OvmfPkg/Include/Library/MemEncryptSevLib.h

   1 /** @file
   2
   3   Define Secure Encrypted Virtualization (SEV) base library helper function
   4
   5   Copyright (c) 2017 - 2020, AMD Incorporated. All rights reserved.<BR>
   6
   7   SPDX-License-Identifier: BSD-2-Clause-Patent
   8
   9 **/
  10
  11 #ifndef _MEM_ENCRYPT_SEV_LIB_H_
  12 #define _MEM_ENCRYPT_SEV_LIB_H_
  13
  14 #include <Base.h>
  15
  16 //
  17 // Internal structure for holding SEV-ES information needed during SEC phase
  18 // and valid only during SEC phase and early PEI during platform
  19 // initialization.
  20 //
  21 // This structure is also used by assembler files:
  22 //   OvmfPkg/ResetVector/ResetVector.nasmb
  23 //   OvmfPkg/ResetVector/Ia32/PageTables64.asm
  24 //   OvmfPkg/ResetVector/Ia32/Flat32ToFlat64.asm
  25 // any changes must stay in sync with its usage.
  26 //
  27 typedef struct _SEC_SEV_ES_WORK_AREA {
  28   UINT8    SevEsEnabled;
  29   UINT8    Reserved1[7];
  30
  31   UINT64   RandomData;
  32 } SEC_SEV_ES_WORK_AREA;
  33
  34 /**
  35   Returns a boolean to indicate whether SEV-ES is enabled.
  36
  37   @retval TRUE           SEV-ES is enabled
  38   @retval FALSE          SEV-ES is not enabled
  39 **/
  40 BOOLEAN
  41 EFIAPI
  42 MemEncryptSevEsIsEnabled (
  43   VOID
  44   );
  45
  46 /**
  47   Returns a boolean to indicate whether SEV is enabled
  48
  49   @retval TRUE           SEV is enabled
  50   @retval FALSE          SEV is not enabled
  51 **/
  52 BOOLEAN
  53 EFIAPI
  54 MemEncryptSevIsEnabled (
  55   VOID
  56   );
  57
  58 /**
  59   This function clears memory encryption bit for the memory region specified by
  60   BaseAddress and NumPages from the current page table context.
  61
  62   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  63                                       current CR3)
  64   @param[in]  BaseAddress             The physical address that is the start
  65                                       address of a memory region.
  66   @param[in]  NumPages                The number of pages from start memory
  67                                       region.
  68   @param[in]  Flush                   Flush the caches before clearing the bit
  69                                       (mostly TRUE except MMIO addresses)
  70
  71   @retval RETURN_SUCCESS              The attributes were cleared for the
  72                                       memory region.
  73   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  74   @retval RETURN_UNSUPPORTED          Clearing the memory encryption attribute
  75                                       is not supported
  76 **/
  77 RETURN_STATUS
  78 EFIAPI
  79 MemEncryptSevClearPageEncMask (
  80   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
  81   IN PHYSICAL_ADDRESS         BaseAddress,
  82   IN UINTN                    NumPages,
  83   IN BOOLEAN                  Flush
  84   );
  85
  86 /**
  87   This function sets memory encryption bit for the memory region specified by
  88   BaseAddress and NumPages from the current page table context.
  89
  90   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  91                                       current CR3)
  92   @param[in]  BaseAddress             The physical address that is the start
  93                                       address of a memory region.
  94   @param[in]  NumPages                The number of pages from start memory
  95                                       region.
  96   @param[in]  Flush                   Flush the caches before setting the bit
  97                                       (mostly TRUE except MMIO addresses)
  98
  99   @retval RETURN_SUCCESS              The attributes were set for the memory
 100                                       region.
 101   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
 102   @retval RETURN_UNSUPPORTED          Setting the memory encryption attribute
 103                                       is not supported
 104 **/
 105 RETURN_STATUS
 106 EFIAPI
 107 MemEncryptSevSetPageEncMask (
 108   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
 109   IN PHYSICAL_ADDRESS         BaseAddress,
 110   IN UINTN                    NumPages,
 111   IN BOOLEAN                  Flush
 112   );
 113
 114
 115 /**
 116   Locate the page range that covers the initial (pre-SMBASE-relocation) SMRAM
 117   Save State Map.
 118
 119   @param[out] BaseAddress     The base address of the lowest-address page that
 120                               covers the initial SMRAM Save State Map.
 121
 122   @param[out] NumberOfPages   The number of pages in the page range that covers
 123                               the initial SMRAM Save State Map.
 124
 125   @retval RETURN_SUCCESS      BaseAddress and NumberOfPages have been set on
 126                               output.
 127
 128   @retval RETURN_UNSUPPORTED  SMM is unavailable.
 129 **/
 130 RETURN_STATUS
 131 EFIAPI
 132 MemEncryptSevLocateInitialSmramSaveStateMapPages (
 133   OUT UINTN *BaseAddress,
 134   OUT UINTN *NumberOfPages
 135   );
 136 #endif // _MEM_ENCRYPT_SEV_LIB_H_