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>
33 #include <asm/cpufeature.h>
36 * clflushopt is an unordered instruction which needs fencing with mfence or
37 * sfence to avoid ordering issues. For drm_clflush_page this fencing happens
41 drm_clflush_page(struct page *page)
43 uint8_t *page_virtual;
45 const int size = cpu_clflush_line_size;
47 if (unlikely(page == NULL))
50 page_virtual = kmap_atomic(page);
51 for (i = 0; i < PAGE_SIZE; i += size)
52 clflushopt(page_virtual + i);
53 kunmap_atomic(page_virtual);
56 static void drm_cache_flush_clflush(struct page *pages[],
57 unsigned long num_pages)
62 for (i = 0; i < num_pages; i++)
63 drm_clflush_page(*pages++);
68 drm_clflush_pages(struct page *pages[], unsigned long num_pages)
70 pmap_invalidate_cache_pages((struct vm_page **)pages, num_pages);
72 if (static_cpu_has(X86_FEATURE_CLFLUSH)) {
73 drm_cache_flush_clflush(pages, num_pages);
77 cpu_wbinvd_on_all_cpus();
79 EXPORT_SYMBOL(drm_clflush_pages);
82 drm_clflush_sg(struct sg_table *st)
84 if (static_cpu_has(X86_FEATURE_CLFLUSH)) {
85 struct sg_page_iter sg_iter;
88 for_each_sg_page(st->sgl, &sg_iter, st->nents, 0)
89 drm_clflush_page(sg_page_iter_page(&sg_iter));
95 cpu_wbinvd_on_all_cpus();
97 EXPORT_SYMBOL(drm_clflush_sg);
100 drm_clflush_virt_range(void *in_addr, unsigned long length)
102 char *addr = in_addr;
104 if (static_cpu_has(X86_FEATURE_CLFLUSH)) {
105 const int size = cpu_clflush_line_size;
106 char *end = addr + length;
107 addr = (void *)(((unsigned long)addr) & -size);
109 for (; addr < end; addr += size)
111 clflushopt(end - 1); /* force serialisation */
116 cpu_wbinvd_on_all_cpus();
118 EXPORT_SYMBOL(drm_clflush_virt_range);