drivers/gpu/drm/drm_memory.c

   1 /**
   2  * \file drm_memory.c
   3  * Memory management wrappers for DRM
   4  *
   5  * \author Rickard E. (Rik) Faith <faith@valinux.com>
   6  * \author Gareth Hughes <gareth@valinux.com>
   7  */
   8
   9 /*
  10  * Created: Thu Feb  4 14:00:34 1999 by faith@valinux.com
  11  *
  12  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
  13  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
  14  * All Rights Reserved.
  15  *
  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:
  22  *
  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.
  26  *
  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.
  34  */
  35
  36 #include <linux/highmem.h>
  37 #include "drmP.h"
  38
  39 /**
  40  * Called when "/proc/dri/%dev%/mem" is read.
  41  *
  42  * \param buf output buffer.
  43  * \param start start of output data.
  44  * \param offset requested start offset.
  45  * \param len requested number of bytes.
  46  * \param eof whether there is no more data to return.
  47  * \param data private data.
  48  * \return number of written bytes.
  49  *
  50  * No-op.
  51  */
  52 int drm_mem_info(char *buf, char **start, off_t offset,
  53                  int len, int *eof, void *data)
  54 {
  55         return 0;
  56 }
  57
  58 #if __OS_HAS_AGP
  59 static void *agp_remap(unsigned long offset, unsigned long size,
  60                        struct drm_device * dev)
  61 {
  62         unsigned long i, num_pages =
  63             PAGE_ALIGN(size) / PAGE_SIZE;
  64         struct drm_agp_mem *agpmem;
  65         struct page **page_map;
  66         struct page **phys_page_map;
  67         void *addr;
  68
  69         size = PAGE_ALIGN(size);
  70
  71 #ifdef __alpha__
  72         offset -= dev->hose->mem_space->start;
  73 #endif
  74
  75         list_for_each_entry(agpmem, &dev->agp->memory, head)
  76                 if (agpmem->bound <= offset
  77                     && (agpmem->bound + (agpmem->pages << PAGE_SHIFT)) >=
  78                     (offset + size))
  79                         break;
  80         if (&agpmem->head == &dev->agp->memory)
  81                 return NULL;
  82
  83         /*
  84          * OK, we're mapping AGP space on a chipset/platform on which memory accesses by
  85          * the CPU do not get remapped by the GART.  We fix this by using the kernel's
  86          * page-table instead (that's probably faster anyhow...).
  87          */
  88         /* note: use vmalloc() because num_pages could be large... */
  89         page_map = vmalloc(num_pages * sizeof(struct page *));
  90         if (!page_map)
  91                 return NULL;
  92
  93         phys_page_map = (agpmem->memory->pages + (offset - agpmem->bound) / PAGE_SIZE);
  94         for (i = 0; i < num_pages; ++i)
  95                 page_map[i] = phys_page_map[i];
  96         addr = vmap(page_map, num_pages, VM_IOREMAP, PAGE_AGP);
  97         vfree(page_map);
  98
  99         return addr;
 100 }
 101
 102 /** Wrapper around agp_free_memory() */
 103 void drm_free_agp(DRM_AGP_MEM * handle, int pages)
 104 {
 105         agp_free_memory(handle);
 106 }
 107 EXPORT_SYMBOL(drm_free_agp);
 108
 109 /** Wrapper around agp_bind_memory() */
 110 int drm_bind_agp(DRM_AGP_MEM * handle, unsigned int start)
 111 {
 112         return agp_bind_memory(handle, start);
 113 }
 114
 115 /** Wrapper around agp_unbind_memory() */
 116 int drm_unbind_agp(DRM_AGP_MEM * handle)
 117 {
 118         return agp_unbind_memory(handle);
 119 }
 120 EXPORT_SYMBOL(drm_unbind_agp);
 121
 122 #else  /*  __OS_HAS_AGP  */
 123 static inline void *agp_remap(unsigned long offset, unsigned long size,
 124                               struct drm_device * dev)
 125 {
 126         return NULL;
 127 }
 128
 129 #endif                          /* agp */
 130
 131 void drm_core_ioremap(struct drm_local_map *map, struct drm_device *dev)
 132 {
 133         if (drm_core_has_AGP(dev) &&
 134             dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
 135                 map->handle = agp_remap(map->offset, map->size, dev);
 136         else
 137                 map->handle = ioremap(map->offset, map->size);
 138 }
 139 EXPORT_SYMBOL(drm_core_ioremap);
 140
 141 void drm_core_ioremap_wc(struct drm_local_map *map, struct drm_device *dev)
 142 {
 143         if (drm_core_has_AGP(dev) &&
 144             dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
 145                 map->handle = agp_remap(map->offset, map->size, dev);
 146         else
 147                 map->handle = ioremap_wc(map->offset, map->size);
 148 }
 149 EXPORT_SYMBOL(drm_core_ioremap_wc);
 150
 151 void drm_core_ioremapfree(struct drm_local_map *map, struct drm_device *dev)
 152 {
 153         if (!map->handle || !map->size)
 154                 return;
 155
 156         if (drm_core_has_AGP(dev) &&
 157             dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
 158                 vunmap(map->handle);
 159         else
 160                 iounmap(map->handle);
 161 }
 162 EXPORT_SYMBOL(drm_core_ioremapfree);