xref: /dragonfly/sys/kern/subr_busdma.c (revision f9993810)
1 /*
2  * Copyright (c) 2009 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Sepherosa Ziehau <sepherosa@gmail.com>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
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
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/bus_dma.h>
38 #include <sys/mbuf.h>
39 #include <sys/malloc.h>
40 
41 static void
42 _bus_dmamem_coherent_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error)
43 {
44 	bus_addr_t *addr = arg;
45 
46 	if (error)
47 		return;
48 
49 	KASSERT(nseg == 1, ("too many DMA segments, %d should be 1", nseg));
50 	*addr = segs->ds_addr;
51 }
52 
53 int
54 bus_dmamem_coherent(bus_dma_tag_t parent,
55 		    bus_size_t alignment, bus_size_t boundary,
56 		    bus_addr_t lowaddr, bus_addr_t highaddr,
57 		    bus_size_t maxsize, int flags,
58 		    bus_dmamem_t *dmem)
59 {
60 	int error;
61 
62 	bzero(dmem, sizeof(*dmem));
63 
64 	error = bus_dma_tag_create(parent, alignment, boundary,
65 				   lowaddr, highaddr,
66 				   maxsize, 1, maxsize, 0,
67 				   &dmem->dmem_tag);
68 	if (error)
69 		return error;
70 
71         error = bus_dmamem_alloc(dmem->dmem_tag, &dmem->dmem_addr,
72 				 flags | BUS_DMA_COHERENT, &dmem->dmem_map);
73         if (error) {
74 		bus_dma_tag_destroy(dmem->dmem_tag);
75 		bzero(dmem, sizeof(*dmem));
76                 return error;
77 	}
78 
79 	error = bus_dmamap_load(dmem->dmem_tag, dmem->dmem_map,
80 				dmem->dmem_addr, maxsize,
81 				_bus_dmamem_coherent_cb, &dmem->dmem_busaddr,
82 				flags & BUS_DMA_NOWAIT);
83 	if (error) {
84 		if (error == EINPROGRESS) {
85 			panic("DMA coherent memory loading is still "
86 			      "in progress\n");
87 		}
88 		bus_dmamem_free(dmem->dmem_tag, dmem->dmem_addr,
89 				dmem->dmem_map);
90 		bus_dma_tag_destroy(dmem->dmem_tag);
91 		bzero(dmem, sizeof(*dmem));
92 		return error;
93 	}
94 	return 0;
95 }
96 
97 void *
98 bus_dmamem_coherent_any(bus_dma_tag_t parent,
99 			bus_size_t alignment, bus_size_t size, int flags,
100 			bus_dma_tag_t *dtag, bus_dmamap_t *dmap,
101 			bus_addr_t *busaddr)
102 {
103 	bus_dmamem_t dmem;
104 	int error;
105 
106 	error = bus_dmamem_coherent(parent, alignment, 0,
107 				    BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR,
108 				    size, flags, &dmem);
109 	if (error)
110 		return NULL;
111 
112 	*dtag = dmem.dmem_tag;
113 	*dmap = dmem.dmem_map;
114 	*busaddr = dmem.dmem_busaddr;
115 
116 	return dmem.dmem_addr;
117 }
118 
119 int
120 bus_dmamap_load_mbuf_defrag(bus_dma_tag_t dmat, bus_dmamap_t map,
121 			    struct mbuf **m_head,
122 			    bus_dma_segment_t *segs, int maxsegs,
123 			    int *nsegs, int flags)
124 {
125 	struct mbuf *m = *m_head;
126 	int error;
127 
128 	error = bus_dmamap_load_mbuf_segment(dmat, map, m,
129 			segs, maxsegs, nsegs, flags);
130 	if (error == EFBIG) {
131 		struct mbuf *m_new;
132 
133 		m_new = m_defrag(m, M_NOWAIT);
134 		if (m_new == NULL)
135 			return ENOBUFS;
136 		else
137 			*m_head = m = m_new;
138 
139 		error = bus_dmamap_load_mbuf_segment(dmat, map, m,
140 				segs, maxsegs, nsegs, flags);
141 	}
142 	return error;
143 }
144