1 /* $NetBSD: bus.h,v 1.12 1997/10/01 08:25:15 fvdl Exp $ */
4 * Copyright (c) 1996, 1997 The NetBSD Foundation, Inc.
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.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
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.
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.
41 * Copyright (c) 1996 Charles M. Hannum. All rights reserved.
42 * Copyright (c) 1996 Christopher G. Demetriou. All rights reserved.
44 * Redistribution and use in source and binary forms, with or without
45 * modification, are permitted provided that the following conditions
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
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.
72 #ifndef _I386_BUS_DMA_H_
73 #define _I386_BUS_DMA_H_
76 * Flags used in various bus DMA methods.
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
87 /* Forwards needed by prototypes below. */
94 * Operations performed by bus_dmamap_sync().
100 BUS_DMASYNC_POSTWRITE
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.
111 typedef struct bus_dma_tag *bus_dma_tag_t;
116 * DMA mapping instance information.
118 typedef struct bus_dmamap *bus_dmamap_t;
123 * Describes a single contiguous DMA transaction. Values
124 * are suitable for programming into DMA registers.
126 typedef struct bus_dma_segment {
127 bus_addr_t ds_addr; /* DMA address */
128 bus_size_t ds_len; /* length of transfer */
132 * A function that returns 1 if the address cannot be accessed by
133 * a device and 0 if it can be.
135 typedef int bus_dma_filter_t(void *, bus_addr_t);
138 * Allocate a device specific dma_tag encapsulating the constraints of
139 * the parent tag in addition to other restrictions specified:
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
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.
157 /* XXX Should probably allow specification of alignment */
158 int 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);
164 int bus_dma_tag_destroy(bus_dma_tag_t dmat);
167 * Allocate a handle for mapping from kva/uva/physical
168 * address space into bus device space.
170 int bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp);
173 * Destroy a handle for mapping from kva/uva/physical
174 * address space into bus device space.
176 int bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map);
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.
183 int bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
187 * Free a piece of memory and it's allociated dmamap, that was allocated
188 * via bus_dmamem_alloc.
190 void bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map);
193 * A function that processes a successfully loaded dma map or an error
194 * from a delayed load map.
196 typedef void bus_dmamap_callback_t(void *, bus_dma_segment_t *, int, int);
199 * Map the buffer buf into bus space using the dmamap map.
201 int 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);
206 * Perform a syncronization operation on the given map.
208 void _bus_dmamap_sync(bus_dma_tag_t, bus_dmamap_t, bus_dmasync_op_t);
209 #define bus_dmamap_sync(dmat, dmamap, op) \
210 if ((dmamap) != NULL) \
211 _bus_dmamap_sync(dmat, dmamap, op)
214 * Release the mapping held by map.
216 void _bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map);
217 #define bus_dmamap_unload(dmat, dmamap) \
218 if ((dmamap) != NULL) \
219 _bus_dmamap_unload(dmat, dmamap)
221 #endif /* _I386_BUS_DMA_H_ */