diff options
Diffstat (limited to 'arch/powerpc/kernel/dma-iommu.c')
| -rw-r--r-- | arch/powerpc/kernel/dma-iommu.c | 75 |
1 files changed, 66 insertions, 9 deletions
diff --git a/arch/powerpc/kernel/dma-iommu.c b/arch/powerpc/kernel/dma-iommu.c index 9c9bcaae2f75..09231ef06d01 100644 --- a/arch/powerpc/kernel/dma-iommu.c +++ b/arch/powerpc/kernel/dma-iommu.c @@ -6,12 +6,31 @@ * busses using the iommu infrastructure */ +#include <linux/dma-direct.h> +#include <linux/pci.h> #include <asm/iommu.h> /* * Generic iommu implementation */ +/* + * The coherent mask may be smaller than the real mask, check if we can + * really use a direct window. + */ +static inline bool dma_iommu_alloc_bypass(struct device *dev) +{ + return dev->archdata.iommu_bypass && !iommu_fixed_is_weak && + dma_direct_supported(dev, dev->coherent_dma_mask); +} + +static inline bool dma_iommu_map_bypass(struct device *dev, + unsigned long attrs) +{ + return dev->archdata.iommu_bypass && + (!iommu_fixed_is_weak || (attrs & DMA_ATTR_WEAK_ORDERING)); +} + /* 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. @@ -20,6 +39,8 @@ static void *dma_iommu_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs) { + if (dma_iommu_alloc_bypass(dev)) + return dma_direct_alloc(dev, size, dma_handle, flag, attrs); return iommu_alloc_coherent(dev, get_iommu_table_base(dev), size, dma_handle, dev->coherent_dma_mask, flag, dev_to_node(dev)); @@ -29,7 +50,11 @@ static void dma_iommu_free_coherent(struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle, unsigned long attrs) { - iommu_free_coherent(get_iommu_table_base(dev), size, vaddr, dma_handle); + if (dma_iommu_alloc_bypass(dev)) + dma_direct_free(dev, size, vaddr, dma_handle, attrs); + else + iommu_free_coherent(get_iommu_table_base(dev), size, vaddr, + dma_handle); } /* Creates TCEs for a user provided buffer. The user buffer must be @@ -42,6 +67,9 @@ static dma_addr_t dma_iommu_map_page(struct device *dev, struct page *page, enum dma_data_direction direction, unsigned long attrs) { + if (dma_iommu_map_bypass(dev, attrs)) + return dma_direct_map_page(dev, page, offset, size, direction, + attrs); return iommu_map_page(dev, get_iommu_table_base(dev), page, offset, size, device_to_mask(dev), direction, attrs); } @@ -51,8 +79,9 @@ static void dma_iommu_unmap_page(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction direction, unsigned long attrs) { - iommu_unmap_page(get_iommu_table_base(dev), dma_handle, size, direction, - attrs); + if (!dma_iommu_map_bypass(dev, attrs)) + iommu_unmap_page(get_iommu_table_base(dev), dma_handle, size, + direction, attrs); } @@ -60,6 +89,8 @@ static int dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist, int nelems, enum dma_data_direction direction, unsigned long attrs) { + if (dma_iommu_map_bypass(dev, attrs)) + return dma_direct_map_sg(dev, sglist, nelems, direction, attrs); return ppc_iommu_map_sg(dev, get_iommu_table_base(dev), sglist, nelems, device_to_mask(dev), direction, attrs); } @@ -68,10 +99,20 @@ static void dma_iommu_unmap_sg(struct device *dev, struct scatterlist *sglist, int nelems, enum dma_data_direction direction, unsigned long attrs) { - ppc_iommu_unmap_sg(get_iommu_table_base(dev), sglist, nelems, + if (!dma_iommu_map_bypass(dev, attrs)) + ppc_iommu_unmap_sg(get_iommu_table_base(dev), sglist, nelems, direction, attrs); } +static bool dma_iommu_bypass_supported(struct device *dev, u64 mask) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct pci_controller *phb = pci_bus_to_host(pdev->bus); + + return phb->controller_ops.iommu_bypass_supported && + phb->controller_ops.iommu_bypass_supported(pdev, mask); +} + /* We support DMA to/from any memory page via the iommu */ int dma_iommu_dma_supported(struct device *dev, u64 mask) { @@ -83,32 +124,48 @@ int dma_iommu_dma_supported(struct device *dev, u64 mask) return 0; } + if (dev_is_pci(dev) && dma_iommu_bypass_supported(dev, mask)) { + dev->archdata.iommu_bypass = true; + dev_dbg(dev, "iommu: 64-bit OK, using fixed ops\n"); + return 1; + } + if (tbl->it_offset > (mask >> tbl->it_page_shift)) { dev_info(dev, "Warning: IOMMU offset too big for device mask\n"); dev_info(dev, "mask: 0x%08llx, table offset: 0x%08lx\n", mask, tbl->it_offset << tbl->it_page_shift); return 0; - } else - return 1; + } + + dev_dbg(dev, "iommu: not 64-bit, using default ops\n"); + dev->archdata.iommu_bypass = false; + return 1; } -static u64 dma_iommu_get_required_mask(struct device *dev) +u64 dma_iommu_get_required_mask(struct device *dev) { struct iommu_table *tbl = get_iommu_table_base(dev); u64 mask; + if (!tbl) return 0; + if (dev_is_pci(dev)) { + u64 bypass_mask = dma_direct_get_required_mask(dev); + + if (dma_iommu_bypass_supported(dev, bypass_mask)) + return bypass_mask; + } + mask = 1ULL < (fls_long(tbl->it_offset + tbl->it_size) - 1); mask += mask - 1; return mask; } -struct dma_map_ops dma_iommu_ops = { +const struct dma_map_ops dma_iommu_ops = { .alloc = dma_iommu_alloc_coherent, .free = dma_iommu_free_coherent, - .mmap = dma_nommu_mmap_coherent, .map_sg = dma_iommu_map_sg, .unmap_sg = dma_iommu_unmap_sg, .dma_supported = dma_iommu_dma_supported, |