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linux/arch/arm/mach-omap2/omap-hotplug.c
Russell King bbc81fd432 ARM: CPU hotplug: remove bug checks in platform_cpu_die()
platform_cpu_die() is entered from the CPU's own idle thread, which
can not be migrated to other CPUs.  Moreover, the 'cpu' argument
comes from the thread info, which will always be the 'current'
CPU.  So remove this useless bug check.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-12-20 15:09:10 +00:00

68 lines
1.3 KiB
C

/*
* OMAP4 SMP cpu-hotplug support
*
* Copyright (C) 2010 Texas Instruments, Inc.
* Author:
* Santosh Shilimkar <santosh.shilimkar@ti.com>
*
* Platform file needed for the OMAP4 SMP. This file is based on arm
* realview smp platform.
* Copyright (c) 2002 ARM Limited.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/smp.h>
#include <asm/cacheflush.h>
#include <mach/omap4-common.h>
int platform_cpu_kill(unsigned int cpu)
{
return 1;
}
/*
* platform-specific code to shutdown a CPU
* Called with IRQs disabled
*/
void platform_cpu_die(unsigned int cpu)
{
flush_cache_all();
dsb();
/*
* we're ready for shutdown now, so do it
*/
if (omap_modify_auxcoreboot0(0x0, 0x200) != 0x0)
printk(KERN_CRIT "Secure clear status failed\n");
for (;;) {
/*
* Execute WFI
*/
do_wfi();
if (omap_read_auxcoreboot0() == cpu) {
/*
* OK, proper wakeup, we're done
*/
break;
}
pr_debug("CPU%u: spurious wakeup call\n", cpu);
}
}
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;
}