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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 82072C432C0 for ; Wed, 20 Nov 2019 22:36:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4D03C20895 for ; Wed, 20 Nov 2019 22:36:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574289419; bh=MsP73j/TCAPbETzY9SW4Mtnp/AMIF4lbUWWljggg9zc=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=JLZKdCnsXnx5q3hgC/Q86dsGen1Ow3yeW64npkv4XiOOFeUVeuGU39O4xltU4A0Xk v5nIeeBHJPjNCJ+0q1UTk0sGsdErNjjeV66XiyPfOcvyfRlMWEgcNG68BDO8Kn0oHx Wvom+jDJvihNiZ9wL8x1izdZzZ5hoT8Ixhld7zV4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725936AbfKTWg6 (ORCPT ); Wed, 20 Nov 2019 17:36:58 -0500 Received: from mail-ot1-f48.google.com ([209.85.210.48]:44087 "EHLO mail-ot1-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725842AbfKTWg6 (ORCPT ); Wed, 20 Nov 2019 17:36:58 -0500 Received: by mail-ot1-f48.google.com with SMTP id c19so1093912otr.11 for ; Wed, 20 Nov 2019 14:36:58 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=myHFRg//BXqxgupoupGLt3gspBxW093kvd1Tmwb1RVU=; b=nGB+w5AxkO+gMZ8bAUf8qXnRklJl8fCZDPihZK4PMJuUEiMjisDfdDM27Fe1L73ssG eHkUvpjZhFIGig0A6Zjv1hSZnG7c05+7p0JP+u6VU/zWuJUrz3VCQhSfZhu/bAj1o+8f kCGPrAMn+Kkj8dfLqZ5Q0Z/bgrUYrXVIs17PYdtZ5EOnrfHrrZJLENqgoagRfrc9q6bb qFREep/FXBAz7YSuAQ/4sGV9DxaMcZ5AdlphPDKlo8uxg42CbDP/PNxU5KH+LPf4MPQz 2+LQkR8w29l1ibkWjj0r+358xHkxe4NLFMxH1M7XpmJCOdAULQFF2+SxV4HdWLr8vrF2 bk0Q== X-Gm-Message-State: APjAAAVGyAW+dac6xSjzIv7oiWdSHru+bid3VGEoTihmmSV6vXBx1le/ 6KOBEqGIewwGfAJ+Xp6mOmUlD682RPHH+2hrl7Q= X-Google-Smtp-Source: APXvYqwxlg6kSCDhKNuJDdrURCGSot1SEgUubMtFnoUzkO4krIMh83hfp73CeIHdHwHoLqzzkg0XvbmlFcOLVwpSx7o= X-Received: by 2002:a9d:4c85:: with SMTP id m5mr3826223otf.118.1574289418016; Wed, 20 Nov 2019 14:36:58 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: "Rafael J. Wysocki" Date: Wed, 20 Nov 2019 23:36:46 +0100 Message-ID: Subject: Re: PEP driver for Linux To: Alex Deucher Cc: "Rafael J. Wysocki" , Linux PM Content-Type: text/plain; charset="UTF-8" Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On Wed, Nov 20, 2019 at 11:30 PM Alex Deucher wrote: > > Hi, > > I'm trying to understand how to hook in a platform specific driver to > support S0ix on Linux. Windows defines a platform PEP (power engine > plugin) driver which the platform uses to coordinate the the low power > state of the SoC. I'm not entirely sure how this would work on Linux. > My understanding is that the all devices go through their suspend > routines and then this PEP driver is responsible for putting the SOC > into it's lowest power state. On a lot of platforms the PEP driver > interacts with a platform specific ACPI method to tell the platform > which devices are suspended. I'm not really sure how this should be > handled on Linux. It is done already, through the PEP device _DSM (see suspend-to-idle support in drivers/acpi/sleep.c). Thanks!