTC_INIT_HOUR;
     Time.Day        = RTC_INIT_DAY;
     Time.Month      = RTC_INIT_MONTH;
-    Time.Year       = PcdGet16 (PcdRtcDefaultYear);
+    Time.Year       = MAX (PcdGet16 (PcdRtcDefaultYear), PcdGet16 (PcdMinimalValidYear));
+    Time.Year       = MIN (Time.Year, PcdGet16 (PcdMaximalValidYear));
     Time.Nanosecond = 0;
     Time.TimeZone   = EFI_UNSPECIFIED_TIMEZONE;
     Time.Daylight   = 0;
@@ -357,7 +358,8 @@ PcRtcInit (
   Time.Hour       = RTC_INIT_HOUR;
   Time.Day        = RTC_INIT_DAY;
   Time.Month      = RTC_INIT_MONTH;
-  Time.Year       = PcdGet16 (PcdRtcDefaultYear);
+  Time.Year       = MAX (PcdGet16 (PcdRtcDefaultYear), PcdGet16 (PcdMinimalValidYear));
+  Time.Year       = MIN (Time.Year, PcdGet16 (PcdMaximalValidYear));
   Time.Nanosecond = 0;
   Time.TimeZone   = Global->SavedTimeZone;
   Time.Daylight   = Global->Daylight;
-- 
2.39.1.windows.1