From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 02A5CC433F5 for ; Thu, 3 Feb 2022 11:15:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350145AbiBCLPY (ORCPT ); Thu, 3 Feb 2022 06:15:24 -0500 Received: from foss.arm.com ([217.140.110.172]:39688 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232228AbiBCLPX (ORCPT ); Thu, 3 Feb 2022 06:15:23 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 140F011D4; Thu, 3 Feb 2022 03:15:23 -0800 (PST) Received: from bogus (unknown [10.57.41.150]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7DCE63F774; Thu, 3 Feb 2022 03:15:21 -0800 (PST) Date: Thu, 3 Feb 2022 11:14:35 +0000 From: Sudeep Holla To: Florian Fainelli Cc: linux-arm-kernel@lists.infradead.org, "maintainer:BROADCOM BCM7XXX ARM ARCHITECTURE" , Mark Rutland , Sudeep Holla , Lorenzo Pieralisi , open list Subject: Re: [PATCH 0/4] Broadcom STB PM PSCI extensions Message-ID: <20220203111435.e3eblv47ljkwkvwf@bogus> References: <20220122035421.4086618-1-f.fainelli@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220122035421.4086618-1-f.fainelli@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 21, 2022 at 07:54:17PM -0800, Florian Fainelli wrote: > Hi all, > > This patch series contains the Broadcom STB PSCI extensions which adds > some additional functions on top of the existing standard PSCI interface > which is the reason for having the driver implement a custom > suspend_ops. > > These platforms have traditionally supported a mode that is akin to > ACPI's S2 with the CPU in WFI and all of the chip being clock gated > which is entered with "echo standby > /sys/power/state". Additional a > true suspend to DRAM as defined in ACPI by S3 is implemented with "echo > mem > /sys/power/state". How different is the above "standby" state compare to the standard "idle" (a.k.a suspend-to-idle which is different from system-to-ram/S3) ? Suspend to idle takes all the CPUs to lowest possible power state instead of cpu-hotplug in S2R. Also I assume some userspace has to identify when to enter "standby" vs "mem" right ? I am trying to see how addition of "idle" changes that(if it does). Sorry for too many questions. -- Regards, Sudeep From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 94442C433EF for ; Thu, 3 Feb 2022 11:16:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=L4mBGToXeJjTQvWQGPccLVqmYpS/0iMt8ULokU+BXdo=; b=bkL3lrmAupP2OV 9UIYv1201/pXDOV83v63Ds/NNR/534ksoS+lLbHRMQgDM0TBxljl4IDgAonWvaHKozBZ/yvR7jjjx QTAb4pU9FWHQbEodlXbi25H7Zh8deFNJm9qXzyxDU7UsdU9o0IO3VZQj38eaYtvqxfzqzZt849Wz1 72e2ShRT0c2TN0GWGaszhoSCyPhdPK/pa+8kV8bbjp2+69qcXp6a3mwJ1UX4b5lTc3Tn1X4jAM/E8 c89txCclCG8ZCtknMASKBV5E3oVw1MtOOQ376Ki3DBdxsNfMoIHP8OC+BRw5xd8MpH0tTl8Jws0/b nT/0C2Q8KoBtQiGM4BzA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nFa5L-000w5A-SK; Thu, 03 Feb 2022 11:15:31 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nFa5H-000w42-51 for linux-arm-kernel@lists.infradead.org; Thu, 03 Feb 2022 11:15:28 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 140F011D4; Thu, 3 Feb 2022 03:15:23 -0800 (PST) Received: from bogus (unknown [10.57.41.150]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 7DCE63F774; Thu, 3 Feb 2022 03:15:21 -0800 (PST) Date: Thu, 3 Feb 2022 11:14:35 +0000 From: Sudeep Holla To: Florian Fainelli Cc: linux-arm-kernel@lists.infradead.org, "maintainer:BROADCOM BCM7XXX ARM ARCHITECTURE" , Mark Rutland , Sudeep Holla , Lorenzo Pieralisi , open list Subject: Re: [PATCH 0/4] Broadcom STB PM PSCI extensions Message-ID: <20220203111435.e3eblv47ljkwkvwf@bogus> References: <20220122035421.4086618-1-f.fainelli@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20220122035421.4086618-1-f.fainelli@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220203_031527_266072_924EF810 X-CRM114-Status: GOOD ( 13.76 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Jan 21, 2022 at 07:54:17PM -0800, Florian Fainelli wrote: > Hi all, > > This patch series contains the Broadcom STB PSCI extensions which adds > some additional functions on top of the existing standard PSCI interface > which is the reason for having the driver implement a custom > suspend_ops. > > These platforms have traditionally supported a mode that is akin to > ACPI's S2 with the CPU in WFI and all of the chip being clock gated > which is entered with "echo standby > /sys/power/state". Additional a > true suspend to DRAM as defined in ACPI by S3 is implemented with "echo > mem > /sys/power/state". How different is the above "standby" state compare to the standard "idle" (a.k.a suspend-to-idle which is different from system-to-ram/S3) ? Suspend to idle takes all the CPUs to lowest possible power state instead of cpu-hotplug in S2R. Also I assume some userspace has to identify when to enter "standby" vs "mem" right ? I am trying to see how addition of "idle" changes that(if it does). Sorry for too many questions. -- Regards, Sudeep _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel