The following commit has been merged into the x86/irq branch of tip: Commit-ID: c9df2d2677e823a110456bedd4357360b9ee2eda Gitweb: https://git.kernel.org/tip/c9df2d2677e823a110456bedd4357360b9ee2eda Author: Maciej W. Rozycki <macro@xxxxxxxxxxx> AuthorDate: Sun, 02 Jan 2022 23:24:41 Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx> CommitterDate: Wed, 02 Feb 2022 21:27:55 +01:00 x86/PCI: Handle IRQ swizzling with PIRQ routers Similarly to MP-tables PIRQ routing tables may not list devices behind PCI-to-PCI bridges, leading to interrupt routing failures, e.g.: pci 0000:00:07.0: PIIX/ICH IRQ router [8086:7000] pci 0000:02:00.0: ignoring bogus IRQ 255 pci 0000:02:01.0: ignoring bogus IRQ 255 pci 0000:02:02.0: ignoring bogus IRQ 255 pci 0000:04:00.0: ignoring bogus IRQ 255 pci 0000:04:00.3: ignoring bogus IRQ 255 pci 0000:00:11.0: PCI INT A -> PIRQ 63, mask deb8, excl 0c20 pci 0000:00:11.0: PCI INT A -> newirq 0 PCI: setting IRQ 11 as level-triggered pci 0000:00:11.0: found PCI INT A -> IRQ 11 pci 0000:00:11.0: sharing IRQ 11 with 0000:00:07.2 pci 0000:02:00.0: PCI INT A not found in routing table pci 0000:02:01.0: PCI INT A not found in routing table pci 0000:02:02.0: PCI INT A not found in routing table pci 0000:04:00.0: PCI INT A not found in routing table pci 0000:04:00.3: PCI INT D not found in routing table pci 0000:06:05.0: PCI INT A not found in routing table pci 0000:06:08.0: PCI INT A not found in routing table pci 0000:06:08.1: PCI INT B not found in routing table pci 0000:06:08.2: PCI INT C not found in routing table and consequently non-working devices. Since PCI-to-PCI bridges have a standardised way of routing interrupts by the means of swizzling do it for configurations that use a PIRQ router as well, like with APIC-based setups, and use the determined corresponding topmost bridge's interrupt pin assignment to route a given device's interrupt: pci 0000:00:07.0: PIIX/ICH IRQ router [8086:7000] pci 0000:02:00.0: ignoring bogus IRQ 255 pci 0000:02:01.0: ignoring bogus IRQ 255 pci 0000:02:02.0: ignoring bogus IRQ 255 pci 0000:04:00.0: ignoring bogus IRQ 255 pci 0000:04:00.3: ignoring bogus IRQ 255 pci 0000:00:11.0: PCI INT A -> PIRQ 63, mask deb8, excl 0c20 pci 0000:00:11.0: PCI INT A -> newirq 0 PCI: setting IRQ 11 as level-triggered pci 0000:00:11.0: found PCI INT A -> IRQ 11 pci 0000:00:11.0: sharing IRQ 11 with 0000:00:07.2 pci 0000:02:00.0: using bridge 0000:00:11.0 INT A to get INT A pci 0000:00:11.0: sharing IRQ 11 with 0000:02:00.0 pci 0000:02:01.0: using bridge 0000:00:11.0 INT B to get INT A pci 0000:02:02.0: using bridge 0000:00:11.0 INT C to get INT A pci 0000:04:00.0: using bridge 0000:00:11.0 INT B to get INT A pci 0000:04:00.3: using bridge 0000:00:11.0 INT A to get INT D pci 0000:00:11.0: sharing IRQ 11 with 0000:04:00.3 pci 0000:06:05.0: using bridge 0000:00:11.0 INT D to get INT A pci 0000:06:08.0: using bridge 0000:00:11.0 INT C to get INT A pci 0000:06:08.1: using bridge 0000:00:11.0 INT D to get INT B pci 0000:06:08.2: using bridge 0000:00:11.0 INT A to get INT C pci 0000:00:11.0: sharing IRQ 11 with 0000:06:08.2 pci 0000:02:01.0: using bridge 0000:00:11.0 INT B to get INT A pci 0000:02:01.0: PCI INT A -> PIRQ 60, mask deb8, excl 0c20 pci 0000:02:01.0: PCI INT A -> newirq 0 PCI: setting IRQ 10 as level-triggered pci 0000:02:01.0: found PCI INT A -> IRQ 10 pci 0000:02:01.0: sharing IRQ 10 with 0000:00:14.0 pci 0000:02:00.0: using bridge 0000:00:11.0 INT A to get INT A pci 0000:02:01.0: using bridge 0000:00:11.0 INT B to get INT A pci 0000:02:02.0: using bridge 0000:00:11.0 INT C to get INT A pci 0000:04:00.0: using bridge 0000:00:11.0 INT B to get INT A pci 0000:02:01.0: sharing IRQ 10 with 0000:04:00.0 pci 0000:04:00.3: using bridge 0000:00:11.0 INT A to get INT D pci 0000:06:05.0: using bridge 0000:00:11.0 INT D to get INT A pci 0000:06:08.0: using bridge 0000:00:11.0 INT C to get INT A pci 0000:06:08.1: using bridge 0000:00:11.0 INT D to get INT B pci 0000:06:08.2: using bridge 0000:00:11.0 INT A to get INT C pci 0000:02:02.0: using bridge 0000:00:11.0 INT C to get INT A pci 0000:02:02.0: PCI INT A -> PIRQ 61, mask deb8, excl 0c20 pci 0000:02:02.0: PCI INT A -> newirq 0 PCI: setting IRQ 5 as level-triggered pci 0000:02:02.0: found PCI INT A -> IRQ 5 pci 0000:02:02.0: sharing IRQ 5 with 0000:00:13.0 pci 0000:02:00.0: using bridge 0000:00:11.0 INT A to get INT A pci 0000:02:01.0: using bridge 0000:00:11.0 INT B to get INT A pci 0000:02:02.0: using bridge 0000:00:11.0 INT C to get INT A pci 0000:04:00.0: using bridge 0000:00:11.0 INT B to get INT A pci 0000:04:00.3: using bridge 0000:00:11.0 INT A to get INT D pci 0000:06:05.0: using bridge 0000:00:11.0 INT D to get INT A pci 0000:06:08.0: using bridge 0000:00:11.0 INT C to get INT A pci 0000:02:02.0: sharing IRQ 5 with 0000:06:08.0 pci 0000:06:08.1: using bridge 0000:00:11.0 INT D to get INT B pci 0000:06:08.2: using bridge 0000:00:11.0 INT A to get INT C pci 0000:06:05.0: using bridge 0000:00:11.0 INT D to get INT A pci 0000:06:05.0: PCI INT A -> PIRQ 62, mask deb8, excl 0c20 pci 0000:06:05.0: PCI INT A -> newirq 0 pci 0000:06:05.0: found PCI INT A -> IRQ 5 pci 0000:06:05.0: sharing IRQ 5 with 0000:00:12.0 pci 0000:02:00.0: using bridge 0000:00:11.0 INT A to get INT A pci 0000:02:01.0: using bridge 0000:00:11.0 INT B to get INT A pci 0000:02:02.0: using bridge 0000:00:11.0 INT C to get INT A pci 0000:04:00.0: using bridge 0000:00:11.0 INT B to get INT A pci 0000:04:00.3: using bridge 0000:00:11.0 INT A to get INT D pci 0000:06:05.0: using bridge 0000:00:11.0 INT D to get INT A pci 0000:06:08.0: using bridge 0000:00:11.0 INT C to get INT A pci 0000:06:08.1: using bridge 0000:00:11.0 INT D to get INT B pci 0000:06:05.0: sharing IRQ 5 with 0000:06:08.1 pci 0000:06:08.2: using bridge 0000:00:11.0 INT A to get INT C Adjust log messages accordingly. Signed-off-by: Maciej W. Rozycki <macro@xxxxxxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/alpine.DEB.2.21.2201020158320.56863@xxxxxxxxxxxxxxxxx --- arch/x86/pci/irq.c | 60 +++++++++++++++++++++++++++++++++++---------- 1 file changed, 47 insertions(+), 13 deletions(-) diff --git a/arch/x86/pci/irq.c b/arch/x86/pci/irq.c index dcb9c21..bd32e4b 100644 --- a/arch/x86/pci/irq.c +++ b/arch/x86/pci/irq.c @@ -1138,7 +1138,7 @@ static void __init pirq_find_router(struct irq_router *r) * for motherboard devices, so if a complete match is found, then give * it precedence over a slot match. */ -static struct irq_info *pirq_get_info(struct pci_dev *dev) +static struct irq_info *pirq_get_dev_info(struct pci_dev *dev) { struct irq_routing_table *rt = pirq_table; int entries = (rt->size - sizeof(struct irq_routing_table)) / @@ -1157,11 +1157,42 @@ static struct irq_info *pirq_get_info(struct pci_dev *dev) return slotinfo; } +/* + * Buses behind bridges are typically not listed in the PIRQ routing table. + * Do the usual dance then and walk the tree of bridges up adjusting the + * pin number accordingly on the way until the originating root bus device + * has been reached and then use its routing information. + */ +static struct irq_info *pirq_get_info(struct pci_dev *dev, u8 *pin) +{ + struct pci_dev *temp_dev = dev; + struct irq_info *info; + u8 temp_pin = *pin; + u8 dpin = temp_pin; + + info = pirq_get_dev_info(dev); + while (!info && temp_dev->bus->parent) { + struct pci_dev *bridge = temp_dev->bus->self; + + temp_pin = pci_swizzle_interrupt_pin(temp_dev, temp_pin); + info = pirq_get_dev_info(bridge); + if (info) + dev_warn(&dev->dev, + "using bridge %s INT %c to get INT %c\n", + pci_name(bridge), + 'A' + temp_pin - 1, 'A' + dpin - 1); + + temp_dev = bridge; + } + *pin = temp_pin; + return info; +} + static int pcibios_lookup_irq(struct pci_dev *dev, int assign) { - u8 pin; struct irq_info *info; int i, pirq, newirq; + u8 dpin, pin; int irq = 0; u32 mask; struct irq_router *r = &pirq_router; @@ -1169,8 +1200,8 @@ static int pcibios_lookup_irq(struct pci_dev *dev, int assign) char *msg = NULL; /* Find IRQ pin */ - pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin); - if (!pin) { + pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &dpin); + if (!dpin) { dev_dbg(&dev->dev, "no interrupt pin\n"); return 0; } @@ -1183,20 +1214,21 @@ static int pcibios_lookup_irq(struct pci_dev *dev, int assign) if (!pirq_table) return 0; - info = pirq_get_info(dev); + pin = dpin; + info = pirq_get_info(dev, &pin); if (!info) { dev_dbg(&dev->dev, "PCI INT %c not found in routing table\n", - 'A' + pin - 1); + 'A' + dpin - 1); return 0; } pirq = info->irq[pin - 1].link; mask = info->irq[pin - 1].bitmap; if (!pirq) { - dev_dbg(&dev->dev, "PCI INT %c not routed\n", 'A' + pin - 1); + dev_dbg(&dev->dev, "PCI INT %c not routed\n", 'A' + dpin - 1); return 0; } dev_dbg(&dev->dev, "PCI INT %c -> PIRQ %02x, mask %04x, excl %04x", - 'A' + pin - 1, pirq, mask, pirq_table->exclusive_irqs); + 'A' + dpin - 1, pirq, mask, pirq_table->exclusive_irqs); mask &= pcibios_irq_mask; /* Work around broken HP Pavilion Notebooks which assign USB to @@ -1238,7 +1270,7 @@ static int pcibios_lookup_irq(struct pci_dev *dev, int assign) newirq = i; } } - dev_dbg(&dev->dev, "PCI INT %c -> newirq %d", 'A' + pin - 1, newirq); + dev_dbg(&dev->dev, "PCI INT %c -> newirq %d", 'A' + dpin - 1, newirq); /* Check if it is hardcoded */ if ((pirq & 0xf0) == 0xf0) { @@ -1272,15 +1304,17 @@ static int pcibios_lookup_irq(struct pci_dev *dev, int assign) return 0; } } - dev_info(&dev->dev, "%s PCI INT %c -> IRQ %d\n", msg, 'A' + pin - 1, irq); + dev_info(&dev->dev, "%s PCI INT %c -> IRQ %d\n", + msg, 'A' + dpin - 1, irq); /* Update IRQ for all devices with the same pirq value */ for_each_pci_dev(dev2) { - pci_read_config_byte(dev2, PCI_INTERRUPT_PIN, &pin); - if (!pin) + pci_read_config_byte(dev2, PCI_INTERRUPT_PIN, &dpin); + if (!dpin) continue; - info = pirq_get_info(dev2); + pin = dpin; + info = pirq_get_info(dev2, &pin); if (!info) continue; if (info->irq[pin - 1].link == pirq) {
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