forked from luck/tmp_suning_uos_patched
7d35b8d09f
This patch adds cpu hotplug support for OMAP4430. Only CPU inactive state is supported as a low power state in the basic hot-plug support Signed-off-by: Rajendra Nayak <rnayak@ti.com> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Cc: Kevin Hilman <khilman@deeprootsystems.com> Signed-off-by: Tony Lindgren <tony@atomide.com>
80 lines
1.7 KiB
C
80 lines
1.7 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 <linux/completion.h>
|
|
|
|
#include <asm/cacheflush.h>
|
|
#include <mach/omap4-common.h>
|
|
|
|
static DECLARE_COMPLETION(cpu_killed);
|
|
|
|
int platform_cpu_kill(unsigned int cpu)
|
|
{
|
|
return wait_for_completion_timeout(&cpu_killed, 5000);
|
|
}
|
|
|
|
/*
|
|
* platform-specific code to shutdown a CPU
|
|
* Called with IRQs disabled
|
|
*/
|
|
void platform_cpu_die(unsigned int cpu)
|
|
{
|
|
unsigned int this_cpu = hard_smp_processor_id();
|
|
|
|
if (cpu != this_cpu) {
|
|
pr_crit("platform_cpu_die running on %u, should be %u\n",
|
|
this_cpu, cpu);
|
|
BUG();
|
|
}
|
|
pr_notice("CPU%u: shutdown\n", cpu);
|
|
complete(&cpu_killed);
|
|
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;
|
|
}
|