From patchwork Sun Nov 13 17:34:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Mateusz_Jo=C5=84czyk?= X-Patchwork-Id: 624499 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 B2781C433FE for ; Sun, 13 Nov 2022 17:35:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234105AbiKMRfX (ORCPT ); Sun, 13 Nov 2022 12:35:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46828 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233522AbiKMRfW (ORCPT ); Sun, 13 Nov 2022 12:35:22 -0500 Received: from mx-out.tlen.pl (mx-out.tlen.pl [193.222.135.158]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E7605FCE2 for ; Sun, 13 Nov 2022 09:35:19 -0800 (PST) Received: (wp-smtpd smtp.tlen.pl 24814 invoked from network); 13 Nov 2022 18:35:15 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=o2.pl; s=1024a; t=1668360915; bh=JOXzz5c4GDKUxSgs3Q0u7I+VwUW/4AZN5La4/sOMeOQ=; h=From:To:Cc:Subject; b=WC0xbcvYZ6vqfsxdP8OIhr2JqKrJ2gNa4huYRDw8R8qw+dA/sPBxOkNr21kWlSWeC RlpMOPzL9TD99IY8XIMT1YIdNmTgEGdNTu9+vo6YrqxDys183yNa89aILJanTZMbIF oavukyRWbzlUoQ50E+jJoW/Q7neUMThlHmKMXlXw= Received: from aaey149.neoplus.adsl.tpnet.pl (HELO localhost.localdomain) (mat.jonczyk@o2.pl@[83.4.128.149]) (envelope-sender ) by smtp.tlen.pl (WP-SMTPD) with SMTP for ; 13 Nov 2022 18:35:15 +0100 From: =?utf-8?q?Mateusz_Jo=C5=84czyk?= To: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org, linux-i2c@vger.kernel.org Cc: =?utf-8?q?Mateusz_Jo=C5=84czyk?= , Bjorn Helgaas , "Rafael J. Wysocki" , Len Brown , Borislav Petkov , Jean Delvare Subject: [PATCH v2] acpi,pci: warn about duplicate IRQ routing entries returned from _PRT Date: Sun, 13 Nov 2022 18:34:42 +0100 Message-Id: <20221113173442.5770-1-mat.jonczyk@o2.pl> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221112200927.7255-1-mat.jonczyk@o2.pl> References: <20221112200927.7255-1-mat.jonczyk@o2.pl> MIME-Version: 1.0 X-WP-MailID: 934e56db77df8ec1dea79e941e558262 X-WP-AV: skaner antywirusowy Poczty o2 X-WP-SPAM: NO 0000000 [kSOl] Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org On some platforms, the ACPI _PRT function returns duplicate interrupt routing entries. Linux uses the first matching entry, but sometimes the second matching entry contains the correct interrupt vector. Print a warning to dmesg if duplicate interrupt routing entries are present, so that we could check how many models are affected. This happens on a Dell Latitude E6500 laptop with the i2c-i801 Intel SMBus controller. This controller was nonfunctional unless its interrupt usage was disabled (using the "disable_features=0x10" module parameter). After investigation, it turned out that the driver was using an incorrect interrupt vector: in lspci output for this device there was: Interrupt: pin B routed to IRQ 19 but after running i2cdetect (without using any i2c-i801 module parameters) the following was logged to dmesg: [...] i801_smbus 0000:00:1f.3: Timeout waiting for interrupt! i801_smbus 0000:00:1f.3: Transaction timeout i801_smbus 0000:00:1f.3: Timeout waiting for interrupt! i801_smbus 0000:00:1f.3: Transaction timeout irq 17: nobody cared (try booting with the "irqpoll" option) Existence of duplicate entries in a table returned by the _PRT method was confirmed by disassembling the ACPI DSDT table. Signed-off-by: Mateusz Jończyk Cc: Bjorn Helgaas Cc: "Rafael J. Wysocki" Cc: Len Brown Cc: Borislav Petkov Cc: Jean Delvare Reviewed-by: Jean Delvare Tested-by: Jean Delvare --- v2: - add a newline at the end of the kernel log message, - replace: "if (match == NULL)" -> "if (!match)" - patch description tweaks. Tested on two computers, including the affected Dell Latitude E6500 laptop. drivers/acpi/pci_irq.c | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) base-commit: f0c4d9fc9cc9462659728d168387191387e903cc diff --git a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c index 08e15774fb9f..a4e41b7b71ed 100644 --- a/drivers/acpi/pci_irq.c +++ b/drivers/acpi/pci_irq.c @@ -203,6 +203,8 @@ static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev, struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; struct acpi_pci_routing_table *entry; acpi_handle handle = NULL; + struct acpi_prt_entry *match = NULL; + const char *match_int_source = NULL; if (dev->bus->bridge) handle = ACPI_HANDLE(dev->bus->bridge); @@ -219,13 +221,30 @@ static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev, entry = buffer.pointer; while (entry && (entry->length > 0)) { - if (!acpi_pci_irq_check_entry(handle, dev, pin, - entry, entry_ptr)) - break; + struct acpi_prt_entry *curr; + + if (!acpi_pci_irq_check_entry(handle, dev, pin, entry, &curr)) { + if (!match) { + match = curr; + match_int_source = entry->source; + } else { + pr_warn(FW_BUG + "ACPI _PRT returned duplicate IRQ routing entries for device " + "%04x:%02x:%02x[INT%c]: %s[%d] and %s[%d].\n", + curr->id.segment, curr->id.bus, curr->id.device, + pin_name(curr->pin), + match_int_source, match->index, + entry->source, curr->index); + // we use the first matching entry nonetheless + } + } + entry = (struct acpi_pci_routing_table *) ((unsigned long)entry + entry->length); } + *entry_ptr = match; + kfree(buffer.pointer); return 0; }