ArmPlatformPkg: Added Aarch64 support

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Harry Liebel <Harry.Liebel@arm.com>
Signed-off-by: Olivier Martin <olivier.martin@arm.com>



git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14489 6f19259b-4bc3-4df7-8a09-765794883524

ArmPlatformPkg/PrePeiCore/AArch64/Helper.S

@@ -0,0 +1,51 @@
+#========================================================================================
+#  Copyright (c) 2011-2013, ARM Limited. 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
+#  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 <AsmMacroIoLibV8.h>
+#include <Chipset/AArch64.h>
+
+#start of the code section
+.text
+.align 3
+
+ASM_GLOBAL ASM_PFX(SetupExceptionLevel1)
+ASM_GLOBAL ASM_PFX(SetupExceptionLevel2)
+
+// Setup EL1 while in EL1
+ASM_PFX(SetupExceptionLevel1):
+   mov  x5, x30                   // Save LR
+
+   mov  x0, #CPACR_CP_FULL_ACCESS
+   bl   ASM_PFX(ArmWriteCpacr)    // Disable copro traps to EL1
+
+   ret  x5
+
+// Setup EL2 while in EL2
+ASM_PFX(SetupExceptionLevel2):
+   msr     sctlr_el2, xzr
+   mrs     x0, hcr_el2            // Read EL2 Hypervisor configuration Register
+
+   // Send all interrupts to their respective Exception levels for EL2
+   orr     x0, x0, #(1 << 3)      // Enable EL2 FIQ
+   orr     x0, x0, #(1 << 4)      // Enable EL2 IRQ
+   orr     x0, x0, #(1 << 5)      // Enable EL2 SError and Abort
+   msr     hcr_el2, x0            // Write back our settings
+
+   msr     cptr_el2, xzr          // Disable copro traps to EL2
+
+   ret
+
+dead:
+   b       dead
+
+ASM_FUNCTION_REMOVE_IF_UNREFERENCED