OvmfPkg/PlatformPei: ScanOrAdd64BitE820Ram improvements

Add a bool parameter to ScanOrAdd64BitE820Ram to explicitly specify
whenever ScanOrAdd64BitE820Ram should add HOBs for high memory (above
4G) or scan only.

Also add a lowmem parameter so ScanOrAdd64BitE820Ram
can report the memory size below 4G.

This allows a more flexible usage of ScanOrAdd64BitE820Ram,
a followup patch will use it for all memory detection.

No functional change.

Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3593
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>

1 files changed, 24 insertions, 8 deletions

diff --git a/OvmfPkg/PlatformPei/MemDetect.c b/OvmfPkg/PlatformPei/MemDetect.c
index 934d5c1965..b0b7e466a7 100644
--- a/OvmfPkg/PlatformPei/MemDetect.c
+++ b/OvmfPkg/PlatformPei/MemDetect.c
@@ -223,6 +223,8 @@ QemuUc32BaseInitialization (
 STATIC

 EFI_STATUS

 ScanOrAdd64BitE820Ram (

+  IN BOOLEAN  AddHighHob,

+  OUT UINT64  *LowMemory OPTIONAL,

   OUT UINT64  *MaxAddress OPTIONAL

   )

 {

@@ -241,6 +243,10 @@ ScanOrAdd64BitE820Ram (
     return EFI_PROTOCOL_ERROR;

   }

 

+  if (LowMemory != NULL) {

+    *LowMemory = 0;

+  }

+

   if (MaxAddress != NULL) {

     *MaxAddress = BASE_4GB;

   }

@@ -256,10 +262,8 @@ ScanOrAdd64BitE820Ram (
       E820Entry.Length,

       E820Entry.Type

       ));

-    if ((E820Entry.Type == EfiAcpiAddressRangeMemory) &&

-        (E820Entry.BaseAddr >= BASE_4GB))

-    {

-      if (MaxAddress == NULL) {

+    if (E820Entry.Type == EfiAcpiAddressRangeMemory) {

+      if (AddHighHob && (E820Entry.BaseAddr >= BASE_4GB)) {

         UINT64  Base;

         UINT64  End;

 

@@ -279,11 +283,13 @@ ScanOrAdd64BitE820Ram (
             End

             ));

         }

-      } else {

+      }

+

+      if (MaxAddress || LowMemory) {

         UINT64  Candidate;

 

         Candidate = E820Entry.BaseAddr + E820Entry.Length;

-        if (Candidate > *MaxAddress) {

+        if (MaxAddress && (Candidate > *MaxAddress)) {

           *MaxAddress = Candidate;

           DEBUG ((

             DEBUG_VERBOSE,

@@ -292,6 +298,16 @@ ScanOrAdd64BitE820Ram (
             *MaxAddress

             ));

         }

+

+        if (LowMemory && (Candidate > *LowMemory) && (Candidate < BASE_4GB)) {

+          *LowMemory = Candidate;

+          DEBUG ((

+            DEBUG_VERBOSE,

+            "%a: LowMemory=0x%Lx\n",

+            __FUNCTION__,

+            *LowMemory

+            ));

+        }

       }

     }

   }

@@ -376,7 +392,7 @@ GetFirstNonAddress (
   // Otherwise, get the flat size of the memory above 4GB from the CMOS (which

   // can only express a size smaller than 1TB), and add it to 4GB.

   //

-  Status = ScanOrAdd64BitE820Ram (&FirstNonAddress);

+  Status = ScanOrAdd64BitE820Ram (FALSE, NULL, &FirstNonAddress);

   if (EFI_ERROR (Status)) {

     FirstNonAddress = BASE_4GB + GetSystemMemorySizeAbove4gb ();

   }

@@ -809,7 +825,7 @@ QemuInitializeRam (
     // entries. Otherwise, create a single memory HOB with the flat >=4GB

     // memory size read from the CMOS.

     //

-    Status = ScanOrAdd64BitE820Ram (NULL);

+    Status = ScanOrAdd64BitE820Ram (TRUE, NULL, NULL);

     if (EFI_ERROR (Status) && (UpperMemorySize != 0)) {

       AddMemoryBaseSizeHob (BASE_4GB, UpperMemorySize);

     }