OvmfPkg/igvm: add igvm memory map support.

In case a IGVM memory map is present in the parameter area use that
when detecting guest memory.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

OvmfPkg/Include/Library/PlatformInitLib.h

@@ -10,6 +10,7 @@
 #define PLATFORM_INIT_LIB_H_
 
 #include <PiPei.h>
+#include <IndustryStandard/E820.h>
 
 #pragma pack(1)
 
@@ -290,4 +291,22 @@ PlatformInitEmuVariableNvStore (
   IN VOID  *EmuVariableNvStore
   );
 
+typedef VOID (*E820_SCAN_CALLBACK) (
+  EFI_E820_ENTRY64       *E820Entry,
+  EFI_HOB_PLATFORM_INFO  *PlatformInfoHob
+  );
+
+BOOLEAN
+EFIAPI
+PlatformIgvmMemoryMapCheck (
+  VOID
+  );
+
+EFI_STATUS
+EFIAPI
+PlatformIgvmScanE820 (
+  IN      E820_SCAN_CALLBACK     Callback,
+  IN OUT  EFI_HOB_PLATFORM_INFO  *PlatformInfoHob
+  );
+
 #endif // PLATFORM_INIT_LIB_H_

OvmfPkg/Library/PlatformInitLib/Igvm.c

@@ -0,0 +1,110 @@
+/** @file
+  IGVM Parameter parsing
+
+  Copyright (c) 2006 - 2009, Intel Corporation. All rights reserved.<BR>
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Library/PlatformInitLib.h>
+#include <Library/DebugLib.h>
+
+/* keep in sync with OvmfPkg/ResetVector/X64/IgvmMetadata.asm */
+#define MEMORY_MAP_OFFSET   0
+#define MEMORY_MAP_ENTRIES  8
+#define MEMORY_MAP_SIZE     (MEMORY_MAP_ENTRIES * sizeof(IGVM_MEMORY_MAP_ENTRY))
+
+#define IGVM_MM_ENTRY_TYPE_MEMORY      0x00
+#define IGVM_MM_ENTRY_TYPE_RESERVED    0x01
+#define IGVM_MM_ENTRY_TYPE_PERSISTENT  0x02
+
+typedef struct IGVM_MEMORY_MAP_ENTRY {
+  UINT64    PageStart;
+  UINT64    PageCount;
+  UINT16    EntryType;
+  UINT16    EntryFlags;
+  UINT32    Reserved;
+} IGVM_MEMORY_MAP_ENTRY;
+
+STATIC
+IGVM_MEMORY_MAP_ENTRY *
+EFIAPI
+PlatformIgvmMemoryMapFind (
+  VOID
+  )
+{
+  UINT64                 Address;
+  IGVM_MEMORY_MAP_ENTRY  *Map;
+
+  Address = FixedPcdGet64 (PcdOvmfIgvmParamBase);
+  if (Address == 0) {
+    // no parameter area
+    return NULL;
+  }
+
+  Map = (VOID *)(UINTN)(Address + MEMORY_MAP_OFFSET);
+  if (Map[0].PageCount == 0) {
+    // no memory map entries
+    return NULL;
+  }
+
+  return Map;
+}
+
+BOOLEAN
+EFIAPI
+PlatformIgvmMemoryMapCheck (
+  VOID
+  )
+{
+  return PlatformIgvmMemoryMapFind () != NULL;
+}
+
+EFI_STATUS
+EFIAPI
+PlatformIgvmScanE820 (
+  IN      E820_SCAN_CALLBACK     Callback,
+  IN OUT  EFI_HOB_PLATFORM_INFO  *PlatformInfoHob
+  )
+{
+  STATIC BOOLEAN         First = TRUE;
+  IGVM_MEMORY_MAP_ENTRY  *Map;
+  EFI_E820_ENTRY64       Entry;
+  UINT32                 Index;
+
+  Map = PlatformIgvmMemoryMapFind ();
+
+  if (Map == NULL) {
+    return EFI_NOT_FOUND;
+  }
+
+  for (Index = 0; Map[Index].PageCount > 0; Index++) {
+    if (First) {
+      DEBUG ((
+        DEBUG_INFO,
+        "%a: IgvmMemoryMap[%d]: PageStart %lx, PageCount %lx, EntryType %d\n",
+        __func__,
+        Index,
+        Map[Index].PageStart,
+        Map[Index].PageCount,
+        Map[Index].EntryType
+        ));
+    }
+
+    Entry.BaseAddr = LShiftU64 (Map[Index].PageStart, EFI_PAGE_SHIFT);
+    Entry.Length   = LShiftU64 (Map[Index].PageCount, EFI_PAGE_SHIFT);
+    switch (Map[Index].EntryType) {
+      case IGVM_MM_ENTRY_TYPE_MEMORY:
+        Entry.Type = EfiAcpiAddressRangeMemory;
+        Callback (&Entry, PlatformInfoHob);
+        break;
+      case IGVM_MM_ENTRY_TYPE_RESERVED:
+        Entry.Type = EfiAcpiAddressRangeReserved;
+        Callback (&Entry, PlatformInfoHob);
+        break;
+    }
+  }
+
+  First = FALSE;
+  return EFI_SUCCESS;
+}

OvmfPkg/Library/PlatformInitLib/MemDetect.c

@@ -102,11 +102,6 @@ PlatformQemuUc32BaseInitialization (
   }
 }
 
-typedef VOID (*E820_SCAN_CALLBACK) (
-  EFI_E820_ENTRY64       *E820Entry,
-  EFI_HOB_PLATFORM_INFO  *PlatformInfoHob
-  );
-
 STATIC
 EFI_STATUS
 PlatformScanE820Tdx (
@@ -373,6 +368,10 @@ PlatformScanE820 (
   EFI_E820_ENTRY64      E820Entry;
   UINTN                 Processed;
 
+  if (PlatformIgvmMemoryMapCheck ()) {
+    return PlatformIgvmScanE820 (Callback, PlatformInfoHob);
+  }
+
   if (PlatformInfoHob->HostBridgeDevId == CLOUDHV_DEVICE_ID) {
     return PlatformScanE820Pvh (Callback, PlatformInfoHob);
   }

OvmfPkg/Library/PlatformInitLib/PlatformInitLib.inf

@@ -24,6 +24,7 @@
 
 [Sources]
   Cmos.c
+  Igvm.c
   MemDetect.c
   Platform.c
 
@@ -110,5 +111,7 @@
   gUefiOvmfPkgTokenSpaceGuid.PcdOvmfEarlyMemDebugLogBase
   gUefiOvmfPkgTokenSpaceGuid.PcdOvmfEarlyMemDebugLogSize
 
+  gUefiOvmfPkgTokenSpaceGuid.PcdOvmfIgvmParamBase
+
 [FeaturePcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdDxeIplSwitchToLongMode

OvmfPkg/ResetVector/X64/IgvmMetadata.asm

@@ -15,6 +15,7 @@ ALIGN 16
 
 %define IGVM_ID_HOB_AREA                                 0x200
 
+; keep in sync with OvmfPkg/Library/PlatformInitLib/Igvm.c
 %define MEMORY_MAP_OFFSET                                    0
 %define MEMORY_MAP_ENTRIES                                   8
 %define MEMORY_MAP_SIZE              (MEMORY_MAP_ENTRIES * 24)