From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965451Ab3HHOhF (ORCPT ); Thu, 8 Aug 2013 10:37:05 -0400 Received: from mail-ob0-f178.google.com ([209.85.214.178]:47946 "EHLO mail-ob0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965243Ab3HHOhC (ORCPT ); Thu, 8 Aug 2013 10:37:02 -0400 MIME-Version: 1.0 In-Reply-To: <1375971749.4276.61.camel@weser.hi.pengutronix.de> References: <52028719.8070908@wwwdotorg.org> <52029811.9080704@wwwdotorg.org> <1375970318.4276.52.camel@weser.hi.pengutronix.de> <1375971749.4276.61.camel@weser.hi.pengutronix.de> Date: Thu, 8 Aug 2013 20:07:01 +0530 Message-ID: Subject: Re: [PATCH 2/6] ARM: Tegra: Add CPU's OPPs for using cpufreq-cpu0 driver From: Viresh Kumar To: Lucas Stach Cc: Stephen Warren , Mark Rutland , "devicetree@vger.kernel.org" , linaro-kernel@lists.linaro.org, swarren@nvidia.com, Ian Campbell , Pawel Moll , linux-pm@vger.kernel.org, patches@linaro.org, linux-kernel@vger.kernel.org, cpufreq@vger.kernel.org, rjw@sisk.pl, Rob Herring , mturquette@linaro.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8 August 2013 19:52, Lucas Stach wrote: > You can certainly define the mapping table in DT where a specialized > Tegra cpufreq driver could read it in and then map frequency to voltage. > But that's a runtime decision, as Speedo and process ID are fuse values > and can not be represented in DT. > The problem with this is that the hardware description now associates > voltages with certain frequencies and even if they are not used by the > Linux driver they are plain wrong. Hmm. I understand. Then we probably need mach-tegra/opp.c to call opp_add() for all such OPPs.. Neither DT nor cpufreq driver are the right place for this. From mboxrd@z Thu Jan 1 00:00:00 1970 From: viresh.kumar@linaro.org (Viresh Kumar) Date: Thu, 8 Aug 2013 20:07:01 +0530 Subject: [PATCH 2/6] ARM: Tegra: Add CPU's OPPs for using cpufreq-cpu0 driver In-Reply-To: <1375971749.4276.61.camel@weser.hi.pengutronix.de> References: <52028719.8070908@wwwdotorg.org> <52029811.9080704@wwwdotorg.org> <1375970318.4276.52.camel@weser.hi.pengutronix.de> <1375971749.4276.61.camel@weser.hi.pengutronix.de> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 8 August 2013 19:52, Lucas Stach wrote: > You can certainly define the mapping table in DT where a specialized > Tegra cpufreq driver could read it in and then map frequency to voltage. > But that's a runtime decision, as Speedo and process ID are fuse values > and can not be represented in DT. > The problem with this is that the hardware description now associates > voltages with certain frequencies and even if they are not used by the > Linux driver they are plain wrong. Hmm. I understand. Then we probably need mach-tegra/opp.c to call opp_add() for all such OPPs.. Neither DT nor cpufreq driver are the right place for this.