50 lines
1.1 KiB
C
50 lines
1.1 KiB
C
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/*
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* Dynamic DMA mapping support.
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*
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* On cris there is no hardware dynamic DMA address translation,
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* so consistent alloc/free are merely page allocation/freeing.
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* The rest of the dynamic DMA mapping interface is implemented
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* in asm/pci.h.
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*
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* Borrowed from i386.
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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 <linux/pci.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, gfp_t gfp)
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{
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void *ret;
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int order = get_order(size);
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/* ignore region specifiers */
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gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
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if (dma_alloc_from_coherent(dev, size, dma_handle, &ret))
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return ret;
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if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
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gfp |= GFP_DMA;
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ret = (void *)__get_free_pages(gfp, order);
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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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int order = get_order(size);
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if (!dma_release_from_coherent(dev, order, vaddr))
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free_pages((unsigned long)vaddr, order);
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}
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