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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 1024BC3A5A1 for ; Fri, 23 Aug 2019 03:37:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DC03F23400 for ; Fri, 23 Aug 2019 03:37:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391537AbfHWDhr (ORCPT ); Thu, 22 Aug 2019 23:37:47 -0400 Received: from mga01.intel.com ([192.55.52.88]:49107 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732546AbfHWDhq (ORCPT ); Thu, 22 Aug 2019 23:37:46 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 22 Aug 2019 20:37:46 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,419,1559545200"; d="scan'208";a="378740655" Received: from linux.intel.com ([10.54.29.200]) by fmsmga005.fm.intel.com with ESMTP; 22 Aug 2019 20:37:45 -0700 Received: from [10.226.38.55] (rtanwar-mobl.gar.corp.intel.com [10.226.38.55]) by linux.intel.com (Postfix) with ESMTP id 78D5D5803A5; Thu, 22 Aug 2019 20:37:41 -0700 (PDT) Subject: Re: [PATCH v1 1/2] x86/rtc: Add option to skip using RTC To: Andy Shevchenko Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com, tony.luck@intel.com, x86@kernel.org, a.zummo@towertech.it, alexandre.belloni@bootlin.com, robh+dt@kernel.org, mark.rutland@arm.com, linux-rtc@vger.kernel.org, devicetree@vger.kernel.org, alan@linux.intel.com, linux-kernel@vger.kernel.org, qi-ming.wu@intel.com, cheol.yong.kim@intel.com, rahul.tanwar@intel.com References: <20190822090208.GJ30120@smile.fi.intel.com> <25f6947d-7ba0-c23c-25aa-c4c4173da6b0@linux.intel.com> <20190822130429.GN30120@smile.fi.intel.com> From: "Tanwar, Rahul" Message-ID: Date: Fri, 23 Aug 2019 11:37:38 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.7.2 MIME-Version: 1.0 In-Reply-To: <20190822130429.GN30120@smile.fi.intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Andy, On 22/8/2019 9:04 PM, Andy Shevchenko wrote: > On Thu, Aug 22, 2019 at 05:26:33PM +0800, Tanwar, Rahul wrote: >> On 22/8/2019 5:02 PM, Andy Shevchenko wrote: >>> On Thu, Aug 22, 2019 at 03:44:03PM +0800, Rahul Tanwar wrote: >>>> Use a newly introduced optional "status" property of "motorola,mc146818" >>>> compatible DT node to determine if RTC is supported. Skip read/write from >>>> RTC device only when this node is present and status is "disabled". In all >>>> other cases, proceed as before. >>> Can't we rather update ->get_wallclock() and ->set_wallclock() based on this? >> >> get_wallclock() and set_wallclock() are function pointers of platform_ops >> >> which are initialized to mach_get_cmos_time() and mach_set_rtc_mmss() >> >> at init time. Since adding a new platform to override these functions is >> >> discouraged, so the only way is to modify RTC get/set functions. > Shouldn't it be platform agnostic code? > So, my point is, instead of hacking two functions, perhaps better to avoid them > at all. Sorry, i could not understand your point. The changes are platform agnostic i.e. it doesn't break existing use cases. Are you recommending to add a new platform and make changes there ? Regards, Rahul > >