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=-4.0 required=3.0 tests=BAYES_00,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 EEE03C4338F for ; Thu, 12 Aug 2021 15:26:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CCF14610A5 for ; Thu, 12 Aug 2021 15:26:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238023AbhHLP1K (ORCPT ); Thu, 12 Aug 2021 11:27:10 -0400 Received: from mail.kernel.org ([198.145.29.99]:40316 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232854AbhHLP1J (ORCPT ); Thu, 12 Aug 2021 11:27:09 -0400 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (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 65506610A4; Thu, 12 Aug 2021 15:26:44 +0000 (UTC) Received: from sofa.misterjones.org ([185.219.108.64] helo=why.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1mECbS-004a9P-6o; Thu, 12 Aug 2021 16:26:42 +0100 Date: Thu, 12 Aug 2021 16:26:41 +0100 Message-ID: <87v94a8z0u.wl-maz@kernel.org> From: Marc Zyngier To: Thierry Reding Cc: Matteo Croce , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Giuseppe Cavallaro , Alexandre Torgue , "David S. Miller" , Jakub Kicinski , Palmer Dabbelt , Paul Walmsley , Drew Fustini , Emil Renner Berthing , Jon Hunter , Will Deacon Subject: Re: [PATCH net-next] stmmac: align RX buffers In-Reply-To: References: <20210614022504.24458-1-mcroce@linux.microsoft.com> <871r71azjw.wl-maz@kernel.org> <87pmuk9ku9.wl-maz@kernel.org> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/27.1 (x86_64-pc-linux-gnu) MULE/6.0 (HANACHIRUSATO) MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: thierry.reding@gmail.com, mcroce@linux.microsoft.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, peppe.cavallaro@st.com, alexandre.torgue@foss.st.com, davem@davemloft.net, kuba@kernel.org, palmer@dabbelt.com, paul.walmsley@sifive.com, drew@beagleboard.org, kernel@esmil.dk, jonathanh@nvidia.com, will@kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, 12 Aug 2021 15:29:06 +0100, Thierry Reding wrote: > > On Wed, Aug 11, 2021 at 02:23:10PM +0100, Marc Zyngier wrote: [...] > > I love this machine... Did this issue occur with the Denver CPUs > > disabled? > > Interestingly I've been doing some work on a newer device called Jetson > TX2 NX (which is kind of a trimmed-down version of Jetson TX2, in the > spirit of the Jetson Nano) and I can't seem to reproduce these failures > there (tested on next-20210812). > > I'll go dig out my Jetson TX2 to run the same tests there, because I've > also been using a development version of the bootloader stack and > flashing tools and all that, so it's possible that something was fixed > at that level. I don't think I've ever tried disabling the Denver CPUs, > but then I've also never seen these issues myself. > > Just out of curiosity, what version of the BSP have you been using to > flash? I've only used the BSP for a few weeks when I got the board last year. The only thing I use from it is u-boot to chainload an upstream u-boot, and boot Debian from there. > One other thing that I ran into: there's a known issue with the PHY > configuration. We mark the PHY on most devices as "rgmii-id" on most > devices and then the Marvell PHY driver needs to be enabled. Jetson TX2 > has phy-mode = "rgmii", so it /should/ work okay. > > Typically what we're seeing with that misconfiguration is that the > device fails to get an IP address, but it might still be worth trying to > switch Jetson TX2 to rgmii-id and using the Marvell PHY, to see if that > improves anything. I never failed to get an IP address. Overall, networking has been solid on this machine until this patch. I'll try and mess with this when I get time, but that's probably going to be next week now. [...] > > That'd be pretty annoying. Do you know if the Ethernet is a coherent > > device on this machine? or does it need active cache maintenance? > > I don't think Ethernet is a coherent device on Tegra186. I think > Tegra194 had various improvements with regard to coherency, but most > devices on Tegra186 do need active cache maintenance. > > Let me dig through some old patches and mailing list threads. I vaguely > recall prototyping a patch that did something special for outer cache > flushing, but that may have been Tegra132, not Tegra186. I also don't > think we ended up merging that because it turned out to not be needed. ARMv8 forbid any sort of *visible* outer cache, so I really hope this is not required. We wouldn't be able to support it. Thanks, M. -- Without deviation from the norm, progress is not possible.