xref: /openbmc/linux/drivers/gpu/drm/drm_cache.c (revision e2f1cf25)
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 <drm/drmP.h>
33 
34 #if defined(CONFIG_X86)
35 #include <asm/smp.h>
36 
37 /*
38  * clflushopt is an unordered instruction which needs fencing with mfence or
39  * sfence to avoid ordering issues.  For drm_clflush_page this fencing happens
40  * in the caller.
41  */
42 static void
43 drm_clflush_page(struct page *page)
44 {
45 	uint8_t *page_virtual;
46 	unsigned int i;
47 	const int size = boot_cpu_data.x86_clflush_size;
48 
49 	if (unlikely(page == NULL))
50 		return;
51 
52 	page_virtual = kmap_atomic(page);
53 	for (i = 0; i < PAGE_SIZE; i += size)
54 		clflushopt(page_virtual + i);
55 	kunmap_atomic(page_virtual);
56 }
57 
58 static void drm_cache_flush_clflush(struct page *pages[],
59 				    unsigned long num_pages)
60 {
61 	unsigned long i;
62 
63 	mb();
64 	for (i = 0; i < num_pages; i++)
65 		drm_clflush_page(*pages++);
66 	mb();
67 }
68 #endif
69 
70 void
71 drm_clflush_pages(struct page *pages[], unsigned long num_pages)
72 {
73 
74 #if defined(CONFIG_X86)
75 	if (cpu_has_clflush) {
76 		drm_cache_flush_clflush(pages, num_pages);
77 		return;
78 	}
79 
80 	if (wbinvd_on_all_cpus())
81 		printk(KERN_ERR "Timed out waiting for cache flush.\n");
82 
83 #elif defined(__powerpc__)
84 	unsigned long i;
85 	for (i = 0; i < num_pages; i++) {
86 		struct page *page = pages[i];
87 		void *page_virtual;
88 
89 		if (unlikely(page == NULL))
90 			continue;
91 
92 		page_virtual = kmap_atomic(page);
93 		flush_dcache_range((unsigned long)page_virtual,
94 				   (unsigned long)page_virtual + PAGE_SIZE);
95 		kunmap_atomic(page_virtual);
96 	}
97 #else
98 	printk(KERN_ERR "Architecture has no drm_cache.c support\n");
99 	WARN_ON_ONCE(1);
100 #endif
101 }
102 EXPORT_SYMBOL(drm_clflush_pages);
103 
104 void
105 drm_clflush_sg(struct sg_table *st)
106 {
107 #if defined(CONFIG_X86)
108 	if (cpu_has_clflush) {
109 		struct sg_page_iter sg_iter;
110 
111 		mb();
112 		for_each_sg_page(st->sgl, &sg_iter, st->nents, 0)
113 			drm_clflush_page(sg_page_iter_page(&sg_iter));
114 		mb();
115 
116 		return;
117 	}
118 
119 	if (wbinvd_on_all_cpus())
120 		printk(KERN_ERR "Timed out waiting for cache flush.\n");
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
129 drm_clflush_virt_range(void *addr, unsigned long length)
130 {
131 #if defined(CONFIG_X86)
132 	if (cpu_has_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 		mb();
140 		return;
141 	}
142 
143 	if (wbinvd_on_all_cpus())
144 		printk(KERN_ERR "Timed out waiting for cache flush.\n");
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