M7350/kernel/arch/arm/mach-msm/hotplug.c
2024-09-09 08:57:42 +00:00

148 lines
3.3 KiB
C

/*
* Copyright (C) 2002 ARM Ltd.
* All Rights Reserved
* Copyright (c) 2011-2014, 2016 The Linux Foundation. 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 version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/smp.h>
#include <linux/cpu.h>
#include <linux/notifier.h>
#include <soc/qcom/spm.h>
#include <soc/qcom/pm.h>
#include <linux/irqchip/arm-gic.h>
#include <asm/smp_plat.h>
#include <asm/vfp.h>
#include <soc/qcom/jtag.h>
static cpumask_t cpu_dying_mask;
static DEFINE_PER_CPU(unsigned int, warm_boot_flag);
static inline void cpu_enter_lowpower(void)
{
}
static inline void cpu_leave_lowpower(void)
{
}
static inline void platform_do_lowpower(unsigned int cpu, int *spurious)
{
/* Just enter wfi for now. TODO: Properly shut off the cpu. */
for (;;) {
lpm_cpu_hotplug_enter(cpu);
if (pen_release == cpu_logical_map(cpu)) {
/*
* OK, proper wakeup, we're done
*/
break;
}
/*
* getting here, means that we have come out of WFI without
* having been woken up - this shouldn't happen
*
* The trouble is, letting people know about this is not really
* possible, since we are currently running incoherently, and
* therefore cannot safely call printk() or anything else
* Read the pending interrupts to understand why we woke up
*/
#ifdef CONFIG_MSM_PM
gic_show_pending_irq();
#endif
(*spurious)++;
}
}
int msm_cpu_kill(unsigned int cpu)
{
int ret = 0;
if (cpumask_test_and_clear_cpu(cpu, &cpu_dying_mask))
ret = msm_pm_wait_cpu_shutdown(cpu);
return ret ? 0 : 1;
}
/*
* platform-specific code to shutdown a CPU
*
* Called with IRQs disabled
*/
void __ref msm_cpu_die(unsigned int cpu)
{
int spurious = 0;
if (unlikely(cpu != smp_processor_id())) {
pr_crit("%s: running on %u, should be %u\n",
__func__, smp_processor_id(), cpu);
BUG();
}
/*
* we're ready for shutdown now, so do it
*/
cpu_enter_lowpower();
platform_do_lowpower(cpu, &spurious);
pr_debug("CPU%u: %s: normal wakeup\n", cpu, __func__);
cpu_leave_lowpower();
if (spurious)
pr_warn("CPU%u: %u spurious wakeup calls\n", cpu, spurious);
}
static int hotplug_dying_callback(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
switch (action & (~CPU_TASKS_FROZEN)) {
case CPU_DYING:
cpumask_set_cpu((unsigned long)hcpu, &cpu_dying_mask);
break;
default:
break;
}
return NOTIFY_OK;
}
static struct notifier_block hotplug_dying_notifier = {
.notifier_call = hotplug_dying_callback,
};
int msm_platform_secondary_init(unsigned int cpu)
{
int ret;
unsigned int *warm_boot = &__get_cpu_var(warm_boot_flag);
if (!(*warm_boot)) {
*warm_boot = 1;
/*
* All CPU0 boots are considered warm boots (restore needed)
* since CPU0 is the system boot CPU and never cold-booted
* by the kernel.
*/
if (cpu)
return 0;
}
msm_jtag_restore_state();
#if defined(CONFIG_VFP) && defined (CONFIG_CPU_PM)
vfp_pm_resume();
#endif
ret = msm_spm_set_low_power_mode(MSM_SPM_MODE_CLOCK_GATING, false);
return ret;
}
static int __init init_hotplug_dying(void)
{
return register_hotcpu_notifier(&hotplug_dying_notifier);
}
early_initcall(init_hotplug_dying);