pci-dma.c

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/* 
 * Copyright (C) 2001 David J. Mckay ([e-mail])
 *
 * 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>
#include <asm/addrspace.h>


void *pci_alloc_consistent(struct pci_dev *hwdev, size_t size,
			   dma_addr_t * dma_handle)
{
	void *ret;
	int gfp = GFP_ATOMIC;

	ret = (void *) __get_free_pages(gfp, get_order(size));

	if (ret != NULL) {
	        /* Is it neccessary to do the memset? */
		memset(ret, 0, size);
		*dma_handle = virt_to_bus(ret);
	}
	/* We must flush the cache before we pass it on to the device */
	dma_cache_wback_inv(ret, size);
	return  P2SEGADDR(ret);
}

void pci_free_consistent(struct pci_dev *hwdev, size_t size,
			 void *vaddr, dma_addr_t dma_handle)
{
        unsigned long p1addr=P1SEGADDR((unsigned long)vaddr);

	free_pages(p1addr, get_order(size));
}