/*-
 * Copyright (c) 2016 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.
 */

/* xDMA memcpy test driver. */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/kthread.h>
#include <sys/module.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/resource.h>
#include <sys/rman.h>

#include <machine/bus.h>

#include <dev/xdma/xdma.h>

#include <dev/fdt/fdt_common.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/ofw_bus_subr.h>

/*
 * To use this test add a compatible node to your dts, e.g.
 *
 *      xdma_test {
 *              compatible = "freebsd,xdma-test";
 *
 *              dmas = <&dma 0 0 0xffffffff>;
 *              dma-names = "test";
 *      };
 */

struct xdmatest_softc {
        device_t                dev;
        xdma_controller_t       *xdma;
        xdma_channel_t          *xchan;
        void                    *ih;
        struct intr_config_hook config_intrhook;
        char                    *src;
        char                    *dst;
        uint32_t                len;
        uintptr_t               src_phys;
        uintptr_t               dst_phys;
        bus_dma_tag_t           src_dma_tag;
        bus_dmamap_t            src_dma_map;
        bus_dma_tag_t           dst_dma_tag;
        bus_dmamap_t            dst_dma_map;
        struct mtx              mtx;
        int                     done;
        struct proc             *newp;
        struct xdma_request     req;
};

static int xdmatest_probe(device_t dev);
static int xdmatest_attach(device_t dev);
static int xdmatest_detach(device_t dev);

static int
xdmatest_intr(void *arg)
{
        struct xdmatest_softc *sc;

        sc = arg;

        sc->done = 1;

        mtx_lock(&sc->mtx);
        wakeup(sc);
        mtx_unlock(&sc->mtx);

        return (0);
}

static void
xdmatest_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nseg, int err)
{
        bus_addr_t *addr;

        if (err)
                return;

        addr = (bus_addr_t*)arg;
        *addr = segs[0].ds_addr;
}

static int
xdmatest_alloc_test_memory(struct xdmatest_softc *sc)
{
        int err;

        sc->len = (0x1000000 - 8); /* 16mb */
        sc->len = 8;

        /* Source memory. */

        err = bus_dma_tag_create(
            bus_get_dma_tag(sc->dev),
            1024, 0,                    /* alignment, boundary */
            BUS_SPACE_MAXADDR_32BIT,    /* lowaddr */
            BUS_SPACE_MAXADDR,          /* highaddr */
            NULL, NULL,                 /* filter, filterarg */
            sc->len, 1,                 /* maxsize, nsegments*/
            sc->len, 0,                 /* maxsegsize, flags */
            NULL, NULL,                 /* lockfunc, lockarg */
            &sc->src_dma_tag);
        if (err) {
                device_printf(sc->dev,
                    "%s: Can't create bus_dma tag.\n", __func__);
                return (-1);
        }

        err = bus_dmamem_alloc(sc->src_dma_tag, (void **)&sc->src,
            BUS_DMA_WAITOK | BUS_DMA_COHERENT, &sc->src_dma_map);
        if (err) {
                device_printf(sc->dev,
                    "%s: Can't allocate memory.\n", __func__);
                return (-1);
        }

        err = bus_dmamap_load(sc->src_dma_tag, sc->src_dma_map, sc->src,
            sc->len, xdmatest_dmamap_cb, &sc->src_phys, BUS_DMA_WAITOK);
        if (err) {
                device_printf(sc->dev,
                    "%s: Can't load DMA map.\n", __func__);
                return (-1);
        }

        /* Destination memory. */

        err = bus_dma_tag_create(
            bus_get_dma_tag(sc->dev),
            1024, 0,                    /* alignment, boundary */
            BUS_SPACE_MAXADDR_32BIT,    /* lowaddr */
            BUS_SPACE_MAXADDR,          /* highaddr */
            NULL, NULL,                 /* filter, filterarg */
            sc->len, 1,                 /* maxsize, nsegments*/
            sc->len, 0,                 /* maxsegsize, flags */
            NULL, NULL,                 /* lockfunc, lockarg */
            &sc->dst_dma_tag);
        if (err) {
                device_printf(sc->dev,
                    "%s: Can't create bus_dma tag.\n", __func__);
                return (-1);
        }

        err = bus_dmamem_alloc(sc->dst_dma_tag, (void **)&sc->dst,
            BUS_DMA_WAITOK | BUS_DMA_COHERENT, &sc->dst_dma_map);
        if (err) {
                device_printf(sc->dev,
                    "%s: Can't allocate memory.\n", __func__);
                return (-1);
        }

        err = bus_dmamap_load(sc->dst_dma_tag, sc->dst_dma_map, sc->dst,
            sc->len, xdmatest_dmamap_cb, &sc->dst_phys, BUS_DMA_WAITOK);
        if (err) {
                device_printf(sc->dev,
                    "%s: Can't load DMA map.\n", __func__);
                return (-1);
        }

        return (0);
}

static int
xdmatest_test(struct xdmatest_softc *sc)
{
        int err;
        int i;

        /* Get xDMA controller. */
        sc->xdma = xdma_ofw_get(sc->dev, "test");
        if (sc->xdma == NULL) {
                device_printf(sc->dev, "Can't find xDMA controller.\n");
                return (-1);
        }

        /* Alloc xDMA virtual channel. */
        sc->xchan = xdma_channel_alloc(sc->xdma);
        if (sc->xchan == NULL) {
                device_printf(sc->dev, "Can't alloc virtual DMA channel.\n");
                return (-1);
        }

        /* Setup callback. */
        err = xdma_setup_intr(sc->xchan, 0, xdmatest_intr, sc, &sc->ih);
        if (err) {
                device_printf(sc->dev, "Can't setup xDMA interrupt handler.\n");
                return (-1);
        }

        /* We are going to fill memory. */
        bus_dmamap_sync(sc->src_dma_tag, sc->src_dma_map, BUS_DMASYNC_PREWRITE);
        bus_dmamap_sync(sc->dst_dma_tag, sc->dst_dma_map, BUS_DMASYNC_PREWRITE);

        /* Fill memory. */
        for (i = 0; i < sc->len; i++) {
                sc->src[i] = (i & 0xff);
                sc->dst[i] = 0;
        }

        sc->req.type = XR_TYPE_PHYS_ADDR;
        sc->req.direction = XDMA_MEM_TO_MEM;
        sc->req.src_addr = sc->src_phys;
        sc->req.dst_addr = sc->dst_phys;
        sc->req.src_width = 4;
        sc->req.dst_width = 4;
        sc->req.block_len = sc->len;
        sc->req.block_num = 1;

        err = xdma_request(sc->xchan, sc->src_phys, sc->dst_phys, sc->len);
        if (err != 0) {
                device_printf(sc->dev, "Can't configure virtual channel.\n");
                return (-1);
        }

        /* Start operation. */
        xdma_begin(sc->xchan);

        return (0);
}

static int
xdmatest_verify(struct xdmatest_softc *sc)
{
        int err;
        int i;

        /* We have memory updated by DMA controller. */
        bus_dmamap_sync(sc->src_dma_tag, sc->src_dma_map, BUS_DMASYNC_POSTREAD);
        bus_dmamap_sync(sc->dst_dma_tag, sc->dst_dma_map, BUS_DMASYNC_POSTWRITE);

        for (i = 0; i < sc->len; i++) {
                if (sc->dst[i] != sc->src[i]) {
                        device_printf(sc->dev,
                            "%s: Test failed: iter %d\n", __func__, i);
                        return (-1);
                }
        }

        err = xdma_channel_free(sc->xchan);
        if (err != 0) {
                device_printf(sc->dev,
                    "%s: Test failed: can't deallocate channel.\n", __func__);
                return (-1);
        }

        err = xdma_put(sc->xdma);
        if (err != 0) {
                device_printf(sc->dev,
                    "%s: Test failed: can't deallocate xDMA.\n", __func__);
                return (-1);
        }

        return (0);
}

static void
xdmatest_worker(void *arg)
{
        struct xdmatest_softc *sc;
        int timeout;
        int err;

        sc = arg;

        device_printf(sc->dev, "Worker %d started.\n",
            device_get_unit(sc->dev));

        while (1) {
                sc->done = 0;

                mtx_lock(&sc->mtx);

                if (xdmatest_test(sc) != 0) {
                        mtx_unlock(&sc->mtx);
                        device_printf(sc->dev,
                            "%s: Test failed.\n", __func__);
                        break;
                }

                timeout = 100;

                do {
                        mtx_sleep(sc, &sc->mtx, 0, "xdmatest_wait", hz);
                } while (timeout-- && sc->done == 0);

                if (timeout != 0) {
                        err = xdmatest_verify(sc);
                        if (err == 0) {
                                /* Test succeeded. */
                                mtx_unlock(&sc->mtx);
                                continue;
                        }
                }

                mtx_unlock(&sc->mtx);
                device_printf(sc->dev,
                    "%s: Test failed.\n", __func__);
                break;
        }
}

static void
xdmatest_delayed_attach(void *arg)
{
        struct xdmatest_softc *sc;

        sc = arg;

        if (kproc_create(xdmatest_worker, (void *)sc, &sc->newp, 0, 0,
            "xdmatest_worker") != 0) {
                device_printf(sc->dev,
                    "%s: Failed to create worker thread.\n", __func__);
        }

        config_intrhook_disestablish(&sc->config_intrhook);
}

static int
xdmatest_probe(device_t dev)
{

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

        if (!ofw_bus_is_compatible(dev, "freebsd,xdma-test"))
                return (ENXIO);

        device_set_desc(dev, "xDMA test driver");

        return (BUS_PROBE_DEFAULT);
}

static int
xdmatest_attach(device_t dev)
{
        struct xdmatest_softc *sc;
        int err;

        sc = device_get_softc(dev);
        sc->dev = dev;

        mtx_init(&sc->mtx, device_get_nameunit(dev), "xdmatest", MTX_DEF);

        /* Allocate test memory */
        err = xdmatest_alloc_test_memory(sc);
        if (err != 0) {
                device_printf(sc->dev, "Can't allocate test memory.\n");
                return (-1);
        }

        /* We'll run test later, but before / mount. */
        sc->config_intrhook.ich_func = xdmatest_delayed_attach;
        sc->config_intrhook.ich_arg = sc;
        if (config_intrhook_establish(&sc->config_intrhook) != 0)
                device_printf(dev, "config_intrhook_establish failed\n");

        return (0);
}

static int
xdmatest_detach(device_t dev)
{
        struct xdmatest_softc *sc;

        sc = device_get_softc(dev);

        bus_dmamap_unload(sc->src_dma_tag, sc->src_dma_map);
        bus_dmamem_free(sc->src_dma_tag, sc->src, sc->src_dma_map);
        bus_dma_tag_destroy(sc->src_dma_tag);

        bus_dmamap_unload(sc->dst_dma_tag, sc->dst_dma_map);
        bus_dmamem_free(sc->dst_dma_tag, sc->dst, sc->dst_dma_map);
        bus_dma_tag_destroy(sc->dst_dma_tag);

        return (0);
}

static device_method_t xdmatest_methods[] = {
        /* Device interface */
        DEVMETHOD(device_probe,                 xdmatest_probe),
        DEVMETHOD(device_attach,                xdmatest_attach),
        DEVMETHOD(device_detach,                xdmatest_detach),

        DEVMETHOD_END
};

static driver_t xdmatest_driver = {
        "xdmatest",
        xdmatest_methods,
        sizeof(struct xdmatest_softc),
};

DRIVER_MODULE(xdmatest, simplebus, xdmatest_driver, 0, 0);