From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EC0B7C11F6D for ; Sat, 10 Jul 2021 23:52:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DB699613B5 for ; Sat, 10 Jul 2021 23:52:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233615AbhGJXz2 (ORCPT ); Sat, 10 Jul 2021 19:55:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:41052 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233711AbhGJXyc (ORCPT ); Sat, 10 Jul 2021 19:54:32 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id DEA2D613D2; Sat, 10 Jul 2021 23:51:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625961084; bh=tCUh3rEoL7t0V6Q9DxLofggK+iSzdMEzMiUzlyIwDPc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RoD8Y0c+qpsB5OKYw27avvDXSXBDajIRNRHUadxwsHRLY30xXNcn3blEiqhv0GJRO GItiSbVh4Q9OBoKVDzyf5g4iLwdgbzEeS0uB+kRp3xaijU1dC82aWQnnnrA+LLiwqr 3HY/+OFBz+fcYMiJOG4PuRFJwtauQveMzQNhm+tRLXXRPd22A+xh4OkoMgVxzEAmd2 s05uX+pTaA6C1l4NMpV2T713GRkYB99vkJ3/t+5lkG0hLKFEJDJ0rrx7WTq7u9HhDN F+AntMcgv2exX7qt23NhnPq2jMZ5gOlCXwaEXoFtiCgpPF5aaEpS6Ho86i44DMdByY mdNhABNtGPkxg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jan Kiszka , Guenter Roeck , Wim Van Sebroeck , Sasha Levin , linux-watchdog@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 13/28] watchdog: iTCO_wdt: Account for rebooting on second timeout Date: Sat, 10 Jul 2021 19:50:52 -0400 Message-Id: <20210710235107.3221840-13-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210710235107.3221840-1-sashal@kernel.org> References: <20210710235107.3221840-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org From: Jan Kiszka [ Upstream commit cb011044e34c293e139570ce5c01aed66a34345c ] This was already attempted to fix via 1fccb73011ea: If the BIOS did not enable TCO SMIs, the timer definitely needs to trigger twice in order to cause a reboot. If TCO SMIs are on, as well as SMIs in general, we can continue to assume that the BIOS will perform a reboot on the first timeout. QEMU with its ICH9 and related BIOS falls into the former category, currently taking twice the configured timeout in order to reboot the machine. For iTCO version that fall under turn_SMI_watchdog_clear_off, this is also true and was currently only addressed for v1, irrespective of the turn_SMI_watchdog_clear_off value. Signed-off-by: Jan Kiszka Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/0b8bb307-d08b-41b5-696c-305cdac6789c@siemens.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Signed-off-by: Sasha Levin --- drivers/watchdog/iTCO_wdt.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c index e707c4797f76..08e534fba1bf 100644 --- a/drivers/watchdog/iTCO_wdt.c +++ b/drivers/watchdog/iTCO_wdt.c @@ -72,6 +72,8 @@ #define TCOBASE(p) ((p)->tco_res->start) /* SMI Control and Enable Register */ #define SMI_EN(p) ((p)->smi_res->start) +#define TCO_EN (1 << 13) +#define GBL_SMI_EN (1 << 0) #define TCO_RLD(p) (TCOBASE(p) + 0x00) /* TCO Timer Reload/Curr. Value */ #define TCOv1_TMR(p) (TCOBASE(p) + 0x01) /* TCOv1 Timer Initial Value*/ @@ -344,8 +346,12 @@ static int iTCO_wdt_set_timeout(struct watchdog_device *wd_dev, unsigned int t) tmrval = seconds_to_ticks(p, t); - /* For TCO v1 the timer counts down twice before rebooting */ - if (p->iTCO_version == 1) + /* + * If TCO SMIs are off, the timer counts down twice before rebooting. + * Otherwise, the BIOS generally reboots when the SMI triggers. + */ + if (p->smi_res && + (SMI_EN(p) & (TCO_EN | GBL_SMI_EN)) != (TCO_EN | GBL_SMI_EN)) tmrval /= 2; /* from the specs: */ @@ -510,7 +516,7 @@ static int iTCO_wdt_probe(struct platform_device *pdev) * Disables TCO logic generating an SMI# */ val32 = inl(SMI_EN(p)); - val32 &= 0xffffdfff; /* Turn off SMI clearing watchdog */ + val32 &= ~TCO_EN; /* Turn off SMI clearing watchdog */ outl(val32, SMI_EN(p)); } -- 2.30.2