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=-2.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 417F3C432BE for ; Sat, 24 Jul 2021 20:25:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 22E2460E09 for ; Sat, 24 Jul 2021 20:25:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229642AbhGXTpO (ORCPT ); Sat, 24 Jul 2021 15:45:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37244 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229508AbhGXTpM (ORCPT ); Sat, 24 Jul 2021 15:45:12 -0400 Received: from mail-pj1-x102d.google.com (mail-pj1-x102d.google.com [IPv6:2607:f8b0:4864:20::102d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 483D5C061575; Sat, 24 Jul 2021 13:25:44 -0700 (PDT) Received: by mail-pj1-x102d.google.com with SMTP id g23-20020a17090a5797b02901765d605e14so8601608pji.5; Sat, 24 Jul 2021 13:25:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=oX5fp2Nd3pjI/G9YdONxiLdBOXyu28WtsV/xr2FFBcM=; b=MleA1nfsh6fJ0gs2dghL4xrngg8YiagMbY7B66ZlCMD2z5AztzMGSQPwrXyhZd8MkQ L8oT1tz+xo/ioxQk/QOP6XONFYOZr7bosbTJXlqX2uDnQh4yLsqWnifbQ+BHLoaV9tKp EFLASh3QItzEHlx+pq40+jRlGFM9dSKxNmcCVadldLbikD69tYE6f0xgwUMBWG4bCrl/ TTwXZOAz2c7G2aLRhX6hDMeuj9A87fLkG26utfBsREOVhnXkdWtTqrA7ga24EuM3R0jJ q+4HpZIyf8Ihat9zxU0sJrAAd+OJUGnthorkRyUF+Yk1B9IqQ7iZrHylwmU1XgxyeRUP SntA== 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:content-transfer-encoding; bh=oX5fp2Nd3pjI/G9YdONxiLdBOXyu28WtsV/xr2FFBcM=; b=PcS06fYUA9R1NQfxFHJFidPPYhKqNi/vdaUIEArMDxUwRv4pIR2SigbAskAS92bRQ6 m8KJI2ABAim8unIsF05B6xX5NKZKn3Zlr2EX9ci8j2nZGtaBphE0fBeFWDdDU6rqgsRw OaMwutVn/27pQEpbH+X0WMTqkQBlOZZjc4DSyjmmVwbAqePu9dzCo6FjnI5MYI++hjqP EvrqfEqSKogm4e0/ZIQovCu9Yj/J9fjqC+TAKsKQVYdS5eiBB6vdcu2rSAfbcj/y5pvB kMsLd4BM57Y5J18rOcAgtYRHzeswobJD1SSHkm8YH+ifcOo1tRjZ+POJ+Por0+0rll9v i3lA== X-Gm-Message-State: AOAM533TnOcBer4TWC87C/usFagTX+mNX0Dw8uYl/+1S/D0knRN6jG6I rH1K9/10laPoPXIRpwU8SjlHL7O2usSEy7+KyCY= X-Google-Smtp-Source: ABdhPJwUTRel3gjPkDQOX+a2yHZ/w3me8pjMINp3dKxourGyiImC63ckIod43RoF5q1yN0p8t9bUdUAmzFZPdlxmw7M= X-Received: by 2002:a17:90b:1194:: with SMTP id gk20mr19462244pjb.181.1627158343731; Sat, 24 Jul 2021 13:25:43 -0700 (PDT) MIME-Version: 1.0 References: <20210723202157.2425-1-michael.a.bottini@linux.intel.com> <20210723202157.2425-2-michael.a.bottini@linux.intel.com> <27751c8ff02d98cabd512472b29078b11f4bdf0e.camel@linux.intel.com> In-Reply-To: <27751c8ff02d98cabd512472b29078b11f4bdf0e.camel@linux.intel.com> From: Andy Shevchenko Date: Sat, 24 Jul 2021 23:25:06 +0300 Message-ID: Subject: Re: [PATCH 2/2] platform/x86/intel/pmc: Add PSON residency counter To: David Box Cc: Michael Bottini , "rjw@rjwysocki.net" , "lenb@kernel.org" , "irenic.rajneesh@gmail.com" , "hdegoede@redhat.com" , "mgross@linux.intel.com" , "linux-acpi@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "platform-driver-x86@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jul 24, 2021 at 10:49 PM David E. Box wrote: > On Sat, 2021-07-24 at 11:29 +0300, Andy Shevchenko wrote: > > On Friday, July 23, 2021, Michael Bottini > > wrote: > > > Tiger Lake devices have the capability to track the duration > > > of time that their Power Supply Units (PSUs) are turned off during > > > S0ix. > > > This patch adds a debugfs file `pson_residency_usec` to provide > > > access to this counter. > > > > > > In order to determine whether the device is capable of PSON, > > > use acpi_init_properties() to reevaluate _DSD. > > > > > > > > > > It=E2=80=99s direct abuse of ACPI specification as I read it: > > > > =E2=80=9C_DSD must return the same data each time it is evaluated. Firm= ware > > should not expect it to be evaluated every time (in case it is > > implemented as a method).=E2=80=9D > > > > > > NAK to the series. > > Okay, we'll check with the BIOS folks. They are setting this property > from _STA. They may not expect OSPM to reevaluate _DSD. Does it matter? > But they may > have expected that OSPM doesn't attempt to read _DSD until after _STA > is executed. They may study a bit of ACPI specification perhaps? Or if there is indeed an issue with the specification language (so native-speaking people misinterpret above) then ECR to ASWG should be submitted? --=20 With Best Regards, Andy Shevchenko