3 Secure Encrypted Virtualization (SEV) library helper function
5 Copyright (c) 2017, AMD Incorporated. All rights reserved.<BR>
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
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.
17 #include <Library/BaseLib.h>
18 #include <Library/DebugLib.h>
19 #include <Register/Cpuid.h>
20 #include <Register/Amd/Cpuid.h>
21 #include <Register/Amd/Msr.h>
22 #include <Library/MemEncryptSevLib.h>
25 This function clears memory encryption bit for the memory region specified
26 by BaseAddress and Number of pages from the current page table context.
28 @param[in] Cr3BaseAddress Cr3 Base Address (if zero then use current
30 @param[in] BaseAddress The physical address that is the start
31 address of a memory region.
32 @param[in] NumberOfPages The number of pages from start memory
34 @param[in] Flush Flush the caches before clearing the bit
35 (mostly TRUE except MMIO addresses)
37 @retval RETURN_SUCCESS The attributes were cleared for the memory
39 @retval RETURN_INVALID_PARAMETER Number of pages is zero.
40 @retval RETURN_UNSUPPORTED Clearing memory encryption attribute is not
45 MemEncryptSevClearPageEncMask (
46 IN PHYSICAL_ADDRESS Cr3BaseAddress
,
47 IN PHYSICAL_ADDRESS BaseAddress
,
48 IN UINTN NumberOfPages
,
53 // Memory encryption bit is not accessible in 32-bit mode
55 return RETURN_UNSUPPORTED
;
59 This function sets memory encryption bit for the memory region specified by
60 BaseAddress and Number of pages from the current page table context.
62 @param[in] Cr3BaseAddress Cr3 Base Address (if zero then use current
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
68 @param[in] Flush Flush the caches before clearing the bit
69 (mostly TRUE except MMIO addresses)
71 @retval RETURN_SUCCESS The attributes were set for the memory
73 @retval RETURN_INVALID_PARAMETER Number of pages is zero.
74 @retval RETURN_UNSUPPORTED Clearing memory encryption attribute is not
79 MemEncryptSevSetPageEncMask (
80 IN PHYSICAL_ADDRESS Cr3BaseAddress
,
81 IN PHYSICAL_ADDRESS BaseAddress
,
82 IN UINTN NumberOfPages
,
87 // Memory encryption bit is not accessible in 32-bit mode
89 return RETURN_UNSUPPORTED
;