/*      $NetBSD: fwdma.c,v 1.18 2021/07/24 21:31:37 andvar Exp $        */
/*-
 * Copyright (c) 2003
 *      Hidetoshi Shimokawa. 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *
 *      This product includes software developed by Hidetoshi Shimokawa.
 *
 * 4. Neither the name of the author nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: fwdma.c,v 1.18 2021/07/24 21:31:37 andvar Exp $");
#if defined(__FreeBSD__)
__FBSDID("$FreeBSD: src/sys/dev/firewire/fwdma.c,v 1.9 2007/06/06 14:31:36 simokawa Exp $");
#endif

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/device.h>
#include <sys/systm.h>
#include <sys/types.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/kmem.h>
#include <sys/select.h>

#include <machine/vmparam.h>

#include <dev/ieee1394/firewire.h>
#include <dev/ieee1394/firewirereg.h>
#include <dev/ieee1394/fwdma.h>

#define BUS_SPACE_MAXSIZE_32BIT         0xffffffff


void *
fwdma_malloc(device_t dev, bus_dma_tag_t dmat, bus_dmamap_t *dmamap,
             bus_size_t size, int alignment, int flags)
{
        bus_dma_segment_t segs;
        int nsegs;
        int err;
        void *v_addr;

        err = bus_dmamem_alloc(dmat, size, alignment, 0, &segs, 1,
            &nsegs, flags);
        if (err) {
                aprint_error_dev(dev, "DMA memory allocation failed %d\n", err);
                return NULL;
        }

        err = bus_dmamem_map(dmat, &segs, nsegs, size, &v_addr, flags);
        if (err) {
                aprint_error_dev(dev, "DMA memory map failed %d\n", err);
                bus_dmamem_free(dmat, &segs, nsegs);
                return NULL;
        }

        if (*dmamap == NULL) {
                err = bus_dmamap_create(dmat, size, nsegs,
                    BUS_SPACE_MAXSIZE_32BIT, 0, flags, dmamap);
                if (err) {
                        aprint_error_dev(dev,
                            "DMA map create failed %d\n", err);
                        bus_dmamem_unmap(dmat, v_addr, size);
                        bus_dmamem_free(dmat, &segs, nsegs);
                        return NULL;
                }
        }

        err = bus_dmamap_load(dmat, *dmamap, v_addr, size, NULL, flags);
        if (err != 0) {
                aprint_error_dev(dev, "DMA map load failed %d\n", err);
                bus_dmamap_destroy(dmat, *dmamap);
                bus_dmamem_unmap(dmat, v_addr, size);
                bus_dmamem_free(dmat, &segs, nsegs);
                return NULL;
        }

        return v_addr;
}

void
fwdma_free(bus_dma_tag_t dmat, bus_dmamap_t dmamap, void *vaddr)
{
        bus_dma_segment_t *segs;

        /* XXX we shouldn't pass around the segs in the dmamap */
        const bus_size_t mapsize = dmamap->dm_mapsize;
        const int nsegs = dmamap->dm_nsegs;
        const size_t segssz = sizeof(bus_dma_segment_t) * nsegs;
        segs = kmem_alloc(segssz, KM_SLEEP);
        memcpy(segs, dmamap->dm_segs, segssz);
        
        bus_dmamap_unload(dmat, dmamap);
        bus_dmamem_unmap(dmat, vaddr, mapsize);
        bus_dmamem_free(dmat, segs, nsegs);
        bus_dmamap_destroy(dmat, dmamap);
        
        kmem_free(segs, segssz);
}


void *
fwdma_alloc_setup(device_t dev, bus_dma_tag_t dmat, bus_size_t size,
                  struct fwdma_alloc *dma, int alignment, int flags)
{

        dma->v_addr =
            fwdma_malloc(dev, dmat, &dma->dma_map, size, alignment, flags);
        if (dma->v_addr != NULL) {
                dma->dma_tag = dmat;
                dma->bus_addr = dma->dma_map->dm_segs[0].ds_addr;
        }
        return dma->v_addr;
}

/*
 * Allocate multisegment dma buffers
 * each segment size is equal to ssize except last segment.
 */
struct fwdma_alloc_multi *
fwdma_malloc_multiseg(struct firewire_comm *fc, int alignment, int esize, int n,
                      int flags)
{
        struct fwdma_alloc_multi *am;
        struct fwdma_seg *seg;
        bus_size_t ssize;
        size_t size;
        int nseg;

        if (esize > PAGE_SIZE) {
                /* round up to PAGE_SIZE */
                esize = ssize = roundup2(esize, PAGE_SIZE);
                nseg = n;
        } else {
                /* allocate PAGE_SIZE segment for small elements */
                ssize = rounddown(PAGE_SIZE, esize);
                nseg = howmany(n, ssize / esize);
        }
        size = sizeof(struct fwdma_alloc_multi) +
            sizeof(struct fwdma_seg) * nseg;
        am = (struct fwdma_alloc_multi *)malloc(size, M_FW, M_WAITOK | M_ZERO);
        if (am == NULL) {
                aprint_error_dev(fc->dev, "malloc failed\n");
                return NULL;
        }
        am->ssize = ssize;
        am->esize = esize;
        am->nseg = 0;
        am->dma_tag = fc->dmat;

        for (seg = am->seg; nseg--; seg++) {
                seg->v_addr = fwdma_malloc(fc->dev, am->dma_tag, &seg->dma_map,
                    ssize, alignment, flags);
                if (seg->v_addr == NULL) {
                        aprint_error_dev(fc->dev, "malloc_size failed %d\n",
                            am->nseg);
                        fwdma_free_multiseg(am);
                        return NULL;
                }
                seg->bus_addr = seg->dma_map->dm_segs[0].ds_addr;
                am->nseg++;
        }
        return am;
}

void
fwdma_free_multiseg(struct fwdma_alloc_multi *am)
{
        struct fwdma_seg *seg;

        for (seg = am->seg; am->nseg--; seg++)
                fwdma_free(am->dma_tag, seg->dma_map, seg->v_addr);
        free(am, M_FW);
}