CorebootPayloadPkg/Library/PlatformHookLib/PlatformHookLib.c

   1 /** @file
   2   Platform Hook Library instance for UART device upon coreboot.
   3
   4   Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
   5   This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include <Base.h>
  16 #include <Uefi/UefiBaseType.h>
  17 #include <Library/PlatformHookLib.h>
  18 #include <Library/CbParseLib.h>
  19 #include <Library/PcdLib.h>
  20
  21 /**
  22   Performs platform specific initialization required for the CPU to access
  23   the hardware associated with a SerialPortLib instance.  This function does
  24   not intiailzie the serial port hardware itself.  Instead, it initializes
  25   hardware devices that are required for the CPU to access the serial port
  26   hardware.  This function may be called more than once.
  27
  28   @retval RETURN_SUCCESS       The platform specific initialization succeeded.
  29   @retval RETURN_DEVICE_ERROR  The platform specific initialization could not be completed.
  30
  31 **/
  32 RETURN_STATUS
  33 EFIAPI
  34 PlatformHookSerialPortInitialize (
  35   VOID
  36   )
  37 {
  38   RETURN_STATUS     Status;
  39   UINT32            SerialRegBase;
  40   UINT32            SerialRegAccessType;
  41
  42   Status = CbParseSerialInfo (&SerialRegBase, &SerialRegAccessType, NULL);
  43   if (RETURN_ERROR (Status)) {
  44     return Status;
  45   }
  46
  47   if (SerialRegAccessType == 2) { //MMIO
  48     PcdSetBoolS (PcdSerialUseMmio, TRUE);
  49   } else { //IO
  50     PcdSetBoolS (PcdSerialUseMmio, FALSE);
  51   }
  52   PcdSet64S (PcdSerialRegisterBase, (UINT64) SerialRegBase);
  53
  54   return RETURN_SUCCESS;
  55 }
  56