/*-
 * Copyright (c) 1998 - 2004 Søren Schmidt <sos@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,
 *    without modification, immediately at the beginning of the file.
 * 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.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * 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 <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ata.h>
#include <sys/kernel.h>
#include <sys/endian.h>
#include <sys/malloc.h> 
#include <sys/lock.h>
#include <sys/sema.h>
#include <sys/taskqueue.h>
#include <vm/uma.h>
#include <sys/bus.h>
#include <machine/bus.h>
#include <sys/rman.h>
#include <dev/pci/pcivar.h>
#include <dev/ata/ata-all.h>
#include <dev/ata/ata-pci.h>

/* prototypes */
static void ata_dmaalloc(struct ata_channel *);
static void ata_dmafree(struct ata_channel *);
static void ata_dmasetupd_cb(void *, bus_dma_segment_t *, int, int);
static int ata_dmaload(struct ata_device *, caddr_t, int32_t, int);
static int ata_dmaunload(struct ata_channel *);

/* local vars */
static MALLOC_DEFINE(M_ATADMA, "ATA DMA", "ATA driver DMA");

/* misc defines */
#define MAXSEGSZ	PAGE_SIZE
#define MAXTABSZ	PAGE_SIZE
#define MAXCTLDMASZ	(2 * (MAXTABSZ + MAXPHYS))

struct ata_dc_cb_args {
    bus_addr_t maddr;
    int error;
};

void 
ata_dmainit(struct ata_channel *ch)
{
    if ((ch->dma = malloc(sizeof(struct ata_dma), M_ATADMA, M_NOWAIT|M_ZERO))) {
	ch->dma->alloc = ata_dmaalloc;
	ch->dma->free = ata_dmafree;
	ch->dma->load = ata_dmaload;
	ch->dma->unload = ata_dmaunload;
	ch->dma->alignment = 2;
	ch->dma->max_iosize = 64 * 1024;
	ch->dma->boundary = 64 * 1024;
    }
}


static void
ata_dmasetupc_cb(void *xsc, bus_dma_segment_t *segs, int nsegs, int error)
{
    struct ata_dc_cb_args *cba = (struct ata_dc_cb_args *)xsc;

    if (!(cba->error = error))
	cba->maddr = segs[0].ds_addr;
}

static void
ata_dmaalloc(struct ata_channel *ch)
{
    struct ata_dc_cb_args ccba;

    if (bus_dma_tag_create(NULL, 1, 0,
			   BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR,
			   NULL, NULL, MAXCTLDMASZ,
			   ATA_DMA_ENTRIES, BUS_SPACE_MAXSIZE_32BIT,
			   BUS_DMA_ALLOCNOW, NULL, NULL, &ch->dma->dmatag))
	goto error;

    if (bus_dma_tag_create(ch->dma->dmatag, PAGE_SIZE, PAGE_SIZE,
			   BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR,
			   NULL, NULL, MAXTABSZ, 1, MAXTABSZ,
			   BUS_DMA_ALLOCNOW, NULL, NULL, &ch->dma->cdmatag))
	goto error;

    if (bus_dma_tag_create(ch->dma->dmatag,ch->dma->alignment,ch->dma->boundary,
			   BUS_SPACE_MAXADDR_32BIT, BUS_SPACE_MAXADDR,
			   NULL, NULL, ch->dma->max_iosize, 
			   ATA_DMA_ENTRIES, ch->dma->boundary,
			   BUS_DMA_ALLOCNOW, NULL, NULL, &ch->dma->ddmatag))
	goto error;

    if (bus_dmamem_alloc(ch->dma->cdmatag, (void **)&ch->dma->dmatab, 0,
			 &ch->dma->cdmamap))
	goto error;

    if (bus_dmamap_load(ch->dma->cdmatag, ch->dma->cdmamap, ch->dma->dmatab,
			MAXTABSZ, ata_dmasetupc_cb, &ccba, 0) || ccba.error) {
	bus_dmamem_free(ch->dma->cdmatag, ch->dma->dmatab,ch->dma->cdmamap);
	goto error;
    }
    ch->dma->mdmatab = ccba.maddr;
    if (bus_dmamap_create(ch->dma->ddmatag, 0, &ch->dma->ddmamap))
	goto error;
    return;

error:
    ata_printf(ch, -1, "WARNING - DMA tag allocation failed, disabling DMA\n");
    ata_dmafree(ch);
    free(ch->dma, M_ATADMA);
    ch->dma = NULL;
}

static void
ata_dmafree(struct ata_channel *ch)
{
    if (ch->dma->mdmatab) {
	bus_dmamap_unload(ch->dma->cdmatag, ch->dma->cdmamap);
	bus_dmamem_free(ch->dma->cdmatag, ch->dma->dmatab, ch->dma->cdmamap);
	ch->dma->mdmatab = 0;
	ch->dma->cdmamap = NULL;
	ch->dma->dmatab = NULL;
    }
    if (ch->dma->ddmamap) {
	bus_dmamap_destroy(ch->dma->ddmatag, ch->dma->ddmamap);
	ch->dma->ddmamap = NULL;
    }
    if (ch->dma->cdmatag) {
	bus_dma_tag_destroy(ch->dma->cdmatag);
	ch->dma->cdmatag = NULL;
    }
    if (ch->dma->ddmatag) {
	bus_dma_tag_destroy(ch->dma->ddmatag);
	ch->dma->ddmatag = NULL;
    }
    if (ch->dma->dmatag) {
	bus_dma_tag_destroy(ch->dma->dmatag);
	ch->dma->dmatag = NULL;
    }
}

struct ata_dmasetup_data_cb_args {
    struct ata_dmaentry *dmatab;
    int error;
};

static void
ata_dmasetupd_cb(void *xsc, bus_dma_segment_t *segs, int nsegs, int error)
{
    struct ata_dmasetup_data_cb_args *cba =
	(struct ata_dmasetup_data_cb_args *)xsc;
    bus_size_t cnt;
    u_int32_t lastcount;
    int i, j;

    cba->error = error;
    if (error != 0)
	return;
    lastcount = j = 0;
    for (i = 0; i < nsegs; i++) {
	/*
	 * A maximum segment size was specified for bus_dma_tag_create, but
	 * some busdma code does not seem to honor this, so fix up if needed.
	 */
	for (cnt = 0; cnt < segs[i].ds_len; cnt += MAXSEGSZ, j++) {
	    cba->dmatab[j].base = htole32(segs[i].ds_addr + cnt);
	    lastcount = ulmin(segs[i].ds_len - cnt, MAXSEGSZ) & 0xffff;
	    cba->dmatab[j].count = htole32(lastcount);
	}
    }
    cba->dmatab[j - 1].count = htole32(lastcount | ATA_DMA_EOT);
}

static int
ata_dmaload(struct ata_device *atadev, caddr_t data, int32_t count, int dir)
{
    struct ata_channel *ch = atadev->channel;
    struct ata_dmasetup_data_cb_args cba;

    if (ch->dma->flags & ATA_DMA_ACTIVE) {
	ata_prtdev(atadev, "FAILURE - already active DMA on this device\n");
	return -1;
    }
    if (!count) {
	ata_prtdev(atadev, "FAILURE - zero length DMA transfer attempted\n");
	return -1;
    }
    if (((uintptr_t)data & (ch->dma->alignment - 1)) ||
	(count & (ch->dma->alignment - 1))) {
	ata_prtdev(atadev, "FAILURE - non aligned DMA transfer attempted\n");
	return -1;
    }
    if (count > ch->dma->max_iosize) {
	ata_prtdev(atadev,
		   "FAILURE - oversized DMA transfer attempted %d > %d\n",
		   count, ch->dma->max_iosize);
	return -1;
    }

    cba.dmatab = ch->dma->dmatab;

    bus_dmamap_sync(ch->dma->cdmatag, ch->dma->cdmamap, BUS_DMASYNC_PREWRITE);

    if (bus_dmamap_load(ch->dma->ddmatag, ch->dma->ddmamap, data, count,
			ata_dmasetupd_cb, &cba, 0) || cba.error)
	return -1;

    bus_dmamap_sync(ch->dma->ddmatag, ch->dma->ddmamap,
		    dir ? BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);

    ch->dma->cur_iosize = count;
    ch->dma->flags = dir ? (ATA_DMA_ACTIVE | ATA_DMA_READ) : ATA_DMA_ACTIVE;

    return 0;
}

int
ata_dmaunload(struct ata_channel *ch)
{
    bus_dmamap_sync(ch->dma->cdmatag, ch->dma->cdmamap, BUS_DMASYNC_POSTWRITE);

    bus_dmamap_sync(ch->dma->ddmatag, ch->dma->ddmamap,
		    (ch->dma->flags & ATA_DMA_READ) != 0 ?
		    BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
    bus_dmamap_unload(ch->dma->ddmatag, ch->dma->ddmamap);

    ch->dma->cur_iosize = 0;
    ch->dma->flags = 0;

    return 0;
}