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 AA446E9271B for ; Thu, 5 Oct 2023 17:26:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229937AbjJER0g (ORCPT ); Thu, 5 Oct 2023 13:26:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35248 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231417AbjJERZ6 (ORCPT ); Thu, 5 Oct 2023 13:25:58 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 42E03210D for ; Thu, 5 Oct 2023 10:22:29 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 623D6C433CD; Thu, 5 Oct 2023 17:22:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1696526548; bh=mqBeiX5OVUWwXM68XaY4QT/4g94lUfVx5Y0ylvmxGdc=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=b8k/rCsdz8pan5dRzi8+/lsUavpUwau3IowbSWxRcJacux6rT2FM9myFuRJkLfMPy YAblnbLnKkRLu5zeThqy0rguCwQinKnQ9grOFusje/CT7qof1Tg3q5BWgVAI8puOyP D2RrlClv4ySdPz6nQPITmneWfNF7fPEToTOWyvuO0kdf1nPs0AACg0ItjywMbUhjDF gbS7GfEC0UTIAq8cqAhtcuy0ZjNeiZqhxo/jo3S8/6oEfV7hJRQS//nxd83SWJS/gx Yi42VZRIlleZdbzQpSAeqKv6V0q68iw5Wb/9rtneLrR6apPj9OubqJCOX0tE8nM4NP h9fWPCwO1ZpCA== Date: Thu, 5 Oct 2023 12:22:26 -0500 From: Bjorn Helgaas To: Thomas Witt Cc: Mika Westerberg , Bjorn Helgaas , Kuppuswamy Sathyanarayanan , Vidya Sagar , "Rafael J. Wysocki" , Kai-Heng Feng , "David E . Box" , Tasev Nikola , Mark Enriquez , Koba Ko , Werner Sembach , Ilpo =?utf-8?B?SsOkcnZpbmVu?= , =?utf-8?B?5ZCz5piK5r6E?= Ricky , linux-pci@vger.kernel.org Subject: Re: [PATCH v4] PCI/ASPM: Add back L1 PM Substate save and restore Message-ID: <20231005172226.GA781644@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <923d8df0-1112-aca9-8289-c6e2457298cd@witt.link> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Thu, Oct 05, 2023 at 05:57:52PM +0200, Thomas Witt wrote: > On 05/10/2023 17:30, Bjorn Helgaas wrote: > ... > > Right, without the denylist, I expect Thomas' TUXEDO to fail, but I > > still hope we can figure out why. If we just keep it on the denylist, > > that system will suffer from more power consumption than necessary, > > but only after suspend/resume. > > > > A denylist seems like the absolute last resort. In this case we don't > > know about anything *wrong* with those platforms; all we know is that > > our resume path doesn't work. It's likely that it fails on other > > platforms we haven't heard about, too. > > The best guess from Mika and David was a firmware issue, but I run the same > Firmware revision as Werner. I even reflashed the Firmware, but that did not > change anything: Possibly a BIOS settings difference? > Quoting David Box: > > I agree that we should pursue an exception for your system. This is > > looking like a firmware bug. One thing we did notice in the turbostat > > results is your IRTL (Interrupt Response Time Limit) values are bogus: > > > > cpu6: MSR_PKGC3_IRTL: 0x0000884e (valid, 79872 ns) > > cpu6: MSR_PKGC6_IRTL: 0x00008000 (valid, 0 ns) > > cpu6: MSR_PKGC7_IRTL: 0x00008000 (valid, 0 ns) > > cpu6: MSR_PKGC8_IRTL: 0x00008000 (valid, 0 ns) > > cpu6: MSR_PKGC9_IRTL: 0x00008000 (valid, 0 ns) > > cpu6: MSR_PKGC10_IRTL: 0x00008000 (valid, 0 ns) > > > > This is despite the PKGC configuration register showing that all > > states are enabled: > > > > cpu6: MSR_PKG_CST_CONFIG_CONTROL: 0x1e008008 (UNdemote-C3, UNdemote-C1, > demote- > C3, demote-C1, locked, pkg-cstate-limit=8 (unlimited)) > > > > Firmware sets this. I can't find this discussion, but if there's a firmware issue related to IRTL MSRs, I would want the workaround in intel-idle.c or whatever code deals with the MSRs, not in the ASPM code. Bjorn