From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753930AbdBUQwH (ORCPT ); Tue, 21 Feb 2017 11:52:07 -0500 Received: from foss.arm.com ([217.140.101.70]:34816 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751133AbdBUQwB (ORCPT ); Tue, 21 Feb 2017 11:52:01 -0500 Subject: Re: [PATCH/RFC 3/6] drivers: firmware: psci: Implement shallow suspend mode To: Geert Uytterhoeven References: <1487622809-25127-1-git-send-email-geert+renesas@glider.be> <1487622809-25127-4-git-send-email-geert+renesas@glider.be> <08c5dcf3-9d7c-33ff-f801-8f94f630f49b@arm.com> Cc: Sudeep Holla , Geert Uytterhoeven , Lorenzo Pieralisi , Mark Rutland , Lina Iyer , John Stultz , Thomas Gleixner , "Rafael J . Wysocki" , Len Brown , Pavel Machek , Rob Herring , Magnus Damm , "devicetree@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Linux-Renesas , Linux PM list , "linux-kernel@vger.kernel.org" From: Sudeep Holla Organization: ARM Message-ID: <016dd5fc-08c2-0084-5332-2992ab95f134@arm.com> Date: Tue, 21 Feb 2017 16:51:48 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.7.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21/02/17 16:23, Geert Uytterhoeven wrote: > Hi Sudeep, > > On Tue, Feb 21, 2017 at 11:42 AM, Sudeep Holla wrote: >> On 20/02/17 20:33, Geert Uytterhoeven wrote: >>> Enable support for "shallow" suspend mode, also known as "Standby" or >>> "Power-On Suspend". >>> >>> As secondary CPU cores are taken offline, "shallow" suspend mode saves >>> slightly more power than "s2idle", but less than "deep" suspend mode. >>> However, unlike "deep" suspend mode, "shallow" suspend mode can be used >>> regardless of the presence of support for PSCI_SYSTEM_SUSPEND, which is >>> an optional API in PSCI v1.0. >>> >>> List the available system suspend modes: >>> >>> $ cat /sys/power/mem_sleep >>> s2idle shallow [deep] >>> >>> Suspend to "shallow" mode: >>> >>> $ echo shallow > /sys/power/mem_sleep >>> $ echo mem > /sys/power/state >>> >> >> I don't have the links to such previous attempts handy, but we have > > Don't worry, I did read earlier discussions about implementing shallow mode. > In short or just to summarize in one line, just use "freeze"(a.k.a suspend-to-idle suspend mode) -- Regards, Sudeep From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sudeep Holla Subject: Re: [PATCH/RFC 3/6] drivers: firmware: psci: Implement shallow suspend mode Date: Tue, 21 Feb 2017 16:51:48 +0000 Message-ID: <016dd5fc-08c2-0084-5332-2992ab95f134@arm.com> References: <1487622809-25127-1-git-send-email-geert+renesas@glider.be> <1487622809-25127-4-git-send-email-geert+renesas@glider.be> <08c5dcf3-9d7c-33ff-f801-8f94f630f49b@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-pm-owner@vger.kernel.org To: Geert Uytterhoeven Cc: Sudeep Holla , Geert Uytterhoeven , Lorenzo Pieralisi , Mark Rutland , Lina Iyer , John Stultz , Thomas Gleixner , "Rafael J . Wysocki" , Len Brown , Pavel Machek , Rob Herring , Magnus Damm , "devicetree@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Linux-Renesas , Linux PM list , "linux-kernel@vger.kernel.org" List-Id: devicetree@vger.kernel.org On 21/02/17 16:23, Geert Uytterhoeven wrote: > Hi Sudeep, > > On Tue, Feb 21, 2017 at 11:42 AM, Sudeep Holla wrote: >> On 20/02/17 20:33, Geert Uytterhoeven wrote: >>> Enable support for "shallow" suspend mode, also known as "Standby" or >>> "Power-On Suspend". >>> >>> As secondary CPU cores are taken offline, "shallow" suspend mode saves >>> slightly more power than "s2idle", but less than "deep" suspend mode. >>> However, unlike "deep" suspend mode, "shallow" suspend mode can be used >>> regardless of the presence of support for PSCI_SYSTEM_SUSPEND, which is >>> an optional API in PSCI v1.0. >>> >>> List the available system suspend modes: >>> >>> $ cat /sys/power/mem_sleep >>> s2idle shallow [deep] >>> >>> Suspend to "shallow" mode: >>> >>> $ echo shallow > /sys/power/mem_sleep >>> $ echo mem > /sys/power/state >>> >> >> I don't have the links to such previous attempts handy, but we have > > Don't worry, I did read earlier discussions about implementing shallow mode. > In short or just to summarize in one line, just use "freeze"(a.k.a suspend-to-idle suspend mode) -- Regards, Sudeep From mboxrd@z Thu Jan 1 00:00:00 1970 From: sudeep.holla@arm.com (Sudeep Holla) Date: Tue, 21 Feb 2017 16:51:48 +0000 Subject: [PATCH/RFC 3/6] drivers: firmware: psci: Implement shallow suspend mode In-Reply-To: References: <1487622809-25127-1-git-send-email-geert+renesas@glider.be> <1487622809-25127-4-git-send-email-geert+renesas@glider.be> <08c5dcf3-9d7c-33ff-f801-8f94f630f49b@arm.com> Message-ID: <016dd5fc-08c2-0084-5332-2992ab95f134@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 21/02/17 16:23, Geert Uytterhoeven wrote: > Hi Sudeep, > > On Tue, Feb 21, 2017 at 11:42 AM, Sudeep Holla wrote: >> On 20/02/17 20:33, Geert Uytterhoeven wrote: >>> Enable support for "shallow" suspend mode, also known as "Standby" or >>> "Power-On Suspend". >>> >>> As secondary CPU cores are taken offline, "shallow" suspend mode saves >>> slightly more power than "s2idle", but less than "deep" suspend mode. >>> However, unlike "deep" suspend mode, "shallow" suspend mode can be used >>> regardless of the presence of support for PSCI_SYSTEM_SUSPEND, which is >>> an optional API in PSCI v1.0. >>> >>> List the available system suspend modes: >>> >>> $ cat /sys/power/mem_sleep >>> s2idle shallow [deep] >>> >>> Suspend to "shallow" mode: >>> >>> $ echo shallow > /sys/power/mem_sleep >>> $ echo mem > /sys/power/state >>> >> >> I don't have the links to such previous attempts handy, but we have > > Don't worry, I did read earlier discussions about implementing shallow mode. > In short or just to summarize in one line, just use "freeze"(a.k.a suspend-to-idle suspend mode) -- Regards, Sudeep