1 /**************************************************************************
2 *
3 * Copyright (c) 2006-2007 Tungsten Graphics, Inc., Cedar Park, TX., USA
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27 /*
28 * Authors: Thomas Hellström <thomas-at-tungstengraphics-dot-com>
29 */
30
31 #include <linux/export.h>
32 #include <linux/highmem.h>
33
34 #include <drm/drm_cache.h>
35
36 #if defined(CONFIG_X86)
37 #include <asm/smp.h>
38
39 /*
40 * clflushopt is an unordered instruction which needs fencing with mfence or
41 * sfence to avoid ordering issues. For drm_clflush_page this fencing happens
42 * in the caller.
43 */
44 static void
drm_clflush_page(struct page * page)45 drm_clflush_page(struct page *page)
46 {
47 uint8_t *page_virtual;
48 unsigned int i;
49 const int size = boot_cpu_data.x86_clflush_size;
50
51 if (unlikely(page == NULL))
52 return;
53
54 page_virtual = kmap_atomic(page);
55 for (i = 0; i < PAGE_SIZE; i += size)
56 clflushopt(page_virtual + i);
57 kunmap_atomic(page_virtual);
58 }
59
drm_cache_flush_clflush(struct page * pages[],unsigned long num_pages)60 static void drm_cache_flush_clflush(struct page *pages[],
61 unsigned long num_pages)
62 {
63 unsigned long i;
64
65 mb();
66 for (i = 0; i < num_pages; i++)
67 drm_clflush_page(*pages++);
68 mb();
69 }
70 #endif
71
72 void
drm_clflush_pages(struct page * pages[],unsigned long num_pages)73 drm_clflush_pages(struct page *pages[], unsigned long num_pages)
74 {
75
76 #if defined(CONFIG_X86)
77 if (static_cpu_has(X86_FEATURE_CLFLUSH)) {
78 drm_cache_flush_clflush(pages, num_pages);
79 return;
80 }
81
82 cpu_wbinvd_on_all_cpus();
83
84 #elif defined(__powerpc__)
85 unsigned long i;
86 for (i = 0; i < num_pages; i++) {
87 struct page *page = pages[i];
88 void *page_virtual;
89
90 if (unlikely(page == NULL))
91 continue;
92
93 page_virtual = kmap_atomic(page);
94 flush_dcache_range((unsigned long)page_virtual,
95 (unsigned long)page_virtual + PAGE_SIZE);
96 kunmap_atomic(page_virtual);
97 }
98 #else
99 pr_err("Architecture has no drm_cache.c support\n");
100 WARN_ON_ONCE(1);
101 #endif
102 }
103 EXPORT_SYMBOL(drm_clflush_pages);
104
105 void
drm_clflush_sg(struct sg_table * st)106 drm_clflush_sg(struct sg_table *st)
107 {
108 #if defined(CONFIG_X86)
109 if (static_cpu_has(X86_FEATURE_CLFLUSH)) {
110 struct sg_page_iter sg_iter;
111
112 mb();
113 for_each_sg_page(st->sgl, &sg_iter, st->nents, 0)
114 drm_clflush_page(sg_page_iter_page(&sg_iter));
115 mb();
116
117 return;
118 }
119
120 cpu_wbinvd_on_all_cpus();
121 #else
122 printk(KERN_ERR "Architecture has no drm_cache.c support\n");
123 WARN_ON_ONCE(1);
124 #endif
125 }
126 EXPORT_SYMBOL(drm_clflush_sg);
127
128 void
drm_clflush_virt_range(void * addr,unsigned long length)129 drm_clflush_virt_range(void *addr, unsigned long length)
130 {
131 #if defined(CONFIG_X86)
132 if (static_cpu_has(X86_FEATURE_CLFLUSH)) {
133 const int size = boot_cpu_data.x86_clflush_size;
134 void *end = addr + length;
135 addr = (void *)(((unsigned long)addr) & -size);
136 mb();
137 for (; addr < end; addr += size)
138 clflushopt(addr);
139 clflushopt(end - 1); /* force serialisation */
140 mb();
141 return;
142 }
143
144 cpu_wbinvd_on_all_cpus();
145 #else
146 printk(KERN_ERR "Architecture has no drm_cache.c support\n");
147 WARN_ON_ONCE(1);
148 #endif
149 }
150 EXPORT_SYMBOL(drm_clflush_virt_range);
151