/*-
 * Copyright (c) 2015 Ruslan Bukin <br@bsdpad.com>
 * All rights reserved.
 *
 * This software was developed by SRI International and the University of
 * Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237)
 * ("CTSRD"), as part of the DARPA CRASH research programme.
 *
 * 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/kernel.h>
#include <sys/module.h>
#include <sys/rman.h>

#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>

#include "pmu.h"

static struct ofw_compat_data compat_data[] = {
        {"arm,armv8-pmuv3",     1},
        {"arm,cortex-a77-pmu",  1},
        {"arm,cortex-a76-pmu",  1},
        {"arm,cortex-a75-pmu",  1},
        {"arm,cortex-a73-pmu",  1},
        {"arm,cortex-a72-pmu",  1},
        {"arm,cortex-a65-pmu",  1},
        {"arm,cortex-a57-pmu",  1},
        {"arm,cortex-a55-pmu",  1},
        {"arm,cortex-a53-pmu",  1},
        {"arm,cortex-a34-pmu",  1},

        {"arm,cortex-a17-pmu",  1},
        {"arm,cortex-a15-pmu",  1},
        {"arm,cortex-a12-pmu",  1},
        {"arm,cortex-a9-pmu",   1},
        {"arm,cortex-a8-pmu",   1},
        {"arm,cortex-a7-pmu",   1},
        {"arm,cortex-a5-pmu",   1},
        {"arm,arm11mpcore-pmu", 1},
        {"arm,arm1176-pmu",     1},
        {"arm,arm1136-pmu",     1},
        {"qcom,krait-pmu",      1},
        {NULL,                  0}
};

static int
pmu_fdt_probe(device_t dev)
{

        if (!ofw_bus_status_okay(dev))
                return (ENXIO);

        if (ofw_bus_search_compatible(dev, compat_data)->ocd_data != 0) {
                device_set_desc(dev, "Performance Monitoring Unit");
                return (BUS_PROBE_DEFAULT);
        }

        return (ENXIO);
}

static int
pmu_parse_affinity(device_t dev, struct pmu_softc *sc, struct pmu_intr *irq,
    phandle_t xref, uint32_t mpidr)
{
        struct pcpu *pcpu;
        int i, err;


        if (xref  != 0) {
                err = OF_getencprop(OF_node_from_xref(xref), "reg", &mpidr,
                    sizeof(mpidr));
                if (err < 0) {
                        device_printf(dev, "missing 'reg' property\n");
                                return (ENXIO);
                }
        }

        for (i = 0; i < MAXCPU; i++) {
                pcpu = pcpu_find(i);
                if (pcpu != NULL && PCPU_GET_MPIDR(pcpu) == mpidr) {
                        irq->cpuid = i;
                        return (0);
                }
        }

        device_printf(dev, "Cannot find CPU with MPIDR: 0x%08X\n", mpidr);
        return (ENXIO);
}

static int
pmu_parse_intr(device_t dev, struct pmu_softc *sc)
{
        bool has_affinity;
        phandle_t node, *cpus;
        int rid, err, ncpus, i;


        node = ofw_bus_get_node(dev);
        has_affinity = OF_hasprop(node, "interrupt-affinity");

        for (i = 0; i < MAX_RLEN; i++)
                sc->irq[i].cpuid = -1;

        cpus = NULL;
        if (has_affinity) {
                ncpus = OF_getencprop_alloc_multi(node, "interrupt-affinity",
                    sizeof(*cpus), (void **)&cpus);
                if (ncpus < 0) {
                        device_printf(dev,
                            "Cannot read interrupt affinity property\n");
                        return (ENXIO);
                }
        }

        /* Process first interrupt */
        rid = 0;
        sc->irq[0].res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
            RF_ACTIVE | RF_SHAREABLE);

        if (sc->irq[0].res == NULL) {
                device_printf(dev, "Cannot get interrupt\n");
                err = ENXIO;
                goto done;
        }

        /* Check if PMU have one per-CPU interrupt */
        if (intr_is_per_cpu(sc->irq[0].res)) {
                if (has_affinity) {
                        device_printf(dev,
                            "Per CPU interrupt have declared affinity\n");
                        err = ENXIO;
                        goto done;
                }
                return (0);
        }

        /*
         * PMU with set of generic interrupts (one per core)
         * Each one must be binded to exact core.
         */
        err = pmu_parse_affinity(dev, sc, sc->irq + 0,
            has_affinity ? cpus[0] : 0, 0);
        if (err != 0) {
                device_printf(dev, "Cannot parse affinity for CPUid: 0\n");
                goto done;
        }

        for (i = 1; i < MAX_RLEN; i++) {
                rid = i;
                sc->irq[i].res = bus_alloc_resource_any(dev, SYS_RES_IRQ,
                    &rid, RF_ACTIVE | RF_SHAREABLE);
                if (sc->irq[i].res == NULL)
                        break;

                if (intr_is_per_cpu(sc->irq[i].res))
                {
                        device_printf(dev, "Unexpected per CPU interrupt\n");
                        err = ENXIO;
                        goto done;
                }

                if (has_affinity && i >= ncpus) {
                        device_printf(dev, "Missing value in interrupt "
                            "affinity property\n");
                        err = ENXIO;
                        goto done;
                }

                err = pmu_parse_affinity(dev, sc, sc->irq + i,
                    has_affinity ? cpus[i] : 0, i);
                if (err != 0) {
                        device_printf(dev,
                           "Cannot parse affinity for CPUid: %d.\n", i);
                        goto done;
                }
        }
        err = 0;
done:
        OF_prop_free(cpus);
        return (err);
}

static int
pmu_fdt_attach(device_t dev)
{
        struct pmu_softc *sc;
        int err;

        sc = device_get_softc(dev);
        err = pmu_parse_intr(dev, sc);
        if (err != 0)
                return (err);

        return (pmu_attach(dev));
}

static device_method_t pmu_fdt_methods[] = {
        DEVMETHOD(device_probe,         pmu_fdt_probe),
        DEVMETHOD(device_attach,        pmu_fdt_attach),
        { 0, 0 }
};

static driver_t pmu_fdt_driver = {
        "pmu",
        pmu_fdt_methods,
        sizeof(struct pmu_softc),
};

DRIVER_MODULE(pmu, simplebus, pmu_fdt_driver, 0, 0);