1 /**************************************************************************
3 * Copyright (c) 2006-2007 Tungsten Graphics, Inc., Cedar Park, TX., USA
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:
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
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.
26 **************************************************************************/
28 * Authors: Thomas Hellström <thomas-at-tungstengraphics-dot-com>
31 #include <linux/export.h>
34 #if defined(CONFIG_X86)
37 * clflushopt is an unordered instruction which needs fencing with mfence or
38 * sfence to avoid ordering issues. For drm_clflush_page this fencing happens
42 drm_clflush_page(struct page *page)
44 uint8_t *page_virtual;
46 const int size = boot_cpu_data.x86_clflush_size;
48 if (unlikely(page == NULL))
51 page_virtual = kmap_atomic(page);
52 for (i = 0; i < PAGE_SIZE; i += size)
53 clflushopt(page_virtual + i);
54 kunmap_atomic(page_virtual);
57 static void drm_cache_flush_clflush(struct page *pages[],
58 unsigned long num_pages)
63 for (i = 0; i < num_pages; i++)
64 drm_clflush_page(*pages++);
69 drm_clflush_ipi_handler(void *null)
76 drm_clflush_pages(struct page *pages[], unsigned long num_pages)
79 #if defined(CONFIG_X86)
80 if (cpu_has_clflush) {
81 drm_cache_flush_clflush(pages, num_pages);
85 if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0)
86 printk(KERN_ERR "Timed out waiting for cache flush.\n");
88 #elif defined(__powerpc__)
90 for (i = 0; i < num_pages; i++) {
91 struct page *page = pages[i];
94 if (unlikely(page == NULL))
97 page_virtual = kmap_atomic(page);
98 flush_dcache_range((unsigned long)page_virtual,
99 (unsigned long)page_virtual + PAGE_SIZE);
100 kunmap_atomic(page_virtual);
103 printk(KERN_ERR "Architecture has no drm_cache.c support\n");
107 EXPORT_SYMBOL(drm_clflush_pages);
110 drm_clflush_sg(struct sg_table *st)
112 #if defined(CONFIG_X86)
113 if (cpu_has_clflush) {
114 struct sg_page_iter sg_iter;
117 for_each_sg_page(st->sgl, &sg_iter, st->nents, 0)
118 drm_clflush_page(sg_page_iter_page(&sg_iter));
124 if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0)
125 printk(KERN_ERR "Timed out waiting for cache flush.\n");
127 printk(KERN_ERR "Architecture has no drm_cache.c support\n");
131 EXPORT_SYMBOL(drm_clflush_sg);
134 drm_clflush_virt_range(char *addr, unsigned long length)
136 #if defined(CONFIG_X86)
137 if (cpu_has_clflush) {
138 char *end = addr + length;
140 for (; addr < end; addr += boot_cpu_data.x86_clflush_size)
147 if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0)
148 printk(KERN_ERR "Timed out waiting for cache flush.\n");
150 printk(KERN_ERR "Architecture has no drm_cache.c support\n");
154 EXPORT_SYMBOL(drm_clflush_virt_range);