OvmfPkg: Add OVMF Mem Debug Log buffer to PEI mem cap/reserve early buffer

Add the memory debug log buffer size (pages) to
TotalPages in PlatformPei:GetPeiMemoryCap() help
ensure we don't run out of memory.

Also Reserve the "early" memory debug log buffer.

Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Aaron Young <aaron.young@oracle.com>

OvmfPkg/Library/PlatformInitLib/MemDetect.c

@@ -1504,6 +1504,20 @@ PlatformQemuInitializeRamForS3 (
         );
     }
 
+    if (FixedPcdGet32 (PcdOvmfEarlyMemDebugLogSize) != 0) {
+      //
+      // Reserve the Early Memory Debug Log buffer
+      //
+      // Since this memory range will be used on S3 resume, it must be
+      // reserved as ACPI NVS.
+      //
+      BuildMemoryAllocationHob (
+        (EFI_PHYSICAL_ADDRESS)(UINTN)FixedPcdGet32 (PcdOvmfEarlyMemDebugLogBase),
+        (UINT64)(UINTN)FixedPcdGet32 (PcdOvmfEarlyMemDebugLogSize),
+        PlatformInfoHob->S3Supported ? EfiACPIMemoryNVS : EfiBootServicesData
+        );
+    }
+
  #endif
   }
 }

OvmfPkg/Library/PlatformInitLib/PlatformInitLib.inf

@@ -107,5 +107,8 @@
   gUefiOvmfPkgTokenSpaceGuid.PcdOvmfFlashNvStorageVariableBase
   gUefiOvmfPkgTokenSpaceGuid.PcdCfvRawDataSize
 
+  gUefiOvmfPkgTokenSpaceGuid.PcdOvmfEarlyMemDebugLogBase
+  gUefiOvmfPkgTokenSpaceGuid.PcdOvmfEarlyMemDebugLogSize
+
 [FeaturePcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdDxeIplSwitchToLongMode

OvmfPkg/PlatformPei/MemDetect.c

@@ -29,6 +29,7 @@ Module Name:
 #include <Library/DebugLib.h>
 #include <Library/HobLib.h>
 #include <Library/IoLib.h>
+#include <Library/MemDebugLogLib.h>
 #include <Library/MemEncryptSevLib.h>
 #include <Library/PcdLib.h>
 #include <Library/PciLib.h>
@@ -250,6 +251,11 @@ GetPeiMemoryCap (
     ASSERT (TotalPages <= 0x404);
   }
 
+  //
+  // Add Memory Debug Log Buffer Pages (which can large)
+  //
+  TotalPages += MemDebugLogPages ();
+
   //
   // With 32k stacks and 4096 vcpus this lands at 128 MB (far away
   // from MAX_UINT32).

OvmfPkg/PlatformPei/PlatformPei.inf

@@ -72,6 +72,7 @@
   PlatformInitLib
   SmmRelocationLib
   TdxHelperLib
+  MemDebugLogLib
 
 [Pcd]
   gUefiOvmfPkgTokenSpaceGuid.PcdOvmfPeiMemFvBase