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#if __OS_HAS_AGP
 41static 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() */
 85void drm_free_agp(DRM_AGP_MEM * handle, int pages)
 86{
 87	agp_free_memory(handle);
 88}
 89EXPORT_SYMBOL(drm_free_agp);
 90
 91/** Wrapper around agp_bind_memory() */
 92int drm_bind_agp(DRM_AGP_MEM * handle, unsigned int start)
 93{
 94	return agp_bind_memory(handle, start);
 95}
 96
 97/** Wrapper around agp_unbind_memory() */
 98int drm_unbind_agp(DRM_AGP_MEM * handle)
 99{
100	return agp_unbind_memory(handle);
101}
102EXPORT_SYMBOL(drm_unbind_agp);
103
104#else  /*  __OS_HAS_AGP  */
105static inline void *agp_remap(unsigned long offset, unsigned long size,
106			      struct drm_device * dev)
107{
108	return NULL;
109}
110
111#endif				/* agp */
112
113void drm_core_ioremap(struct drm_local_map *map, struct drm_device *dev)
114{
115	if (drm_core_has_AGP(dev) &&
116	    dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
117		map->handle = agp_remap(map->offset, map->size, dev);
118	else
119		map->handle = ioremap(map->offset, map->size);
120}
121EXPORT_SYMBOL(drm_core_ioremap);
122
123void drm_core_ioremap_wc(struct drm_local_map *map, struct drm_device *dev)
124{
125	if (drm_core_has_AGP(dev) &&
126	    dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
127		map->handle = agp_remap(map->offset, map->size, dev);
128	else
129		map->handle = ioremap_wc(map->offset, map->size);
130}
131EXPORT_SYMBOL(drm_core_ioremap_wc);
132
133void drm_core_ioremapfree(struct drm_local_map *map, struct drm_device *dev)
134{
135	if (!map->handle || !map->size)
136		return;
137
138	if (drm_core_has_AGP(dev) &&
139	    dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
140		vunmap(map->handle);
141	else
142		iounmap(map->handle);
143}
144EXPORT_SYMBOL(drm_core_ioremapfree);