From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Boyd Subject: Re: [PATCH v2 00/10] QCOM 8074 cpuidle driver Date: Tue, 12 Aug 2014 18:52:02 -0700 Message-ID: <53EAC4C2.70405@codeaurora.org> References: <1407872640-6732-1-git-send-email-lina.iyer@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.codeaurora.org ([198.145.11.231]:54980 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752827AbaHMBwD (ORCPT ); Tue, 12 Aug 2014 21:52:03 -0400 In-Reply-To: <1407872640-6732-1-git-send-email-lina.iyer@linaro.org> Sender: linux-arm-msm-owner@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org To: Lina Iyer Cc: daniel.lezcano@linaro.org, khilman@linaro.org, amit.kucheria@linaro.org, davidb@codeaurora.org, galak@codeaurora.org, linux-arm-msm@vger.kernel.org, msivasub@codeaurora.org On 08/12/14 12:43, Lina Iyer wrote: > This is version #2 of the patches for cpuidle driver and its dependencies. > > Changes from version #1/RFC: > > - Remove hotplug from the patch series. Will submit it seprately. > - Fix SPM drivers per the review comments > - Modify patch sequence to compile SPM drivers independent of msm-pm, so as to > allow wfi() calls to use SPM even without SoC interface driver. > > 8074 like any ARM SoC can do architectural clock gating, that helps save on > power, but not enough of leakage power. Leakage power of the SoC can be > further reduced by turning off power to the core. To aid this, every core (cpu > and L2) is accompanied by a Sub-system Power Manager (SPM), that can be > configured to indicate the low power mode, the core would be put into and the > SPM programs the peripheral h/w accordingly to enter low power and turn off the > power rail to the core. > General question before I go diving into the code, can this code use the pending generic cpuidle state bindings[1]? Last I saw those bindings looked pretty good. [1] http://lwn.net/Articles/606080/ -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation