arc-linux-uclibc/include/asm/dma-mapping.h

/*
 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Vineetg: Feb 2008
 *  -Seperated DMA <=>  PHY into Platform specific files
 *   Reason being ARC PCI Host Bridge can't support DMA addr = 0
 *   which is the default Bus address generated by code.
 *   while other Host Bridges may do
 *
 * Vineetg: Jan 2009
 *  -Brand new DMA Mapping API implementation
 *  -Borrowed a lot from ARM/MIPS
 */

#ifndef ASMARC_DMA_MAPPING_H
#define ASMARC_DMA_MAPPING_H

#include <linux/scatterlist.h>
#include <linux/vmalloc.h>
#include <asm/cacheflush.h>
#include <asm/io.h>
#include <plat_dma_addr.h>  // Baord specific DMA <=> PHY translation

extern void * dma_alloc_coherent(struct device *dev, size_t size,
                    dma_addr_t *dma_handle, gfp_t flag);
extern void dma_free_coherent(struct device *dev, size_t size, void *kvaddr,
                    dma_addr_t dma_handle);

//#define _dma_cache_maint(a,b,c) __dma_cache_maint(a,b,c,current_text_addr())
#define _dma_cache_maint(a,b,c) __dma_cache_maint(a,b,c,0)

extern void __dma_cache_maint(void *start, size_t sz, int dir, void *caller);


/*******************************************************************
 * Streaming DMA Mapping APIs:
 */

static inline dma_addr_t
dma_map_single(struct device *dev, void *cpu_addr, size_t size,
                enum dma_data_direction dir)
{
    _dma_cache_maint(cpu_addr, size, dir);
    return plat_kernel_addr_to_dma(dev,cpu_addr);
}

static inline void
dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
                    enum dma_data_direction dir)
{
    /*Nothing to do*/
}

static inline int
dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
           enum dma_data_direction dir)
{
    int i;

    for (i = 0; i < nents; i++, sg++ ) {
        sg->dma_address = plat_kernel_addr_to_dma(dev,sg_virt(sg));
        _dma_cache_maint(sg_virt(sg), sg->length, dir);
    }

    return nents;
}

static inline void
dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nhwentries,
                enum dma_data_direction dir)
{
    /*Nothing to do*/
}


static inline dma_addr_t
dma_map_page(struct device *dev, struct page *page,
            unsigned long offset, size_t size,
            enum dma_data_direction dir)
{
    return dma_map_single(dev, page_address(page) + offset, size, dir);
}

static inline void
dma_unmap_page(struct device *dev, dma_addr_t dma_address, size_t size,
           enum dma_data_direction dir)
{
    /*Nothing to do*/
}

static inline void
dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, size_t size,
                        enum dma_data_direction dir)
{
    _dma_cache_maint((void *)plat_dma_addr_to_kernel(dev,dma_handle), size, dir);
}

static inline void
dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle,
                            size_t size, enum dma_data_direction dir)
{
    _dma_cache_maint((void *)plat_dma_addr_to_kernel(dev,dma_handle), size, dir);
}

static inline void
dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nelems,
                    enum dma_data_direction dir)
{
    int i;

    for (i = 0; i < nelems; i++, sg++ ) {
        _dma_cache_maint(sg_virt(sg), sg->length, dir);
    }
}

static inline void
dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nelems,
                        enum dma_data_direction dir)
{
    int i;

    for (i = 0; i < nelems; i++, sg++ ) {
        _dma_cache_maint(sg_virt(sg), sg->length, dir);
    }
}

#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
#define dma_is_consistent(d, h) (1)

static inline void
dma_sync_single_range_for_cpu(struct device *dev, dma_addr_t dma_handle,
                  unsigned long offset, size_t size,
                  enum dma_data_direction dir)
{
    dma_sync_single_for_cpu(dev, dma_handle+offset,
                                size, dir);
}

static inline void
dma_sync_single_range_for_device(struct device *dev, dma_addr_t dma_handle,
                 unsigned long offset, size_t size,
                 enum dma_data_direction dir)
{
    dma_sync_single_for_device(dev, dma_handle+offset,
                                size, dir);
}

static inline void
dma_cache_sync(struct device *dev, void *vaddr, size_t size,
                enum dma_data_direction dir)
{
    _dma_cache_maint(vaddr, size, dir);
}

static inline int
dma_error(dma_addr_t dma_addr)
{
    return 0;
}

static inline int
dma_supported(struct device *dev, u64 mask)
{
    return 1;
}

static inline int
dma_set_mask(struct device *dev, u64 dma_mask)
{
	if (!dev->dma_mask || !dma_supported(dev, dma_mask))
		return -EIO;

	*dev->dma_mask = dma_mask;

	return 0;
}

static inline int
dma_get_cache_alignment(void)
{
    return (L1_CACHE_BYTES);
}

static inline int
dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
{
    BUG();
    return 0;
}

#endif