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-noncoherent.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/pgalloc.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 arch_dma_mmap_pgprot(struct device *dev, pgprot_t prot,
  27                 unsigned long attrs)
  28 {
  29         if (CPU_IS_040_OR_060) {
  30                 pgprot_val(prot) &= ~_PAGE_CACHE040;
  31                 pgprot_val(prot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S;
  32         } else {
  33                 pgprot_val(prot) |= _PAGE_NOCACHE030;
  34         }
  35         return prot;
  36 }
  37 #else
  38
  39 #include <asm/cacheflush.h>
  40
  41 void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
  42                 gfp_t gfp, unsigned long attrs)
  43 {
  44         void *ret;
  45
  46         if (dev == NULL || (*dev->dma_mask < 0xffffffff))
  47                 gfp |= GFP_DMA;
  48         ret = (void *)__get_free_pages(gfp, get_order(size));
  49
  50         if (ret != NULL) {
  51                 memset(ret, 0, size);
  52                 *dma_handle = virt_to_phys(ret);
  53         }
  54         return ret;
  55 }
  56
  57 void arch_dma_free(struct device *dev, size_t size, void *vaddr,
  58                 dma_addr_t dma_handle, unsigned long attrs)
  59 {
  60         free_pages((unsigned long)vaddr, get_order(size));
  61 }
  62
  63 #endif /* CONFIG_MMU && !CONFIG_COLDFIRE */
  64
  65 void arch_sync_dma_for_device(struct device *dev, phys_addr_t handle,
  66                 size_t size, enum dma_data_direction dir)
  67 {
  68         switch (dir) {
  69         case DMA_BIDIRECTIONAL:
  70         case DMA_TO_DEVICE:
  71                 cache_push(handle, size);
  72                 break;
  73         case DMA_FROM_DEVICE:
  74                 cache_clear(handle, size);
  75                 break;
  76         default:
  77                 pr_err_ratelimited("dma_sync_single_for_device: unsupported dir %u\n",
  78                                    dir);
  79                 break;
  80         }
  81 }