linux/arch/arm/mach-shmobile/smp-r8a7791.c

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/*
* SMP support for r8a7791
*
* Copyright (C) 2013 Renesas Solutions Corp.
* Copyright (C) 2013 Magnus Damm
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/io.h>
#include <asm/smp_plat.h>
#include <mach/r8a7791.h>
#include <mach/rcar-gen2.h>
#include "common.h"
#define RST 0xe6160000
#define CA15BAR 0x0020
#define CA15RESCNT 0x0040
#define RAM 0xe6300000
static void __init r8a7791_smp_prepare_cpus(unsigned int max_cpus)
{
void __iomem *p;
u32 bar;
/* let APMU code install data related to shmobile_boot_vector */
shmobile_smp_apmu_prepare_cpus(max_cpus);
/* RAM for jump stub, because BAR requires 256KB aligned address */
p = ioremap_nocache(RAM, shmobile_boot_size);
memcpy_toio(p, shmobile_boot_vector, shmobile_boot_size);
iounmap(p);
/* setup reset vectors */
p = ioremap_nocache(RST, 0x63);
bar = (RAM >> 8) & 0xfffffc00;
writel_relaxed(bar, p + CA15BAR);
writel_relaxed(bar | 0x10, p + CA15BAR);
/* enable clocks to all CPUs */
writel_relaxed((readl_relaxed(p + CA15RESCNT) & ~0x0f) | 0xa5a50000,
p + CA15RESCNT);
iounmap(p);
}
static int r8a7791_smp_boot_secondary(unsigned int cpu,
struct task_struct *idle)
{
/* Error out when hardware debug mode is enabled */
if (rcar_gen2_read_mode_pins() & BIT(21)) {
pr_warn("Unable to boot CPU%u when MD21 is set\n", cpu);
return -ENOTSUPP;
}
return shmobile_smp_apmu_boot_secondary(cpu, idle);
}
struct smp_operations r8a7791_smp_ops __initdata = {
.smp_prepare_cpus = r8a7791_smp_prepare_cpus,
.smp_boot_secondary = r8a7791_smp_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_disable = shmobile_smp_cpu_disable,
.cpu_die = shmobile_smp_apmu_cpu_die,
.cpu_kill = shmobile_smp_apmu_cpu_kill,
#endif
};