linux/drivers/char/drm/drm_memory.h
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

197 lines
5.5 KiB
C

/**
* \file drm_memory.h
* Memory management wrappers for DRM
*
* \author Rickard E. (Rik) Faith <faith@valinux.com>
* \author Gareth Hughes <gareth@valinux.com>
*/
/*
* Created: Thu Feb 4 14:00:34 1999 by faith@valinux.com
*
* 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/config.h>
#include <linux/highmem.h>
#include <linux/vmalloc.h>
#include "drmP.h"
/**
* Cut down version of drm_memory_debug.h, which used to be called
* drm_memory.h.
*/
#if __OS_HAS_AGP
#include <linux/vmalloc.h>
#ifdef HAVE_PAGE_AGP
#include <asm/agp.h>
#else
# ifdef __powerpc__
# define PAGE_AGP __pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
# else
# define PAGE_AGP PAGE_KERNEL
# endif
#endif
/*
* Find the drm_map that covers the range [offset, offset+size).
*/
static inline drm_map_t *
drm_lookup_map (unsigned long offset, unsigned long size, drm_device_t *dev)
{
struct list_head *list;
drm_map_list_t *r_list;
drm_map_t *map;
list_for_each(list, &dev->maplist->head) {
r_list = (drm_map_list_t *) list;
map = r_list->map;
if (!map)
continue;
if (map->offset <= offset && (offset + size) <= (map->offset + map->size))
return map;
}
return NULL;
}
static inline void *
agp_remap (unsigned long offset, unsigned long size, drm_device_t *dev)
{
unsigned long *phys_addr_map, i, num_pages = PAGE_ALIGN(size) / PAGE_SIZE;
struct drm_agp_mem *agpmem;
struct page **page_map;
void *addr;
size = PAGE_ALIGN(size);
#ifdef __alpha__
offset -= dev->hose->mem_space->start;
#endif
for (agpmem = dev->agp->memory; agpmem; agpmem = agpmem->next)
if (agpmem->bound <= offset
&& (agpmem->bound + (agpmem->pages << PAGE_SHIFT)) >= (offset + size))
break;
if (!agpmem)
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_addr_map = agpmem->memory->memory + (offset - agpmem->bound) / PAGE_SIZE;
for (i = 0; i < num_pages; ++i)
page_map[i] = pfn_to_page(phys_addr_map[i] >> PAGE_SHIFT);
addr = vmap(page_map, num_pages, VM_IOREMAP, PAGE_AGP);
vfree(page_map);
return addr;
}
static inline unsigned long
drm_follow_page (void *vaddr)
{
pgd_t *pgd = pgd_offset_k((unsigned long) vaddr);
pud_t *pud = pud_offset(pgd, (unsigned long) vaddr);
pmd_t *pmd = pmd_offset(pud, (unsigned long) vaddr);
pte_t *ptep = pte_offset_kernel(pmd, (unsigned long) vaddr);
return pte_pfn(*ptep) << PAGE_SHIFT;
}
#else /* __OS_HAS_AGP */
static inline drm_map_t *drm_lookup_map(unsigned long offset, unsigned long size, drm_device_t *dev)
{
return NULL;
}
static inline void *agp_remap(unsigned long offset, unsigned long size, drm_device_t *dev)
{
return NULL;
}
static inline unsigned long drm_follow_page (void *vaddr)
{
return 0;
}
#endif
static inline void *drm_ioremap(unsigned long offset, unsigned long size, drm_device_t *dev)
{
if (drm_core_has_AGP(dev) && dev->agp && dev->agp->cant_use_aperture) {
drm_map_t *map = drm_lookup_map(offset, size, dev);
if (map && map->type == _DRM_AGP)
return agp_remap(offset, size, dev);
}
return ioremap(offset, size);
}
static inline void *drm_ioremap_nocache(unsigned long offset, unsigned long size,
drm_device_t *dev)
{
if (drm_core_has_AGP(dev) && dev->agp && dev->agp->cant_use_aperture) {
drm_map_t *map = drm_lookup_map(offset, size, dev);
if (map && map->type == _DRM_AGP)
return agp_remap(offset, size, dev);
}
return ioremap_nocache(offset, size);
}
static inline void drm_ioremapfree(void *pt, unsigned long size, drm_device_t *dev)
{
/*
* This is a bit ugly. It would be much cleaner if the DRM API would use separate
* routines for handling mappings in the AGP space. Hopefully this can be done in
* a future revision of the interface...
*/
if (drm_core_has_AGP(dev) && dev->agp && dev->agp->cant_use_aperture
&& ((unsigned long) pt >= VMALLOC_START && (unsigned long) pt < VMALLOC_END))
{
unsigned long offset;
drm_map_t *map;
offset = drm_follow_page(pt) | ((unsigned long) pt & ~PAGE_MASK);
map = drm_lookup_map(offset, size, dev);
if (map && map->type == _DRM_AGP) {
vunmap(pt);
return;
}
}
iounmap(pt);
}