diff --git a/arch/ppc64/kernel/pSeries_iommu.c b/arch/ppc64/kernel/pSeries_iommu.c index f0fd7fbd6531..8c6313e7e145 100644 --- a/arch/ppc64/kernel/pSeries_iommu.c +++ b/arch/ppc64/kernel/pSeries_iommu.c @@ -265,8 +265,10 @@ static void iommu_table_setparms(struct pci_controller *phb, tbl->it_offset = phb->dma_window_base_cur >> PAGE_SHIFT; /* Test if we are going over 2GB of DMA space */ - if (phb->dma_window_base_cur + phb->dma_window_size > (1L << 31)) + if (phb->dma_window_base_cur + phb->dma_window_size > 0x80000000ul) { + udbg_printf("PCI_DMA: Unexpected number of IOAs under this PHB.\n"); panic("PCI_DMA: Unexpected number of IOAs under this PHB.\n"); + } phb->dma_window_base_cur += phb->dma_window_size; @@ -310,92 +312,84 @@ static void iommu_table_setparms_lpar(struct pci_controller *phb, static void iommu_bus_setup_pSeries(struct pci_bus *bus) { - struct device_node *dn, *pdn; - struct pci_dn *pci; + struct device_node *dn; struct iommu_table *tbl; + struct device_node *isa_dn, *isa_dn_orig; + struct device_node *tmp; + struct pci_dn *pci; + int children; DBG("iommu_bus_setup_pSeries, bus %p, bus->self %p\n", bus, bus->self); - /* For each (root) bus, we carve up the available DMA space in 256MB - * pieces. Since each piece is used by one (sub) bus/device, that would - * give a maximum of 7 devices per PHB. In most cases, this is plenty. + dn = pci_bus_to_OF_node(bus); + pci = PCI_DN(dn); + + if (bus->self) { + /* This is not a root bus, any setup will be done for the + * device-side of the bridge in iommu_dev_setup_pSeries(). + */ + return; + } + + /* Check if the ISA bus on the system is under + * this PHB. + */ + isa_dn = isa_dn_orig = of_find_node_by_type(NULL, "isa"); + + while (isa_dn && isa_dn != dn) + isa_dn = isa_dn->parent; + + if (isa_dn_orig) + of_node_put(isa_dn_orig); + + /* Count number of direct PCI children of the PHB. + * All PCI device nodes have class-code property, so it's + * an easy way to find them. + */ + for (children = 0, tmp = dn->child; tmp; tmp = tmp->sibling) + if (get_property(tmp, "class-code", NULL)) + children++; + + DBG("Children: %d\n", children); + + /* Calculate amount of DMA window per slot. Each window must be + * a power of two (due to pci_alloc_consistent requirements). * - * The exception is on Python PHBs (pre-POWER4). Here we don't have EADS - * bridges below the PHB to allocate the sectioned tables to, so instead - * we allocate a 1GB table at the PHB level. + * Keep 256MB aside for PHBs with ISA. */ - dn = pci_bus_to_OF_node(bus); - pci = dn->data; + if (!isa_dn) { + /* No ISA/IDE - just set window size and return */ + pci->phb->dma_window_size = 0x80000000ul; /* To be divided */ - if (!bus->self) { - /* Root bus */ - if (is_python(dn)) { - unsigned int *iohole; + while (pci->phb->dma_window_size * children > 0x80000000ul) + pci->phb->dma_window_size >>= 1; + DBG("No ISA/IDE, window size is %x\n", pci->phb->dma_window_size); + pci->phb->dma_window_base_cur = 0; - DBG("Python root bus %s\n", bus->name); - - iohole = (unsigned int *)get_property(dn, "io-hole", 0); - - if (iohole) { - /* On first bus we need to leave room for the - * ISA address space. Just skip the first 256MB - * alltogether. This leaves 768MB for the window. - */ - DBG("PHB has io-hole, reserving 256MB\n"); - pci->phb->dma_window_size = 3 << 28; - pci->phb->dma_window_base_cur = 1 << 28; - } else { - /* 1GB window by default */ - pci->phb->dma_window_size = 1 << 30; - pci->phb->dma_window_base_cur = 0; - } - - tbl = kmalloc(sizeof(struct iommu_table), GFP_KERNEL); - - iommu_table_setparms(pci->phb, dn, tbl); - pci->iommu_table = iommu_init_table(tbl); - } else { - /* Do a 128MB table at root. This is used for the IDE - * controller on some SMP-mode POWER4 machines. It - * doesn't hurt to allocate it on other machines - * -- it'll just be unused since new tables are - * allocated on the EADS level. - * - * Allocate at offset 128MB to avoid having to deal - * with ISA holes; 128MB table for IDE is plenty. - */ - pci->phb->dma_window_size = 1 << 27; - pci->phb->dma_window_base_cur = 1 << 27; - - tbl = kmalloc(sizeof(struct iommu_table), GFP_KERNEL); - - iommu_table_setparms(pci->phb, dn, tbl); - pci->iommu_table = iommu_init_table(tbl); - - /* All child buses have 256MB tables */ - pci->phb->dma_window_size = 1 << 28; - } - } else { - pdn = pci_bus_to_OF_node(bus->parent); - - if (!bus->parent->self && !is_python(pdn)) { - struct iommu_table *tbl; - /* First child and not python means this is the EADS - * level. Allocate new table for this slot with 256MB - * window. - */ - - tbl = kmalloc(sizeof(struct iommu_table), GFP_KERNEL); - - iommu_table_setparms(pci->phb, dn, tbl); - - pci->iommu_table = iommu_init_table(tbl); - } else { - /* Lower than first child or under python, use parent table */ - pci->iommu_table = PCI_DN(pdn)->iommu_table; - } + return; } + + /* If we have ISA, then we probably have an IDE + * controller too. Allocate a 128MB table but + * skip the first 128MB to avoid stepping on ISA + * space. + */ + pci->phb->dma_window_size = 0x8000000ul; + pci->phb->dma_window_base_cur = 0x8000000ul; + + tbl = kmalloc(sizeof(struct iommu_table), GFP_KERNEL); + + iommu_table_setparms(pci->phb, dn, tbl); + pci->iommu_table = iommu_init_table(tbl); + + /* Divide the rest (1.75GB) among the children */ + pci->phb->dma_window_size = 0x80000000ul; + while (pci->phb->dma_window_size * children > 0x70000000ul) + pci->phb->dma_window_size >>= 1; + + DBG("ISA/IDE, window size is %x\n", pci->phb->dma_window_size); + } @@ -446,14 +440,29 @@ static void iommu_bus_setup_pSeriesLP(struct pci_bus *bus) static void iommu_dev_setup_pSeries(struct pci_dev *dev) { struct device_node *dn, *mydn; + struct iommu_table *tbl; DBG("iommu_dev_setup_pSeries, dev %p (%s)\n", dev, dev->pretty_name); - /* Now copy the iommu_table ptr from the bus device down to the - * pci device_node. This means get_iommu_table() won't need to search - * up the device tree to find it. - */ + mydn = dn = pci_device_to_OF_node(dev); + /* If we're the direct child of a root bus, then we need to allocate + * an iommu table ourselves. The bus setup code should have setup + * the window sizes already. + */ + if (!dev->bus->self) { + DBG(" --> first child, no bridge. Allocating iommu table.\n"); + tbl = kmalloc(sizeof(struct iommu_table), GFP_KERNEL); + iommu_table_setparms(PCI_DN(dn)->phb, dn, tbl); + PCI_DN(mydn)->iommu_table = iommu_init_table(tbl); + + return; + } + + /* If this device is further down the bus tree, search upwards until + * an already allocated iommu table is found and use that. + */ + while (dn && dn->data && PCI_DN(dn)->iommu_table == NULL) dn = dn->parent;