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PcAtChipsetPkg/PcRtc: Fix a Y2K bug

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The original driver cannot handle the case when system time runs from 1999/12/31 23:59:59
to 2000/1/1 0:0:0.
A simple test to set system time to 1999/12/31 23:59:59 can expose this bug.
The patch limits the driver to only support year in 100 range and decide the century value based
on the supporting range: Century either equals to PcdMinimalYear / 100 or equals to PcdMinimalYear / 100 + 1.

The patch passed the Y2K test.
However with year range [1998, 2097], when system time is 2097/12/31 23:59:59,
the next second system time will become 1998/1/1 0:0:0. I think it's a acceptable limitation.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@17624 6f19259b-4bc3-4df7-8a09-765794883524
This commit is contained in:
Ruiyu Ni
2015-06-11 07:14:18 +00:00
committed by niruiyu
parent e63ec1beac
commit fe32096778
3 changed files with 27 additions and 44 deletions
Download Patch File Download Diff File Expand all files Collapse all files

55
PcAtChipsetPkg/PcatRealTimeClockRuntimeDxe/PcRtc.c
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@@ -100,7 +100,6 @@ PcRtcInit (
RTC_REGISTER_A RegisterA;
RTC_REGISTER_B RegisterB;
RTC_REGISTER_D RegisterD;
UINT8 Century;
EFI_TIME Time;
UINTN DataSize;
UINT32 TimerVar;
@@ -163,8 +162,6 @@ PcRtcInit (
Time.Month = RtcRead (RTC_ADDRESS_MONTH);
Time.Year = RtcRead (RTC_ADDRESS_YEAR);
Century = RtcRead (RTC_ADDRESS_CENTURY);
//
// Set RTC configuration after get original time
// The value of bit AIE should be reserved.
@@ -201,7 +198,7 @@ PcRtcInit (
//
// Validate time fields
//
Status = ConvertRtcTimeToEfiTime (&Time, Century, RegisterB);
Status = ConvertRtcTimeToEfiTime (&Time, RegisterB);
if (!EFI_ERROR (Status)) {
Status = RtcTimeFieldsValid (&Time);
}
@@ -218,7 +215,7 @@ PcRtcInit (
Time.Hour = RTC_INIT_HOUR;
Time.Day = RTC_INIT_DAY;
Time.Month = RTC_INIT_MONTH;
Time.Year = RTC_INIT_YEAR;
Time.Year = PcdGet16 (PcdMinimalValidYear);
Time.Nanosecond = 0;
Time.TimeZone = EFI_UNSPECIFIED_TIMEZONE;
Time.Daylight = 0;
@@ -251,7 +248,7 @@ PcRtcInit (
Time.Hour = RTC_INIT_HOUR;
Time.Day = RTC_INIT_DAY;
Time.Month = RTC_INIT_MONTH;
Time.Year = RTC_INIT_YEAR;
Time.Year = PcdGet16 (PcdMinimalValidYear);
Time.Nanosecond = 0;
Time.TimeZone = Global->SavedTimeZone;
Time.Daylight = Global->Daylight;;
@@ -272,8 +269,8 @@ PcRtcInit (
}
return EFI_DEVICE_ERROR;
}
ConvertEfiTimeToRtcTime (&Time, RegisterB, &Century);
ConvertEfiTimeToRtcTime (&Time, RegisterB);
//
// Set the Y/M/D info to variable as it has no corresponding hw registers.
@@ -343,7 +340,6 @@ PcRtcGetTime (
{
EFI_STATUS Status;
RTC_REGISTER_B RegisterB;
UINT8 Century;
//
// Check parameters for null pointer
@@ -383,8 +379,6 @@ PcRtcGetTime (
Time->Month = RtcRead (RTC_ADDRESS_MONTH);
Time->Year = RtcRead (RTC_ADDRESS_YEAR);
Century = RtcRead (RTC_ADDRESS_CENTURY);
//
// Release RTC Lock.
//
@@ -401,7 +395,7 @@ PcRtcGetTime (
//
// Make sure all field values are in correct range
//
Status = ConvertRtcTimeToEfiTime (Time, Century, RegisterB);
Status = ConvertRtcTimeToEfiTime (Time, RegisterB);
if (!EFI_ERROR (Status)) {
Status = RtcTimeFieldsValid (Time);
}
@@ -447,7 +441,6 @@ PcRtcSetTime (
EFI_STATUS Status;
EFI_TIME RtcTime;
RTC_REGISTER_B RegisterB;
UINT8 Century;
UINT32 TimerVar;
if (Time == NULL) {
@@ -506,7 +499,7 @@ PcRtcSetTime (
RegisterB.Bits.Set = 1;
RtcWrite (RTC_ADDRESS_REGISTER_B, RegisterB.Data);
ConvertEfiTimeToRtcTime (&RtcTime, RegisterB, &Century);
ConvertEfiTimeToRtcTime (&RtcTime, RegisterB);
RtcWrite (RTC_ADDRESS_SECONDS, RtcTime.Second);
RtcWrite (RTC_ADDRESS_MINUTES, RtcTime.Minute);
@@ -514,7 +507,6 @@ PcRtcSetTime (
RtcWrite (RTC_ADDRESS_DAY_OF_THE_MONTH, RtcTime.Day);
RtcWrite (RTC_ADDRESS_MONTH, RtcTime.Month);
RtcWrite (RTC_ADDRESS_YEAR, (UINT8) RtcTime.Year);
RtcWrite (RTC_ADDRESS_CENTURY, Century);
//
// Allow updates of the RTC registers
@@ -564,7 +556,6 @@ PcRtcGetWakeupTime (
EFI_STATUS Status;
RTC_REGISTER_B RegisterB;
RTC_REGISTER_C RegisterC;
UINT8 Century;
EFI_TIME RtcTime;
UINTN DataSize;
@@ -612,8 +603,6 @@ PcRtcGetWakeupTime (
Time->TimeZone = Global->SavedTimeZone;
Time->Daylight = Global->Daylight;
Century = RtcRead (RTC_ADDRESS_CENTURY);
//
// Get the alarm info from variable
//
@@ -644,7 +633,7 @@ PcRtcGetWakeupTime (
//
// Make sure all field values are in correct range
//
Status = ConvertRtcTimeToEfiTime (Time, Century, RegisterB);
Status = ConvertRtcTimeToEfiTime (Time, RegisterB);
if (!EFI_ERROR (Status)) {
Status = RtcTimeFieldsValid (Time);
}
@@ -680,7 +669,6 @@ PcRtcSetWakeupTime (
EFI_STATUS Status;
EFI_TIME RtcTime;
RTC_REGISTER_B RegisterB;
UINT8 Century;
EFI_TIME_CAPABILITIES Capabilities;
ZeroMem (&RtcTime, sizeof (RtcTime));
@@ -736,7 +724,7 @@ PcRtcSetWakeupTime (
RegisterB.Data = RtcRead (RTC_ADDRESS_REGISTER_B);
if (Enable) {
ConvertEfiTimeToRtcTime (&RtcTime, RegisterB, &Century);
ConvertEfiTimeToRtcTime (&RtcTime, RegisterB);
} else {
//
// if the alarm is disable, record the current setting.
@@ -837,7 +825,6 @@ CheckAndConvertBcd8ToDecimal8 (
@param Time On input, the time data read from RTC to convert
On output, the time converted to UEFI format
@param Century Value of century read from RTC.
@param RegisterB Value of Register B of RTC, indicating data mode
and hour format.
@@ -848,11 +835,11 @@ CheckAndConvertBcd8ToDecimal8 (
EFI_STATUS
ConvertRtcTimeToEfiTime (
IN OUT EFI_TIME *Time,
IN UINT8 Century,
IN RTC_REGISTER_B RegisterB
)
{
BOOLEAN IsPM;
UINT8 Century;
if ((Time->Hour & 0x80) != 0) {
IsPM = TRUE;
@@ -870,14 +857,21 @@ ConvertRtcTimeToEfiTime (
Time->Minute = CheckAndConvertBcd8ToDecimal8 (Time->Minute);
Time->Second = CheckAndConvertBcd8ToDecimal8 (Time->Second);
}
Century = CheckAndConvertBcd8ToDecimal8 (Century);
if (Time->Year == 0xff || Time->Month == 0xff || Time->Day == 0xff ||
Time->Hour == 0xff || Time->Minute == 0xff || Time->Second == 0xff ||
Century == 0xff) {
Time->Hour == 0xff || Time->Minute == 0xff || Time->Second == 0xff) {
return EFI_INVALID_PARAMETER;
}
//
// For minimal/maximum year range [1970, 2069],
// Century is 19 if RTC year >= 70,
// Century is 20 otherwise.
//
Century = (UINT8) (PcdGet16 (PcdMinimalValidYear) / 100);
if (Time->Year < PcdGet16 (PcdMinimalValidYear) % 100) {
Century++;
}
Time->Year = (UINT16) (Century * 100 + Time->Year);
//
@@ -1053,14 +1047,11 @@ IsLeapYear (
@param Time On input, the time data read from UEFI to convert
On output, the time converted to RTC format
@param RegisterB Value of Register B of RTC, indicating data mode
@param Century It is set according to EFI_TIME Time.
**/
VOID
ConvertEfiTimeToRtcTime (
IN OUT EFI_TIME *Time,
IN RTC_REGISTER_B RegisterB,
OUT UINT8 *Century
IN RTC_REGISTER_B RegisterB
)
{
BOOLEAN IsPM;
@@ -1081,10 +1072,8 @@ ConvertEfiTimeToRtcTime (
}
}
//
// Set the Time/Date/Daylight Savings values.
// Set the Time/Date values.
//
*Century = DecimalToBcd8 ((UINT8) (Time->Year / 100));
Time->Year = (UINT16) (Time->Year % 100);
if (RegisterB.Bits.Dm == 0) {