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 <linux/export.h>
  38 #include <drm/drmP.h>
  39
  40 #if __OS_HAS_AGP
  41 static void *agp_remap(unsigned long offset, unsigned long size,
  42                        struct drm_device * dev)
  43 {
  44         unsigned long i, num_pages =
  45             PAGE_ALIGN(size) / PAGE_SIZE;
  46         struct drm_agp_mem *agpmem;
  47         struct page **page_map;
  48         struct page **phys_page_map;
  49         void *addr;
  50
  51         size = PAGE_ALIGN(size);
  52
  53 #ifdef __alpha__
  54         offset -= dev->hose->mem_space->start;
  55 #endif
  56
  57         list_for_each_entry(agpmem, &dev->agp->memory, head)
  58                 if (agpmem->bound <= offset
  59                     && (agpmem->bound + (agpmem->pages << PAGE_SHIFT)) >=
  60                     (offset + size))
  61                         break;
  62         if (&agpmem->head == &dev->agp->memory)
  63                 return NULL;
  64
  65         /*
  66          * OK, we're mapping AGP space on a chipset/platform on which memory accesses by
  67          * the CPU do not get remapped by the GART.  We fix this by using the kernel's
  68          * page-table instead (that's probably faster anyhow...).
  69          */
  70         /* note: use vmalloc() because num_pages could be large... */
  71         page_map = vmalloc(num_pages * sizeof(struct page *));
  72         if (!page_map)
  73                 return NULL;
  74
  75         phys_page_map = (agpmem->memory->pages + (offset - agpmem->bound) / PAGE_SIZE);
  76         for (i = 0; i < num_pages; ++i)
  77                 page_map[i] = phys_page_map[i];
  78         addr = vmap(page_map, num_pages, VM_IOREMAP, PAGE_AGP);
  79         vfree(page_map);
  80
  81         return addr;
  82 }
  83
  84 /** Wrapper around agp_free_memory() */
  85 void drm_free_agp(struct agp_memory * handle, int pages)
  86 {
  87         agp_free_memory(handle);
  88 }
  89
  90 /** Wrapper around agp_bind_memory() */
  91 int drm_bind_agp(struct agp_memory * handle, unsigned int start)
  92 {
  93         return agp_bind_memory(handle, start);
  94 }
  95
  96 /** Wrapper around agp_unbind_memory() */
  97 int drm_unbind_agp(struct agp_memory * handle)
  98 {
  99         return agp_unbind_memory(handle);
 100 }
 101
 102 #else  /*  __OS_HAS_AGP  */
 103 static inline void *agp_remap(unsigned long offset, unsigned long size,
 104                               struct drm_device * dev)
 105 {
 106         return NULL;
 107 }
 108
 109 #endif                          /* agp */
 110
 111 void drm_core_ioremap(struct drm_local_map *map, struct drm_device *dev)
 112 {
 113         if (dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
 114                 map->handle = agp_remap(map->offset, map->size, dev);
 115         else
 116                 map->handle = ioremap(map->offset, map->size);
 117 }
 118 EXPORT_SYMBOL(drm_core_ioremap);
 119
 120 void drm_core_ioremap_wc(struct drm_local_map *map, struct drm_device *dev)
 121 {
 122         if (dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
 123                 map->handle = agp_remap(map->offset, map->size, dev);
 124         else
 125                 map->handle = ioremap_wc(map->offset, map->size);
 126 }
 127 EXPORT_SYMBOL(drm_core_ioremap_wc);
 128
 129 void drm_core_ioremapfree(struct drm_local_map *map, struct drm_device *dev)
 130 {
 131         if (!map->handle || !map->size)
 132                 return;
 133
 134         if (dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
 135                 vunmap(map->handle);
 136         else
 137                 iounmap(map->handle);
 138 }
 139 EXPORT_SYMBOL(drm_core_ioremapfree);