Re: [PATCH edk2-platforms 28/41] Silicon/Maxim: DS3232 RTC Library Support

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

On Fri, 21 Dec 2018 at 10:56, Leif Lindholm <leif.lindholm@linaro.org> wrote:
>
> On Wed, Nov 28, 2018 at 08:31:42PM +0530, Meenakshi Aggarwal wrote:
> > From: Wasim Khan <wasim.khan@nxp.com>
> >
> > Add Maxim DS3232 RTC Library support
> >
> > Contributed-under: TianoCore Contribution Agreement 1.1
> > Signed-off-by: Wasim Khan <wasim.khan@nxp.com>
> > Signed-off-by: Meenakshi Aggarwal <meenakshi.aggarwal@nxp.com>
> > Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
> > ---
> >  Silicon/Maxim/Library/Ds3232RtcLib/Ds3232Rtc.h     |  49 +++
> >  Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.c  | 420 +++++++++++++++++++++
> >  .../Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.dec    |  34 ++
> >  .../Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.inf    |  50 +++
> >  4 files changed, 553 insertions(+)
> >  create mode 100644 Silicon/Maxim/Library/Ds3232RtcLib/Ds3232Rtc.h
> >  create mode 100644 Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.c
> >  create mode 100644 Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.dec
> >  create mode 100644 Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.inf
> >
> > diff --git a/Silicon/Maxim/Library/Ds3232RtcLib/Ds3232Rtc.h b/Silicon/Maxim/Library/Ds3232RtcLib/Ds3232Rtc.h
> > new file mode 100644
> > index 0000000..cd1a321
> > --- /dev/null
> > +++ b/Silicon/Maxim/Library/Ds3232RtcLib/Ds3232Rtc.h
> > @@ -0,0 +1,49 @@
> > +/** Ds3232Rtc.h
> > +*
> > +*  Copyright 2017 NXP
> > +*
> > +*  This program and the accompanying materials
> > +*  are licensed and made available under the terms and conditions of the BSD License
> > +*  which accompanies this distribution.  The full text of the license may be found at
> > +*  http://opensource.org/licenses/bsd-license.php
> > +*
> > +*  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
> > +*  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
> > +*
> > +**/
> > +
> > +#ifndef __DS3232RTC_H__
> > +#define __DS3232RTC_H__
> > +
> > +//RTC time register
> > +#define DS3232_SEC_REG_ADDR        0x00
> > +#define DS3232_MIN_REG_ADDR        0x01
> > +#define DS3232_HR_REG_ADDR         0x02
> > +#define DS3232_DAY_REG_ADDR        0x03
> > +#define DS3232_DATE_REG_ADDR       0x04
> > +#define DS3232_MON_REG_ADDR        0x05
> > +#define DS3232_YR_REG_ADDR         0x06
> > +
> > +#define DS3232_SEC_BIT_CH          0x80  // Clock Halt (in Register 0)
> > +
> > +//RTC control register
> > +#define DS3232_CTL_REG_ADDR        0x0e
> > +#define DS3232_STAT_REG_ADDR       0x0f
> > +
> > +#define START_YEAR                 1970
> > +#define END_YEAR                   2070
> > +
> > +//TIME MASKS
> > +#define MASK_SEC                   0x7F
> > +#define MASK_MIN                   0x7F
> > +#define MASK_HOUR                  0x3F
> > +#define MASK_DAY                   0x3F
> > +#define MASK_MONTH                 0x1F
> > +
> > +typedef struct {
> > +  UINTN                           OperationCount;
> > +  EFI_I2C_OPERATION               SetAddressOp;
> > +  EFI_I2C_OPERATION               GetSetDateTimeOp;
> > +} RTC_I2C_REQUEST;
> > +
> > +#endif // __DS3232RTC_H__
> > diff --git a/Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.c b/Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.c
> > new file mode 100644
> > index 0000000..3ab94a8
> > --- /dev/null
> > +++ b/Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.c
> > @@ -0,0 +1,420 @@
> > +/** Ds3232RtcLib.c
> > +*  Implement EFI RealTimeClock via RTC Lib for DS3232 RTC.
> > +*
> > +*  Based on RTC implementation available in
> > +*  EmbeddedPkg/Library/TemplateRealTimeClockLib/RealTimeClockLib.c
> > +*
> > +*  Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
> > +*  Copyright 2017 NXP
> > +*
> > +*  This program and the accompanying materials
> > +*  are licensed and made available under the terms and conditions of the BSD License
> > +*  which accompanies this distribution.  The full text of the license may be found at
> > +*  http://opensource.org/licenses/bsd-license.php
> > +*
> > +*  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
> > +*  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
> > +*
> > +**/
> > +
> > +#include <PiDxe.h>
> > +#include <Base.h>
> > +#include <Library/BaseLib.h>
> > +#include <Library/DebugLib.h>
> > +#include <Library/RealTimeClockLib.h>
> > +#include <Library/UefiBootServicesTableLib.h>
> > +#include <Library/UefiLib.h>
> > +#include <Protocol/I2cMaster.h>
> > +
> > +#include "Ds3232Rtc.h"
> > +
> > +STATIC VOID                       *mDriverEventRegistration;
> > +STATIC EFI_HANDLE                 mI2cMasterHandle;
> > +STATIC EFI_I2C_MASTER_PROTOCOL    *mI2cMaster;
> > +
> > +/**
> > +  Read RTC register.
> > +
> > +  @param  SlaveDeviceAddress   Slave device address offset of RTC to be read.
> > +  @param  RtcRegAddr           Register offset of RTC to be read.
> > +
> > +  @retval                      Register Value read
> > +
> > +**/
> > +STATIC
> > +UINT8
> > +RtcRead (
> > +  IN  UINT8                SlaveDeviceAddress,
> > +  IN  UINT8                RtcRegAddr
> > +  )
> > +{
> > +  RTC_I2C_REQUEST          Req;
> > +  EFI_STATUS               Status;
> > +  UINT8                    Val;
> > +
> > +  Val = 0;
> > +
> > +  Req.OperationCount = 2;
> > +
> > +  Req.SetAddressOp.Flags = 0;
> > +  Req.SetAddressOp.LengthInBytes = sizeof (RtcRegAddr);
> > +  Req.SetAddressOp.Buffer = &RtcRegAddr;
> > +
> > +  Req.GetSetDateTimeOp.Flags = I2C_FLAG_READ;
> > +  Req.GetSetDateTimeOp.LengthInBytes = sizeof (Val);
> > +  Req.GetSetDateTimeOp.Buffer = &Val;
> > +
> > +  Status = mI2cMaster->StartRequest (mI2cMaster, SlaveDeviceAddress,
> > +                                     (VOID *)&Req,
> > +                                     NULL,  NULL);
> > +  if (EFI_ERROR (Status)) {
> > +    DEBUG ((DEBUG_ERROR, "RTC read error at Addr:0x%x\n", RtcRegAddr));
> > +  }
> > +
> > +  return Val;
> > +}
> > +
> > +/**
> > +  Write RTC register.
> > +
> > +  @param  SlaveDeviceAddress   Slave device address offset of RTC to be read.
> > +  @param  RtcRegAddr           Register offset of RTC to write.
> > +  @param  Val                  Value to be written
> > +
> > +**/
> > +STATIC
> > +VOID
> > +RtcWrite (
> > +  IN  UINT8                SlaveDeviceAddress,
> > +  IN  UINT8                RtcRegAddr,
> > +  IN  UINT8                Val
> > +  )
> > +{
> > +  RTC_I2C_REQUEST          Req;
> > +  EFI_STATUS               Status;
> > +
> > +  Req.OperationCount = 2;
> > +
> > +  Req.SetAddressOp.Flags = 0;
> > +  Req.SetAddressOp.LengthInBytes = sizeof (RtcRegAddr);
> > +  Req.SetAddressOp.Buffer = &RtcRegAddr;
> > +
> > +  Req.GetSetDateTimeOp.Flags = 0;
> > +  Req.GetSetDateTimeOp.LengthInBytes = sizeof (Val);
> > +  Req.GetSetDateTimeOp.Buffer = &Val;
> > +
> > +  Status = mI2cMaster->StartRequest (mI2cMaster, SlaveDeviceAddress,
> > +                                     (VOID *)&Req,
> > +                                     NULL,  NULL);
> > +  if (EFI_ERROR (Status)) {
> > +    DEBUG ((DEBUG_ERROR, "RTC write error at Addr:0x%x\n", RtcRegAddr));
> > +  }
> > +}
> > +
> > +/**
> > +  Configure the MUX device connected to I2C.
> > +
> > +  @param  RegValue               Value to write on mux device register address
> > +
> > +**/
> > +VOID
> > +ConfigureMuxDevice (
> > +  IN  UINT8                RegValue
> > +  )
> > +{
> > +  RtcWrite (FixedPcdGet8 (PcdMuxDeviceAddress), FixedPcdGet8 (PcdMuxControlRegOffset), RegValue);
> > +}
> > +
> > +/**
> > +  Returns the current time and date information, and the time-keeping capabilities
> > +  of the hardware platform.
> > +
> > +  @param  Time                  A pointer to storage to receive a snapshot of the current time.
> > +  @param  Capabilities          An optional pointer to a buffer to receive the real time clock
> > +                                device's capabilities.
> > +
> > +  @retval EFI_SUCCESS           The operation completed successfully.
> > +  @retval EFI_INVALID_PARAMETER Time is NULL.
> > +  @retval EFI_DEVICE_ERROR      The time could not be retrieved due to hardware error.
> > +
> > +**/
> > +EFI_STATUS
> > +EFIAPI
> > +LibGetTime (
> > +  OUT  EFI_TIME                 *Time,
> > +  OUT  EFI_TIME_CAPABILITIES    *Capabilities
> > +  )
> > +{
> > +  EFI_STATUS                    Status;
> > +  UINT8                         Second;
> > +  UINT8                         Minute;
> > +  UINT8                         Hour;
> > +  UINT8                         Day;
> > +  UINT8                         Month;
> > +  UINT8                         Year;
> > +
> > +  if (mI2cMaster == NULL) {
> > +    return EFI_DEVICE_ERROR;
> > +  }
> > +
> > +  Status = EFI_SUCCESS;
> > +
> > +  //
> > +  // Check if the I2C device is connected though a MUX device.
> > +  //
> > +  if (FixedPcdGetBool (PcdIsRtcDeviceMuxed)) {
>
> Hmm, if this is the case, then I think we also need a RaiseTPL before
> flipping the mux, and a RestoreTPL after we set it back to default.
> This also needs to be done in any other modules accessing hardware
> behind this mux. TPL_CALLBACK should be sufficient, as long as that's
> what all of the modules use.
>

If this device is behind a mux that is controlled by the OS at
runtime, this RTC is not usable in UEFI.


> > +    // Switch to the channel connected to Ds3232 RTC
> > +    ConfigureMuxDevice (FixedPcdGet8 (PcdMuxRtcChannelValue));
> > +  }
> > +
> > +  Second = RtcRead (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_SEC_REG_ADDR);
> > +  Minute = RtcRead (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_MIN_REG_ADDR);
> > +  Hour = RtcRead (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_HR_REG_ADDR);
> > +  Day = RtcRead (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_DATE_REG_ADDR);
> > +  Month = RtcRead (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_MON_REG_ADDR);
> > +  Year = RtcRead (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_YR_REG_ADDR);
> > +
>
> Please put FixedPcdGet8 (PcdI2cSlaveAddress) into a temporary variable.
>
> > +  if (Second & DS3232_SEC_BIT_CH) {
> > +    DEBUG ((DEBUG_ERROR, "### Warning: RTC oscillator has stopped\n"));
> > +    /* clear the CH flag */
> > +    RtcWrite (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_SEC_REG_ADDR,
> > +              RtcRead (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_SEC_REG_ADDR) & ~DS3232_SEC_BIT_CH);
>
> That should also clean up this line somewhat.
>
> > +    Status = EFI_DEVICE_ERROR;
> > +    goto EXIT;
> > +  }
> > +
> > +  Time->Second  = BcdToDecimal8 (Second & MASK_SEC);
> > +  Time->Minute  = BcdToDecimal8 (Minute & MASK_MIN);
> > +  Time->Hour = BcdToDecimal8 (Hour & MASK_HOUR);
> > +  Time->Day = BcdToDecimal8 (Day & MASK_DAY);
> > +  Time->Month  = BcdToDecimal8 (Month & MASK_MONTH);
> > +
> > +  //
> > +  // RTC can save year 1970 to 2069
> > +  // On writing Year, save year % 100
> > +  // On Reading reversing the operation e.g. 2012
> > +  // write = 12 (2012 % 100)
> > +  // read = 2012 (12 + 2000)
> > +  //
> > +  Time->Year = BcdToDecimal8 (Year) +
> > +               (BcdToDecimal8 (Year) >= 70 ? START_YEAR - 70 : END_YEAR -70);
>
> Please break the adjustment out into its own calculation and a
> temmporary variable.
>
> > +
> > +EXIT:
> > +  if (FixedPcdGetBool (PcdIsRtcDeviceMuxed)) {
> > +    // Switch to the default channel
> > +    ConfigureMuxDevice (FixedPcdGet8 (PcdMuxDefaultChannelValue));
> > +  }
> > +
> > +  return Status;
> > +}
> > +
> > +/**
> > +  Sets the current local time and date information.
> > +
> > +  @param  Time                  A pointer to the current time.
> > +
> > +  @retval EFI_SUCCESS           The operation completed successfully.
> > +  @retval EFI_INVALID_PARAMETER A time field is out of range.
> > +
> > +**/
> > +EFI_STATUS
> > +EFIAPI
> > +LibSetTime (
> > +  IN  EFI_TIME                *Time
> > +  )
> > +{
> > +  if (mI2cMaster == NULL) {
> > +    return EFI_DEVICE_ERROR;
> > +  }
> > +
> > +  if (Time->Year < START_YEAR || Time->Year >= END_YEAR){
> > +    DEBUG ((DEBUG_ERROR, "WARNING: Year should be between 1970 and 2069!\n"));
> > +    return EFI_INVALID_PARAMETER;
> > +  }
> > +
> > +  //
> > +  // Check if the I2C device is connected though a MUX device.
> > +  //
> > +  if (FixedPcdGetBool (PcdIsRtcDeviceMuxed)) {
> > +    // Switch to the channel connected to Ds3232 RTC
> > +    ConfigureMuxDevice (FixedPcdGet8 (PcdMuxRtcChannelValue));
> > +  }
> > +
> > +  RtcWrite (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_YR_REG_ADDR, DecimalToBcd8 (Time->Year % 100));
> > +  RtcWrite (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_MON_REG_ADDR, DecimalToBcd8 (Time->Month));
> > +  RtcWrite (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_DATE_REG_ADDR, DecimalToBcd8 (Time->Day));
> > +  RtcWrite (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_HR_REG_ADDR, DecimalToBcd8 (Time->Hour));
> > +  RtcWrite (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_MIN_REG_ADDR, DecimalToBcd8 (Time->Minute));
> > +  RtcWrite (FixedPcdGet8 (PcdI2cSlaveAddress), DS3232_SEC_REG_ADDR, DecimalToBcd8 (Time->Second));
>
> FixedPcdGet8 (PcdI2cSlaveAddress) in a temporary variable, please.
>
> /
>     Leif
>
> > +
> > +  if (FixedPcdGetBool (PcdIsRtcDeviceMuxed)) {
> > +    // Switch to the default channel
> > +    ConfigureMuxDevice (FixedPcdGet8 (PcdMuxDefaultChannelValue));
> > +  }
> > +
> > +  return EFI_SUCCESS;
> > +}
> > +
> > +/**
> > +  Returns the current wakeup alarm clock setting.
> > +
> > +  @param  Enabled               Indicates if the alarm is currently enabled or disabled.
> > +  @param  Pending               Indicates if the alarm signal is pending and requires acknowledgement.
> > +  @param  Time                  The current alarm setting.
> > +
> > +  @retval EFI_SUCCESS           The alarm settings were returned.
> > +  @retval EFI_INVALID_PARAMETER Any parameter is NULL.
> > +  @retval EFI_DEVICE_ERROR      The wakeup time could not be retrieved due to a hardware error.
> > +
> > +**/
> > +EFI_STATUS
> > +EFIAPI
> > +LibGetWakeupTime (
> > +  OUT  BOOLEAN                  *Enabled,
> > +  OUT  BOOLEAN                  *Pending,
> > +  OUT  EFI_TIME                 *Time
> > +  )
> > +{
> > +  // Currently not supporting this feature.
> > +  return EFI_UNSUPPORTED;
> > +}
> > +
> > +/**
> > +  Sets the system wakeup alarm clock time.
> > +
> > +  @param  Enabled               Enable or disable the wakeup alarm.
> > +  @param  Time                  If Enable is TRUE, the time to set the wakeup alarm for.
> > +
> > +  @retval EFI_SUCCESS           If Enable is TRUE, then the wakeup alarm was enabled. If
> > +                                Enable is FALSE, then the wakeup alarm was disabled.
> > +  @retval EFI_INVALID_PARAMETER A time field is out of range.
> > +  @retval EFI_DEVICE_ERROR      The wakeup time could not be set due to a hardware error.
> > +  @retval EFI_UNSUPPORTED       A wakeup timer is not supported on this platform.
> > +
> > +**/
> > +EFI_STATUS
> > +EFIAPI
> > +LibSetWakeupTime (
> > +  IN BOOLEAN                    Enabled,
> > +  OUT EFI_TIME                  *Time
> > +  )
> > +{
> > +  // Currently not supporting this feature.
> > +  return EFI_UNSUPPORTED;
> > +}
> > +
> > +STATIC
> > +VOID
> > +I2cDriverRegistrationEvent (
> > +  IN  EFI_EVENT                 Event,
> > +  IN  VOID                      *Context
> > +  )
> > +{
> > +  EFI_STATUS                    Status;
> > +  EFI_I2C_MASTER_PROTOCOL       *I2cMaster;
> > +  UINTN                         BusFrequency;
> > +  EFI_HANDLE                    Handle;
> > +  UINTN                         BufferSize;
> > +
> > +  //
> > +  // Try to connect the newly registered driver to our handle.
> > +  //
> > +  do {
> > +    BufferSize = sizeof (EFI_HANDLE);
> > +    Status = gBS->LocateHandle (ByRegisterNotify,
> > +                                &gEfiI2cMasterProtocolGuid,
> > +                                mDriverEventRegistration,
> > +                                &BufferSize,
> > +                                &Handle);
> > +    if (EFI_ERROR (Status)) {
> > +      if (Status != EFI_NOT_FOUND) {
> > +        DEBUG ((DEBUG_WARN, "%a: gBS->LocateHandle () returned %r\n",
> > +          __FUNCTION__, Status));
> > +      }
> > +      break;
> > +    }
> > +
> > +    if (Handle != mI2cMasterHandle) {
> > +      continue;
> > +    }
> > +
> > +    DEBUG ((DEBUG_INFO, "%a: found I2C master!\n", __FUNCTION__));
> > +
> > +    gBS->CloseEvent (Event);
> > +
> > +    Status = gBS->OpenProtocol (mI2cMasterHandle, &gEfiI2cMasterProtocolGuid,
> > +                    (VOID **)&I2cMaster, gImageHandle, NULL,
> > +                    EFI_OPEN_PROTOCOL_EXCLUSIVE);
> > +    ASSERT_EFI_ERROR (Status);
> > +
> > +    Status = I2cMaster->Reset (I2cMaster);
> > +    if (EFI_ERROR (Status)) {
> > +      DEBUG ((DEBUG_ERROR, "%a: I2CMaster->Reset () failed - %r\n",
> > +        __FUNCTION__, Status));
> > +      break;
> > +    }
> > +
> > +    BusFrequency = FixedPcdGet16 (PcdI2cBusFrequency);
> > +    Status = I2cMaster->SetBusFrequency (I2cMaster, &BusFrequency);
> > +    if (EFI_ERROR (Status)) {
> > +      DEBUG ((DEBUG_ERROR, "%a: I2CMaster->SetBusFrequency () failed - %r\n",
> > +        __FUNCTION__, Status));
> > +      break;
> > +    }
> > +
> > +    mI2cMaster = I2cMaster;
> > +    break;
> > +  } while (TRUE);
> > +
> > +  return;
> > +
> > +}
> > +
> > +/**
> > +  This is the declaration of an EFI image entry point. This can be the entry point to an application
> > +  written to this specification, an EFI boot service driver.
> > +
> > +  @param  ImageHandle           Handle that identifies the loaded image.
> > +  @param  SystemTable           System Table for this image.
> > +
> > +  @retval EFI_SUCCESS           The operation completed successfully.
> > +
> > +**/
> > +EFI_STATUS
> > +EFIAPI
> > +LibRtcInitialize (
> > +  IN EFI_HANDLE                 ImageHandle,
> > +  IN EFI_SYSTEM_TABLE           *SystemTable
> > +  )
> > +{
> > +  EFI_STATUS          Status;
> > +  UINTN               BufferSize;
> > +
> > +  //
> > +  // Find the handle that marks the controller
> > +  // that will provide the I2C master protocol.
> > +  //
> > +  BufferSize = sizeof (EFI_HANDLE);
> > +  Status = gBS->LocateHandle (
> > +                  ByProtocol,
> > +                  &gDs3232RealTimeClockLibI2cMasterProtocolGuid,
> > +                  NULL,
> > +                  &BufferSize,
> > +                  &mI2cMasterHandle
> > +                  );
> > +  ASSERT_EFI_ERROR (Status);
> > +
> > +  //
> > +  // Register a protocol registration notification callback on the driver
> > +  // binding protocol so we can attempt to connect our I2C master to it
> > +  // as soon as it appears.
> > +  //
> > +  EfiCreateProtocolNotifyEvent (
> > +    &gEfiI2cMasterProtocolGuid,
> > +    TPL_CALLBACK,
> > +    I2cDriverRegistrationEvent,
> > +    NULL,
> > +    &mDriverEventRegistration);
> > +
> > +  return EFI_SUCCESS;
> > +}
> > diff --git a/Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.dec b/Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.dec
> > new file mode 100644
> > index 0000000..a0033a2
> > --- /dev/null
> > +++ b/Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.dec
> > @@ -0,0 +1,34 @@
> > +#/** @file
> > +#
> > +# Copyright 2017 NXP
> > +#
> > +# This program and the accompanying materials
> > +# are licensed and made available under the terms and conditions of the BSD License
> > +# which accompanies this distribution.  The full text of the license may be found at
> > +# http://opensource.org/licenses/bsd-license.php
> > +#
> > +# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
> > +# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
> > +#
> > +#**/
> > +
> > +[Defines]
> > +  DEC_SPECIFICATION              = 0x0001001A
> > +  PACKAGE_NAME                   = Ds3232RtcLib
> > +  PACKAGE_GUID                   = 0b4192f7-e404-4019-b2e5-1e6004da3313
> > +  PACKAGE_VERSION                = 0.1
> > +
> > +[Guids]
> > +  gDs3232RtcLibTokenSpaceGuid = { 0x7960fc51, 0x0832, 0x4f0b, { 0xb4, 0x22, 0x53, 0x87, 0x03, 0xaa, 0x85, 0xda }}
> > +
> > +[Protocols]
> > +  gDs3232RealTimeClockLibI2cMasterProtocolGuid = { 0xa17eb2ee, 0xcadc, 0x40f1, { 0x8a, 0x45, 0x4d, 0x5a, 0xf3, 0xd6, 0xce, 0x53 }}
> > +
> > +[PcdsFixedAtBuild]
> > +  gDs3232RtcLibTokenSpaceGuid.PcdI2cSlaveAddress|0|UINT8|0x00000001
> > +  gDs3232RtcLibTokenSpaceGuid.PcdI2cBusFrequency|0|UINT32|0x00000002
> > +  gDs3232RtcLibTokenSpaceGuid.PcdIsRtcDeviceMuxed|FALSE|BOOLEAN|0x00000003
> > +  gDs3232RtcLibTokenSpaceGuid.PcdMuxDeviceAddress|0|UINT8|0x00000004
> > +  gDs3232RtcLibTokenSpaceGuid.PcdMuxControlRegOffset|0|UINT8|0x00000005
> > +  gDs3232RtcLibTokenSpaceGuid.PcdMuxRtcChannelValue|0|UINT8|0x00000006
> > +  gDs3232RtcLibTokenSpaceGuid.PcdMuxDefaultChannelValue|0|UINT8|0x00000007
> > diff --git a/Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.inf b/Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.inf
> > new file mode 100644
> > index 0000000..95664c1
> > --- /dev/null
> > +++ b/Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.inf
> > @@ -0,0 +1,50 @@
> > +#  @Ds3232RtcLib.inf
> > +#
> > +#  Copyright (c) 2016, Freescale Semiconductor, Inc. All rights reserved.
> > +#  Copyright 2017 NXP
> > +#
> > +#  This program and the accompanying materials
> > +#  are licensed and made available under the terms and conditions of the BSD License
> > +#  which accompanies this distribution. The full text of the license may be found at
> > +#  http://opensource.org/licenses/bsd-license.php
> > +#  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
> > +#  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
> > +#
> > +#
> > +
> > +[Defines]
> > +  INF_VERSION                    = 0x0001001A
> > +  BASE_NAME                      = Ds3232RtcLib
> > +  FILE_GUID                      = 97f1f2c2-51e1-47ad-9660-70b33da1fe71
> > +  MODULE_TYPE                    = BASE
> > +  VERSION_STRING                 = 1.0
> > +  LIBRARY_CLASS                  = RealTimeClockLib
> > +
> > +[Sources.common]
> > +  Ds3232RtcLib.c
> > +
> > +[Packages]
> > +  EmbeddedPkg/EmbeddedPkg.dec
> > +  MdePkg/MdePkg.dec
> > +  Silicon/Maxim/Library/Ds3232RtcLib/Ds3232RtcLib.dec
> > +
> > +[LibraryClasses]
> > +  DebugLib
> > +  UefiBootServicesTableLib
> > +  UefiLib
> > +
> > +[Protocols]
> > +  gEfiI2cMasterProtocolGuid                          ## CONSUMES
> > +  gDs3232RealTimeClockLibI2cMasterProtocolGuid       ## CONSUMES
> > +
> > +[FixedPcd]
> > +  gDs3232RtcLibTokenSpaceGuid.PcdI2cSlaveAddress
> > +  gDs3232RtcLibTokenSpaceGuid.PcdI2cBusFrequency
> > +  gDs3232RtcLibTokenSpaceGuid.PcdIsRtcDeviceMuxed
> > +  gDs3232RtcLibTokenSpaceGuid.PcdMuxDeviceAddress
> > +  gDs3232RtcLibTokenSpaceGuid.PcdMuxControlRegOffset
> > +  gDs3232RtcLibTokenSpaceGuid.PcdMuxRtcChannelValue
> > +  gDs3232RtcLibTokenSpaceGuid.PcdMuxDefaultChannelValue
> > +
> > +[Depex]
> > +  gDs3232RealTimeClockLibI2cMasterProtocolGuid
> > --
> > 1.9.1
> >