2 Memory Detection for Virtual Machines.
4 Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>
5 This program and the accompanying materials
6 are licensed and made available under the terms and conditions of the BSD License
7 which accompanies this distribution. The full text of the license may be found at
8 http://opensource.org/licenses/bsd-license.php
10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
20 // The package level header files this module uses
25 // The Library classes this module consumes
27 #include <Library/DebugLib.h>
28 #include <Library/HobLib.h>
29 #include <Library/IoLib.h>
30 #include <Library/PcdLib.h>
31 #include <Library/PeimEntryPoint.h>
32 #include <Library/ResourcePublicationLib.h>
33 #include <Library/MtrrLib.h>
40 GetSystemMemorySizeBelow4gb (
47 // CMOS 0x34/0x35 specifies the system memory above 16 MB.
48 // * CMOS(0x35) is the high byte
49 // * CMOS(0x34) is the low byte
50 // * The size is specified in 64kb chunks
51 // * Since this is memory above 16MB, the 16MB must be added
52 // into the calculation to get the total memory size.
55 Cmos0x34
= (UINT8
) CmosRead8 (0x34);
56 Cmos0x35
= (UINT8
) CmosRead8 (0x35);
58 return (((UINTN
)((Cmos0x35
<< 8) + Cmos0x34
) << 16) + SIZE_16MB
);
64 GetSystemMemorySizeAbove4gb (
71 // CMOS 0x5b-0x5d specifies the system memory above 4GB MB.
72 // * CMOS(0x5d) is the most significant size byte
73 // * CMOS(0x5c) is the middle size byte
74 // * CMOS(0x5b) is the least significant size byte
75 // * The size is specified in 64kb chunks
79 for (CmosIndex
= 0x5d; CmosIndex
>= 0x5b; CmosIndex
--) {
80 Size
= (UINT32
) (Size
<< 8) + (UINT32
) CmosRead8 (CmosIndex
);
83 return LShiftU64 (Size
, 16);
88 Peform Memory Detection
90 @return EFI_SUCCESS The PEIM initialized successfully.
98 EFI_PHYSICAL_ADDRESS MemoryBase
;
100 UINT64 LowerMemorySize
;
101 UINT64 UpperMemorySize
;
103 DEBUG ((EFI_D_ERROR
, "MemDetect called\n"));
106 // Determine total memory size available
108 LowerMemorySize
= GetSystemMemorySizeBelow4gb ();
109 UpperMemorySize
= GetSystemMemorySizeAbove4gb ();
112 // Determine the range of memory to use during PEI
114 MemoryBase
= PcdGet32 (PcdOvmfMemFvBase
) + PcdGet32 (PcdOvmfMemFvSize
);
115 MemorySize
= LowerMemorySize
- MemoryBase
;
116 if (MemorySize
> SIZE_64MB
) {
117 MemoryBase
= LowerMemorySize
- SIZE_64MB
;
118 MemorySize
= SIZE_64MB
;
122 // Publish this memory to the PEI Core
124 Status
= PublishSystemMemory(MemoryBase
, MemorySize
);
125 ASSERT_EFI_ERROR (Status
);
128 // Create memory HOBs
130 AddMemoryBaseSizeHob (MemoryBase
, MemorySize
);
131 AddMemoryRangeHob (BASE_1MB
, MemoryBase
);
132 AddMemoryRangeHob (0, BASE_512KB
+ BASE_128KB
);
134 MtrrSetMemoryAttribute (BASE_1MB
, MemoryBase
+ MemorySize
- BASE_1MB
, CacheWriteBack
);
136 MtrrSetMemoryAttribute (0, BASE_512KB
+ BASE_128KB
, CacheWriteBack
);
138 if (UpperMemorySize
!= 0) {
139 AddUntestedMemoryBaseSizeHob (BASE_4GB
, UpperMemorySize
);
141 MtrrSetMemoryAttribute (BASE_4GB
, UpperMemorySize
, CacheWriteBack
);
144 return MemoryBase
+ MemorySize
;