realtimeclock.c

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  return EFI_SUCCESS;
}

EFI_STATUS
EFIAPI
PcRtcSetWakeupTime (
  IN BOOLEAN                Enable,
  OUT EFI_TIME              *Time,
  IN PC_RTC_MODULE_GLOBALS  *Global
  )
/*++

Routine Description:

  Arguments:

  

Returns: 
--*/
// TODO:    Enable - add argument and description to function comment
// TODO:    Time - add argument and description to function comment
// TODO:    Global - add argument and description to function comment
// TODO:    EFI_INVALID_PARAMETER - add return value to function comment
// TODO:    EFI_INVALID_PARAMETER - add return value to function comment
// TODO:    EFI_UNSUPPORTED - add return value to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  EFI_STATUS            Status;
  EFI_TIME              RtcTime;
  RTC_REGISTER_B        RegisterB;
  UINT8                 Century;
  EFI_TIME_CAPABILITIES Capabilities;

  if (Enable) {

    if (Time == NULL) {
      return EFI_INVALID_PARAMETER;
    }
    //
    // Make sure that the time fields are valid
    //
    Status = RtcTimeFieldsValid (Time);
    if (EFI_ERROR (Status)) {
      return EFI_INVALID_PARAMETER;
    }
    //
    // Just support set alarm time within 24 hours
    //
    PcRtcGetTime (&RtcTime, &Capabilities, Global);
    if (!IsWithinOneDay (&RtcTime, Time)) {
      return EFI_UNSUPPORTED;
    }
    //
    // Make a local copy of the time and date
    //
    EfiCopyMem (&RtcTime, Time, sizeof (EFI_TIME));

  }
  //
  // Acquire RTC Lock to make access to RTC atomic
  //
  EfiAcquireLock (&Global->RtcLock);

  //
  // Wait for up to 0.1 seconds for the RTC to be updated
  //
  Status = RtcWaitToUpdate (100000);
  if (EFI_ERROR (Status)) {
    EfiReleaseLock (&Global->RtcLock);
    return EFI_DEVICE_ERROR;
  }
  //
  // Read Register B, and inhibit updates of the RTC
  //
  RegisterB.Data      = RtcRead (RTC_ADDRESS_REGISTER_B);

  RegisterB.Bits.SET  = 1;
  RtcWrite (RTC_ADDRESS_REGISTER_B, RegisterB.Data);

  if (Enable) {
    ConvertEfiTimeToRtcTime (&RtcTime, RegisterB, &Century);

    //
    // Set RTC alarm time
    //
    RtcWrite (RTC_ADDRESS_SECONDS_ALARM, RtcTime.Second);
    RtcWrite (RTC_ADDRESS_MINUTES_ALARM, RtcTime.Minute);
    RtcWrite (RTC_ADDRESS_HOURS_ALARM, RtcTime.Hour);

    RegisterB.Bits.AIE = 1;

  } else {
    RegisterB.Bits.AIE = 0;
  }
  //
  // Allow updates of the RTC registers
  //
  RegisterB.Bits.SET = 0;
  RtcWrite (RTC_ADDRESS_REGISTER_B, RegisterB.Data);

  //
  // Release RTC Lock.
  //
  EfiReleaseLock (&Global->RtcLock);

  return EFI_SUCCESS;
}

UINT8
BcdToDecimal (
  IN  UINT8 BcdValue
  )
/*++

Routine Description:

  Arguments:

  

Returns: 
--*/
// TODO:    BcdValue - add argument and description to function comment
{
  UINTN High;
  UINTN Low;

  High  = BcdValue >> 4;
  Low   = BcdValue - (High << 4);

  return (UINT8) (Low + (High * 10));
}

EFI_STATUS
RtcTestCenturyRegister (
  VOID
  )
/*++

Routine Description:

  Arguments:

  

Returns: 
--*/
// TODO:    EFI_SUCCESS - add return value to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
{
  UINT8 Century;
  UINT8 Temp;

  Century = RtcRead (RTC_ADDRESS_CENTURY);
  //
  //  RtcWrite (RTC_ADDRESS_CENTURY, 0x00);
  //
  Temp = (UINT8) (RtcRead (RTC_ADDRESS_CENTURY) & 0x7f);
  RtcWrite (RTC_ADDRESS_CENTURY, Century);
  if (Temp == 0x19 || Temp == 0x20) {
    return EFI_SUCCESS;
  }

  return EFI_DEVICE_ERROR;
}

VOID
ConvertRtcTimeToEfiTime (
  IN EFI_TIME       *Time,
  IN RTC_REGISTER_B RegisterB
  )
/*++

Routine Description:

  Arguments:

  

Returns: 
--*/
// TODO:    Time - add argument and description to function comment
// TODO:    RegisterB - add argument and description to function comment
{
  BOOLEAN PM;

  if ((Time->Hour) & 0x80) {
    PM = TRUE;
  } else {
    PM = FALSE;
  }

  Time->Hour = (UINT8) (Time->Hour & 0x7f);

  if (RegisterB.Bits.DM == 0) {
    Time->Year    = BcdToDecimal ((UINT8) Time->Year);
    Time->Month   = BcdToDecimal (Time->Month);
    Time->Day     = BcdToDecimal (Time->Day);
    Time->Hour    = BcdToDecimal (Time->Hour);
    Time->Minute  = BcdToDecimal (Time->Minute);
    Time->Second  = BcdToDecimal (Time->Second);
  }
  //
  // If time is in 12 hour format, convert it to 24 hour format
  //
  if (RegisterB.Bits.MIL == 0) {
    if (PM && Time->Hour < 12) {
      Time->Hour = (UINT8) (Time->Hour + 12);
    }

    if (!PM && Time->Hour == 12) {
      Time->Hour = 0;
    }
  }

  Time->Nanosecond  = 0;
  Time->TimeZone    = EFI_UNSPECIFIED_TIMEZONE;
  Time->Daylight    = 0;
}

EFI_STATUS
RtcWaitToUpdate (
  UINTN Timeout
  )
/*++

Routine Description:

  Arguments:
 

Returns: 
--*/
// TODO:    Timeout - add argument and description to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
// TODO:    EFI_DEVICE_ERROR - add return value to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  RTC_REGISTER_A  RegisterA;
  RTC_REGISTER_D  RegisterD;

  //
  // See if the RTC is functioning correctly
  //
  RegisterD.Data = RtcRead (RTC_ADDRESS_REGISTER_D);

  if (RegisterD.Bits.VRT == 0) {
    return EFI_DEVICE_ERROR;
  }
  //
  // Wait for up to 0.1 seconds for the RTC to be ready.
  //
  Timeout         = (Timeout / 10) + 1;
  RegisterA.Data  = RtcRead (RTC_ADDRESS_REGISTER_A);
  while (RegisterA.Bits.UIP == 1 && Timeout > 0) {
    EfiStall (10);
    RegisterA.Data = RtcRead (RTC_ADDRESS_REGISTER_A);
    Timeout--;
  }

  RegisterD.Data = RtcRead (RTC_ADDRESS_REGISTER_D);
  if (Timeout == 0 || RegisterD.Bits.VRT == 0) {
    return EFI_DEVICE_ERROR;
  }

  return EFI_SUCCESS;
}

EFI_STATUS
RtcTimeFieldsValid (
  IN EFI_TIME *Time
  )
/*++

Routine Description:

  Arguments:
 
  Returns: 
--*/
// TODO:    Time - add argument and description to function comment
// TODO:    EFI_INVALID_PARAMETER - add return value to function comment
// TODO:    EFI_SUCCESS - add return value to function comment
{
  if (Time->Year < 1998 ||
      Time->Year > 2099 ||
      Time->Month < 1 ||
      Time->Month > 12 ||
      (!DayValid (Time)) ||
      Time->Hour > 23 ||
      Time->Minute > 59 ||
      Time->Second > 59 ||
      Time->Nanosecond > 999999999 ||
      (!(Time->TimeZone == EFI_UNSPECIFIED_TIMEZONE || (Time->TimeZone >= -1440 && Time->TimeZone <= 1440))) ||
      (Time->Daylight & (~(EFI_TIME_ADJUST_DAYLIGHT | EFI_TIME_IN_DAYLIGHT)))
      ) {
    return EFI_INVALID_PARAMETER;
  }

  return EFI_SUCCESS;
}

BOOLEAN
DayValid (
  IN  EFI_TIME  *Time
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  Time  - TODO: add argument description

Returns:

  TODO: add return values

--*/
{

  INTN  DayOfMonth[12] = { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };

  if (Time->Day < 1 ||
      Time->Day > DayOfMonth[Time->Month - 1] ||
      (Time->Month == 2 && (!IsLeapYear (Time) && Time->Day > 28))
      ) {
    return FALSE;
  }

  return TRUE;
}

BOOLEAN
IsLeapYear (
  IN EFI_TIME   *Time
  )
/*++

Routine Description:

  TODO: Add function description

Arguments:

  Time  - TODO: add argument description

Returns:

  TODO: add return values

--*/
{
  if (Time->Year % 4 == 0) {
    if (Time->Year % 100 == 0) {
      if (Time->Year % 400 == 0) {
        return TRUE;
      } else {
        return FALSE;
      }
    } else {
      return TRUE;
    }
  } else {
    return FALSE;
  }
}

VOID
ConvertEfiTimeToRtcTime (
  IN EFI_TIME       *Time,
  IN RTC_REGISTER_B RegisterB,
  IN UINT8          *Century
  )
/*++

Routine Description:

  Arguments:


Returns: 
--*/
// TODO:    Time - add argument and description to function comment
// TODO:    RegisterB - add argument and description to function comment
// TODO:    Century - add argument and description to function comment
{
  BOOLEAN PM;

  PM = TRUE;
  //
  // Adjust hour field if RTC in in 12 hour mode
  //
  if (RegisterB.Bits.MIL == 0) {
    if (Time->Hour < 12) {
      PM = FALSE;
    }

    if (Time->Hour >= 13) {
      Time->Hour = (UINT8) (Time->Hour - 12);
    } else if (Time->Hour == 0) {
      Time->Hour = 12;
    }
  }
  //
  // Set the Time/Date/Daylight Savings values.
  //
  *Century    = DecimaltoBcd ((UINT8) (Time->Year / 100));

  Time->Year  = (UINT16) (Time->Year % 100);

  if (RegisterB.Bits.DM == 0) {
    Time->Year    = DecimaltoBcd ((UINT8) Time->Year);
    Time->Month   = DecimaltoBcd (Time->Month);
    Time->Day     = DecimaltoBcd (Time->Day);
    Time->Hour    = DecimaltoBcd (Time->Hour);
    Time->Minute  = DecimaltoBcd (Time->Minute);
    Time->Second  = DecimaltoBcd (Time->Second);
  }
  //
  // If we are in 12 hour mode and PM is set, then set bit 7 of the Hour field.
  //
  if (RegisterB.Bits.MIL == 0 && PM) {
    Time->Hour = (UINT8) (Time->Hour | 0x80);
  }
}
 
BOOLEAN 
IsWithinOneDay (
  IN EFI_TIME  *From,
  IN EFI_TIME  *To
  )
/*++

Routine Description:

  Judge whether two days are adjacent.

Arguments:

  From  -   the first day
  To    -   the second day

Returns:

  TRUE  -   The interval of two days are within one day.
  FALSE -   The interval of two days exceed ony day or parameter error.

--*/
{
  UINT8   DayOfMonth[12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
  BOOLEAN Adjacent = FALSE;

  if (From->Year == To->Year) {
    if (From->Month == To->Month) {
      if ((From->Day + 1) == To->Day) {
        Adjacent = TRUE;
      }
    } else if (((From->Month + 1) == To->Month) && (To->Day == 1)) {
      if ((From->Month == 2) && IsLeapYear(From)) {
        if (From->Day == 29) {
          Adjacent = TRUE;
        }
      } else if (From->Day == DayOfMonth[From->Month - 1]) {
        Adjacent = TRUE;
      }
    }
  } else if (((From->Year + 1) == To->Year) &&
             (From->Month == 12) &&
             (From->Day   == 31) &&
             (To->Month   == 1)  &&
             (To->Day     == 1)) {
      Adjacent = TRUE;
  }

  return Adjacent;
}

UINT8
DecimaltoBcd (
  IN  UINT8 DecValue
  )
/*++

Routine Description:

  Arguments:  

Returns: 

--*/
// TODO:    DecValue - add argument and description to function comment
{
  UINTN High;
  UINTN Low;

  High  = DecValue / 10;
  Low   = DecValue - (High * 10);

  return (UINT8) (Low + (High << 4));
}