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Diffstat (limited to 'arch/mn10300/include/asm/dma-mapping.h')
-rw-r--r-- | arch/mn10300/include/asm/dma-mapping.h | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/arch/mn10300/include/asm/dma-mapping.h b/arch/mn10300/include/asm/dma-mapping.h new file mode 100644 index 00000000000..ccae8f6c632 --- /dev/null +++ b/arch/mn10300/include/asm/dma-mapping.h @@ -0,0 +1,234 @@ +/* DMA mapping routines for the MN10300 arch + * + * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public Licence + * as published by the Free Software Foundation; either version + * 2 of the Licence, or (at your option) any later version. + */ +#ifndef _ASM_DMA_MAPPING_H +#define _ASM_DMA_MAPPING_H + +#include <linux/mm.h> +#include <linux/scatterlist.h> + +#include <asm/cache.h> +#include <asm/io.h> + +extern void *dma_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, int flag); + +extern void dma_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_handle); + +#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)) + +/* + * Map a single buffer of the indicated size for DMA in streaming mode. The + * 32-bit bus address to use is returned. + * + * Once the device is given the dma address, the device owns this memory until + * either pci_unmap_single or pci_dma_sync_single is performed. + */ +static inline +dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size, + enum dma_data_direction direction) +{ + BUG_ON(direction == DMA_NONE); + mn10300_dcache_flush_inv(); + return virt_to_bus(ptr); +} + +/* + * Unmap a single streaming mode DMA translation. The dma_addr and size must + * match what was provided for in a previous pci_map_single call. All other + * usages are undefined. + * + * After this call, reads by the cpu to the buffer are guarenteed to see + * whatever the device wrote there. + */ +static inline +void dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size, + enum dma_data_direction direction) +{ + BUG_ON(direction == DMA_NONE); +} + +/* + * Map a set of buffers described by scatterlist in streaming mode for DMA. + * This is the scather-gather version of the above pci_map_single interface. + * Here the scatter gather list elements are each tagged with the appropriate + * dma address and length. They are obtained via sg_dma_{address,length}(SG). + * + * NOTE: An implementation may be able to use a smaller number of DMA + * address/length pairs than there are SG table elements. (for example + * via virtual mapping capabilities) The routine returns the number of + * addr/length pairs actually used, at most nents. + * + * Device ownership issues as mentioned above for pci_map_single are the same + * here. + */ +static inline +int dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents, + enum dma_data_direction direction) +{ + struct scatterlist *sg; + int i; + + BUG_ON(!valid_dma_direction(direction)); + WARN_ON(nents == 0 || sglist[0].length == 0); + + for_each_sg(sglist, sg, nents, i) { + BUG_ON(!sg_page(sg)); + + sg->dma_address = sg_phys(sg); + } + + mn10300_dcache_flush_inv(); + return nents; +} + +/* + * Unmap a set of streaming mode DMA translations. + * Again, cpu read rules concerning calls here are the same as for + * pci_unmap_single() above. + */ +static inline +void dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nhwentries, + enum dma_data_direction direction) +{ + BUG_ON(!valid_dma_direction(direction)); +} + +/* + * pci_{map,unmap}_single_page maps a kernel page to a dma_addr_t. identical + * to pci_map_single, but takes a struct page instead of a virtual address + */ +static inline +dma_addr_t dma_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction direction) +{ + BUG_ON(direction == DMA_NONE); + return page_to_bus(page) + offset; +} + +static inline +void dma_unmap_page(struct device *dev, dma_addr_t dma_address, size_t size, + enum dma_data_direction direction) +{ + BUG_ON(direction == DMA_NONE); +} + +/* + * Make physical memory consistent for a single streaming mode DMA translation + * after a transfer. + * + * If you perform a pci_map_single() but wish to interrogate the buffer using + * the cpu, yet do not wish to teardown the PCI dma mapping, you must call this + * function before doing so. At the next point you give the PCI dma address + * back to the card, the device again owns the buffer. + */ +static inline +void dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, + size_t size, enum dma_data_direction direction) +{ +} + +static inline +void dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle, + size_t size, enum dma_data_direction direction) +{ + mn10300_dcache_flush_inv(); +} + +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 direction) +{ +} + +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 direction) +{ + mn10300_dcache_flush_inv(); +} + + +/* + * Make physical memory consistent for a set of streaming mode DMA translations + * after a transfer. + * + * The same as pci_dma_sync_single but for a scatter-gather list, same rules + * and usage. + */ +static inline +void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, + int nelems, enum dma_data_direction direction) +{ +} + +static inline +void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, + int nelems, enum dma_data_direction direction) +{ + mn10300_dcache_flush_inv(); +} + +static inline +int dma_mapping_error(struct device *dev, dma_addr_t dma_addr) +{ + return 0; +} + +/* + * Return whether the given PCI device DMA address mask can be supported + * properly. For example, if your device can only drive the low 24-bits during + * PCI bus mastering, then you would pass 0x00ffffff as the mask to this + * function. + */ +static inline +int dma_supported(struct device *dev, u64 mask) +{ + /* + * we fall back to GFP_DMA when the mask isn't all 1s, so we can't + * guarantee allocations that must be within a tighter range than + * GFP_DMA + */ + if (mask < 0x00ffffff) + return 0; + return 1; +} + +static inline +int dma_set_mask(struct device *dev, u64 mask) +{ + if (!dev->dma_mask || !dma_supported(dev, mask)) + return -EIO; + + *dev->dma_mask = mask; + return 0; +} + +static inline +int dma_get_cache_alignment(void) +{ + return 1 << L1_CACHE_SHIFT; +} + +#define dma_is_consistent(d) (1) + +static inline +void dma_cache_sync(void *vaddr, size_t size, + enum dma_data_direction direction) +{ + mn10300_dcache_flush_inv(); +} + +#endif |