// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * PPC476 board specific routines
 *
 * Copyright 2010 Torez Smith, IBM Corporation.
 *
 * Based on earlier code:
 *    Matt Porter <mporter@kernel.crashing.org>
 *    Copyright 2002-2005 MontaVista Software Inc.
 *
 *    Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
 *    Copyright (c) 2003-2005 Zultys Technologies
 *
 *    Rewritten and ported to the merged powerpc tree:
 *    Copyright 2007 David Gibson <dwg@au1.ibm.com>, IBM Corporation.
 */

#include <linux/init.h>
#include <linux/of_platform.h>
#include <linux/rtc.h>

#include <asm/machdep.h>
#include <asm/prom.h>
#include <asm/udbg.h>
#include <asm/time.h>
#include <asm/uic.h>
#include <asm/ppc4xx.h>
#include <asm/mpic.h>
#include <asm/mmu.h>

static const struct of_device_id iss4xx_of_bus[] __initconst = {
        { .compatible = "ibm,plb4", },
        { .compatible = "ibm,plb6", },
        { .compatible = "ibm,opb", },
        { .compatible = "ibm,ebc", },
        {},
};

static int __init iss4xx_device_probe(void)
{
        of_platform_bus_probe(NULL, iss4xx_of_bus, NULL);
        of_instantiate_rtc();

        return 0;
}
machine_device_initcall(iss4xx, iss4xx_device_probe);

/* We can have either UICs or MPICs */
static void __init iss4xx_init_irq(void)
{
        struct device_node *np;

        /* Find top level interrupt controller */
        for_each_node_with_property(np, "interrupt-controller") {
                if (!of_property_present(np, "interrupts"))
                        break;
        }
        if (np == NULL)
                panic("Can't find top level interrupt controller");

        /* Check type and do appropriate initialization */
        if (of_device_is_compatible(np, "ibm,uic")) {
                uic_init_tree();
                ppc_md.get_irq = uic_get_irq;
#ifdef CONFIG_MPIC
        } else if (of_device_is_compatible(np, "chrp,open-pic")) {
                /* The MPIC driver will get everything it needs from the
                 * device-tree, just pass 0 to all arguments
                 */
                struct mpic *mpic = mpic_alloc(np, 0, MPIC_NO_RESET, 0, 0, " MPIC     ");
                BUG_ON(mpic == NULL);
                mpic_init(mpic);
                ppc_md.get_irq = mpic_get_irq;
#endif
        } else
                panic("Unrecognized top level interrupt controller");
}

#ifdef CONFIG_SMP
static void smp_iss4xx_setup_cpu(int cpu)
{
        mpic_setup_this_cpu();
}

static int smp_iss4xx_kick_cpu(int cpu)
{
        struct device_node *cpunode = of_get_cpu_node(cpu, NULL);
        const u64 *spin_table_addr_prop;
        u32 *spin_table;
        extern void start_secondary_47x(void);

        BUG_ON(cpunode == NULL);

        /* Assume spin table. We could test for the enable-method in
         * the device-tree but currently there's little point as it's
         * our only supported method
         */
        spin_table_addr_prop = of_get_property(cpunode, "cpu-release-addr",
                                               NULL);
        if (spin_table_addr_prop == NULL) {
                pr_err("CPU%d: Can't start, missing cpu-release-addr !\n", cpu);
                return -ENOENT;
        }

        /* Assume it's mapped as part of the linear mapping. This is a bit
         * fishy but will work fine for now
         */
        spin_table = (u32 *)__va(*spin_table_addr_prop);
        pr_debug("CPU%d: Spin table mapped at %p\n", cpu, spin_table);

        spin_table[3] = cpu;
        smp_wmb();
        spin_table[1] = __pa(start_secondary_47x);
        mb();

        return 0;
}

static struct smp_ops_t iss_smp_ops = {
        .probe          = smp_mpic_probe,
        .message_pass   = smp_mpic_message_pass,
        .setup_cpu      = smp_iss4xx_setup_cpu,
        .kick_cpu       = smp_iss4xx_kick_cpu,
        .give_timebase  = smp_generic_give_timebase,
        .take_timebase  = smp_generic_take_timebase,
};

static void __init iss4xx_smp_init(void)
{
        if (mmu_has_feature(MMU_FTR_TYPE_47x))
                smp_ops = &iss_smp_ops;
}

#else /* CONFIG_SMP */
static void __init iss4xx_smp_init(void) { }
#endif /* CONFIG_SMP */

static void __init iss4xx_setup_arch(void)
{
        iss4xx_smp_init();
}

define_machine(iss4xx) {
        .name                   = "ISS-4xx",
        .compatible             = "ibm,iss-4xx",
        .progress               = udbg_progress,
        .init_IRQ               = iss4xx_init_irq,
        .setup_arch             = iss4xx_setup_arch,
        .restart                = ppc4xx_reset_system,
};