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/MdePkg/Include/Ppi/Stall.h b/uefi/linaro-edk2/MdePkg/Include/Ppi/Stall.h
new file mode 100644
index 0000000..ebd93d6
--- /dev/null
+++ b/uefi/linaro-edk2/MdePkg/Include/Ppi/Stall.h
@@ -0,0 +1,62 @@
+/** @file

+  This file declares Stall PPI.

+

+  This ppi abstracts the blocking stall service to other agents.

+

+  Copyright (c) 2006 - 2008, 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.             

+

+  @par Revision Reference:

+  This PPI is introduced in PI Version 1.0.

+

+**/

+

+#ifndef __STALL_PPI_H__

+#define __STALL_PPI_H__

+

+#define EFI_PEI_STALL_PPI_GUID \

+  { 0x1f4c6f90, 0xb06b, 0x48d8, {0xa2, 0x01, 0xba, 0xe5, 0xf1, 0xcd, 0x7d, 0x56 } }

+

+typedef struct _EFI_PEI_STALL_PPI EFI_PEI_STALL_PPI;

+

+/**

+  The Stall() function provides a blocking stall for at least the number 

+  of microseconds stipulated in the final argument of the API.

+

+  @param  PeiServices    An indirect pointer to the PEI Services Table

+                         published by the PEI Foundation.

+  @param  This           Pointer to the local data for the interface.

+  @param  Microseconds   Number of microseconds for which to stall.

+

+  @retval EFI_SUCCESS    The service provided at least the required delay.

+

+**/

+typedef

+EFI_STATUS

+(EFIAPI *EFI_PEI_STALL)(

+  IN CONST EFI_PEI_SERVICES     **PeiServices,

+  IN CONST EFI_PEI_STALL_PPI    *This,

+  IN UINTN                      Microseconds

+  );

+

+///

+/// This service provides a simple, blocking stall with platform-specific resolution. 

+///

+struct _EFI_PEI_STALL_PPI {

+  ///

+  /// The resolution in microseconds of the stall services.

+  ///

+  UINTN          Resolution;

+

+  EFI_PEI_STALL  Stall;

+};

+

+extern EFI_GUID gEfiPeiStallPpiGuid;

+

+#endif