diff options
Diffstat (limited to 'arch/tile/kernel/pci-dma.c')
| -rw-r--r-- | arch/tile/kernel/pci-dma.c | 593 |
1 files changed, 486 insertions, 107 deletions
diff --git a/arch/tile/kernel/pci-dma.c b/arch/tile/kernel/pci-dma.c index 5ad5e13b0fa..09b58703ac2 100644 --- a/arch/tile/kernel/pci-dma.c +++ b/arch/tile/kernel/pci-dma.c @@ -14,23 +14,31 @@ #include <linux/mm.h> #include <linux/dma-mapping.h> +#include <linux/swiotlb.h> #include <linux/vmalloc.h> +#include <linux/export.h> #include <asm/tlbflush.h> #include <asm/homecache.h> /* Generic DMA mapping functions: */ /* - * Allocate what Linux calls "coherent" memory, which for us just - * means uncached. + * Allocate what Linux calls "coherent" memory. On TILEPro this is + * uncached memory; on TILE-Gx it is hash-for-home memory. */ -void *dma_alloc_coherent(struct device *dev, - size_t size, - dma_addr_t *dma_handle, - gfp_t gfp) +#ifdef __tilepro__ +#define PAGE_HOME_DMA PAGE_HOME_UNCACHED +#else +#define PAGE_HOME_DMA PAGE_HOME_HASH +#endif + +static void *tile_dma_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, + struct dma_attrs *attrs) { - u64 dma_mask = dev->coherent_dma_mask ?: DMA_BIT_MASK(32); - int node = dev_to_node(dev); + u64 dma_mask = (dev && dev->coherent_dma_mask) ? + dev->coherent_dma_mask : DMA_BIT_MASK(32); + int node = dev ? dev_to_node(dev) : 0; int order = get_order(size); struct page *pg; dma_addr_t addr; @@ -38,39 +46,42 @@ void *dma_alloc_coherent(struct device *dev, gfp |= __GFP_ZERO; /* - * By forcing NUMA node 0 for 32-bit masks we ensure that the - * high 32 bits of the resulting PA will be zero. If the mask - * size is, e.g., 24, we may still not be able to guarantee a - * suitable memory address, in which case we will return NULL. - * But such devices are uncommon. + * If the mask specifies that the memory be in the first 4 GB, then + * we force the allocation to come from the DMA zone. We also + * force the node to 0 since that's the only node where the DMA + * zone isn't empty. If the mask size is smaller than 32 bits, we + * may still not be able to guarantee a suitable memory address, in + * which case we will return NULL. But such devices are uncommon. */ - if (dma_mask <= DMA_BIT_MASK(32)) + if (dma_mask <= DMA_BIT_MASK(32)) { + gfp |= GFP_DMA; node = 0; + } - pg = homecache_alloc_pages_node(node, gfp, order, PAGE_HOME_UNCACHED); + pg = homecache_alloc_pages_node(node, gfp, order, PAGE_HOME_DMA); if (pg == NULL) return NULL; addr = page_to_phys(pg); if (addr + size > dma_mask) { - homecache_free_pages(addr, order); + __homecache_free_pages(pg, order); return NULL; } *dma_handle = addr; + return page_address(pg); } -EXPORT_SYMBOL(dma_alloc_coherent); /* - * Free memory that was allocated with dma_alloc_coherent. + * Free memory that was allocated with tile_dma_alloc_coherent. */ -void dma_free_coherent(struct device *dev, size_t size, - void *vaddr, dma_addr_t dma_handle) +static void tile_dma_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_handle, + struct dma_attrs *attrs) { homecache_free_pages((unsigned long)vaddr, get_order(size)); } -EXPORT_SYMBOL(dma_free_coherent); /* * The map routines "map" the specified address range for DMA @@ -86,51 +97,112 @@ EXPORT_SYMBOL(dma_free_coherent); * can count on nothing having been touched. */ - -/* - * dma_map_single can be passed any memory address, and there appear - * to be no alignment constraints. - * - * There is a chance that the start of the buffer will share a cache - * line with some other data that has been touched in the meantime. - */ -dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size, - enum dma_data_direction direction) +/* Set up a single page for DMA access. */ +static void __dma_prep_page(struct page *page, unsigned long offset, + size_t size, enum dma_data_direction direction) { - struct page *page; - dma_addr_t dma_addr; - int thispage; + /* + * Flush the page from cache if necessary. + * On tilegx, data is delivered to hash-for-home L3; on tilepro, + * data is delivered direct to memory. + * + * NOTE: If we were just doing DMA_TO_DEVICE we could optimize + * this to be a "flush" not a "finv" and keep some of the + * state in cache across the DMA operation, but it doesn't seem + * worth creating the necessary flush_buffer_xxx() infrastructure. + */ + int home = page_home(page); + switch (home) { + case PAGE_HOME_HASH: +#ifdef __tilegx__ + return; +#endif + break; + case PAGE_HOME_UNCACHED: +#ifdef __tilepro__ + return; +#endif + break; + case PAGE_HOME_IMMUTABLE: + /* Should be going to the device only. */ + BUG_ON(direction == DMA_FROM_DEVICE || + direction == DMA_BIDIRECTIONAL); + return; + case PAGE_HOME_INCOHERENT: + /* Incoherent anyway, so no need to work hard here. */ + return; + default: + BUG_ON(home < 0 || home >= NR_CPUS); + break; + } + homecache_finv_page(page); + +#ifdef DEBUG_ALIGNMENT + /* Warn if the region isn't cacheline aligned. */ + if (offset & (L2_CACHE_BYTES - 1) || (size & (L2_CACHE_BYTES - 1))) + pr_warn("Unaligned DMA to non-hfh memory: PA %#llx/%#lx\n", + PFN_PHYS(page_to_pfn(page)) + offset, size); +#endif +} - BUG_ON(!valid_dma_direction(direction)); - WARN_ON(size == 0); - - dma_addr = __pa(ptr); - - /* We might have been handed a buffer that wraps a page boundary */ - while ((int)size > 0) { - /* The amount to flush that's on this page */ - thispage = PAGE_SIZE - ((unsigned long)ptr & (PAGE_SIZE - 1)); - thispage = min((int)thispage, (int)size); - /* Is this valid for any page we could be handed? */ - page = pfn_to_page(kaddr_to_pfn(ptr)); - homecache_flush_cache(page, 0); - ptr += thispage; - size -= thispage; +/* Make the page ready to be read by the core. */ +static void __dma_complete_page(struct page *page, unsigned long offset, + size_t size, enum dma_data_direction direction) +{ +#ifdef __tilegx__ + switch (page_home(page)) { + case PAGE_HOME_HASH: + /* I/O device delivered data the way the cpu wanted it. */ + break; + case PAGE_HOME_INCOHERENT: + /* Incoherent anyway, so no need to work hard here. */ + break; + case PAGE_HOME_IMMUTABLE: + /* Extra read-only copies are not a problem. */ + break; + default: + /* Flush the bogus hash-for-home I/O entries to memory. */ + homecache_finv_map_page(page, PAGE_HOME_HASH); + break; } +#endif +} - return dma_addr; +static void __dma_prep_pa_range(dma_addr_t dma_addr, size_t size, + enum dma_data_direction direction) +{ + struct page *page = pfn_to_page(PFN_DOWN(dma_addr)); + unsigned long offset = dma_addr & (PAGE_SIZE - 1); + size_t bytes = min(size, (size_t)(PAGE_SIZE - offset)); + + while (size != 0) { + __dma_prep_page(page, offset, bytes, direction); + size -= bytes; + ++page; + offset = 0; + bytes = min((size_t)PAGE_SIZE, size); + } } -EXPORT_SYMBOL(dma_map_single); -void dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size, - enum dma_data_direction direction) +static void __dma_complete_pa_range(dma_addr_t dma_addr, size_t size, + enum dma_data_direction direction) { - BUG_ON(!valid_dma_direction(direction)); + struct page *page = pfn_to_page(PFN_DOWN(dma_addr)); + unsigned long offset = dma_addr & (PAGE_SIZE - 1); + size_t bytes = min(size, (size_t)(PAGE_SIZE - offset)); + + while (size != 0) { + __dma_complete_page(page, offset, bytes, direction); + size -= bytes; + ++page; + offset = 0; + bytes = min((size_t)PAGE_SIZE, size); + } } -EXPORT_SYMBOL(dma_unmap_single); -int dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents, - enum dma_data_direction direction) +static int tile_dma_map_sg(struct device *dev, struct scatterlist *sglist, + int nents, enum dma_data_direction direction, + struct dma_attrs *attrs) { struct scatterlist *sg; int i; @@ -140,75 +212,277 @@ int dma_map_sg(struct device *dev, struct scatterlist *sglist, int nents, WARN_ON(nents == 0 || sglist->length == 0); for_each_sg(sglist, sg, nents, i) { - struct page *page; sg->dma_address = sg_phys(sg); - page = pfn_to_page(sg->dma_address >> PAGE_SHIFT); - homecache_flush_cache(page, 0); + __dma_prep_pa_range(sg->dma_address, sg->length, direction); +#ifdef CONFIG_NEED_SG_DMA_LENGTH + sg->dma_length = sg->length; +#endif } return nents; } -EXPORT_SYMBOL(dma_map_sg); -void dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nhwentries, - enum dma_data_direction direction) +static void tile_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, + int nents, enum dma_data_direction direction, + struct dma_attrs *attrs) { + struct scatterlist *sg; + int i; + BUG_ON(!valid_dma_direction(direction)); + for_each_sg(sglist, sg, nents, i) { + sg->dma_address = sg_phys(sg); + __dma_complete_pa_range(sg->dma_address, sg->length, + direction); + } } -EXPORT_SYMBOL(dma_unmap_sg); -dma_addr_t dma_map_page(struct device *dev, struct page *page, - unsigned long offset, size_t size, - enum dma_data_direction direction) +static dma_addr_t tile_dma_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction direction, + struct dma_attrs *attrs) { BUG_ON(!valid_dma_direction(direction)); - homecache_flush_cache(page, 0); + BUG_ON(offset + size > PAGE_SIZE); + __dma_prep_page(page, offset, size, direction); return page_to_pa(page) + offset; } -EXPORT_SYMBOL(dma_map_page); -void dma_unmap_page(struct device *dev, dma_addr_t dma_address, size_t size, - enum dma_data_direction direction) +static void tile_dma_unmap_page(struct device *dev, dma_addr_t dma_address, + size_t size, enum dma_data_direction direction, + struct dma_attrs *attrs) { BUG_ON(!valid_dma_direction(direction)); + + __dma_complete_page(pfn_to_page(PFN_DOWN(dma_address)), + dma_address & (PAGE_SIZE - 1), size, direction); } -EXPORT_SYMBOL(dma_unmap_page); -void dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, - size_t size, enum dma_data_direction direction) +static void tile_dma_sync_single_for_cpu(struct device *dev, + dma_addr_t dma_handle, + size_t size, + enum dma_data_direction direction) { BUG_ON(!valid_dma_direction(direction)); + + __dma_complete_pa_range(dma_handle, size, direction); } -EXPORT_SYMBOL(dma_sync_single_for_cpu); -void dma_sync_single_for_device(struct device *dev, dma_addr_t dma_handle, - size_t size, enum dma_data_direction direction) +static void tile_dma_sync_single_for_device(struct device *dev, + dma_addr_t dma_handle, size_t size, + enum dma_data_direction direction) { - unsigned long start = PFN_DOWN(dma_handle); - unsigned long end = PFN_DOWN(dma_handle + size - 1); - unsigned long i; + __dma_prep_pa_range(dma_handle, size, direction); +} + +static void tile_dma_sync_sg_for_cpu(struct device *dev, + struct scatterlist *sglist, int nelems, + enum dma_data_direction direction) +{ + struct scatterlist *sg; + int i; BUG_ON(!valid_dma_direction(direction)); - for (i = start; i <= end; ++i) - homecache_flush_cache(pfn_to_page(i), 0); + WARN_ON(nelems == 0 || sglist->length == 0); + + for_each_sg(sglist, sg, nelems, i) { + dma_sync_single_for_cpu(dev, sg->dma_address, + sg_dma_len(sg), direction); + } } -EXPORT_SYMBOL(dma_sync_single_for_device); -void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, int nelems, - enum dma_data_direction direction) +static void tile_dma_sync_sg_for_device(struct device *dev, + struct scatterlist *sglist, int nelems, + enum dma_data_direction direction) { + struct scatterlist *sg; + int i; + BUG_ON(!valid_dma_direction(direction)); - WARN_ON(nelems == 0 || sg[0].length == 0); + WARN_ON(nelems == 0 || sglist->length == 0); + + for_each_sg(sglist, sg, nelems, i) { + dma_sync_single_for_device(dev, sg->dma_address, + sg_dma_len(sg), direction); + } +} + +static inline int +tile_dma_mapping_error(struct device *dev, dma_addr_t dma_addr) +{ + return 0; +} + +static inline int +tile_dma_supported(struct device *dev, u64 mask) +{ + return 1; +} + +static struct dma_map_ops tile_default_dma_map_ops = { + .alloc = tile_dma_alloc_coherent, + .free = tile_dma_free_coherent, + .map_page = tile_dma_map_page, + .unmap_page = tile_dma_unmap_page, + .map_sg = tile_dma_map_sg, + .unmap_sg = tile_dma_unmap_sg, + .sync_single_for_cpu = tile_dma_sync_single_for_cpu, + .sync_single_for_device = tile_dma_sync_single_for_device, + .sync_sg_for_cpu = tile_dma_sync_sg_for_cpu, + .sync_sg_for_device = tile_dma_sync_sg_for_device, + .mapping_error = tile_dma_mapping_error, + .dma_supported = tile_dma_supported +}; + +struct dma_map_ops *tile_dma_map_ops = &tile_default_dma_map_ops; +EXPORT_SYMBOL(tile_dma_map_ops); + +/* Generic PCI DMA mapping functions */ + +static void *tile_pci_dma_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, + struct dma_attrs *attrs) +{ + int node = dev_to_node(dev); + int order = get_order(size); + struct page *pg; + dma_addr_t addr; + + gfp |= __GFP_ZERO; + + pg = homecache_alloc_pages_node(node, gfp, order, PAGE_HOME_DMA); + if (pg == NULL) + return NULL; + + addr = page_to_phys(pg); + + *dma_handle = addr + get_dma_offset(dev); + + return page_address(pg); } -EXPORT_SYMBOL(dma_sync_sg_for_cpu); /* - * Flush and invalidate cache for scatterlist. + * Free memory that was allocated with tile_pci_dma_alloc_coherent. */ -void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist, - int nelems, enum dma_data_direction direction) +static void tile_pci_dma_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_handle, + struct dma_attrs *attrs) +{ + homecache_free_pages((unsigned long)vaddr, get_order(size)); +} + +static int tile_pci_dma_map_sg(struct device *dev, struct scatterlist *sglist, + int nents, enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + struct scatterlist *sg; + int i; + + BUG_ON(!valid_dma_direction(direction)); + + WARN_ON(nents == 0 || sglist->length == 0); + + for_each_sg(sglist, sg, nents, i) { + sg->dma_address = sg_phys(sg); + __dma_prep_pa_range(sg->dma_address, sg->length, direction); + + sg->dma_address = sg->dma_address + get_dma_offset(dev); +#ifdef CONFIG_NEED_SG_DMA_LENGTH + sg->dma_length = sg->length; +#endif + } + + return nents; +} + +static void tile_pci_dma_unmap_sg(struct device *dev, + struct scatterlist *sglist, int nents, + enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + struct scatterlist *sg; + int i; + + BUG_ON(!valid_dma_direction(direction)); + for_each_sg(sglist, sg, nents, i) { + sg->dma_address = sg_phys(sg); + __dma_complete_pa_range(sg->dma_address, sg->length, + direction); + } +} + +static dma_addr_t tile_pci_dma_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + BUG_ON(!valid_dma_direction(direction)); + + BUG_ON(offset + size > PAGE_SIZE); + __dma_prep_page(page, offset, size, direction); + + return page_to_pa(page) + offset + get_dma_offset(dev); +} + +static void tile_pci_dma_unmap_page(struct device *dev, dma_addr_t dma_address, + size_t size, + enum dma_data_direction direction, + struct dma_attrs *attrs) +{ + BUG_ON(!valid_dma_direction(direction)); + + dma_address -= get_dma_offset(dev); + + __dma_complete_page(pfn_to_page(PFN_DOWN(dma_address)), + dma_address & (PAGE_SIZE - 1), size, direction); +} + +static void tile_pci_dma_sync_single_for_cpu(struct device *dev, + dma_addr_t dma_handle, + size_t size, + enum dma_data_direction direction) +{ + BUG_ON(!valid_dma_direction(direction)); + + dma_handle -= get_dma_offset(dev); + + __dma_complete_pa_range(dma_handle, size, direction); +} + +static void tile_pci_dma_sync_single_for_device(struct device *dev, + dma_addr_t dma_handle, + size_t size, + enum dma_data_direction + direction) +{ + dma_handle -= get_dma_offset(dev); + + __dma_prep_pa_range(dma_handle, size, direction); +} + +static void tile_pci_dma_sync_sg_for_cpu(struct device *dev, + struct scatterlist *sglist, + int nelems, + enum dma_data_direction direction) +{ + struct scatterlist *sg; + int i; + + BUG_ON(!valid_dma_direction(direction)); + WARN_ON(nelems == 0 || sglist->length == 0); + + for_each_sg(sglist, sg, nelems, i) { + dma_sync_single_for_cpu(dev, sg->dma_address, + sg_dma_len(sg), direction); + } +} + +static void tile_pci_dma_sync_sg_for_device(struct device *dev, + struct scatterlist *sglist, + int nelems, + enum dma_data_direction direction) { struct scatterlist *sg; int i; @@ -221,31 +495,136 @@ void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sglist, sg_dma_len(sg), direction); } } -EXPORT_SYMBOL(dma_sync_sg_for_device); -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 int +tile_pci_dma_mapping_error(struct device *dev, dma_addr_t dma_addr) +{ + return 0; +} + +static inline int +tile_pci_dma_supported(struct device *dev, u64 mask) +{ + return 1; +} + +static struct dma_map_ops tile_pci_default_dma_map_ops = { + .alloc = tile_pci_dma_alloc_coherent, + .free = tile_pci_dma_free_coherent, + .map_page = tile_pci_dma_map_page, + .unmap_page = tile_pci_dma_unmap_page, + .map_sg = tile_pci_dma_map_sg, + .unmap_sg = tile_pci_dma_unmap_sg, + .sync_single_for_cpu = tile_pci_dma_sync_single_for_cpu, + .sync_single_for_device = tile_pci_dma_sync_single_for_device, + .sync_sg_for_cpu = tile_pci_dma_sync_sg_for_cpu, + .sync_sg_for_device = tile_pci_dma_sync_sg_for_device, + .mapping_error = tile_pci_dma_mapping_error, + .dma_supported = tile_pci_dma_supported +}; + +struct dma_map_ops *gx_pci_dma_map_ops = &tile_pci_default_dma_map_ops; +EXPORT_SYMBOL(gx_pci_dma_map_ops); + +/* PCI DMA mapping functions for legacy PCI devices */ + +#ifdef CONFIG_SWIOTLB +static void *tile_swiotlb_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, + struct dma_attrs *attrs) { - dma_sync_single_for_cpu(dev, dma_handle + offset, size, direction); + gfp |= GFP_DMA; + return swiotlb_alloc_coherent(dev, size, dma_handle, gfp); } -EXPORT_SYMBOL(dma_sync_single_range_for_cpu); -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) +static void tile_swiotlb_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t dma_addr, + struct dma_attrs *attrs) { - dma_sync_single_for_device(dev, dma_handle + offset, size, direction); + swiotlb_free_coherent(dev, size, vaddr, dma_addr); +} + +static struct dma_map_ops pci_swiotlb_dma_ops = { + .alloc = tile_swiotlb_alloc_coherent, + .free = tile_swiotlb_free_coherent, + .map_page = swiotlb_map_page, + .unmap_page = swiotlb_unmap_page, + .map_sg = swiotlb_map_sg_attrs, + .unmap_sg = swiotlb_unmap_sg_attrs, + .sync_single_for_cpu = swiotlb_sync_single_for_cpu, + .sync_single_for_device = swiotlb_sync_single_for_device, + .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu, + .sync_sg_for_device = swiotlb_sync_sg_for_device, + .dma_supported = swiotlb_dma_supported, + .mapping_error = swiotlb_dma_mapping_error, +}; + +static struct dma_map_ops pci_hybrid_dma_ops = { + .alloc = tile_swiotlb_alloc_coherent, + .free = tile_swiotlb_free_coherent, + .map_page = tile_pci_dma_map_page, + .unmap_page = tile_pci_dma_unmap_page, + .map_sg = tile_pci_dma_map_sg, + .unmap_sg = tile_pci_dma_unmap_sg, + .sync_single_for_cpu = tile_pci_dma_sync_single_for_cpu, + .sync_single_for_device = tile_pci_dma_sync_single_for_device, + .sync_sg_for_cpu = tile_pci_dma_sync_sg_for_cpu, + .sync_sg_for_device = tile_pci_dma_sync_sg_for_device, + .mapping_error = tile_pci_dma_mapping_error, + .dma_supported = tile_pci_dma_supported +}; + +struct dma_map_ops *gx_legacy_pci_dma_map_ops = &pci_swiotlb_dma_ops; +struct dma_map_ops *gx_hybrid_pci_dma_map_ops = &pci_hybrid_dma_ops; +#else +struct dma_map_ops *gx_legacy_pci_dma_map_ops; +struct dma_map_ops *gx_hybrid_pci_dma_map_ops; +#endif +EXPORT_SYMBOL(gx_legacy_pci_dma_map_ops); +EXPORT_SYMBOL(gx_hybrid_pci_dma_map_ops); + +#ifdef CONFIG_ARCH_HAS_DMA_SET_COHERENT_MASK +int dma_set_coherent_mask(struct device *dev, u64 mask) +{ + struct dma_map_ops *dma_ops = get_dma_ops(dev); + + /* + * For PCI devices with 64-bit DMA addressing capability, promote + * the dma_ops to full capability for both streams and consistent + * memory access. For 32-bit capable devices, limit the consistent + * memory DMA range to max_direct_dma_addr. + */ + if (dma_ops == gx_pci_dma_map_ops || + dma_ops == gx_hybrid_pci_dma_map_ops || + dma_ops == gx_legacy_pci_dma_map_ops) { + if (mask == DMA_BIT_MASK(64)) + set_dma_ops(dev, gx_pci_dma_map_ops); + else if (mask > dev->archdata.max_direct_dma_addr) + mask = dev->archdata.max_direct_dma_addr; + } + + if (!dma_supported(dev, mask)) + return -EIO; + dev->coherent_dma_mask = mask; + return 0; } -EXPORT_SYMBOL(dma_sync_single_range_for_device); +EXPORT_SYMBOL(dma_set_coherent_mask); +#endif +#ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK /* - * dma_alloc_noncoherent() returns non-cacheable memory, so there's no - * need to do any flushing here. + * The generic dma_get_required_mask() uses the highest physical address + * (max_pfn) to provide the hint to the PCI drivers regarding 32-bit or + * 64-bit DMA configuration. Since TILEGx has I/O TLB/MMU, allowing the + * DMAs to use the full 64-bit PCI address space and not limited by + * the physical memory space, we always let the PCI devices use + * 64-bit DMA if they have that capability, by returning the 64-bit + * DMA mask here. The device driver has the option to use 32-bit DMA if + * the device is not capable of 64-bit DMA. */ -void dma_cache_sync(void *vaddr, size_t size, - enum dma_data_direction direction) +u64 dma_get_required_mask(struct device *dev) { + return DMA_BIT_MASK(64); } -EXPORT_SYMBOL(dma_cache_sync); +EXPORT_SYMBOL_GPL(dma_get_required_mask); +#endif |
