pci-dma.c

上传linux-jx2410的源代码

/*
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2000  Ani Joshi <[e-mail]>
 * Copyright (C) 2000, 2001  Ralf Baechle <[e-mail]>
 * swiped from i386, and cloned for MIPS by Geert, polished by Ralf.
 */
#include <linux/config.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/pci.h>

#include <asm/io.h>

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

	if (hwdev == NULL || hwdev->dma_mask != 0xffffffff)
		gfp |= GFP_DMA;
	ret = (void *) __get_free_pages(gfp, get_order(size));

	if (ret != NULL) {
		memset(ret, 0, size);
#ifndef CONFIG_COHERENT_IO
		dma_cache_wback_inv((unsigned long) ret, size);
		ret = KSEG1ADDR(ret);
#endif
		*dma_handle = virt_to_bus(ret);
	}

	return ret;
}

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

#ifndef CONFIG_COHERENT_IO
	addr = KSEG0ADDR(addr);
#endif
	free_pages(addr, get_order(size));
}