36 lines
783 B
C
36 lines
783 B
C
/*
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* Dynamic DMA mapping support.
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*
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* We never have any address translations to worry about, so this
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* is just alloc/free.
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*/
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#include <linux/types.h>
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#include <linux/mm.h>
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#include <linux/string.h>
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#include <asm/io.h>
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void *dma_alloc_coherent(struct device *dev, size_t size,
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dma_addr_t *dma_handle, int gfp)
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{
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void *ret;
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/* ignore region specifiers */
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gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
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if (dev == NULL || (*dev->dma_mask < 0xffffffff))
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gfp |= GFP_DMA;
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ret = (void *)__get_free_pages(gfp, get_order(size));
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if (ret != NULL) {
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memset(ret, 0, size);
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*dma_handle = virt_to_phys(ret);
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}
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return ret;
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}
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void dma_free_coherent(struct device *dev, size_t size,
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void *vaddr, dma_addr_t dma_handle)
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{
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free_pages((unsigned long)vaddr, get_order(size));
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}
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