diff options
| -rw-r--r-- | arch/powerpc/include/asm/machdep.h | 3 | ||||
| -rw-r--r-- | arch/powerpc/kernel/pci-common.c | 20 | ||||
| -rw-r--r-- | arch/powerpc/platforms/powernv/pci-ioda.c | 39 | ||||
| -rw-r--r-- | drivers/pci/setup-bus.c | 81 | ||||
| -rw-r--r-- | include/linux/pci.h | 2 |
5 files changed, 124 insertions, 21 deletions
diff --git a/arch/powerpc/include/asm/machdep.h b/arch/powerpc/include/asm/machdep.h index 42ce570812c1..f7706d722b39 100644 --- a/arch/powerpc/include/asm/machdep.h +++ b/arch/powerpc/include/asm/machdep.h @@ -214,6 +214,9 @@ struct machdep_calls { /* Called after scan and before resource survey */ void (*pcibios_fixup_phb)(struct pci_controller *hose); + /* Called during PCI resource reassignment */ + resource_size_t (*pcibios_window_alignment)(struct pci_bus *, unsigned long type); + /* Called to shutdown machine specific hardware not already controlled * by other drivers. */ diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c index 2aa04f29e1de..43fea543d686 100644 --- a/arch/powerpc/kernel/pci-common.c +++ b/arch/powerpc/kernel/pci-common.c @@ -99,6 +99,26 @@ void pcibios_free_controller(struct pci_controller *phb) kfree(phb); } +/* + * The function is used to return the minimal alignment + * for memory or I/O windows of the associated P2P bridge. + * By default, 4KiB alignment for I/O windows and 1MiB for + * memory windows. + */ +resource_size_t pcibios_window_alignment(struct pci_bus *bus, + unsigned long type) +{ + if (ppc_md.pcibios_window_alignment) + return ppc_md.pcibios_window_alignment(bus, type); + + /* + * PCI core will figure out the default + * alignment: 4KiB for I/O and 1MiB for + * memory window. + */ + return 1; +} + static resource_size_t pcibios_io_size(const struct pci_controller *hose) { #ifdef CONFIG_PPC64 diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c index b46e1dadc882..0e7eccc0f88d 100644 --- a/arch/powerpc/platforms/powernv/pci-ioda.c +++ b/arch/powerpc/platforms/powernv/pci-ioda.c @@ -1139,6 +1139,44 @@ static void __devinit pnv_pci_ioda_fixup_phb(struct pci_controller *hose) } } +/* + * Returns the alignment for I/O or memory windows for P2P + * bridges. That actually depends on how PEs are segmented. + * For now, we return I/O or M32 segment size for PE sensitive + * P2P bridges. Otherwise, the default values (4KiB for I/O, + * 1MiB for memory) will be returned. + * + * The current PCI bus might be put into one PE, which was + * create against the parent PCI bridge. For that case, we + * needn't enlarge the alignment so that we can save some + * resources. + */ +static resource_size_t pnv_pci_window_alignment(struct pci_bus *bus, + unsigned long type) +{ + struct pci_dev *bridge; + struct pci_controller *hose = pci_bus_to_host(bus); + struct pnv_phb *phb = hose->private_data; + int num_pci_bridges = 0; + + bridge = bus->self; + while (bridge) { + if (pci_pcie_type(bridge) == PCI_EXP_TYPE_PCI_BRIDGE) { + num_pci_bridges++; + if (num_pci_bridges >= 2) + return 1; + } + + bridge = bridge->bus->self; + } + + /* We need support prefetchable memory window later */ + if (type & IORESOURCE_MEM) + return phb->ioda.m32_segsize; + + return phb->ioda.io_segsize; +} + /* Prevent enabling devices for which we couldn't properly * assign a PE */ @@ -1306,6 +1344,7 @@ void __init pnv_pci_init_ioda1_phb(struct device_node *np) */ ppc_md.pcibios_fixup_phb = pnv_pci_ioda_fixup_phb; ppc_md.pcibios_enable_device_hook = pnv_pci_enable_device_hook; + ppc_md.pcibios_window_alignment = pnv_pci_window_alignment; pci_add_flags(PCI_PROBE_ONLY | PCI_REASSIGN_ALL_RSRC); /* Reset IODA tables to a clean state */ diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index fb506137aaee..1e808ca338f8 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -697,6 +697,38 @@ static resource_size_t calculate_memsize(resource_size_t size, return size; } +resource_size_t __weak pcibios_window_alignment(struct pci_bus *bus, + unsigned long type) +{ + return 1; +} + +#define PCI_P2P_DEFAULT_MEM_ALIGN 0x100000 /* 1MiB */ +#define PCI_P2P_DEFAULT_IO_ALIGN 0x1000 /* 4KiB */ +#define PCI_P2P_DEFAULT_IO_ALIGN_1K 0x400 /* 1KiB */ + +static resource_size_t window_alignment(struct pci_bus *bus, + unsigned long type) +{ + resource_size_t align = 1, arch_align; + + if (type & IORESOURCE_MEM) + align = PCI_P2P_DEFAULT_MEM_ALIGN; + else if (type & IORESOURCE_IO) { + /* + * Per spec, I/O windows are 4K-aligned, but some + * bridges have an extension to support 1K alignment. + */ + if (bus->self->io_window_1k) + align = PCI_P2P_DEFAULT_IO_ALIGN_1K; + else + align = PCI_P2P_DEFAULT_IO_ALIGN; + } + + arch_align = pcibios_window_alignment(bus, type); + return max(align, arch_align); +} + /** * pbus_size_io() - size the io window of a given bus * @@ -717,17 +749,12 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size, struct resource *b_res = find_free_bus_resource(bus, IORESOURCE_IO); unsigned long size = 0, size0 = 0, size1 = 0; resource_size_t children_add_size = 0; - resource_size_t min_align = 4096, align; + resource_size_t min_align, io_align, align; if (!b_res) return; - /* - * Per spec, I/O windows are 4K-aligned, but some bridges have an - * extension to support 1K alignment. - */ - if (bus->self->io_window_1k) - min_align = 1024; + io_align = min_align = window_alignment(bus, IORESOURCE_IO); list_for_each_entry(dev, &bus->devices, bus_list) { int i; @@ -754,8 +781,8 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size, } } - if (min_align > 4096) - min_align = 4096; + if (min_align > io_align) + min_align = io_align; size0 = calculate_iosize(size, min_size, size1, resource_size(b_res), min_align); @@ -785,6 +812,28 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size, } } +static inline resource_size_t calculate_mem_align(resource_size_t *aligns, + int max_order) +{ + resource_size_t align = 0; + resource_size_t min_align = 0; + int order; + + for (order = 0; order <= max_order; order++) { + resource_size_t align1 = 1; + + align1 <<= (order + 20); + + if (!align) + min_align = align1; + else if (ALIGN(align + min_align, min_align) < align1) + min_align = align1 >> 1; + align += aligns[order]; + } + + return min_align; +} + /** * pbus_size_mem() - size the memory window of a given bus * @@ -864,19 +913,9 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask, children_add_size += get_res_add_size(realloc_head, r); } } - align = 0; - min_align = 0; - for (order = 0; order <= max_order; order++) { - resource_size_t align1 = 1; - align1 <<= (order + 20); - - if (!align) - min_align = align1; - else if (ALIGN(align + min_align, min_align) < align1) - min_align = align1 >> 1; - align += aligns[order]; - } + min_align = calculate_mem_align(aligns, max_order); + min_align = max(min_align, window_alignment(bus, b_res->flags & mask)); size0 = calculate_memsize(size, min_size, 0, resource_size(b_res), min_align); if (children_add_size > add_size) add_size = children_add_size; diff --git a/include/linux/pci.h b/include/linux/pci.h index 0d8718904e88..e52f16189cda 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -1061,6 +1061,8 @@ int pci_cfg_space_size_ext(struct pci_dev *dev); int pci_cfg_space_size(struct pci_dev *dev); unsigned char pci_bus_max_busnr(struct pci_bus *bus); void pci_setup_bridge(struct pci_bus *bus); +resource_size_t pcibios_window_alignment(struct pci_bus *bus, + unsigned long type); #define PCI_VGA_STATE_CHANGE_BRIDGE (1 << 0) #define PCI_VGA_STATE_CHANGE_DECODES (1 << 1) |