airport: remove useless return in a function returning void
[linux/fpc-iii.git] / drivers / gpu / drm / drm_memory.c
blob803bc9e7ce3c8639f026d3479b5ec2217a84802d
1 /**
2 * \file drm_memory.c
3 * Memory management wrappers for DRM
5 * \author Rickard E. (Rik) Faith <faith@valinux.com>
6 * \author Gareth Hughes <gareth@valinux.com>
7 */
9 /*
10 * Created: Thu Feb 4 14:00:34 1999 by faith@valinux.com
12 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
13 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
14 * All Rights Reserved.
16 * Permission is hereby granted, free of charge, to any person obtaining a
17 * copy of this software and associated documentation files (the "Software"),
18 * to deal in the Software without restriction, including without limitation
19 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
20 * and/or sell copies of the Software, and to permit persons to whom the
21 * Software is furnished to do so, subject to the following conditions:
23 * The above copyright notice and this permission notice (including the next
24 * paragraph) shall be included in all copies or substantial portions of the
25 * Software.
27 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
28 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
29 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
30 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
31 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
32 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
33 * OTHER DEALINGS IN THE SOFTWARE.
36 #include <linux/highmem.h>
37 #include "drmP.h"
39 #ifdef DEBUG_MEMORY
40 #include "drm_memory_debug.h"
41 #else
43 /** No-op. */
44 void drm_mem_init(void)
48 /**
49 * Called when "/proc/dri/%dev%/mem" is read.
51 * \param buf output buffer.
52 * \param start start of output data.
53 * \param offset requested start offset.
54 * \param len requested number of bytes.
55 * \param eof whether there is no more data to return.
56 * \param data private data.
57 * \return number of written bytes.
59 * No-op.
61 int drm_mem_info(char *buf, char **start, off_t offset,
62 int len, int *eof, void *data)
64 return 0;
67 /** Wrapper around kmalloc() and kfree() */
68 void *drm_realloc(void *oldpt, size_t oldsize, size_t size, int area)
70 void *pt;
72 if (!(pt = kmalloc(size, GFP_KERNEL)))
73 return NULL;
74 if (oldpt && oldsize) {
75 memcpy(pt, oldpt, oldsize);
76 kfree(oldpt);
78 return pt;
81 #if __OS_HAS_AGP
82 static void *agp_remap(unsigned long offset, unsigned long size,
83 struct drm_device * dev)
85 unsigned long *phys_addr_map, i, num_pages =
86 PAGE_ALIGN(size) / PAGE_SIZE;
87 struct drm_agp_mem *agpmem;
88 struct page **page_map;
89 void *addr;
91 size = PAGE_ALIGN(size);
93 #ifdef __alpha__
94 offset -= dev->hose->mem_space->start;
95 #endif
97 list_for_each_entry(agpmem, &dev->agp->memory, head)
98 if (agpmem->bound <= offset
99 && (agpmem->bound + (agpmem->pages << PAGE_SHIFT)) >=
100 (offset + size))
101 break;
102 if (!agpmem)
103 return NULL;
106 * OK, we're mapping AGP space on a chipset/platform on which memory accesses by
107 * the CPU do not get remapped by the GART. We fix this by using the kernel's
108 * page-table instead (that's probably faster anyhow...).
110 /* note: use vmalloc() because num_pages could be large... */
111 page_map = vmalloc(num_pages * sizeof(struct page *));
112 if (!page_map)
113 return NULL;
115 phys_addr_map =
116 agpmem->memory->memory + (offset - agpmem->bound) / PAGE_SIZE;
117 for (i = 0; i < num_pages; ++i)
118 page_map[i] = pfn_to_page(phys_addr_map[i] >> PAGE_SHIFT);
119 addr = vmap(page_map, num_pages, VM_IOREMAP, PAGE_AGP);
120 vfree(page_map);
122 return addr;
125 /** Wrapper around agp_allocate_memory() */
126 DRM_AGP_MEM *drm_alloc_agp(struct drm_device * dev, int pages, u32 type)
128 return drm_agp_allocate_memory(dev->agp->bridge, pages, type);
131 /** Wrapper around agp_free_memory() */
132 int drm_free_agp(DRM_AGP_MEM * handle, int pages)
134 return drm_agp_free_memory(handle) ? 0 : -EINVAL;
136 EXPORT_SYMBOL(drm_free_agp);
138 /** Wrapper around agp_bind_memory() */
139 int drm_bind_agp(DRM_AGP_MEM * handle, unsigned int start)
141 return drm_agp_bind_memory(handle, start);
144 /** Wrapper around agp_unbind_memory() */
145 int drm_unbind_agp(DRM_AGP_MEM * handle)
147 return drm_agp_unbind_memory(handle);
149 EXPORT_SYMBOL(drm_unbind_agp);
151 #else /* __OS_HAS_AGP */
152 static inline void *agp_remap(unsigned long offset, unsigned long size,
153 struct drm_device * dev)
155 return NULL;
158 #endif /* agp */
160 #endif /* debug_memory */
162 void drm_core_ioremap(struct drm_map *map, struct drm_device *dev)
164 if (drm_core_has_AGP(dev) &&
165 dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
166 map->handle = agp_remap(map->offset, map->size, dev);
167 else
168 map->handle = ioremap(map->offset, map->size);
170 EXPORT_SYMBOL(drm_core_ioremap);
172 void drm_core_ioremap_wc(struct drm_map *map, struct drm_device *dev)
174 map->handle = ioremap_wc(map->offset, map->size);
176 EXPORT_SYMBOL(drm_core_ioremap_wc);
177 void drm_core_ioremapfree(struct drm_map *map, struct drm_device *dev)
179 if (!map->handle || !map->size)
180 return;
182 if (drm_core_has_AGP(dev) &&
183 dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
184 vunmap(map->handle);
185 else
186 iounmap(map->handle);
188 EXPORT_SYMBOL(drm_core_ioremapfree);