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79 lines
2.7 KiB
C
79 lines
2.7 KiB
C
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/*
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* DMA region bookkeeping routines
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*
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* Copyright (C) 2002 Maas Digital LLC
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*
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* This code is licensed under the GPL. See the file COPYING in the root
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* directory of the kernel sources for details.
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*/
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#ifndef IEEE1394_DMA_H
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#define IEEE1394_DMA_H
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#include <linux/pci.h>
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#include <asm/scatterlist.h>
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/* struct dma_prog_region
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a small, physically-contiguous DMA buffer with random-access,
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synchronous usage characteristics
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*/
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struct dma_prog_region {
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unsigned char *kvirt; /* kernel virtual address */
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struct pci_dev *dev; /* PCI device */
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unsigned int n_pages; /* # of kernel pages */
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dma_addr_t bus_addr; /* base bus address */
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};
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/* clear out all fields but do not allocate any memory */
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void dma_prog_region_init(struct dma_prog_region *prog);
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int dma_prog_region_alloc(struct dma_prog_region *prog, unsigned long n_bytes, struct pci_dev *dev);
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void dma_prog_region_free(struct dma_prog_region *prog);
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static inline dma_addr_t dma_prog_region_offset_to_bus(struct dma_prog_region *prog, unsigned long offset)
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{
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return prog->bus_addr + offset;
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}
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/* struct dma_region
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a large, non-physically-contiguous DMA buffer with streaming,
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asynchronous usage characteristics
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*/
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struct dma_region {
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unsigned char *kvirt; /* kernel virtual address */
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struct pci_dev *dev; /* PCI device */
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unsigned int n_pages; /* # of kernel pages */
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unsigned int n_dma_pages; /* # of IOMMU pages */
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struct scatterlist *sglist; /* IOMMU mapping */
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int direction; /* PCI_DMA_TODEVICE, etc */
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};
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/* clear out all fields but do not allocate anything */
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void dma_region_init(struct dma_region *dma);
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/* allocate the buffer and map it to the IOMMU */
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int dma_region_alloc(struct dma_region *dma, unsigned long n_bytes, struct pci_dev *dev, int direction);
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/* unmap and free the buffer */
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void dma_region_free(struct dma_region *dma);
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/* sync the CPU's view of the buffer */
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void dma_region_sync_for_cpu(struct dma_region *dma, unsigned long offset, unsigned long len);
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/* sync the IO bus' view of the buffer */
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void dma_region_sync_for_device(struct dma_region *dma, unsigned long offset, unsigned long len);
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/* map the buffer into a user space process */
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int dma_region_mmap(struct dma_region *dma, struct file *file, struct vm_area_struct *vma);
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/* macro to index into a DMA region (or dma_prog_region) */
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#define dma_region_i(_dma, _type, _index) ( ((_type*) ((_dma)->kvirt)) + (_index) )
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/* return the DMA bus address of the byte with the given offset
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relative to the beginning of the dma_region */
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dma_addr_t dma_region_offset_to_bus(struct dma_region *dma, unsigned long offset);
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#endif /* IEEE1394_DMA_H */
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