pci-dma.c

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/* pci-dma.c: Dynamic DMA mapping support for the FRV CPUs that have MMUs
 *
 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells ([email protected])
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#include <linux/types.h>
#include <linux/dma-mapping.h>
#include <linux/list.h>
#include <linux/pci.h>
#include <linux/export.h>
#include <linux/highmem.h>
#include <linux/scatterlist.h>
#include <asm/io.h>

void *dma_alloc_coherent(struct device *hwdev, size_t size, dma_addr_t *dma_handle, gfp_t gfp)
{
    void *ret;

    ret = consistent_alloc(gfp, size, dma_handle);
    if (ret)
        memset(ret, 0, size);

    return ret;
}

EXPORT_SYMBOL(dma_alloc_coherent);

void dma_free_coherent(struct device *hwdev, size_t size, void *vaddr, dma_addr_t dma_handle)
{
    consistent_free(vaddr);
}

EXPORT_SYMBOL(dma_free_coherent);

dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
              enum dma_data_direction direction)
{
    BUG_ON(direction == DMA_NONE);

    frv_cache_wback_inv((unsigned long) ptr, (unsigned long) ptr + size);

    return virt_to_bus(ptr);
}

EXPORT_SYMBOL(dma_map_single);

int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
           enum dma_data_direction direction)
{
    unsigned long dampr2;
    void *vaddr;
    int i;

    BUG_ON(direction == DMA_NONE);

    dampr2 = __get_DAMPR(2);

    for (i = 0; i < nents; i++) {
        vaddr = kmap_atomic_primary(sg_page(&sg[i]));

        frv_dcache_writeback((unsigned long) vaddr,
                     (unsigned long) vaddr + PAGE_SIZE);

    }

    kunmap_atomic_primary(vaddr);
    if (dampr2) {
        __set_DAMPR(2, dampr2);
        __set_IAMPR(2, dampr2);
    }

    return nents;
}

EXPORT_SYMBOL(dma_map_sg);

dma_addr_t dma_map_page(struct device *dev, struct page *page, unsigned long offset,
            size_t size, enum dma_data_direction direction)
{
    BUG_ON(direction == DMA_NONE);
    flush_dcache_page(page);
    return (dma_addr_t) page_to_phys(page) + offset;
}

EXPORT_SYMBOL(dma_map_page);