LXR linux/drivers/gpu/drm/drm

   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)
  35static void
  36drm_clflush_page(struct page *page)
  37{
  38        uint8_t *page_virtual;
  39        unsigned int i;
  40        const int size = boot_cpu_data.x86_clflush_size;
  41
  42        if (unlikely(page == NULL))
  43                return;
  44
  45        page_virtual = kmap_atomic(page);
  46        for (i = 0; i < PAGE_SIZE; i += size)
  47                clflush(page_virtual + i);
  48        kunmap_atomic(page_virtual);
  49}
  50
  51static void drm_cache_flush_clflush(struct page *pages[],
  52                                    unsigned long num_pages)
  53{
  54        unsigned long i;
  55
  56        mb();
  57        for (i = 0; i < num_pages; i++)
  58                drm_clflush_page(*pages++);
  59        mb();
  60}
  61
  62static void
  63drm_clflush_ipi_handler(void *null)
  64{
  65        wbinvd();
  66}
  67#endif
  68
  69void
  70drm_clflush_pages(struct page *pages[], unsigned long num_pages)
  71{
  72
  73#if defined(CONFIG_X86)
  74        if (cpu_has_clflush) {
  75                drm_cache_flush_clflush(pages, num_pages);
  76                return;
  77        }
  78
  79        if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0)
  80                printk(KERN_ERR "Timed out waiting for cache flush.\n");
  81
  82#elif defined(__powerpc__)
  83        unsigned long i;
  84        for (i = 0; i < num_pages; i++) {
  85                struct page *page = pages[i];
  86                void *page_virtual;
  87
  88                if (unlikely(page == NULL))
  89                        continue;
  90
  91                page_virtual = kmap_atomic(page);
  92                flush_dcache_range((unsigned long)page_virtual,
  93                                   (unsigned long)page_virtual + PAGE_SIZE);
  94                kunmap_atomic(page_virtual);
  95        }
  96#else
  97        printk(KERN_ERR "Architecture has no drm_cache.c support\n");
  98        WARN_ON_ONCE(1);
  99#endif
 100}
 101EXPORT_SYMBOL(drm_clflush_pages);
 102
 103void
 104drm_clflush_sg(struct sg_table *st)
 105{
 106#if defined(CONFIG_X86)
 107        if (cpu_has_clflush) {
 108                struct sg_page_iter sg_iter;
 109
 110                mb();
 111                for_each_sg_page(st->sgl, &sg_iter, st->nents, 0)
 112                        drm_clflush_page(sg_page_iter_page(&sg_iter));
 113                mb();
 114
 115                return;
 116        }
 117
 118        if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0)
 119                printk(KERN_ERR "Timed out waiting for cache flush.\n");
 120#else
 121        printk(KERN_ERR "Architecture has no drm_cache.c support\n");
 122        WARN_ON_ONCE(1);
 123#endif
 124}
 125EXPORT_SYMBOL(drm_clflush_sg);
 126
 127void
 128drm_clflush_virt_range(char *addr, unsigned long length)
 129{
 130#if defined(CONFIG_X86)
 131        if (cpu_has_clflush) {
 132                char *end = addr + length;
 133                mb();
 134                for (; addr < end; addr += boot_cpu_data.x86_clflush_size)
 135                        clflush(addr);
 136                clflush(end - 1);
 137                mb();
 138                return;
 139        }
 140
 141        if (on_each_cpu(drm_clflush_ipi_handler, NULL, 1) != 0)
 142                printk(KERN_ERR "Timed out waiting for cache flush.\n");
 143#else
 144        printk(KERN_ERR "Architecture has no drm_cache.c support\n");
 145        WARN_ON_ONCE(1);
 146#endif
 147}
 148EXPORT_SYMBOL(drm_clflush_virt_range);
 149