51 строка
1.2 KiB
C
51 строка
1.2 KiB
C
/*
|
|
* 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_phys(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 = phys_to_virt((unsigned long)dma_handle);
|
|
free_pages((unsigned long)alloc, get_order(size));
|
|
|
|
iounmap(vaddr);
|
|
}
|
|
|