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,UNPARSEABLE_RELAY,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 BC930CA9EA0 for ; Fri, 18 Oct 2019 09:04:26 +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 881F82064B for ; Fri, 18 Oct 2019 09:04:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Cl+X+bBA" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 881F82064B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=mediatek.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:MIME-Version:References:In-Reply-To: Date:To:From:Subject:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=/bJvzAomtoeRLDPJhKc4KG9schGTNpVz0lJpa2S6298=; b=Cl+X+bBAdr+Doy wbN1gAwVn24WNuso7qhApljDJ5mE5I6JRveo/PTOJlCoKesq1GfcOMe65bVT1AWRl659ma85s154e +RaE6FIZst0RV1b/Ux7XRX3zrv7CZt5IwxS4rt9U3wciOUe2q3tZ+y+B791/YH4zZGJ8HECTq27aD pPfeLW/xZVFCbszPHj8U2LegvXZOlSYv3/hKl4rHcXW3uJ2vOpFI/akdQvLBVsghlxyZEDoFEBFOW yjoHyjG9O+dtw4gUL8ffc+TkCDHbo4pW2KmtWkRCz2qx0nUNTgt0jRWP3Ty8f9qXCf0Wpj2w/Igl4 9CUaA2sGmNp/lC8eLy/Q==; 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 1iLOBO-0004U9-2W; Fri, 18 Oct 2019 09:04:26 +0000 Received: from mailgw02.mediatek.com ([216.200.240.185]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iLOBK-0004Sw-5F; Fri, 18 Oct 2019 09:04:23 +0000 X-UUID: 49d88b99c4974acbb4cb4873a1345165-20191018 X-UUID: 49d88b99c4974acbb4cb4873a1345165-20191018 Received: from mtkcas66.mediatek.inc [(172.29.193.44)] by mailgw02.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLS) with ESMTP id 403607067; Fri, 18 Oct 2019 01:03:36 -0800 Received: from MTKMBS01N1.mediatek.inc (172.21.101.68) by MTKMBS62N2.mediatek.inc (172.29.193.42) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Fri, 18 Oct 2019 02:03:50 -0700 Received: from mtkcas09.mediatek.inc (172.21.101.178) by mtkmbs01n1.mediatek.inc (172.21.101.68) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Fri, 18 Oct 2019 17:03:49 +0800 Received: from [172.21.77.4] (172.21.77.4) by mtkcas09.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Fri, 18 Oct 2019 17:03:50 +0800 Message-ID: <1571389431.27207.4.camel@mtksdaap41> Subject: Re: [v4, 7/8] cpufreq: mediatek: add opp notification for SVS support From: andrew-sh.cheng To: Viresh Kumar Date: Fri, 18 Oct 2019 17:03:51 +0800 In-Reply-To: <20191017063102.4jirlphdxdydl2bm@vireshk-i7> References: <1565703113-31479-1-git-send-email-andrew-sh.cheng@mediatek.com> <1565703113-31479-8-git-send-email-andrew-sh.cheng@mediatek.com> <20190820033927.72muldasu4xd6wb7@vireshk-i7> <1571193828.22071.5.camel@mtksdaap41> <20191017063102.4jirlphdxdydl2bm@vireshk-i7> X-Mailer: Evolution 3.10.4-0ubuntu2 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191018_020422_203232_AED68D74 X-CRM114-Status: GOOD ( 12.38 ) 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 , Nishanth Menon , srv_heupstream , "linux-pm@vger.kernel.org" , Stephen Boyd , "Rafael J. Wysocki" , "linux-kernel@vger.kernel.org" , Rob Herring , Chanwoo Choi , Kyungmin Park , MyungJoo Ham , "linux-mediatek@lists.infradead.org" , "linux-arm-kernel@lists.infradead.org" , Matthias Brugger , Fan Chen =?UTF-8?Q?=28=E9=99=B3=E5=87=A1=29?= , "devicetree@vger.kernel.org" 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 Thu, 2019-10-17 at 12:01 +0530, Viresh Kumar wrote: > On 16-10-19, 10:43, andrew-sh.cheng wrote: > > This is due to SVS feature need to fix Vproc for calibration. > > When SVS calibration, it want to disable all opp items, except one with > > voltae 1.0V. (SVS will change the voltage field of that opp item, if the > > corresponding voltage is not 1.0V) > > In this way, SVS can make sure there is no other module, include > > thermal, will change Vproc by DVFS driver. > > After SVS calibration done, SVS will enable those disabled opp items > > back. > > But why is this required to be done this way ? Why can't we just update the > voltages without doing this disable/enable dance ? > This is because some opp items need voltage larger than 1.0V. We cannot update the voltage to 1.0V. If we don't disable these opp items, and DVFS policy want to set these high frequencies, dvfs driver will set higher voltage to Vproc and SVS calibration will be fail. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel