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/*
* Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
*
* 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; either version 2 of the License, or
* (at your option) any later version.
* 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 Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/smp.h>
#include <mach/hardware.h>
#include <asm/mach-types.h>
#include <linux/io.h>
#include "src-reg.h"
#include <linux/sched.h>
#include <asm/cacheflush.h>
static atomic_t cpu_die_done = ATOMIC_INIT(0);
int platform_cpu_kill(unsigned int cpu)
{
void __iomem *src_base = IO_ADDRESS(SRC_BASE_ADDR);
unsigned int val;
val = jiffies;
/* wait secondary cpu to die, timeout is 50ms */
while (atomic_read(&cpu_die_done) == 0) {
if (time_after(jiffies, (unsigned long)(val + HZ / 20))) {
printk(KERN_WARNING "cpu %d: cpu could not die\n", cpu);
break;
}
}
/*
* we're ready for shutdown now, so do it
*/
val = __raw_readl(src_base + SRC_SCR_OFFSET);
val &= ~(1 << (BP_SRC_SCR_CORES_DBG_RST + cpu));
val |= (1 << (BP_SRC_SCR_CORE0_RST + cpu));
__raw_writel(val, src_base + SRC_SCR_OFFSET);
val = jiffies;
/* wait secondary cpu reset done, timeout is 10ms */
while ((__raw_readl(src_base + SRC_SCR_OFFSET) &
(1 << (BP_SRC_SCR_CORE0_RST + cpu))) != 0) {
if (time_after(jiffies, (unsigned long)(val + HZ / 100))) {
printk(KERN_WARNING "cpu %d: cpu reset fail\n", cpu);
break;
}
}
atomic_set(&cpu_die_done, 0);
return 1;
}
/*
* platform-specific code to shutdown a CPU
* Called with IRQs disabled
*/
void platform_cpu_die(unsigned int cpu)
{
if (cpu == 0) {
printk(KERN_ERR "CPU0 can't be disabled!\n");
return;
}
flush_cache_all();
dsb();
/* tell cpu0 to kill me */
atomic_set(&cpu_die_done, 1);
for (;;) {
/*
* Execute WFI
*/
cpu_do_idle();
}
}
int platform_cpu_disable(unsigned int cpu)
{
/*
* we don't allow CPU 0 to be shutdown (it is still too special
* e.g. clock tick interrupts)
*/
return cpu == 0 ? -EPERM : 0;
}
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