alder_lake_bios/Intel/AlderLake/ClientOneSiliconPkg/Library/BaseSystemTimeLib/BaseSystemTimeLib.c

/** @file
  Source file for BaseSystemTimeLib.

@copyright
  INTEL CONFIDENTIAL
  Copyright 2020 Intel Corporation.

  The source code contained or described herein and all documents related to the
  source code ("Material") are owned by Intel Corporation or its suppliers or
  licensors. Title to the Material remains with Intel Corporation or its suppliers
  and licensors. The Material may contain trade secrets and proprietary and
  confidential information of Intel Corporation and its suppliers and licensors,
  and is protected by worldwide copyright and trade secret laws and treaty
  provisions. No part of the Material may be used, copied, reproduced, modified,
  published, uploaded, posted, transmitted, distributed, or disclosed in any way
  without Intel's prior express written permission.

  No license under any patent, copyright, trade secret or other intellectual
  property right is granted to or conferred upon you by disclosure or delivery
  of the Materials, either expressly, by implication, inducement, estoppel or
  otherwise. Any license under such intellectual property rights must be
  express and approved by Intel in writing.

  Unless otherwise agreed by Intel in writing, you may not remove or alter
  this notice or any other notice embedded in Materials by Intel or
  Intel's suppliers or licensors in any way.

  This file contains an 'Intel Peripheral Driver' and is uniquely identified as
  "Intel Reference Module" and is licensed for Intel CPUs and chipsets under
  the terms of your license agreement with Intel or your vendor. This file may
  be modified by the user, subject to additional terms of the license agreement.

@par Specification Reference:
**/

#include <Library/SystemTimeLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/TimerLib.h>
#include <Library/IoLib.h>

/**
  This funtion will output the system time in (YYYY-MM-DD-HH-MM-SS) format

  @param[out] SYSTEM_TIME      typedef struct for system time
**/
VOID
GetSystemTime (
  OUT SYSTEM_TIME *const SystemTime
  )
{
  UINT32           Timeout;

  //
  // Wait until RTC "update in progress" bit goes low.
  //
  Timeout = 0x0FFFFF;
  do {
    IoWrite8 (RTC_INDEX_REGISTER, CMOS_REGA);
    if ((IoRead8 (RTC_TARGET_REGISTER) & RTC_UPDATE_IN_PROGRESS) != RTC_UPDATE_IN_PROGRESS) {
      break;
    }
  } while (--Timeout > 0);

  if (0 == Timeout) {
    IoWrite8 (RTC_INDEX_REGISTER, CMOS_REGB);
    IoWrite8 (RTC_TARGET_REGISTER, RTC_HOLD | RTC_MODE_24HOUR);

    IoWrite8 (RTC_INDEX_REGISTER, CMOS_REGA);
    IoWrite8 (RTC_TARGET_REGISTER, RTC_CLOCK_DIVIDER | RTC_RATE_SELECT);

    IoWrite8 (RTC_INDEX_REGISTER, CMOS_REGC);
    IoRead8 (RTC_TARGET_REGISTER);

    IoWrite8 (RTC_INDEX_REGISTER, CMOS_REGD);
    IoRead8 (RTC_TARGET_REGISTER);

    IoWrite8 (RTC_INDEX_REGISTER, CMOS_REGB);
    IoWrite8 (RTC_TARGET_REGISTER, RTC_MODE_24HOUR);
  }
  //
  // Read seconds
  //
  IoWrite8 (RTC_INDEX_REGISTER, RTC_SECONDS);
  SystemTime->Data.Seconds = IoRead8(RTC_TARGET_REGISTER);

  //
  // Read minutes
  //
  IoWrite8 (RTC_INDEX_REGISTER, RTC_MINUTES);
  SystemTime->Data.Minutes = IoRead8(RTC_TARGET_REGISTER);

  //
  // Read hours
  //
  IoWrite8 (RTC_INDEX_REGISTER, RTC_HOURS);
  SystemTime->Data.Hours = IoRead8(RTC_TARGET_REGISTER);

  //
  // Read day of month
  //
  IoWrite8 (RTC_INDEX_REGISTER, RTC_DAY_OF_MONTH);
  SystemTime->Data.DayOfMonth = IoRead8(RTC_TARGET_REGISTER);

  //
  // Read month
  //
  IoWrite8 (RTC_INDEX_REGISTER, RTC_MONTH);
  SystemTime->Data.Month = IoRead8(RTC_TARGET_REGISTER);

  //
  // Read year and add current century.
  //
  IoWrite8 (RTC_INDEX_REGISTER, RTC_YEAR);
  SystemTime->Data.Year = IoRead8(RTC_TARGET_REGISTER);

  SystemTime->Data.Seconds = BCD2BINARY(SystemTime->Data.Seconds);
  SystemTime->Data.Minutes = BCD2BINARY(SystemTime->Data.Minutes);
  SystemTime->Data.Hours = BCD2BINARY(SystemTime->Data.Hours);
  SystemTime->Data.DayOfMonth = BCD2BINARY(SystemTime->Data.DayOfMonth);
  SystemTime->Data.Month = BCD2BINARY(SystemTime->Data.Month);
  SystemTime->Data.Year = BCD2BINARY(SystemTime->Data.Year) + CENTURY_OFFSET;

}

/**
  This funtion returns Unix Time: The number of milliseconds since 1 January 1970.

  @param[in] SYSTEM_TIME      typedef struct for system time

  @retval  UINT64             Total time in milli seconds
**/
UINT64
ConvertSystemTimeToUnixFormat (
  IN SYSTEM_TIME *SystemTime
)
{
  UINT64                 NoOfMilliSec;
  UINT8                  LeapYearCount;
  UINT16                 TotalYears;
  UINT8                  Month;
  UINT16                 AddDays;
  UINT16                 Year;

  LeapYearCount = 0;
  NoOfMilliSec = 0;
  TotalYears = 0;
  Month = 0;
  AddDays = 0;

  //
  // Calculate Total time in milli seconds till previous year.
  //
  if (SystemTime->Data.Year > 1970) {
    TotalYears = SystemTime->Data.Year - 1970 - 1;
  }
  // check for total leap years
  for (Year = 1970; Year < SystemTime->Data.Year; Year++) {
    if (Year % 4 == 0) {
      if (Year % 100 == 0) {
        if (Year % 400 == 0) {
          LeapYearCount++;
        }
      } else {
        LeapYearCount++;
      }
    }
  }
  // time in milli seconds till previous year
  NoOfMilliSec = (UINT64)(TotalYears * (365 + LeapYearCount) * 24 * 60 * 60 * 1000);

  //
  // Calculate time in milli seconds for current year.
  //
  while (Month <= SystemTime->Data.Month) {
    if (Month != SystemTime->Data.Month) {
      if (Month == 1 || Month == 3 || Month == 5 || Month == 7 || Month == 8 || Month == 10 || Month == 12) {
        AddDays += 31;
      } else if (Month == 4 || Month == 6 || Month == 9 || Month == 11) {
        AddDays += 30;
      } else if (Month == 2) {
        if (SystemTime->Data.Year % 4 == 0) {
          if (SystemTime->Data.Year % 100 == 0) {
            if (SystemTime->Data.Year % 400 == 0) {
              AddDays += 29;
            } else {
              AddDays += 28;
            }
          } else {
            AddDays += 29;
          }
        } else {
          AddDays += 28;
        }
      }
    } else {
      AddDays += (SystemTime->Data.DayOfMonth - 1);
      NoOfMilliSec += (AddDays * SystemTime->Data.Hours * SystemTime->Data.Minutes * SystemTime->Data.Seconds * 1000);
      break;
    }
    Month++;
  }

  return (UINT64)(NoOfMilliSec);

}