/*-
 * Copyright (c) 2018-2020 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/rman.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <machine/bus.h>

#include <arm64/coresight/coresight.h>

#include "coresight_if.h"

extern struct coresight_device_list cs_devs;

static struct coresight_device *
coresight_next_device(struct coresight_device *cs_dev,
    struct coresight_event *event)
{
        struct coresight_device *out;
        struct endpoint *out_endp;
        struct endpoint *endp;

        TAILQ_FOREACH(endp, &cs_dev->pdata->endpoints, link) {
                if (endp->input != 0)
                        continue;

                out = coresight_get_output_device(endp, &out_endp);
                if (out != NULL) {
                        if (LIST_EMPTY(&event->endplist)) {
                                /* Add source device */
                                endp->cs_dev = cs_dev;
                                LIST_INSERT_HEAD(&event->endplist, endp,
                                    endplink);
                        }

                        /* Add output device */
                        if (bootverbose)
                                printf("Adding device %s to the chain\n",
                                    device_get_nameunit(out->dev));
                        out_endp->cs_dev = out;
                        LIST_INSERT_HEAD(&event->endplist, out_endp, endplink);

                        return (out);
                }
        }

        return (NULL);
}

static int
coresight_build_list(struct coresight_device *cs_dev,
    struct coresight_event *event)
{
        struct coresight_device *out;

        out = cs_dev;
        while (out != NULL)
                out = coresight_next_device(out, event);

        return (0);
}

int
coresight_init_event(int cpu, struct coresight_event *event)
{
        struct coresight_device *cs_dev;
        struct endpoint *endp;

        /* Start building path from source device */
        TAILQ_FOREACH(cs_dev, &cs_devs, link) {
                if (cs_dev->dev_type == event->src &&
                    cs_dev->pdata->cpu == cpu) {
                        LIST_INIT(&event->endplist);
                        coresight_build_list(cs_dev, event);
                        break;
                }
        }

        /* Ensure Coresight is initialized for the CPU */
        TAILQ_FOREACH(cs_dev, &cs_devs, link) {
                if (cs_dev->dev_type == CORESIGHT_CPU_DEBUG &&
                    cs_dev->pdata->cpu == cpu)
                        CORESIGHT_INIT(cs_dev->dev);
        }

        /* Init all devices in the path */
        LIST_FOREACH(endp, &event->endplist, endplink) {
                cs_dev = endp->cs_dev;
                CORESIGHT_INIT(cs_dev->dev);
        }

        return (0);
}

void
coresight_enable(int cpu, struct coresight_event *event)
{
        struct coresight_device *cs_dev;
        struct endpoint *endp;

        LIST_FOREACH(endp, &event->endplist, endplink) {
                cs_dev = endp->cs_dev;
                CORESIGHT_ENABLE(cs_dev->dev, endp, event);
        }
}

void
coresight_disable(int cpu, struct coresight_event *event)
{
        struct coresight_device *cs_dev;
        struct endpoint *endp;

        LIST_FOREACH(endp, &event->endplist, endplink) {
                cs_dev = endp->cs_dev;
                CORESIGHT_DISABLE(cs_dev->dev, endp, event);
        }
}

void
coresight_read(int cpu, struct coresight_event *event)
{
        struct endpoint *endp;

        LIST_FOREACH(endp, &event->endplist, endplink)
                CORESIGHT_READ(endp->cs_dev->dev, endp, event);
}