From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932086AbdBURyr (ORCPT ); Tue, 21 Feb 2017 12:54:47 -0500 Received: from foss.arm.com ([217.140.101.70]:35684 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751883AbdBURyi (ORCPT ); Tue, 21 Feb 2017 12:54:38 -0500 Date: Tue, 21 Feb 2017 17:54:29 +0000 From: Mark Rutland To: Pavel Machek Cc: Geert Uytterhoeven , Lorenzo Pieralisi , Sudeep Holla , Lina Iyer , John Stultz , Thomas Gleixner , "Rafael J . Wysocki" , Len Brown , Rob Herring , 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 Subject: Re: [PATCH/RFC 4/6] drivers: firmware: psci: Fix non-PMIC wake-up if SYSTEM_SUSPEND cuts power Message-ID: <20170221175429.GF8605@leverpostej> References: <1487622809-25127-1-git-send-email-geert+renesas@glider.be> <1487622809-25127-5-git-send-email-geert+renesas@glider.be> <20170221110730.GF5021@amd> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170221110730.GF5021@amd> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Feb 21, 2017 at 12:07:30PM +0100, Pavel Machek wrote: > On Mon 2017-02-20 21:33:27, Geert Uytterhoeven wrote: > > 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. > > > > Document and add support for an "arm,psci-system-suspend-is-power-down" > > DT property, so Linux uses a different suspend method when other wake-up > > sources (e.g. wake on LAN, UART or GPIO) are enabled. > > Should we make PSCI return that information? (At least in next > specification version?) Largely, this is somewhat ill-defined, so it's not something that can be easily (or correctly) described by a limited firmware call interface. I believe that the correct way to describe this is to describe the wakeup capabilities on devices. Both ACPI and DT have mechanisms for that today, though it seems that there is confusion as to precisely how to use them. Thanks, Mark. From mboxrd@z Thu Jan 1 00:00:00 1970 From: mark.rutland@arm.com (Mark Rutland) Date: Tue, 21 Feb 2017 17:54:29 +0000 Subject: [PATCH/RFC 4/6] drivers: firmware: psci: Fix non-PMIC wake-up if SYSTEM_SUSPEND cuts power In-Reply-To: <20170221110730.GF5021@amd> References: <1487622809-25127-1-git-send-email-geert+renesas@glider.be> <1487622809-25127-5-git-send-email-geert+renesas@glider.be> <20170221110730.GF5021@amd> Message-ID: <20170221175429.GF8605@leverpostej> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Feb 21, 2017 at 12:07:30PM +0100, Pavel Machek wrote: > On Mon 2017-02-20 21:33:27, Geert Uytterhoeven wrote: > > 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. > > > > Document and add support for an "arm,psci-system-suspend-is-power-down" > > DT property, so Linux uses a different suspend method when other wake-up > > sources (e.g. wake on LAN, UART or GPIO) are enabled. > > Should we make PSCI return that information? (At least in next > specification version?) Largely, this is somewhat ill-defined, so it's not something that can be easily (or correctly) described by a limited firmware call interface. I believe that the correct way to describe this is to describe the wakeup capabilities on devices. Both ACPI and DT have mechanisms for that today, though it seems that there is confusion as to precisely how to use them. Thanks, Mark.