xref: /openbmc/linux/drivers/gpu/drm/drm_cache.c (revision 7dd65feb)
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 "drmP.h"
32 
33 #if defined(CONFIG_X86)
34 static void
35 drm_clflush_page(struct page *page)
36 {
37 	uint8_t *page_virtual;
38 	unsigned int i;
39 
40 	if (unlikely(page == NULL))
41 		return;
42 
43 	page_virtual = kmap_atomic(page, KM_USER0);
44 	for (i = 0; i < PAGE_SIZE; i += boot_cpu_data.x86_clflush_size)
45 		clflush(page_virtual + i);
46 	kunmap_atomic(page_virtual, KM_USER0);
47 }
48 
49 static void drm_cache_flush_clflush(struct page *pages[],
50 				    unsigned long num_pages)
51 {
52 	unsigned long i;
53 
54 	mb();
55 	for (i = 0; i < num_pages; i++)
56 		drm_clflush_page(*pages++);
57 	mb();
58 }
59 
60 static void
61 drm_clflush_ipi_handler(void *null)
62 {
63 	wbinvd();
64 }
65 #endif
66 
67 void
68 drm_clflush_pages(struct page *pages[], unsigned long num_pages)
69 {
70 
71 #if defined(CONFIG_X86)
72 	if (cpu_has_clflush) {
73 		drm_cache_flush_clflush(pages, num_pages);
74 		return;
75 	}
76 
77 	if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0)
78 		printk(KERN_ERR "Timed out waiting for cache flush.\n");
79 
80 #elif defined(__powerpc__)
81 	unsigned long i;
82 	for (i = 0; i < num_pages; i++) {
83 		struct page *page = pages[i];
84 		void *page_virtual;
85 
86 		if (unlikely(page == NULL))
87 			continue;
88 
89 		page_virtual = kmap_atomic(page, KM_USER0);
90 		flush_dcache_range((unsigned long)page_virtual,
91 				   (unsigned long)page_virtual + PAGE_SIZE);
92 		kunmap_atomic(page_virtual, KM_USER0);
93 	}
94 #else
95 	printk(KERN_ERR "Architecture has no drm_cache.c support\n");
96 	WARN_ON_ONCE(1);
97 #endif
98 }
99 EXPORT_SYMBOL(drm_clflush_pages);
100