linux/arch/arm/mach-shmobile/smp-r8a7779.c
Magnus Damm b759bd114e ARM / mach-shmobile: r8a7779 SMP TWD boot regression fix
Fix SMP TWD boot regression on r8a7779 based platforms caused by:

4200b16 ARM: shmobile: convert to twd_local_timer_register() interface

After the merge of the above commit it has been impossible to boot
r8a7779 based SoCs with SMP enabled and CONFIG_HAVE_ARM_TWD=y. The
kernel crashes at smp_init_cpus() timing which is before the console
has been initialized, so to the user this looks like a kernel lock up
without any particular error message.

This patch fixes the regression on r8a7779 by moving the TWD
registration code from smp_init_cpus() to sys_timer->init() time.

Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-12 22:13:38 +02:00

158 lines
3.6 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 <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 IOMEM(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;
#ifdef CONFIG_HAVE_ARM_TWD
static DEFINE_TWD_LOCAL_TIMER(twd_local_timer, 0xf0000600, 29);
void __init r8a7779_register_twd(void)
{
twd_local_timer_register(&twd_local_timer);
}
#endif
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();
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), 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);
}