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);
152