xref: /OK3568_Linux_fs/kernel/arch/arm/mach-shmobile/headsmp-scu.S (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun/* SPDX-License-Identifier: GPL-2.0+
2*4882a593Smuzhiyun *
3*4882a593Smuzhiyun * Shared SCU setup for mach-shmobile
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright (C) 2012 Bastian Hecht
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun#include <linux/linkage.h>
9*4882a593Smuzhiyun#include <linux/init.h>
10*4882a593Smuzhiyun#include <asm/memory.h>
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun/*
13*4882a593Smuzhiyun * Boot code for secondary CPUs.
14*4882a593Smuzhiyun *
15*4882a593Smuzhiyun * First we turn on L1 cache coherency for our CPU. Then we jump to
16*4882a593Smuzhiyun * secondary_startup that invalidates the cache and hands over control
17*4882a593Smuzhiyun * to the common ARM startup code.
18*4882a593Smuzhiyun */
19*4882a593SmuzhiyunENTRY(shmobile_boot_scu)
20*4882a593Smuzhiyun					@ r0 = SCU base address
21*4882a593Smuzhiyun	mrc     p15, 0, r1, c0, c0, 5	@ read MPIDR
22*4882a593Smuzhiyun	and	r1, r1, #3		@ mask out cpu ID
23*4882a593Smuzhiyun	lsl	r1, r1, #3		@ we will shift by cpu_id * 8 bits
24*4882a593Smuzhiyun	ldr	r2, [r0, #8]		@ SCU Power Status Register
25*4882a593Smuzhiyun	mov	r3, #3
26*4882a593Smuzhiyun	lsl	r3, r3, r1
27*4882a593Smuzhiyun	bic	r2, r2, r3		@ Clear bits of our CPU (Run Mode)
28*4882a593Smuzhiyun	str	r2, [r0, #8]		@ write back
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun	b	secondary_startup
31*4882a593SmuzhiyunENDPROC(shmobile_boot_scu)
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