arch/m68knommu/kernel/dma.c

   1 /*
   2  * Dynamic DMA mapping support.
   3  *
   4  * We never have any address translations to worry about, so this
   5  * is just alloc/free.
   6  */
   7
   8 #include <linux/types.h>
   9 #include <linux/mm.h>
  10 #include <linux/string.h>
  11 #include <linux/device.h>
  12 #include <asm/io.h>
  13
  14 void *dma_alloc_coherent(struct device *dev, size_t size,
  15                            dma_addr_t *dma_handle, int gfp)
  16 {
  17         void *ret;
  18         /* ignore region specifiers */
  19         gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
  20
  21         if (dev == NULL || (*dev->dma_mask < 0xffffffff))
  22                 gfp |= GFP_DMA;
  23         ret = (void *)__get_free_pages(gfp, get_order(size));
  24
  25         if (ret != NULL) {
  26                 memset(ret, 0, size);
  27                 *dma_handle = virt_to_phys(ret);
  28         }
  29         return ret;
  30 }
  31
  32 void dma_free_coherent(struct device *dev, size_t size,
  33                          void *vaddr, dma_addr_t dma_handle)
  34 {
  35         free_pages((unsigned long)vaddr, get_order(size));
  36 }