smp-r8a7779.c

/*
 * SMP support for R-Mobile / SH-Mobile - r8a7779 portion
 *
 * Copyright (C) 2011  Renesas Solutions Corp.
 * Copyright (C) 2011  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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <mach/common.h>
#include <mach/r8a7779.h>
#include <asm/smp_plat.h>
#include <asm/smp_scu.h>
#include <asm/smp_twd.h>
#include <asm/hardware/gic.h>

#define AVECR 0xfe700040

static struct r8a7779_pm_ch r8a7779_ch_cpu1 = {
	.chan_offs = 0x40, /* PWRSR0 .. PWRER0 */
	.chan_bit = 1, /* ARM1 */
	.isr_bit = 1, /* ARM1 */
};

static struct r8a7779_pm_ch r8a7779_ch_cpu2 = {
	.chan_offs = 0x40, /* PWRSR0 .. PWRER0 */
	.chan_bit = 2, /* ARM2 */
	.isr_bit = 2, /* ARM2 */
};

static struct r8a7779_pm_ch r8a7779_ch_cpu3 = {
	.chan_offs = 0x40, /* PWRSR0 .. PWRER0 */
	.chan_bit = 3, /* ARM3 */
	.isr_bit = 3, /* ARM3 */
};

static struct r8a7779_pm_ch *r8a7779_ch_cpu[4] = {
	[1] = &r8a7779_ch_cpu1,
	[2] = &r8a7779_ch_cpu2,
	[3] = &r8a7779_ch_cpu3,
};

static void __iomem *scu_base_addr(void)
{
	return (void __iomem *)0xf0000000;
}

static DEFINE_SPINLOCK(scu_lock);
static unsigned long tmp;

static void modify_scu_cpu_psr(unsigned long set, unsigned long clr)
{
	void __iomem *scu_base = scu_base_addr();

	spin_lock(&scu_lock);
	tmp = __raw_readl(scu_base + 8);
	tmp &= ~clr;
	tmp |= set;
	spin_unlock(&scu_lock);

	/* disable cache coherency after releasing the lock */
	__raw_writel(tmp, scu_base + 8);
}

unsigned int __init r8a7779_get_core_count(void)
{
	void __iomem *scu_base = scu_base_addr();

#ifdef CONFIG_HAVE_ARM_TWD
	/* twd_base needs to be initialized before percpu_timer_setup() */
	twd_base = (void __iomem *)0xf0000600;
#endif

	return scu_get_core_count(scu_base);
}

int r8a7779_platform_cpu_kill(unsigned int cpu)
{
	struct r8a7779_pm_ch *ch = NULL;
	int ret = -EIO;

	cpu = cpu_logical_map(cpu);

	/* disable cache coherency */
	modify_scu_cpu_psr(3 << (cpu * 8), 0);

	if (cpu < ARRAY_SIZE(r8a7779_ch_cpu))
		ch = r8a7779_ch_cpu[cpu];

	if (ch)
		ret = r8a7779_sysc_power_down(ch);

	return ret ? ret : 1;
}

void __cpuinit r8a7779_secondary_init(unsigned int cpu)
{
	gic_secondary_init(0);
}

int __cpuinit r8a7779_boot_secondary(unsigned int cpu)
{
	struct r8a7779_pm_ch *ch = NULL;
	int ret = -EIO;

	cpu = cpu_logical_map(cpu);

	/* enable cache coherency */
	modify_scu_cpu_psr(0, 3 << (cpu * 8));

	if (cpu < ARRAY_SIZE(r8a7779_ch_cpu))
		ch = r8a7779_ch_cpu[cpu];

	if (ch)
		ret = r8a7779_sysc_power_up(ch);

	return ret;
}

void __init r8a7779_smp_prepare_cpus(void)
{
	int cpu = cpu_logical_map(0);

	scu_enable(scu_base_addr());

	/* Map the reset vector (in headsmp.S) */
	__raw_writel(__pa(shmobile_secondary_vector), __io(AVECR));

	/* enable cache coherency on CPU0 */
	modify_scu_cpu_psr(0, 3 << (cpu * 8));

	r8a7779_pm_init();

	/* power off secondary CPUs */
	r8a7779_platform_cpu_kill(1);
	r8a7779_platform_cpu_kill(2);
	r8a7779_platform_cpu_kill(3);
}