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 <drm/drmP.h>
 39#include "drm_legacy.h"
 40
 41#if IS_ENABLED(CONFIG_AGP)
 42
 43#ifdef HAVE_PAGE_AGP
 44# include <asm/agp.h>
 45#else
 46# ifdef __powerpc__
 47#  define PAGE_AGP	__pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
 48# else
 49#  define PAGE_AGP	PAGE_KERNEL
 50# endif
 51#endif
 52
 53static void *agp_remap(unsigned long offset, unsigned long size,
 54		       struct drm_device * dev)
 55{
 56	unsigned long i, num_pages =
 57	    PAGE_ALIGN(size) / PAGE_SIZE;
 58	struct drm_agp_mem *agpmem;
 59	struct page **page_map;
 60	struct page **phys_page_map;
 61	void *addr;
 62
 63	size = PAGE_ALIGN(size);
 64
 65#ifdef __alpha__
 66	offset -= dev->hose->mem_space->start;
 67#endif
 68
 69	list_for_each_entry(agpmem, &dev->agp->memory, head)
 70		if (agpmem->bound <= offset
 71		    && (agpmem->bound + (agpmem->pages << PAGE_SHIFT)) >=
 72		    (offset + size))
 73			break;
 74	if (&agpmem->head == &dev->agp->memory)
 75		return NULL;
 76
 77	/*
 78	 * OK, we're mapping AGP space on a chipset/platform on which memory accesses by
 79	 * the CPU do not get remapped by the GART.  We fix this by using the kernel's
 80	 * page-table instead (that's probably faster anyhow...).
 81	 */
 82	/* note: use vmalloc() because num_pages could be large... */
 83	page_map = vmalloc(num_pages * sizeof(struct page *));
 84	if (!page_map)
 85		return NULL;
 86
 87	phys_page_map = (agpmem->memory->pages + (offset - agpmem->bound) / PAGE_SIZE);
 88	for (i = 0; i < num_pages; ++i)
 89		page_map[i] = phys_page_map[i];
 90	addr = vmap(page_map, num_pages, VM_IOREMAP, PAGE_AGP);
 91	vfree(page_map);
 92
 93	return addr;
 94}
 95
 96/** Wrapper around agp_free_memory() */
 97void drm_free_agp(struct agp_memory * handle, int pages)
 98{
 99	agp_free_memory(handle);
100}
101
102/** Wrapper around agp_bind_memory() */
103int drm_bind_agp(struct agp_memory * handle, unsigned int start)
104{
105	return agp_bind_memory(handle, start);
106}
107
108/** Wrapper around agp_unbind_memory() */
109int drm_unbind_agp(struct agp_memory * handle)
110{
111	return agp_unbind_memory(handle);
112}
113
114#else /*  CONFIG_AGP  */
115static inline void *agp_remap(unsigned long offset, unsigned long size,
116			      struct drm_device * dev)
117{
118	return NULL;
119}
120
121#endif /* CONFIG_AGP */
122
123void drm_legacy_ioremap(struct drm_local_map *map, struct drm_device *dev)
124{
125	if (dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
126		map->handle = agp_remap(map->offset, map->size, dev);
127	else
128		map->handle = ioremap(map->offset, map->size);
129}
130EXPORT_SYMBOL(drm_legacy_ioremap);
131
132void drm_legacy_ioremap_wc(struct drm_local_map *map, struct drm_device *dev)
133{
134	if (dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
135		map->handle = agp_remap(map->offset, map->size, dev);
136	else
137		map->handle = ioremap_wc(map->offset, map->size);
138}
139EXPORT_SYMBOL(drm_legacy_ioremap_wc);
140
141void drm_legacy_ioremapfree(struct drm_local_map *map, struct drm_device *dev)
142{
143	if (!map->handle || !map->size)
144		return;
145
146	if (dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
147		vunmap(map->handle);
148	else
149		iounmap(map->handle);
150}
151EXPORT_SYMBOL(drm_legacy_ioremapfree);