arch/m68k/kernel/dma.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file COPYING in the main directory of this archive
   4  * for more details.
   5  */
   6
   7 #undef DEBUG
   8
   9 #include <linux/dma-map-ops.h>
  10 #include <linux/device.h>
  11 #include <linux/kernel.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/scatterlist.h>
  14 #include <linux/slab.h>
  15 #include <linux/vmalloc.h>
  16 #include <linux/export.h>
  17
  18 #include <asm/cacheflush.h>
  19
  20 #if defined(CONFIG_MMU) && !defined(CONFIG_COLDFIRE)
  21 void arch_dma_prep_coherent(struct page *page, size_t size)
  22 {
  23         cache_push(page_to_phys(page), size);
  24 }
  25
  26 pgprot_t pgprot_dmacoherent(pgprot_t prot)
  27 {
  28         if (CPU_IS_040_OR_060) {
  29                 pgprot_val(prot) &= ~_PAGE_CACHE040;
  30                 pgprot_val(prot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S;
  31         } else {
  32                 pgprot_val(prot) |= _PAGE_NOCACHE030;
  33         }
  34         return prot;
  35 }
  36 #else
  37 void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
  38                 gfp_t gfp, unsigned long attrs)
  39 {
  40         void *ret;
  41
  42         if (dev == NULL || (*dev->dma_mask < 0xffffffff))
  43                 gfp |= GFP_DMA;
  44         ret = (void *)__get_free_pages(gfp, get_order(size));
  45
  46         if (ret != NULL) {
  47                 memset(ret, 0, size);
  48                 *dma_handle = virt_to_phys(ret);
  49         }
  50         return ret;
  51 }
  52
  53 void arch_dma_free(struct device *dev, size_t size, void *vaddr,
  54                 dma_addr_t dma_handle, unsigned long attrs)
  55 {
  56         free_pages((unsigned long)vaddr, get_order(size));
  57 }
  58
  59 #endif /* CONFIG_MMU && !CONFIG_COLDFIRE */
  60
  61 void arch_sync_dma_for_device(phys_addr_t handle, size_t size,
  62                 enum dma_data_direction dir)
  63 {
  64         switch (dir) {
  65         case DMA_BIDIRECTIONAL:
  66         case DMA_TO_DEVICE:
  67                 cache_push(handle, size);
  68                 break;
  69         case DMA_FROM_DEVICE:
  70                 cache_clear(handle, size);
  71                 break;
  72         default:
  73                 pr_err_ratelimited("dma_sync_single_for_device: unsupported dir %u\n",
  74                                    dir);
  75                 break;
  76         }
  77 }