xref: /dragonfly/sys/dev/drm/drm_pci.c (revision e2f5ccfb)
1 /*-
2  * Copyright 2003 Eric Anholt.
3  * All Rights Reserved.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice (including the next
13  * paragraph) shall be included in all copies or substantial portions of the
14  * Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
19  * AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
21  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22  *
23  * $DragonFly: src/sys/dev/drm/drm_pci.c,v 1.1 2008/04/05 18:12:29 hasso Exp $
24  */
25 
26 /**
27  * \file drm_pci.h
28  * \brief PCI consistent, DMA-accessible memory allocation.
29  *
30  * \author Eric Anholt <anholt@FreeBSD.org>
31  */
32 
33 #include "drmP.h"
34 
35 /**********************************************************************/
36 /** \name PCI memory */
37 /*@{*/
38 
39 #if defined(__FreeBSD__) || defined(__DragonFly__)
40 static void
41 drm_pci_busdma_callback(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
42 {
43 	drm_dma_handle_t *dmah = arg;
44 
45 	if (error != 0)
46 		return;
47 
48 	KASSERT(nsegs == 1, ("drm_pci_busdma_callback: bad dma segment count"));
49 	dmah->busaddr = segs[0].ds_addr;
50 }
51 #endif
52 
53 /**
54  * \brief Allocate a physically contiguous DMA-accessible consistent
55  * memory block.
56  */
57 drm_dma_handle_t *
58 drm_pci_alloc(drm_device_t *dev, size_t size, size_t align, dma_addr_t maxaddr)
59 {
60 	drm_dma_handle_t *dmah;
61 	int ret;
62 
63 	/* Need power-of-two alignment, so fail the allocation if it isn't. */
64 	if ((align & (align - 1)) != 0) {
65 		DRM_ERROR("drm_pci_alloc with non-power-of-two alignment %d\n",
66 		    (int)align);
67 		return NULL;
68 	}
69 
70 	dmah = malloc(sizeof(drm_dma_handle_t), M_DRM, M_ZERO | M_NOWAIT);
71 	if (dmah == NULL)
72 		return NULL;
73 
74 #if defined(__FreeBSD__) || defined(__DragonFly__)
75 	ret = bus_dma_tag_create(NULL, align, 0, /* tag, align, boundary */
76 	    maxaddr, BUS_SPACE_MAXADDR, /* lowaddr, highaddr */
77 	    NULL, NULL, /* filtfunc, filtfuncargs */
78 	    size, 1, size, /* maxsize, nsegs, maxsegsize */
79 	    BUS_DMA_ALLOCNOW, /* flags */
80 #ifdef __FreeBSD__
81 	    NULL, NULL, /* lockfunc, lockfuncargs */
82 #endif
83 	    &dmah->tag);
84 	if (ret != 0) {
85 		free(dmah, M_DRM);
86 		return NULL;
87 	}
88 
89 	ret = bus_dmamem_alloc(dmah->tag, &dmah->vaddr, BUS_DMA_NOWAIT,
90 	    &dmah->map);
91 	if (ret != 0) {
92 		bus_dma_tag_destroy(dmah->tag);
93 		free(dmah, M_DRM);
94 		return NULL;
95 	}
96 
97 	ret = bus_dmamap_load(dmah->tag, dmah->map, dmah->vaddr, size,
98 	    drm_pci_busdma_callback, dmah, 0);
99 	if (ret != 0) {
100 		bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map);
101 		bus_dma_tag_destroy(dmah->tag);
102 		free(dmah, M_DRM);
103 		return NULL;
104 	}
105 #elif defined(__NetBSD__)
106 	ret = bus_dmamem_alloc(dev->dma_tag, size, align, PAGE_SIZE,
107 	    &dmah->seg, 1, &nsegs, BUS_DMA_NOWAIT);
108 	if ((ret != 0) || (nsegs != 1)) {
109 		free(dmah, M_DRM);
110 		return NULL;
111 	}
112 
113 	ret = bus_dmamem_map(dev->dma_tag, &dmah->seg, 1, size, &dmah->addr,
114 	    BUS_DMA_NOWAIT);
115 	if (ret != 0) {
116 		bus_dmamem_free(dev->dma_tag, &dmah->seg, 1);
117 		free(dmah, M_DRM);
118 		return NULL;
119 	}
120 
121 	dmah->dmaaddr = h->seg.ds_addr;
122 #endif
123 
124 	return dmah;
125 }
126 
127 /**
128  * \brief Free a DMA-accessible consistent memory block.
129  */
130 void
131 drm_pci_free(drm_device_t *dev, drm_dma_handle_t *dmah)
132 {
133 	if (dmah == NULL)
134 		return;
135 
136 #if defined(__FreeBSD__) || defined(__DragonFly__)
137 	bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map);
138 	bus_dma_tag_destroy(dmah->tag);
139 #elif defined(__NetBSD__)
140 	bus_dmamem_free(dev->dma_tag, &dmah->seg, 1);
141 #endif
142 
143 	free(dmah, M_DRM);
144 }
145 
146 /*@}*/
147