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=-5.8 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 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 772ADC4361A for ; Fri, 4 Dec 2020 14:09:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 46CB122ADC for ; Fri, 4 Dec 2020 14:09:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388188AbgLDOJE (ORCPT ); Fri, 4 Dec 2020 09:09:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34166 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387781AbgLDOJD (ORCPT ); Fri, 4 Dec 2020 09:09:03 -0500 Received: from mail-qv1-xf41.google.com (mail-qv1-xf41.google.com [IPv6:2607:f8b0:4864:20::f41]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F345BC061A4F for ; Fri, 4 Dec 2020 06:08:22 -0800 (PST) Received: by mail-qv1-xf41.google.com with SMTP id 62so2759978qva.11 for ; Fri, 04 Dec 2020 06:08:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=YqXEsirEh9eW1VieGHrEu+QlOdgfjHIxDQpQJ3ZI1GQ=; b=DPaWF+yuM+abHWkSEYzIkGbG1X9C5nWRMqwqGsjVNKBOJ5Mev2u4CyIsRihFZaouda Xshhb+mFTlVQS+EZJT7mTRyRcMy5eGQLGYJT/txdBMgiSlL3t2F1G4DmPneafNsuCgkt QKtR/RClMRZDqiOHJd5qW74+iYZ1MQvjVJtJpNjMEvtpO4+9/GQrTTNFB+D+OfEG+2mQ xK6Q5JWuu9NzOhFZWJELZ7FYaJqiZpkuWwtL4ICswr6IRW+AuPWpuV2GykIwQHF2SueD TtnBa860pGMhACWpqHCwKgezk4pEPUAGKvhQVTz3baGPTTErwjY+fvjG4rEukkZIr1hN drLg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=YqXEsirEh9eW1VieGHrEu+QlOdgfjHIxDQpQJ3ZI1GQ=; b=BufzeddWjvYaoJUlOK3Y1mKSbgAx1G9KEw9swd0A7dtJ6CBjm1xX0n7DmVqbeZo2GW u62rU8hvGGnEteUL+edxbACIdcpRuqYK57J7mnQcmCxGNerGkIm50ctedg58zXQf8qeR uhCX6JOYq/MUrLaVFXTIzVVTza8QlwzPMpNoUg+A2tvEVpqbX07XkUkyZbWx/harDnKs EUZ5hzi3PLEoMJiCivcqku5ow0uAjH4GRt4muSFIO9HOyl9DMeynYzG70obPuc0eFvqz ltCkmD8qmvi7vToqTfcY3KY7ZC+8yP9h86PfXRw/ouYgTAd6XXAa1mqHCjn6ye89qCau ROWA== X-Gm-Message-State: AOAM5332ji0u5+okKm+N1OYJ/YUN9F6WrWVOctrS1E/rWiTj0qEoFVyL NHOb5r729V4qSh5tg/3WAMrULLOfs1fR6Q== X-Google-Smtp-Source: ABdhPJwNYN3wZEVkLRcCz859RCC5SVfMWP4iSwbgNtFU+yM6gv1YTpTw/ichnblG5iK5AJgxJ9fd0w== X-Received: by 2002:a0c:e0c9:: with SMTP id x9mr5318505qvk.56.1607090902137; Fri, 04 Dec 2020 06:08:22 -0800 (PST) Received: from ziepe.ca ([206.223.160.26]) by smtp.gmail.com with ESMTPSA id q28sm5022865qkn.39.2020.12.04.06.08.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Dec 2020 06:08:20 -0800 (PST) Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1klBkx-005s5c-Kz; Fri, 04 Dec 2020 10:08:19 -0400 Date: Fri, 4 Dec 2020 10:08:19 -0400 From: Jason Gunthorpe To: Thomas Gleixner Cc: Alexandre Belloni , Miroslav Lichvar , linux-kernel@vger.kernel.org, John Stultz , Prarit Bhargava , Alessandro Zummo , linux-rtc@vger.kernel.org, Peter Zijlstra Subject: Re: [PATCH] rtc: adapt allowed RTC update error Message-ID: <20201204140819.GX5487@ziepe.ca> References: <20201202205418.GN5487@ziepe.ca> <874kl3eu8p.fsf@nanos.tec.linutronix.de> <87zh2vd72z.fsf@nanos.tec.linutronix.de> <20201203021047.GG3544@piout.net> <87pn3qdhli.fsf@nanos.tec.linutronix.de> <20201203161622.GA1317829@ziepe.ca> <87zh2ubny2.fsf@nanos.tec.linutronix.de> <87wnxybmqx.fsf@nanos.tec.linutronix.de> <20201203223646.GA1335797@ziepe.ca> <877dpxbu66.fsf@nanos.tec.linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <877dpxbu66.fsf@nanos.tec.linutronix.de> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 04, 2020 at 02:02:57PM +0100, Thomas Gleixner wrote: > No magic sign calculation required if you look at it from the actual > timeline and account the time between write and next second increment > correctly. Yes, it is equivalent to break things into two values, and does look to be more understandable as one can read at least one of the values from a datasheet and the other could be estimated by timing a read clock Jason