Create memory map entries for VGA RAM & ROM space, fix memory parsing

 - Extend reserved memory range to include the VGA ROM space (0xc0000-0xdffff)
 - Create memory map entries for these ranges
 - Fix parsing of memory ranges that overlap VGA space (more dynamic)

Signed-off-by: Alex Williamson <alex.williamson@xxxxxx>
---

diff -r 7988fb818c3b edk2-sparse/EdkXenPkg/Dxe/Bds/BdsPlatform.c
--- a/edk2-sparse/EdkXenPkg/Dxe/Bds/BdsPlatform.c	Wed Aug 29 04:11:05 2007 +0200
+++ b/edk2-sparse/EdkXenPkg/Dxe/Bds/BdsPlatform.c	Tue Oct 09 14:54:55 2007 -0600
@@ -107,6 +107,20 @@ struct _PLATFORM_MEMORY_DESC {
 
 typedef struct _PLATFORM_MEMORY_DESC PLATFORM_MEMORY_DESC;
 STATIC PLATFORM_MEMORY_DESC PlatformMemory[] = {
+ {
+    0xa0000,
+    0x20000,
+    EfiGcdMemoryTypeMemoryMappedIo,
+    EfiMemoryMappedIO,
+    EFI_MEMORY_UC | EFI_MEMORY_WC | EFI_MEMORY_UCE | EFI_MEMORY_RUNTIME
+  },
+ {
+    0xc0000,
+    0x20000,
+    EfiGcdMemoryTypeSystemMemory,
+    EfiReservedMemoryType,
+    EFI_MEMORY_UC
+  },
  {
     0xc0000000,
     0x20000000,
diff -r 7988fb818c3b edk2-sparse/EdkXenPkg/Pei/XenMemoryScan/XenMemoryScan.c
--- a/edk2-sparse/EdkXenPkg/Pei/XenMemoryScan/XenMemoryScan.c	Wed Aug 29 04:11:05 2007 +0200
+++ b/edk2-sparse/EdkXenPkg/Pei/XenMemoryScan/XenMemoryScan.c	Wed Oct 10 11:08:34 2007 -0600
@@ -19,6 +19,10 @@ Revision History
 
 --*/
 #include <Ppi/XenHobs.h>
+
+#define Min(a, b) ((a) < (b) ? (a) : (b))
+#define VGA_BASE 0xA0000
+#define VGA_END  0xE0000
 
 STATIC
 VOID
@@ -97,37 +101,41 @@ Returns:
       data = (UINT64 *)(hdr + 1);
       data_len = hdr->length - sizeof (struct XenHobHeader);
       if (hdr->type == HOB_TYPE_MEM && data_len == 16) {
-		  Base = data[0];
-		  Len = data[1];
-		  if (Base == 0)
-		  {
-			  UINT64 mem_start = Base;
-			  UINT64 mem_len = 0xa0000;
+        Base = data[0];
+        Len = data[1];
 
-			  RegisterMemoryArea(PeiServices, mem_start, mem_len);
-			  DEBUG((EFI_D_ERROR, "Build memory hob at 0x%lx, len is 0x%lx\n", mem_start, mem_len));
+        //
+        // Don't register memory area for VGA hole:
+        // VGA RAM (0xA0000 ~ 0xBFFFF) + VGA ROM (0xC0000 ~ 0xDFFFF)
+        //
+        if (Base < VGA_END && (Base + Len) >= VGA_BASE) {
+          UINT64 mem_start;
+          UINT64 mem_len;
 
-			  /* Don't register memory area for VGA hole(0xa0000 ~ 0xc0000)*/
-			  mem_start = 0xc0000;
-			  mem_len = 0x100000 - 0xc0000;
+          if (Base < VGA_BASE) {
+            mem_start = Base;
+            mem_len = VGA_BASE - Base;
 
-			  RegisterMemoryArea(PeiServices, mem_start, mem_len);
-			  DEBUG((EFI_D_ERROR, "Build memory hob at 0x%lx, len is 0x%lx\n", mem_start, mem_len));
+            RegisterMemoryArea(PeiServices, mem_start, mem_len);
+            DEBUG((EFI_D_ERROR, "Build memory hob at 0x%lx, len is 0x%lx\n",
+                   mem_start, mem_len));
+          }
 
-			  mem_start = 0x100000;
-			  mem_len = Len - 0x100000;
+          if (Base + Len > VGA_END) {
+            mem_start = VGA_END;
+            mem_len = (Base + Len) - VGA_END;
 
-			  RegisterMemoryArea(PeiServices, mem_start, mem_len);
-			  DEBUG((EFI_D_ERROR, "Build memory hob at 0x%lx, len is 0x%lx\n", mem_start, mem_len));
-
-		  }
-		  else
-		  {
-			  RegisterMemoryArea(PeiServices, Base, Len);
-			  DEBUG((EFI_D_ERROR, "Build memory hob at 0x%lx, len is 0x%lx\n", Base, Len));
-		  }
-	  }
-	  hob += hdr->length;
+            RegisterMemoryArea(PeiServices, mem_start, mem_len);
+            DEBUG((EFI_D_ERROR, "Build memory hob at 0x%lx, len is 0x%lx\n",
+                   mem_start, mem_len));
+          }
+        } else {
+          RegisterMemoryArea(PeiServices, Base, Len);
+          DEBUG((EFI_D_ERROR, "Build memory hob at 0x%lx, len is 0x%lx\n",
+                 Base, Len));
+        }
+      }
+      hob += hdr->length;
     }
   while (hdr->type != HOB_TYPE_TERMINAL);