OvmfPkg/PlatformPei: stop using cmos for memory detection

[mirror_edk2.git] / OvmfPkg / PlatformPei / MemDetect.c

diff --git a/OvmfPkg/PlatformPei/MemDetect.c b/OvmfPkg/PlatformPei/MemDetect.c
index 1bcb5a08bca640e24ed1cf9ea0e81e7114f10328..fb38e3c39d8ee49c09eb64b1100b6b1d63c8b467 100644 (file)
--- a/OvmfPkg/PlatformPei/MemDetect.c
+++ b/OvmfPkg/PlatformPei/MemDetect.c
@@ -38,7 +38,6 @@ Module Name:
 #include <Library/QemuFwCfgSimpleParserLib.h>\r
 \r
 #include "Platform.h"\r
-#include "Cmos.h"\r
 \r
 UINT8  mPhysMemAddressWidth;\r
 \r
@@ -322,51 +321,11 @@ GetSystemMemorySizeBelow4gb (
 {\r
   EFI_STATUS  Status;\r
   UINT64      LowerMemorySize = 0;\r
-  UINT8       Cmos0x34;\r
-  UINT8       Cmos0x35;\r
 \r
   Status = ScanOrAdd64BitE820Ram (FALSE, &LowerMemorySize, NULL);\r
-  if ((Status == EFI_SUCCESS) && (LowerMemorySize > 0)) {\r
-    return (UINT32)LowerMemorySize;\r
-  }\r
-\r
-  //\r
-  // CMOS 0x34/0x35 specifies the system memory above 16 MB.\r
-  // * CMOS(0x35) is the high byte\r
-  // * CMOS(0x34) is the low byte\r
-  // * The size is specified in 64kb chunks\r
-  // * Since this is memory above 16MB, the 16MB must be added\r
-  //   into the calculation to get the total memory size.\r
-  //\r
-\r
-  Cmos0x34 = (UINT8)CmosRead8 (0x34);\r
-  Cmos0x35 = (UINT8)CmosRead8 (0x35);\r
-\r
-  return (UINT32)(((UINTN)((Cmos0x35 << 8) + Cmos0x34) << 16) + SIZE_16MB);\r
-}\r
-\r
-STATIC\r
-UINT64\r
-GetSystemMemorySizeAbove4gb (\r
-  )\r
-{\r
-  UINT32  Size;\r
-  UINTN   CmosIndex;\r
-\r
-  //\r
-  // CMOS 0x5b-0x5d specifies the system memory above 4GB MB.\r
-  // * CMOS(0x5d) is the most significant size byte\r
-  // * CMOS(0x5c) is the middle size byte\r
-  // * CMOS(0x5b) is the least significant size byte\r
-  // * The size is specified in 64kb chunks\r
-  //\r
-\r
-  Size = 0;\r
-  for (CmosIndex = 0x5d; CmosIndex >= 0x5b; CmosIndex--) {\r
-    Size = (UINT32)(Size << 8) + (UINT32)CmosRead8 (CmosIndex);\r
-  }\r
-\r
-  return LShiftU64 (Size, 16);\r
+  ASSERT_EFI_ERROR (Status);\r
+  ASSERT (LowerMemorySize > 0);\r
+  return (UINT32)LowerMemorySize;\r
 }\r
 \r
 /**\r
@@ -396,12 +355,9 @@ GetFirstNonAddress (
   // If QEMU presents an E820 map, then get the highest exclusive >=4GB RAM\r
   // address from it. This can express an address >= 4GB+1TB.\r
   //\r
-  // Otherwise, get the flat size of the memory above 4GB from the CMOS (which\r
-  // can only express a size smaller than 1TB), and add it to 4GB.\r
-  //\r
   Status = ScanOrAdd64BitE820Ram (FALSE, NULL, &FirstNonAddress);\r
   if (EFI_ERROR (Status)) {\r
-    FirstNonAddress = BASE_4GB + GetSystemMemorySizeAbove4gb ();\r
+    FirstNonAddress = BASE_4GB;\r
   }\r
 \r
   //\r
@@ -773,7 +729,6 @@ QemuInitializeRam (
   )\r
 {\r
   UINT64         LowerMemorySize;\r
-  UINT64         UpperMemorySize;\r
   MTRR_SETTINGS  MtrrSettings;\r
   EFI_STATUS     Status;\r
 \r
@@ -832,12 +787,6 @@ QemuInitializeRam (
     // memory size read from the CMOS.\r
     //\r
     Status = ScanOrAdd64BitE820Ram (TRUE, NULL, NULL);\r
-    if (EFI_ERROR (Status)) {\r
-      UpperMemorySize = GetSystemMemorySizeAbove4gb ();\r
-      if (UpperMemorySize != 0) {\r
-        AddMemoryBaseSizeHob (BASE_4GB, UpperMemorySize);\r
-      }\r
-    }\r
   }\r
 \r
   //\r