linux-imx

/*

 * Copyright (C) 2014 Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>

 * Copyright (C) 2017 Stafford Horne <shorne@gmail.com>

 *

 * Based on arm64 and arc implementations

 * Copyright (C) 2013 ARM Ltd.

 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)

 *

 * This file is licensed under the terms of the GNU General Public License

 * version 2.  This program is licensed "as is" without any warranty of any

 * kind, whether express or implied.

 */

​

#include <linux/smp.h>

#include <linux/cpu.h>

#include <linux/sched.h>

#include <linux/irq.h>

#include <asm/cpuinfo.h>

#include <asm/mmu_context.h>

#include <asm/tlbflush.h>

#include <asm/cacheflush.h>

#include <asm/time.h>

​

static void (*smp_cross_call)(const struct cpumask *, unsigned int);

​

unsigned long secondary_release = -1;

struct thread_info *secondary_thread_info;

​

enum ipi_msg_type {

    IPI_WAKEUP,

    IPI_RESCHEDULE,

    IPI_CALL_FUNC,

    IPI_CALL_FUNC_SINGLE,

};

​

static DEFINE_SPINLOCK(boot_lock);

​

static void boot_secondary(unsigned int cpu, struct task_struct *idle)

{

    /*

     * set synchronisation state between this boot processor

     * and the secondary one

     */

    spin_lock(&boot_lock);

​

    secondary_release = cpu;

    smp_cross_call(cpumask_of(cpu), IPI_WAKEUP);

​

    /*

     * now the secondary core is starting up let it run its

     * calibrations, then wait for it to finish

     */

    spin_unlock(&boot_lock);

}

​

void __init smp_prepare_boot_cpu(void)

{

}

​

void __init smp_init_cpus(void)

{

    int i;

​

    for (i = 0; i < NR_CPUS; i++)

        set_cpu_possible(i, true);

}

​

void __init smp_prepare_cpus(unsigned int max_cpus)

{

    int i;

​

    /*

     * Initialise the present map, which describes the set of CPUs

     * actually populated at the present time.

     */

    for (i = 0; i < max_cpus; i++)

        set_cpu_present(i, true);

}

​

void __init smp_cpus_done(unsigned int max_cpus)

{

}

​

static DECLARE_COMPLETION(cpu_running);

​

int __cpu_up(unsigned int cpu, struct task_struct *idle)

{

    if (smp_cross_call == NULL) {

        pr_warn("CPU%u: failed to start, IPI controller missing",

            cpu);

        return -EIO;

    }