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
24/**
25 * \file drm_pci.h
26 * \brief PCI consistent, DMA-accessible memory allocation.
27 *
28 * \author Eric Anholt <anholt@FreeBSD.org>
29 */
30
31#include "drmP.h"
32
33/**********************************************************************/
34/** \name PCI memory */
35/*@{*/
36
37#if defined(__FreeBSD__)
38static void
39drm_pci_busdma_callback(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
40{
41	drm_dma_handle_t *dmah = arg;
42
43	if (error != 0)
44		return;
45
46	KASSERT(nsegs == 1, ("drm_pci_busdma_callback: bad dma segment count"));
47	dmah->busaddr = segs[0].ds_addr;
48}
49#endif
50
51/**
52 * \brief Allocate a physically contiguous DMA-accessible consistent
53 * memory block.
54 */
55drm_dma_handle_t *
56drm_pci_alloc(struct drm_device *dev, size_t size,
57	      size_t align, dma_addr_t maxaddr)
58{
59	drm_dma_handle_t *dmah;
60	int ret;
61#if defined (__NetBSD__)
62	int nsegs;
63#endif
64
65	/* Need power-of-two alignment, so fail the allocation if it isn't. */
66	if ((align & (align - 1)) != 0) {
67		DRM_ERROR("drm_pci_alloc with non-power-of-two alignment %d\n",
68		    (int)align);
69		return NULL;
70	}
71
72	dmah = malloc(sizeof(drm_dma_handle_t), DRM_MEM_DMA, M_ZERO | M_NOWAIT);
73	if (dmah == NULL)
74		return NULL;
75
76#if defined__FreeBSD__
77	/* Make sure we aren't holding locks here */
78	mtx_assert(&dev->dev_lock, MA_NOTOWNED);
79	if (mtx_owned(&dev->dev_lock))
80	    DRM_ERROR("called while holding dev_lock\n");
81	mtx_assert(&dev->dma_lock, MA_NOTOWNED);
82	if (mtx_owned(&dev->dma_lock))
83	    DRM_ERROR("called while holding dma_lock\n");
84
85	ret = bus_dma_tag_create(NULL, align, 0, /* tag, align, boundary */
86	    maxaddr, BUS_SPACE_MAXADDR, /* lowaddr, highaddr */
87	    NULL, NULL, /* filtfunc, filtfuncargs */
88	    size, 1, size, /* maxsize, nsegs, maxsegsize */
89	    0, NULL, NULL, /* flags, lockfunc, lockfuncargs */
90	    &dmah->tag);
91	if (ret != 0) {
92		free(dmah, DRM_MEM_DMA);
93		return NULL;
94	}
95
96	ret = bus_dmamem_alloc(dmah->tag, &dmah->vaddr,
97	    BUS_DMA_WAITOK | BUS_DMA_ZERO, &dmah->map);
98	if (ret != 0) {
99		bus_dma_tag_destroy(dmah->tag);
100		free(dmah, DRM_MEM_DMA);
101		return NULL;
102	}
103
104	ret = bus_dmamap_load(dmah->tag, dmah->map, dmah->vaddr, size,
105	    drm_pci_busdma_callback, dmah, BUS_DMA_NOWAIT | BUS_DMA_NOCACHE);
106	if (ret != 0) {
107		bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map);
108		bus_dma_tag_destroy(dmah->tag);
109		free(dmah, DRM_MEM_DMA);
110		return NULL;
111	}
112#elif   defined(__NetBSD__)
113	KASSERT(maxaddr >= 0xffffffffUL); /* no way to tell bus_dma_alloc */
114	dmah->tag = dev->pa.pa_dmat; /* use 32-bit DMA tag */
115
116	if ((ret = bus_dmamem_alloc(dmah->tag, size, align, 0,
117	    dmah->segs, 1, &nsegs, BUS_DMA_WAITOK)) != 0) {
118		printf("drm: Unable to allocate %zu bytes of DMA, error %d\n",
119		    size, ret);
120		dmah->tag = NULL;
121		free(dmah, DRM_MEM_DMA);
122		return NULL;
123	}
124	/* XXX is there a better way to deal with this? */
125	if (nsegs != 1) {
126		printf("drm: bad segment count from bus_dmamem_alloc\n");
127		bus_dmamem_free(dmah->tag, dmah->segs, 1);
128		dmah->tag = NULL;
129		free(dmah, DRM_MEM_DMA);
130		return NULL;
131	}
132	if ((ret = bus_dmamem_map(dmah->tag, dmah->segs, nsegs, size,
133	     &dmah->vaddr, BUS_DMA_NOWAIT | BUS_DMA_COHERENT | BUS_DMA_NOCACHE)) != 0) {
134		printf("drm: Unable to map DMA, error %d\n", ret);
135		bus_dmamem_free(dmah->tag, dmah->segs, 1);
136		dmah->tag = NULL;
137		free(dmah, DRM_MEM_DMA);
138		return NULL;
139	}
140	if ((ret = bus_dmamap_create(dmah->tag, size, 1, size, 0,
141	     BUS_DMA_NOWAIT, &dmah->map)) != 0) {
142		printf("drm: Unable to create DMA map, error %d\n", ret);
143		bus_dmamem_unmap(dmah->tag, dmah->vaddr, size);
144		bus_dmamem_free(dmah->tag, dmah->segs, 1);
145		dmah->tag = NULL;
146		free(dmah, DRM_MEM_DMA);
147		return NULL;
148	}
149	if ((ret = bus_dmamap_load(dmah->tag, dmah->map, dmah->vaddr,
150	     size, NULL, BUS_DMA_NOWAIT | BUS_DMA_NOCACHE)) != 0) {
151		printf("drm: Unable to load DMA map, error %d\n", ret);
152		bus_dmamap_destroy(dmah->tag, dmah->map);
153		bus_dmamem_unmap(dmah->tag, dmah->vaddr, size);
154		bus_dmamem_free(dmah->tag, dmah->segs, 1);
155		dmah->tag = NULL;
156		free(dmah, DRM_MEM_DMA);
157		return NULL;
158	}
159	dmah->busaddr = dmah->map->dm_segs[0].ds_addr;
160	dmah->size = size;
161	dmah->nsegs = 1;
162	memset(dmah->vaddr, 0, size);
163#endif
164
165	return dmah;
166}
167
168/**
169 * \brief Free a DMA-accessible consistent memory block.
170 */
171void
172drm_pci_free(struct drm_device *dev, drm_dma_handle_t *dmah)
173{
174	if (dmah == NULL)
175		return;
176
177#if defined(__FreeBSD__)
178	bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map);
179	bus_dma_tag_destroy(dmah->tag);
180#elif   defined(__NetBSD__)
181	bus_dmamap_unload(dmah->tag, dmah->map);
182	bus_dmamap_destroy(dmah->tag, dmah->map);
183	bus_dmamem_unmap(dmah->tag, dmah->vaddr, dmah->size);
184	bus_dmamem_free(dmah->tag, dmah->segs, 1);
185	dmah->tag = NULL;
186#endif
187
188	free(dmah, DRM_MEM_DMA);
189}
190
191/*@}*/
192