mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-22 10:31:08 +00:00
b5b4f2881f
Program non-boot CPUs to hit lowest supported power state when it is off-lined using cpu hotplug framework. Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Jean Pihet <j-pihet@ti.com> Reviewed-by: Kevin Hilman <khilman@ti.com> Tested-by: Vishwanath BS <vishwanath.bs@ti.com> Signed-off-by: Kevin Hilman <khilman@ti.com>
72 lines
1.5 KiB
C
72 lines
1.5 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 "common.h"
|
|
|
|
#include "powerdomain.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)
|
|
{
|
|
unsigned int this_cpu;
|
|
|
|
flush_cache_all();
|
|
dsb();
|
|
|
|
/*
|
|
* we're ready for shutdown now, so do it
|
|
*/
|
|
if (omap_modify_auxcoreboot0(0x0, 0x200) != 0x0)
|
|
pr_err("Secure clear status failed\n");
|
|
|
|
for (;;) {
|
|
/*
|
|
* Enter into low power state
|
|
*/
|
|
omap4_hotplug_cpu(cpu, PWRDM_POWER_OFF);
|
|
this_cpu = smp_processor_id();
|
|
if (omap_read_auxcoreboot0() == this_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;
|
|
}
|