// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright 2010-2011 Calxeda, Inc.
 * Copyright 2012 Pavel Machek <pavel@denx.de>
 * Based on platsmp.c, Copyright (C) 2002 ARM Ltd.
 * Copyright (C) 2012 Altera Corporation
 */
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>

#include <asm/cacheflush.h>
#include <asm/smp_scu.h>
#include <asm/smp_plat.h>

#include "core.h"

static int socfpga_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
        int trampoline_size = secondary_trampoline_end - secondary_trampoline;

        if (socfpga_cpu1start_addr) {
                /* This will put CPU #1 into reset. */
                writel(RSTMGR_MPUMODRST_CPU1,
                       rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST);

                memcpy(phys_to_virt(0), secondary_trampoline, trampoline_size);

                writel(__pa_symbol(secondary_startup),
                       sys_manager_base_addr + (socfpga_cpu1start_addr & 0x000000ff));

                flush_cache_all();
                smp_wmb();
                outer_clean_range(0, trampoline_size);

                /* This will release CPU #1 out of reset. */
                writel(0, rst_manager_base_addr + SOCFPGA_RSTMGR_MODMPURST);
        }

        return 0;
}

static int socfpga_a10_boot_secondary(unsigned int cpu, struct task_struct *idle)
{
        int trampoline_size = secondary_trampoline_end - secondary_trampoline;

        if (socfpga_cpu1start_addr) {
                writel(RSTMGR_MPUMODRST_CPU1, rst_manager_base_addr +
                       SOCFPGA_A10_RSTMGR_MODMPURST);
                memcpy(phys_to_virt(0), secondary_trampoline, trampoline_size);

                writel(__pa_symbol(secondary_startup),
                       sys_manager_base_addr + (socfpga_cpu1start_addr & 0x00000fff));

                flush_cache_all();
                smp_wmb();
                outer_clean_range(0, trampoline_size);

                /* This will release CPU #1 out of reset. */
                writel(0, rst_manager_base_addr + SOCFPGA_A10_RSTMGR_MODMPURST);
        }

        return 0;
}

static void __init socfpga_smp_prepare_cpus(unsigned int max_cpus)
{
        struct device_node *np;
        void __iomem *socfpga_scu_base_addr;

        np = of_find_compatible_node(NULL, NULL, "arm,cortex-a9-scu");
        if (!np) {
                pr_err("%s: missing scu\n", __func__);
                return;
        }

        socfpga_scu_base_addr = of_iomap(np, 0);
        if (!socfpga_scu_base_addr)
                return;
        scu_enable(socfpga_scu_base_addr);
}

#ifdef CONFIG_HOTPLUG_CPU
/*
 * platform-specific code to shutdown a CPU
 *
 * Called with IRQs disabled
 */
static void socfpga_cpu_die(unsigned int cpu)
{
        /* Do WFI. If we wake up early, go back into WFI */
        while (1)
                cpu_do_idle();
}

/*
 * We need a dummy function so that platform_can_cpu_hotplug() knows
 * we support CPU hotplug. However, the function does not need to do
 * anything, because CPUs going offline just do WFI. We could reset
 * the CPUs but it would increase power consumption.
 */
static int socfpga_cpu_kill(unsigned int cpu)
{
        return 1;
}
#endif

static const struct smp_operations socfpga_smp_ops __initconst = {
        .smp_prepare_cpus       = socfpga_smp_prepare_cpus,
        .smp_boot_secondary     = socfpga_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
        .cpu_die                = socfpga_cpu_die,
        .cpu_kill               = socfpga_cpu_kill,
#endif
};

static const struct smp_operations socfpga_a10_smp_ops __initconst = {
        .smp_prepare_cpus       = socfpga_smp_prepare_cpus,
        .smp_boot_secondary     = socfpga_a10_boot_secondary,
#ifdef CONFIG_HOTPLUG_CPU
        .cpu_die                = socfpga_cpu_die,
        .cpu_kill               = socfpga_cpu_kill,
#endif
};

CPU_METHOD_OF_DECLARE(socfpga_smp, "altr,socfpga-smp", &socfpga_smp_ops);
CPU_METHOD_OF_DECLARE(socfpga_a10_smp, "altr,socfpga-a10-smp", &socfpga_a10_smp_ops);