From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752004AbdBUKjK (ORCPT ); Tue, 21 Feb 2017 05:39:10 -0500 Received: from foss.arm.com ([217.140.101.70]:58128 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751919AbdBUKjF (ORCPT ); Tue, 21 Feb 2017 05:39:05 -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> Cc: Lorenzo Pieralisi , Mark Rutland , Lina Iyer , John Stultz , Thomas Gleixner , "Rafael J . Wysocki" , Len Brown , Pavel Machek , Rob Herring , Sudeep Holla , Magnus Damm , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-renesas-soc@vger.kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org From: Sudeep Holla Organization: ARM Message-ID: <69ab75a1-2e04-19e2-d1ad-12ca1cfc7625@arm.com> Date: Tue, 21 Feb 2017 10:38:54 +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: <1487622809-25127-1-git-send-email-geert+renesas@glider.be> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Geert, On 20/02/17 20:33, Geert Uytterhoeven wrote: > Hi all, > > This patch series adds support for using non-PMIC wake-up sources on the > Renesas R-Car Gen3 (H3 or M3-W) Salvator-X development boards. > > Nothing in the PSCI specification requires the SoC to remain powered and > to support wake-up sources when suspended using SYSTEM_SUSPEND. > If the firmware implements the PSCI SYSTEM_SUSPEND operation by cutting > power to the SoC, the only possibly wake-up sources are thus the ones > connected to the PMIC. > OK, but I don't see any issue with that. That's exactly how it works on ARM Juno platform. The SoC is powered down. > To allow other wake-up sources, this patch series documents and adds > support for an "arm,psci-system-suspend-is-power-down" DT property, so NACK, you don't need any such properties. > Linux uses a different suspend method when other wake-up sources (e.g. > wake on LAN, UART or GPIO) are enabled. Hence the user no longer has to > manually restrict "mem" suspend to "s2idle" or "shallow" states using: > Have you explored suspend-to-idle instead ? It looks like thats exactly what you are doing in this patch set. You also get low latency for free as it just enters the deepest idle state on all CPUs instead of hotplugging out all the secondaries. -- Regards, Sudeep From mboxrd@z Thu Jan 1 00:00:00 1970 From: sudeep.holla@arm.com (Sudeep Holla) Date: Tue, 21 Feb 2017 10:38:54 +0000 Subject: [PATCH/RFC 0/6] PSCI: Fix non-PMIC wake-up if SYSTEM_SUSPEND cuts power In-Reply-To: <1487622809-25127-1-git-send-email-geert+renesas@glider.be> References: <1487622809-25127-1-git-send-email-geert+renesas@glider.be> Message-ID: <69ab75a1-2e04-19e2-d1ad-12ca1cfc7625@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Geert, On 20/02/17 20:33, Geert Uytterhoeven wrote: > Hi all, > > This patch series adds support for using non-PMIC wake-up sources on the > Renesas R-Car Gen3 (H3 or M3-W) Salvator-X development boards. > > Nothing in the PSCI specification requires the SoC to remain powered and > to support wake-up sources when suspended using SYSTEM_SUSPEND. > If the firmware implements the PSCI SYSTEM_SUSPEND operation by cutting > power to the SoC, the only possibly wake-up sources are thus the ones > connected to the PMIC. > OK, but I don't see any issue with that. That's exactly how it works on ARM Juno platform. The SoC is powered down. > To allow other wake-up sources, this patch series documents and adds > support for an "arm,psci-system-suspend-is-power-down" DT property, so NACK, you don't need any such properties. > Linux uses a different suspend method when other wake-up sources (e.g. > wake on LAN, UART or GPIO) are enabled. Hence the user no longer has to > manually restrict "mem" suspend to "s2idle" or "shallow" states using: > Have you explored suspend-to-idle instead ? It looks like thats exactly what you are doing in this patch set. You also get low latency for free as it just enters the deepest idle state on all CPUs instead of hotplugging out all the secondaries. -- Regards, Sudeep