audk/ArmVirtPkg/Library/XenVirtMemInfoLib/AArch64/PhysAddrTop.S

40 lines
1.1 KiB
ArmAsm

#
# Copyright (c) 2011-2013, ARM Limited. All rights reserved.
# Copyright (c) 2016-2017, Linaro 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>
//EFI_PHYSICAL_ADDRESS
//GetPhysAddrTop (
// VOID
// );
ASM_FUNC(ArmGetPhysAddrTop)
mrs x0, id_aa64mmfr0_el1
adr x1, .LPARanges
and x0, x0, #7
ldrb w1, [x1, x0]
mov x0, #1
lsl x0, x0, x1
ret
//
// Bits 0..2 of the AA64MFR0_EL1 system register encode the size of the
// physical address space support on this CPU:
// 0 == 32 bits, 1 == 36 bits, etc etc
// 6 and 7 are reserved
//
.LPARanges:
.byte 32, 36, 40, 42, 44, 48, -1, -1
ASM_FUNCTION_REMOVE_IF_UNREFERENCED