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