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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_MUTT autolearn=unavailable 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 5D96BC04AAC for ; Mon, 20 May 2019 17:57:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3982B216C4 for ; Mon, 20 May 2019 17:57:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558375057; bh=ffyeII7/nmRLuGHHd0K9nhnUiqgQDgqqy1z0eKBOvyI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=JJJVF3DZu1xhVFVGAwXF3TpvBKDTrH4WclwqAWa5L+Nc+N5wxueEAAtguO8fHxw3U E/U/JjW27XYpAo592/tGkhwuzOvYILft2xRtDgT132QqG5NwMYLgbmrRYSF18Hkrxz JmK2i1Vyc9dMfZx/g+kqYYo/Ub8ozmWqaXoJfq98= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727058AbfETR5c (ORCPT ); Mon, 20 May 2019 13:57:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:52646 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726566AbfETR5c (ORCPT ); Mon, 20 May 2019 13:57:32 -0400 Received: from localhost (173-25-83-245.client.mchsi.com [173.25.83.245]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BD278206B6; Mon, 20 May 2019 17:57:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558375051; bh=ffyeII7/nmRLuGHHd0K9nhnUiqgQDgqqy1z0eKBOvyI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=e5o0BcOkg4n6pUD8iLQCFZBCxXxk4bt+VcQsAxSnABUsDz8bRFJlp3uKi8ivj++cG USpRioxQgHMiEFvvhoCwIZ8Dg7CKelyHjYARsgbKxU4iMl/ejfFsj8YIAwiA7N8MLU eBEAsroj+DCYjUrChLCxOo3iWOMJVat5EBKL8j6g= Date: Mon, 20 May 2019 12:57:29 -0500 From: Bjorn Helgaas To: Vidya Sagar Cc: Christoph Hellwig , lorenzo.pieralisi@arm.com, robh+dt@kernel.org, mark.rutland@arm.com, thierry.reding@gmail.com, jonathanh@nvidia.com, kishon@ti.com, catalin.marinas@arm.com, will.deacon@arm.com, jingoohan1@gmail.com, gustavo.pimentel@synopsys.com, mperttunen@nvidia.com, linux-pci@vger.kernel.org, devicetree@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kthota@nvidia.com, mmaddireddy@nvidia.com, sagar.tv@gmail.com Subject: Re: [PATCH V6 02/15] PCI/PME: Export pcie_pme_disable_msi() & pcie_pme_no_msi() APIs Message-ID: <20190520175729.GC49425@google.com> References: <20190513050626.14991-1-vidyas@nvidia.com> <20190513050626.14991-3-vidyas@nvidia.com> <20190513072539.GA27708@infradead.org> <3a8cea93-2aeb-e5e2-4d56-f0c6449073c3@nvidia.com> <20190516133426.GC101793@google.com> <20190517132453.GA30700@google.com> <20190517185545.GB49425@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Sat, May 18, 2019 at 07:28:29AM +0530, Vidya Sagar wrote: > On 5/18/2019 12:25 AM, Bjorn Helgaas wrote: > > On Fri, May 17, 2019 at 11:23:36PM +0530, Vidya Sagar wrote: > > > On 5/17/2019 6:54 PM, Bjorn Helgaas wrote: > > > > Do you have "lspci -vvxxx" output for the root ports handy? > > > > > > > > If there's some clue in the standard config space that would tell us > > > > that MSI works for some events but not others, we could make the PCI > > > > core pay attention it. That would be the best solution because it > > > > wouldn't require Tegra-specific code. > > > > > > Here is the output of 'lspci vvxxx' for one of Tegra194's root ports. > > > > Thanks! > > > > This port advertises both MSI and MSI-X, and neither one is enabled. > > This particular port doesn't have a slot, so hotplug isn't applicable > > to it. > > > > But if I understand correctly, if MSI or MSI-X were enabled and the > > port had a slot, the port would generate MSI/MSI-X hotplug interrupts. > > But PME and AER events would still cause INTx interrupts (even with > > MSI or MSI-X enabled). > > > > Do I have that right? I just want to make sure that the reason for > > PME being INTx is a permanent hardware choice and that it's not > > related to MSI and MSI-X currently being disabled. > > Yes. Thats right. Its hardware choice that our hardware engineers made to > use INTx for PME instead of MSI irrespective of MSI/MSI-X enabled/disabled > in the root port. Here are more spec references that seem applicable: - PCIe r4.0, sec 7.7.1.2 (Message Control Register for MSI) says: MSI Enable – If Set and the MSI-X Enable bit in the MSI-X Message Control register (see Section 7.9.2) is Clear, the Function is permitted to use MSI to request service and is prohibited from using INTx interrupts. - PCIe r4.0, sec 7.7.2.2 (Message Control Register for MSI-X) says: MSI-X Enable – If Set and the MSI Enable bit in the MSI Message Control register (see Section 6.8.1.3) is Clear, the Function is permitted to use MSI-X to request service and is prohibited from using INTx interrupts (if implemented). I read that to mean a device is prohibited from using MSI/MSI-X for some interrupts and INTx for others. Since Tegra194 cannot use MSI/MSI-X for PME, it should use INTx for *all* interrupts. That makes the MSI/MSI-X Capabilities superfluous, and they should be omitted. If we set pdev->no_msi for Tegra194, we'll avoid MSI/MSI-X completely, so we'll assume *all* interrupts including hotplug will be INTx. Will that work? 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=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT 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 BF537C04AAF for ; Mon, 20 May 2019 17:57:54 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9B9FC206B6 for ; Mon, 20 May 2019 17:57:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="ltvpaHc/"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="e5o0BcOk" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9B9FC206B6 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=amI9hGTgDzR1nKixSKiMhWcC3g9lJDHh2Us4HDY9bMg=; b=ltvpaHc/Mb7m// Ld+tFcCLCQSeMrggvewAkhcbQLP+tVRsMQBjmAfBp0FJN5C1wLIVBUWKcaA1rpJW1AlAkR2G0GA8k Nxnay1bV0lojtnEdDRip2mrC+6OBYZT9xa6rPelDAhtfCMif3krvqXFYfzL/oQn4fY/KHNgfKwVvP WiaBSG2UYreTUGybQlPKq26DNoLS1v8MhpXEw9ivgSavkBTeC9xL+h6ZSIHEquV6V31Ho9BGz0DzK pYUqVlsPJSZ9I7Xx0IXQz6xoX1wgAA6Rh7xeyjmCcbvtnHCZinlBpBmMpJF3GSdlixwqpD79lsGVP SiJWMdZS8EQrqE15HGfg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hSmXi-0001M4-BQ; Mon, 20 May 2019 17:57:46 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hSmXT-00014f-SV for linux-arm-kernel@lists.infradead.org; Mon, 20 May 2019 17:57:44 +0000 Received: from localhost (173-25-83-245.client.mchsi.com [173.25.83.245]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BD278206B6; Mon, 20 May 2019 17:57:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1558375051; bh=ffyeII7/nmRLuGHHd0K9nhnUiqgQDgqqy1z0eKBOvyI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=e5o0BcOkg4n6pUD8iLQCFZBCxXxk4bt+VcQsAxSnABUsDz8bRFJlp3uKi8ivj++cG USpRioxQgHMiEFvvhoCwIZ8Dg7CKelyHjYARsgbKxU4iMl/ejfFsj8YIAwiA7N8MLU eBEAsroj+DCYjUrChLCxOo3iWOMJVat5EBKL8j6g= Date: Mon, 20 May 2019 12:57:29 -0500 From: Bjorn Helgaas To: Vidya Sagar Subject: Re: [PATCH V6 02/15] PCI/PME: Export pcie_pme_disable_msi() & pcie_pme_no_msi() APIs Message-ID: <20190520175729.GC49425@google.com> References: <20190513050626.14991-1-vidyas@nvidia.com> <20190513050626.14991-3-vidyas@nvidia.com> <20190513072539.GA27708@infradead.org> <3a8cea93-2aeb-e5e2-4d56-f0c6449073c3@nvidia.com> <20190516133426.GC101793@google.com> <20190517132453.GA30700@google.com> <20190517185545.GB49425@google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190520_105732_272548_C9C46FFB X-CRM114-Status: GOOD ( 20.75 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: mark.rutland@arm.com, devicetree@vger.kernel.org, lorenzo.pieralisi@arm.com, mperttunen@nvidia.com, mmaddireddy@nvidia.com, linux-pci@vger.kernel.org, catalin.marinas@arm.com, will.deacon@arm.com, linux-kernel@vger.kernel.org, robh+dt@kernel.org, jonathanh@nvidia.com, Christoph Hellwig , kthota@nvidia.com, thierry.reding@gmail.com, gustavo.pimentel@synopsys.com, jingoohan1@gmail.com, linux-tegra@vger.kernel.org, kishon@ti.com, linux-arm-kernel@lists.infradead.org, sagar.tv@gmail.com Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org T24gU2F0LCBNYXkgMTgsIDIwMTkgYXQgMDc6Mjg6MjlBTSArMDUzMCwgVmlkeWEgU2FnYXIgd3Jv dGU6Cj4gT24gNS8xOC8yMDE5IDEyOjI1IEFNLCBCam9ybiBIZWxnYWFzIHdyb3RlOgo+ID4gT24g RnJpLCBNYXkgMTcsIDIwMTkgYXQgMTE6MjM6MzZQTSArMDUzMCwgVmlkeWEgU2FnYXIgd3JvdGU6 Cj4gPiA+IE9uIDUvMTcvMjAxOSA2OjU0IFBNLCBCam9ybiBIZWxnYWFzIHdyb3RlOgo+ID4gPiA+ IERvIHlvdSBoYXZlICJsc3BjaSAtdnZ4eHgiIG91dHB1dCBmb3IgdGhlIHJvb3QgcG9ydHMgaGFu ZHk/Cj4gPiA+ID4gCj4gPiA+ID4gSWYgdGhlcmUncyBzb21lIGNsdWUgaW4gdGhlIHN0YW5kYXJk IGNvbmZpZyBzcGFjZSB0aGF0IHdvdWxkIHRlbGwgdXMKPiA+ID4gPiB0aGF0IE1TSSB3b3JrcyBm b3Igc29tZSBldmVudHMgYnV0IG5vdCBvdGhlcnMsIHdlIGNvdWxkIG1ha2UgdGhlIFBDSQo+ID4g PiA+IGNvcmUgcGF5IGF0dGVudGlvbiBpdC4gIFRoYXQgd291bGQgYmUgdGhlIGJlc3Qgc29sdXRp b24gYmVjYXVzZSBpdAo+ID4gPiA+IHdvdWxkbid0IHJlcXVpcmUgVGVncmEtc3BlY2lmaWMgY29k ZS4KPiA+ID4gCj4gPiA+IEhlcmUgaXMgdGhlIG91dHB1dCBvZiAnbHNwY2kgdnZ4eHgnIGZvciBv bmUgb2YgVGVncmExOTQncyByb290IHBvcnRzLgo+ID4gCj4gPiBUaGFua3MhCj4gPiAKPiA+IFRo aXMgcG9ydCBhZHZlcnRpc2VzIGJvdGggTVNJIGFuZCBNU0ktWCwgYW5kIG5laXRoZXIgb25lIGlz IGVuYWJsZWQuCj4gPiBUaGlzIHBhcnRpY3VsYXIgcG9ydCBkb2Vzbid0IGhhdmUgYSBzbG90LCBz byBob3RwbHVnIGlzbid0IGFwcGxpY2FibGUKPiA+IHRvIGl0Lgo+ID4gCj4gPiBCdXQgaWYgSSB1 bmRlcnN0YW5kIGNvcnJlY3RseSwgaWYgTVNJIG9yIE1TSS1YIHdlcmUgZW5hYmxlZCBhbmQgdGhl Cj4gPiBwb3J0IGhhZCBhIHNsb3QsIHRoZSBwb3J0IHdvdWxkIGdlbmVyYXRlIE1TSS9NU0ktWCBo b3RwbHVnIGludGVycnVwdHMuCj4gPiBCdXQgUE1FIGFuZCBBRVIgZXZlbnRzIHdvdWxkIHN0aWxs IGNhdXNlIElOVHggaW50ZXJydXB0cyAoZXZlbiB3aXRoCj4gPiBNU0kgb3IgTVNJLVggZW5hYmxl ZCkuCj4gPiAKPiA+IERvIEkgaGF2ZSB0aGF0IHJpZ2h0PyAgSSBqdXN0IHdhbnQgdG8gbWFrZSBz dXJlIHRoYXQgdGhlIHJlYXNvbiBmb3IKPiA+IFBNRSBiZWluZyBJTlR4IGlzIGEgcGVybWFuZW50 IGhhcmR3YXJlIGNob2ljZSBhbmQgdGhhdCBpdCdzIG5vdAo+ID4gcmVsYXRlZCB0byBNU0kgYW5k IE1TSS1YIGN1cnJlbnRseSBiZWluZyBkaXNhYmxlZC4KPgo+IFllcy4gVGhhdHMgcmlnaHQuIEl0 cyBoYXJkd2FyZSBjaG9pY2UgdGhhdCBvdXIgaGFyZHdhcmUgZW5naW5lZXJzIG1hZGUgdG8KPiB1 c2UgSU5UeCBmb3IgUE1FIGluc3RlYWQgb2YgTVNJIGlycmVzcGVjdGl2ZSBvZiBNU0kvTVNJLVgg ZW5hYmxlZC9kaXNhYmxlZAo+IGluIHRoZSByb290IHBvcnQuCgpIZXJlIGFyZSBtb3JlIHNwZWMg cmVmZXJlbmNlcyB0aGF0IHNlZW0gYXBwbGljYWJsZToKCiAgLSBQQ0llIHI0LjAsIHNlYyA3Ljcu MS4yIChNZXNzYWdlIENvbnRyb2wgUmVnaXN0ZXIgZm9yIE1TSSkgc2F5czoKCiAgICAgIE1TSSBF bmFibGUg4oCTIElmIFNldCBhbmQgdGhlIE1TSS1YIEVuYWJsZSBiaXQgaW4gdGhlIE1TSS1YCiAg ICAgIE1lc3NhZ2UgQ29udHJvbCByZWdpc3RlciAoc2VlIFNlY3Rpb24gNy45LjIpIGlzIENsZWFy LCB0aGUKICAgICAgRnVuY3Rpb24gaXMgcGVybWl0dGVkIHRvIHVzZSBNU0kgdG8gcmVxdWVzdCBz ZXJ2aWNlIGFuZCBpcwogICAgICBwcm9oaWJpdGVkIGZyb20gdXNpbmcgSU5UeCBpbnRlcnJ1cHRz LgoKICAtIFBDSWUgcjQuMCwgc2VjIDcuNy4yLjIgKE1lc3NhZ2UgQ29udHJvbCBSZWdpc3RlciBm b3IgTVNJLVgpIHNheXM6CgogICAgICBNU0ktWCBFbmFibGUg4oCTIElmIFNldCBhbmQgdGhlIE1T SSBFbmFibGUgYml0IGluIHRoZSBNU0kgTWVzc2FnZQogICAgICBDb250cm9sIHJlZ2lzdGVyIChz ZWUgU2VjdGlvbiA2LjguMS4zKSBpcyBDbGVhciwgdGhlIEZ1bmN0aW9uIGlzCiAgICAgIHBlcm1p dHRlZCB0byB1c2UgTVNJLVggdG8gcmVxdWVzdCBzZXJ2aWNlIGFuZCBpcyBwcm9oaWJpdGVkIGZy b20KICAgICAgdXNpbmcgSU5UeCBpbnRlcnJ1cHRzIChpZiBpbXBsZW1lbnRlZCkuCgpJIHJlYWQg dGhhdCB0byBtZWFuIGEgZGV2aWNlIGlzIHByb2hpYml0ZWQgZnJvbSB1c2luZyBNU0kvTVNJLVgg Zm9yCnNvbWUgaW50ZXJydXB0cyBhbmQgSU5UeCBmb3Igb3RoZXJzLiAgU2luY2UgVGVncmExOTQg Y2Fubm90IHVzZQpNU0kvTVNJLVggZm9yIFBNRSwgaXQgc2hvdWxkIHVzZSBJTlR4IGZvciAqYWxs KiBpbnRlcnJ1cHRzLiAgVGhhdAptYWtlcyB0aGUgTVNJL01TSS1YIENhcGFiaWxpdGllcyBzdXBl cmZsdW91cywgYW5kIHRoZXkgc2hvdWxkIGJlCm9taXR0ZWQuCgpJZiB3ZSBzZXQgcGRldi0+bm9f bXNpIGZvciBUZWdyYTE5NCwgd2UnbGwgYXZvaWQgTVNJL01TSS1YIGNvbXBsZXRlbHksCnNvIHdl J2xsIGFzc3VtZSAqYWxsKiBpbnRlcnJ1cHRzIGluY2x1ZGluZyBob3RwbHVnIHdpbGwgYmUgSU5U eC4gIFdpbGwKdGhhdCB3b3JrPwoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX18KbGludXgtYXJtLWtlcm5lbCBtYWlsaW5nIGxpc3QKbGludXgtYXJtLWtlcm5l bEBsaXN0cy5pbmZyYWRlYWQub3JnCmh0dHA6Ly9saXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4v bGlzdGluZm8vbGludXgtYXJtLWtlcm5lbAo=