657ebf7a23
Install the callbacks via the state machine so the old notifier based cpuhotplug infrastructure can be removed. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: linux-sh@vger.kernel.org Cc: Peter Zijlstra <peterz@infradead.org> Cc: Magnus Damm <magnus.damm@gmail.com> Cc: Simon Horman <horms@verge.net.au> Cc: rt@linutronix.de Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/20160906170457.32393-3-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
94 lines
2.3 KiB
C
94 lines
2.3 KiB
C
/*
|
|
* SMP support for SoCs with SCU covered by mach-shmobile
|
|
*
|
|
* Copyright (C) 2013 Magnus Damm
|
|
*
|
|
* 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/cpu.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/init.h>
|
|
#include <linux/io.h>
|
|
#include <linux/smp.h>
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/smp_plat.h>
|
|
#include <asm/smp_scu.h>
|
|
#include "common.h"
|
|
|
|
|
|
static phys_addr_t shmobile_scu_base_phys;
|
|
static void __iomem *shmobile_scu_base;
|
|
|
|
static int shmobile_scu_cpu_prepare(unsigned int cpu)
|
|
{
|
|
/* For this particular CPU register SCU SMP boot vector */
|
|
shmobile_smp_hook(cpu, virt_to_phys(shmobile_boot_scu),
|
|
shmobile_scu_base_phys);
|
|
return 0;
|
|
}
|
|
|
|
void __init shmobile_smp_scu_prepare_cpus(phys_addr_t scu_base_phys,
|
|
unsigned int max_cpus)
|
|
{
|
|
/* install boot code shared by all CPUs */
|
|
shmobile_boot_fn = virt_to_phys(shmobile_smp_boot);
|
|
|
|
/* enable SCU and cache coherency on booting CPU */
|
|
shmobile_scu_base_phys = scu_base_phys;
|
|
shmobile_scu_base = ioremap(scu_base_phys, PAGE_SIZE);
|
|
scu_enable(shmobile_scu_base);
|
|
scu_power_mode(shmobile_scu_base, SCU_PM_NORMAL);
|
|
|
|
/* Use CPU notifier for reset vector control */
|
|
cpuhp_setup_state_nocalls(CPUHP_ARM_SHMOBILE_SCU_PREPARE,
|
|
"arm/shmobile-scu:prepare",
|
|
shmobile_scu_cpu_prepare, NULL);
|
|
}
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
void shmobile_smp_scu_cpu_die(unsigned int cpu)
|
|
{
|
|
/* For this particular CPU deregister boot vector */
|
|
shmobile_smp_hook(cpu, 0, 0);
|
|
|
|
dsb();
|
|
flush_cache_all();
|
|
|
|
/* disable cache coherency */
|
|
scu_power_mode(shmobile_scu_base, SCU_PM_POWEROFF);
|
|
|
|
/* jump to shared mach-shmobile sleep / reset code */
|
|
shmobile_smp_sleep();
|
|
}
|
|
|
|
static int shmobile_smp_scu_psr_core_disabled(int cpu)
|
|
{
|
|
unsigned long mask = SCU_PM_POWEROFF << (cpu * 8);
|
|
|
|
if ((__raw_readl(shmobile_scu_base + 8) & mask) == mask)
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int shmobile_smp_scu_cpu_kill(unsigned int cpu)
|
|
{
|
|
int k;
|
|
|
|
/* this function is running on another CPU than the offline target,
|
|
* here we need wait for shutdown code in platform_cpu_die() to
|
|
* finish before asking SoC-specific code to power off the CPU core.
|
|
*/
|
|
for (k = 0; k < 1000; k++) {
|
|
if (shmobile_smp_scu_psr_core_disabled(cpu))
|
|
return 1;
|
|
|
|
mdelay(1);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
#endif
|