blob: 6d47e07aec131011806db86aa017f1d2aa9bef54 [file]
#------------------------------------------------------------------------------
#
# Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
# Copyright (c) 2011 - 2016, ARM Limited. All rights reserved.
# Copyright (c) 2016, Linaro Limited. All rights reserved.
#
# SPDX-License-Identifier: BSD-2-Clause-Patent
#
#------------------------------------------------------------------------------
#include <AsmMacroLib.h>
ASM_FUNC(ArmArchLibGetPhysicalAddressBits)
mrs x0, id_aa64mmfr0_el1
adr x1, .LPARanges
and x0, x0, #0xf
ldrb w0, [x1, x0]
ret
//
// Bits 0..3 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
// 7 and up are reserved
//
.LPARanges:
.byte 32, 36, 40, 42, 44, 48, 52, 0
.byte 0, 0, 0, 0, 0, 0, 0, 0
ASM_FUNCTION_REMOVE_IF_UNREFERENCED