xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/drm_memory.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /*	$NetBSD: drm_memory.c,v 1.2 2018/08/27 04:58:19 riastradh Exp $	*/
2 
3 /**
4  * \file drm_memory.c
5  * Memory management wrappers for DRM
6  *
7  * \author Rickard E. (Rik) Faith <faith@valinux.com>
8  * \author Gareth Hughes <gareth@valinux.com>
9  */
10 
11 /*
12  * Created: Thu Feb  4 14:00:34 1999 by faith@valinux.com
13  *
14  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
15  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
16  * All Rights Reserved.
17  *
18  * Permission is hereby granted, free of charge, to any person obtaining a
19  * copy of this software and associated documentation files (the "Software"),
20  * to deal in the Software without restriction, including without limitation
21  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
22  * and/or sell copies of the Software, and to permit persons to whom the
23  * Software is furnished to do so, subject to the following conditions:
24  *
25  * The above copyright notice and this permission notice (including the next
26  * paragraph) shall be included in all copies or substantial portions of the
27  * Software.
28  *
29  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
30  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
31  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
32  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
33  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
34  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
35  * OTHER DEALINGS IN THE SOFTWARE.
36  */
37 
38 #include <sys/cdefs.h>
39 __KERNEL_RCSID(0, "$NetBSD: drm_memory.c,v 1.2 2018/08/27 04:58:19 riastradh Exp $");
40 
41 #include <linux/highmem.h>
42 #include <linux/export.h>
43 #include <drm/drmP.h>
44 #include "drm_legacy.h"
45 
46 #if IS_ENABLED(CONFIG_AGP)
47 
48 #ifdef HAVE_PAGE_AGP
49 # include <asm/agp.h>
50 #else
51 # ifdef __powerpc__
52 #  define PAGE_AGP	__pgprot(_PAGE_KERNEL | _PAGE_NO_CACHE)
53 # else
54 #  define PAGE_AGP	PAGE_KERNEL
55 # endif
56 #endif
57 
58 static void *agp_remap(unsigned long offset, unsigned long size,
59 		       struct drm_device * dev)
60 {
61 	unsigned long i, num_pages =
62 	    PAGE_ALIGN(size) / PAGE_SIZE;
63 	struct drm_agp_mem *agpmem;
64 	struct page **page_map;
65 	struct page **phys_page_map;
66 	void *addr;
67 
68 	size = PAGE_ALIGN(size);
69 
70 #ifdef __alpha__
71 	offset -= dev->hose->mem_space->start;
72 #endif
73 
74 	list_for_each_entry(agpmem, &dev->agp->memory, head)
75 		if (agpmem->bound <= offset
76 		    && (agpmem->bound + (agpmem->pages << PAGE_SHIFT)) >=
77 		    (offset + size))
78 			break;
79 	if (&agpmem->head == &dev->agp->memory)
80 		return NULL;
81 
82 	/*
83 	 * OK, we're mapping AGP space on a chipset/platform on which memory accesses by
84 	 * the CPU do not get remapped by the GART.  We fix this by using the kernel's
85 	 * page-table instead (that's probably faster anyhow...).
86 	 */
87 	/* note: use vmalloc() because num_pages could be large... */
88 	page_map = vmalloc(num_pages * sizeof(struct page *));
89 	if (!page_map)
90 		return NULL;
91 
92 	phys_page_map = (agpmem->memory->pages + (offset - agpmem->bound) / PAGE_SIZE);
93 	for (i = 0; i < num_pages; ++i)
94 		page_map[i] = phys_page_map[i];
95 	addr = vmap(page_map, num_pages, VM_IOREMAP, PAGE_AGP);
96 	vfree(page_map);
97 
98 	return addr;
99 }
100 
101 /** Wrapper around agp_free_memory() */
102 void drm_free_agp(struct agp_memory * handle, int pages)
103 {
104 	agp_free_memory(handle);
105 }
106 
107 /** Wrapper around agp_bind_memory() */
108 int drm_bind_agp(struct agp_memory * handle, unsigned int start)
109 {
110 	return agp_bind_memory(handle, start);
111 }
112 
113 /** Wrapper around agp_unbind_memory() */
114 int drm_unbind_agp(struct agp_memory * handle)
115 {
116 	return agp_unbind_memory(handle);
117 }
118 
119 #else /*  CONFIG_AGP  */
120 static inline void *agp_remap(unsigned long offset, unsigned long size,
121 			      struct drm_device * dev)
122 {
123 	return NULL;
124 }
125 
126 #endif /* CONFIG_AGP */
127 
128 void drm_legacy_ioremap(struct drm_local_map *map, struct drm_device *dev)
129 {
130 	if (dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
131 		map->handle = agp_remap(map->offset, map->size, dev);
132 	else
133 		map->handle = ioremap(map->offset, map->size);
134 }
135 EXPORT_SYMBOL(drm_legacy_ioremap);
136 
137 void drm_legacy_ioremap_wc(struct drm_local_map *map, struct drm_device *dev)
138 {
139 	if (dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
140 		map->handle = agp_remap(map->offset, map->size, dev);
141 	else
142 		map->handle = ioremap_wc(map->offset, map->size);
143 }
144 EXPORT_SYMBOL(drm_legacy_ioremap_wc);
145 
146 void drm_legacy_ioremapfree(struct drm_local_map *map, struct drm_device *dev)
147 {
148 	if (!map->handle || !map->size)
149 		return;
150 
151 	if (dev->agp && dev->agp->cant_use_aperture && map->type == _DRM_AGP)
152 		vunmap(map->handle);
153 	else
154 		iounmap(map->handle);
155 }
156 EXPORT_SYMBOL(drm_legacy_ioremapfree);
157