linux/arch/arm/mach-shmobile/smp-sh73a0.c
Kuninori Morimoto d6720003c3 ARM / mach-shmobile: sh73a0 SMP TWD boot regression fix
Fix SMP TWD boot regression on sh73a0 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
sh73a0 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 sh73a0 by moving the TWD
registration code from smp_init_cpus() to sys_timer->init() time.

This patch removed shmobile_twd_init() which is no longer needed

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
2012-05-12 22:13:45 +02:00

107 lines
2.7 KiB
C

/*
* SMP support for R-Mobile / SH-Mobile - sh73a0 portion
*
* Copyright (C) 2010 Magnus Damm
* Copyright (C) 2010 Takashi Yoshii
*
* 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 <mach/common.h>
#include <asm/smp_plat.h>
#include <asm/smp_scu.h>
#include <asm/smp_twd.h>
#include <asm/hardware/gic.h>
#define WUPCR IOMEM(0xe6151010)
#define SRESCR IOMEM(0xe6151018)
#define PSTR IOMEM(0xe6151040)
#define SBAR IOMEM(0xe6180020)
#define APARMBAREA IOMEM(0xe6f10020)
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 sh73a0_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 sh73a0_get_core_count(void)
{
void __iomem *scu_base = scu_base_addr();
return scu_get_core_count(scu_base);
}
void __cpuinit sh73a0_secondary_init(unsigned int cpu)
{
gic_secondary_init(0);
}
int __cpuinit sh73a0_boot_secondary(unsigned int cpu)
{
cpu = cpu_logical_map(cpu);
/* enable cache coherency */
modify_scu_cpu_psr(0, 3 << (cpu * 8));
if (((__raw_readl(PSTR) >> (4 * cpu)) & 3) == 3)
__raw_writel(1 << cpu, WUPCR); /* wake up */
else
__raw_writel(1 << cpu, SRESCR); /* reset */
return 0;
}
void __init sh73a0_smp_prepare_cpus(void)
{
int cpu = cpu_logical_map(0);
scu_enable(scu_base_addr());
/* Map the reset vector (in headsmp.S) */
__raw_writel(0, APARMBAREA); /* 4k */
__raw_writel(__pa(shmobile_secondary_vector), SBAR);
/* enable cache coherency on CPU0 */
modify_scu_cpu_psr(0, 3 << (cpu * 8));
}