Fixed system hang issue with accessing to Boot Maintenance Manager

when pressed hot key to enter BIOS setup.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Shifei Lu <shifeix.a.lu@intel.com>
Reviewed-by: Tim He <tim.he@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16666 6f19259b-4bc3-4df7-8a09-765794883524

Vlv2TbltDevicePkg/Library/PlatformBdsLib/BdsPlatform.c

@@ -2051,7 +2051,11 @@ PlatformBdsEnterFrontPageWithHotKey (
     // Ensure screen is clear when switch Console from Graphics mode to Text mode
     //
     gST->ConOut->EnableCursor (gST->ConOut, TRUE);
-    gST->ConOut->ClearScreen (gST->ConOut);
+    gST->ConOut->ClearScreen (gST->ConOut);
+
+    if (EFI_ERROR (Status)) {
+      //
+      // Timeout or user press enter to continue
       //
       goto Exit;
     }
@@ -2113,11 +2117,20 @@ PlatformBdsEnterFrontPageWithHotKey (
       // User hit continue
       //
       break;
+
+    case FRONT_PAGE_KEY_LANGUAGE:
+
+      //
       // User made a language setting change - display front page again
       //
       break;
 
     case FRONT_PAGE_KEY_BOOT_MANAGER:
+      //
+	  // Remove the installed BootMaint HiiPackages when exit.
+      //
+      FreeBMPackage ();
+
       //
       // User chose to run the Boot Manager
       //
@@ -2145,6 +2158,10 @@ PlatformBdsEnterFrontPageWithHotKey (
       // Display the Boot Maintenance Manager
       //
       BdsStartBootMaint ();
+      break;
+    }
+
+  } while (((UINTN)gCallbackKey) != FRONT_PAGE_KEY_CONTINUE);
 
   //
   //Will leave browser, check any reset required change is applied? if yes, reset system

Vlv2TbltDevicePkg/Library/PlatformBdsLib/BdsPlatform.h

@@ -391,7 +391,20 @@ PlatformBdsEnterFrontPageWithHotKey (
    IN UINT16					   TimeoutDefault
    );
 
- EFI_STATUS
+ EFI_STATUS
+ InitializeFrontPage (
+   IN BOOLEAN						  InitializeHiiData
+   );
+
+ VOID
+ UpdateFrontPageStrings (
+   VOID
+   );
+   
+   
+ EFI_STATUS
+ InitBMPackage  (
+   VOID
    );