Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965041AbbHKLhS (ORCPT ); Tue, 11 Aug 2015 07:37:18 -0400 Received: from mx07-00178001.pphosted.com ([62.209.51.94]:45894 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964989AbbHKLhN (ORCPT ); Tue, 11 Aug 2015 07:37:13 -0400 Message-ID: <55C9DE57.2090105@st.com> Date: Tue, 11 Aug 2015 13:36:55 +0200 From: Maxime Coquelin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.8.0 MIME-Version: 1.0 To: Geert Uytterhoeven CC: Lee Jones , Michael Turquette , "linux-kernel@vger.kernel.org" , , Stephen Boyd , Maxime Ripard , Sascha Hauer Subject: Re: [PATCH RFC RFT 3/3] clk: introduce CLK_ENABLE_HAND_OFF flag References: <1438974570-20812-1-git-send-email-mturquette@baylibre.com> <1438974570-20812-4-git-send-email-mturquette@baylibre.com> <20150810144811.GN3249@x1> <20150810185516.2416.32293@quantum> <20150811084329.GA13374@x1> <55C9C82F.6060401@st.com> In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.201.21.241] X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.14.151,1.0.33,0.0.0000 definitions=2015-08-11_05:2015-08-11,2015-08-11,1970-01-01 signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1413 Lines: 39 Hi Geert, On 08/11/2015 12:11 PM, Geert Uytterhoeven wrote: > Hi Maxime, > > On Tue, Aug 11, 2015 at 12:02 PM, Maxime Coquelin > wrote: >> How can we pass CLK_ENABLE_HAND_OFF flag to a specific clock on STi >> platform? > Add the flag to the relevant clocks in the C code, e.g. in > clk_register_flexgen(): > > if (!strcmp(name, "clk-icn-cpu")) > init.flags |= CLK_ENABLE_HAND_OFF; The main problem I see with this proposal > >> Could we imagine having a kind of "clocks-enable-hand-off" property we could >> use in our clock controller DT node? > You can imagine doing "flex_flags |= CLK_ENABLE_HAND_OFF" in > st_of_flexgen_setup(), depending on the presence of such a property. Exactly, this is what I was thinking about. > > However, not disabling clocks is a software policy, not a hardware description, > so IMHO it doesn't belong in DT. > I disagree here because if these clocks get gated the system is dead, so I wouldn't call this a SW Policy. Moreover, I don't see how this property is different from assigned-clock-parents and assigned-clock-rates properties, which have been accepted. Thanks, Maxime -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/