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 X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 88B11C2D0A3 for ; Thu, 12 Nov 2020 14:57:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1CE3822255 for ; Thu, 12 Nov 2020 14:57:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728515AbgKLO5y (ORCPT ); Thu, 12 Nov 2020 09:57:54 -0500 Received: from foss.arm.com ([217.140.110.172]:52402 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727035AbgKLO5y (ORCPT ); Thu, 12 Nov 2020 09:57:54 -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 A9469139F; Thu, 12 Nov 2020 06:57:53 -0800 (PST) Received: from bogus (unknown [10.57.15.107]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id E41353F73C; Thu, 12 Nov 2020 06:57:51 -0800 (PST) Date: Thu, 12 Nov 2020 14:57:44 +0000 From: Sudeep Holla To: Cristian Marussi Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, lukasz.luba@arm.com, james.quinlan@broadcom.com, Sudeep Holla , Jonathan.Cameron@Huawei.com Subject: Re: [PATCH v2 1/1] firmware: arm_scmi: Add SCMI System Power Control driver Message-ID: <20201112145744.wwehqweh2aqo7klp@bogus> References: <20201026205531.25585-1-cristian.marussi@arm.com> <20201026205531.25585-2-cristian.marussi@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201026205531.25585-2-cristian.marussi@arm.com> User-Agent: NeoMutt/20171215 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 26, 2020 at 08:55:31PM +0000, Cristian Marussi wrote: > Add an SCMI System Power control driver to handle platform's requests > carried by SYSTEM_POWER_STATE_NOTIFIER notifications: such platform > requested system power state transitions are handled accordingly, > gracefully or forcefully, depending on the notifications' message flags. > > Graceful requests are by default relayed to userspace using the same > Kernel API used to handle ACPI Shutdown bus events: alternatively, instead, > a few available module parameters can be used to tunnel instead such > requests to userspace via signals addressed to CAD pid. > > When handling graceful requests, grant userspace processes a maximum > (configurable) time to perform their duties and then revert to a forceful > transition, so avoiding completely timing out platform's maximum grace time > and hitting possible abrupt power-cuts. > > Signed-off-by: Cristian Marussi > --- > drivers/firmware/Kconfig | 12 + > drivers/firmware/arm_scmi/Makefile | 1 + > .../firmware/arm_scmi/scmi_power_control.c | 387 ++++++++++++++++++ > 3 files changed, 400 insertions(+) > create mode 100644 drivers/firmware/arm_scmi/scmi_power_control.c > [nit] Since you have just one patch, it is generally preferred to place all the extra non commit messages here after diff stat to have a single thread of discussion. Anyways, probably ccing Arnd/Greg/or anyone who has made some feature changes in this area(e.g. kernel/reboot.c) might help to get some useful feedback here. -- Regards, Sudeep