freebsd-skq/sys/dev/sfxge/sfxge_dma.c
2012-12-04 09:32:43 +00:00

203 lines
5.1 KiB
C

/*-
* Copyright (c) 2010-2011 Solarflare Communications, Inc.
* All rights reserved.
*
* This software was developed in part by Philip Paeps under contract for
* Solarflare Communications, Inc.
*
* 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/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/bus.h>
#include <machine/bus.h>
#include "common/efx.h"
#include "sfxge.h"
static void
sfxge_dma_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error)
{
bus_addr_t *addr;
addr = arg;
if (error) {
*addr = 0;
return;
}
*addr = segs[0].ds_addr;
}
int
sfxge_dma_map_sg_collapse(bus_dma_tag_t tag, bus_dmamap_t map,
struct mbuf **mp, bus_dma_segment_t *segs, int *nsegs, int maxsegs)
{
bus_dma_segment_t *psegs;
struct mbuf *m;
int seg_count;
int defragged;
int err;
m = *mp;
defragged = err = seg_count = 0;
KASSERT(m->m_pkthdr.len, ("packet has zero header length"));
retry:
psegs = segs;
seg_count = 0;
if (m->m_next == NULL) {
sfxge_map_mbuf_fast(tag, map, m, segs);
*nsegs = 1;
return (0);
}
#if defined(__i386__) || defined(__amd64__)
while (m && seg_count < maxsegs) {
/*
* firmware doesn't like empty segments
*/
if (m->m_len != 0) {
seg_count++;
sfxge_map_mbuf_fast(tag, map, m, psegs);
psegs++;
}
m = m->m_next;
}
#else
err = bus_dmamap_load_mbuf_sg(tag, map, *mp, segs, &seg_count, 0);
#endif
if (seg_count == 0) {
err = EFBIG;
goto err_out;
} else if (err == EFBIG || seg_count >= maxsegs) {
if (!defragged) {
m = m_defrag(*mp, M_NOWAIT);
if (m == NULL) {
err = ENOBUFS;
goto err_out;
}
*mp = m;
defragged = 1;
goto retry;
}
err = EFBIG;
goto err_out;
}
*nsegs = seg_count;
err_out:
return (err);
}
void
sfxge_dma_free(efsys_mem_t *esmp)
{
bus_dmamap_unload(esmp->esm_tag, esmp->esm_map);
bus_dmamem_free(esmp->esm_tag, esmp->esm_base, esmp->esm_map);
bus_dma_tag_destroy(esmp->esm_tag);
esmp->esm_addr = 0;
esmp->esm_base = NULL;
}
int
sfxge_dma_alloc(struct sfxge_softc *sc, bus_size_t len, efsys_mem_t *esmp)
{
void *vaddr;
/* Create the child DMA tag. */
if (bus_dma_tag_create(sc->parent_dma_tag, PAGE_SIZE, 0,
MIN(0x3FFFFFFFFFFFUL, BUS_SPACE_MAXADDR), BUS_SPACE_MAXADDR, NULL,
NULL, len, 1, len, 0, NULL, NULL, &esmp->esm_tag) != 0) {
device_printf(sc->dev, "Couldn't allocate txq DMA tag\n");
return (ENOMEM);
}
/* Allocate kernel memory. */
if (bus_dmamem_alloc(esmp->esm_tag, (void **)&vaddr,
BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO,
&esmp->esm_map) != 0) {
device_printf(sc->dev, "Couldn't allocate DMA memory\n");
bus_dma_tag_destroy(esmp->esm_tag);
return (ENOMEM);
}
/* Load map into device memory. */
if (bus_dmamap_load(esmp->esm_tag, esmp->esm_map, vaddr, len,
sfxge_dma_cb, &esmp->esm_addr, 0) != 0) {
device_printf(sc->dev, "Couldn't load DMA mapping\n");
bus_dmamem_free(esmp->esm_tag, esmp->esm_base, esmp->esm_map);
bus_dma_tag_destroy(esmp->esm_tag);
return (ENOMEM);
}
/*
* The callback gets error information about the mapping
* and will have set our vaddr to NULL if something went
* wrong.
*/
if (vaddr == NULL)
return (ENOMEM);
esmp->esm_base = vaddr;
return (0);
}
void
sfxge_dma_fini(struct sfxge_softc *sc)
{
bus_dma_tag_destroy(sc->parent_dma_tag);
}
int
sfxge_dma_init(struct sfxge_softc *sc)
{
/* Create the parent dma tag. */
if (bus_dma_tag_create(bus_get_dma_tag(sc->dev), /* parent */
1, 0, /* algnmnt, boundary */
BUS_SPACE_MAXADDR, /* lowaddr */
BUS_SPACE_MAXADDR, /* highaddr */
NULL, NULL, /* filter, filterarg */
BUS_SPACE_MAXSIZE_32BIT, /* maxsize */
BUS_SPACE_UNRESTRICTED, /* nsegments */
BUS_SPACE_MAXSIZE_32BIT, /* maxsegsize */
0, /* flags */
NULL, NULL, /* lock, lockarg */
&sc->parent_dma_tag)) {
device_printf(sc->dev, "Cannot allocate parent DMA tag\n");
return (ENOMEM);
}
return (0);
}