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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4E38FC433FE for ; Thu, 2 Dec 2021 07:43:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1355855AbhLBHqu (ORCPT ); Thu, 2 Dec 2021 02:46:50 -0500 Received: from cpanel.siel.si ([46.19.9.99]:50440 "EHLO cpanel.siel.si" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345486AbhLBHqt (ORCPT ); Thu, 2 Dec 2021 02:46:49 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=norik.com; s=default; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:MIME-Version: Date:Message-ID:From:References:Cc:To:Subject:Sender:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=tBo6YAMnSGqoGlwdEydrQuSMok3rjMTScuODlnhntX8=; b=jPnrRaMDRPb/8TzJvoiYHeQg5d aaRXeZ0jx0NHqRihC0eHsrwqTiyWdEdu5pkJxjyIRDuw02XvE6lTU1ioHrwrB8dNuA9oi7H6FwLuW Q55J9GHYqVbA4OLzNGr4q6L94AZR5N5koF+s6NxJlh33w3CEcUNQxf97Wx5/6T7xcaLowH+MfH58b kEz0LdjcORRGcnwMXhAaoEUOPDBqQzJmoIuWEtPdWMMcc4VOTQSOkbm0bQO/vjRY7z6zK/40CGuJE vzY00yG6/tpX9tagP2rll5hHCOh1vE1mmKaWz81eiG/ZyXYVL/yXV+wGSDfczENcJPaOhZPHn9qY6 +zCsDZTw==; Received: from [89.212.21.243] (port=49188 helo=[192.168.69.215]) by cpanel.siel.si with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94.2) (envelope-from ) id 1msgkO-00D7S7-37; Thu, 02 Dec 2021 08:43:23 +0100 Subject: Re: [PATCH v3 2/4] watchdog: da9062: reset board on watchdog timeout To: Christoph Niedermaier , "support.opensource@diasemi.com" , "linux@roeck-us.net" , "linux-watchdog@vger.kernel.org" Cc: "wim@linux-watchdog.org" , "linux-kernel@vger.kernel.org" , "robh+dt@kernel.org" , "devicetree@vger.kernel.org" , "shawnguo@kernel.org" , "s.hauer@pengutronix.de" , "kernel@pengutronix.de" , "festevam@gmail.com" , "linux-imx@nxp.com" , "linux-arm-kernel@lists.infradead.org" References: <20211201081512.3580837-1-andrej.picej@norik.com> <20211201081512.3580837-2-andrej.picej@norik.com> <13e0b9047f114722a0b4ebb4c1d24f2b@dh-electronics.com> From: Andrej Picej Message-ID: <9298e77a-d74e-f51a-187f-830da184e67d@norik.com> Date: Thu, 2 Dec 2021 08:43:23 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: <13e0b9047f114722a0b4ebb4c1d24f2b@dh-electronics.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - cpanel.siel.si X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - norik.com X-Get-Message-Sender-Via: cpanel.siel.si: authenticated_id: andrej.picej@norik.com X-Authenticated-Sender: cpanel.siel.si: andrej.picej@norik.com X-Source: X-Source-Args: X-Source-Dir: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Christoph, On 1. 12. 21 15:11, Christoph Niedermaier wrote: > From: Andrej Picej > Sent: Wednesday, December 1, 2021 9:15 AM >> Implement a method to change watchdog timeout configuration based on DT >> binding ("dlg,wdt-sd"). There is a possibility to change the bahaviour >> of watchdog reset. Setting WATCHDOG_SD bit enables SHUTDOWN mode, and >> clearing it enables POWERDOWN mode on watchdog timeout. >> >> If no DT binding is specified the WATCHDOG_SD bit stays in default >> configuration, not breaking behaviour of devices which might depend on >> default fuse configuration. >> >> Note: This patch requires that the config register CONFIG_I is >> configured as writable in the da9062 multi function device. >> >> Signed-off-by: Andrej Picej >> --- >> Changes in v3: >> - no changes >> >> Changes in v2: >> - don't force the "reset" for all da9062-watchdog users, instead add DT >> binding where the behavior can be selected >> --- >> drivers/watchdog/da9062_wdt.c | 25 +++++++++++++++++++++++++ >> 1 file changed, 25 insertions(+) >> >> diff --git a/drivers/watchdog/da9062_wdt.c b/drivers/watchdog/da9062_wdt.c >> index f02cbd530538..e342e9e50cb1 100644 >> --- a/drivers/watchdog/da9062_wdt.c >> +++ b/drivers/watchdog/da9062_wdt.c >> @@ -85,8 +85,33 @@ static int da9062_wdt_start(struct watchdog_device *wdd) >> { >> struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); >> unsigned int selector; >> + unsigned int mask; >> + u32 val; >> int ret; >> >> + /* Configure what happens on watchdog timeout. Can be specified with >> + * "dlg,wdt-sd" dt-binding (0 -> POWERDOWN, 1 -> SHUTDOWN). >> + * If "dlg,wdt-sd" dt-binding is NOT set use the default. >> + */ >> + ret = device_property_read_u32(wdd->parent, "dlg,wdt-sd", &val); >> + if (!ret) { >> + if (val) >> + /* Use da9062's SHUTDOWN mode */ >> + mask = DA9062AA_WATCHDOG_SD_MASK; >> + else >> + /* Use da9062's POWERDOWN mode. */ >> + mask = 0x0; >> + >> + ret = regmap_update_bits(wdt->hw->regmap, >> + DA9062AA_CONFIG_I, >> + DA9062AA_WATCHDOG_SD_MASK, >> + mask); >> + >> + if (ret) >> + dev_err(wdt->hw->dev, "failed to set wdt reset mode: >> %d\n", >> + ret); >> + } >> + >> selector = da9062_wdt_timeout_to_sel(wdt->wdtdev.timeout); >> ret = da9062_wdt_update_timeout_register(wdt, selector); >> if (ret) >> -- >> 2.25.1 >> > > I have a question how to correctly restart the system after > watchdog timeout. > If I understand it correct after watchdog timeout the system > restarts only if WATCHDOG_SD (Bit 3) in register CONFIG_I is > set. > What is the difference if WATCHDOG_SD isn't set, but WAKE_UP > (Bit 2) in register CONTROL_F is set? From outside on my > system I observe the same behavior. After watchdog timeout > my system restarts. So where are the differences? > It would be nice if you could answer this question, as you > certainly know this chip very well. To be honest I don't really know the chip that well, I'm just trying to add this feature and hopefully help others if they run into the same problem. I think @Adam will be more helpful here. But from quick look at da9062 datasheet, mainly chapter "8.8 Power Modes" I see next main differences: - setting WATCHDOG_SD enables SHUTDOWN sequence when the watchdog timeout is triggered. This puts the chip (da9062) in RESET mode. Taken from DA9062 datasheet: > In RESET mode, the internal supplies, and LDO1 (if configured as an always-on supply) are enabled. > All other DA9062 supplies are disabled. > DA9062 is in RESET mode whenever a complete application shutdown is required > The DA9062’s register configuration will be re-loaded from OTP when leaving the RESET mode - if you set the WAKE_UP bit than the chip enters POWERDOWN mode on watchdog timeout. I understand the POWERDOWN mode as a not that "deep" mode as a RESET mode Device will go from RESET mode to POWERDOWN mode in the sequence of powering-up. The above explanation is just my understanding after quick look, @Adam please correct me if I'm talking nonsense. Please have a look at the DA9062 datasheet for more information. Sorry, that I can't be more helpful here. Best regards, Andrej