updated the Bus Driver that is able to create all or one of its child handles on each call to Start() not to create new child handle if RemainingDeviepath is the End of Device Path Node, per UEFI 2.3.

The others changes include:
1. Check RemainingDevicePath at beginning of Supported(), make sure it has been verified before Start() is called.
2. Check IO protocol firstly rather than EfiDevicePathProtocolGuid, reduce the times entering into Start() function because EfiDevicePathProtocolGuid existed on most of handle.
3. If no any child device is created on last time, and RemainingDevicePath is valid Uart Devcie path, go on creating child device handle based on this RemainingDevicePath.


git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@9262 6f19259b-4bc3-4df7-8a09-765794883524

1 files changed, 55 insertions, 29 deletions

diff --git a/Nt32Pkg/WinNtBusDriverDxe/WinNtBusDriver.c b/Nt32Pkg/WinNtBusDriverDxe/WinNtBusDriver.c
index 86d7929..c2e76c3 100644
--- a/Nt32Pkg/WinNtBusDriverDxe/WinNtBusDriver.c
+++ b/Nt32Pkg/WinNtBusDriverDxe/WinNtBusDriver.c
@@ -1,6 +1,6 @@
 /**@file

 

-Copyright (c) 2006 - 2007, Intel Corporation

+Copyright (c) 2006 - 2009, Intel Corporation

 All rights reserved. This program and the accompanying materials

 are licensed and made available under the terms and conditions of the BSD License

 which accompanies this distribution.  The full text of the license may be found at

@@ -239,20 +239,30 @@ Returns:
   // it is a legal Device Path Node for this bus driver's children.

   //

   if (RemainingDevicePath != NULL) {

-    if (RemainingDevicePath->Type != HARDWARE_DEVICE_PATH ||

-        RemainingDevicePath->SubType != HW_VENDOR_DP ||

-        DevicePathNodeLength(RemainingDevicePath) != sizeof(WIN_NT_VENDOR_DEVICE_PATH_NODE)) {

-      return EFI_UNSUPPORTED;

-    }

-

-    for (Index = 0; Index < NT_PCD_ARRAY_SIZE; Index++) {

-      if (CompareGuid (&((VENDOR_DEVICE_PATH *) RemainingDevicePath)->Guid, mPcdEnvironment[Index].DevicePathGuid)) {

-        break;

+    //

+    // Check if RemainingDevicePath is the End of Device Path Node, 

+    // if yes, go on checking other conditions

+    //

+    if (!IsDevicePathEnd (RemainingDevicePath)) {

+      //

+      // If RemainingDevicePath isn't the End of Device Path Node,

+      // check its validation

+      //

+      if (RemainingDevicePath->Type != HARDWARE_DEVICE_PATH ||

+          RemainingDevicePath->SubType != HW_VENDOR_DP ||

+          DevicePathNodeLength(RemainingDevicePath) != sizeof(WIN_NT_VENDOR_DEVICE_PATH_NODE)) {

+        return EFI_UNSUPPORTED;

+      }

+  

+      for (Index = 0; Index < NT_PCD_ARRAY_SIZE; Index++) {

+        if (CompareGuid (&((VENDOR_DEVICE_PATH *) RemainingDevicePath)->Guid, mPcdEnvironment[Index].DevicePathGuid)) {

+          break;

+        }

+      }

+  

+      if (Index >= NT_PCD_ARRAY_SIZE) {

+        return EFI_UNSUPPORTED;

       }

-    }

-

-    if (Index >= NT_PCD_ARRAY_SIZE) {

-      return EFI_UNSUPPORTED;

     }

   }

 

@@ -261,8 +271,8 @@ Returns:
   //

   Status = gBS->OpenProtocol (

                   ControllerHandle,

-                  &gEfiDevicePathProtocolGuid,

-                  (VOID **) &ParentDevicePath,

+                  &gEfiWinNtThunkProtocolGuid,

+                  (VOID **) &WinNtThunk,

                   This->DriverBindingHandle,

                   ControllerHandle,

                   EFI_OPEN_PROTOCOL_BY_DRIVER

@@ -275,17 +285,23 @@ Returns:
     return Status;

   }

 

+  //

+  // Close the I/O Abstraction(s) used to perform the supported test

+  //

   gBS->CloseProtocol (

         ControllerHandle,

-        &gEfiDevicePathProtocolGuid,

+        &gEfiWinNtThunkProtocolGuid,

         This->DriverBindingHandle,

         ControllerHandle

         );

 

+  //

+  // Open the EFI Device Path protocol needed to perform the supported test

+  //

   Status = gBS->OpenProtocol (

                   ControllerHandle,

-                  &gEfiWinNtThunkProtocolGuid,

-                  (VOID **) &WinNtThunk,

+                  &gEfiDevicePathProtocolGuid,

+                  (VOID **) &ParentDevicePath,

                   This->DriverBindingHandle,

                   ControllerHandle,

                   EFI_OPEN_PROTOCOL_BY_DRIVER

@@ -307,11 +323,11 @@ Returns:
   }

 

   //

-  // Close the I/O Abstraction(s) used to perform the supported test

+  // Close protocol, don't use device path protocol in the Support() function

   //

   gBS->CloseProtocol (

         ControllerHandle,

-        &gEfiWinNtThunkProtocolGuid,

+        &gEfiDevicePathProtocolGuid,

         This->DriverBindingHandle,

         ControllerHandle

         );

@@ -470,15 +486,25 @@ Returns:
       CreateDevice = TRUE;

       if (RemainingDevicePath != NULL) {

         CreateDevice  = FALSE;

-        Node          = (WIN_NT_VENDOR_DEVICE_PATH_NODE *) RemainingDevicePath;

-        if (Node->VendorDevicePath.Header.Type == HARDWARE_DEVICE_PATH &&

-            Node->VendorDevicePath.Header.SubType == HW_VENDOR_DP &&

-            DevicePathNodeLength (&Node->VendorDevicePath.Header) == sizeof (WIN_NT_VENDOR_DEVICE_PATH_NODE)

-            ) {

-          if (CompareGuid (&Node->VendorDevicePath.Guid, mPcdEnvironment[Index].DevicePathGuid) &&

-              Node->Instance == Count

+        //

+        // Check if RemainingDevicePath is the End of Device Path Node, 

+        // if yes, don't create any child device 

+        //

+        if (!IsDevicePathEnd (RemainingDevicePath)) {

+          //

+          // If RemainingDevicePath isn't the End of Device Path Node,

+          // check its validation

+          //

+          Node          = (WIN_NT_VENDOR_DEVICE_PATH_NODE *) RemainingDevicePath;

+          if (Node->VendorDevicePath.Header.Type == HARDWARE_DEVICE_PATH &&

+              Node->VendorDevicePath.Header.SubType == HW_VENDOR_DP &&

+              DevicePathNodeLength (&Node->VendorDevicePath.Header) == sizeof (WIN_NT_VENDOR_DEVICE_PATH_NODE)

               ) {

-            CreateDevice = TRUE;

+            if (CompareGuid (&Node->VendorDevicePath.Guid, mPcdEnvironment[Index].DevicePathGuid) &&

+                Node->Instance == Count

+                ) {

+              CreateDevice = TRUE;

+            }

           }

         }

       }