xref: /freebsd/sys/dev/drm2/drm_scatter.c (revision 313376588638950ba1e93c403dd8c97bc52fd3a2)
1 /*-
2  * Copyright (c) 2009 Robert C. Noland III <rnoland@FreeBSD.org>
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
19  * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
22  * DEALINGS IN THE SOFTWARE.
23  */
24 
25 #include <sys/cdefs.h>
26 __FBSDID("$FreeBSD$");
27 
28 /** @file drm_scatter.c
29  * Allocation of memory for scatter-gather mappings by the graphics chip.
30  * The memory allocated here is then made into an aperture in the card
31  * by mapping the pages into the GART.
32  */
33 
34 #include <dev/drm2/drmP.h>
35 
36 int
37 drm_sg_alloc(struct drm_device *dev, struct drm_scatter_gather *request)
38 {
39 	struct drm_sg_mem *entry;
40 	vm_size_t size;
41 	vm_pindex_t pindex;
42 
43 	if (dev->sg)
44 		return EINVAL;
45 
46 	DRM_DEBUG("request size=%ld\n", request->size);
47 
48 	entry = malloc(sizeof(*entry), DRM_MEM_DRIVER, M_WAITOK | M_ZERO);
49 
50 	size = round_page(request->size);
51 	entry->pages = OFF_TO_IDX(size);
52 	entry->busaddr = malloc(entry->pages * sizeof(*entry->busaddr),
53 	    DRM_MEM_SGLISTS, M_WAITOK | M_ZERO);
54 
55 	entry->vaddr = kmem_alloc_attr(kernel_arena, size, M_WAITOK | M_ZERO,
56 	    0, BUS_SPACE_MAXADDR_32BIT, VM_MEMATTR_WRITE_COMBINING);
57 	if (entry->vaddr == 0) {
58 		drm_sg_cleanup(entry);
59 		return (ENOMEM);
60 	}
61 
62 	for(pindex = 0; pindex < entry->pages; pindex++) {
63 		entry->busaddr[pindex] =
64 		    vtophys(entry->vaddr + IDX_TO_OFF(pindex));
65 	}
66 
67 	DRM_LOCK(dev);
68 	if (dev->sg) {
69 		DRM_UNLOCK(dev);
70 		drm_sg_cleanup(entry);
71 		return (EINVAL);
72 	}
73 	dev->sg = entry;
74 	DRM_UNLOCK(dev);
75 
76 	request->handle = entry->vaddr;
77 
78 	DRM_DEBUG("allocated %ju pages @ 0x%08zx, contents=%08lx\n",
79 	    entry->pages, entry->vaddr, *(unsigned long *)entry->vaddr);
80 
81 	return (0);
82 }
83 
84 int
85 drm_sg_alloc_ioctl(struct drm_device *dev, void *data,
86 		   struct drm_file *file_priv)
87 {
88 	struct drm_scatter_gather *request = data;
89 
90 	DRM_DEBUG("\n");
91 
92 	return (drm_sg_alloc(dev, request));
93 }
94 
95 void
96 drm_sg_cleanup(struct drm_sg_mem *entry)
97 {
98 	if (entry == NULL)
99 		return;
100 
101 	if (entry->vaddr != 0)
102 		kmem_free(kernel_arena, entry->vaddr, IDX_TO_OFF(entry->pages));
103 
104 	free(entry->busaddr, DRM_MEM_SGLISTS);
105 	free(entry, DRM_MEM_DRIVER);
106 
107 	return;
108 }
109 
110 int
111 drm_sg_free(struct drm_device *dev, void *data, struct drm_file *file_priv)
112 {
113 	struct drm_scatter_gather *request = data;
114 	struct drm_sg_mem *entry;
115 
116 	DRM_LOCK(dev);
117 	entry = dev->sg;
118 	dev->sg = NULL;
119 	DRM_UNLOCK(dev);
120 
121 	if (!entry || entry->vaddr != request->handle)
122 		return (EINVAL);
123 
124 	DRM_DEBUG("free 0x%zx\n", entry->vaddr);
125 
126 	drm_sg_cleanup(entry);
127 
128 	return (0);
129 }
130