IntelFsp2WrapperPkg/Library/SecFspWrapperPlatformSecLibSample/SecPlatformInformation.c

   1 /** @file
   2   Sample to provide SecPlatformInformation function.
   3
   4   Copyright (c) 2014, 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 <PiPei.h>
  16
  17 #include <Ppi/SecPlatformInformation.h>
  18 #include <Ppi/TopOfTemporaryRam.h>
  19
  20 #include <Library/BaseMemoryLib.h>
  21 #include <Library/DebugLib.h>
  22
  23 /**
  24   This interface conveys state information out of the Security (SEC) phase into PEI.
  25
  26   @param[in]     PeiServices               Pointer to the PEI Services Table.
  27   @param[in,out] StructureSize             Pointer to the variable describing size of the input buffer.
  28   @param[out]    PlatformInformationRecord Pointer to the EFI_SEC_PLATFORM_INFORMATION_RECORD.
  29
  30   @retval EFI_SUCCESS           The data was successfully returned.
  31   @retval EFI_BUFFER_TOO_SMALL  The buffer was too small.
  32
  33 **/
  34 EFI_STATUS
  35 EFIAPI
  36 SecPlatformInformation (
  37   IN CONST EFI_PEI_SERVICES                     **PeiServices,
  38   IN OUT   UINT64                               *StructureSize,
  39      OUT   EFI_SEC_PLATFORM_INFORMATION_RECORD  *PlatformInformationRecord
  40   )
  41 {
  42   UINT32      *Bist;
  43   UINT32      Size;
  44   UINT32      Count;
  45   UINT32      TopOfTemporaryRam;
  46   VOID        *TopOfTemporaryRamPpi;
  47   EFI_STATUS  Status;
  48
  49   DEBUG ((DEBUG_INFO, "SecPlatformInformation\n"));
  50
  51   Status = (*PeiServices)->LocatePpi (
  52                              PeiServices,
  53                              &gTopOfTemporaryRamPpiGuid,
  54                              0,
  55                              NULL,
  56                              (VOID **) &TopOfTemporaryRamPpi
  57                              );
  58   if (EFI_ERROR (Status)) {
  59     return EFI_NOT_FOUND;
  60   }
  61
  62   //
  63   // The entries of BIST information, together with the number of them,
  64   // reside in the bottom of stack, left untouched by normal stack operation.
  65   // This routine copies the BIST information to the buffer pointed by
  66   // PlatformInformationRecord for output.
  67   //
  68   TopOfTemporaryRam = (UINT32)(UINTN)TopOfTemporaryRamPpi - sizeof (UINT32);
  69   TopOfTemporaryRam -= sizeof(UINT32) * 2;
  70   Count             = *((UINT32 *)(UINTN) (TopOfTemporaryRam - sizeof (UINT32)));
  71   Size              = Count * sizeof (IA32_HANDOFF_STATUS);
  72
  73   if ((*StructureSize) < (UINT64) Size) {
  74     *StructureSize = Size;
  75     return EFI_BUFFER_TOO_SMALL;
  76   }
  77
  78   *StructureSize  = Size;
  79   Bist            = (UINT32 *) (TopOfTemporaryRam - sizeof (UINT32) - Size);
  80
  81   CopyMem (PlatformInformationRecord, Bist, Size);
  82
  83   return EFI_SUCCESS;
  84 }