linux/arch/sh64/kernel/pci-dma.c

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/*
* Copyright (C) 2001 David J. Mckay (david.mckay@st.com)
* Copyright (C) 2003 Paul Mundt (lethal@linux-sh.org)
*
* May be copied or modified under the terms of the GNU General Public
* License. See linux/COPYING for more information.
*
* Dynamic DMA mapping support.
*/
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/pci.h>
#include <asm/io.h>
void *consistent_alloc(struct pci_dev *hwdev, size_t size,
dma_addr_t *dma_handle)
{
void *ret;
int gfp = GFP_ATOMIC;
void *vp;
if (hwdev == NULL || hwdev->dma_mask != 0xffffffff)
gfp |= GFP_DMA;
ret = (void *)__get_free_pages(gfp, get_order(size));
/* now call our friend ioremap_nocache to give us an uncached area */
vp = ioremap_nocache(virt_to_phys(ret), size);
if (vp != NULL) {
memset(vp, 0, size);
*dma_handle = virt_to_bus(ret);
dma_cache_wback_inv((unsigned long)ret, size);
}
return vp;
}
void consistent_free(struct pci_dev *hwdev, size_t size,
void *vaddr, dma_addr_t dma_handle)
{
void *alloc;
alloc = bus_to_virt((unsigned long)dma_handle);
free_pages((unsigned long)alloc, get_order(size));
iounmap(vaddr);
}