Vlv2TbltDevicePkg/FspSupport/Library/SecFspPlatformSecLibVlv2/SecPlatformInformation.c

   1 /** @file
   2
   3   Copyright (c) 2014, Intel Corporation. All rights reserved.<BR>
   4   This program and the accompanying materials are licensed and
   5   made available under the terms and conditions of the BSD License
   6   which accompanies this distribution.  The full text of the license may be found at
   7   http://opensource.org/licenses/bsd-license.php.
   8
   9   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11
  12 **/
  13
  14 #include <PiPei.h>
  15
  16 #include <Ppi/SecPlatformInformation.h>
  17 #include <Ppi/TopOfTemporaryRam.h>
  18
  19 #include <Library/BaseMemoryLib.h>
  20 #include <Library/DebugLib.h>
  21
  22 /**
  23   This interface conveys state information out of the Security (SEC) phase into PEI.
  24
  25   @param  PeiServices               Pointer to the PEI Services Table.
  26   @param  StructureSize             Pointer to the variable describing size of the input buffer.
  27   @param  PlatformInformationRecord Pointer to the EFI_SEC_PLATFORM_INFORMATION_RECORD.
  28
  29   @retval EFI_SUCCESS           The data was successfully returned.
  30   @retval EFI_BUFFER_TOO_SMALL  The buffer was too small.
  31
  32 **/
  33 EFI_STATUS
  34 EFIAPI
  35 SecPlatformInformation (
  36   IN CONST EFI_PEI_SERVICES                     **PeiServices,
  37   IN OUT   UINT64                               *StructureSize,
  38      OUT   EFI_SEC_PLATFORM_INFORMATION_RECORD  *PlatformInformationRecord
  39   )
  40 {
  41   UINT32      *Bist;
  42   UINT32      Size;
  43   UINT32      Count;
  44   UINT32      TopOfTemporaryRam;
  45   VOID        *TopOfTemporaryRamPpi;
  46   EFI_STATUS  Status;
  47
  48   DEBUG ((DEBUG_INFO, "SecPlatformInformation\n"));
  49
  50   Status = (*PeiServices)->LocatePpi (
  51                              PeiServices,
  52                              &gTopOfTemporaryRamPpiGuid,
  53                              0,
  54                              NULL,
  55                              (VOID **) &TopOfTemporaryRamPpi
  56                              );
  57   if (EFI_ERROR (Status)) {
  58     return EFI_NOT_FOUND;
  59   }
  60
  61   //
  62   // The entries of BIST information, together with the number of them,
  63   // reside in the bottom of stack, left untouched by normal stack operation.
  64   // This routine copies the BIST information to the buffer pointed by
  65   // PlatformInformationRecord for output.
  66   //
  67   TopOfTemporaryRam = (UINT32)(UINTN)TopOfTemporaryRamPpi - sizeof (UINT32);
  68   TopOfTemporaryRam -= sizeof(UINT32) * 2;
  69   Count             = *((UINT32 *)(UINTN) (TopOfTemporaryRam - sizeof (UINT32)));
  70   Size              = Count * sizeof (IA32_HANDOFF_STATUS);
  71
  72   if ((*StructureSize) < (UINT64) Size) {
  73     *StructureSize = Size;
  74     return EFI_BUFFER_TOO_SMALL;
  75   }
  76
  77   *StructureSize  = Size;
  78   Bist            = (UINT32 *) (TopOfTemporaryRam - sizeof (UINT32) - Size);
  79
  80   CopyMem (PlatformInformationRecord, Bist, Size);
  81
  82   return EFI_SUCCESS;
  83 }