drm_memory.c

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/*
 * Created: Thu Feb  4 14:00:34 1999 by [email protected]
 *
 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#include <linux/highmem.h>
#include <linux/export.h>
#include <drm/drmP.h>

#if __OS_HAS_AGP
static void *agp_remap(unsigned long offset, unsigned long size,
               struct drm_device * dev)
{
    unsigned long i, num_pages =
        PAGE_ALIGN(size) / PAGE_SIZE;
    struct drm_agp_mem *agpmem;
    struct page **page_map;
    struct page **phys_page_map;
    void *addr;

    size = PAGE_ALIGN(size);

#ifdef __alpha__
    offset -= dev->hose->mem_space->start;
#endif

    list_for_each_entry(agpmem, &dev->agp->memory, head)
        if (agpmem->bound <= offset
            && (agpmem->bound + (agpmem->pages << PAGE_SHIFT)) >=
            (offset + size))
            break;
    if (&agpmem->head == &dev->agp->memory)
        return NULL;

    /*
     * OK, we're mapping AGP space on a chipset/platform on which memory accesses by
     * the CPU do not get remapped by the GART.  We fix this by using the kernel's
     * page-table instead (that's probably faster anyhow...).
     */
    /* note: use vmalloc() because num_pages could be large... */
    page_map = vmalloc(num_pages * sizeof(struct page *));
    if (!page_map)
        return NULL;

    phys_page_map = (agpmem->memory->pages + (offset - agpmem->bound) / PAGE_SIZE);
    for (i = 0; i < num_pages; ++i)
        page_map[i] = phys_page_map[i];
    addr = vmap(page_map, num_pages, VM_IOREMAP, PAGE_AGP);
    vfree(page_map);

    return addr;
}

void drm_free_agp(DRM_AGP_MEM * handle, int pages)
{
    agp_free_memory(handle);
}
EXPORT_SYMBOL(drm_free_agp);

int drm_bind_agp(DRM_AGP_MEM * handle, unsigned int start)
{
    return agp_bind_memory(handle, start);
}

int drm_unbind_agp(DRM_AGP_MEM * handle)
{
    return agp_unbind_memory(handle);
}
EXPORT_SYMBOL(drm_unbind_agp);

#else  /*  __OS_HAS_AGP  */
static inline void *agp_remap(unsigned long offset, unsigned long size,
                  struct drm_device * dev)
{
    return NULL;
}

#endif              /* agp */

void drm_core_ioremap(struct drm_local_map *map, struct drm_device *dev)
{
    if (drm_core_has_AGP(dev) &&
        dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
        map->handle = agp_remap(map->offset, map->size, dev);
    else
        map->handle = ioremap(map->offset, map->size);
}
EXPORT_SYMBOL(drm_core_ioremap);

void drm_core_ioremap_wc(struct drm_local_map *map, struct drm_device *dev)
{
    if (drm_core_has_AGP(dev) &&
        dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
        map->handle = agp_remap(map->offset, map->size, dev);
    else
        map->handle = ioremap_wc(map->offset, map->size);
}
EXPORT_SYMBOL(drm_core_ioremap_wc);

void drm_core_ioremapfree(struct drm_local_map *map, struct drm_device *dev)
{
    if (!map->handle || !map->size)
        return;

    if (drm_core_has_AGP(dev) &&
        dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
        vunmap(map->handle);
    else
        iounmap(map->handle);
}
EXPORT_SYMBOL(drm_core_ioremapfree);