OvmfPkg/Library/BaseMemEncryptSevLib/X64/MemEncryptSevLib.c

   1 /** @file
   2
   3   Secure Encrypted Virtualization (SEV) library helper function
   4
   5   Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
   6
   7   SPDX-License-Identifier: BSD-2-Clause-Patent
   8
   9 **/
  10
  11 #include <Library/BaseLib.h>
  12 #include <Library/DebugLib.h>
  13 #include <Library/MemEncryptSevLib.h>
  14 #include <Register/Amd/Cpuid.h>
  15 #include <Register/Amd/Msr.h>
  16 #include <Register/Cpuid.h>
  17
  18 #include "VirtualMemory.h"
  19
  20 /**
  21   This function clears memory encryption bit for the memory region specified by
  22   BaseAddress and NumPages from the current page table context.
  23
  24   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  25                                       current CR3)
  26   @param[in]  BaseAddress             The physical address that is the start
  27                                       address of a memory region.
  28   @param[in]  NumPages                The number of pages from start memory
  29                                       region.
  30   @param[in]  Flush                   Flush the caches before clearing the bit
  31                                       (mostly TRUE except MMIO addresses)
  32
  33   @retval RETURN_SUCCESS              The attributes were cleared for the
  34                                       memory region.
  35   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  36   @retval RETURN_UNSUPPORTED          Clearing the memory encryption attribute
  37                                       is not supported
  38 **/
  39 RETURN_STATUS
  40 EFIAPI
  41 MemEncryptSevClearPageEncMask (
  42   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
  43   IN PHYSICAL_ADDRESS         BaseAddress,
  44   IN UINTN                    NumPages,
  45   IN BOOLEAN                  Flush
  46   )
  47 {
  48   return InternalMemEncryptSevSetMemoryDecrypted (
  49            Cr3BaseAddress,
  50            BaseAddress,
  51            EFI_PAGES_TO_SIZE (NumPages),
  52            Flush
  53            );
  54 }
  55
  56 /**
  57   This function sets memory encryption bit for the memory region specified by
  58   BaseAddress and NumPages from the current page table context.
  59
  60   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  61                                       current CR3)
  62   @param[in]  BaseAddress             The physical address that is the start
  63                                       address of a memory region.
  64   @param[in]  NumPages                The number of pages from start memory
  65                                       region.
  66   @param[in]  Flush                   Flush the caches before setting the bit
  67                                       (mostly TRUE except MMIO addresses)
  68
  69   @retval RETURN_SUCCESS              The attributes were set for the memory
  70                                       region.
  71   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  72   @retval RETURN_UNSUPPORTED          Setting the memory encryption attribute
  73                                       is not supported
  74 **/
  75 RETURN_STATUS
  76 EFIAPI
  77 MemEncryptSevSetPageEncMask (
  78   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
  79   IN PHYSICAL_ADDRESS         BaseAddress,
  80   IN UINTN                    NumPages,
  81   IN BOOLEAN                  Flush
  82   )
  83 {
  84   return InternalMemEncryptSevSetMemoryEncrypted (
  85            Cr3BaseAddress,
  86            BaseAddress,
  87            EFI_PAGES_TO_SIZE (NumPages),
  88            Flush
  89            );
  90 }