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=-2.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,FROM_EXCESS_BASE64,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_NEOMUTT autolearn=ham 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 EB9B1C43381 for ; Thu, 21 Mar 2019 23:11:00 +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 B9AAE218D3 for ; Thu, 21 Mar 2019 23:11:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="l6NeJYGa" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B9AAE218D3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=collabora.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=uuV78ru9rasHaz/A2NerZR+JokdxYfBfEbHfp3KNdJY=; b=l6NeJYGaNQ38oJ 3v9bZkh7Yva1f39LSUhEh2MI4hpluJydzMmCfLsWj5042/nrJXDzonKjlUNU07tJP5Xy3BvYp+yvB g0eISPvB42bv649I7cYT0LpxHAMOtUwstSAmqW98XijAAqSXCootPHxCu/r0nc0kv3niVHeiKgMWC NZ2Do3Gq2KBq2L/Q+vwTriBa3B3VoegAzQcofO7hiL2PQQf8d+wWYZslDI07yhoxLJ2ATchTCgdk4 9nMT+X6lym7J6xt5zsV0f55LYRxPfYSpjkZtCr66EKBTOthSRyNtmR3dJYCAmgOcNIiZyl1Ej+TNr 4PFEccCJZ5icMTQDjjkA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h76pr-0002Ez-Ly; Thu, 21 Mar 2019 23:10:55 +0000 Received: from bhuna.collabora.co.uk ([46.235.227.227]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1h76po-0002Dq-2O; Thu, 21 Mar 2019 23:10:53 +0000 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: gportay) with ESMTPSA id DC14228198C Date: Thu, 21 Mar 2019 19:10:55 -0400 From: =?utf-8?B?R2HDq2w=?= PORTAY To: Matthias Kaehlcke Subject: Re: [PATCH v2 3/5] devfreq: rk3399_dmc: Pass ODT and auto power down parameters to TF-A. Message-ID: <20190321231055.j7z23f3k3rcngq4u@archlinux.localdomain> References: <20190319181323.22804-1-gael.portay@collabora.com> <20190319181323.22804-4-gael.portay@collabora.com> <20190320003352.GN112750@google.com> <20190320215013.43zgvyn5frnb3yud@archlinux.localdomain> <20190320220223.GP112750@google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190320220223.GP112750@google.com> User-Agent: NeoMutt/20180716 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190321_161052_379394_4C285337 X-CRM114-Status: GOOD ( 22.70 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , devicetree@vger.kernel.org, Derek Basehore , Heiko Stuebner , linux-pm@vger.kernel.org, Brian Norris , Douglas Anderson , linux-kernel@vger.kernel.org, Chanwoo Choi , Kyungmin Park , Rob Herring , Klaus Goger , MyungJoo Ham , Enric Balletbo i Serra , linux-rockchip@lists.infradead.org, Randy Li , kernel@collabora.com, linux-arm-kernel@lists.infradead.org, Lin Huang Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Matthias, On Wed, Mar 20, 2019 at 03:02:23PM -0700, Matthias Kaehlcke wrote: > Hi Ga=EBl, > = > On Wed, Mar 20, 2019 at 05:50:13PM -0400, Ga=EBl PORTAY wrote: > > Hi Matthias, > > = > > On Tue, Mar 19, 2019 at 05:33:52PM -0700, Matthias Kaehlcke wrote: > > > ... > > > > @@ -95,6 +103,19 @@ static int rk3399_dmcfreq_target(struct device = *dev, unsigned long *freq, > > > > = > > > > mutex_lock(&dmcfreq->lock); > > > > = > > > > + if (target_rate >=3D dmcfreq->odt_dis_freq) > > > > + odt_enable =3D true; > > > > + > > > > + /* > > > > + * This makes a SMC call to the TF-A to set the DDR PD (power-dow= n) > > > > + * timings and to enable or disable the ODT (on-die termination) > > > > + * resistors. > > > > + */ > > > > + arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, dmcfreq->odt_pd_arg0, > > > > + dmcfreq->odt_pd_arg1, > > > > + ROCKCHIP_SIP_CONFIG_DRAM_SET_ODT_PD, > > > > + odt_enable, 0, 0, 0, &res); > > > = > > > Is it necessary/desirable to make this call for every frequency > > > change? IIUC it should be only needed when odt_enable changes and the > > > driver could track the state. If the DDR frequency doesn't change too > > > often and the overhead of the call is small it shouldn't be really > > > important though. > > > > > = > > I will test your solution first to make sure there is no regression to > > run that call for frequency change only. > = Oops, I wanted to say when odt_enable changes since last call. > If there is no frequency change the function returns at the > beginning. My suggestion was to only do the call when 'odt_enable' > changes, i.e. when a change (up or down) passes the 'odt_dis_freq' > threshold. > = So, for a reason that I ignore, if we try to save unecessary calls to ROCKCHIP_SIP_CONFIG_DRAM_SET_ODT_PD (odt_enable has not changed since last call), we get stalled in the call to ROCKCHIP_SIP_CONFIG_SET_RAGE that follows. The function arm_smccc_smc never returns and the device hard hang. Thanks to your remark, I have also fixed an issue with the odt_dis_freq value. Its value is initialized to 0 in the probe function. Thus the odt_enable is always true (target_rate > 0). I moved its initialization after the timings are parsed from the device-tree; its value is now none zero (333000000 in my case). > > Also, the call takes around 300us. > = > Thanks for the info! > = > Matthias > = > _______________________________________________ > Linux-rockchip mailing list > Linux-rockchip@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-rockchip Ga=EBl _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel