/*-
 * Copyright (c) 2016 Michal Meloun <mmel@FreeBSD.org>
 * 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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 <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/cpu.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/sysctl.h>

#include <machine/bus.h>
#include <machine/cpu.h>

#include <dev/clk/clk.h>
#include <dev/ofw/ofw_bus_subr.h>

#include "tegra_soctherm_if.h"

enum therm_info {
        CORETEMP_TEMP,
        CORETEMP_DELTA,
        CORETEMP_RESOLUTION,
        CORETEMP_TJMAX,
};

struct tegra124_coretemp_softc {
        device_t                dev;
        int                     overheat_log;
        int                     core_max_temp;
        int                     cpu_id;
        device_t                tsens_dev;
        intptr_t                tsens_id;
};

static int
coretemp_get_val_sysctl(SYSCTL_HANDLER_ARGS)
{
        device_t dev;
        int val, temp, rv;
        struct tegra124_coretemp_softc *sc;
        enum therm_info type;
        char stemp[16];

        dev = (device_t) arg1;
        sc = device_get_softc(dev);
        type = arg2;

        rv = TEGRA_SOCTHERM_GET_TEMPERATURE(sc->tsens_dev, sc->dev,
             sc->tsens_id, &temp);
        if (rv != 0) {
                device_printf(sc->dev,
                    "Cannot read temperature sensor %d:  %d\n",
                    sc->tsens_id, rv);
                return (rv);
        }

        switch (type) {
        case CORETEMP_TEMP:
                val = temp / 100;
                val +=  2731;
                break;
        case CORETEMP_DELTA:
                val = (sc->core_max_temp - temp) / 1000;
                break;
        case CORETEMP_RESOLUTION:
                val = 1;
                break;
        case CORETEMP_TJMAX:
                val = sc->core_max_temp / 100;
                val +=  2731;
                break;
        }

        if ((temp > sc->core_max_temp)  && !sc->overheat_log) {
                sc->overheat_log = 1;

                /*
                 * Check for Critical Temperature Status and Critical
                 * Temperature Log.  It doesn't really matter if the
                 * current temperature is invalid because the "Critical
                 * Temperature Log" bit will tell us if the Critical
                 * Temperature has * been reached in past. It's not
                 * directly related to the current temperature.
                 *
                 * If we reach a critical level, allow devctl(4)
                 * to catch this and shutdown the system.
                 */
                device_printf(dev, "critical temperature detected, "
                    "suggest system shutdown\n");
                snprintf(stemp, sizeof(stemp), "%d", val);
                devctl_notify("coretemp", "Thermal", stemp,
                    "notify=0xcc");
        } else {
                sc->overheat_log = 0;
        }

        return (sysctl_handle_int(oidp, 0, val, req));
}

static int
tegra124_coretemp_ofw_parse(struct tegra124_coretemp_softc *sc)
{
        int rv, ncells;
        phandle_t node, xnode;
        pcell_t *cells;

        node = OF_peer(0);
        node = ofw_bus_find_child(node, "thermal-zones");
        if (node <= 0) {
                device_printf(sc->dev, "Cannot find 'thermal-zones'.\n");
                return (ENXIO);
        }

        node = ofw_bus_find_child(node, "cpu");
        if (node <= 0) {
                device_printf(sc->dev, "Cannot find 'cpu'\n");
                return (ENXIO);
        }
        rv = ofw_bus_parse_xref_list_alloc(node, "thermal-sensors",
            "#thermal-sensor-cells", 0, &xnode, &ncells, &cells);
        if (rv != 0) {
                device_printf(sc->dev,
                    "Cannot parse 'thermal-sensors' property.\n");
                return (ENXIO);
        }
        if (ncells != 1) {
                device_printf(sc->dev,
                    "Invalid format of 'thermal-sensors' property(%d).\n",
                    ncells);
                return (ENXIO);
        }

        sc->tsens_id = 0x100 + sc->cpu_id; //cells[0];
        OF_prop_free(cells);

        sc->tsens_dev = OF_device_from_xref(xnode);
        if (sc->tsens_dev == NULL) {
                device_printf(sc->dev,
                    "Cannot find thermal sensors device.");
                return (ENXIO);
        }
        return (0);
}

static void
tegra124_coretemp_identify(driver_t *driver, device_t parent)
{
        phandle_t root;

        root = OF_finddevice("/");
        if (!ofw_bus_node_is_compatible(root, "nvidia,tegra124"))
                return;
        if (device_find_child(parent, "tegra124_coretemp", DEVICE_UNIT_ANY) != NULL)
                return;
        if (BUS_ADD_CHILD(parent, 0, "tegra124_coretemp", DEVICE_UNIT_ANY) == NULL)
                device_printf(parent, "add child failed\n");
}

static int
tegra124_coretemp_probe(device_t dev)
{

        device_set_desc(dev, "CPU Thermal Sensor");
        return (0);
}

static int
tegra124_coretemp_attach(device_t dev)
{
        struct tegra124_coretemp_softc *sc;
        device_t pdev;
        struct sysctl_oid *oid;
        struct sysctl_ctx_list *ctx;
        int rv;

        sc = device_get_softc(dev);
        sc->dev = dev;
        sc->cpu_id = device_get_unit(dev);
        sc->core_max_temp = 102000;
        pdev = device_get_parent(dev);

        rv = tegra124_coretemp_ofw_parse(sc);
        if (rv != 0)
                return (rv);

        ctx = device_get_sysctl_ctx(dev);

        oid = SYSCTL_ADD_NODE(ctx,
            SYSCTL_CHILDREN(device_get_sysctl_tree(pdev)), OID_AUTO,
            "coretemp", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
            "Per-CPU thermal information");

        /*
         * Add the MIBs to dev.cpu.N and dev.cpu.N.coretemp.
         */
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(device_get_sysctl_tree(pdev)),
            OID_AUTO, "temperature", CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE,
            dev, CORETEMP_TEMP, coretemp_get_val_sysctl, "IK",
            "Current temperature");
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(oid), OID_AUTO, "delta",
            CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, dev, CORETEMP_DELTA,
            coretemp_get_val_sysctl, "I",
            "Delta between TCC activation and current temperature");
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(oid), OID_AUTO, "resolution",
            CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, dev, CORETEMP_RESOLUTION,
            coretemp_get_val_sysctl, "I",
            "Resolution of CPU thermal sensor");
        SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(oid), OID_AUTO, "tjmax",
            CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, dev, CORETEMP_TJMAX,
            coretemp_get_val_sysctl, "IK",
            "TCC activation temperature");

        return (0);
}

static int
tegra124_coretemp_detach(device_t dev)
{
        return (0);
}

static device_method_t tegra124_coretemp_methods[] = {
        /* Device interface */
        DEVMETHOD(device_identify,      tegra124_coretemp_identify),
        DEVMETHOD(device_probe,         tegra124_coretemp_probe),
        DEVMETHOD(device_attach,        tegra124_coretemp_attach),
        DEVMETHOD(device_detach,        tegra124_coretemp_detach),

        DEVMETHOD_END
};

static DEFINE_CLASS_0(tegra124_coretemp, tegra124_coretemp_driver,
    tegra124_coretemp_methods, sizeof(struct tegra124_coretemp_softc));
DRIVER_MODULE(tegra124_coretemp, cpu, tegra124_coretemp_driver, NULL, NULL);