// SPDX-License-Identifier: GPL-2.0-only
/*
 *  Copyright (C) 2002 ARM Ltd.
 *  All Rights Reserved
 */
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/smp.h>
#include <linux/io.h>
#include <linux/of_address.h>
#include <linux/vexpress.h>

#include <asm/mcpm.h>
#include <asm/smp_scu.h>
#include <asm/mach/map.h>

#include "platsmp.h"
#include "vexpress.h"

bool __init vexpress_smp_init_ops(void)
{
#ifdef CONFIG_MCPM
        int cpu;
        struct device_node *cpu_node, *cci_node;

        /*
         * The best way to detect a multi-cluster configuration
         * is to detect if the kernel can take over CCI ports
         * control. Loop over possible CPUs and check if CCI
         * port control is available.
         * Override the default vexpress_smp_ops if so.
         */
        for_each_possible_cpu(cpu) {
                bool available;

                cpu_node = of_get_cpu_node(cpu, NULL);
                if (WARN(!cpu_node, "Missing cpu device node!"))
                        return false;

                cci_node = of_parse_phandle(cpu_node, "cci-control-port", 0);
                available = cci_node && of_device_is_available(cci_node);
                of_node_put(cci_node);
                of_node_put(cpu_node);

                if (!available)
                        return false;
        }

        mcpm_smp_set_ops();
        return true;
#else
        return false;
#endif
}

static const struct of_device_id vexpress_smp_dt_scu_match[] __initconst = {
        { .compatible = "arm,cortex-a5-scu", },
        { .compatible = "arm,cortex-a9-scu", },
        {}
};

static void __init vexpress_smp_dt_prepare_cpus(unsigned int max_cpus)
{
        struct device_node *scu = of_find_matching_node(NULL,
                        vexpress_smp_dt_scu_match);

        if (scu)
                scu_enable(of_iomap(scu, 0));

        /*
         * Write the address of secondary startup into the
         * system-wide flags register. The boot monitor waits
         * until it receives a soft interrupt, and then the
         * secondary CPU branches to this address.
         */
        vexpress_flags_set(__pa_symbol(versatile_secondary_startup));
}

#ifdef CONFIG_HOTPLUG_CPU
static void vexpress_cpu_die(unsigned int cpu)
{
        versatile_immitation_cpu_die(cpu, 0x40);
}
#endif

const struct smp_operations vexpress_smp_dt_ops __initconst = {
        .smp_prepare_cpus       = vexpress_smp_dt_prepare_cpus,
        .smp_secondary_init     = versatile_secondary_init,
        .smp_boot_secondary     = versatile_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
        .cpu_die                = vexpress_cpu_die,
#endif
};