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/*
* linux/include/asm-arm/proc-armv/io.h
*/
/*
* The caches on some architectures aren't dma-coherent and have need to
* handle this in software. There are two types of operations that
* can be applied to dma buffers.
*
* - dma_cache_wback_inv(start, size) makes caches and RAM coherent by
* writing the content of the caches back to memory, if necessary.
* The function also invalidates the affected part of the caches as
* necessary before DMA transfers from outside to memory.
* - dma_cache_inv(start, size) invalidates the affected parts of the
* caches. Dirty lines of the caches may be written back or simply
* be discarded. This operation is necessary before dma operations
* to the memory.
* - dma_cache_wback(start, size) writes back any dirty lines but does
* not invalidate the cache. This can be used before DMA reads from
* memory,
*/
#include <asm/proc-fns.h>
extern inline void dma_cache_inv(unsigned long start, unsigned long size)
{
processor.u.armv3v4._cache_purge_area(start, start + size);
}
extern inline void dma_cache_wback(unsigned long start, unsigned long size)
{
processor.u.armv3v4._cache_wback_area(start, start + size);
}
extern inline void dma_cache_wback_inv(unsigned long start, unsigned long size)
{
processor.u.armv3v4._flush_cache_area(start, start + size, 0);
}
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