drm_pci.c revision 152909 
1/**
2 * \file drm_pci.h
3 * \brief PCI consistent, DMA-accessible memory functions.
4 *
5 * \author Eric Anholt <anholt@FreeBSD.org>
6 */
7
8/*-
9 * Copyright 2003 Eric Anholt.
10 * All Rights Reserved.
11 *
12 * Permission is hereby granted, free of charge, to any person obtaining a
13 * copy of this software and associated documentation files (the "Software"),
14 * to deal in the Software without restriction, including without limitation
15 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
16 * and/or sell copies of the Software, and to permit persons to whom the
17 * Software is furnished to do so, subject to the following conditions:
18 *
19 * The above copyright notice and this permission notice (including the next
20 * paragraph) shall be included in all copies or substantial portions of the
21 * Software.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
24 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
25 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
26 * AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
27 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
28 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
29 */
30
31#include <sys/cdefs.h>
32__FBSDID("$FreeBSD: head/sys/dev/drm/drm_pci.c 152909 2005-11-28 23:13:57Z anholt $");
33
34#include "dev/drm/drmP.h"
35
36/**********************************************************************/
37/** \name PCI memory */
38/*@{*/
39
40#if defined(__FreeBSD__)
41static void
42drm_pci_busdma_callback(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
43{
44	drm_dma_handle_t *dmah = arg;
45
46	if (error != 0)
47		return;
48
49	KASSERT(nsegs == 1, ("drm_pci_busdma_callback: bad dma segment count"));
50	dmah->busaddr = segs[0].ds_addr;
51}
52#endif
53
54/**
55 * \brief Allocate a physically contiguous DMA-accessible consistent
56 * memory block.
57 */
58drm_dma_handle_t *
59drm_pci_alloc(drm_device_t *dev, size_t size, size_t align, dma_addr_t maxaddr)
60{
61	drm_dma_handle_t *dmah;
62	int ret;
63
64	/* Need power-of-two alignment, so fail the allocation if it isn't. */
65	if ((align & (align - 1)) != 0) {
66		DRM_ERROR("drm_pci_alloc with non-power-of-two alignment %d\n",
67		    (int)align);
68		return NULL;
69	}
70
71	dmah = malloc(sizeof(drm_dma_handle_t), M_DRM, M_ZERO | M_NOWAIT);
72	if (dmah == NULL)
73		return NULL;
74
75#ifdef __FreeBSD__
76	ret = bus_dma_tag_create(NULL, align, 0, /* tag, align, boundary */
77	    maxaddr, BUS_SPACE_MAXADDR, /* lowaddr, highaddr */
78	    NULL, NULL, /* filtfunc, filtfuncargs */
79	    size, 1, size, /* maxsize, nsegs, maxsegsize */
80	    BUS_DMA_ALLOCNOW, NULL, NULL, /* flags, lockfunc, lockfuncargs */
81	    &dmah->tag);
82	if (ret != 0) {
83		free(dmah, M_DRM);
84		return NULL;
85	}
86
87	ret = bus_dmamem_alloc(dmah->tag, &dmah->vaddr, BUS_DMA_NOWAIT,
88	    &dmah->map);
89	if (ret != 0) {
90		bus_dma_tag_destroy(dmah->tag);
91		free(dmah, M_DRM);
92		return NULL;
93	}
94
95	ret = bus_dmamap_load(dmah->tag, dmah->map, dmah->vaddr, size,
96	    drm_pci_busdma_callback, dmah, 0);
97	if (ret != 0) {
98		bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map);
99		bus_dma_tag_destroy(dmah->tag);
100		free(dmah, M_DRM);
101		return NULL;
102	}
103#elif defined(__NetBSD__)
104	ret = bus_dmamem_alloc(dev->dma_tag, size, align, PAGE_SIZE,
105	    &dmah->seg, 1, &nsegs, BUS_DMA_NOWAIT);
106	if ((ret != 0) || (nsegs != 1)) {
107		free(dmah, M_DRM);
108		return NULL;
109	}
110
111	ret = bus_dmamem_map(dev->dma_tag, &dmah->seg, 1, size, &dmah->addr,
112	    BUS_DMA_NOWAIT);
113	if (ret != 0) {
114		bus_dmamem_free(dev->dma_tag, &dmah->seg, 1);
115		free(dmah, M_DRM);
116		return NULL;
117	}
118
119	dmah->dmaaddr = h->seg.ds_addr;
120#endif
121
122	return dmah;
123}
124
125/**
126 * \brief Free a DMA-accessible consistent memory block.
127 */
128void
129drm_pci_free(drm_device_t *dev, drm_dma_handle_t *dmah)
130{
131	if (dmah == NULL)
132		return;
133
134#if defined(__FreeBSD__)
135	bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map);
136	bus_dma_tag_destroy(dmah->tag);
137#elif defined(__NetBSD__)
138	bus_dmamem_free(dev->dma_tag, &dmah->seg, 1);
139#endif
140
141	free(dmah, M_DRM);
142}
143
144/*@}*/
145