diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/sysdev/dart_iommu.c | 74 |
1 files changed, 64 insertions, 10 deletions
diff --git a/arch/powerpc/sysdev/dart_iommu.c b/arch/powerpc/sysdev/dart_iommu.c index 559db2b846a9..17cf15ec38be 100644 --- a/arch/powerpc/sysdev/dart_iommu.c +++ b/arch/powerpc/sysdev/dart_iommu.c @@ -70,6 +70,8 @@ static int iommu_table_dart_inited; static int dart_dirty; static int dart_is_u4; +#define DART_U4_BYPASS_BASE 0x8000000000ull + #define DBG(...) static inline void dart_tlb_invalidate_all(void) @@ -292,12 +294,20 @@ static void iommu_table_dart_setup(void) set_bit(iommu_table_dart.it_size - 1, iommu_table_dart.it_map); } -static void pci_dma_dev_setup_dart(struct pci_dev *dev) +static void dma_dev_setup_dart(struct device *dev) { /* We only have one iommu table on the mac for now, which makes * things simple. Setup all PCI devices to point to this table */ - set_iommu_table_base(&dev->dev, &iommu_table_dart); + if (get_dma_ops(dev) == &dma_direct_ops) + set_dma_offset(dev, DART_U4_BYPASS_BASE); + else + set_iommu_table_base(dev, &iommu_table_dart); +} + +static void pci_dma_dev_setup_dart(struct pci_dev *dev) +{ + dma_dev_setup_dart(&dev->dev); } static void pci_dma_bus_setup_dart(struct pci_bus *bus) @@ -315,6 +325,45 @@ static void pci_dma_bus_setup_dart(struct pci_bus *bus) PCI_DN(dn)->iommu_table = &iommu_table_dart; } +static bool dart_device_on_pcie(struct device *dev) +{ + struct device_node *np = of_node_get(dev->of_node); + + while(np) { + if (of_device_is_compatible(np, "U4-pcie") || + of_device_is_compatible(np, "u4-pcie")) { + of_node_put(np); + return true; + } + np = of_get_next_parent(np); + } + return false; +} + +static int dart_dma_set_mask(struct device *dev, u64 dma_mask) +{ + if (!dev->dma_mask || !dma_supported(dev, dma_mask)) + return -EIO; + + /* U4 supports a DART bypass, we use it for 64-bit capable + * devices to improve performances. However, that only works + * for devices connected to U4 own PCIe interface, not bridged + * through hypertransport. We need the device to support at + * least 40 bits of addresses. + */ + if (dart_device_on_pcie(dev) && dma_mask >= DMA_BIT_MASK(40)) { + dev_info(dev, "Using 64-bit DMA iommu bypass\n"); + set_dma_ops(dev, &dma_direct_ops); + } else { + dev_info(dev, "Using 32-bit DMA via iommu\n"); + set_dma_ops(dev, &dma_iommu_ops); + } + dma_dev_setup_dart(dev); + + *dev->dma_mask = dma_mask; + return 0; +} + void __init iommu_init_early_dart(void) { struct device_node *dn; @@ -328,20 +377,25 @@ void __init iommu_init_early_dart(void) dart_is_u4 = 1; } + /* Initialize the DART HW */ + if (dart_init(dn) != 0) + goto bail; + /* Setup low level TCE operations for the core IOMMU code */ ppc_md.tce_build = dart_build; ppc_md.tce_free = dart_free; ppc_md.tce_flush = dart_flush; - /* Initialize the DART HW */ - if (dart_init(dn) == 0) { - ppc_md.pci_dma_dev_setup = pci_dma_dev_setup_dart; - ppc_md.pci_dma_bus_setup = pci_dma_bus_setup_dart; + /* Setup bypass if supported */ + if (dart_is_u4) + ppc_md.dma_set_mask = dart_dma_set_mask; - /* Setup pci_dma ops */ - set_pci_dma_ops(&dma_iommu_ops); - return; - } + ppc_md.pci_dma_dev_setup = pci_dma_dev_setup_dart; + ppc_md.pci_dma_bus_setup = pci_dma_bus_setup_dart; + + /* Setup pci_dma ops */ + set_pci_dma_ops(&dma_iommu_ops); + return; bail: /* If init failed, use direct iommu and null setup functions */ |