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#
# Copyright (c) 2011-2012, 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 <AsmMacroIoLib.h>
#include <Base.h>
#include <Library/PcdLib.h>
#include <AutoGen.h>
#.include AsmMacroIoLib.inc
#include <Chipset/ArmCortexA9.h>
.text
.align 2
GCC_ASM_EXPORT(ArmGetCpuCountPerCluster)
# IN None
# OUT r0 = SCU Base Address
ASM_PFX(ArmGetScuBaseAddress):
# Read Configuration Base Address Register. ArmCBar cannot be called to get
# the Configuration BAR as a stack is not necessary setup. The SCU is at the
# offset 0x0000 from the Private Memory Region.
mrc p15, 4, r0, c15, c0, 0
bx lr
# IN None
# OUT r0 = number of cores present in the system
ASM_PFX(ArmGetCpuCountPerCluster):
stmfd SP!, {r1-r2}
# Read CP15 MIDR
mrc p15, 0, r1, c0, c0, 0
# Check if the CPU is A15
mov r1, r1, LSR #4
LoadConstantToReg (ARM_CPU_TYPE_MASK, r0)
and r1, r1, r0
LoadConstantToReg (ARM_CPU_TYPE_A15, r0)
cmp r1, r0
beq _Read_cp15_reg
_CPU_is_not_A15:
mov r2, lr @ Save link register
bl ArmGetScuBaseAddress @ Read SCU Base Address
mov lr, r2 @ Restore link register val
ldr r0, [r0, #A9_SCU_CONFIG_OFFSET] @ Read SCU Config reg to get CPU count
b _Return
_Read_cp15_reg:
mrc p15, 1, r0, c9, c0, 2 @ Read C9 register of CP15 to get CPU count
lsr r0, #24
_Return:
and r0, r0, #3
# Add '1' to the number of CPU on the Cluster
add r0, r0, #1
ldmfd SP!, {r1-r2}
bx lr
ASM_FUNCTION_REMOVE_IF_UNREFERENCED
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