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 // any changes must stay in sync with its usage.
  25 //
  26 typedef struct _SEC_SEV_ES_WORK_AREA {
  27   UINT8    SevEsEnabled;
  28 } SEC_SEV_ES_WORK_AREA;
  29
  30 /**
  31   Returns a boolean to indicate whether SEV-ES is enabled.
  32
  33   @retval TRUE           SEV-ES is enabled
  34   @retval FALSE          SEV-ES is not enabled
  35 **/
  36 BOOLEAN
  37 EFIAPI
  38 MemEncryptSevEsIsEnabled (
  39   VOID
  40   );
  41
  42 /**
  43   Returns a boolean to indicate whether SEV is enabled
  44
  45   @retval TRUE           SEV is enabled
  46   @retval FALSE          SEV is not enabled
  47 **/
  48 BOOLEAN
  49 EFIAPI
  50 MemEncryptSevIsEnabled (
  51   VOID
  52   );
  53
  54 /**
  55   This function clears memory encryption bit for the memory region specified by
  56   BaseAddress and NumPages from the current page table context.
  57
  58   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  59                                       current CR3)
  60   @param[in]  BaseAddress             The physical address that is the start
  61                                       address of a memory region.
  62   @param[in]  NumPages                The number of pages from start memory
  63                                       region.
  64   @param[in]  Flush                   Flush the caches before clearing the bit
  65                                       (mostly TRUE except MMIO addresses)
  66
  67   @retval RETURN_SUCCESS              The attributes were cleared for the
  68                                       memory region.
  69   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  70   @retval RETURN_UNSUPPORTED          Clearing the memory encryption attribute
  71                                       is not supported
  72 **/
  73 RETURN_STATUS
  74 EFIAPI
  75 MemEncryptSevClearPageEncMask (
  76   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
  77   IN PHYSICAL_ADDRESS         BaseAddress,
  78   IN UINTN                    NumPages,
  79   IN BOOLEAN                  Flush
  80   );
  81
  82 /**
  83   This function sets memory encryption bit for the memory region specified by
  84   BaseAddress and NumPages from the current page table context.
  85
  86   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  87                                       current CR3)
  88   @param[in]  BaseAddress             The physical address that is the start
  89                                       address of a memory region.
  90   @param[in]  NumPages                The number of pages from start memory
  91                                       region.
  92   @param[in]  Flush                   Flush the caches before setting the bit
  93                                       (mostly TRUE except MMIO addresses)
  94
  95   @retval RETURN_SUCCESS              The attributes were set for the memory
  96                                       region.
  97   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  98   @retval RETURN_UNSUPPORTED          Setting the memory encryption attribute
  99                                       is not supported
 100 **/
 101 RETURN_STATUS
 102 EFIAPI
 103 MemEncryptSevSetPageEncMask (
 104   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
 105   IN PHYSICAL_ADDRESS         BaseAddress,
 106   IN UINTN                    NumPages,
 107   IN BOOLEAN                  Flush
 108   );
 109
 110
 111 /**
 112   Locate the page range that covers the initial (pre-SMBASE-relocation) SMRAM
 113   Save State Map.
 114
 115   @param[out] BaseAddress     The base address of the lowest-address page that
 116                               covers the initial SMRAM Save State Map.
 117
 118   @param[out] NumberOfPages   The number of pages in the page range that covers
 119                               the initial SMRAM Save State Map.
 120
 121   @retval RETURN_SUCCESS      BaseAddress and NumberOfPages have been set on
 122                               output.
 123
 124   @retval RETURN_UNSUPPORTED  SMM is unavailable.
 125 **/
 126 RETURN_STATUS
 127 EFIAPI
 128 MemEncryptSevLocateInitialSmramSaveStateMapPages (
 129   OUT UINTN *BaseAddress,
 130   OUT UINTN *NumberOfPages
 131   );
 132 #endif // _MEM_ENCRYPT_SEV_LIB_H_