1 /* $OpenBSD: drm_cache.c,v 1.2 2015/09/23 23:12:11 kettenis Exp $ */ 2 /************************************************************************** 3 * 4 * Copyright (c) 2006-2007 Tungsten Graphics, Inc., Cedar Park, TX., USA 5 * All Rights Reserved. 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a 8 * copy of this software and associated documentation files (the 9 * "Software"), to deal in the Software without restriction, including 10 * without limitation the rights to use, copy, modify, merge, publish, 11 * distribute, sub license, and/or sell copies of the Software, and to 12 * permit persons to whom the Software is furnished to do so, subject to 13 * the following conditions: 14 * 15 * The above copyright notice and this permission notice (including the 16 * next paragraph) shall be included in all copies or substantial portions 17 * of the Software. 18 * 19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 21 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 22 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, 23 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 24 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 25 * USE OR OTHER DEALINGS IN THE SOFTWARE. 26 * 27 **************************************************************************/ 28 /* 29 * Authors: Thomas Hellström <thomas-at-tungstengraphics-dot-com> 30 */ 31 32 #include <linux/export.h> 33 #include <drm/drmP.h> 34 35 #if defined(CONFIG_X86) 36 static void 37 drm_clflush_page(struct page *page) 38 { 39 uint8_t *page_virtual; 40 unsigned int i; 41 const int size = boot_cpu_data.x86_clflush_size; 42 43 if (unlikely(page == NULL)) 44 return; 45 46 page_virtual = kmap_atomic(page); 47 for (i = 0; i < PAGE_SIZE; i += size) 48 clflush(page_virtual + i); 49 kunmap_atomic(page_virtual); 50 } 51 52 static void drm_cache_flush_clflush(struct page *pages[], 53 unsigned long num_pages) 54 { 55 unsigned long i; 56 57 mb(); 58 for (i = 0; i < num_pages; i++) 59 drm_clflush_page(*pages++); 60 mb(); 61 } 62 63 static void 64 drm_clflush_ipi_handler(void *null) 65 { 66 wbinvd(); 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 (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0) 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 (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0) 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(char *addr, unsigned long length) 130 { 131 #if defined(CONFIG_X86) 132 if (cpu_has_clflush) { 133 char *end = addr + length; 134 mb(); 135 for (; addr < end; addr += boot_cpu_data.x86_clflush_size) 136 clflush(addr); 137 clflush(end - 1); 138 mb(); 139 return; 140 } 141 142 if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0) 143 printk(KERN_ERR "Timed out waiting for cache flush.\n"); 144 #else 145 printk(KERN_ERR "Architecture has no drm_cache.c support\n"); 146 WARN_ON_ONCE(1); 147 #endif 148 } 149 EXPORT_SYMBOL(drm_clflush_virt_range); 150