hikey: Add UEFI sources for reference

UEFI needs to be built outside Android build system.
Please follow the instructions in README.

The sources correspond to:
https://github.com/96boards/edk2/commit/14eae0c12e71fd33c4c0fc51e4475e8db02566cf
https://github.com/96boards/arm-trusted-firmware/commit/e9b4909dcd75fc4ae7041cfb83d28ab9adb7afdf
https://github.com/96boards/l-loader/commit/6b784ad5c4ab00e2b1c6f53cd5f74054e5d00a78
https://git.linaro.org/uefi/uefi-tools.git/commit/abe618f8ab72034fff1ce46c9c006a2c6bd40a7e

Change-Id: Ieeefdb63e673e0c8e64e0a1f02c7bddc63b2c7fb
Signed-off-by: Vishal Bhoj <vishal.bhoj@linaro.org>
diff --git a/uefi/linaro-edk2/OvmfPkg/VirtioNetDxe/Events.c b/uefi/linaro-edk2/OvmfPkg/VirtioNetDxe/Events.c
new file mode 100644
index 0000000..5be1af6
--- /dev/null
+++ b/uefi/linaro-edk2/OvmfPkg/VirtioNetDxe/Events.c
@@ -0,0 +1,91 @@
+/** @file

+

+  Implements

+  - the SNM.WaitForPacket EVT_NOTIFY_WAIT event,

+  - the EVT_SIGNAL_EXIT_BOOT_SERVICES event

+  for the virtio-net driver.

+

+  Copyright (C) 2013, Red Hat, Inc.

+  Copyright (c) 2006 - 2012, Intel Corporation. All rights reserved.<BR>

+

+  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

+  http://opensource.org/licenses/bsd-license.php

+

+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT

+  WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

+

+**/

+

+#include <Library/BaseLib.h>

+#include <Library/UefiBootServicesTableLib.h>

+

+#include "VirtioNet.h"

+

+/**

+  Invoke a notification event

+

+  @param  Event                 Event whose notification function is being

+                                invoked.

+  @param  Context               The pointer to the notification function's

+                                context, which is implementation-dependent.

+

+**/

+

+VOID

+EFIAPI

+VirtioNetIsPacketAvailable (

+  IN  EFI_EVENT Event,

+  IN  VOID      *Context

+  )

+{

+  //

+  // This callback has been enqueued by an external application and is

+  // running at TPL_CALLBACK already.

+  //

+  // The WaitForPacket logic is similar to that of WaitForKey. The former has

+  // almost no documentation in either the UEFI-2.3.1+errC spec or the

+  // DWG-2.3.1, but WaitForKey does have some.

+  //

+  VNET_DEV *Dev;

+  UINT16   RxCurUsed;

+

+  Dev = Context;

+  if (Dev->Snm.State != EfiSimpleNetworkInitialized) {

+    return;

+  }

+

+  //

+  // virtio-0.9.5, 2.4.2 Receiving Used Buffers From the Device

+  //

+  MemoryFence ();

+  RxCurUsed = *Dev->RxRing.Used.Idx;

+  MemoryFence ();

+

+  if (Dev->RxLastUsed != RxCurUsed) {

+    gBS->SignalEvent (&Dev->Snp.WaitForPacket);

+  }

+}

+

+VOID

+EFIAPI

+VirtioNetExitBoot (

+  IN  EFI_EVENT Event,

+  IN  VOID      *Context

+  )

+{

+  //

+  // This callback has been enqueued by ExitBootServices() and is running at

+  // TPL_CALLBACK already.

+  //

+  // Shut down pending transfers according to DWG-2.3.1, "25.5.1 Exit Boot

+  // Services Event".

+  //

+  VNET_DEV *Dev;

+

+  Dev = Context;

+  if (Dev->Snm.State == EfiSimpleNetworkInitialized) {

+    Dev->VirtIo->SetDeviceStatus (Dev->VirtIo, 0);

+  }

+}