From nobody Mon Jun 29 21:06:50 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9EB84C433EF for ; Wed, 2 Feb 2022 20:31:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347154AbiBBUbC (ORCPT ); Wed, 2 Feb 2022 15:31:02 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:48976 "EHLO galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347120AbiBBUas (ORCPT ); Wed, 2 Feb 2022 15:30:48 -0500 Date: Wed, 02 Feb 2022 20:30:46 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1643833847; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=L2beHnRyD57KQHoaZD0r7xoMZxPiSoUs0rlsC2RzkOw=; b=l9B9IC18k+X1R/TCLoDkcxlx2x432ApV7aoQxmrnAFxC5ZWNskWKbVlAan2LVbnLZkk7La WDumprfx6z2YixSOGsOa+OA6B9OxZpMGBDbwjcvlqELxbTQBYqg81pxwi7PpsNWJiYe97f fdtvHx5ZoXgAhqvIs28dAWxlHAdX49VBD2IjEv9lHVSVjVPRK6EfTQIcPAxrDkVCobQIzB Xkb1Y6FxSTU4vf0PlAJREbwbpLbrEAmEV5O4JR1Z8pgbI8soXiYcJMc5WwRfDGqzRnWsCM 526wDGhzMHLEZ3NVZE90se8am8DnJ/zzjLEtN5rGXsKq5cSur22OJtcazo6/Hg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1643833847; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=L2beHnRyD57KQHoaZD0r7xoMZxPiSoUs0rlsC2RzkOw=; b=oNbmQ4GW8fBMl7u5LDZLtKXh7oFWm/frFGL07r5g+dbURkxfl1ji90bdSULA+kNd4D6+7y AGoiK4DomlVzG6BA== From: "tip-bot2 for Maciej W. Rozycki" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: x86/irq] x86/PCI: Handle IRQ swizzling with PIRQ routers Cc: "Maciej W. Rozycki" , Thomas Gleixner , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: References: MIME-Version: 1.0 Message-ID: <164383384623.16921.5814708160589665711.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The following commit has been merged into the x86/irq branch of tip: Commit-ID: c9df2d2677e823a110456bedd4357360b9ee2eda Gitweb: https://git.kernel.org/tip/c9df2d2677e823a110456bedd4357360b= 9ee2eda Author: Maciej W. Rozycki AuthorDate: Sun, 02 Jan 2022 23:24:41=20 Committer: Thomas Gleixner 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=20 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=20 standardised way of routing interrupts by the means of swizzling do it=20 for configurations that use a PIRQ router as well, like with APIC-based=20 setups, and use the determined corresponding topmost bridge's interrupt=20 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 Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/r/alpine.DEB.2.21.2201020158320.56863@angie.o= rcam.me.uk --- 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 =3D pirq_table; int entries =3D (rt->size - sizeof(struct irq_routing_table)) / @@ -1157,11 +1157,42 @@ static struct irq_info *pirq_get_info(struct pci_de= v *dev) return slotinfo; } =20 +/* + * 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 =3D dev; + struct irq_info *info; + u8 temp_pin =3D *pin; + u8 dpin =3D temp_pin; + + info =3D pirq_get_dev_info(dev); + while (!info && temp_dev->bus->parent) { + struct pci_dev *bridge =3D temp_dev->bus->self; + + temp_pin =3D pci_swizzle_interrupt_pin(temp_dev, temp_pin); + info =3D 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 =3D bridge; + } + *pin =3D 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 =3D 0; u32 mask; struct irq_router *r =3D &pirq_router; @@ -1169,8 +1200,8 @@ static int pcibios_lookup_irq(struct pci_dev *dev, in= t assign) char *msg =3D NULL; =20 /* 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; =20 - info =3D pirq_get_info(dev); + pin =3D dpin; + info =3D 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 =3D info->irq[pin - 1].link; mask =3D 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 &=3D pcibios_irq_mask; =20 /* Work around broken HP Pavilion Notebooks which assign USB to @@ -1238,7 +1270,7 @@ static int pcibios_lookup_irq(struct pci_dev *dev, in= t assign) newirq =3D 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); =20 /* Check if it is hardcoded */ if ((pirq & 0xf0) =3D=3D 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); =20 /* 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; =20 - info =3D pirq_get_info(dev2); + pin =3D dpin; + info =3D pirq_get_info(dev2, &pin); if (!info) continue; if (info->irq[pin - 1].link =3D=3D pirq) {