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=-2.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,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 21D7FC43603 for ; Wed, 11 Dec 2019 20:28:34 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id EB3142077B for ; Wed, 11 Dec 2019 20:28:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="HBpy2Jbj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EB3142077B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=vYWxOatU0mOx/pL7gp23nmuLd9pIPUtUON/UNJ7D0Gk=; b=HBpy2Jbj/NCIdN N2HdI1lvHped36wBzPYvJw11n5qMgYucArFPXgu+ZMl7J2idBimbD3EqCFiZO0MV/OccZdOHqNpHc lskA1nlsFDC/ELUcJhcqQV3uGOCwFz2juk6JVe5nYVYpWoyeXOtpprHYh1xWm88keInv4xy324BQJ n7F/yhmVjlSPHO2KNF4dEkQOw/N4+/64J7bQRWljI8DrMWjVsGhR13yVbiCrji6hSoWbpt53b43Lw YGZVJW0z/GzIG/4FmZnb61KmZ+wfPzEdaQazmKBG0aL0Z1N6rJO0AqBuX8clGNAkBVQ+PyLKdBkS9 R9LOGrMaEY3wPm6QO1uA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1if8b3-0006eO-3i; Wed, 11 Dec 2019 20:28:33 +0000 Received: from mga01.intel.com ([192.55.52.88]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1if8az-0006dy-Ty for linux-arm-kernel@lists.infradead.org; Wed, 11 Dec 2019 20:28:31 +0000 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 11 Dec 2019 12:28:29 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,303,1571727600"; d="scan'208";a="245423821" Received: from smile.fi.intel.com (HELO smile) ([10.237.68.40]) by fmsmga002.fm.intel.com with ESMTP; 11 Dec 2019 12:28:20 -0800 Received: from andy by smile with local (Exim 4.93-RC7) (envelope-from ) id 1if8ao-0005om-8s; Wed, 11 Dec 2019 22:28:18 +0200 Date: Wed, 11 Dec 2019 22:28:18 +0200 From: Andy Shevchenko To: Jae Hyun Yoo Subject: Re: [PATCH v11 06/14] peci: Add Aspeed PECI adapter driver Message-ID: <20191211202818.GD32742@smile.fi.intel.com> References: <20191211194624.2872-1-jae.hyun.yoo@linux.intel.com> <20191211194624.2872-7-jae.hyun.yoo@linux.intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20191211194624.2872-7-jae.hyun.yoo@linux.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191211_122829_979149_F7C70843 X-CRM114-Status: GOOD ( 16.68 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Randy Dunlap , Tomer Maimon , devicetree@vger.kernel.org, Frederic Barrat , Mauro Carvalho Chehab , Lee Jones , Eric Sandeen , Lorenzo Pieralisi , Jonathan Corbet , openbmc@lists.ozlabs.org, linux-doc@vger.kernel.org, Kishon Vijay Abraham I , Joel Stanley , "Bryant G . Ly" , Uwe Kleine-Konig , David Kershner , Guenter Roeck , Wu Hao , linux-hwmon@vger.kernel.org, Jean Delvare , Arnd Bergmann , Philippe Ombredanne , Johan Hovold , Tomohiro Kusumi , Rob Herring , Thomas Gleixner , Sagar Dharia , linux-arm-kernel@lists.infradead.org, Juergen Gross , Cyrille Pitchen , Ryan Chen , Andrew Jeffery , Greg Kroah-Hartman , "Darrick J . Wong" , Stephen Boyd , Vinod Koul , Gustavo Pimentel , Andrew Morton , Robin Murphy , "David S . Miller" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Dec 11, 2019 at 11:46:16AM -0800, Jae Hyun Yoo wrote: > This commit adds Aspeed PECI adapter driver for Aspeed > AST24xx/25xx/26xx SoCs. ... > +#define ASPEED_PECI_CMD_IDLE_MASK (ASPEED_PECI_CMD_STS_MASK | \ > + ASPEED_PECI_CMD_PIN_MON) Better looking when the value completely occupies second line without touching the first. ... > +static int aspeed_peci_check_idle(struct aspeed_peci *priv) > +{ > + ulong timeout = jiffies + usecs_to_jiffies(ASPEED_PECI_IDLE_CHECK_TIMEOUT_USEC); > + u32 cmd_sts; Like in the previous patch this one has hard to read timeout loops with inefficient code. > + for (;;) { > + cmd_sts = readl(priv->base + ASPEED_PECI_CMD); > + if (!(cmd_sts & ASPEED_PECI_CMD_IDLE_MASK)) > + break; > + if (time_after(jiffies, timeout)) { This is actually main exit condition (vs. infinite loop). > + cmd_sts = readl(priv->base + ASPEED_PECI_CMD); This make no sense. If you would like to have one more iteration, just spell it explicitly. > + break; > + } > + usleep_range((ASPEED_PECI_IDLE_CHECK_INTERVAL_USEC >> 2) + 1, > + ASPEED_PECI_IDLE_CHECK_INTERVAL_USEC); > + } > + > + return !(cmd_sts & ASPEED_PECI_CMD_IDLE_MASK) ? 0 : -ETIMEDOUT; Ditto. > +} Now look at the other variant: do { ...do something... if (success) return 0; usleep(...); } while (time_before(...)); return -ETIMEDOUT; * Easy * less LOCs * guaranteed always to be at least one iteration * has explicitly spelled exit condition BUT! In this very case you may do even better if you read iopoll.h, i.e readl_poll_timeout() has this functionality embedded in the macro. -- With Best Regards, Andy Shevchenko _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel