OvmfPkg/Include/Library/MemEncryptSevLib.h

   1 /** @file
   2
   3   Define Secure Encrypted Virtualization (SEV) base library helper function
   4
   5   Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
   6
   7   This program and the accompanying materials are licensed and made available
   8   under the terms and conditions of the BSD License which accompanies this
   9   distribution.  The full text of the license may be found at
  10   http://opensource.org/licenses/bsd-license.php
  11
  12   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 #ifndef _MEM_ENCRYPT_SEV_LIB_H_
  18 #define _MEM_ENCRYPT_SEV_LIB_H_
  19
  20 #include <Base.h>
  21
  22 /**
  23   Returns a boolean to indicate whether SEV is enabled
  24
  25   @retval TRUE           SEV is enabled
  26   @retval FALSE          SEV is not enabled
  27 **/
  28 BOOLEAN
  29 EFIAPI
  30 MemEncryptSevIsEnabled (
  31   VOID
  32   );
  33
  34 /**
  35   This function clears memory encryption bit for the memory region specified by
  36   BaseAddress and NumPages from the current page table context.
  37
  38   @param[in]  Cr3BaseAddress          Cr3 Base Address (if zero then use
  39                                       current CR3)
  40   @param[in]  BaseAddress             The physical address that is the start
  41                                       address of a memory region.
  42   @param[in]  NumPages                The number of pages from start memory
  43                                       region.
  44   @param[in]  Flush                   Flush the caches before clearing the bit
  45                                       (mostly TRUE except MMIO addresses)
  46
  47   @retval RETURN_SUCCESS              The attributes were cleared for the
  48                                       memory region.
  49   @retval RETURN_INVALID_PARAMETER    Number of pages is zero.
  50   @retval RETURN_UNSUPPORTED          Clearing the memory encryption attribute
  51                                       is not supported
  52 **/
  53 RETURN_STATUS
  54 EFIAPI
  55 MemEncryptSevClearPageEncMask (
  56   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
  57   IN PHYSICAL_ADDRESS         BaseAddress,
  58   IN UINTN                    NumPages,
  59   IN BOOLEAN                  Flush
  60   );
  61
  62 /**
  63   This function sets memory encryption bit for the memory region specified by
  64   BaseAddress and Number of pages from the current page table context.
  65
  66   @param[in]  BaseAddress           The physical address that is the start
  67                                     address of a memory region.
  68   @param[in]  NumberOfPages         The number of pages from start memory
  69                                     region.
  70   @param[in]  Flush                 Flush the caches before clearing the bit
  71                                     (mostly TRUE except MMIO addresses)
  72
  73   @retval RETURN_SUCCESS            The attributes were set for the memory
  74                                     region.
  75   @retval RETURN_INVALID_PARAMETER  Number of pages is zero.
  76   @retval RETURN_UNSUPPORTED        Clearing memory encryption attribute is not
  77                                     supported
  78   **/
  79 RETURN_STATUS
  80 EFIAPI
  81 MemEncryptSevSetPageEncMask (
  82   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
  83   IN PHYSICAL_ADDRESS         BaseAddress,
  84   IN UINTN                    NumberOfPages,
  85   IN BOOLEAN                  CacheFlush
  86   );
  87 #endif // _MEM_ENCRYPT_SEV_LIB_H_