LXR linux-old/arch/sh/overdrive/pcidma.c

   1/* 
   2 * Copyright (C) 2000 David J. Mckay (david.mckay@st.com)
   3 *
   4 * May be copied or modified under the terms of the GNU General Public
   5 * License.  See linux/COPYING for more information.                            
   6 *
   7 * Dynamic DMA mapping support.
   8 *
   9 * On the overdrive, we can only DMA from memory behind the PCI bus!
  10 * this means that all DMA'able memory must come from there. 
  11 * this restriction will not apply to later boards.
  12 */
  13
  14#include <linux/types.h>
  15#include <linux/mm.h>
  16#include <linux/string.h>
  17#include <linux/pci.h>
  18#include <asm/io.h>
  19
  20void *pci_alloc_consistent(struct pci_dev *hwdev, size_t size,
  21                           dma_addr_t * dma_handle)
  22{
  23        void *ret;
  24        int gfp = GFP_ATOMIC;
  25
  26        printk("BUG: pci_alloc_consistent() called - not yet supported\n");
  27        /* We ALWAYS need DMA memory on the overdrive hardware,
  28         * due to it's extreme wierdness
  29         * Need to flush the cache here as well, since the memory
  30         * can still be seen through the cache!
  31         */
  32        gfp |= GFP_DMA;
  33        ret = (void *) __get_free_pages(gfp, get_order(size));
  34
  35        if (ret != NULL) {
  36                memset(ret, 0, size);
  37                *dma_handle = virt_to_bus(ret);
  38        }
  39        return ret;
  40}
  41
  42void pci_free_consistent(struct pci_dev *hwdev, size_t size,
  43                         void *vaddr, dma_addr_t dma_handle)
  44{
  45        free_pages((unsigned long) vaddr, get_order(size));
  46}
  47