diff options
Diffstat (limited to 'drivers/pci/probe.c')
| -rw-r--r-- | drivers/pci/probe.c | 3377 |
1 files changed, 3377 insertions, 0 deletions
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c new file mode 100644 index 0000000000..43159965e0 --- /dev/null +++ b/drivers/pci/probe.c @@ -0,0 +1,3377 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PCI detection and setup code + */ + +#include <linux/kernel.h> +#include <linux/delay.h> +#include <linux/init.h> +#include <linux/pci.h> +#include <linux/msi.h> +#include <linux/of_pci.h> +#include <linux/pci_hotplug.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/cpumask.h> +#include <linux/aer.h> +#include <linux/acpi.h> +#include <linux/hypervisor.h> +#include <linux/irqdomain.h> +#include <linux/pm_runtime.h> +#include <linux/bitfield.h> +#include "pci.h" + +#define CARDBUS_LATENCY_TIMER 176 /* secondary latency timer */ +#define CARDBUS_RESERVE_BUSNR 3 + +static struct resource busn_resource = { + .name = "PCI busn", + .start = 0, + .end = 255, + .flags = IORESOURCE_BUS, +}; + +/* Ugh. Need to stop exporting this to modules. */ +LIST_HEAD(pci_root_buses); +EXPORT_SYMBOL(pci_root_buses); + +static LIST_HEAD(pci_domain_busn_res_list); + +struct pci_domain_busn_res { + struct list_head list; + struct resource res; + int domain_nr; +}; + +static struct resource *get_pci_domain_busn_res(int domain_nr) +{ + struct pci_domain_busn_res *r; + + list_for_each_entry(r, &pci_domain_busn_res_list, list) + if (r->domain_nr == domain_nr) + return &r->res; + + r = kzalloc(sizeof(*r), GFP_KERNEL); + if (!r) + return NULL; + + r->domain_nr = domain_nr; + r->res.start = 0; + r->res.end = 0xff; + r->res.flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED; + + list_add_tail(&r->list, &pci_domain_busn_res_list); + + return &r->res; +} + +/* + * Some device drivers need know if PCI is initiated. + * Basically, we think PCI is not initiated when there + * is no device to be found on the pci_bus_type. + */ +int no_pci_devices(void) +{ + struct device *dev; + int no_devices; + + dev = bus_find_next_device(&pci_bus_type, NULL); + no_devices = (dev == NULL); + put_device(dev); + return no_devices; +} +EXPORT_SYMBOL(no_pci_devices); + +/* + * PCI Bus Class + */ +static void release_pcibus_dev(struct device *dev) +{ + struct pci_bus *pci_bus = to_pci_bus(dev); + + put_device(pci_bus->bridge); + pci_bus_remove_resources(pci_bus); + pci_release_bus_of_node(pci_bus); + kfree(pci_bus); +} + +static struct class pcibus_class = { + .name = "pci_bus", + .dev_release = &release_pcibus_dev, + .dev_groups = pcibus_groups, +}; + +static int __init pcibus_class_init(void) +{ + return class_register(&pcibus_class); +} +postcore_initcall(pcibus_class_init); + +static u64 pci_size(u64 base, u64 maxbase, u64 mask) +{ + u64 size = mask & maxbase; /* Find the significant bits */ + if (!size) + return 0; + + /* + * Get the lowest of them to find the decode size, and from that + * the extent. + */ + size = size & ~(size-1); + + /* + * base == maxbase can be valid only if the BAR has already been + * programmed with all 1s. + */ + if (base == maxbase && ((base | (size - 1)) & mask) != mask) + return 0; + + return size; +} + +static inline unsigned long decode_bar(struct pci_dev *dev, u32 bar) +{ + u32 mem_type; + unsigned long flags; + + if ((bar & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO) { + flags = bar & ~PCI_BASE_ADDRESS_IO_MASK; + flags |= IORESOURCE_IO; + return flags; + } + + flags = bar & ~PCI_BASE_ADDRESS_MEM_MASK; + flags |= IORESOURCE_MEM; + if (flags & PCI_BASE_ADDRESS_MEM_PREFETCH) + flags |= IORESOURCE_PREFETCH; + + mem_type = bar & PCI_BASE_ADDRESS_MEM_TYPE_MASK; + switch (mem_type) { + case PCI_BASE_ADDRESS_MEM_TYPE_32: + break; + case PCI_BASE_ADDRESS_MEM_TYPE_1M: + /* 1M mem BAR treated as 32-bit BAR */ + break; + case PCI_BASE_ADDRESS_MEM_TYPE_64: + flags |= IORESOURCE_MEM_64; + break; + default: + /* mem unknown type treated as 32-bit BAR */ + break; + } + return flags; +} + +#define PCI_COMMAND_DECODE_ENABLE (PCI_COMMAND_MEMORY | PCI_COMMAND_IO) + +/** + * __pci_read_base - Read a PCI BAR + * @dev: the PCI device + * @type: type of the BAR + * @res: resource buffer to be filled in + * @pos: BAR position in the config space + * + * Returns 1 if the BAR is 64-bit, or 0 if 32-bit. + */ +int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type, + struct resource *res, unsigned int pos) +{ + u32 l = 0, sz = 0, mask; + u64 l64, sz64, mask64; + u16 orig_cmd; + struct pci_bus_region region, inverted_region; + + mask = type ? PCI_ROM_ADDRESS_MASK : ~0; + + /* No printks while decoding is disabled! */ + if (!dev->mmio_always_on) { + pci_read_config_word(dev, PCI_COMMAND, &orig_cmd); + if (orig_cmd & PCI_COMMAND_DECODE_ENABLE) { + pci_write_config_word(dev, PCI_COMMAND, + orig_cmd & ~PCI_COMMAND_DECODE_ENABLE); + } + } + + res->name = pci_name(dev); + + pci_read_config_dword(dev, pos, &l); + pci_write_config_dword(dev, pos, l | mask); + pci_read_config_dword(dev, pos, &sz); + pci_write_config_dword(dev, pos, l); + + /* + * All bits set in sz means the device isn't working properly. + * If the BAR isn't implemented, all bits must be 0. If it's a + * memory BAR or a ROM, bit 0 must be clear; if it's an io BAR, bit + * 1 must be clear. + */ + if (PCI_POSSIBLE_ERROR(sz)) + sz = 0; + + /* + * I don't know how l can have all bits set. Copied from old code. + * Maybe it fixes a bug on some ancient platform. + */ + if (PCI_POSSIBLE_ERROR(l)) + l = 0; + + if (type == pci_bar_unknown) { + res->flags = decode_bar(dev, l); + res->flags |= IORESOURCE_SIZEALIGN; + if (res->flags & IORESOURCE_IO) { + l64 = l & PCI_BASE_ADDRESS_IO_MASK; + sz64 = sz & PCI_BASE_ADDRESS_IO_MASK; + mask64 = PCI_BASE_ADDRESS_IO_MASK & (u32)IO_SPACE_LIMIT; + } else { + l64 = l & PCI_BASE_ADDRESS_MEM_MASK; + sz64 = sz & PCI_BASE_ADDRESS_MEM_MASK; + mask64 = (u32)PCI_BASE_ADDRESS_MEM_MASK; + } + } else { + if (l & PCI_ROM_ADDRESS_ENABLE) + res->flags |= IORESOURCE_ROM_ENABLE; + l64 = l & PCI_ROM_ADDRESS_MASK; + sz64 = sz & PCI_ROM_ADDRESS_MASK; + mask64 = PCI_ROM_ADDRESS_MASK; + } + + if (res->flags & IORESOURCE_MEM_64) { + pci_read_config_dword(dev, pos + 4, &l); + pci_write_config_dword(dev, pos + 4, ~0); + pci_read_config_dword(dev, pos + 4, &sz); + pci_write_config_dword(dev, pos + 4, l); + + l64 |= ((u64)l << 32); + sz64 |= ((u64)sz << 32); + mask64 |= ((u64)~0 << 32); + } + + if (!dev->mmio_always_on && (orig_cmd & PCI_COMMAND_DECODE_ENABLE)) + pci_write_config_word(dev, PCI_COMMAND, orig_cmd); + + if (!sz64) + goto fail; + + sz64 = pci_size(l64, sz64, mask64); + if (!sz64) { + pci_info(dev, FW_BUG "reg 0x%x: invalid BAR (can't size)\n", + pos); + goto fail; + } + + if (res->flags & IORESOURCE_MEM_64) { + if ((sizeof(pci_bus_addr_t) < 8 || sizeof(resource_size_t) < 8) + && sz64 > 0x100000000ULL) { + res->flags |= IORESOURCE_UNSET | IORESOURCE_DISABLED; + res->start = 0; + res->end = 0; + pci_err(dev, "reg 0x%x: can't handle BAR larger than 4GB (size %#010llx)\n", + pos, (unsigned long long)sz64); + goto out; + } + + if ((sizeof(pci_bus_addr_t) < 8) && l) { + /* Above 32-bit boundary; try to reallocate */ + res->flags |= IORESOURCE_UNSET; + res->start = 0; + res->end = sz64 - 1; + pci_info(dev, "reg 0x%x: can't handle BAR above 4GB (bus address %#010llx)\n", + pos, (unsigned long long)l64); + goto out; + } + } + + region.start = l64; + region.end = l64 + sz64 - 1; + + pcibios_bus_to_resource(dev->bus, res, ®ion); + pcibios_resource_to_bus(dev->bus, &inverted_region, res); + + /* + * If "A" is a BAR value (a bus address), "bus_to_resource(A)" is + * the corresponding resource address (the physical address used by + * the CPU. Converting that resource address back to a bus address + * should yield the original BAR value: + * + * resource_to_bus(bus_to_resource(A)) == A + * + * If it doesn't, CPU accesses to "bus_to_resource(A)" will not + * be claimed by the device. + */ + if (inverted_region.start != region.start) { + res->flags |= IORESOURCE_UNSET; + res->start = 0; + res->end = region.end - region.start; + pci_info(dev, "reg 0x%x: initial BAR value %#010llx invalid\n", + pos, (unsigned long long)region.start); + } + + goto out; + + +fail: + res->flags = 0; +out: + if (res->flags) + pci_info(dev, "reg 0x%x: %pR\n", pos, res); + + return (res->flags & IORESOURCE_MEM_64) ? 1 : 0; +} + +static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom) +{ + unsigned int pos, reg; + + if (dev->non_compliant_bars) + return; + + /* Per PCIe r4.0, sec 9.3.4.1.11, the VF BARs are all RO Zero */ + if (dev->is_virtfn) + return; + + for (pos = 0; pos < howmany; pos++) { + struct resource *res = &dev->resource[pos]; + reg = PCI_BASE_ADDRESS_0 + (pos << 2); + pos += __pci_read_base(dev, pci_bar_unknown, res, reg); + } + + if (rom) { + struct resource *res = &dev->resource[PCI_ROM_RESOURCE]; + dev->rom_base_reg = rom; + res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH | + IORESOURCE_READONLY | IORESOURCE_SIZEALIGN; + __pci_read_base(dev, pci_bar_mem32, res, rom); + } +} + +static void pci_read_bridge_windows(struct pci_dev *bridge) +{ + u16 io; + u32 pmem, tmp; + + pci_read_config_word(bridge, PCI_IO_BASE, &io); + if (!io) { + pci_write_config_word(bridge, PCI_IO_BASE, 0xe0f0); + pci_read_config_word(bridge, PCI_IO_BASE, &io); + pci_write_config_word(bridge, PCI_IO_BASE, 0x0); + } + if (io) + bridge->io_window = 1; + + /* + * DECchip 21050 pass 2 errata: the bridge may miss an address + * disconnect boundary by one PCI data phase. Workaround: do not + * use prefetching on this device. + */ + if (bridge->vendor == PCI_VENDOR_ID_DEC && bridge->device == 0x0001) + return; + + pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem); + if (!pmem) { + pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, + 0xffe0fff0); + pci_read_config_dword(bridge, PCI_PREF_MEMORY_BASE, &pmem); + pci_write_config_dword(bridge, PCI_PREF_MEMORY_BASE, 0x0); + } + if (!pmem) + return; + + bridge->pref_window = 1; + + if ((pmem & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) { + + /* + * Bridge claims to have a 64-bit prefetchable memory + * window; verify that the upper bits are actually + * writable. + */ + pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &pmem); + pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, + 0xffffffff); + pci_read_config_dword(bridge, PCI_PREF_BASE_UPPER32, &tmp); + pci_write_config_dword(bridge, PCI_PREF_BASE_UPPER32, pmem); + if (tmp) + bridge->pref_64_window = 1; + } +} + +static void pci_read_bridge_io(struct pci_bus *child) +{ + struct pci_dev *dev = child->self; + u8 io_base_lo, io_limit_lo; + unsigned long io_mask, io_granularity, base, limit; + struct pci_bus_region region; + struct resource *res; + + io_mask = PCI_IO_RANGE_MASK; + io_granularity = 0x1000; + if (dev->io_window_1k) { + /* Support 1K I/O space granularity */ + io_mask = PCI_IO_1K_RANGE_MASK; + io_granularity = 0x400; + } + + res = child->resource[0]; + pci_read_config_byte(dev, PCI_IO_BASE, &io_base_lo); + pci_read_config_byte(dev, PCI_IO_LIMIT, &io_limit_lo); + base = (io_base_lo & io_mask) << 8; + limit = (io_limit_lo & io_mask) << 8; + + if ((io_base_lo & PCI_IO_RANGE_TYPE_MASK) == PCI_IO_RANGE_TYPE_32) { + u16 io_base_hi, io_limit_hi; + + pci_read_config_word(dev, PCI_IO_BASE_UPPER16, &io_base_hi); + pci_read_config_word(dev, PCI_IO_LIMIT_UPPER16, &io_limit_hi); + base |= ((unsigned long) io_base_hi << 16); + limit |= ((unsigned long) io_limit_hi << 16); + } + + if (base <= limit) { + res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO; + region.start = base; + region.end = limit + io_granularity - 1; + pcibios_bus_to_resource(dev->bus, res, ®ion); + pci_info(dev, " bridge window %pR\n", res); + } +} + +static void pci_read_bridge_mmio(struct pci_bus *child) +{ + struct pci_dev *dev = child->self; + u16 mem_base_lo, mem_limit_lo; + unsigned long base, limit; + struct pci_bus_region region; + struct resource *res; + + res = child->resource[1]; + pci_read_config_word(dev, PCI_MEMORY_BASE, &mem_base_lo); + pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo); + base = ((unsigned long) mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16; + limit = ((unsigned long) mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16; + if (base <= limit) { + res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM; + region.start = base; + region.end = limit + 0xfffff; + pcibios_bus_to_resource(dev->bus, res, ®ion); + pci_info(dev, " bridge window %pR\n", res); + } +} + +static void pci_read_bridge_mmio_pref(struct pci_bus *child) +{ + struct pci_dev *dev = child->self; + u16 mem_base_lo, mem_limit_lo; + u64 base64, limit64; + pci_bus_addr_t base, limit; + struct pci_bus_region region; + struct resource *res; + + res = child->resource[2]; + pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo); + pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo); + base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16; + limit64 = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16; + + if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) { + u32 mem_base_hi, mem_limit_hi; + + pci_read_config_dword(dev, PCI_PREF_BASE_UPPER32, &mem_base_hi); + pci_read_config_dword(dev, PCI_PREF_LIMIT_UPPER32, &mem_limit_hi); + + /* + * Some bridges set the base > limit by default, and some + * (broken) BIOSes do not initialize them. If we find + * this, just assume they are not being used. + */ + if (mem_base_hi <= mem_limit_hi) { + base64 |= (u64) mem_base_hi << 32; + limit64 |= (u64) mem_limit_hi << 32; + } + } + + base = (pci_bus_addr_t) base64; + limit = (pci_bus_addr_t) limit64; + + if (base != base64) { + pci_err(dev, "can't handle bridge window above 4GB (bus address %#010llx)\n", + (unsigned long long) base64); + return; + } + + if (base <= limit) { + res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) | + IORESOURCE_MEM | IORESOURCE_PREFETCH; + if (res->flags & PCI_PREF_RANGE_TYPE_64) + res->flags |= IORESOURCE_MEM_64; + region.start = base; + region.end = limit + 0xfffff; + pcibios_bus_to_resource(dev->bus, res, ®ion); + pci_info(dev, " bridge window %pR\n", res); + } +} + +void pci_read_bridge_bases(struct pci_bus *child) +{ + struct pci_dev *dev = child->self; + struct resource *res; + int i; + + if (pci_is_root_bus(child)) /* It's a host bus, nothing to read */ + return; + + pci_info(dev, "PCI bridge to %pR%s\n", + &child->busn_res, + dev->transparent ? " (subtractive decode)" : ""); + + pci_bus_remove_resources(child); + for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) + child->resource[i] = &dev->resource[PCI_BRIDGE_RESOURCES+i]; + + pci_read_bridge_io(child); + pci_read_bridge_mmio(child); + pci_read_bridge_mmio_pref(child); + + if (dev->transparent) { + pci_bus_for_each_resource(child->parent, res) { + if (res && res->flags) { + pci_bus_add_resource(child, res, + PCI_SUBTRACTIVE_DECODE); + pci_info(dev, " bridge window %pR (subtractive decode)\n", + res); + } + } + } +} + +static struct pci_bus *pci_alloc_bus(struct pci_bus *parent) +{ + struct pci_bus *b; + + b = kzalloc(sizeof(*b), GFP_KERNEL); + if (!b) + return NULL; + + INIT_LIST_HEAD(&b->node); + INIT_LIST_HEAD(&b->children); + INIT_LIST_HEAD(&b->devices); + INIT_LIST_HEAD(&b->slots); + INIT_LIST_HEAD(&b->resources); + b->max_bus_speed = PCI_SPEED_UNKNOWN; + b->cur_bus_speed = PCI_SPEED_UNKNOWN; +#ifdef CONFIG_PCI_DOMAINS_GENERIC + if (parent) + b->domain_nr = parent->domain_nr; +#endif + return b; +} + +static void pci_release_host_bridge_dev(struct device *dev) +{ + struct pci_host_bridge *bridge = to_pci_host_bridge(dev); + + if (bridge->release_fn) + bridge->release_fn(bridge); + + pci_free_resource_list(&bridge->windows); + pci_free_resource_list(&bridge->dma_ranges); + kfree(bridge); +} + +static void pci_init_host_bridge(struct pci_host_bridge *bridge) +{ + INIT_LIST_HEAD(&bridge->windows); + INIT_LIST_HEAD(&bridge->dma_ranges); + + /* + * We assume we can manage these PCIe features. Some systems may + * reserve these for use by the platform itself, e.g., an ACPI BIOS + * may implement its own AER handling and use _OSC to prevent the + * OS from interfering. + */ + bridge->native_aer = 1; + bridge->native_pcie_hotplug = 1; + bridge->native_shpc_hotplug = 1; + bridge->native_pme = 1; + bridge->native_ltr = 1; + bridge->native_dpc = 1; + bridge->domain_nr = PCI_DOMAIN_NR_NOT_SET; + bridge->native_cxl_error = 1; + + device_initialize(&bridge->dev); +} + +struct pci_host_bridge *pci_alloc_host_bridge(size_t priv) +{ + struct pci_host_bridge *bridge; + + bridge = kzalloc(sizeof(*bridge) + priv, GFP_KERNEL); + if (!bridge) + return NULL; + + pci_init_host_bridge(bridge); + bridge->dev.release = pci_release_host_bridge_dev; + + return bridge; +} +EXPORT_SYMBOL(pci_alloc_host_bridge); + +static void devm_pci_alloc_host_bridge_release(void *data) +{ + pci_free_host_bridge(data); +} + +struct pci_host_bridge *devm_pci_alloc_host_bridge(struct device *dev, + size_t priv) +{ + int ret; + struct pci_host_bridge *bridge; + + bridge = pci_alloc_host_bridge(priv); + if (!bridge) + return NULL; + + bridge->dev.parent = dev; + + ret = devm_add_action_or_reset(dev, devm_pci_alloc_host_bridge_release, + bridge); + if (ret) + return NULL; + + ret = devm_of_pci_bridge_init(dev, bridge); + if (ret) + return NULL; + + return bridge; +} +EXPORT_SYMBOL(devm_pci_alloc_host_bridge); + +void pci_free_host_bridge(struct pci_host_bridge *bridge) +{ + put_device(&bridge->dev); +} +EXPORT_SYMBOL(pci_free_host_bridge); + +/* Indexed by PCI_X_SSTATUS_FREQ (secondary bus mode and frequency) */ +static const unsigned char pcix_bus_speed[] = { + PCI_SPEED_UNKNOWN, /* 0 */ + PCI_SPEED_66MHz_PCIX, /* 1 */ + PCI_SPEED_100MHz_PCIX, /* 2 */ + PCI_SPEED_133MHz_PCIX, /* 3 */ + PCI_SPEED_UNKNOWN, /* 4 */ + PCI_SPEED_66MHz_PCIX_ECC, /* 5 */ + PCI_SPEED_100MHz_PCIX_ECC, /* 6 */ + PCI_SPEED_133MHz_PCIX_ECC, /* 7 */ + PCI_SPEED_UNKNOWN, /* 8 */ + PCI_SPEED_66MHz_PCIX_266, /* 9 */ + PCI_SPEED_100MHz_PCIX_266, /* A */ + PCI_SPEED_133MHz_PCIX_266, /* B */ + PCI_SPEED_UNKNOWN, /* C */ + PCI_SPEED_66MHz_PCIX_533, /* D */ + PCI_SPEED_100MHz_PCIX_533, /* E */ + PCI_SPEED_133MHz_PCIX_533 /* F */ +}; + +/* Indexed by PCI_EXP_LNKCAP_SLS, PCI_EXP_LNKSTA_CLS */ +const unsigned char pcie_link_speed[] = { + PCI_SPEED_UNKNOWN, /* 0 */ + PCIE_SPEED_2_5GT, /* 1 */ + PCIE_SPEED_5_0GT, /* 2 */ + PCIE_SPEED_8_0GT, /* 3 */ + PCIE_SPEED_16_0GT, /* 4 */ + PCIE_SPEED_32_0GT, /* 5 */ + PCIE_SPEED_64_0GT, /* 6 */ + PCI_SPEED_UNKNOWN, /* 7 */ + PCI_SPEED_UNKNOWN, /* 8 */ + PCI_SPEED_UNKNOWN, /* 9 */ + PCI_SPEED_UNKNOWN, /* A */ + PCI_SPEED_UNKNOWN, /* B */ + PCI_SPEED_UNKNOWN, /* C */ + PCI_SPEED_UNKNOWN, /* D */ + PCI_SPEED_UNKNOWN, /* E */ + PCI_SPEED_UNKNOWN /* F */ +}; +EXPORT_SYMBOL_GPL(pcie_link_speed); + +const char *pci_speed_string(enum pci_bus_speed speed) +{ + /* Indexed by the pci_bus_speed enum */ + static const char *speed_strings[] = { + "33 MHz PCI", /* 0x00 */ + "66 MHz PCI", /* 0x01 */ + "66 MHz PCI-X", /* 0x02 */ + "100 MHz PCI-X", /* 0x03 */ + "133 MHz PCI-X", /* 0x04 */ + NULL, /* 0x05 */ + NULL, /* 0x06 */ + NULL, /* 0x07 */ + NULL, /* 0x08 */ + "66 MHz PCI-X 266", /* 0x09 */ + "100 MHz PCI-X 266", /* 0x0a */ + "133 MHz PCI-X 266", /* 0x0b */ + "Unknown AGP", /* 0x0c */ + "1x AGP", /* 0x0d */ + "2x AGP", /* 0x0e */ + "4x AGP", /* 0x0f */ + "8x AGP", /* 0x10 */ + "66 MHz PCI-X 533", /* 0x11 */ + "100 MHz PCI-X 533", /* 0x12 */ + "133 MHz PCI-X 533", /* 0x13 */ + "2.5 GT/s PCIe", /* 0x14 */ + "5.0 GT/s PCIe", /* 0x15 */ + "8.0 GT/s PCIe", /* 0x16 */ + "16.0 GT/s PCIe", /* 0x17 */ + "32.0 GT/s PCIe", /* 0x18 */ + "64.0 GT/s PCIe", /* 0x19 */ + }; + + if (speed < ARRAY_SIZE(speed_strings)) + return speed_strings[speed]; + return "Unknown"; +} +EXPORT_SYMBOL_GPL(pci_speed_string); + +void pcie_update_link_speed(struct pci_bus *bus, u16 linksta) +{ + bus->cur_bus_speed = pcie_link_speed[linksta & PCI_EXP_LNKSTA_CLS]; +} +EXPORT_SYMBOL_GPL(pcie_update_link_speed); + +static unsigned char agp_speeds[] = { + AGP_UNKNOWN, + AGP_1X, + AGP_2X, + AGP_4X, + AGP_8X +}; + +static enum pci_bus_speed agp_speed(int agp3, int agpstat) +{ + int index = 0; + + if (agpstat & 4) + index = 3; + else if (agpstat & 2) + index = 2; + else if (agpstat & 1) + index = 1; + else + goto out; + + if (agp3) { + index += 2; + if (index == 5) + index = 0; + } + + out: + return agp_speeds[index]; +} + +static void pci_set_bus_speed(struct pci_bus *bus) +{ + struct pci_dev *bridge = bus->self; + int pos; + + pos = pci_find_capability(bridge, PCI_CAP_ID_AGP); + if (!pos) + pos = pci_find_capability(bridge, PCI_CAP_ID_AGP3); + if (pos) { + u32 agpstat, agpcmd; + + pci_read_config_dword(bridge, pos + PCI_AGP_STATUS, &agpstat); + bus->max_bus_speed = agp_speed(agpstat & 8, agpstat & 7); + + pci_read_config_dword(bridge, pos + PCI_AGP_COMMAND, &agpcmd); + bus->cur_bus_speed = agp_speed(agpstat & 8, agpcmd & 7); + } + + pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX); + if (pos) { + u16 status; + enum pci_bus_speed max; + + pci_read_config_word(bridge, pos + PCI_X_BRIDGE_SSTATUS, + &status); + + if (status & PCI_X_SSTATUS_533MHZ) { + max = PCI_SPEED_133MHz_PCIX_533; + } else if (status & PCI_X_SSTATUS_266MHZ) { + max = PCI_SPEED_133MHz_PCIX_266; + } else if (status & PCI_X_SSTATUS_133MHZ) { + if ((status & PCI_X_SSTATUS_VERS) == PCI_X_SSTATUS_V2) + max = PCI_SPEED_133MHz_PCIX_ECC; + else + max = PCI_SPEED_133MHz_PCIX; + } else { + max = PCI_SPEED_66MHz_PCIX; + } + + bus->max_bus_speed = max; + bus->cur_bus_speed = pcix_bus_speed[ + (status & PCI_X_SSTATUS_FREQ) >> 6]; + + return; + } + + if (pci_is_pcie(bridge)) { + u32 linkcap; + u16 linksta; + + pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap); + bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS]; + + pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta); + pcie_update_link_speed(bus, linksta); + } +} + +static struct irq_domain *pci_host_bridge_msi_domain(struct pci_bus *bus) +{ + struct irq_domain *d; + + /* If the host bridge driver sets a MSI domain of the bridge, use it */ + d = dev_get_msi_domain(bus->bridge); + + /* + * Any firmware interface that can resolve the msi_domain + * should be called from here. + */ + if (!d) + d = pci_host_bridge_of_msi_domain(bus); + if (!d) + d = pci_host_bridge_acpi_msi_domain(bus); + + /* + * If no IRQ domain was found via the OF tree, try looking it up + * directly through the fwnode_handle. + */ + if (!d) { + struct fwnode_handle *fwnode = pci_root_bus_fwnode(bus); + + if (fwnode) + d = irq_find_matching_fwnode(fwnode, + DOMAIN_BUS_PCI_MSI); + } + + return d; +} + +static void pci_set_bus_msi_domain(struct pci_bus *bus) +{ + struct irq_domain *d; + struct pci_bus *b; + + /* + * The bus can be a root bus, a subordinate bus, or a virtual bus + * created by an SR-IOV device. Walk up to the first bridge device + * found or derive the domain from the host bridge. + */ + for (b = bus, d = NULL; !d && !pci_is_root_bus(b); b = b->parent) { + if (b->self) + d = dev_get_msi_domain(&b->self->dev); + } + + if (!d) + d = pci_host_bridge_msi_domain(b); + + dev_set_msi_domain(&bus->dev, d); +} + +static int pci_register_host_bridge(struct pci_host_bridge *bridge) +{ + struct device *parent = bridge->dev.parent; + struct resource_entry *window, *next, *n; + struct pci_bus *bus, *b; + resource_size_t offset, next_offset; + LIST_HEAD(resources); + struct resource *res, *next_res; + char addr[64], *fmt; + const char *name; + int err; + + bus = pci_alloc_bus(NULL); + if (!bus) + return -ENOMEM; + + bridge->bus = bus; + + bus->sysdata = bridge->sysdata; + bus->ops = bridge->ops; + bus->number = bus->busn_res.start = bridge->busnr; +#ifdef CONFIG_PCI_DOMAINS_GENERIC + if (bridge->domain_nr == PCI_DOMAIN_NR_NOT_SET) + bus->domain_nr = pci_bus_find_domain_nr(bus, parent); + else + bus->domain_nr = bridge->domain_nr; + if (bus->domain_nr < 0) { + err = bus->domain_nr; + goto free; + } +#endif + + b = pci_find_bus(pci_domain_nr(bus), bridge->busnr); + if (b) { + /* Ignore it if we already got here via a different bridge */ + dev_dbg(&b->dev, "bus already known\n"); + err = -EEXIST; + goto free; + } + + dev_set_name(&bridge->dev, "pci%04x:%02x", pci_domain_nr(bus), + bridge->busnr); + + err = pcibios_root_bridge_prepare(bridge); + if (err) + goto free; + + /* Temporarily move resources off the list */ + list_splice_init(&bridge->windows, &resources); + err = device_add(&bridge->dev); + if (err) { + put_device(&bridge->dev); + goto free; + } + bus->bridge = get_device(&bridge->dev); + device_enable_async_suspend(bus->bridge); + pci_set_bus_of_node(bus); + pci_set_bus_msi_domain(bus); + if (bridge->msi_domain && !dev_get_msi_domain(&bus->dev) && + !pci_host_of_has_msi_map(parent)) + bus->bus_flags |= PCI_BUS_FLAGS_NO_MSI; + + if (!parent) + set_dev_node(bus->bridge, pcibus_to_node(bus)); + + bus->dev.class = &pcibus_class; + bus->dev.parent = bus->bridge; + + dev_set_name(&bus->dev, "%04x:%02x", pci_domain_nr(bus), bus->number); + name = dev_name(&bus->dev); + + err = device_register(&bus->dev); + if (err) + goto unregister; + + pcibios_add_bus(bus); + + if (bus->ops->add_bus) { + err = bus->ops->add_bus(bus); + if (WARN_ON(err < 0)) + dev_err(&bus->dev, "failed to add bus: %d\n", err); + } + + /* Create legacy_io and legacy_mem files for this bus */ + pci_create_legacy_files(bus); + + if (parent) + dev_info(parent, "PCI host bridge to bus %s\n", name); + else + pr_info("PCI host bridge to bus %s\n", name); + + if (nr_node_ids > 1 && pcibus_to_node(bus) == NUMA_NO_NODE) + dev_warn(&bus->dev, "Unknown NUMA node; performance will be reduced\n"); + + /* Coalesce contiguous windows */ + resource_list_for_each_entry_safe(window, n, &resources) { + if (list_is_last(&window->node, &resources)) + break; + + next = list_next_entry(window, node); + offset = window->offset; + res = window->res; + next_offset = next->offset; + next_res = next->res; + + if (res->flags != next_res->flags || offset != next_offset) + continue; + + if (res->end + 1 == next_res->start) { + next_res->start = res->start; + res->flags = res->start = res->end = 0; + } + } + + /* Add initial resources to the bus */ + resource_list_for_each_entry_safe(window, n, &resources) { + offset = window->offset; + res = window->res; + if (!res->flags && !res->start && !res->end) { + release_resource(res); + resource_list_destroy_entry(window); + continue; + } + + list_move_tail(&window->node, &bridge->windows); + + if (res->flags & IORESOURCE_BUS) + pci_bus_insert_busn_res(bus, bus->number, res->end); + else + pci_bus_add_resource(bus, res, 0); + + if (offset) { + if (resource_type(res) == IORESOURCE_IO) + fmt = " (bus address [%#06llx-%#06llx])"; + else + fmt = " (bus address [%#010llx-%#010llx])"; + + snprintf(addr, sizeof(addr), fmt, + (unsigned long long)(res->start - offset), + (unsigned long long)(res->end - offset)); + } else + addr[0] = '\0'; + + dev_info(&bus->dev, "root bus resource %pR%s\n", res, addr); + } + + down_write(&pci_bus_sem); + list_add_tail(&bus->node, &pci_root_buses); + up_write(&pci_bus_sem); + + return 0; + +unregister: + put_device(&bridge->dev); + device_del(&bridge->dev); + +free: +#ifdef CONFIG_PCI_DOMAINS_GENERIC + pci_bus_release_domain_nr(bus, parent); +#endif + kfree(bus); + return err; +} + +static bool pci_bridge_child_ext_cfg_accessible(struct pci_dev *bridge) +{ + int pos; + u32 status; + + /* + * If extended config space isn't accessible on a bridge's primary + * bus, we certainly can't access it on the secondary bus. + */ + if (bridge->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG) + return false; + + /* + * PCIe Root Ports and switch ports are PCIe on both sides, so if + * extended config space is accessible on the primary, it's also + * accessible on the secondary. + */ + if (pci_is_pcie(bridge) && + (pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT || + pci_pcie_type(bridge) == PCI_EXP_TYPE_UPSTREAM || + pci_pcie_type(bridge) == PCI_EXP_TYPE_DOWNSTREAM)) + return true; + + /* + * For the other bridge types: + * - PCI-to-PCI bridges + * - PCIe-to-PCI/PCI-X forward bridges + * - PCI/PCI-X-to-PCIe reverse bridges + * extended config space on the secondary side is only accessible + * if the bridge supports PCI-X Mode 2. + */ + pos = pci_find_capability(bridge, PCI_CAP_ID_PCIX); + if (!pos) + return false; + + pci_read_config_dword(bridge, pos + PCI_X_STATUS, &status); + return status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ); +} + +static struct pci_bus *pci_alloc_child_bus(struct pci_bus *parent, + struct pci_dev *bridge, int busnr) +{ + struct pci_bus *child; + struct pci_host_bridge *host; + int i; + int ret; + + /* Allocate a new bus and inherit stuff from the parent */ + child = pci_alloc_bus(parent); + if (!child) + return NULL; + + child->parent = parent; + child->sysdata = parent->sysdata; + child->bus_flags = parent->bus_flags; + + host = pci_find_host_bridge(parent); + if (host->child_ops) + child->ops = host->child_ops; + else + child->ops = parent->ops; + + /* + * Initialize some portions of the bus device, but don't register + * it now as the parent is not properly set up yet. + */ + child->dev.class = &pcibus_class; + dev_set_name(&child->dev, "%04x:%02x", pci_domain_nr(child), busnr); + + /* Set up the primary, secondary and subordinate bus numbers */ + child->number = child->busn_res.start = busnr; + child->primary = parent->busn_res.start; + child->busn_res.end = 0xff; + + if (!bridge) { + child->dev.parent = parent->bridge; + goto add_dev; + } + + child->self = bridge; + child->bridge = get_device(&bridge->dev); + child->dev.parent = child->bridge; + pci_set_bus_of_node(child); + pci_set_bus_speed(child); + + /* + * Check whether extended config space is accessible on the child + * bus. Note that we currently assume it is always accessible on + * the root bus. + */ + if (!pci_bridge_child_ext_cfg_accessible(bridge)) { + child->bus_flags |= PCI_BUS_FLAGS_NO_EXTCFG; + pci_info(child, "extended config space not accessible\n"); + } + + /* Set up default resource pointers and names */ + for (i = 0; i < PCI_BRIDGE_RESOURCE_NUM; i++) { + child->resource[i] = &bridge->resource[PCI_BRIDGE_RESOURCES+i]; + child->resource[i]->name = child->name; + } + bridge->subordinate = child; + +add_dev: + pci_set_bus_msi_domain(child); + ret = device_register(&child->dev); + WARN_ON(ret < 0); + + pcibios_add_bus(child); + + if (child->ops->add_bus) { + ret = child->ops->add_bus(child); + if (WARN_ON(ret < 0)) + dev_err(&child->dev, "failed to add bus: %d\n", ret); + } + + /* Create legacy_io and legacy_mem files for this bus */ + pci_create_legacy_files(child); + + return child; +} + +struct pci_bus *pci_add_new_bus(struct pci_bus *parent, struct pci_dev *dev, + int busnr) +{ + struct pci_bus *child; + + child = pci_alloc_child_bus(parent, dev, busnr); + if (child) { + down_write(&pci_bus_sem); + list_add_tail(&child->node, &parent->children); + up_write(&pci_bus_sem); + } + return child; +} +EXPORT_SYMBOL(pci_add_new_bus); + +static void pci_enable_crs(struct pci_dev *pdev) +{ + u16 root_cap = 0; + + /* Enable CRS Software Visibility if supported */ + pcie_capability_read_word(pdev, PCI_EXP_RTCAP, &root_cap); + if (root_cap & PCI_EXP_RTCAP_CRSVIS) + pcie_capability_set_word(pdev, PCI_EXP_RTCTL, + PCI_EXP_RTCTL_CRSSVE); +} + +static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus, + unsigned int available_buses); +/** + * pci_ea_fixed_busnrs() - Read fixed Secondary and Subordinate bus + * numbers from EA capability. + * @dev: Bridge + * @sec: updated with secondary bus number from EA + * @sub: updated with subordinate bus number from EA + * + * If @dev is a bridge with EA capability that specifies valid secondary + * and subordinate bus numbers, return true with the bus numbers in @sec + * and @sub. Otherwise return false. + */ +static bool pci_ea_fixed_busnrs(struct pci_dev *dev, u8 *sec, u8 *sub) +{ + int ea, offset; + u32 dw; + u8 ea_sec, ea_sub; + + if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) + return false; + + /* find PCI EA capability in list */ + ea = pci_find_capability(dev, PCI_CAP_ID_EA); + if (!ea) + return false; + + offset = ea + PCI_EA_FIRST_ENT; + pci_read_config_dword(dev, offset, &dw); + ea_sec = dw & PCI_EA_SEC_BUS_MASK; + ea_sub = (dw & PCI_EA_SUB_BUS_MASK) >> PCI_EA_SUB_BUS_SHIFT; + if (ea_sec == 0 || ea_sub < ea_sec) + return false; + + *sec = ea_sec; + *sub = ea_sub; + return true; +} + +/* + * pci_scan_bridge_extend() - Scan buses behind a bridge + * @bus: Parent bus the bridge is on + * @dev: Bridge itself + * @max: Starting subordinate number of buses behind this bridge + * @available_buses: Total number of buses available for this bridge and + * the devices below. After the minimal bus space has + * been allocated the remaining buses will be + * distributed equally between hotplug-capable bridges. + * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges + * that need to be reconfigured. + * + * If it's a bridge, configure it and scan the bus behind it. + * For CardBus bridges, we don't scan behind as the devices will + * be handled by the bridge driver itself. + * + * We need to process bridges in two passes -- first we scan those + * already configured by the BIOS and after we are done with all of + * them, we proceed to assigning numbers to the remaining buses in + * order to avoid overlaps between old and new bus numbers. + * + * Return: New subordinate number covering all buses behind this bridge. + */ +static int pci_scan_bridge_extend(struct pci_bus *bus, struct pci_dev *dev, + int max, unsigned int available_buses, + int pass) +{ + struct pci_bus *child; + int is_cardbus = (dev->hdr_type == PCI_HEADER_TYPE_CARDBUS); + u32 buses, i, j = 0; + u16 bctl; + u8 primary, secondary, subordinate; + int broken = 0; + bool fixed_buses; + u8 fixed_sec, fixed_sub; + int next_busnr; + + /* + * Make sure the bridge is powered on to be able to access config + * space of devices below it. + */ + pm_runtime_get_sync(&dev->dev); + + pci_read_config_dword(dev, PCI_PRIMARY_BUS, &buses); + primary = buses & 0xFF; + secondary = (buses >> 8) & 0xFF; + subordinate = (buses >> 16) & 0xFF; + + pci_dbg(dev, "scanning [bus %02x-%02x] behind bridge, pass %d\n", + secondary, subordinate, pass); + + if (!primary && (primary != bus->number) && secondary && subordinate) { + pci_warn(dev, "Primary bus is hard wired to 0\n"); + primary = bus->number; + } + + /* Check if setup is sensible at all */ + if (!pass && + (primary != bus->number || secondary <= bus->number || + secondary > subordinate)) { + pci_info(dev, "bridge configuration invalid ([bus %02x-%02x]), reconfiguring\n", + secondary, subordinate); + broken = 1; + } + + /* + * Disable Master-Abort Mode during probing to avoid reporting of + * bus errors in some architectures. + */ + pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &bctl); + pci_write_config_word(dev, PCI_BRIDGE_CONTROL, + bctl & ~PCI_BRIDGE_CTL_MASTER_ABORT); + + pci_enable_crs(dev); + + if ((secondary || subordinate) && !pcibios_assign_all_busses() && + !is_cardbus && !broken) { + unsigned int cmax, buses; + + /* + * Bus already configured by firmware, process it in the + * first pass and just note the configuration. + */ + if (pass) + goto out; + + /* + * The bus might already exist for two reasons: Either we + * are rescanning the bus or the bus is reachable through + * more than one bridge. The second case can happen with + * the i450NX chipset. + */ + child = pci_find_bus(pci_domain_nr(bus), secondary); + if (!child) { + child = pci_add_new_bus(bus, dev, secondary); + if (!child) + goto out; + child->primary = primary; + pci_bus_insert_busn_res(child, secondary, subordinate); + child->bridge_ctl = bctl; + } + + buses = subordinate - secondary; + cmax = pci_scan_child_bus_extend(child, buses); + if (cmax > subordinate) + pci_warn(dev, "bridge has subordinate %02x but max busn %02x\n", + subordinate, cmax); + + /* Subordinate should equal child->busn_res.end */ + if (subordinate > max) + max = subordinate; + } else { + + /* + * We need to assign a number to this bus which we always + * do in the second pass. + */ + if (!pass) { + if (pcibios_assign_all_busses() || broken || is_cardbus) + + /* + * Temporarily disable forwarding of the + * configuration cycles on all bridges in + * this bus segment to avoid possible + * conflicts in the second pass between two + * bridges programmed with overlapping bus + * ranges. + */ + pci_write_config_dword(dev, PCI_PRIMARY_BUS, + buses & ~0xffffff); + goto out; + } + + /* Clear errors */ + pci_write_config_word(dev, PCI_STATUS, 0xffff); + + /* Read bus numbers from EA Capability (if present) */ + fixed_buses = pci_ea_fixed_busnrs(dev, &fixed_sec, &fixed_sub); + if (fixed_buses) + next_busnr = fixed_sec; + else + next_busnr = max + 1; + + /* + * Prevent assigning a bus number that already exists. + * This can happen when a bridge is hot-plugged, so in this + * case we only re-scan this bus. + */ + child = pci_find_bus(pci_domain_nr(bus), next_busnr); + if (!child) { + child = pci_add_new_bus(bus, dev, next_busnr); + if (!child) + goto out; + pci_bus_insert_busn_res(child, next_busnr, + bus->busn_res.end); + } + max++; + if (available_buses) + available_buses--; + + buses = (buses & 0xff000000) + | ((unsigned int)(child->primary) << 0) + | ((unsigned int)(child->busn_res.start) << 8) + | ((unsigned int)(child->busn_res.end) << 16); + + /* + * yenta.c forces a secondary latency timer of 176. + * Copy that behaviour here. + */ + if (is_cardbus) { + buses &= ~0xff000000; + buses |= CARDBUS_LATENCY_TIMER << 24; + } + + /* We need to blast all three values with a single write */ + pci_write_config_dword(dev, PCI_PRIMARY_BUS, buses); + + if (!is_cardbus) { + child->bridge_ctl = bctl; + max = pci_scan_child_bus_extend(child, available_buses); + } else { + + /* + * For CardBus bridges, we leave 4 bus numbers as + * cards with a PCI-to-PCI bridge can be inserted + * later. + */ + for (i = 0; i < CARDBUS_RESERVE_BUSNR; i++) { + struct pci_bus *parent = bus; + if (pci_find_bus(pci_domain_nr(bus), + max+i+1)) + break; + while (parent->parent) { + if ((!pcibios_assign_all_busses()) && + (parent->busn_res.end > max) && + (parent->busn_res.end <= max+i)) { + j = 1; + } + parent = parent->parent; + } + if (j) { + + /* + * Often, there are two CardBus + * bridges -- try to leave one + * valid bus number for each one. + */ + i /= 2; + break; + } + } + max += i; + } + + /* + * Set subordinate bus number to its real value. + * If fixed subordinate bus number exists from EA + * capability then use it. + */ + if (fixed_buses) + max = fixed_sub; + pci_bus_update_busn_res_end(child, max); + pci_write_config_byte(dev, PCI_SUBORDINATE_BUS, max); + } + + sprintf(child->name, + (is_cardbus ? "PCI CardBus %04x:%02x" : "PCI Bus %04x:%02x"), + pci_domain_nr(bus), child->number); + + /* Check that all devices are accessible */ + while (bus->parent) { + if ((child->busn_res.end > bus->busn_res.end) || + (child->number > bus->busn_res.end) || + (child->number < bus->number) || + (child->busn_res.end < bus->number)) { + dev_info(&dev->dev, "devices behind bridge are unusable because %pR cannot be assigned for them\n", + &child->busn_res); + break; + } + bus = bus->parent; + } + +out: + pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl); + + pm_runtime_put(&dev->dev); + + return max; +} + +/* + * pci_scan_bridge() - Scan buses behind a bridge + * @bus: Parent bus the bridge is on + * @dev: Bridge itself + * @max: Starting subordinate number of buses behind this bridge + * @pass: Either %0 (scan already configured bridges) or %1 (scan bridges + * that need to be reconfigured. + * + * If it's a bridge, configure it and scan the bus behind it. + * For CardBus bridges, we don't scan behind as the devices will + * be handled by the bridge driver itself. + * + * We need to process bridges in two passes -- first we scan those + * already configured by the BIOS and after we are done with all of + * them, we proceed to assigning numbers to the remaining buses in + * order to avoid overlaps between old and new bus numbers. + * + * Return: New subordinate number covering all buses behind this bridge. + */ +int pci_scan_bridge(struct pci_bus *bus, struct pci_dev *dev, int max, int pass) +{ + return pci_scan_bridge_extend(bus, dev, max, 0, pass); +} +EXPORT_SYMBOL(pci_scan_bridge); + +/* + * Read interrupt line and base address registers. + * The architecture-dependent code can tweak these, of course. + */ +static void pci_read_irq(struct pci_dev *dev) +{ + unsigned char irq; + + /* VFs are not allowed to use INTx, so skip the config reads */ + if (dev->is_virtfn) { + dev->pin = 0; + dev->irq = 0; + return; + } + + pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &irq); + dev->pin = irq; + if (irq) + pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &irq); + dev->irq = irq; +} + +void set_pcie_port_type(struct pci_dev *pdev) +{ + int pos; + u16 reg16; + u32 reg32; + int type; + struct pci_dev *parent; + + pos = pci_find_capability(pdev, PCI_CAP_ID_EXP); + if (!pos) + return; + + pdev->pcie_cap = pos; + pci_read_config_word(pdev, pos + PCI_EXP_FLAGS, ®16); + pdev->pcie_flags_reg = reg16; + pci_read_config_dword(pdev, pos + PCI_EXP_DEVCAP, &pdev->devcap); + pdev->pcie_mpss = FIELD_GET(PCI_EXP_DEVCAP_PAYLOAD, pdev->devcap); + + pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, ®32); + if (reg32 & PCI_EXP_LNKCAP_DLLLARC) + pdev->link_active_reporting = 1; + + parent = pci_upstream_bridge(pdev); + if (!parent) + return; + + /* + * Some systems do not identify their upstream/downstream ports + * correctly so detect impossible configurations here and correct + * the port type accordingly. + */ + type = pci_pcie_type(pdev); + if (type == PCI_EXP_TYPE_DOWNSTREAM) { + /* + * If pdev claims to be downstream port but the parent + * device is also downstream port assume pdev is actually + * upstream port. + */ + if (pcie_downstream_port(parent)) { + pci_info(pdev, "claims to be downstream port but is acting as upstream port, correcting type\n"); + pdev->pcie_flags_reg &= ~PCI_EXP_FLAGS_TYPE; + pdev->pcie_flags_reg |= PCI_EXP_TYPE_UPSTREAM; + } + } else if (type == PCI_EXP_TYPE_UPSTREAM) { + /* + * If pdev claims to be upstream port but the parent + * device is also upstream port assume pdev is actually + * downstream port. + */ + if (pci_pcie_type(parent) == PCI_EXP_TYPE_UPSTREAM) { + pci_info(pdev, "claims to be upstream port but is acting as downstream port, correcting type\n"); + pdev->pcie_flags_reg &= ~PCI_EXP_FLAGS_TYPE; + pdev->pcie_flags_reg |= PCI_EXP_TYPE_DOWNSTREAM; + } + } +} + +void set_pcie_hotplug_bridge(struct pci_dev *pdev) +{ + u32 reg32; + + pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, ®32); + if (reg32 & PCI_EXP_SLTCAP_HPC) + pdev->is_hotplug_bridge = 1; +} + +static void set_pcie_thunderbolt(struct pci_dev *dev) +{ + u16 vsec; + + /* Is the device part of a Thunderbolt controller? */ + vsec = pci_find_vsec_capability(dev, PCI_VENDOR_ID_INTEL, PCI_VSEC_ID_INTEL_TBT); + if (vsec) + dev->is_thunderbolt = 1; +} + +static void set_pcie_untrusted(struct pci_dev *dev) +{ + struct pci_dev *parent; + + /* + * If the upstream bridge is untrusted we treat this device + * untrusted as well. + */ + parent = pci_upstream_bridge(dev); + if (parent && (parent->untrusted || parent->external_facing)) + dev->untrusted = true; +} + +static void pci_set_removable(struct pci_dev *dev) +{ + struct pci_dev *parent = pci_upstream_bridge(dev); + + /* + * We (only) consider everything downstream from an external_facing + * device to be removable by the user. We're mainly concerned with + * consumer platforms with user accessible thunderbolt ports that are + * vulnerable to DMA attacks, and we expect those ports to be marked by + * the firmware as external_facing. Devices in traditional hotplug + * slots can technically be removed, but the expectation is that unless + * the port is marked with external_facing, such devices are less + * accessible to user / may not be removed by end user, and thus not + * exposed as "removable" to userspace. + */ + if (parent && + (parent->external_facing || dev_is_removable(&parent->dev))) + dev_set_removable(&dev->dev, DEVICE_REMOVABLE); +} + +/** + * pci_ext_cfg_is_aliased - Is ext config space just an alias of std config? + * @dev: PCI device + * + * PCI Express to PCI/PCI-X Bridge Specification, rev 1.0, 4.1.4 says that + * when forwarding a type1 configuration request the bridge must check that + * the extended register address field is zero. The bridge is not permitted + * to forward the transactions and must handle it as an Unsupported Request. + * Some bridges do not follow this rule and simply drop the extended register + * bits, resulting in the standard config space being aliased, every 256 + * bytes across the entire configuration space. Test for this condition by + * comparing the first dword of each potential alias to the vendor/device ID. + * Known offenders: + * ASM1083/1085 PCIe-to-PCI Reversible Bridge (1b21:1080, rev 01 & 03) + * AMD/ATI SBx00 PCI to PCI Bridge (1002:4384, rev 40) + */ +static bool pci_ext_cfg_is_aliased(struct pci_dev *dev) +{ +#ifdef CONFIG_PCI_QUIRKS + int pos, ret; + u32 header, tmp; + + pci_read_config_dword(dev, PCI_VENDOR_ID, &header); + + for (pos = PCI_CFG_SPACE_SIZE; + pos < PCI_CFG_SPACE_EXP_SIZE; pos += PCI_CFG_SPACE_SIZE) { + ret = pci_read_config_dword(dev, pos, &tmp); + if ((ret != PCIBIOS_SUCCESSFUL) || (header != tmp)) + return false; + } + + return true; +#else + return false; +#endif +} + +/** + * pci_cfg_space_size_ext - Get the configuration space size of the PCI device + * @dev: PCI device + * + * Regular PCI devices have 256 bytes, but PCI-X 2 and PCI Express devices + * have 4096 bytes. Even if the device is capable, that doesn't mean we can + * access it. Maybe we don't have a way to generate extended config space + * accesses, or the device is behind a reverse Express bridge. So we try + * reading the dword at 0x100 which must either be 0 or a valid extended + * capability header. + */ +static int pci_cfg_space_size_ext(struct pci_dev *dev) +{ + u32 status; + int pos = PCI_CFG_SPACE_SIZE; + + if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL) + return PCI_CFG_SPACE_SIZE; + if (PCI_POSSIBLE_ERROR(status) || pci_ext_cfg_is_aliased(dev)) + return PCI_CFG_SPACE_SIZE; + + return PCI_CFG_SPACE_EXP_SIZE; +} + +int pci_cfg_space_size(struct pci_dev *dev) +{ + int pos; + u32 status; + u16 class; + +#ifdef CONFIG_PCI_IOV + /* + * Per the SR-IOV specification (rev 1.1, sec 3.5), VFs are required to + * implement a PCIe capability and therefore must implement extended + * config space. We can skip the NO_EXTCFG test below and the + * reachability/aliasing test in pci_cfg_space_size_ext() by virtue of + * the fact that the SR-IOV capability on the PF resides in extended + * config space and must be accessible and non-aliased to have enabled + * support for this VF. This is a micro performance optimization for + * systems supporting many VFs. + */ + if (dev->is_virtfn) + return PCI_CFG_SPACE_EXP_SIZE; +#endif + + if (dev->bus->bus_flags & PCI_BUS_FLAGS_NO_EXTCFG) + return PCI_CFG_SPACE_SIZE; + + class = dev->class >> 8; + if (class == PCI_CLASS_BRIDGE_HOST) + return pci_cfg_space_size_ext(dev); + + if (pci_is_pcie(dev)) + return pci_cfg_space_size_ext(dev); + + pos = pci_find_capability(dev, PCI_CAP_ID_PCIX); + if (!pos) + return PCI_CFG_SPACE_SIZE; + + pci_read_config_dword(dev, pos + PCI_X_STATUS, &status); + if (status & (PCI_X_STATUS_266MHZ | PCI_X_STATUS_533MHZ)) + return pci_cfg_space_size_ext(dev); + + return PCI_CFG_SPACE_SIZE; +} + +static u32 pci_class(struct pci_dev *dev) +{ + u32 class; + +#ifdef CONFIG_PCI_IOV + if (dev->is_virtfn) + return dev->physfn->sriov->class; +#endif + pci_read_config_dword(dev, PCI_CLASS_REVISION, &class); + return class; +} + +static void pci_subsystem_ids(struct pci_dev *dev, u16 *vendor, u16 *device) +{ +#ifdef CONFIG_PCI_IOV + if (dev->is_virtfn) { + *vendor = dev->physfn->sriov->subsystem_vendor; + *device = dev->physfn->sriov->subsystem_device; + return; + } +#endif + pci_read_config_word(dev, PCI_SUBSYSTEM_VENDOR_ID, vendor); + pci_read_config_word(dev, PCI_SUBSYSTEM_ID, device); +} + +static u8 pci_hdr_type(struct pci_dev *dev) +{ + u8 hdr_type; + +#ifdef CONFIG_PCI_IOV + if (dev->is_virtfn) + return dev->physfn->sriov->hdr_type; +#endif + pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type); + return hdr_type; +} + +#define LEGACY_IO_RESOURCE (IORESOURCE_IO | IORESOURCE_PCI_FIXED) + +/** + * pci_intx_mask_broken - Test PCI_COMMAND_INTX_DISABLE writability + * @dev: PCI device + * + * Test whether PCI_COMMAND_INTX_DISABLE is writable for @dev. Check this + * at enumeration-time to avoid modifying PCI_COMMAND at run-time. + */ +static int pci_intx_mask_broken(struct pci_dev *dev) +{ + u16 orig, toggle, new; + + pci_read_config_word(dev, PCI_COMMAND, &orig); + toggle = orig ^ PCI_COMMAND_INTX_DISABLE; + pci_write_config_word(dev, PCI_COMMAND, toggle); + pci_read_config_word(dev, PCI_COMMAND, &new); + + pci_write_config_word(dev, PCI_COMMAND, orig); + + /* + * PCI_COMMAND_INTX_DISABLE was reserved and read-only prior to PCI + * r2.3, so strictly speaking, a device is not *broken* if it's not + * writable. But we'll live with the misnomer for now. + */ + if (new != toggle) + return 1; + return 0; +} + +static void early_dump_pci_device(struct pci_dev *pdev) +{ + u32 value[256 / 4]; + int i; + + pci_info(pdev, "config space:\n"); + + for (i = 0; i < 256; i += 4) + pci_read_config_dword(pdev, i, &value[i / 4]); + + print_hex_dump(KERN_INFO, "", DUMP_PREFIX_OFFSET, 16, 1, + value, 256, false); +} + +/** + * pci_setup_device - Fill in class and map information of a device + * @dev: the device structure to fill + * + * Initialize the device structure with information about the device's + * vendor,class,memory and IO-space addresses, IRQ lines etc. + * Called at initialisation of the PCI subsystem and by CardBus services. + * Returns 0 on success and negative if unknown type of device (not normal, + * bridge or CardBus). + */ +int pci_setup_device(struct pci_dev *dev) +{ + u32 class; + u16 cmd; + u8 hdr_type; + int err, pos = 0; + struct pci_bus_region region; + struct resource *res; + + hdr_type = pci_hdr_type(dev); + + dev->sysdata = dev->bus->sysdata; + dev->dev.parent = dev->bus->bridge; + dev->dev.bus = &pci_bus_type; + dev->hdr_type = hdr_type & 0x7f; + dev->multifunction = !!(hdr_type & 0x80); + dev->error_state = pci_channel_io_normal; + set_pcie_port_type(dev); + + err = pci_set_of_node(dev); + if (err) + return err; + pci_set_acpi_fwnode(dev); + + pci_dev_assign_slot(dev); + + /* + * Assume 32-bit PCI; let 64-bit PCI cards (which are far rarer) + * set this higher, assuming the system even supports it. + */ + dev->dma_mask = 0xffffffff; + + dev_set_name(&dev->dev, "%04x:%02x:%02x.%d", pci_domain_nr(dev->bus), + dev->bus->number, PCI_SLOT(dev->devfn), + PCI_FUNC(dev->devfn)); + + class = pci_class(dev); + + dev->revision = class & 0xff; + dev->class = class >> 8; /* upper 3 bytes */ + + if (pci_early_dump) + early_dump_pci_device(dev); + + /* Need to have dev->class ready */ + dev->cfg_size = pci_cfg_space_size(dev); + + /* Need to have dev->cfg_size ready */ + set_pcie_thunderbolt(dev); + + set_pcie_untrusted(dev); + + /* "Unknown power state" */ + dev->current_state = PCI_UNKNOWN; + + /* Early fixups, before probing the BARs */ + pci_fixup_device(pci_fixup_early, dev); + + pci_set_removable(dev); + + pci_info(dev, "[%04x:%04x] type %02x class %#08x\n", + dev->vendor, dev->device, dev->hdr_type, dev->class); + + /* Device class may be changed after fixup */ + class = dev->class >> 8; + + if (dev->non_compliant_bars && !dev->mmio_always_on) { + pci_read_config_word(dev, PCI_COMMAND, &cmd); + if (cmd & (PCI_COMMAND_IO | PCI_COMMAND_MEMORY)) { + pci_info(dev, "device has non-compliant BARs; disabling IO/MEM decoding\n"); + cmd &= ~PCI_COMMAND_IO; + cmd &= ~PCI_COMMAND_MEMORY; + pci_write_config_word(dev, PCI_COMMAND, cmd); + } + } + + dev->broken_intx_masking = pci_intx_mask_broken(dev); + + switch (dev->hdr_type) { /* header type */ + case PCI_HEADER_TYPE_NORMAL: /* standard header */ + if (class == PCI_CLASS_BRIDGE_PCI) + goto bad; + pci_read_irq(dev); + pci_read_bases(dev, 6, PCI_ROM_ADDRESS); + + pci_subsystem_ids(dev, &dev->subsystem_vendor, &dev->subsystem_device); + + /* + * Do the ugly legacy mode stuff here rather than broken chip + * quirk code. Legacy mode ATA controllers have fixed + * addresses. These are not always echoed in BAR0-3, and + * BAR0-3 in a few cases contain junk! + */ + if (class == PCI_CLASS_STORAGE_IDE) { + u8 progif; + pci_read_config_byte(dev, PCI_CLASS_PROG, &progif); + if ((progif & 1) == 0) { + region.start = 0x1F0; + region.end = 0x1F7; + res = &dev->resource[0]; + res->flags = LEGACY_IO_RESOURCE; + pcibios_bus_to_resource(dev->bus, res, ®ion); + pci_info(dev, "legacy IDE quirk: reg 0x10: %pR\n", + res); + region.start = 0x3F6; + region.end = 0x3F6; + res = &dev->resource[1]; + res->flags = LEGACY_IO_RESOURCE; + pcibios_bus_to_resource(dev->bus, res, ®ion); + pci_info(dev, "legacy IDE quirk: reg 0x14: %pR\n", + res); + } + if ((progif & 4) == 0) { + region.start = 0x170; + region.end = 0x177; + res = &dev->resource[2]; + res->flags = LEGACY_IO_RESOURCE; + pcibios_bus_to_resource(dev->bus, res, ®ion); + pci_info(dev, "legacy IDE quirk: reg 0x18: %pR\n", + res); + region.start = 0x376; + region.end = 0x376; + res = &dev->resource[3]; + res->flags = LEGACY_IO_RESOURCE; + pcibios_bus_to_resource(dev->bus, res, ®ion); + pci_info(dev, "legacy IDE quirk: reg 0x1c: %pR\n", + res); + } + } + break; + + case PCI_HEADER_TYPE_BRIDGE: /* bridge header */ + /* + * The PCI-to-PCI bridge spec requires that subtractive + * decoding (i.e. transparent) bridge must have programming + * interface code of 0x01. + */ + pci_read_irq(dev); + dev->transparent = ((dev->class & 0xff) == 1); + pci_read_bases(dev, 2, PCI_ROM_ADDRESS1); + pci_read_bridge_windows(dev); + set_pcie_hotplug_bridge(dev); + pos = pci_find_capability(dev, PCI_CAP_ID_SSVID); + if (pos) { + pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor); + pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device); + } + break; + + case PCI_HEADER_TYPE_CARDBUS: /* CardBus bridge header */ + if (class != PCI_CLASS_BRIDGE_CARDBUS) + goto bad; + pci_read_irq(dev); + pci_read_bases(dev, 1, 0); + pci_read_config_word(dev, PCI_CB_SUBSYSTEM_VENDOR_ID, &dev->subsystem_vendor); + pci_read_config_word(dev, PCI_CB_SUBSYSTEM_ID, &dev->subsystem_device); + break; + + default: /* unknown header */ + pci_err(dev, "unknown header type %02x, ignoring device\n", + dev->hdr_type); + pci_release_of_node(dev); + return -EIO; + + bad: + pci_err(dev, "ignoring class %#08x (doesn't match header type %02x)\n", + dev->class, dev->hdr_type); + dev->class = PCI_CLASS_NOT_DEFINED << 8; + } + + /* We found a fine healthy device, go go go... */ + return 0; +} + +static void pci_configure_mps(struct pci_dev *dev) +{ + struct pci_dev *bridge = pci_upstream_bridge(dev); + int mps, mpss, p_mps, rc; + + if (!pci_is_pcie(dev)) + return; + + /* MPS and MRRS fields are of type 'RsvdP' for VFs, short-circuit out */ + if (dev->is_virtfn) + return; + + /* + * For Root Complex Integrated Endpoints, program the maximum + * supported value unless limited by the PCIE_BUS_PEER2PEER case. + */ + if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) { + if (pcie_bus_config == PCIE_BUS_PEER2PEER) + mps = 128; + else + mps = 128 << dev->pcie_mpss; + rc = pcie_set_mps(dev, mps); + if (rc) { + pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n", + mps); + } + return; + } + + if (!bridge || !pci_is_pcie(bridge)) + return; + + mps = pcie_get_mps(dev); + p_mps = pcie_get_mps(bridge); + + if (mps == p_mps) + return; + + if (pcie_bus_config == PCIE_BUS_TUNE_OFF) { + pci_warn(dev, "Max Payload Size %d, but upstream %s set to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n", + mps, pci_name(bridge), p_mps); + return; + } + + /* + * Fancier MPS configuration is done later by + * pcie_bus_configure_settings() + */ + if (pcie_bus_config != PCIE_BUS_DEFAULT) + return; + + mpss = 128 << dev->pcie_mpss; + if (mpss < p_mps && pci_pcie_type(bridge) == PCI_EXP_TYPE_ROOT_PORT) { + pcie_set_mps(bridge, mpss); + pci_info(dev, "Upstream bridge's Max Payload Size set to %d (was %d, max %d)\n", + mpss, p_mps, 128 << bridge->pcie_mpss); + p_mps = pcie_get_mps(bridge); + } + + rc = pcie_set_mps(dev, p_mps); + if (rc) { + pci_warn(dev, "can't set Max Payload Size to %d; if necessary, use \"pci=pcie_bus_safe\" and report a bug\n", + p_mps); + return; + } + + pci_info(dev, "Max Payload Size set to %d (was %d, max %d)\n", + p_mps, mps, mpss); +} + +int pci_configure_extended_tags(struct pci_dev *dev, void *ign) +{ + struct pci_host_bridge *host; + u32 cap; + u16 ctl; + int ret; + + if (!pci_is_pcie(dev)) + return 0; + + ret = pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap); + if (ret) + return 0; + + if (!(cap & PCI_EXP_DEVCAP_EXT_TAG)) + return 0; + + ret = pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &ctl); + if (ret) + return 0; + + host = pci_find_host_bridge(dev->bus); + if (!host) + return 0; + + /* + * If some device in the hierarchy doesn't handle Extended Tags + * correctly, make sure they're disabled. + */ + if (host->no_ext_tags) { + if (ctl & PCI_EXP_DEVCTL_EXT_TAG) { + pci_info(dev, "disabling Extended Tags\n"); + pcie_capability_clear_word(dev, PCI_EXP_DEVCTL, + PCI_EXP_DEVCTL_EXT_TAG); + } + return 0; + } + + if (!(ctl & PCI_EXP_DEVCTL_EXT_TAG)) { + pci_info(dev, "enabling Extended Tags\n"); + pcie_capability_set_word(dev, PCI_EXP_DEVCTL, + PCI_EXP_DEVCTL_EXT_TAG); + } + return 0; +} + +/** + * pcie_relaxed_ordering_enabled - Probe for PCIe relaxed ordering enable + * @dev: PCI device to query + * + * Returns true if the device has enabled relaxed ordering attribute. + */ +bool pcie_relaxed_ordering_enabled(struct pci_dev *dev) +{ + u16 v; + + pcie_capability_read_word(dev, PCI_EXP_DEVCTL, &v); + + return !!(v & PCI_EXP_DEVCTL_RELAX_EN); +} +EXPORT_SYMBOL(pcie_relaxed_ordering_enabled); + +static void pci_configure_relaxed_ordering(struct pci_dev *dev) +{ + struct pci_dev *root; + + /* PCI_EXP_DEVCTL_RELAX_EN is RsvdP in VFs */ + if (dev->is_virtfn) + return; + + if (!pcie_relaxed_ordering_enabled(dev)) + return; + + /* + * For now, we only deal with Relaxed Ordering issues with Root + * Ports. Peer-to-Peer DMA is another can of worms. + */ + root = pcie_find_root_port(dev); + if (!root) + return; + + if (root->dev_flags & PCI_DEV_FLAGS_NO_RELAXED_ORDERING) { + pcie_capability_clear_word(dev, PCI_EXP_DEVCTL, + PCI_EXP_DEVCTL_RELAX_EN); + pci_info(dev, "Relaxed Ordering disabled because the Root Port didn't support it\n"); + } +} + +static void pci_configure_ltr(struct pci_dev *dev) +{ +#ifdef CONFIG_PCIEASPM + struct pci_host_bridge *host = pci_find_host_bridge(dev->bus); + struct pci_dev *bridge; + u32 cap, ctl; + + if (!pci_is_pcie(dev)) + return; + + /* Read L1 PM substate capabilities */ + dev->l1ss = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_L1SS); + + pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap); + if (!(cap & PCI_EXP_DEVCAP2_LTR)) + return; + + pcie_capability_read_dword(dev, PCI_EXP_DEVCTL2, &ctl); + if (ctl & PCI_EXP_DEVCTL2_LTR_EN) { + if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) { + dev->ltr_path = 1; + return; + } + + bridge = pci_upstream_bridge(dev); + if (bridge && bridge->ltr_path) + dev->ltr_path = 1; + + return; + } + + if (!host->native_ltr) + return; + + /* + * Software must not enable LTR in an Endpoint unless the Root + * Complex and all intermediate Switches indicate support for LTR. + * PCIe r4.0, sec 6.18. + */ + if (pci_pcie_type(dev) == PCI_EXP_TYPE_ROOT_PORT) { + pcie_capability_set_word(dev, PCI_EXP_DEVCTL2, + PCI_EXP_DEVCTL2_LTR_EN); + dev->ltr_path = 1; + return; + } + + /* + * If we're configuring a hot-added device, LTR was likely + * disabled in the upstream bridge, so re-enable it before enabling + * it in the new device. + */ + bridge = pci_upstream_bridge(dev); + if (bridge && bridge->ltr_path) { + pci_bridge_reconfigure_ltr(dev); + pcie_capability_set_word(dev, PCI_EXP_DEVCTL2, + PCI_EXP_DEVCTL2_LTR_EN); + dev->ltr_path = 1; + } +#endif +} + +static void pci_configure_eetlp_prefix(struct pci_dev *dev) +{ +#ifdef CONFIG_PCI_PASID + struct pci_dev *bridge; + int pcie_type; + u32 cap; + + if (!pci_is_pcie(dev)) + return; + + pcie_capability_read_dword(dev, PCI_EXP_DEVCAP2, &cap); + if (!(cap & PCI_EXP_DEVCAP2_EE_PREFIX)) + return; + + pcie_type = pci_pcie_type(dev); + if (pcie_type == PCI_EXP_TYPE_ROOT_PORT || + pcie_type == PCI_EXP_TYPE_RC_END) + dev->eetlp_prefix_path = 1; + else { + bridge = pci_upstream_bridge(dev); + if (bridge && bridge->eetlp_prefix_path) + dev->eetlp_prefix_path = 1; + } +#endif +} + +static void pci_configure_serr(struct pci_dev *dev) +{ + u16 control; + + if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) { + + /* + * A bridge will not forward ERR_ messages coming from an + * endpoint unless SERR# forwarding is enabled. + */ + pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &control); + if (!(control & PCI_BRIDGE_CTL_SERR)) { + control |= PCI_BRIDGE_CTL_SERR; + pci_write_config_word(dev, PCI_BRIDGE_CONTROL, control); + } + } +} + +static void pci_configure_device(struct pci_dev *dev) +{ + pci_configure_mps(dev); + pci_configure_extended_tags(dev, NULL); + pci_configure_relaxed_ordering(dev); + pci_configure_ltr(dev); + pci_configure_eetlp_prefix(dev); + pci_configure_serr(dev); + + pci_acpi_program_hp_params(dev); +} + +static void pci_release_capabilities(struct pci_dev *dev) +{ + pci_aer_exit(dev); + pci_rcec_exit(dev); + pci_iov_release(dev); + pci_free_cap_save_buffers(dev); +} + +/** + * pci_release_dev - Free a PCI device structure when all users of it are + * finished + * @dev: device that's been disconnected + * + * Will be called only by the device core when all users of this PCI device are + * done. + */ +static void pci_release_dev(struct device *dev) +{ + struct pci_dev *pci_dev; + + pci_dev = to_pci_dev(dev); + pci_release_capabilities(pci_dev); + pci_release_of_node(pci_dev); + pcibios_release_device(pci_dev); + pci_bus_put(pci_dev->bus); + kfree(pci_dev->driver_override); + bitmap_free(pci_dev->dma_alias_mask); + dev_dbg(dev, "device released\n"); + kfree(pci_dev); +} + +struct pci_dev *pci_alloc_dev(struct pci_bus *bus) +{ + struct pci_dev *dev; + + dev = kzalloc(sizeof(struct pci_dev), GFP_KERNEL); + if (!dev) + return NULL; + + INIT_LIST_HEAD(&dev->bus_list); + dev->dev.type = &pci_dev_type; + dev->bus = pci_bus_get(bus); + dev->driver_exclusive_resource = (struct resource) { + .name = "PCI Exclusive", + .start = 0, + .end = -1, + }; + + spin_lock_init(&dev->pcie_cap_lock); +#ifdef CONFIG_PCI_MSI + raw_spin_lock_init(&dev->msi_lock); +#endif + return dev; +} +EXPORT_SYMBOL(pci_alloc_dev); + +static bool pci_bus_crs_vendor_id(u32 l) +{ + return (l & 0xffff) == PCI_VENDOR_ID_PCI_SIG; +} + +static bool pci_bus_wait_crs(struct pci_bus *bus, int devfn, u32 *l, + int timeout) +{ + int delay = 1; + + if (!pci_bus_crs_vendor_id(*l)) + return true; /* not a CRS completion */ + + if (!timeout) + return false; /* CRS, but caller doesn't want to wait */ + + /* + * We got the reserved Vendor ID that indicates a completion with + * Configuration Request Retry Status (CRS). Retry until we get a + * valid Vendor ID or we time out. + */ + while (pci_bus_crs_vendor_id(*l)) { + if (delay > timeout) { + pr_warn("pci %04x:%02x:%02x.%d: not ready after %dms; giving up\n", + pci_domain_nr(bus), bus->number, + PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1); + + return false; + } + if (delay >= 1000) + pr_info("pci %04x:%02x:%02x.%d: not ready after %dms; waiting\n", + pci_domain_nr(bus), bus->number, + PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1); + + msleep(delay); + delay *= 2; + + if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l)) + return false; + } + + if (delay >= 1000) + pr_info("pci %04x:%02x:%02x.%d: ready after %dms\n", + pci_domain_nr(bus), bus->number, + PCI_SLOT(devfn), PCI_FUNC(devfn), delay - 1); + + return true; +} + +bool pci_bus_generic_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l, + int timeout) +{ + if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l)) + return false; + + /* Some broken boards return 0 or ~0 (PCI_ERROR_RESPONSE) if a slot is empty: */ + if (PCI_POSSIBLE_ERROR(*l) || *l == 0x00000000 || + *l == 0x0000ffff || *l == 0xffff0000) + return false; + + if (pci_bus_crs_vendor_id(*l)) + return pci_bus_wait_crs(bus, devfn, l, timeout); + + return true; +} + +bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l, + int timeout) +{ +#ifdef CONFIG_PCI_QUIRKS + struct pci_dev *bridge = bus->self; + + /* + * Certain IDT switches have an issue where they improperly trigger + * ACS Source Validation errors on completions for config reads. + */ + if (bridge && bridge->vendor == PCI_VENDOR_ID_IDT && + bridge->device == 0x80b5) + return pci_idt_bus_quirk(bus, devfn, l, timeout); +#endif + + return pci_bus_generic_read_dev_vendor_id(bus, devfn, l, timeout); +} +EXPORT_SYMBOL(pci_bus_read_dev_vendor_id); + +/* + * Read the config data for a PCI device, sanity-check it, + * and fill in the dev structure. + */ +static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn) +{ + struct pci_dev *dev; + u32 l; + + if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000)) + return NULL; + + dev = pci_alloc_dev(bus); + if (!dev) + return NULL; + + dev->devfn = devfn; + dev->vendor = l & 0xffff; + dev->device = (l >> 16) & 0xffff; + + if (pci_setup_device(dev)) { + pci_bus_put(dev->bus); + kfree(dev); + return NULL; + } + + return dev; +} + +void pcie_report_downtraining(struct pci_dev *dev) +{ + if (!pci_is_pcie(dev)) + return; + + /* Look from the device up to avoid downstream ports with no devices */ + if ((pci_pcie_type(dev) != PCI_EXP_TYPE_ENDPOINT) && + (pci_pcie_type(dev) != PCI_EXP_TYPE_LEG_END) && + (pci_pcie_type(dev) != PCI_EXP_TYPE_UPSTREAM)) + return; + + /* Multi-function PCIe devices share the same link/status */ + if (PCI_FUNC(dev->devfn) != 0 || dev->is_virtfn) + return; + + /* Print link status only if the device is constrained by the fabric */ + __pcie_print_link_status(dev, false); +} + +static void pci_init_capabilities(struct pci_dev *dev) +{ + pci_ea_init(dev); /* Enhanced Allocation */ + pci_msi_init(dev); /* Disable MSI */ + pci_msix_init(dev); /* Disable MSI-X */ + + /* Buffers for saving PCIe and PCI-X capabilities */ + pci_allocate_cap_save_buffers(dev); + + pci_pm_init(dev); /* Power Management */ + pci_vpd_init(dev); /* Vital Product Data */ + pci_configure_ari(dev); /* Alternative Routing-ID Forwarding */ + pci_iov_init(dev); /* Single Root I/O Virtualization */ + pci_ats_init(dev); /* Address Translation Services */ + pci_pri_init(dev); /* Page Request Interface */ + pci_pasid_init(dev); /* Process Address Space ID */ + pci_acs_init(dev); /* Access Control Services */ + pci_ptm_init(dev); /* Precision Time Measurement */ + pci_aer_init(dev); /* Advanced Error Reporting */ + pci_dpc_init(dev); /* Downstream Port Containment */ + pci_rcec_init(dev); /* Root Complex Event Collector */ + pci_doe_init(dev); /* Data Object Exchange */ + + pcie_report_downtraining(dev); + pci_init_reset_methods(dev); +} + +/* + * This is the equivalent of pci_host_bridge_msi_domain() that acts on + * devices. Firmware interfaces that can select the MSI domain on a + * per-device basis should be called from here. + */ +static struct irq_domain *pci_dev_msi_domain(struct pci_dev *dev) +{ + struct irq_domain *d; + + /* + * If a domain has been set through the pcibios_device_add() + * callback, then this is the one (platform code knows best). + */ + d = dev_get_msi_domain(&dev->dev); + if (d) + return d; + + /* + * Let's see if we have a firmware interface able to provide + * the domain. + */ + d = pci_msi_get_device_domain(dev); + if (d) + return d; + + return NULL; +} + +static void pci_set_msi_domain(struct pci_dev *dev) +{ + struct irq_domain *d; + + /* + * If the platform or firmware interfaces cannot supply a + * device-specific MSI domain, then inherit the default domain + * from the host bridge itself. + */ + d = pci_dev_msi_domain(dev); + if (!d) + d = dev_get_msi_domain(&dev->bus->dev); + + dev_set_msi_domain(&dev->dev, d); +} + +void pci_device_add(struct pci_dev *dev, struct pci_bus *bus) +{ + int ret; + + pci_configure_device(dev); + + device_initialize(&dev->dev); + dev->dev.release = pci_release_dev; + + set_dev_node(&dev->dev, pcibus_to_node(bus)); + dev->dev.dma_mask = &dev->dma_mask; + dev->dev.dma_parms = &dev->dma_parms; + dev->dev.coherent_dma_mask = 0xffffffffull; + + dma_set_max_seg_size(&dev->dev, 65536); + dma_set_seg_boundary(&dev->dev, 0xffffffff); + + pcie_failed_link_retrain(dev); + + /* Fix up broken headers */ + pci_fixup_device(pci_fixup_header, dev); + + pci_reassigndev_resource_alignment(dev); + + dev->state_saved = false; + + pci_init_capabilities(dev); + + /* + * Add the device to our list of discovered devices + * and the bus list for fixup functions, etc. + */ + down_write(&pci_bus_sem); + list_add_tail(&dev->bus_list, &bus->devices); + up_write(&pci_bus_sem); + + ret = pcibios_device_add(dev); + WARN_ON(ret < 0); + + /* Set up MSI IRQ domain */ + pci_set_msi_domain(dev); + + /* Notifier could use PCI capabilities */ + dev->match_driver = false; + ret = device_add(&dev->dev); + WARN_ON(ret < 0); +} + +struct pci_dev *pci_scan_single_device(struct pci_bus *bus, int devfn) +{ + struct pci_dev *dev; + + dev = pci_get_slot(bus, devfn); + if (dev) { + pci_dev_put(dev); + return dev; + } + + dev = pci_scan_device(bus, devfn); + if (!dev) + return NULL; + + pci_device_add(dev, bus); + + return dev; +} +EXPORT_SYMBOL(pci_scan_single_device); + +static int next_ari_fn(struct pci_bus *bus, struct pci_dev *dev, int fn) +{ + int pos; + u16 cap = 0; + unsigned int next_fn; + + if (!dev) + return -ENODEV; + + pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI); + if (!pos) + return -ENODEV; + + pci_read_config_word(dev, pos + PCI_ARI_CAP, &cap); + next_fn = PCI_ARI_CAP_NFN(cap); + if (next_fn <= fn) + return -ENODEV; /* protect against malformed list */ + + return next_fn; +} + +static int next_fn(struct pci_bus *bus, struct pci_dev *dev, int fn) +{ + if (pci_ari_enabled(bus)) + return next_ari_fn(bus, dev, fn); + + if (fn >= 7) + return -ENODEV; + /* only multifunction devices may have more functions */ + if (dev && !dev->multifunction) + return -ENODEV; + + return fn + 1; +} + +static int only_one_child(struct pci_bus *bus) +{ + struct pci_dev *bridge = bus->self; + + /* + * Systems with unusual topologies set PCI_SCAN_ALL_PCIE_DEVS so + * we scan for all possible devices, not just Device 0. + */ + if (pci_has_flag(PCI_SCAN_ALL_PCIE_DEVS)) + return 0; + + /* + * A PCIe Downstream Port normally leads to a Link with only Device + * 0 on it (PCIe spec r3.1, sec 7.3.1). As an optimization, scan + * only for Device 0 in that situation. + */ + if (bridge && pci_is_pcie(bridge) && pcie_downstream_port(bridge)) + return 1; + + return 0; +} + +/** + * pci_scan_slot - Scan a PCI slot on a bus for devices + * @bus: PCI bus to scan + * @devfn: slot number to scan (must have zero function) + * + * Scan a PCI slot on the specified PCI bus for devices, adding + * discovered devices to the @bus->devices list. New devices + * will not have is_added set. + * + * Returns the number of new devices found. + */ +int pci_scan_slot(struct pci_bus *bus, int devfn) +{ + struct pci_dev *dev; + int fn = 0, nr = 0; + + if (only_one_child(bus) && (devfn > 0)) + return 0; /* Already scanned the entire slot */ + + do { + dev = pci_scan_single_device(bus, devfn + fn); + if (dev) { + if (!pci_dev_is_added(dev)) + nr++; + if (fn > 0) + dev->multifunction = 1; + } else if (fn == 0) { + /* + * Function 0 is required unless we are running on + * a hypervisor that passes through individual PCI + * functions. + */ + if (!hypervisor_isolated_pci_functions()) + break; + } + fn = next_fn(bus, dev, fn); + } while (fn >= 0); + + /* Only one slot has PCIe device */ + if (bus->self && nr) + pcie_aspm_init_link_state(bus->self); + + return nr; +} +EXPORT_SYMBOL(pci_scan_slot); + +static int pcie_find_smpss(struct pci_dev *dev, void *data) +{ + u8 *smpss = data; + + if (!pci_is_pcie(dev)) + return 0; + + /* + * We don't have a way to change MPS settings on devices that have + * drivers attached. A hot-added device might support only the minimum + * MPS setting (MPS=128). Therefore, if the fabric contains a bridge + * where devices may be hot-added, we limit the fabric MPS to 128 so + * hot-added devices will work correctly. + * + * However, if we hot-add a device to a slot directly below a Root + * Port, it's impossible for there to be other existing devices below + * the port. We don't limit the MPS in this case because we can + * reconfigure MPS on both the Root Port and the hot-added device, + * and there are no other devices involved. + * + * Note that this PCIE_BUS_SAFE path assumes no peer-to-peer DMA. + */ + if (dev->is_hotplug_bridge && + pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT) + *smpss = 0; + + if (*smpss > dev->pcie_mpss) + *smpss = dev->pcie_mpss; + + return 0; +} + +static void pcie_write_mps(struct pci_dev *dev, int mps) +{ + int rc; + + if (pcie_bus_config == PCIE_BUS_PERFORMANCE) { + mps = 128 << dev->pcie_mpss; + + if (pci_pcie_type(dev) != PCI_EXP_TYPE_ROOT_PORT && + dev->bus->self) + + /* + * For "Performance", the assumption is made that + * downstream communication will never be larger than + * the MRRS. So, the MPS only needs to be configured + * for the upstream communication. This being the case, + * walk from the top down and set the MPS of the child + * to that of the parent bus. + * + * Configure the device MPS with the smaller of the + * device MPSS or the bridge MPS (which is assumed to be + * properly configured at this point to the largest + * allowable MPS based on its parent bus). + */ + mps = min(mps, pcie_get_mps(dev->bus->self)); + } + + rc = pcie_set_mps(dev, mps); + if (rc) + pci_err(dev, "Failed attempting to set the MPS\n"); +} + +static void pcie_write_mrrs(struct pci_dev *dev) +{ + int rc, mrrs; + + /* + * In the "safe" case, do not configure the MRRS. There appear to be + * issues with setting MRRS to 0 on a number of devices. + */ + if (pcie_bus_config != PCIE_BUS_PERFORMANCE) + return; + + /* + * For max performance, the MRRS must be set to the largest supported + * value. However, it cannot be configured larger than the MPS the + * device or the bus can support. This should already be properly + * configured by a prior call to pcie_write_mps(). + */ + mrrs = pcie_get_mps(dev); + + /* + * MRRS is a R/W register. Invalid values can be written, but a + * subsequent read will verify if the value is acceptable or not. + * If the MRRS value provided is not acceptable (e.g., too large), + * shrink the value until it is acceptable to the HW. + */ + while (mrrs != pcie_get_readrq(dev) && mrrs >= 128) { + rc = pcie_set_readrq(dev, mrrs); + if (!rc) + break; + + pci_warn(dev, "Failed attempting to set the MRRS\n"); + mrrs /= 2; + } + + if (mrrs < 128) + pci_err(dev, "MRRS was unable to be configured with a safe value. If problems are experienced, try running with pci=pcie_bus_safe\n"); +} + +static int pcie_bus_configure_set(struct pci_dev *dev, void *data) +{ + int mps, orig_mps; + + if (!pci_is_pcie(dev)) + return 0; + + if (pcie_bus_config == PCIE_BUS_TUNE_OFF || + pcie_bus_config == PCIE_BUS_DEFAULT) + return 0; + + mps = 128 << *(u8 *)data; + orig_mps = pcie_get_mps(dev); + + pcie_write_mps(dev, mps); + pcie_write_mrrs(dev); + + pci_info(dev, "Max Payload Size set to %4d/%4d (was %4d), Max Read Rq %4d\n", + pcie_get_mps(dev), 128 << dev->pcie_mpss, + orig_mps, pcie_get_readrq(dev)); + + return 0; +} + +/* + * pcie_bus_configure_settings() requires that pci_walk_bus work in a top-down, + * parents then children fashion. If this changes, then this code will not + * work as designed. + */ +void pcie_bus_configure_settings(struct pci_bus *bus) +{ + u8 smpss = 0; + + if (!bus->self) + return; + + if (!pci_is_pcie(bus->self)) + return; + + /* + * FIXME - Peer to peer DMA is possible, though the endpoint would need + * to be aware of the MPS of the destination. To work around this, + * simply force the MPS of the entire system to the smallest possible. + */ + if (pcie_bus_config == PCIE_BUS_PEER2PEER) + smpss = 0; + + if (pcie_bus_config == PCIE_BUS_SAFE) { + smpss = bus->self->pcie_mpss; + + pcie_find_smpss(bus->self, &smpss); + pci_walk_bus(bus, pcie_find_smpss, &smpss); + } + + pcie_bus_configure_set(bus->self, &smpss); + pci_walk_bus(bus, pcie_bus_configure_set, &smpss); +} +EXPORT_SYMBOL_GPL(pcie_bus_configure_settings); + +/* + * Called after each bus is probed, but before its children are examined. This + * is marked as __weak because multiple architectures define it. + */ +void __weak pcibios_fixup_bus(struct pci_bus *bus) +{ + /* nothing to do, expected to be removed in the future */ +} + +/** + * pci_scan_child_bus_extend() - Scan devices below a bus + * @bus: Bus to scan for devices + * @available_buses: Total number of buses available (%0 does not try to + * extend beyond the minimal) + * + * Scans devices below @bus including subordinate buses. Returns new + * subordinate number including all the found devices. Passing + * @available_buses causes the remaining bus space to be distributed + * equally between hotplug-capable bridges to allow future extension of the + * hierarchy. + */ +static unsigned int pci_scan_child_bus_extend(struct pci_bus *bus, + unsigned int available_buses) +{ + unsigned int used_buses, normal_bridges = 0, hotplug_bridges = 0; + unsigned int start = bus->busn_res.start; + unsigned int devfn, cmax, max = start; + struct pci_dev *dev; + + dev_dbg(&bus->dev, "scanning bus\n"); + + /* Go find them, Rover! */ + for (devfn = 0; devfn < 256; devfn += 8) + pci_scan_slot(bus, devfn); + + /* Reserve buses for SR-IOV capability */ + used_buses = pci_iov_bus_range(bus); + max += used_buses; + + /* + * After performing arch-dependent fixup of the bus, look behind + * all PCI-to-PCI bridges on this bus. + */ + if (!bus->is_added) { + dev_dbg(&bus->dev, "fixups for bus\n"); + pcibios_fixup_bus(bus); + bus->is_added = 1; + } + + /* + * Calculate how many hotplug bridges and normal bridges there + * are on this bus. We will distribute the additional available + * buses between hotplug bridges. + */ + for_each_pci_bridge(dev, bus) { + if (dev->is_hotplug_bridge) + hotplug_bridges++; + else + normal_bridges++; + } + + /* + * Scan bridges that are already configured. We don't touch them + * unless they are misconfigured (which will be done in the second + * scan below). + */ + for_each_pci_bridge(dev, bus) { + cmax = max; + max = pci_scan_bridge_extend(bus, dev, max, 0, 0); + + /* + * Reserve one bus for each bridge now to avoid extending + * hotplug bridges too much during the second scan below. + */ + used_buses++; + if (max - cmax > 1) + used_buses += max - cmax - 1; + } + + /* Scan bridges that need to be reconfigured */ + for_each_pci_bridge(dev, bus) { + unsigned int buses = 0; + + if (!hotplug_bridges && normal_bridges == 1) { + /* + * There is only one bridge on the bus (upstream + * port) so it gets all available buses which it + * can then distribute to the possible hotplug + * bridges below. + */ + buses = available_buses; + } else if (dev->is_hotplug_bridge) { + /* + * Distribute the extra buses between hotplug + * bridges if any. + */ + buses = available_buses / hotplug_bridges; + buses = min(buses, available_buses - used_buses + 1); + } + + cmax = max; + max = pci_scan_bridge_extend(bus, dev, cmax, buses, 1); + /* One bus is already accounted so don't add it again */ + if (max - cmax > 1) + used_buses += max - cmax - 1; + } + + /* + * Make sure a hotplug bridge has at least the minimum requested + * number of buses but allow it to grow up to the maximum available + * bus number if there is room. + */ + if (bus->self && bus->self->is_hotplug_bridge) { + used_buses = max_t(unsigned int, available_buses, + pci_hotplug_bus_size - 1); + if (max - start < used_buses) { + max = start + used_buses; + + /* Do not allocate more buses than we have room left */ + if (max > bus->busn_res.end) + max = bus->busn_res.end; + + dev_dbg(&bus->dev, "%pR extended by %#02x\n", + &bus->busn_res, max - start); + } + } + + /* + * We've scanned the bus and so we know all about what's on + * the other side of any bridges that may be on this bus plus + * any devices. + * + * Return how far we've got finding sub-buses. + */ + dev_dbg(&bus->dev, "bus scan returning with max=%02x\n", max); + return max; +} + +/** + * pci_scan_child_bus() - Scan devices below a bus + * @bus: Bus to scan for devices + * + * Scans devices below @bus including subordinate buses. Returns new + * subordinate number including all the found devices. + */ +unsigned int pci_scan_child_bus(struct pci_bus *bus) +{ + return pci_scan_child_bus_extend(bus, 0); +} +EXPORT_SYMBOL_GPL(pci_scan_child_bus); + +/** + * pcibios_root_bridge_prepare - Platform-specific host bridge setup + * @bridge: Host bridge to set up + * + * Default empty implementation. Replace with an architecture-specific setup + * routine, if necessary. + */ +int __weak pcibios_root_bridge_prepare(struct pci_host_bridge *bridge) +{ + return 0; +} + +void __weak pcibios_add_bus(struct pci_bus *bus) +{ +} + +void __weak pcibios_remove_bus(struct pci_bus *bus) +{ +} + +struct pci_bus *pci_create_root_bus(struct device *parent, int bus, + struct pci_ops *ops, void *sysdata, struct list_head *resources) +{ + int error; + struct pci_host_bridge *bridge; + + bridge = pci_alloc_host_bridge(0); + if (!bridge) + return NULL; + + bridge->dev.parent = parent; + + list_splice_init(resources, &bridge->windows); + bridge->sysdata = sysdata; + bridge->busnr = bus; + bridge->ops = ops; + + error = pci_register_host_bridge(bridge); + if (error < 0) + goto err_out; + + return bridge->bus; + +err_out: + put_device(&bridge->dev); + return NULL; +} +EXPORT_SYMBOL_GPL(pci_create_root_bus); + +int pci_host_probe(struct pci_host_bridge *bridge) +{ + struct pci_bus *bus, *child; + int ret; + + ret = pci_scan_root_bus_bridge(bridge); + if (ret < 0) { + dev_err(bridge->dev.parent, "Scanning root bridge failed"); + return ret; + } + + bus = bridge->bus; + + /* + * We insert PCI resources into the iomem_resource and + * ioport_resource trees in either pci_bus_claim_resources() + * or pci_bus_assign_resources(). + */ + if (pci_has_flag(PCI_PROBE_ONLY)) { + pci_bus_claim_resources(bus); + } else { + pci_bus_size_bridges(bus); + pci_bus_assign_resources(bus); + + list_for_each_entry(child, &bus->children, node) + pcie_bus_configure_settings(child); + } + + pci_bus_add_devices(bus); + return 0; +} +EXPORT_SYMBOL_GPL(pci_host_probe); + +int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int bus_max) +{ + struct resource *res = &b->busn_res; + struct resource *parent_res, *conflict; + + res->start = bus; + res->end = bus_max; + res->flags = IORESOURCE_BUS; + + if (!pci_is_root_bus(b)) + parent_res = &b->parent->busn_res; + else { + parent_res = get_pci_domain_busn_res(pci_domain_nr(b)); + res->flags |= IORESOURCE_PCI_FIXED; + } + + conflict = request_resource_conflict(parent_res, res); + + if (conflict) + dev_info(&b->dev, + "busn_res: can not insert %pR under %s%pR (conflicts with %s %pR)\n", + res, pci_is_root_bus(b) ? "domain " : "", + parent_res, conflict->name, conflict); + + return conflict == NULL; +} + +int pci_bus_update_busn_res_end(struct pci_bus *b, int bus_max) +{ + struct resource *res = &b->busn_res; + struct resource old_res = *res; + resource_size_t size; + int ret; + + if (res->start > bus_max) + return -EINVAL; + + size = bus_max - res->start + 1; + ret = adjust_resource(res, res->start, size); + dev_info(&b->dev, "busn_res: %pR end %s updated to %02x\n", + &old_res, ret ? "can not be" : "is", bus_max); + + if (!ret && !res->parent) + pci_bus_insert_busn_res(b, res->start, res->end); + + return ret; +} + +void pci_bus_release_busn_res(struct pci_bus *b) +{ + struct resource *res = &b->busn_res; + int ret; + + if (!res->flags || !res->parent) + return; + + ret = release_resource(res); + dev_info(&b->dev, "busn_res: %pR %s released\n", + res, ret ? "can not be" : "is"); +} + +int pci_scan_root_bus_bridge(struct pci_host_bridge *bridge) +{ + struct resource_entry *window; + bool found = false; + struct pci_bus *b; + int max, bus, ret; + + if (!bridge) + return -EINVAL; + + resource_list_for_each_entry(window, &bridge->windows) + if (window->res->flags & IORESOURCE_BUS) { + bridge->busnr = window->res->start; + found = true; + break; + } + + ret = pci_register_host_bridge(bridge); + if (ret < 0) + return ret; + + b = bridge->bus; + bus = bridge->busnr; + + if (!found) { + dev_info(&b->dev, + "No busn resource found for root bus, will use [bus %02x-ff]\n", + bus); + pci_bus_insert_busn_res(b, bus, 255); + } + + max = pci_scan_child_bus(b); + + if (!found) + pci_bus_update_busn_res_end(b, max); + + return 0; +} +EXPORT_SYMBOL(pci_scan_root_bus_bridge); + +struct pci_bus *pci_scan_root_bus(struct device *parent, int bus, + struct pci_ops *ops, void *sysdata, struct list_head *resources) +{ + struct resource_entry *window; + bool found = false; + struct pci_bus *b; + int max; + + resource_list_for_each_entry(window, resources) + if (window->res->flags & IORESOURCE_BUS) { + found = true; + break; + } + + b = pci_create_root_bus(parent, bus, ops, sysdata, resources); + if (!b) + return NULL; + + if (!found) { + dev_info(&b->dev, + "No busn resource found for root bus, will use [bus %02x-ff]\n", + bus); + pci_bus_insert_busn_res(b, bus, 255); + } + + max = pci_scan_child_bus(b); + + if (!found) + pci_bus_update_busn_res_end(b, max); + + return b; +} +EXPORT_SYMBOL(pci_scan_root_bus); + +struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops, + void *sysdata) +{ + LIST_HEAD(resources); + struct pci_bus *b; + + pci_add_resource(&resources, &ioport_resource); + pci_add_resource(&resources, &iomem_resource); + pci_add_resource(&resources, &busn_resource); + b = pci_create_root_bus(NULL, bus, ops, sysdata, &resources); + if (b) { + pci_scan_child_bus(b); + } else { + pci_free_resource_list(&resources); + } + return b; +} +EXPORT_SYMBOL(pci_scan_bus); + +/** + * pci_rescan_bus_bridge_resize - Scan a PCI bus for devices + * @bridge: PCI bridge for the bus to scan + * + * Scan a PCI bus and child buses for new devices, add them, + * and enable them, resizing bridge mmio/io resource if necessary + * and possible. The caller must ensure the child devices are already + * removed for resizing to occur. + * + * Returns the max number of subordinate bus discovered. + */ +unsigned int pci_rescan_bus_bridge_resize(struct pci_dev *bridge) +{ + unsigned int max; + struct pci_bus *bus = bridge->subordinate; + + max = pci_scan_child_bus(bus); + + pci_assign_unassigned_bridge_resources(bridge); + + pci_bus_add_devices(bus); + + return max; +} + +/** + * pci_rescan_bus - Scan a PCI bus for devices + * @bus: PCI bus to scan + * + * Scan a PCI bus and child buses for new devices, add them, + * and enable them. + * + * Returns the max number of subordinate bus discovered. + */ +unsigned int pci_rescan_bus(struct pci_bus *bus) +{ + unsigned int max; + + max = pci_scan_child_bus(bus); + pci_assign_unassigned_bus_resources(bus); + pci_bus_add_devices(bus); + + return max; +} +EXPORT_SYMBOL_GPL(pci_rescan_bus); + +/* + * pci_rescan_bus(), pci_rescan_bus_bridge_resize() and PCI device removal + * routines should always be executed under this mutex. + */ +static DEFINE_MUTEX(pci_rescan_remove_lock); + +void pci_lock_rescan_remove(void) +{ + mutex_lock(&pci_rescan_remove_lock); +} +EXPORT_SYMBOL_GPL(pci_lock_rescan_remove); + +void pci_unlock_rescan_remove(void) +{ + mutex_unlock(&pci_rescan_remove_lock); +} +EXPORT_SYMBOL_GPL(pci_unlock_rescan_remove); + +static int __init pci_sort_bf_cmp(const struct device *d_a, + const struct device *d_b) +{ + const struct pci_dev *a = to_pci_dev(d_a); + const struct pci_dev *b = to_pci_dev(d_b); + + if (pci_domain_nr(a->bus) < pci_domain_nr(b->bus)) return -1; + else if (pci_domain_nr(a->bus) > pci_domain_nr(b->bus)) return 1; + + if (a->bus->number < b->bus->number) return -1; + else if (a->bus->number > b->bus->number) return 1; + + if (a->devfn < b->devfn) return -1; + else if (a->devfn > b->devfn) return 1; + + return 0; +} + +void __init pci_sort_breadthfirst(void) +{ + bus_sort_breadthfirst(&pci_bus_type, &pci_sort_bf_cmp); +} + +int pci_hp_add_bridge(struct pci_dev *dev) +{ + struct pci_bus *parent = dev->bus; + int busnr, start = parent->busn_res.start; + unsigned int available_buses = 0; + int end = parent->busn_res.end; + + for (busnr = start; busnr <= end; busnr++) { + if (!pci_find_bus(pci_domain_nr(parent), busnr)) + break; + } + if (busnr-- > end) { + pci_err(dev, "No bus number available for hot-added bridge\n"); + return -1; + } + + /* Scan bridges that are already configured */ + busnr = pci_scan_bridge(parent, dev, busnr, 0); + + /* + * Distribute the available bus numbers between hotplug-capable + * bridges to make extending the chain later possible. + */ + available_buses = end - busnr; + + /* Scan bridges that need to be reconfigured */ + pci_scan_bridge_extend(parent, dev, busnr, available_buses, 1); + + if (!dev->subordinate) + return -1; + + return 0; +} +EXPORT_SYMBOL_GPL(pci_hp_add_bridge); |