xref: /linux/arch/arm/mach-shmobile/headsmp-scu.S (revision 0be3ff0c)
1/* SPDX-License-Identifier: GPL-2.0+
2 *
3 * Shared SCU setup for mach-shmobile
4 *
5 * Copyright (C) 2012 Bastian Hecht
6 */
7
8#include <linux/linkage.h>
9#include <linux/init.h>
10#include <asm/memory.h>
11
12/*
13 * Boot code for secondary CPUs.
14 *
15 * First we turn on L1 cache coherency for our CPU. Then we jump to
16 * secondary_startup that invalidates the cache and hands over control
17 * to the common ARM startup code.
18 */
19ENTRY(shmobile_boot_scu)
20					@ r0 = SCU base address
21	mrc     p15, 0, r1, c0, c0, 5	@ read MPIDR
22	and	r1, r1, #3		@ mask out cpu ID
23	lsl	r1, r1, #3		@ we will shift by cpu_id * 8 bits
24	ldr	r2, [r0, #8]		@ SCU Power Status Register
25	mov	r3, #3
26	lsl	r3, r3, r1
27	bic	r2, r2, r3		@ Clear bits of our CPU (Run Mode)
28	str	r2, [r0, #8]		@ write back
29
30	b	secondary_startup
31ENDPROC(shmobile_boot_scu)
32