sys/dev/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 #include <asm/cpufeature.h>
  34
  35 #include <machine/md_var.h>
  36 #include <machine/cpufunc.h>
  37
  38 /*
  39  * clflushopt is an unordered instruction which needs fencing with mfence or
  40  * sfence to avoid ordering issues.  For drm_clflush_page this fencing happens
  41  * in the caller.
  42  */
  43 static void
  44 drm_clflush_page(struct vm_page *page)
  45 {
  46         uint8_t *page_virtual;
  47         unsigned int i;
  48         const int size = cpu_clflush_line_size;
  49
  50         if (unlikely(page == NULL))
  51                 return;
  52
  53         page_virtual = kmap_atomic(page);
  54         for (i = 0; i < PAGE_SIZE; i += size)
  55                 clflush((u_long)(page_virtual + i));
  56         kunmap_atomic(page_virtual);
  57 }
  58
  59 void
  60 drm_clflush_pages(vm_page_t *pages, unsigned long num_pages)
  61 {
  62         pmap_invalidate_cache_pages(pages, num_pages);
  63 }
  64
  65 void
  66 drm_clflush_sg(struct sg_table *st)
  67 {
  68         if (cpu_has_clflush) {
  69                 struct sg_page_iter sg_iter;
  70
  71                 mb();
  72                 for_each_sg_page(st->sgl, &sg_iter, st->nents, 0)
  73                         drm_clflush_page(sg_page_iter_page(&sg_iter));
  74                 mb();
  75
  76                 return;
  77         }
  78
  79         cpu_wbinvd_on_all_cpus();
  80 }
  81 EXPORT_SYMBOL(drm_clflush_sg);
  82
  83 void
  84 drm_clflush_virt_range(void *in_addr, unsigned long length)
  85 {
  86         char *addr = in_addr;
  87
  88         if (cpu_has_clflush) {
  89                 const int size = cpu_clflush_line_size;
  90                 char *end = addr + length;
  91                 addr = (void *)(((unsigned long)addr) & -size);
  92                 mb();
  93                 for (; addr < end; addr += size)
  94                         clflush((unsigned long)addr);
  95                 mb();
  96                 return;
  97         }
  98
  99         cpu_wbinvd_on_all_cpus();
 100 }
 101 EXPORT_SYMBOL(drm_clflush_virt_range);