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author | Becky Bruce <becky.bruce@freescale.com> | 2008-09-08 11:09:52 +0200 |
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committer | Kumar Gala <galak@kernel.crashing.org> | 2008-09-24 23:26:41 +0200 |
commit | 7c05d7e08d907d66b8e18515572f42c71fb709fe (patch) | |
tree | 6f5c6549f6d515c38a0ece662da4ae1f1ec43579 /arch/powerpc/kernel/dma.c | |
parent | Merge branch 'powerpc-next' of master.kernel.org:/pub/scm/linux/kernel/git/ga... (diff) | |
download | linux-7c05d7e08d907d66b8e18515572f42c71fb709fe.tar.xz linux-7c05d7e08d907d66b8e18515572f42c71fb709fe.zip |
powerpc: Rename dma_64.c to dma.c
This is in preparation for the merge of the 32 and 64-bit
dma code in arch/powerpc.
Signed-off-by: Becky Bruce <becky.bruce@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Diffstat (limited to 'arch/powerpc/kernel/dma.c')
-rw-r--r-- | arch/powerpc/kernel/dma.c | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c new file mode 100644 index 000000000000..ae5708e3a312 --- /dev/null +++ b/arch/powerpc/kernel/dma.c @@ -0,0 +1,200 @@ +/* + * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corporation + * + * Provide default implementations of the DMA mapping callbacks for + * directly mapped busses and busses using the iommu infrastructure + */ + +#include <linux/device.h> +#include <linux/dma-mapping.h> +#include <asm/bug.h> +#include <asm/iommu.h> +#include <asm/abs_addr.h> + +/* + * Generic iommu implementation + */ + +/* Allocates a contiguous real buffer and creates mappings over it. + * Returns the virtual address of the buffer and sets dma_handle + * to the dma address (mapping) of the first page. + */ +static void *dma_iommu_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t flag) +{ + return iommu_alloc_coherent(dev, dev->archdata.dma_data, size, + dma_handle, device_to_mask(dev), flag, + dev->archdata.numa_node); +} + +static void dma_iommu_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_handle) +{ + iommu_free_coherent(dev->archdata.dma_data, size, vaddr, dma_handle); +} + +/* Creates TCEs for a user provided buffer. The user buffer must be + * contiguous real kernel storage (not vmalloc). The address of the buffer + * passed here is the kernel (virtual) address of the buffer. The buffer + * need not be page aligned, the dma_addr_t returned will point to the same + * byte within the page as vaddr. + */ +static dma_addr_t dma_iommu_map_single(struct device *dev, void *vaddr, + size_t size, + enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + return iommu_map_single(dev, dev->archdata.dma_data, vaddr, size, + device_to_mask(dev), direction, attrs); +} + + +static void dma_iommu_unmap_single(struct device *dev, dma_addr_t dma_handle, + size_t size, + enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + iommu_unmap_single(dev->archdata.dma_data, dma_handle, size, direction, + attrs); +} + + +static int dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist, + int nelems, enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + return iommu_map_sg(dev, dev->archdata.dma_data, sglist, nelems, + device_to_mask(dev), direction, attrs); +} + +static void dma_iommu_unmap_sg(struct device *dev, struct scatterlist *sglist, + int nelems, enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + iommu_unmap_sg(dev->archdata.dma_data, sglist, nelems, direction, + attrs); +} + +/* We support DMA to/from any memory page via the iommu */ +static int dma_iommu_dma_supported(struct device *dev, u64 mask) +{ + struct iommu_table *tbl = dev->archdata.dma_data; + + if (!tbl || tbl->it_offset > mask) { + printk(KERN_INFO + "Warning: IOMMU offset too big for device mask\n"); + if (tbl) + printk(KERN_INFO + "mask: 0x%08lx, table offset: 0x%08lx\n", + mask, tbl->it_offset); + else + printk(KERN_INFO "mask: 0x%08lx, table unavailable\n", + mask); + return 0; + } else + return 1; +} + +struct dma_mapping_ops dma_iommu_ops = { + .alloc_coherent = dma_iommu_alloc_coherent, + .free_coherent = dma_iommu_free_coherent, + .map_single = dma_iommu_map_single, + .unmap_single = dma_iommu_unmap_single, + .map_sg = dma_iommu_map_sg, + .unmap_sg = dma_iommu_unmap_sg, + .dma_supported = dma_iommu_dma_supported, +}; +EXPORT_SYMBOL(dma_iommu_ops); + +/* + * Generic direct DMA implementation + * + * This implementation supports a per-device offset that can be applied if + * the address at which memory is visible to devices is not 0. Platform code + * can set archdata.dma_data to an unsigned long holding the offset. By + * default the offset is zero. + */ + +static unsigned long get_dma_direct_offset(struct device *dev) +{ + return (unsigned long)dev->archdata.dma_data; +} + +static void *dma_direct_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t flag) +{ + struct page *page; + void *ret; + int node = dev->archdata.numa_node; + + page = alloc_pages_node(node, flag, get_order(size)); + if (page == NULL) + return NULL; + ret = page_address(page); + memset(ret, 0, size); + *dma_handle = virt_to_abs(ret) + get_dma_direct_offset(dev); + + return ret; +} + +static void dma_direct_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_handle) +{ + free_pages((unsigned long)vaddr, get_order(size)); +} + +static dma_addr_t dma_direct_map_single(struct device *dev, void *ptr, + size_t size, + enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + return virt_to_abs(ptr) + get_dma_direct_offset(dev); +} + +static void dma_direct_unmap_single(struct device *dev, dma_addr_t dma_addr, + size_t size, + enum dma_data_direction direction, + struct dma_attrs *attrs) +{ +} + +static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + struct scatterlist *sg; + int i; + + for_each_sg(sgl, sg, nents, i) { + sg->dma_address = sg_phys(sg) + get_dma_direct_offset(dev); + sg->dma_length = sg->length; + } + + return nents; +} + +static void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sg, + int nents, enum dma_data_direction direction, + struct dma_attrs *attrs) +{ +} + +static int dma_direct_dma_supported(struct device *dev, u64 mask) +{ + /* Could be improved to check for memory though it better be + * done via some global so platforms can set the limit in case + * they have limited DMA windows + */ + return mask >= DMA_32BIT_MASK; +} + +struct dma_mapping_ops dma_direct_ops = { + .alloc_coherent = dma_direct_alloc_coherent, + .free_coherent = dma_direct_free_coherent, + .map_single = dma_direct_map_single, + .unmap_single = dma_direct_unmap_single, + .map_sg = dma_direct_map_sg, + .unmap_sg = dma_direct_unmap_sg, + .dma_supported = dma_direct_dma_supported, +}; +EXPORT_SYMBOL(dma_direct_ops); |