From 181380b702eee1a9aca51354d7b87c7b08541fcf Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Sat, 16 Feb 2013 11:58:34 -0700 Subject: PCI/ACPI: Don't cache _PRT, and don't associate them with bus numbers Previously, we cached _PRT (PCI routing table, ACPI 5.0 sec 6.2.12) contents and associated each _PRT entry with a PCI bus number. The bus number association means dependencies on PCI device enumeration and bus number assignment, as well as on the PCI/ACPI binding process. After 4f535093cf ("PCI: Put pci_dev in device tree as early as possible"), these dependencies caused the IRQ issues reported by Peter: pci 0000:00:1e.0: PCI bridge to [bus 09] (subtractive decode) pci 0000:00:1e.0: can't derive routing for PCI INT A snd_ctxfi 0000:09:02.0: PCI INT A: no GSI - using ISA IRQ 5 irq 18: nobody cared (try booting with the "irqpoll" option) This patch removes _PRT caching. Instead, we evaluate _PRT as needed in the pci_enable_device() path. This also removes the dependency on PCI bus numbers: we can simply look at the _PRT associated with each bridge as we walk upstream toward the root. [bhelgaas: changelog] Reference: https://bugzilla.kernel.org/show_bug.cgi?id=53561 Reported-and-tested-by: Peter Hurley Suggested-by: Bjorn Helgaas Signed-off-by: Yinghai Lu Signed-off-by: Bjorn Helgaas --- drivers/acpi/pci_irq.c | 102 +++++++++++++++++-------------------------------- 1 file changed, 34 insertions(+), 68 deletions(-) (limited to 'drivers/acpi/pci_irq.c') diff --git a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c index 68a921d0324..41c5e1b799e 100644 --- a/drivers/acpi/pci_irq.c +++ b/drivers/acpi/pci_irq.c @@ -53,9 +53,6 @@ struct acpi_prt_entry { u32 index; /* GSI, or link _CRS index */ }; -static LIST_HEAD(acpi_prt_list); -static DEFINE_SPINLOCK(acpi_prt_lock); - static inline char pin_name(int pin) { return 'A' + pin - 1; @@ -65,28 +62,6 @@ static inline char pin_name(int pin) PCI IRQ Routing Table (PRT) Support -------------------------------------------------------------------------- */ -static struct acpi_prt_entry *acpi_pci_irq_find_prt_entry(struct pci_dev *dev, - int pin) -{ - struct acpi_prt_entry *entry; - int segment = pci_domain_nr(dev->bus); - int bus = dev->bus->number; - int device = PCI_SLOT(dev->devfn); - - spin_lock(&acpi_prt_lock); - list_for_each_entry(entry, &acpi_prt_list, list) { - 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; -} - /* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */ static const struct dmi_system_id medion_md9580[] = { { @@ -184,11 +159,19 @@ static void do_prt_fixups(struct acpi_prt_entry *entry, } } -static int acpi_pci_irq_add_entry(acpi_handle handle, int segment, int bus, - struct acpi_pci_routing_table *prt) +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_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; @@ -237,43 +220,37 @@ static int acpi_pci_irq_add_entry(acpi_handle handle, int segment, int bus, entry->id.device, pin_name(entry->pin), prt->source, entry->index)); - spin_lock(&acpi_prt_lock); - list_add_tail(&entry->list, &acpi_prt_list); - spin_unlock(&acpi_prt_lock); + *entry_ptr = entry; return 0; } -int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus) +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; - /* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */ - status = acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); - if (ACPI_FAILURE(status)) - return -ENODEV; - - printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n", - (char *) buffer.pointer); - - kfree(buffer.pointer); + if (dev->bus->bridge) + handle = ACPI_HANDLE(dev->bus->bridge); - buffer.length = ACPI_ALLOCATE_BUFFER; - buffer.pointer = NULL; + 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)) { - ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRT [%s]", - acpi_format_exception(status))); kfree(buffer.pointer); return -ENODEV; } entry = buffer.pointer; while (entry && (entry->length > 0)) { - acpi_pci_irq_add_entry(handle, segment, bus, entry); + if (!acpi_pci_irq_check_entry(handle, dev, pin, + entry, entry_ptr)) + break; entry = (struct acpi_pci_routing_table *) ((unsigned long)entry + entry->length); } @@ -282,23 +259,6 @@ int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus) return 0; } -void acpi_pci_irq_del_prt(int segment, int bus) -{ - struct acpi_prt_entry *entry, *tmp; - - printk(KERN_DEBUG - "ACPI: Delete PCI Interrupt Routing Table for %04x:%02x\n", - segment, bus); - spin_lock(&acpi_prt_lock); - list_for_each_entry_safe(entry, tmp, &acpi_prt_list, list) { - if (segment == entry->id.segment && bus == entry->id.bus) { - list_del(&entry->list); - kfree(entry); - } - } - spin_unlock(&acpi_prt_lock); -} - /* -------------------------------------------------------------------------- PCI Interrupt Routing Support -------------------------------------------------------------------------- */ @@ -359,12 +319,13 @@ static int acpi_reroute_boot_interrupt(struct pci_dev *dev, static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin) { - struct acpi_prt_entry *entry; + struct acpi_prt_entry *entry = NULL; struct pci_dev *bridge; u8 bridge_pin, orig_pin = pin; + int ret; - entry = acpi_pci_irq_find_prt_entry(dev, pin); - if (entry) { + 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 */ @@ -373,7 +334,7 @@ static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int 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). */ @@ -393,8 +354,8 @@ static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin) pin = bridge_pin; } - entry = acpi_pci_irq_find_prt_entry(bridge, pin); - if (entry) { + ret = acpi_pci_irq_find_prt_entry(bridge, pin, &entry); + if (!ret && entry) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Derived GSI for %s INT %c from %s\n", pci_name(dev), pin_name(orig_pin), @@ -470,6 +431,7 @@ int acpi_pci_irq_enable(struct pci_dev *dev) dev_warn(&dev->dev, "PCI INT %c: no GSI\n", pin_name(pin)); } + return 0; } @@ -477,6 +439,7 @@ int acpi_pci_irq_enable(struct pci_dev *dev) 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; @@ -491,6 +454,7 @@ int acpi_pci_irq_enable(struct pci_dev *dev) (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge", (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq); + kfree(entry); return 0; } @@ -513,6 +477,8 @@ void acpi_pci_irq_disable(struct pci_dev *dev) else gsi = entry->index; + kfree(entry); + /* * TBD: It might be worth clearing dev->irq by magic constant * (e.g. PCI_UNDEFINED_IRQ). -- cgit v1.2.3-70-g09d2