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linux-next/arch/arm/mach-shmobile/smp-r8a7779.c
Magnus Damm fd0865c3f7 ARM: shmobile: Rearrange r8a7779 cpu hotplug code
Update the r8a7779 SMP code and CPU Hotplug in particular
to follow the same style as sh73a0. This means dropping
__maybe_unused for #ifdef CONFIG_HOTPLUG_CPU.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
2013-03-13 02:13:21 +09:00

192 lines
4.6 KiB
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 <linux/irqchip/arm-gic.h>
#include <mach/common.h>
#include <mach/r8a7779.h>
#include <asm/cacheflush.h>
#include <asm/smp_plat.h>
#include <asm/smp_scu.h>
#include <asm/smp_twd.h>
#define AVECR IOMEM(0xfe700040)
#define R8A7779_SCU_BASE 0xf0000000
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,
};
#ifdef CONFIG_HAVE_ARM_TWD
static DEFINE_TWD_LOCAL_TIMER(twd_local_timer, R8A7779_SCU_BASE + 0x600, 29);
void __init r8a7779_register_twd(void)
{
twd_local_timer_register(&twd_local_timer);
}
#endif
static int r8a7779_platform_cpu_kill(unsigned int cpu)
{
struct r8a7779_pm_ch *ch = NULL;
int ret = -EIO;
cpu = cpu_logical_map(cpu);
if (cpu < ARRAY_SIZE(r8a7779_ch_cpu))
ch = r8a7779_ch_cpu[cpu];
if (ch)
ret = r8a7779_sysc_power_down(ch);
return ret ? ret : 1;
}
static void __cpuinit r8a7779_secondary_init(unsigned int cpu)
{
gic_secondary_init(0);
}
static int __cpuinit r8a7779_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
struct r8a7779_pm_ch *ch = NULL;
int ret = -EIO;
cpu = cpu_logical_map(cpu);
if (cpu < ARRAY_SIZE(r8a7779_ch_cpu))
ch = r8a7779_ch_cpu[cpu];
if (ch)
ret = r8a7779_sysc_power_up(ch);
return ret;
}
static void __init r8a7779_smp_prepare_cpus(unsigned int max_cpus)
{
scu_enable(shmobile_scu_base);
/* Map the reset vector (in headsmp-scu.S) */
__raw_writel(__pa(shmobile_secondary_vector_scu), AVECR);
/* enable cache coherency on booting CPU */
scu_power_mode(shmobile_scu_base, SCU_PM_NORMAL);
r8a7779_pm_init();
/* power off secondary CPUs */
r8a7779_platform_cpu_kill(1);
r8a7779_platform_cpu_kill(2);
r8a7779_platform_cpu_kill(3);
}
static void __init r8a7779_smp_init_cpus(void)
{
/* setup r8a7779 specific SCU base */
shmobile_scu_base = IOMEM(R8A7779_SCU_BASE);
shmobile_smp_init_cpus(scu_get_core_count(shmobile_scu_base));
}
#ifdef CONFIG_HOTPLUG_CPU
static int r8a7779_scu_psr_core_disabled(int cpu)
{
unsigned long mask = 3 << (cpu * 8);
if ((__raw_readl(shmobile_scu_base + 8) & mask) == mask)
return 1;
return 0;
}
static int r8a7779_cpu_kill(unsigned int cpu)
{
int k;
/* this function is running on another CPU than the offline target,
* here we need wait for shutdown code in platform_cpu_die() to
* finish before asking SoC-specific code to power off the CPU core.
*/
for (k = 0; k < 1000; k++) {
if (r8a7779_scu_psr_core_disabled(cpu))
return r8a7779_platform_cpu_kill(cpu);
mdelay(1);
}
return 0;
}
static void r8a7779_cpu_die(unsigned int cpu)
{
dsb();
flush_cache_all();
/* disable cache coherency */
scu_power_mode(shmobile_scu_base, SCU_PM_POWEROFF);
/* Endless loop until power off from r8a7779_cpu_kill() */
while (1)
cpu_do_idle();
}
static int r8a7779_cpu_disable(unsigned int cpu)
{
/* only CPU1->3 have power domains, do not allow hotplug of CPU0 */
return cpu == 0 ? -EPERM : 0;
}
#endif /* CONFIG_HOTPLUG_CPU */
struct smp_operations r8a7779_smp_ops __initdata = {
.smp_init_cpus = r8a7779_smp_init_cpus,
.smp_prepare_cpus = r8a7779_smp_prepare_cpus,
.smp_secondary_init = r8a7779_secondary_init,
.smp_boot_secondary = r8a7779_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_kill = r8a7779_cpu_kill,
.cpu_die = r8a7779_cpu_die,
.cpu_disable = r8a7779_cpu_disable,
#endif
};