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=-7.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=no 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 72B8BC4338F for ; Mon, 16 Aug 2021 13:11:09 +0000 (UTC) Received: from phobos.denx.de (phobos.denx.de [85.214.62.61]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B826F60E78 for ; Mon, 16 Aug 2021 13:11:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org B826F60E78 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=nic.cz Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.denx.de Received: from h2850616.stratoserver.net (localhost [IPv6:::1]) by phobos.denx.de (Postfix) with ESMTP id EE08C82BCE; Mon, 16 Aug 2021 15:11:06 +0200 (CEST) Authentication-Results: phobos.denx.de; dmarc=pass (p=none dis=none) header.from=nic.cz Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=u-boot-bounces@lists.denx.de Authentication-Results: phobos.denx.de; dkim=pass (1024-bit key; secure) header.d=nic.cz header.i=@nic.cz header.b="Hici8YMi"; dkim-atps=neutral Received: by phobos.denx.de (Postfix, from userid 109) id C3E2982BCE; Mon, 16 Aug 2021 15:11:05 +0200 (CEST) Received: from mail.nic.cz (lists.nic.cz [IPv6:2001:1488:800:400::400]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by phobos.denx.de (Postfix) with ESMTPS id 513EF82C47 for ; Mon, 16 Aug 2021 15:11:01 +0200 (CEST) Authentication-Results: phobos.denx.de; dmarc=pass (p=none dis=none) header.from=nic.cz Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=marek.behun@nic.cz Received: from dellmb (unknown [IPv6:2001:1488:fffe:6:8747:7254:5571:3010]) by mail.nic.cz (Postfix) with ESMTPSA id F19C1140995; Mon, 16 Aug 2021 15:11:00 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=nic.cz; s=default; t=1629119461; bh=X7dMvNdPIR8XQUBea8Sg1f92bCcSmGmCp6Z0yPy2Bwk=; h=Date:From:To; b=Hici8YMiuKPpSAfODs0omF8mGFzfNsj1i/cAAqo3lDj1+XR0GXk1yqU/NneT11RgO aQayZjrBv+9vaR7HcPt2R6UPvMTR6t7YPKu0vaWmpGqZBTXDS2RrXLLuT8/fM321nP MaSZArUs+qaZTHd3Z4RTRDYMwzud3j7j5FxvKa2Q= Date: Mon, 16 Aug 2021 15:11:00 +0200 From: Marek =?UTF-8?B?QmVow7pu?= To: Stefan Roese Cc: u-boot@lists.denx.de, pali@kernel.org Subject: Re: [PATCH u-boot-mvebu 3/3] arm: mvebu: turris_omnia: disable MCU watchdog in SPL when booting over UART Message-ID: <20210816151100.0d9e7cc0@dellmb> In-Reply-To: References: <20210816122726.14506-1-marek.behun@nic.cz> <20210816122726.14506-4-marek.behun@nic.cz> <446b9f6d-70d0-04fc-ea4c-edbd876a194e@denx.de> <20210816150140.5a622211@dellmb> X-Mailer: Claws Mail 3.18.0 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.34 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" X-Virus-Scanned: clamav-milter 0.103.2 at phobos.denx.de X-Virus-Status: Clean On Mon, 16 Aug 2021 15:07:33 +0200 Stefan Roese wrote: > So the MCU watchdog is some kind of very early WD and only used until > the SoC WD is used / enabled? Yes, this is how it was first thought of for Omnia. Looking at the MCU code it seems that the watchdog can be started again after being disabled, so it could theoretically be used as a normal watchdog. The problem is that it cannot be pinged to reset the counter. It has to be stopped and started again, meaning there is a small window when it is disabled. If the system used this watchdog, this small window would make it vulnerable, so I don't think we should use it. >> Shall I resend this series with this new patch? > Yes, please do. Will do. Marek