/* $NetBSD: psci_fdt.c,v 1.22 2026/05/15 22:44:58 jmcneill Exp $ */

/*-
 * Copyright (c) 2017-2026 Jared McNeill <jmcneill@invisible.ca>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include "opt_multiprocessor.h"

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: psci_fdt.c,v 1.22 2026/05/15 22:44:58 jmcneill Exp $");

#include <sys/param.h>
#include <sys/atomic.h>
#include <sys/bus.h>
#include <sys/device.h>
#include <sys/kernel.h>
#include <sys/systm.h>

#include <dev/fdt/fdtvar.h>

#include <arm/arm/smccc.h>
#include <arm/arm/psci.h>
#include <arm/fdt/psci_fdtvar.h>

static int      psci_fdt_match(device_t, cfdata_t, void *);
static void     psci_fdt_attach(device_t, device_t, void *);

static int      psci_fdt_init(const int);

static const struct device_compatible_entry compat_data[] = {
        { .compat = "arm,psci" },
        { .compat = "arm,psci-0.2" },
        { .compat = "arm,psci-1.0" },
        DEVICE_COMPAT_EOL
};

CFATTACH_DECL_NEW(psci_fdt, 0, psci_fdt_match, psci_fdt_attach, NULL, NULL);

static void
psci_fdt_power_reset(device_t dev)
{
        delay(500000);
        psci_system_reset();
}

static void
psci_fdt_power_poweroff(device_t dev)
{
        delay(500000);
        psci_poweroff();
}

static const struct fdtbus_power_controller_func psci_power_funcs = {
        .reset = psci_fdt_power_reset,
        .poweroff = psci_fdt_power_poweroff,
};

static int
psci_fdt_match(device_t parent, cfdata_t cf, void *aux)
{
        struct fdt_attach_args * const faa = aux;

        return of_compatible_match(faa->faa_phandle, compat_data);
}

static void
psci_fdt_attach(device_t parent, device_t self, void *aux)
{
        struct fdt_attach_args * const faa = aux;
        const int phandle = faa->faa_phandle;

        psci_fdt_init(phandle);

        const uint32_t ver = psci_version();
        const u_int ver_maj = __SHIFTOUT(ver, PSCI_VERSION_MAJOR);
        const u_int ver_min = __SHIFTOUT(ver, PSCI_VERSION_MINOR);

        aprint_naive("\n");
        aprint_normal(": PSCI %u.%u\n", ver_maj, ver_min);

        fdtbus_register_power_controller(self, phandle,
            &psci_power_funcs);
}

static int
psci_fdt_init(const int phandle)
{
        const char *method, *psciver;
        uint32_t val;

        method = fdtbus_get_string(phandle, "method");
        psciver = fdtbus_get_string(phandle, "compatible");
        if (method == NULL || psciver == NULL) {
                aprint_error("PSCI: missing required property on /psci\n");
                return EINVAL;
        }

        if (strcmp(method, "smc") == 0)
                psci_init(psci_call_smc);
        else if (strcmp(method, "hvc") == 0)
                psci_init(psci_call_hvc);
        else {
                aprint_error("PSCI: unsupported method '%s'\n", method);
                return EINVAL;
        }

        /*
         * If the first compatible string is "arm,psci" then we
         * are dealing with PSCI 0.1
         */
        if (strcmp(psciver, "arm,psci") == 0) {
                psci_clearfunc();
                if (of_getprop_uint32(phandle, "cpu_on", &val) == 0)
                        psci_setfunc(PSCI_FUNC_CPU_ON, val);
        }

        smccc_probe();

        return 0;
}

int
psci_fdt_preinit(void)
{
        const int phandle = OF_finddevice("/psci");
        if (phandle == -1) {
                aprint_error("PSCI: no /psci node found\n");
                return ENODEV;
        }

        return psci_fdt_init(phandle);
}

void
psci_fdt_reset(void)
{
        if (psci_fdt_preinit() != 0) {
                aprint_error("PSCI: reset failed\n");
                return;
        }

        psci_system_reset();
}