LXR linux/drivers/gpu/drm/drm

   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 "drmP.h"
  39
  40/**
  41 * Called when "/proc/dri/%dev%/mem" is read.
  42 *
  43 * \param buf output buffer.
  44 * \param start start of output data.
  45 * \param offset requested start offset.
  46 * \param len requested number of bytes.
  47 * \param eof whether there is no more data to return.
  48 * \param data private data.
  49 * \return number of written bytes.
  50 *
  51 * No-op.
  52 */
  53int drm_mem_info(char *buf, char **start, off_t offset,
  54                 int len, int *eof, void *data)
  55{
  56        return 0;
  57}
  58
  59#if __OS_HAS_AGP
  60static void *agp_remap(unsigned long offset, unsigned long size,
  61                       struct drm_device * dev)
  62{
  63        unsigned long i, num_pages =
  64            PAGE_ALIGN(size) / PAGE_SIZE;
  65        struct drm_agp_mem *agpmem;
  66        struct page **page_map;
  67        struct page **phys_page_map;
  68        void *addr;
  69
  70        size = PAGE_ALIGN(size);
  71
  72#ifdef __alpha__
  73        offset -= dev->hose->mem_space->start;
  74#endif
  75
  76        list_for_each_entry(agpmem, &dev->agp->memory, head)
  77                if (agpmem->bound <= offset
  78                    && (agpmem->bound + (agpmem->pages << PAGE_SHIFT)) >=
  79                    (offset + size))
  80                        break;
  81        if (&agpmem->head == &dev->agp->memory)
  82                return NULL;
  83
  84        /*
  85         * OK, we're mapping AGP space on a chipset/platform on which memory accesses by
  86         * the CPU do not get remapped by the GART.  We fix this by using the kernel's
  87         * page-table instead (that's probably faster anyhow...).
  88         */
  89        /* note: use vmalloc() because num_pages could be large... */
  90        page_map = vmalloc(num_pages * sizeof(struct page *));
  91        if (!page_map)
  92                return NULL;
  93
  94        phys_page_map = (agpmem->memory->pages + (offset - agpmem->bound) / PAGE_SIZE);
  95        for (i = 0; i < num_pages; ++i)
  96                page_map[i] = phys_page_map[i];
  97        addr = vmap(page_map, num_pages, VM_IOREMAP, PAGE_AGP);
  98        vfree(page_map);
  99
 100        return addr;
 101}
 102
 103/** Wrapper around agp_free_memory() */
 104void drm_free_agp(DRM_AGP_MEM * handle, int pages)
 105{
 106        agp_free_memory(handle);
 107}
 108EXPORT_SYMBOL(drm_free_agp);
 109
 110/** Wrapper around agp_bind_memory() */
 111int drm_bind_agp(DRM_AGP_MEM * handle, unsigned int start)
 112{
 113        return agp_bind_memory(handle, start);
 114}
 115
 116/** Wrapper around agp_unbind_memory() */
 117int drm_unbind_agp(DRM_AGP_MEM * handle)
 118{
 119        return agp_unbind_memory(handle);
 120}
 121EXPORT_SYMBOL(drm_unbind_agp);
 122
 123#else  /*  __OS_HAS_AGP  */
 124static inline void *agp_remap(unsigned long offset, unsigned long size,
 125                              struct drm_device * dev)
 126{
 127        return NULL;
 128}
 129
 130#endif                          /* agp */
 131
 132void drm_core_ioremap(struct drm_local_map *map, struct drm_device *dev)
 133{
 134        if (drm_core_has_AGP(dev) &&
 135            dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
 136                map->handle = agp_remap(map->offset, map->size, dev);
 137        else
 138                map->handle = ioremap(map->offset, map->size);
 139}
 140EXPORT_SYMBOL(drm_core_ioremap);
 141
 142void drm_core_ioremap_wc(struct drm_local_map *map, struct drm_device *dev)
 143{
 144        if (drm_core_has_AGP(dev) &&
 145            dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
 146                map->handle = agp_remap(map->offset, map->size, dev);
 147        else
 148                map->handle = ioremap_wc(map->offset, map->size);
 149}
 150EXPORT_SYMBOL(drm_core_ioremap_wc);
 151
 152void drm_core_ioremapfree(struct drm_local_map *map, struct drm_device *dev)
 153{
 154        if (!map->handle || !map->size)
 155                return;
 156
 157        if (drm_core_has_AGP(dev) &&
 158            dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
 159                vunmap(map->handle);
 160        else
 161                iounmap(map->handle);
 162}
 163EXPORT_SYMBOL(drm_core_ioremapfree);
 164