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
  36   by BaseAddress and Number of pages from the current page table context.
  37
  38   @param[in]  BaseAddress           The physical address that is the start
  39                                     address of a memory region.
  40   @param[in]  NumberOfPages         The number of pages from start memory
  41                                     region.
  42   @param[in]  Flush                 Flush the caches before clearing the bit
  43                                     (mostly TRUE except MMIO addresses)
  44
  45   @retval RETURN_SUCCESS            The attributes were cleared for the memory
  46                                     region.
  47   @retval RETURN_INVALID_PARAMETER  Number of pages is zero.
  48   @retval RETURN_UNSUPPORTED        Clearing memory encryption attribute is not
  49                                     supported
  50   **/
  51 RETURN_STATUS
  52 EFIAPI
  53 MemEncryptSevClearPageEncMask (
  54   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
  55   IN PHYSICAL_ADDRESS         BaseAddress,
  56   IN UINTN                    NumberOfPages,
  57   IN BOOLEAN                  CacheFlush
  58   );
  59
  60 /**
  61   This function sets memory encryption bit for the memory region specified by
  62   BaseAddress and Number of pages from the current page table context.
  63
  64   @param[in]  BaseAddress           The physical address that is the start
  65                                     address of a memory region.
  66   @param[in]  NumberOfPages         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 set for the memory
  72                                     region.
  73   @retval RETURN_INVALID_PARAMETER  Number of pages is zero.
  74   @retval RETURN_UNSUPPORTED        Clearing memory encryption attribute is not
  75                                     supported
  76   **/
  77 RETURN_STATUS
  78 EFIAPI
  79 MemEncryptSevSetPageEncMask (
  80   IN PHYSICAL_ADDRESS         Cr3BaseAddress,
  81   IN PHYSICAL_ADDRESS         BaseAddress,
  82   IN UINTN                    NumberOfPages,
  83   IN BOOLEAN                  CacheFlush
  84   );
  85 #endif // _MEM_ENCRYPT_SEV_LIB_H_