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#include <sys/cdefs.h>
25__FBSDID("$FreeBSD$");
26
27/**
28 * \file drm_pci.h
29 * \brief PCI consistent, DMA-accessible memory allocation.
30 *
31 * \author Eric Anholt <anholt@FreeBSD.org>
32 */
33
34#include "dev/drm/drmP.h"
35
36/**********************************************************************/
37/** \name PCI memory */
38/*@{*/
39
40static void
41drm_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
52/**
53 * \brief Allocate a physically contiguous DMA-accessible consistent
54 * memory block.
55 */
56drm_dma_handle_t *
57drm_pci_alloc(struct drm_device *dev, size_t size,
58	      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), DRM_MEM_DMA, M_ZERO | M_NOWAIT);
71	if (dmah == NULL)
72		return NULL;
73
74	/* Make sure we aren't holding locks here */
75	mtx_assert(&dev->dev_lock, MA_NOTOWNED);
76	if (mtx_owned(&dev->dev_lock))
77	    DRM_ERROR("called while holding dev_lock\n");
78	mtx_assert(&dev->dma_lock, MA_NOTOWNED);
79	if (mtx_owned(&dev->dma_lock))
80	    DRM_ERROR("called while holding dma_lock\n");
81
82	ret = bus_dma_tag_create(NULL, align, 0, /* tag, align, boundary */
83	    maxaddr, BUS_SPACE_MAXADDR, /* lowaddr, highaddr */
84	    NULL, NULL, /* filtfunc, filtfuncargs */
85	    size, 1, size, /* maxsize, nsegs, maxsegsize */
86	    0, NULL, NULL, /* flags, lockfunc, lockfuncargs */
87	    &dmah->tag);
88	if (ret != 0) {
89		free(dmah, DRM_MEM_DMA);
90		return NULL;
91	}
92
93	ret = bus_dmamem_alloc(dmah->tag, &dmah->vaddr,
94	    BUS_DMA_WAITOK | BUS_DMA_ZERO | BUS_DMA_NOCACHE, &dmah->map);
95	if (ret != 0) {
96		bus_dma_tag_destroy(dmah->tag);
97		free(dmah, DRM_MEM_DMA);
98		return NULL;
99	}
100
101	ret = bus_dmamap_load(dmah->tag, dmah->map, dmah->vaddr, size,
102	    drm_pci_busdma_callback, dmah, BUS_DMA_NOWAIT);
103	if (ret != 0) {
104		bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map);
105		bus_dma_tag_destroy(dmah->tag);
106		free(dmah, DRM_MEM_DMA);
107		return NULL;
108	}
109
110	return dmah;
111}
112
113/**
114 * \brief Free a DMA-accessible consistent memory block.
115 */
116void
117drm_pci_free(struct drm_device *dev, drm_dma_handle_t *dmah)
118{
119	if (dmah == NULL)
120		return;
121
122	bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map);
123	bus_dma_tag_destroy(dmah->tag);
124
125	free(dmah, DRM_MEM_DMA);
126}
127
128/*@}*/
129