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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 BCEDCC2D0E4 for ; Fri, 18 Dec 2020 10:13:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A304223437 for ; Fri, 18 Dec 2020 10:13:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389051AbgLRKNG (ORCPT ); Fri, 18 Dec 2020 05:13:06 -0500 Received: from mx2.suse.de ([195.135.220.15]:43808 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389031AbgLRKNF (ORCPT ); Fri, 18 Dec 2020 05:13:05 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 02F0EAC7B; Fri, 18 Dec 2020 10:12:23 +0000 (UTC) Date: Fri, 18 Dec 2020 11:12:21 +0100 From: Mian Yousaf Kaukab To: Rob Herring Cc: Vidya Sagar , lorenzo.pieralisi@arm.com, bhelgaas@google.com, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: dwc: tegra194: issue with card containing a bridge Message-ID: <20201218101221.GB52649@suse.de> References: <20201215102442.GA20517@suse.de> <9a8abc90-cf18-b0c8-3bcb-efbe03f0ca4c@nvidia.com> <20201215132504.GA20914@suse.de> <20201215154147.GA3885265@robh.at.kernel.org> <20201215205235.GC20914@suse.de> <20201217145857.GA3941403@robh.at.kernel.org> <20201217170635.GA52649@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20201217170635.GA52649@suse.de> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 17, 2020 at 06:06:35PM +0100, Mian Yousaf Kaukab wrote: > On Thu, Dec 17, 2020 at 08:58:57AM -0600, Rob Herring wrote: > > On Tue, Dec 15, 2020 at 09:52:35PM +0100, Mian Yousaf Kaukab wrote: > > > On Tue, Dec 15, 2020 at 09:41:47AM -0600, Rob Herring wrote: > > > > On Tue, Dec 15, 2020 at 02:25:04PM +0100, Mian Yousaf Kaukab wrote: > > > > > On Tue, Dec 15, 2020 at 05:45:59PM +0530, Vidya Sagar wrote: > > > > > > Thanks Mian for bringing it to our notice. > > > > > > Have you tried removing the dw_pcie_setup_rc(pp); call from pcie-tegra194.c > > > > > > file on top of linux-next? and does that solve the issue? > > > > > > > > > > > > diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c > > > > > > b/drivers/pci/controller/dwc/pcie-tegra194.c > > > > > > index 5597b2a49598..1c9e9c054592 100644 > > > > > > --- a/drivers/pci/controller/dwc/pcie-tegra194.c > > > > > > +++ b/drivers/pci/controller/dwc/pcie-tegra194.c > > > > > > @@ -907,7 +907,7 @@ static void tegra_pcie_prepare_host(struct pcie_port > > > > > > *pp) > > > > > > dw_pcie_writel_dbi(pci, CFG_TIMER_CTRL_MAX_FUNC_NUM_OFF, > > > > > > val); > > > > > > } > > > > > > > > > > > > - dw_pcie_setup_rc(pp); > > > > > > + //dw_pcie_setup_rc(pp); > > > > > I still see the same issue with this change. > > > > > Reverting b9ac0f9dc8ea works though. > > > > > > > > > > > > clk_set_rate(pcie->core_clk, GEN4_CORE_CLK_FREQ); > > > > > > > > > > > > I took a quick look at the dw_pcie_setup_rc() implementation and I'm not > > > > > > sure why calling it second time should create any issue for the enumeration > > > > > > of devices behind a switch. Perhaps I need to spend more time to debug that > > > > > > part. > > > > > > In any case, since dw_pcie_setup_rc() is already part of > > > > > > dw_pcie_host_init(), I think it can be removed from > > > > > > tegra_pcie_prepare_host() implemention. > > > > > > > > I think the 2nd time is making the link go down is my guess. Tegra was > > > > odd in that its start/stop link functions don't do link handling, so I > > > > didn't implement those functions and left the link handling in the Tegra > > > > driver. > > > > > > > > Can you try the below patch. It needs some more work as it breaks > > > > endpoint mode. > > > > [...] > > > > > Boot is ok with this patch. Some improvement in lspci as well: > > > > Some improvement? Meaning not completely working still? > > > > > # lspci > > > 0001:00:00.0 PCI bridge: NVIDIA Corporation Device 1ad2 (rev a1) > > > 0001:01:00.0 SATA controller: Marvell Technology Group Ltd. Device 9171 (rev 13) > > > 0005:00:00.0 PCI bridge: NVIDIA Corporation Device 1ad0 (rev a1) > > > 0005:01:00.0 PCI bridge: PLX Technology, Inc. Device 3380 (rev ab) > > > > This patch was closer to the original flow, but would not have worked if > > DLFE disabled mode was needed. > > > > Please give this patch a try: > Thank you for the patch! Initial results with it looks very promising. > I’ll get back to you tomorrow after running a few more tests. Rob, thank you for your efforts! This patch fixed the issue I was seeing. FWIW: Tested-by: Mian Yousaf Kaukab BR, Yousaf