/* * pci_irq.c - ACPI PCI Interrupt Routing ($Revision: 11 $) * * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> * Copyright (C) 2002 Dominik Brodowski <devel@brodo.de> * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or (at * your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/types.h> #include <linux/proc_fs.h> #include <linux/spinlock.h> #include <linux/pm.h> #include <linux/pci.h> #include <linux/acpi.h> #include <acpi/acpi_bus.h> #include <acpi/acpi_drivers.h> #define _COMPONENT ACPI_PCI_COMPONENT ACPI_MODULE_NAME("pci_irq"); static struct acpi_prt_list acpi_prt; static DEFINE_SPINLOCK(acpi_prt_lock); /* -------------------------------------------------------------------------- PCI IRQ Routing Table (PRT) Support -------------------------------------------------------------------------- */ static struct acpi_prt_entry *acpi_pci_irq_find_prt_entry(int segment, int bus, int device, int pin) { struct list_head *node = NULL; struct acpi_prt_entry *entry = NULL; if (!acpi_prt.count) return NULL; /* * Parse through all PRT entries looking for a match on the specified * PCI device's segment, bus, device, and pin (don't care about func). * */ spin_lock(&acpi_prt_lock); list_for_each(node, &acpi_prt.entries) { entry = list_entry(node, struct acpi_prt_entry, node); if ((segment == entry->id.segment) && (bus == entry->id.bus) && (device == entry->id.device) && (pin == entry->pin)) { spin_unlock(&acpi_prt_lock); return entry; } } spin_unlock(&acpi_prt_lock); return NULL; } static int acpi_pci_irq_add_entry(acpi_handle handle, int segment, int bus, struct acpi_pci_routing_table *prt) { struct acpi_prt_entry *entry = NULL; if (!prt) return -EINVAL; entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL); if (!entry) return -ENOMEM; entry->id.segment = segment; entry->id.bus = bus; entry->id.device = (prt->address >> 16) & 0xFFFF; entry->id.function = prt->address & 0xFFFF; entry->pin = prt->pin; /* * 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.handle); entry->link.index = prt->source_index; } /* * 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. */ else entry->link.index = prt->source_index; ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO, " %02X:%02X:%02X[%c] -> %s[%d]\n", entry->id.segment, entry->id.bus, entry->id.device, ('A' + entry->pin), prt->source, entry->link.index)); spin_lock(&acpi_prt_lock); list_add_tail(&entry->node, &acpi_prt.entries); acpi_prt.count++; spin_unlock(&acpi_prt_lock); return 0; } static void acpi_pci_irq_del_entry(int segment, int bus, struct acpi_prt_entry *entry) { if (segment == entry->id.segment && bus == entry->id.bus) { acpi_prt.count--; list_del(&entry->node); kfree(entry); } } int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus) { acpi_status status = AE_OK; char *pathname = NULL; struct acpi_buffer buffer = { 0, NULL }; struct acpi_pci_routing_table *prt = NULL; struct acpi_pci_routing_table *entry = NULL; static int first_time = 1; pathname = kzalloc(ACPI_PATHNAME_MAX, GFP_KERNEL); if (!pathname) return -ENOMEM; if (first_time) { acpi_prt.count = 0; INIT_LIST_HEAD(&acpi_prt.entries); first_time = 0; } /* * NOTE: We're given a 'handle' to the _PRT object's parent device * (either a PCI root bridge or PCI-PCI bridge). */ buffer.length = ACPI_PATHNAME_MAX; buffer.pointer = pathname; acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n", pathname); /* * Evaluate this _PRT and add its entries to our global list (acpi_prt). */ buffer.length = 0; buffer.pointer = NULL; kfree(pathname); status = acpi_get_irq_routing_table(handle, &buffer); if (status != AE_BUFFER_OVERFLOW) { ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRT [%s]", acpi_format_exception(status))); return -ENODEV; } prt = kzalloc(buffer.length, GFP_KERNEL); if (!prt) { return -ENOMEM; } buffer.pointer = prt; status = acpi_get_irq_routing_table(handle, &buffer); if (ACPI_FAILURE(status)) { ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRT [%s]", acpi_format_exception(status))); kfree(buffer.pointer); return -ENODEV; } entry = prt; while (entry && (entry->length > 0)) { acpi_pci_irq_add_entry(handle, segment, bus, entry); entry = (struct acpi_pci_routing_table *) ((unsigned long)entry + entry->length); } kfree(prt); return 0; } void acpi_pci_irq_del_prt(int segment, int bus) { struct list_head *node = NULL, *n = NULL; struct acpi_prt_entry *entry = NULL; if (!acpi_prt.count) { return; } printk(KERN_DEBUG "ACPI: Delete PCI Interrupt Routing Table for %x:%x\n", segment, bus); spin_lock(&acpi_prt_lock); list_for_each_safe(node, n, &acpi_prt.entries) { entry = list_entry(node, struct acpi_prt_entry, node); acpi_pci_irq_del_entry(segment, bus, entry); } spin_unlock(&acpi_prt_lock); } /* -------------------------------------------------------------------------- PCI Interrupt Routing Support -------------------------------------------------------------------------- */ typedef int (*irq_lookup_func) (struct acpi_prt_entry *, int *, int *, char **); static int acpi_pci_allocate_irq(struct acpi_prt_entry *entry, int *triggering, int *polarity, char **link) { int irq; if (entry->link.handle) { irq = acpi_pci_link_allocate_irq(entry->link.handle, entry->link.index, triggering, polarity, link); if (irq < 0) { printk(KERN_WARNING PREFIX "Invalid IRQ link routing entry\n"); return -1; } } else { irq = entry->link.index; *triggering = ACPI_LEVEL_SENSITIVE; *polarity = ACPI_ACTIVE_LOW; } ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found IRQ %d\n", irq)); return irq; } static int acpi_pci_free_irq(struct acpi_prt_entry *entry, int *triggering, int *polarity, char **link) { int irq; if (entry->link.handle) { irq = acpi_pci_link_free_irq(entry->link.handle); } else { irq = entry->link.index; } return irq; } /* * acpi_pci_irq_lookup * success: return IRQ >= 0 * failure: return -1 */ static int acpi_pci_irq_lookup(struct pci_bus *bus, int device, int pin, int *triggering, int *polarity, char **link, irq_lookup_func func) { struct acpi_prt_entry *entry = NULL; int segment = pci_domain_nr(bus); int bus_nr = bus->number; int ret; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Searching for PRT entry for %02x:%02x:%02x[%c]\n", segment, bus_nr, device, ('A' + pin))); entry = acpi_pci_irq_find_prt_entry(segment, bus_nr, device, pin); if (!entry) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PRT entry not found\n")); return -1; } ret = func(entry, triggering, polarity, link); return ret; } /* * acpi_pci_irq_derive * success: return IRQ >= 0 * failure: return < 0 */ static int acpi_pci_irq_derive(struct pci_dev *dev, int pin, int *triggering, int *polarity, char **link, irq_lookup_func func) { struct pci_dev *bridge = dev; int irq = -1; u8 bridge_pin = 0; if (!dev) return -EINVAL; /* * 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). */ while (irq < 0 && bridge->bus->self) { pin = (pin + PCI_SLOT(bridge->devfn)) % 4; bridge = bridge->bus->self; if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) { /* PC card has the same IRQ as its cardbridge */ bridge_pin = bridge->pin; if (!bridge_pin) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No interrupt pin configured for device %s\n", pci_name(bridge))); return -1; } /* Pin is from 0 to 3 */ bridge_pin--; pin = bridge_pin; } irq = acpi_pci_irq_lookup(bridge->bus, PCI_SLOT(bridge->devfn), pin, triggering, polarity, link, func); } if (irq < 0) { printk(KERN_WARNING PREFIX "Unable to derive IRQ for device %s\n", pci_name(dev)); return -1; } ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Derive IRQ %d for device %s from %s\n", irq, pci_name(dev), pci_name(bridge))); return irq; } /* * acpi_pci_irq_enable * success: return 0 * failure: return < 0 */ int acpi_pci_irq_enable(struct pci_dev *dev) { int irq = 0; u8 pin = 0; int triggering = ACPI_LEVEL_SENSITIVE; int polarity = ACPI_ACTIVE_LOW; char *link = NULL; int rc; if (!dev) return -EINVAL; pin = dev->pin; if (!pin) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No interrupt pin configured for device %s\n", pci_name(dev))); return 0; } pin--; if (!dev->bus) { printk(KERN_ERR PREFIX "Invalid (NULL) 'bus' field\n"); return -ENODEV; } /* * First we check the PCI IRQ routing table (PRT) for an IRQ. PRT * values override any BIOS-assigned IRQs set during boot. */ irq = acpi_pci_irq_lookup(dev->bus, PCI_SLOT(dev->devfn), pin, &triggering, &polarity, &link, acpi_pci_allocate_irq); /* * If no PRT entry was found, we'll try to derive an IRQ from the * device's parent bridge. */ if (irq < 0) irq = acpi_pci_irq_derive(dev, pin, &triggering, &polarity, &link, acpi_pci_allocate_irq); /* * No IRQ known to the ACPI subsystem - maybe the BIOS / * driver reported one, then use it. Exit in any case. */ if (irq < 0) { printk(KERN_WARNING PREFIX "PCI Interrupt %s[%c]: no GSI", pci_name(dev), ('A' + pin)); /* Interrupt Line values above 0xF are forbidden */ if (dev->irq > 0 && (dev->irq <= 0xF)) { printk(" - using IRQ %d\n", dev->irq); acpi_register_gsi(dev->irq, ACPI_LEVEL_SENSITIVE, ACPI_ACTIVE_LOW); return 0; } else { printk("\n"); return 0; } } rc = acpi_register_gsi(irq, triggering, polarity); if (rc < 0) { printk(KERN_WARNING PREFIX "PCI Interrupt %s[%c]: failed " "to register GSI\n", pci_name(dev), ('A' + pin)); return rc; } dev->irq = rc; printk(KERN_INFO PREFIX "PCI Interrupt %s[%c] -> ", pci_name(dev), 'A' + pin); if (link) printk("Link [%s] -> ", link); printk("GSI %u (%s, %s) -> IRQ %d\n", irq, (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge", (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq); return 0; } EXPORT_SYMBOL(acpi_pci_irq_enable); /* FIXME: implement x86/x86_64 version */ void __attribute__ ((weak)) acpi_unregister_gsi(u32 i) { } void acpi_pci_irq_disable(struct pci_dev *dev) { int gsi = 0; u8 pin = 0; int triggering = ACPI_LEVEL_SENSITIVE; int polarity = ACPI_ACTIVE_LOW; if (!dev || !dev->bus) return; pin = dev->pin; if (!pin) return; pin--; /* * First we check the PCI IRQ routing table (PRT) for an IRQ. */ gsi = acpi_pci_irq_lookup(dev->bus, PCI_SLOT(dev->devfn), pin, &triggering, &polarity, NULL, acpi_pci_free_irq); /* * If no PRT entry was found, we'll try to derive an IRQ from the * device's parent bridge. */ if (gsi < 0) gsi = acpi_pci_irq_derive(dev, pin, &triggering, &polarity, NULL, acpi_pci_free_irq); if (gsi < 0) return; /* * TBD: It might be worth clearing dev->irq by magic constant * (e.g. PCI_UNDEFINED_IRQ). */ printk(KERN_INFO PREFIX "PCI interrupt for device %s disabled\n", pci_name(dev)); acpi_unregister_gsi(gsi); return; }