OvmfPkg/PlatformPei/MemTypeInfo.c

   1 /** @file
   2   Produce a default memory type information HOB unless we can determine, from
   3   the existence of the "MemoryTypeInformation" variable, that the DXE IPL PEIM
   4   will produce the HOB.
   5
   6   Copyright (C) 2017-2020, Red Hat, Inc.
   7
   8   SPDX-License-Identifier: BSD-2-Clause-Patent
   9 **/
  10
  11 #include <Guid/MemoryTypeInformation.h>
  12 #include <Library/BaseLib.h>
  13 #include <Library/DebugLib.h>
  14 #include <Library/HobLib.h>
  15 #include <Library/PcdLib.h>
  16 #include <Library/PeiServicesLib.h>
  17 #include <Ppi/ReadOnlyVariable2.h>
  18 #include <Uefi/UefiMultiPhase.h>
  19
  20 #include "Platform.h"
  21
  22 //
  23 // The NumberOfPages values below are ad-hoc. They are updated sporadically at
  24 // best (please refer to git-blame for past updates). The values capture a set
  25 // of BIN hints that made sense at a particular time, for some (now likely
  26 // unknown) workloads / boot paths.
  27 //
  28 STATIC EFI_MEMORY_TYPE_INFORMATION mDefaultMemoryTypeInformation[] = {
  29   { EfiACPIMemoryNVS,       0x004 },
  30   { EfiACPIReclaimMemory,   0x008 },
  31   { EfiReservedMemoryType,  0x004 },
  32   { EfiRuntimeServicesData, 0x024 },
  33   { EfiRuntimeServicesCode, 0x030 },
  34   { EfiBootServicesCode,    0x180 },
  35   { EfiBootServicesData,    0xF00 },
  36   { EfiMaxMemoryType,       0x000 }
  37 };
  38
  39 STATIC
  40 VOID
  41 BuildMemTypeInfoHob (
  42   VOID
  43   )
  44 {
  45   BuildGuidDataHob (
  46     &gEfiMemoryTypeInformationGuid,
  47     mDefaultMemoryTypeInformation,
  48     sizeof mDefaultMemoryTypeInformation
  49     );
  50   DEBUG ((DEBUG_INFO, "%a: default memory type information HOB built\n",
  51     __FUNCTION__));
  52 }
  53
  54 /**
  55   Notification function called when EFI_PEI_READ_ONLY_VARIABLE2_PPI becomes
  56   available.
  57
  58   @param[in] PeiServices      Indirect reference to the PEI Services Table.
  59   @param[in] NotifyDescriptor Address of the notification descriptor data
  60                               structure.
  61   @param[in] Ppi              Address of the PPI that was installed.
  62
  63   @return  Status of the notification. The status code returned from this
  64            function is ignored.
  65 **/
  66 STATIC
  67 EFI_STATUS
  68 EFIAPI
  69 OnReadOnlyVariable2Available (
  70   IN EFI_PEI_SERVICES           **PeiServices,
  71   IN EFI_PEI_NOTIFY_DESCRIPTOR  *NotifyDescriptor,
  72   IN VOID                       *Ppi
  73   )
  74 {
  75   EFI_PEI_READ_ONLY_VARIABLE2_PPI *ReadOnlyVariable2;
  76   UINTN                           DataSize;
  77   EFI_STATUS                      Status;
  78
  79   DEBUG ((DEBUG_VERBOSE, "%a\n", __FUNCTION__));
  80
  81   //
  82   // Check if the "MemoryTypeInformation" variable exists, in the
  83   // gEfiMemoryTypeInformationGuid namespace.
  84   //
  85   ReadOnlyVariable2 = Ppi;
  86   DataSize = 0;
  87   Status = ReadOnlyVariable2->GetVariable (
  88                                 ReadOnlyVariable2,
  89                                 EFI_MEMORY_TYPE_INFORMATION_VARIABLE_NAME,
  90                                 &gEfiMemoryTypeInformationGuid,
  91                                 NULL,
  92                                 &DataSize,
  93                                 NULL
  94                                 );
  95   switch (Status) {
  96   case EFI_BUFFER_TOO_SMALL:
  97     //
  98     // The variable exists; the DXE IPL PEIM will build the HOB from it.
  99     //
 100     break;
 101   case EFI_NOT_FOUND:
 102     //
 103     // The variable does not exist; install the default memory type information
 104     // HOB.
 105     //
 106     BuildMemTypeInfoHob ();
 107     break;
 108   default:
 109     DEBUG ((DEBUG_ERROR, "%a: unexpected: GetVariable(): %r\n", __FUNCTION__,
 110       Status));
 111     ASSERT (FALSE);
 112     CpuDeadLoop ();
 113     break;
 114   }
 115
 116   return EFI_SUCCESS;
 117 }
 118
 119 //
 120 // Notification object for registering the callback, for when
 121 // EFI_PEI_READ_ONLY_VARIABLE2_PPI becomes available.
 122 //
 123 STATIC CONST EFI_PEI_NOTIFY_DESCRIPTOR mReadOnlyVariable2Notify = {
 124   (EFI_PEI_PPI_DESCRIPTOR_NOTIFY_DISPATCH |
 125    EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST),  // Flags
 126   &gEfiPeiReadOnlyVariable2PpiGuid,         // Guid
 127   OnReadOnlyVariable2Available              // Notify
 128 };
 129
 130 VOID
 131 MemTypeInfoInitialization (
 132   VOID
 133   )
 134 {
 135   EFI_STATUS Status;
 136
 137   if (!FeaturePcdGet (PcdSmmSmramRequire)) {
 138     //
 139     // EFI_PEI_READ_ONLY_VARIABLE2_PPI will never be available; install
 140     // the default memory type information HOB right away.
 141     //
 142     BuildMemTypeInfoHob ();
 143     return;
 144   }
 145
 146   Status = PeiServicesNotifyPpi (&mReadOnlyVariable2Notify);
 147   if (EFI_ERROR (Status)) {
 148     DEBUG ((DEBUG_ERROR, "%a: failed to set up R/O Variable 2 callback: %r\n",
 149       __FUNCTION__, Status));
 150     ASSERT (FALSE);
 151     CpuDeadLoop ();
 152   }
 153 }