1 /*- 2 * Copyright (c) 2010-2011 Solarflare Communications, Inc. 3 * All rights reserved. 4 * 5 * This software was developed in part by Philip Paeps under contract for 6 * Solarflare Communications, Inc. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include <sys/param.h> 34 #include <sys/bus.h> 35 36 #include <machine/bus.h> 37 38 #include "common/efx.h" 39 40 #include "sfxge.h" 41 42 static void 43 sfxge_dma_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error) 44 { 45 bus_addr_t *addr; 46 47 addr = arg; 48 49 if (error) { 50 *addr = 0; 51 return; 52 } 53 54 *addr = segs[0].ds_addr; 55 } 56 57 int 58 sfxge_dma_map_sg_collapse(bus_dma_tag_t tag, bus_dmamap_t map, 59 struct mbuf **mp, bus_dma_segment_t *segs, int *nsegs, int maxsegs) 60 { 61 bus_dma_segment_t *psegs; 62 struct mbuf *m; 63 int seg_count; 64 int defragged; 65 int err; 66 67 m = *mp; 68 defragged = err = seg_count = 0; 69 70 KASSERT(m->m_pkthdr.len, ("packet has zero header length")); 71 72 retry: 73 psegs = segs; 74 seg_count = 0; 75 if (m->m_next == NULL) { 76 sfxge_map_mbuf_fast(tag, map, m, segs); 77 *nsegs = 1; 78 return (0); 79 } 80 #if defined(__i386__) || defined(__amd64__) 81 while (m && seg_count < maxsegs) { 82 /* 83 * firmware doesn't like empty segments 84 */ 85 if (m->m_len != 0) { 86 seg_count++; 87 sfxge_map_mbuf_fast(tag, map, m, psegs); 88 psegs++; 89 } 90 m = m->m_next; 91 } 92 #else 93 err = bus_dmamap_load_mbuf_sg(tag, map, *mp, segs, &seg_count, 0); 94 #endif 95 if (seg_count == 0) { 96 err = EFBIG; 97 goto err_out; 98 } else if (err == EFBIG || seg_count >= maxsegs) { 99 if (!defragged) { 100 m = m_defrag(*mp, M_NOWAIT); 101 if (m == NULL) { 102 err = ENOBUFS; 103 goto err_out; 104 } 105 *mp = m; 106 defragged = 1; 107 goto retry; 108 } 109 err = EFBIG; 110 goto err_out; 111 } 112 *nsegs = seg_count; 113 114 err_out: 115 return (err); 116 } 117 118 void 119 sfxge_dma_free(efsys_mem_t *esmp) 120 { 121 122 bus_dmamap_unload(esmp->esm_tag, esmp->esm_map); 123 bus_dmamem_free(esmp->esm_tag, esmp->esm_base, esmp->esm_map); 124 bus_dma_tag_destroy(esmp->esm_tag); 125 126 esmp->esm_addr = 0; 127 esmp->esm_base = NULL; 128 } 129 130 int 131 sfxge_dma_alloc(struct sfxge_softc *sc, bus_size_t len, efsys_mem_t *esmp) 132 { 133 void *vaddr; 134 135 /* Create the child DMA tag. */ 136 if (bus_dma_tag_create(sc->parent_dma_tag, PAGE_SIZE, 0, 137 MIN(0x3FFFFFFFFFFFUL, BUS_SPACE_MAXADDR), BUS_SPACE_MAXADDR, NULL, 138 NULL, len, 1, len, 0, NULL, NULL, &esmp->esm_tag) != 0) { 139 device_printf(sc->dev, "Couldn't allocate txq DMA tag\n"); 140 return (ENOMEM); 141 } 142 143 /* Allocate kernel memory. */ 144 if (bus_dmamem_alloc(esmp->esm_tag, (void **)&vaddr, 145 BUS_DMA_WAITOK | BUS_DMA_COHERENT | BUS_DMA_ZERO, 146 &esmp->esm_map) != 0) { 147 device_printf(sc->dev, "Couldn't allocate DMA memory\n"); 148 bus_dma_tag_destroy(esmp->esm_tag); 149 return (ENOMEM); 150 } 151 152 /* Load map into device memory. */ 153 if (bus_dmamap_load(esmp->esm_tag, esmp->esm_map, vaddr, len, 154 sfxge_dma_cb, &esmp->esm_addr, 0) != 0) { 155 device_printf(sc->dev, "Couldn't load DMA mapping\n"); 156 bus_dmamem_free(esmp->esm_tag, esmp->esm_base, esmp->esm_map); 157 bus_dma_tag_destroy(esmp->esm_tag); 158 return (ENOMEM); 159 } 160 161 /* 162 * The callback gets error information about the mapping 163 * and will have set our vaddr to NULL if something went 164 * wrong. 165 */ 166 if (vaddr == NULL) 167 return (ENOMEM); 168 169 esmp->esm_base = vaddr; 170 171 return (0); 172 } 173 174 void 175 sfxge_dma_fini(struct sfxge_softc *sc) 176 { 177 178 bus_dma_tag_destroy(sc->parent_dma_tag); 179 } 180 181 int 182 sfxge_dma_init(struct sfxge_softc *sc) 183 { 184 185 /* Create the parent dma tag. */ 186 if (bus_dma_tag_create(bus_get_dma_tag(sc->dev), /* parent */ 187 1, 0, /* algnmnt, boundary */ 188 BUS_SPACE_MAXADDR, /* lowaddr */ 189 BUS_SPACE_MAXADDR, /* highaddr */ 190 NULL, NULL, /* filter, filterarg */ 191 BUS_SPACE_MAXSIZE_32BIT, /* maxsize */ 192 BUS_SPACE_UNRESTRICTED, /* nsegments */ 193 BUS_SPACE_MAXSIZE_32BIT, /* maxsegsize */ 194 0, /* flags */ 195 NULL, NULL, /* lock, lockarg */ 196 &sc->parent_dma_tag)) { 197 device_printf(sc->dev, "Cannot allocate parent DMA tag\n"); 198 return (ENOMEM); 199 } 200 201 return (0); 202 } 203