From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751467AbdBWP66 (ORCPT ); Thu, 23 Feb 2017 10:58:58 -0500 Received: from foss.arm.com ([217.140.101.70]:56274 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751406AbdBWP6z (ORCPT ); Thu, 23 Feb 2017 10:58:55 -0500 Subject: Re: [PATCH/RFC 0/6] PSCI: Fix non-PMIC wake-up if SYSTEM_SUSPEND cuts power To: Geert Uytterhoeven References: <1487622809-25127-1-git-send-email-geert+renesas@glider.be> <94167d3a-e005-3af0-d290-a1086684d570@arm.com> <3c8b3f2d-8604-f999-4208-a82f171b64f2@arm.com> <1975396.x0czmkNPOW@aspire.rjw.lan> <35840771-e16f-d6fe-3a89-1b3f51f4a8f3@arm.com> Cc: Sudeep Holla , "Rafael J. Wysocki" , Geert Uytterhoeven , Lorenzo Pieralisi , Mark Rutland , Lina Iyer , John Stultz , Thomas Gleixner , 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: Date: Thu, 23 Feb 2017 15:58:31 +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 Hi Geert, On 23/02/17 15:34, Geert Uytterhoeven wrote: > Hi Sudeep, > > On Thu, Feb 23, 2017 at 4:26 PM, Geert Uytterhoeven > wrote: >> On Wed, Feb 22, 2017 at 3:32 PM, Sudeep Holla wrote: >>> On 22/02/17 13:38, Geert Uytterhoeven wrote: >>>> On Wed, Feb 22, 2017 at 12:03 PM, Sudeep Holla wrote: >>>> 4. Patch 3/6 adds a new "shallow" state, as it allows to save more >>>> power (the difference may be due to suboptimal cpuidle platform support on R-Car Gen3, though), >>> >>> Why can't you do that in s2idle mode. Please give me the difference >>> between your shallow state and s2idle state, not just power numbers >>> but the actual state of CPUs and the devices in the system. >> >> From the Linux side, there's not much difference, except that the secondary >> CPU cores are disabled. As that is handled by PSCI, the difference may be >> in the PSCI implementation. I will have to check that... >> >> On these SoCs, the individual CPU cores and the SCU/L2 are in separate >> (nested) power areas. Perhaps these power areas are turned off when >> disabling the CPU cores, but not when suspending them. > > BTW, I don't care much about the extra state. > Then stop caring about extra power usage too ;). Seriously this is not a valid argument. >>>> E.g. on non-PSCI platforms with an Ethernet driver that supports >>>> Wake-on-LAN, I can do: >>>> >>>> ethtool -s eth0 wol g >>>> echo mem > /sys/power/state >>>> >>>> and be sure that the system can be woken up by sending a WoL MagicPacket. >>> >>> Still possible with s2idle if CPU_SUSPEND is correctly implemented by >>> the platform. >> >> Sure. But not automatic, as it needs fiddling with mem_sleep. > > I do care about this, as it affects user experience. > Again when you have both "deep" and "standby" suspend states as per your patch set, user has to choose one. No escape from that. -- Regards, Sudeep From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sudeep Holla Subject: Re: [PATCH/RFC 0/6] PSCI: Fix non-PMIC wake-up if SYSTEM_SUSPEND cuts power Date: Thu, 23 Feb 2017 15:58:31 +0000 Message-ID: References: <1487622809-25127-1-git-send-email-geert+renesas@glider.be> <94167d3a-e005-3af0-d290-a1086684d570@arm.com> <3c8b3f2d-8604-f999-4208-a82f171b64f2@arm.com> <1975396.x0czmkNPOW@aspire.rjw.lan> <35840771-e16f-d6fe-3a89-1b3f51f4a8f3@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-renesas-soc-owner@vger.kernel.org To: Geert Uytterhoeven Cc: Sudeep Holla , "Rafael J. Wysocki" , Geert Uytterhoeven , Lorenzo Pieralisi , Mark Rutland , Lina Iyer , John Stultz , Thomas Gleixner , 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 Hi Geert, On 23/02/17 15:34, Geert Uytterhoeven wrote: > Hi Sudeep, > > On Thu, Feb 23, 2017 at 4:26 PM, Geert Uytterhoeven > wrote: >> On Wed, Feb 22, 2017 at 3:32 PM, Sudeep Holla wrote: >>> On 22/02/17 13:38, Geert Uytterhoeven wrote: >>>> On Wed, Feb 22, 2017 at 12:03 PM, Sudeep Holla wrote: >>>> 4. Patch 3/6 adds a new "shallow" state, as it allows to save more >>>> power (the difference may be due to suboptimal cpuidle platform support on R-Car Gen3, though), >>> >>> Why can't you do that in s2idle mode. Please give me the difference >>> between your shallow state and s2idle state, not just power numbers >>> but the actual state of CPUs and the devices in the system. >> >> From the Linux side, there's not much difference, except that the secondary >> CPU cores are disabled. As that is handled by PSCI, the difference may be >> in the PSCI implementation. I will have to check that... >> >> On these SoCs, the individual CPU cores and the SCU/L2 are in separate >> (nested) power areas. Perhaps these power areas are turned off when >> disabling the CPU cores, but not when suspending them. > > BTW, I don't care much about the extra state. > Then stop caring about extra power usage too ;). Seriously this is not a valid argument. >>>> E.g. on non-PSCI platforms with an Ethernet driver that supports >>>> Wake-on-LAN, I can do: >>>> >>>> ethtool -s eth0 wol g >>>> echo mem > /sys/power/state >>>> >>>> and be sure that the system can be woken up by sending a WoL MagicPacket. >>> >>> Still possible with s2idle if CPU_SUSPEND is correctly implemented by >>> the platform. >> >> Sure. But not automatic, as it needs fiddling with mem_sleep. > > I do care about this, as it affects user experience. > Again when you have both "deep" and "standby" suspend states as per your patch set, user has to choose one. No escape from that. -- Regards, Sudeep From mboxrd@z Thu Jan 1 00:00:00 1970 From: sudeep.holla@arm.com (Sudeep Holla) Date: Thu, 23 Feb 2017 15:58:31 +0000 Subject: [PATCH/RFC 0/6] PSCI: Fix non-PMIC wake-up if SYSTEM_SUSPEND cuts power In-Reply-To: References: <1487622809-25127-1-git-send-email-geert+renesas@glider.be> <94167d3a-e005-3af0-d290-a1086684d570@arm.com> <3c8b3f2d-8604-f999-4208-a82f171b64f2@arm.com> <1975396.x0czmkNPOW@aspire.rjw.lan> <35840771-e16f-d6fe-3a89-1b3f51f4a8f3@arm.com> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Geert, On 23/02/17 15:34, Geert Uytterhoeven wrote: > Hi Sudeep, > > On Thu, Feb 23, 2017 at 4:26 PM, Geert Uytterhoeven > wrote: >> On Wed, Feb 22, 2017 at 3:32 PM, Sudeep Holla wrote: >>> On 22/02/17 13:38, Geert Uytterhoeven wrote: >>>> On Wed, Feb 22, 2017 at 12:03 PM, Sudeep Holla wrote: >>>> 4. Patch 3/6 adds a new "shallow" state, as it allows to save more >>>> power (the difference may be due to suboptimal cpuidle platform support on R-Car Gen3, though), >>> >>> Why can't you do that in s2idle mode. Please give me the difference >>> between your shallow state and s2idle state, not just power numbers >>> but the actual state of CPUs and the devices in the system. >> >> From the Linux side, there's not much difference, except that the secondary >> CPU cores are disabled. As that is handled by PSCI, the difference may be >> in the PSCI implementation. I will have to check that... >> >> On these SoCs, the individual CPU cores and the SCU/L2 are in separate >> (nested) power areas. Perhaps these power areas are turned off when >> disabling the CPU cores, but not when suspending them. > > BTW, I don't care much about the extra state. > Then stop caring about extra power usage too ;). Seriously this is not a valid argument. >>>> E.g. on non-PSCI platforms with an Ethernet driver that supports >>>> Wake-on-LAN, I can do: >>>> >>>> ethtool -s eth0 wol g >>>> echo mem > /sys/power/state >>>> >>>> and be sure that the system can be woken up by sending a WoL MagicPacket. >>> >>> Still possible with s2idle if CPU_SUSPEND is correctly implemented by >>> the platform. >> >> Sure. But not automatic, as it needs fiddling with mem_sleep. > > I do care about this, as it affects user experience. > Again when you have both "deep" and "standby" suspend states as per your patch set, user has to choose one. No escape from that. -- Regards, Sudeep