arch/h8300/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 #include <linux/dma-mapping.h>
   8 #include <linux/kernel.h>
   9 #include <linux/scatterlist.h>
  10 #include <linux/module.h>
  11 #include <asm/pgalloc.h>
  12
  13 static void *dma_alloc(struct device *dev, size_t size,
  14                        dma_addr_t *dma_handle, gfp_t gfp,
  15                        struct dma_attrs *attrs)
  16 {
  17         void *ret;
  18
  19         /* ignore region specifiers */
  20         gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
  21
  22         if (dev == NULL || (*dev->dma_mask < 0xffffffff))
  23                 gfp |= GFP_DMA;
  24         ret = (void *)__get_free_pages(gfp, get_order(size));
  25
  26         if (ret != NULL) {
  27                 memset(ret, 0, size);
  28                 *dma_handle = virt_to_phys(ret);
  29         }
  30         return ret;
  31 }
  32
  33 static void dma_free(struct device *dev, size_t size,
  34                      void *vaddr, dma_addr_t dma_handle,
  35                      struct dma_attrs *attrs)
  36
  37 {
  38         free_pages((unsigned long)vaddr, get_order(size));
  39 }
  40
  41 static dma_addr_t map_page(struct device *dev, struct page *page,
  42                                   unsigned long offset, size_t size,
  43                                   enum dma_data_direction direction,
  44                                   struct dma_attrs *attrs)
  45 {
  46         return page_to_phys(page) + offset;
  47 }
  48
  49 static int map_sg(struct device *dev, struct scatterlist *sgl,
  50                   int nents, enum dma_data_direction direction,
  51                   struct dma_attrs *attrs)
  52 {
  53         struct scatterlist *sg;
  54         int i;
  55
  56         for_each_sg(sgl, sg, nents, i) {
  57                 sg->dma_address = sg_phys(sg);
  58         }
  59
  60         return nents;
  61 }
  62
  63 struct dma_map_ops h8300_dma_map_ops = {
  64         .alloc = dma_alloc,
  65         .free = dma_free,
  66         .map_page = map_page,
  67         .map_sg = map_sg,
  68 };
  69 EXPORT_SYMBOL(h8300_dma_map_ops);