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 "drmP.h"
33
34 #if defined(CONFIG_X86)
35 static void
drm_clflush_page(struct page * page)36 drm_clflush_page(struct page *page)
37 {
38 uint8_t *page_virtual;
39 unsigned int i;
40
41 if (unlikely(page == NULL))
42 return;
43
44 page_virtual = kmap_atomic(page);
45 for (i = 0; i < PAGE_SIZE; i += boot_cpu_data.x86_clflush_size)
46 clflush(page_virtual + i);
47 kunmap_atomic(page_virtual);
48 }
49
drm_cache_flush_clflush(struct page * pages[],unsigned long num_pages)50 static void drm_cache_flush_clflush(struct page *pages[],
51 unsigned long num_pages)
52 {
53 unsigned long i;
54
55 mb();
56 for (i = 0; i < num_pages; i++)
57 drm_clflush_page(*pages++);
58 mb();
59 }
60
61 static void
drm_clflush_ipi_handler(void * null)62 drm_clflush_ipi_handler(void *null)
63 {
64 wbinvd();
65 }
66 #endif
67
68 void
drm_clflush_pages(struct page * pages[],unsigned long num_pages)69 drm_clflush_pages(struct page *pages[], unsigned long num_pages)
70 {
71
72 #if defined(CONFIG_X86)
73 if (cpu_has_clflush) {
74 drm_cache_flush_clflush(pages, num_pages);
75 return;
76 }
77
78 if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0)
79 printk(KERN_ERR "Timed out waiting for cache flush.\n");
80
81 #elif defined(__powerpc__)
82 unsigned long i;
83 for (i = 0; i < num_pages; i++) {
84 struct page *page = pages[i];
85 void *page_virtual;
86
87 if (unlikely(page == NULL))
88 continue;
89
90 page_virtual = kmap_atomic(page);
91 flush_dcache_range((unsigned long)page_virtual,
92 (unsigned long)page_virtual + PAGE_SIZE);
93 kunmap_atomic(page_virtual);
94 }
95 #else
96 printk(KERN_ERR "Architecture has no drm_cache.c support\n");
97 WARN_ON_ONCE(1);
98 #endif
99 }
100 EXPORT_SYMBOL(drm_clflush_pages);
101