3 files changed, 41 insertions, 0 deletions
diff --git a/OvmfPkg/Library/PlatformBdsLib/BdsPlatform.c b/OvmfPkg/Library/PlatformBdsLib/BdsPlatform.c
index de13c6b5c3..ce299875cd 100644
--- a/OvmfPkg/Library/PlatformBdsLib/BdsPlatform.c
+++ b/OvmfPkg/Library/PlatformBdsLib/BdsPlatform.c
@@ -1163,6 +1163,27 @@ Returns:
 }
 
 
+/**
+  Empty callback function executed when the EndOfDxe event group is signaled.
+
+  We only need this function because we'd like to signal EndOfDxe, and for that
+  we need to create an event, with a callback function.
+
+  @param[in] Event    Event whose notification function is being invoked.
+  @param[in] Context  The pointer to the notification function's context, which
+                      is implementation-dependent.
+**/
+STATIC
+VOID
+EFIAPI
+OnEndOfDxe (
+  IN EFI_EVENT Event,
+  IN VOID      *Context
+  )
+{
+}
+
+
 VOID
 EFIAPI
 PlatformBdsPolicyBehavior (
@@ -1197,12 +1218,28 @@ Returns:
 {
   EFI_STATUS                         Status;
   EFI_BOOT_MODE                      BootMode;
+  EFI_EVENT                          EndOfDxeEvent;
 
   DEBUG ((EFI_D_INFO, "PlatformBdsPolicyBehavior\n"));
 
   VisitAllInstancesOfProtocol (&gEfiPciRootBridgeIoProtocolGuid,
     ConnectRootBridge, NULL);
 
+  //
+  // We can't signal End-of-Dxe earlier than this. Namely, End-of-Dxe triggers
+  // the preparation of S3 system information. That logic has a hard dependency
+  // on the presence of the FACS ACPI table. Since our ACPI tables are only
+  // installed after PCI enumeration completes, we must not trigger the S3 save
+  // earlier, hence we can't signal End-of-Dxe earlier.
+  //
+  Status = gBS->CreateEventEx (EVT_NOTIFY_SIGNAL, TPL_CALLBACK, OnEndOfDxe,
+                  NULL /* NotifyContext */, &gEfiEndOfDxeEventGroupGuid,
+                  &EndOfDxeEvent);
+  if (!EFI_ERROR (Status)) {
+    gBS->SignalEvent (EndOfDxeEvent);
+    gBS->CloseEvent (EndOfDxeEvent);
+  }
+
   if (PcdGetBool (PcdOvmfFlashVariablesEnable)) {
     DEBUG ((EFI_D_INFO, "PlatformBdsPolicyBehavior: not restoring NvVars "
       "from disk since flash variables appear to be supported.\n"));
diff --git a/OvmfPkg/Library/PlatformBdsLib/BdsPlatform.h b/OvmfPkg/Library/PlatformBdsLib/BdsPlatform.h
index e3e950e4ae..b510178668 100644
--- a/OvmfPkg/Library/PlatformBdsLib/BdsPlatform.h
+++ b/OvmfPkg/Library/PlatformBdsLib/BdsPlatform.h
@@ -59,6 +59,7 @@ Abstract:
 #include <Guid/Mps.h>
 #include <Guid/HobList.h>
 #include <Guid/GlobalVariable.h>
+#include <Guid/EventGroup.h>
 
 #include <OvmfPlatforms.h>
 
diff --git a/OvmfPkg/Library/PlatformBdsLib/PlatformBdsLib.inf b/OvmfPkg/Library/PlatformBdsLib/PlatformBdsLib.inf
index ce2972013d..c40871b673 100644
--- a/OvmfPkg/Library/PlatformBdsLib/PlatformBdsLib.inf
+++ b/OvmfPkg/Library/PlatformBdsLib/PlatformBdsLib.inf
@@ -65,3 +65,6 @@
 [Protocols]
   gEfiDecompressProtocolGuid
   gEfiPciRootBridgeIoProtocolGuid
+
+[Guids]
+  gEfiEndOfDxeEventGroupGuid