drivers/gpu/drm/drm_cache.c

   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 <drm/drmP.h>
  33
  34 #if defined(CONFIG_X86)
  35 #include <asm/smp.h>
  36
  37 /*
  38  * clflushopt is an unordered instruction which needs fencing with mfence or
  39  * sfence to avoid ordering issues.  For drm_clflush_page this fencing happens
  40  * in the caller.
  41  */
  42 static void
  43 drm_clflush_page(struct page *page)
  44 {
  45         uint8_t *page_virtual;
  46         unsigned int i;
  47         const int size = boot_cpu_data.x86_clflush_size;
  48
  49         if (unlikely(page == NULL))
  50                 return;
  51
  52         page_virtual = kmap_atomic(page);
  53         for (i = 0; i < PAGE_SIZE; i += size)
  54                 clflushopt(page_virtual + i);
  55         kunmap_atomic(page_virtual);
  56 }
  57
  58 static void drm_cache_flush_clflush(struct page *pages[],
  59                                     unsigned long num_pages)
  60 {
  61         unsigned long i;
  62
  63         mb();
  64         for (i = 0; i < num_pages; i++)
  65                 drm_clflush_page(*pages++);
  66         mb();
  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 (wbinvd_on_all_cpus())
  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 (wbinvd_on_all_cpus())
 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(void *addr, unsigned long length)
 130 {
 131 #if defined(CONFIG_X86)
 132         if (cpu_has_clflush) {
 133                 const int size = boot_cpu_data.x86_clflush_size;
 134                 void *end = addr + length;
 135                 addr = (void *)(((unsigned long)addr) & -size);
 136                 mb();
 137                 for (; addr < end; addr += size)
 138                         clflushopt(addr);
 139                 mb();
 140                 return;
 141         }
 142
 143         if (wbinvd_on_all_cpus())
 144                 printk(KERN_ERR "Timed out waiting for cache flush.\n");
 145 #else
 146         printk(KERN_ERR "Architecture has no drm_cache.c support\n");
 147         WARN_ON_ONCE(1);
 148 #endif
 149 }
 150 EXPORT_SYMBOL(drm_clflush_virt_range);