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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A83D4C433F5 for ; Tue, 7 Dec 2021 15:31:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:In-Reply-To:References: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=bpmUQmfQSxJZOa7X5+xtnVxmGXNHxzfyEaplRkZ8zo0=; b=yYCrfPXm/TLHsv 7MUnEpjQeCsCRz9+e7lDaYApCyviJTACOR9O039iudu6n6HQS1p6vSReMkq8/78oSU2H6H8CU2IiP HzdMrrNIZ20V9YEbA9jIBF5rzt+Mvl/V1t4Va2CTgNLXSpQ2DpNv+l66FOar7jxO5mbhfojaDHG30 lQpxIT36EbUU3L7vRNmr31Btqy5JQSS8LVy67OyO0gpP+6YvkgmGoFTRawv/XG/QXYnKtS6h7AgxX r0X8SIlgB7Ze5Uyg9Si/NBgXX2kVkpK+OvhZt+KWZWLjanXoNFxdo2dZ1Yi/TgH3emUelLAA+NRPi MWWe+X20nUpjrAZ0ka+A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mucP4-009DnA-5s; Tue, 07 Dec 2021 15:29:15 +0000 Received: from mx4.securetransport.de ([178.254.6.145]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mucEU-0099z6-HS for linux-arm-kernel@lists.infradead.org; Tue, 07 Dec 2021 15:18:20 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dh-electronics.com; s=dhelectronicscom; t=1638890281; bh=Qud1GCpToFBPlsOqHHBPwhegVKj3nR+Sh0LtzexoC/0=; h=From:To:CC:Subject:Date:References:In-Reply-To:From; b=ZA9xxlb44fN7KElaPDxqrIj1/g2qdiK2jIxRpfCkM3Tf/Tp2hnDJ1+ny2eKQjbupB snIJlPqRIKv2Dg6hXwZnwj3QQLFE0se2pfOP/5PBpgfMVLqwdtKR5dZY1kAG3sh8Mu /bZtlCQoE1k66VvYY7deNTj6/PhPuGvOuRGjW2uRtzphRnzQrkCKQI7COJUc4JfJYH P9wE7TJH3z2tUlqPOZ8yea16nA4UrXsflmPxp1PtiJJaQk16jVaszAbyOoBXZJ83Ep QFkNWs4PxBrhXwr99LWY4rnuI1PlabgILsiMZYO1UJHXb6c1OfPyLq2uVlF9JAC3Fe QvwG4OmyiKhMw== X-secureTransport-forwarded: yes From: Christoph Niedermaier Complaints-To: abuse@cubewerk.de To: Adam Thomson , Andrej Picej , "linux-arm-kernel@lists.infradead.org" CC: Support Opensource , Wim Van Sebroeck , "linux-watchdog@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Guenter Roeck Subject: RE: [RFC PATCH] watchdog: da9062: Correct the timeout values Thread-Topic: [RFC PATCH] watchdog: da9062: Correct the timeout values Thread-Index: AQHX6GQONgXT05Iq6ke/N4Kseos6o6wg6rAAgAATvjCABAXqAIAAE0gQgACGB4CAARFsYA== Date: Tue, 7 Dec 2021 15:17:51 +0000 Message-ID: <1756f4eccb5b4106a232a6bd7a8553c8@dh-electronics.com> References: <20211203163539.91870-1-cniedermaier@dh-electronics.com> <4bfb6ab512cd45ee81c55361525987b7@dh-electronics.com> <46136729bb564aa6b9f332fa584b2575@dh-electronics.com> In-Reply-To: Accept-Language: de-DE, en-US Content-Language: de-DE X-MS-Has-Attach: X-MS-TNEF-Correlator: MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211207_071818_905020_70E2EAF1 X-CRM114-Status: GOOD ( 20.90 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Adam Thomson Sent: Monday, December 6, 2021 5:38 PM >> Thanks anyway, so now I know it must be >> problem with my DA9061 chip. >> >> @Adam >> Where can it come from? >> Can you give we a hint what to check? > > I've spoken internally and have been informed that this is down to the fact that > DA9061 runs only from an internal oscillator which may be slower. The indication > is that the values for TWDSCALE describe the window where if a kick/ping occurs > within that period then the watchdog is guaranteed *not* to timeout. The actual > timeout would be at some point after the selected timeout period, assuming no > ping/kick occurred. > > Table 8 in the datasheet specifies a minimum watchdog timeout of 2.5s (tWDMAX) > under specific operating conditions, so if the minimum 2s window was chosen > (TWDSCALE = 1) then earliest the watchdog would actually timeout, following a > ping, is 2.5s, assuming the conditions matched those described. > > If you have further questions it probably makes sense to contact Dialog/Renesas > support as they will be able to provide more detailed info on this. So a DA9061 runs only from an internal oscillator, whereas a DA9062 can run on either an internal or an external oscillator. So this means that the DA9061 timeout values are differ from the DA9062 with an external oscillator not only on my device but on all DA9061 devices. This are the values (in seconds) in comparison: DA9062 (from driver): 0 2 4 8 16 32 65 131 DA9061 (measured): 0 3 6 12 25 51 102 204 ================================================= Difference: 0 +1 +2 +4 +9 +19 +37 +73 In my opinion, the differences in the higher values are very huge. If I expect that the watchdog triggers and I have to wait more than a minute for that to happen I ask myself is there something wrong. @Andrej I guess, you are using an external oscillator, aren't you? @Adam Is there a way to check in the driver which oscillator is in use? @Maintainers Is in the driver a need to distinguish between an external and an internal oscillator to get the timeout values more accurate? Best regards Christoph _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel