Xen devel - Nov 2013 - [PATCH RFC 4/7] OvmfPkg: extract OVMF info passed by Xen hvmloader

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
---
 OvmfPkg/PlatformPei/Xen.c |   31 +++++++++++++++++++++++++++++++
 1 file changed, 31 insertions(+)

diff --git a/OvmfPkg/PlatformPei/Xen.c b/OvmfPkg/PlatformPei/Xen.c
index a720b91..b4c1247 100644
--- a/OvmfPkg/PlatformPei/Xen.c
+++ b/OvmfPkg/PlatformPei/Xen.c
@@ -26,12 +26,15 @@
 #include <Library/HobLib.h>
 #include <Library/MemoryAllocationLib.h>
 #include <Library/PcdLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <IndustryStandard/E820.h>
 #include <Guid/XenInfo.h>
 
 #include "Platform.h"
 
 EFI_XEN_INFO mXenInfo;
 
+#define OVMF_INFO_PHYSICAL_ADDRESS 0x00001000
 
 /**
   Connects to the Hypervisor.
@@ -50,6 +53,9 @@ XenConnect (
   UINT32 TransferReg;
   UINT32 TransferPages;
   UINT32 XenVersion;
+  EFI_XEN_OVMF_INFO *Info = (EFI_XEN_OVMF_INFO *) OVMF_INFO_PHYSICAL_ADDRESS;
+
+  ZeroMem (&mXenInfo, sizeof(mXenInfo));
 
   AsmCpuid (XenLeaf + 2, &TransferPages, &TransferReg, NULL, NULL);
   mXenInfo.HyperPages = AllocatePages (TransferPages);
@@ -72,6 +78,31 @@ XenConnect (
   /* TBD: Locate hvm_info and reserve it away. */
   mXenInfo.HvmInfo = NULL;
 
+  if (!AsciiStrCmp ((CHAR8 *) Info->Signature, "XenHVMOVMF")) {
+    struct e820_entry *E820Map;
+    UINTN Loop, EntryCount, Base;
+
+    /* E820 map */
+    EntryCount = Info->E820Nr;
+    Base = Info->E820;
+
+    E820Map = AllocateZeroPool (sizeof(struct e820_entry) * EntryCount);
+
+    if (!E820Map) {
+      FreePages (mXenInfo.HyperPages, TransferPages);
+      return EFI_OUT_OF_RESOURCES;
+    }
+
+    for (Loop = 0; Loop < EntryCount; Loop++) {
+      struct e820_entry *src = (struct e820_entry *)Base + Loop;
+      struct e820_entry *dst = (struct e820_entry *)E820Map + Loop;
+      CopyMem (dst, src, sizeof(struct e820_entry));
+    }
+
+    mXenInfo.E820 = E820Map;
+    mXenInfo.E820EntryCount = EntryCount;
+  }
+
   BuildGuidDataHob (
     &gEfiXenInfoGuid,
     &mXenInfo,
-- 
1.7.10.4