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 "drmP.h"
  33
  34 #if defined(CONFIG_X86)
  35 static void
  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, KM_USER0);
  45         for (i = 0; i < PAGE_SIZE; i += boot_cpu_data.x86_clflush_size)
  46                 clflush(page_virtual + i);
  47         kunmap_atomic(page_virtual, KM_USER0);
  48 }
  49
  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
  62 drm_clflush_ipi_handler(void *null)
  63 {
  64         wbinvd();
  65 }
  66 #endif
  67
  68 void
  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, KM_USER0);
  91                 flush_dcache_range((unsigned long)page_virtual,
  92                                    (unsigned long)page_virtual + PAGE_SIZE);
  93                 kunmap_atomic(page_virtual, KM_USER0);
  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);