mcpm_platsmp.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/arch/arm/mach-vexpress/mcpm_platsmp.c
*
* Created by: Nicolas Pitre, November 2012
* Copyright: (C) 2012-2013 Linaro Limited
*
* Code to handle secondary CPU bringup and hotplug for the cluster power API.
*/
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
#include <asm/mcpm.h>
#include <asm/smp.h>
#include <asm/smp_plat.h>
static void cpu_to_pcpu(unsigned int cpu,
unsigned int *pcpu, unsigned int *pcluster)
{
unsigned int mpidr;
mpidr = cpu_logical_map(cpu);
*pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
*pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
}
static int mcpm_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
unsigned int pcpu, pcluster, ret;
extern void secondary_startup(void);
cpu_to_pcpu(cpu, &pcpu, &pcluster);
pr_debug("%s: logical CPU %d is physical CPU %d cluster %d\n",
__func__, cpu, pcpu, pcluster);
mcpm_set_entry_vector(pcpu, pcluster, NULL);
ret = mcpm_cpu_power_up(pcpu, pcluster);
if (ret)
return ret;
mcpm_set_entry_vector(pcpu, pcluster, secondary_startup);
arch_send_wakeup_ipi_mask(cpumask_of(cpu));
dsb_sev();
return 0;
}
static void mcpm_secondary_init(unsigned int cpu)
{
mcpm_cpu_powered_up();
}
#ifdef CONFIG_HOTPLUG_CPU
static int mcpm_cpu_kill(unsigned int cpu)
{
unsigned int pcpu, pcluster;
cpu_to_pcpu(cpu, &pcpu, &pcluster);
return !mcpm_wait_for_cpu_powerdown(pcpu, pcluster);
}
static bool mcpm_cpu_can_disable(unsigned int cpu)
{
/* We assume all CPUs may be shut down. */
return true;
}
static void mcpm_cpu_die(unsigned int cpu)
{
unsigned int mpidr, pcpu, pcluster;
mpidr = read_cpuid_mpidr();
pcpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
pcluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
mcpm_set_entry_vector(pcpu, pcluster, NULL);
mcpm_cpu_power_down();
}
#endif
static const struct smp_operations mcpm_smp_ops __initconst = {
.smp_boot_secondary = mcpm_boot_secondary,
.smp_secondary_init = mcpm_secondary_init,
#ifdef CONFIG_HOTPLUG_CPU
.cpu_kill = mcpm_cpu_kill,
.cpu_can_disable = mcpm_cpu_can_disable,
.cpu_die = mcpm_cpu_die,
#endif
};
void __init mcpm_smp_set_ops(void)
{
smp_set_ops(&mcpm_smp_ops);
}