// SPDX-License-Identifier: GPL-2.0-or-later /* * pci_irq.c - ACPI PCI Interrupt Routing ($Revision: 11 $) * * Copyright (C) 2001, 2002 Andy Grover * Copyright (C) 2001, 2002 Paul Diefenbaugh * Copyright (C) 2002 Dominik Brodowski * (c) Copyright 2008 Hewlett-Packard Development Company, L.P. * Bjorn Helgaas */ #define pr_fmt(fmt) "ACPI: PCI: " fmt #include #include #include #include #include #include #include #include #include #include #include struct acpi_prt_entry { struct acpi_pci_id id; u8 pin; acpi_handle link; u32 index; /* GSI, or link _CRS index */ }; static inline char pin_name(int pin) { return 'A' + pin - 1; } /* -------------------------------------------------------------------------- PCI IRQ Routing Table (PRT) Support -------------------------------------------------------------------------- */ /* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */ static const struct dmi_system_id medion_md9580[] = { { .ident = "Medion MD9580-F laptop", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "MEDIONNB"), DMI_MATCH(DMI_PRODUCT_NAME, "A555"), }, }, { } }; /* http://bugzilla.kernel.org/show_bug.cgi?id=5044 */ static const struct dmi_system_id dell_optiplex[] = { { .ident = "Dell Optiplex GX1", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex GX1 600S+"), }, }, { } }; /* http://bugzilla.kernel.org/show_bug.cgi?id=10138 */ static const struct dmi_system_id hp_t5710[] = { { .ident = "HP t5710", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), DMI_MATCH(DMI_PRODUCT_NAME, "hp t5000 series"), DMI_MATCH(DMI_BOARD_NAME, "098Ch"), }, }, { } }; struct prt_quirk { const struct dmi_system_id *system; unsigned int segment; unsigned int bus; unsigned int device; unsigned char pin; const char *source; /* according to BIOS */ const char *actual_source; }; #define PCI_INTX_PIN(c) (c - 'A' + 1) /* * These systems have incorrect _PRT entries. The BIOS claims the PCI * interrupt at the listed segment/bus/device/pin is connected to the first * link device, but it is actually connected to the second. */ static const struct prt_quirk prt_quirks[] = { { medion_md9580, 0, 0, 9, PCI_INTX_PIN('A'), "\\_SB_.PCI0.ISA_.LNKA", "\\_SB_.PCI0.ISA_.LNKB"}, { dell_optiplex, 0, 0, 0xd, PCI_INTX_PIN('A'), "\\_SB_.LNKB", "\\_SB_.LNKA"}, { hp_t5710, 0, 0, 1, PCI_INTX_PIN('A'), "\\_SB_.PCI0.LNK1", "\\_SB_.PCI0.LNK3"}, }; static void do_prt_fixups(struct acpi_prt_entry *entry, struct acpi_pci_routing_table *prt) { int i; const struct prt_quirk *quirk; for (i = 0; i < ARRAY_SIZE(prt_quirks); i++) { quirk = &prt_quirks[i]; /* All current quirks involve link devices, not GSIs */ if (dmi_check_system(quirk->system) && entry->id.segment == quirk->segment && entry->id.bus == quirk->bus && entry->id.device == quirk->device && entry->pin == quirk->pin && !strcmp(prt->source, quirk->source) && strlen(prt->source) >= strlen(quirk->actual_source)) { pr_warn("Firmware reports " "%04x:%02x:%02x PCI INT %c connected to %s; " "changing to %s\n", entry->id.segment, entry->id.bus, entry->id.device, pin_name(entry->pin), prt->source, quirk->actual_source); strcpy(prt->source, quirk->actual_source); } } } static int acpi_pci_irq_check_entry(acpi_handle handle, struct pci_dev *dev, int pin, struct acpi_pci_routing_table *prt, struct acpi_prt_entry **entry_ptr) { int segment = pci_domain_nr(dev->bus); int bus = dev->bus->number; int device = pci_ari_enabled(dev->bus) ? 0 : PCI_SLOT(dev->devfn); struct acpi_prt_entry *entry; if (((prt->address >> 16) & 0xffff) != device || prt->pin + 1 != pin) return -ENODEV; entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL); if (!entry) return -ENOMEM; /* * Note that the _PRT uses 0=INTA, 1=INTB, etc, while PCI uses * 1=INTA, 2=INTB. We use the PCI encoding throughout, so convert * it here. */ entry->id.segment = segment; entry->id.bus = bus; entry->id.device = (prt->address >> 16) & 0xFFFF; entry->pin = prt->pin + 1; do_prt_fixups(entry, prt); entry->index = prt->source_index; /* * Type 1: Dynamic * --------------- * The 'source' field specifies the PCI interrupt link device used to * configure the IRQ assigned to this slot|dev|pin. The 'source_index' * indicates which resource descriptor in the resource template (of * the link device) this interrupt is allocated from. * * NOTE: Don't query the Link Device for IRQ information at this time * because Link Device enumeration may not have occurred yet * (e.g. exists somewhere 'below' this _PRT entry in the ACPI * namespace). */ if (prt->source[0]) acpi_get_handle(handle, prt->source, &entry->link); /* * Type 2: Static * -------------- * The 'source' field is NULL, and the 'source_index' field specifies * the IRQ value, which is hardwired to specific interrupt inputs on * the interrupt controller. */ pr_debug("%04x:%02x:%02x[%c] -> %s[%d]\n", entry->id.segment, entry->id.bus, entry->id.device, pin_name(entry->pin), prt->source, entry->index); *entry_ptr = entry; return 0; } static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev, int pin, struct acpi_prt_entry **entry_ptr) { acpi_status status; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; struct acpi_pci_routing_table *entry; acpi_handle handle = NULL; if (dev->bus->bridge) handle = ACPI_HANDLE(dev->bus->bridge); if (!handle) return -ENODEV; /* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */ status = acpi_get_irq_routing_table(handle, &buffer); if (ACPI_FAILURE(status)) { kfree(buffer.pointer); return -ENODEV; } entry = buffer.pointer; while (entry && (entry->length > 0)) { if (!acpi_pci_irq_check_entry(handle, dev, pin, entry, entry_ptr)) break; entry = (struct acpi_pci_routing_table *) ((unsigned long)entry + entry->length); } kfree(buffer.pointer); return 0; } /* -------------------------------------------------------------------------- PCI Interrupt Routing Support -------------------------------------------------------------------------- */ #ifdef CONFIG_X86_IO_APIC extern int noioapicquirk; extern int noioapicreroute; static int bridge_has_boot_interrupt_variant(struct pci_bus *bus) { struct pci_bus *bus_it; for (bus_it = bus ; bus_it ; bus_it = bus_it->parent) { if (!bus_it->self) return 0; if (bus_it->self->irq_reroute_variant) return bus_it->self->irq_reroute_variant; } return 0; } /* * Some chipsets (e.g. Intel 6700PXH) generate a legacy INTx when the IRQ * entry in the chipset's IO-APIC is masked (as, e.g. the RT kernel does * during interrupt handling). When this INTx generation cannot be disabled, * we reroute these interrupts to their legacy equivalent to get rid of * spurious interrupts. */ static int acpi_reroute_boot_interrupt(struct pci_dev *dev, struct acpi_prt_entry *entry) { if (noioapicquirk || noioapicreroute) { return 0; } else { switch (bridge_has_boot_interrupt_variant(dev->bus)) { case 0: /* no rerouting necessary */ return 0; case INTEL_IRQ_REROUTE_VARIANT: /* * Remap according to INTx routing table in 6700PXH * specs, intel order number 302628-002, section * 2.15.2. Other chipsets (80332, ...) have the same * mapping and are handled here as well. */ dev_info(&dev->dev, "PCI IRQ %d -> rerouted to legacy " "IRQ %d\n", entry->index, (entry->index % 4) + 16); entry->index = (entry->index % 4) + 16; return 1; default: dev_warn(&dev->dev, "Cannot reroute IRQ %d to legacy " "IRQ: unknown mapping\n", entry->index); return -1; } } } #endif /* CONFIG_X86_IO_APIC */ struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin) { struct acpi_prt_entry *entry = NULL; struct pci_dev *bridge; u8 bridge_pin, orig_pin = pin; int ret; ret = acpi_pci_irq_find_prt_entry(dev, pin, &entry); if (!ret && entry) { #ifdef CONFIG_X86_IO_APIC acpi_reroute_boot_interrupt(dev, entry); #endif /* CONFIG_X86_IO_APIC */ dev_dbg(&dev->dev, "Found [%c] _PRT entry\n", pin_name(pin)); return entry; } /* * Attempt to derive an IRQ for this device from a parent bridge's * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge). */ bridge = dev->bus->self; while (bridge) { pin = pci_swizzle_interrupt_pin(dev, pin); if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) { /* PC card has the same IRQ as its cardbridge */ bridge_pin = bridge->pin; if (!bridge_pin) { dev_dbg(&bridge->dev, "No interrupt pin configured\n"); return NULL; } pin = bridge_pin; } ret = acpi_pci_irq_find_prt_entry(bridge, pin, &entry); if (!ret && entry) { dev_dbg(&dev->dev, "Derived GSI INT %c from %s\n", pin_name(orig_pin), pci_name(bridge)); return entry; } dev = bridge; bridge = dev->bus->self; } dev_warn(&dev->dev, "can't derive routing for PCI INT %c\n", pin_name(orig_pin)); return NULL; } #if IS_ENABLED(CONFIG_ISA) || IS_ENABLED(CONFIG_EISA) static int acpi_isa_register_gsi(struct pci_dev *dev) { u32 dev_gsi; /* Interrupt Line values above 0xF are forbidden */ if (dev->irq > 0 && (dev->irq <= 0xF) && acpi_isa_irq_available(dev->irq) && (acpi_isa_irq_to_gsi(dev->irq, &dev_gsi) == 0)) { dev_warn(&dev->dev, "PCI INT %c: no GSI - using ISA IRQ %d\n", pin_name(dev->pin), dev->irq); acpi_register_gsi(&dev->dev, dev_gsi, ACPI_LEVEL_SENSITIVE, ACPI_ACTIVE_LOW); return 0; } return -EINVAL; } #else static inline int acpi_isa_register_gsi(struct pci_dev *dev) { return -ENODEV; } #endif static inline bool acpi_pci_irq_valid(struct pci_dev *dev, u8 pin) { #ifdef CONFIG_X86 /* * On x86 irq line 0xff means "unknown" or "no connection" * (PCI 3.0, Section 6.2.4, footnote on page 223). */ if (dev->irq == 0xff) { dev->irq = IRQ_NOTCONNECTED; dev_warn(&dev->dev, "PCI INT %c: not connected\n", pin_name(pin)); return false; } #endif return true; } int acpi_pci_irq_enable(struct pci_dev *dev) { struct acpi_prt_entry *entry; int gsi; u8 pin; int triggering = ACPI_LEVEL_SENSITIVE; /* * On ARM systems with the GIC interrupt model, or LoongArch * systems with the LPIC interrupt model, level interrupts * are always polarity high by specification; PCI legacy * IRQs lines are inverted before reaching the interrupt * controller and must therefore be considered active high * as default. */ int polarity = acpi_irq_model == ACPI_IRQ_MODEL_GIC || acpi_irq_model == ACPI_IRQ_MODEL_LPIC ? ACPI_ACTIVE_HIGH : ACPI_ACTIVE_LOW; char *link = NULL; char link_desc[16]; int rc; pin = dev->pin; if (!pin) { dev_dbg(&dev->dev, "No interrupt pin configured\n"); return 0; } if (dev->irq_managed && dev->irq > 0) return 0; entry = acpi_pci_irq_lookup(dev, pin); if (!entry) { /* * IDE legacy mode controller IRQs are magic. Why do compat * extensions always make such a nasty mess. */ if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE && (dev->class & 0x05) == 0) return 0; } if (entry) { if (entry->link) gsi = acpi_pci_link_allocate_irq(entry->link, entry->index, &triggering, &polarity, &link); else gsi = entry->index; } else gsi = -1; if (gsi < 0) { /* * No IRQ known to the ACPI subsystem - maybe the BIOS / * driver reported one, then use it. Exit in any case. */ if (!acpi_pci_irq_valid(dev, pin)) { kfree(entry); return 0; } if (acpi_isa_register_gsi(dev)) dev_warn(&dev->dev, "PCI INT %c: no GSI\n", pin_name(pin)); kfree(entry); return 0; } rc = acpi_register_gsi(&dev->dev, gsi, triggering, polarity); if (rc < 0) { dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n", pin_name(pin)); kfree(entry); return rc; } dev->irq = rc; dev->irq_managed = 1; if (link) snprintf(link_desc, sizeof(link_desc), " -> Link[%s]", link); else link_desc[0] = '\0'; dev_dbg(&dev->dev, "PCI INT %c%s -> GSI %u (%s, %s) -> IRQ %d\n", pin_name(pin), link_desc, gsi, (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge", (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq); kfree(entry); return 0; } void acpi_pci_irq_disable(struct pci_dev *dev) { struct acpi_prt_entry *entry; int gsi; u8 pin; pin = dev->pin; if (!pin || !dev->irq_managed || dev->irq <= 0) return; /* Keep IOAPIC pin configuration when suspending */ if (dev->dev.power.is_prepared) return; #ifdef CONFIG_PM if (dev->dev.power.runtime_status == RPM_SUSPENDING) return; #endif entry = acpi_pci_irq_lookup(dev, pin); if (!entry) return; if (entry->link) gsi = acpi_pci_link_free_irq(entry->link); else gsi = entry->index; kfree(entry); /* * TBD: It might be worth clearing dev->irq by magic constant * (e.g. PCI_UNDEFINED_IRQ). */ dev_dbg(&dev->dev, "PCI INT %c disabled\n", pin_name(pin)); if (gsi >= 0) { acpi_unregister_gsi(gsi); dev->irq_managed = 0; } }