audk/ArmPlatformPkg/PrePeiCore/AArch64/Helper.S

49 lines
1.6 KiB
ArmAsm

#========================================================================================
# 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
GCC_ASM_EXPORT(SetupExceptionLevel1)
GCC_ASM_EXPORT(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
ASM_FUNCTION_REMOVE_IF_UNREFERENCED