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 AD48DC6FA81 for ; Fri, 2 Sep 2022 17:25:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235392AbiIBRZ5 (ORCPT ); Fri, 2 Sep 2022 13:25:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44630 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234495AbiIBRZ5 (ORCPT ); Fri, 2 Sep 2022 13:25:57 -0400 Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3C20A4BA45; Fri, 2 Sep 2022 10:25:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1662139556; x=1693675556; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=8PnpdD07t1F9xEIN5xQAbzg3qh6AvWLc6Y0NYuKP/4I=; b=YW6EAlqT99cHaTRJz2E5DgULzA4/VZ5NV7MjnE/KlMXHoqhmCFIJhu8R sidr4Q1kA231vhvmYwotjItQfeVrx9KZ4mx4EPEAruDgARES5125PtZXH gQMTRLirlda4500m+aM7eZlciwld6aAZjNVBLlJ41/G3T06oHqRD7T2dO iFE9QR+z4J5Ob/98n7lEjm7NQrwC7rE23CCGdK+f1GSRsDh9DYlAAtAHm N8av1xOz/58fWB/kdvvCF/kkCtABGNFDSBJwYeNaTNKFk0y95wCTQJUqW BKfZHGTqVeOVgjDgF5NR29YiHfXy6+Cm9d2Wr/2F3M0CcVJog4L3ryASV g==; X-IronPort-AV: E=McAfee;i="6500,9779,10458"; a="296037303" X-IronPort-AV: E=Sophos;i="5.93,283,1654585200"; d="scan'208";a="296037303" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Sep 2022 10:25:55 -0700 X-IronPort-AV: E=Sophos;i="5.93,283,1654585200"; d="scan'208";a="674436293" Received: from cthornbr-mobl.amr.corp.intel.com (HELO [10.251.3.254]) ([10.251.3.254]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Sep 2022 10:25:54 -0700 Message-ID: Date: Fri, 2 Sep 2022 10:25:54 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Firefox/91.0 Thunderbird/91.11.0 Subject: Re: [PATCH 2/4] PCI/PTM: Enable PTM when restoring state Content-Language: en-US To: Bjorn Helgaas , Kai-Heng Feng , Rajvi Jingar , "Rafael J . Wysocki" Cc: Koba Ko , Mika Westerberg , "David E . Box" , linux-pci@vger.kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Bjorn Helgaas References: <20220902145835.344302-1-helgaas@kernel.org> <20220902145835.344302-3-helgaas@kernel.org> From: Sathyanarayanan Kuppuswamy In-Reply-To: <20220902145835.344302-3-helgaas@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org On 9/2/22 7:58 AM, Bjorn Helgaas wrote: > From: Bjorn Helgaas > > The suspend path may disable PTM before saving config state, which means > the PCI_PTM_CTRL_ENABLE bit in the saved state may be cleared even though > we want PTM to be enabled when resuming. If suspend is disabling PTM separately, why not enable it during the resume operation? Why club it with PTM state restoration? > > If "dev->ptm_enabled" is set, it means PTM should be enabled, so make sure > PCI_PTM_CTRL_ENABLE is set when restoring the PTM state. > > Signed-off-by: Bjorn Helgaas > --- > drivers/pci/pcie/ptm.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/pci/pcie/ptm.c b/drivers/pci/pcie/ptm.c > index b6a417247ce3..3115601a85ef 100644 > --- a/drivers/pci/pcie/ptm.c > +++ b/drivers/pci/pcie/ptm.c > @@ -82,6 +82,14 @@ void pci_restore_ptm_state(struct pci_dev *dev) > return; > > cap = (u16 *)&save_state->cap.data[0]; > + > + /* > + * The suspend path may disable PTM before saving config state. > + * Make sure PCI_PTM_CTRL_ENABLE is set if PTM should be enabled. > + */ > + if (dev->ptm_enabled) > + *cap |= PCI_PTM_CTRL_ENABLE; > + > pci_write_config_word(dev, ptm + PCI_PTM_CTRL, *cap); > } > -- Sathyanarayanan Kuppuswamy Linux Kernel Developer