target/linux/ubicom32/files/arch/ubicom32/kernel/dma.c

   1 /*
   2  * arch/ubicom32/kernel/dma.c
   3  *   Ubicom32 architecture dynamic DMA mapping support.
   4  *
   5  * (C) Copyright 2009, Ubicom, Inc.
   6  *
   7  * This file is part of the Ubicom32 Linux Kernel Port.
   8  *
   9  * The Ubicom32 Linux Kernel Port is free software: you can redistribute
  10  * it and/or modify it under the terms of the GNU General Public License
  11  * as published by the Free Software Foundation, either version 2 of the
  12  * License, or (at your option) any later version.
  13  *
  14  * The Ubicom32 Linux Kernel Port is distributed in the hope that it
  15  * will be useful, but WITHOUT ANY WARRANTY; without even the implied
  16  * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  17  * the GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with the Ubicom32 Linux Kernel Port.  If not,
  21  * see <http://www.gnu.org/licenses/>.
  22  *
  23  * Ubicom32 implementation derived from (with many thanks):
  24  *   arch/m68knommu
  25  *   arch/blackfin
  26  *   arch/parisc
  27  *
  28  * We never have any address translations to worry about, so this
  29  * is just alloc/free.
  30  */
  31
  32 #include <linux/types.h>
  33 #include <linux/mm.h>
  34 #include <linux/string.h>
  35 #include <linux/device.h>
  36 #include <linux/io.h>
  37
  38 void *dma_alloc_coherent(struct device *dev, size_t size,
  39                            dma_addr_t *dma_handle, int gfp)
  40 {
  41         void *ret;
  42         /* ignore region specifiers */
  43         gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
  44
  45         if (dev == NULL || (*dev->dma_mask < 0xffffffff))
  46                 gfp |= GFP_DMA;
  47         ret = (void *)__get_free_pages(gfp, get_order(size));
  48
  49         if (ret != NULL) {
  50                 memset(ret, 0, size);
  51                 *dma_handle = virt_to_phys(ret);
  52         }
  53         return ret;
  54 }
  55
  56 void dma_free_coherent(struct device *dev, size_t size,
  57                          void *vaddr, dma_addr_t dma_handle)
  58 {
  59         free_pages((unsigned long)vaddr, get_order(size));
  60 }