xref: /openbmc/linux/drivers/gpu/drm/drm_memory.c (revision feac8c8b)
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_noncached_wc(PAGE_KERNEL)
48 # else
49 #  define PAGE_AGP	PAGE_KERNEL
50 # endif
51 #endif
52 
53 static 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() */
97 void drm_free_agp(struct agp_memory * handle, int pages)
98 {
99 	agp_free_memory(handle);
100 }
101 
102 /** Wrapper around agp_bind_memory() */
103 int 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() */
109 int drm_unbind_agp(struct agp_memory * handle)
110 {
111 	return agp_unbind_memory(handle);
112 }
113 
114 #else /*  CONFIG_AGP  */
115 static 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 
123 void 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 }
130 EXPORT_SYMBOL(drm_legacy_ioremap);
131 
132 void 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 }
139 EXPORT_SYMBOL(drm_legacy_ioremap_wc);
140 
141 void 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 }
151 EXPORT_SYMBOL(drm_legacy_ioremapfree);
152