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=-5.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 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 A7633C47089 for ; Wed, 26 May 2021 15:46:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 848AF613D7 for ; Wed, 26 May 2021 15:46:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232913AbhEZPsQ (ORCPT ); Wed, 26 May 2021 11:48:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51290 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235436AbhEZPsP (ORCPT ); Wed, 26 May 2021 11:48:15 -0400 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [IPv6:2001:4d48:ad52:32c8:5054:ff:fe00:142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 026C7C061574 for ; Wed, 26 May 2021 08:46:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=armlinux.org.uk; s=pandora-2019; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=FQ3+qLJeDs/yhLVDx0p9Cm5eCT5k0xUV+GC0JxJ+LPo=; b=TwdKnwRPn1DH7N8z4rBBLB8VK cSCFInNRrgQFGHGbA/7z9lmF8umljbE17g3UQ81aQLvm0fvCPDyNTXo2726sZunQu5dW5XUTBY2g1 HCD7hnRD3QoA7BlxdVOzjFtX/I5XzMuFFr+YNNX/2gJE4HRCqTNMDObmvJ9nYnCo9sowfQdpuJByf 7SkdI4bRqX+6WRk9+oh+2E1nUEcLWGVunkm3F5fN+3rB5aPqrUwRO32bNsixsMl/zvkWp6uNMyAX+ eUJXceUfc4m7vvdv9MMXRLz67uMxtfIyWmmXh0YLvPd5Es/WVe4QnnnUXL68iHgh/gNEU0j4qKK0V jTD8CJ8/w==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:44384) by pandora.armlinux.org.uk with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1llvk1-0005sw-Qh; Wed, 26 May 2021 16:46:41 +0100 Received: from linux by shell.armlinux.org.uk with local (Exim 4.92) (envelope-from ) id 1llvk1-0002wa-J5; Wed, 26 May 2021 16:46:41 +0100 Date: Wed, 26 May 2021 16:46:41 +0100 From: "Russell King (Oracle)" To: Vladimir Oltean Cc: Jakub Kicinski , "David S. Miller" , netdev@vger.kernel.org, Florian Fainelli , Andrew Lunn , Vivien Didelot , Heiner Kallweit Subject: Re: [RFC PATCH v2 linux-next 13/14] net: dsa: sja1105: expose the SGMII PCS as an mdio_device Message-ID: <20210526154641.GJ30436@shell.armlinux.org.uk> References: <20210526135535.2515123-1-vladimir.oltean@nxp.com> <20210526135535.2515123-14-vladimir.oltean@nxp.com> <20210526152911.GH30436@shell.armlinux.org.uk> <20210526154102.dlp2clwqncadna2v@skbuf> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210526154102.dlp2clwqncadna2v@skbuf> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: Russell King (Oracle) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wed, May 26, 2021 at 06:41:02PM +0300, Vladimir Oltean wrote: > On Wed, May 26, 2021 at 04:29:11PM +0100, Russell King (Oracle) wrote: > > On Wed, May 26, 2021 at 04:55:34PM +0300, Vladimir Oltean wrote: > > > Since we touch all PCS accessors again, now it is a good time to check > > > for error codes from the hardware access as well. We can't propagate the > > > errors very far due to phylink returning void for mac_config and > > > mac_link_up, but at least we print them to the console. > > > > phylink doesn't have much option on what it could do if we error out at > > those points - I suppose we could print a non-specific error and then > > lock-out the interface in a similar way that phylib does, but to me that > > seems really unfriendly if you're remotely accessing a box and the error > > is intermittent. > > I would like to have intermittent errors at this level logged, because > to me they would be quite unexpected and I would like to have some rope > to pull while debugging - an error code, something. > > If there's an error of any sort, the interface won't be fully > initialized anyway, so not functional. > > The reason why I added error checking in this patch is because I was > working on the MDIO bus accessors and I wanted to make sure that the > errors returned there are propagated somewhere. Yes, makes sense there, but doesn't make sense if one is using the MMIO accessors and have no errors to check... My argument is - if you print an error at the lower levels, you can be more specific about what failed. If you do it in phylink, you can only say "oh, the blah_config() call failed" - which isn't particularly useful. Yes, we do this for some of the newly introduced methods, e.g. the pcs_config() method - and there all we can say is: if (err < 0) phylink_err(pl, "pcs_config failed: %pe\n", ERR_PTR(err)); -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!