bus_dma.h revision 104486
1/* $NetBSD: bus.h,v 1.12 1997/10/01 08:25:15 fvdl Exp $ */ 2 3/*- 4 * Copyright (c) 1996, 1997 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the NetBSD 22 * Foundation, Inc. and its contributors. 23 * 4. Neither the name of The NetBSD Foundation nor the names of its 24 * contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37 * POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40/* 41 * Copyright (c) 1996 Charles M. Hannum. All rights reserved. 42 * Copyright (c) 1996 Christopher G. Demetriou. All rights reserved. 43 * 44 * Redistribution and use in source and binary forms, with or without 45 * modification, are permitted provided that the following conditions 46 * are met: 47 * 1. Redistributions of source code must retain the above copyright 48 * notice, this list of conditions and the following disclaimer. 49 * 2. Redistributions in binary form must reproduce the above copyright 50 * notice, this list of conditions and the following disclaimer in the 51 * documentation and/or other materials provided with the distribution. 52 * 3. All advertising materials mentioning features or use of this software 53 * must display the following acknowledgement: 54 * This product includes software developed by Christopher G. Demetriou 55 * for the NetBSD Project. 56 * 4. The name of the author may not be used to endorse or promote products 57 * derived from this software without specific prior written permission 58 * 59 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 60 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 61 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 62 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 63 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 64 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 65 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 66 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 67 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 68 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 69 */ 70/* $FreeBSD: head/sys/sys/bus_dma.h 104486 2002-10-04 20:40:39Z sam $ */ 71 72#ifndef _I386_BUS_DMA_H_ 73#define _I386_BUS_DMA_H_ 74 75/* 76 * Flags used in various bus DMA methods. 77 */ 78#define BUS_DMA_WAITOK 0x00 /* safe to sleep (pseudo-flag) */ 79#define BUS_DMA_NOWAIT 0x01 /* not safe to sleep */ 80#define BUS_DMA_ALLOCNOW 0x02 /* perform resource allocation now */ 81#define BUS_DMAMEM_NOSYNC 0x04 /* map memory to not require sync */ 82#define BUS_DMA_BUS1 0x10 /* placeholders for bus functions... */ 83#define BUS_DMA_BUS2 0x20 84#define BUS_DMA_BUS3 0x40 85#define BUS_DMA_BUS4 0x80 86 87/* Forwards needed by prototypes below. */ 88struct mbuf; 89struct uio; 90 91/* 92 * bus_dmasync_op_t 93 * 94 * Operations performed by bus_dmamap_sync(). 95 */ 96typedef enum { 97 BUS_DMASYNC_PREREAD, 98 BUS_DMASYNC_POSTREAD, 99 BUS_DMASYNC_PREWRITE, 100 BUS_DMASYNC_POSTWRITE 101} bus_dmasync_op_t; 102 103/* 104 * bus_dma_tag_t 105 * 106 * A machine-dependent opaque type describing the characteristics 107 * of how to perform DMA mappings. This structure encapsultes 108 * information concerning address and alignment restrictions, number 109 * of S/G segments, amount of data per S/G segment, etc. 110 */ 111typedef struct bus_dma_tag *bus_dma_tag_t; 112 113/* 114 * bus_dmamap_t 115 * 116 * DMA mapping instance information. 117 */ 118typedef struct bus_dmamap *bus_dmamap_t; 119 120/* 121 * bus_dma_segment_t 122 * 123 * Describes a single contiguous DMA transaction. Values 124 * are suitable for programming into DMA registers. 125 */ 126typedef struct bus_dma_segment { 127 bus_addr_t ds_addr; /* DMA address */ 128 bus_size_t ds_len; /* length of transfer */ 129} bus_dma_segment_t; 130 131/* 132 * A function that returns 1 if the address cannot be accessed by 133 * a device and 0 if it can be. 134 */ 135typedef int bus_dma_filter_t(void *, bus_addr_t); 136 137/* 138 * Allocate a device specific dma_tag encapsulating the constraints of 139 * the parent tag in addition to other restrictions specified: 140 * 141 * alignment: alignment for segments. 142 * boundary: Boundary that segments cannot cross. 143 * lowaddr: Low restricted address that cannot appear in a mapping. 144 * highaddr: High restricted address that cannot appear in a mapping. 145 * filtfunc: An optional function to further test if an address 146 * within the range of lowaddr and highaddr cannot appear 147 * in a mapping. 148 * filtfuncarg: An argument that will be passed to filtfunc in addition 149 * to the address to test. 150 * maxsize: Maximum mapping size supported by this tag. 151 * nsegments: Number of discontinuities allowed in maps. 152 * maxsegsz: Maximum size of a segment in the map. 153 * flags: Bus DMA flags. 154 * dmat: A pointer to set to a valid dma tag should the return 155 * value of this function indicate success. 156 */ 157/* XXX Should probably allow specification of alignment */ 158int bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment, 159 bus_size_t boundary, bus_addr_t lowaddr, 160 bus_addr_t highaddr, bus_dma_filter_t *filtfunc, 161 void *filtfuncarg, bus_size_t maxsize, int nsegments, 162 bus_size_t maxsegsz, int flags, bus_dma_tag_t *dmat); 163 164int bus_dma_tag_destroy(bus_dma_tag_t dmat); 165 166/* 167 * Allocate a handle for mapping from kva/uva/physical 168 * address space into bus device space. 169 */ 170int bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp); 171 172/* 173 * Destroy a handle for mapping from kva/uva/physical 174 * address space into bus device space. 175 */ 176int bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map); 177 178/* 179 * Allocate a piece of memory that can be efficiently mapped into 180 * bus device space based on the constraints lited in the dma tag. 181 * A dmamap to for use with dmamap_load is also allocated. 182 */ 183int bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags, 184 bus_dmamap_t *mapp); 185 186/* 187 * Free a piece of memory and it's allociated dmamap, that was allocated 188 * via bus_dmamem_alloc. 189 */ 190void bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map); 191 192/* 193 * A function that processes a successfully loaded dma map or an error 194 * from a delayed load map. 195 */ 196typedef void bus_dmamap_callback_t(void *, bus_dma_segment_t *, int, int); 197 198/* 199 * Map the buffer buf into bus space using the dmamap map. 200 */ 201int bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf, 202 bus_size_t buflen, bus_dmamap_callback_t *callback, 203 void *callback_arg, int flags); 204 205/* 206 * Like bus_dmamap_callback but includes map size in bytes. This is 207 * defined as a separate interface to maintain compatiiblity for users 208 * of bus_dmamap_callback_t--at some point these interfaces should be merged. 209 */ 210typedef void bus_dmamap_callback2_t(void *, bus_dma_segment_t *, int, bus_size_t, int); 211/* 212 * Like bus_dmamap_load but for mbufs. Note the use of the 213 * bus_dmamap_callback2_t interface. 214 */ 215int bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, 216 struct mbuf *mbuf, 217 bus_dmamap_callback2_t *callback, void *callback_arg, 218 int flags); 219/* 220 * Like bus_dmamap_load but for uios. Note the use of the 221 * bus_dmamap_callback2_t interface. 222 */ 223int bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, 224 struct uio *ui, 225 bus_dmamap_callback2_t *callback, void *callback_arg, 226 int flags); 227 228/* 229 * Perform a syncronization operation on the given map. 230 */ 231void _bus_dmamap_sync(bus_dma_tag_t, bus_dmamap_t, bus_dmasync_op_t); 232#define bus_dmamap_sync(dmat, dmamap, op) \ 233 if ((dmamap) != NULL) \ 234 _bus_dmamap_sync(dmat, dmamap, op) 235 236/* 237 * Release the mapping held by map. 238 */ 239void _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map); 240#define bus_dmamap_unload(dmat, dmamap) \ 241 if ((dmamap) != NULL) \ 242 _bus_dmamap_unload(dmat, dmamap) 243 244#endif /* _I386_BUS_DMA_H_ */ 245