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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 84079C4828F for ; Sun, 4 Feb 2024 17:08:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc: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=U4d3lRQ+ywMUSxhsEgLIy35J6MHjR5owkJFbKhUA3UE=; b=J9O+Yci4hBblMFkGCbHskWdDrj xkqp6zDL+IoTvDDuscJBYCqp3F/PW4f+8cuXzJMgdNhsL4k/eHcuLilF18wSJoUgbgkt/U+y6TOMi GXotGxQLAhPloTD3mhwfMRc0gFtew7GFjILILQua74RGLFsKpybl92BTC8jMWtp9X0rn7B7rj0N+M il3yyp/jAxk3CUm4svM5hW+vDlKfvojlHCe9pm9fHtnwuUYEuh7VOD1URzuo84EAvp7qFcf+xqh51 8hu3fTbBBCUxBqaOhU6PqOLSEkjdojg/G88R71gBrU5CbEyj1ImT7eRIZEca5E7UxLlLvQF8yl5wg Fvb5xLUA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1rWfyU-00000001CgJ-1IBw; Sun, 04 Feb 2024 17:08:10 +0000 Received: from pandora.armlinux.org.uk ([2001:4d48:ad52:32c8:5054:ff:fe00:142]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1rWfyQ-00000001Cfm-1VhQ; Sun, 04 Feb 2024 17:08:07 +0000 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-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To: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=U4d3lRQ+ywMUSxhsEgLIy35J6MHjR5owkJFbKhUA3UE=; b=O23N4o9hua1bAJ5AUx0rkQ/4NH nHRZyTmutWAbbf9FljfiUtU6WWkEryEp5R+bpzo9Pk/QP6PY/T/9p0VIbkUJjdSUSO6bnnjNJ9RGj RXeexlnfDUlbauEzkG/glRz5aql0Wemp7ZnWq08Rx58XDPhNDCDOW1MuK7H8mgzGM6jVAo+0Eruiy Vh7Qm8Np+KNUsW0wFF7K5tPMkbrOYRG5EsjvImM5Mz+GoyngUkfvXGPK6ZdxDMMrNMaEBMwjUKWOp AohLh166OCDr3k8zCWRCLn9At8Mh2FdDpbikUa97+oAGUJjGNdWaxUcj8EJmfxMxZ42G+QDqHodNz TWq5y0SA==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:35158) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1rWfyD-0008Ai-2R; Sun, 04 Feb 2024 17:07:53 +0000 Received: from linux by shell.armlinux.org.uk with local (Exim 4.94.2) (envelope-from ) id 1rWfy9-0001vQ-VX; Sun, 04 Feb 2024 17:07:50 +0000 Date: Sun, 4 Feb 2024 17:07:49 +0000 From: "Russell King (Oracle)" To: =?utf-8?B?QXLEsW7DpyDDnE5BTA==?= Cc: Daniel Golle , DENG Qingfang , Sean Wang , Andrew Lunn , Florian Fainelli , Vladimir Oltean , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Matthias Brugger , AngeloGioacchino Del Regno , mithat.guner@xeront.com, erkin.bozoglu@xeront.com, Bartel Eerdekens , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org Subject: Re: [PATCH net-next v3 4/7] net: dsa: mt7530: move XTAL check to mt7530_setup() Message-ID: References: <20240202-for-netnext-mt7530-improvements-2-v3-0-63d5adae99ca@arinc9.com> <20240202-for-netnext-mt7530-improvements-2-v3-4-63d5adae99ca@arinc9.com> <5b744f7f-2f63-4219-a0e9-8f08267b1fdd@arinc9.com> <4fa2ff0d-2804-4a58-980f-162e62b3dc9c@arinc9.com> <850064fb-59c6-4e07-962a-6a213e9e7f90@arinc9.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <850064fb-59c6-4e07-962a-6a213e9e7f90@arinc9.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240204_090806_581000_FED33600 X-CRM114-Status: GOOD ( 51.99 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On Sun, Feb 04, 2024 at 07:51:49PM +0300, Arınç ÜNAL wrote: > On 4.02.2024 19:38, Russell King (Oracle) wrote: > > On Sun, Feb 04, 2024 at 06:55:14PM +0300, Arınç ÜNAL wrote: > > > On 4.02.2024 17:18, Russell King (Oracle) wrote: > > > > On Sun, Feb 04, 2024 at 04:55:40PM +0300, Arınç ÜNAL wrote: > > > > > This is not about laziness. This is before patch 2: > > > > > > > > > > phylink_mac_ops :: mac_config() -> dsa_port_phylink_mac_config() > > > > > -> dsa_switch_ops :: phylink_mac_config() -> mt753x_phylink_mac_config() > > > > > -> mt753x_mac_config() > > > > > -> mt753x_info :: mac_port_config() -> mt7530_mac_config() > > > > > -> mt7530_setup_port5() > > > > > -> mt753x_pad_setup() > > > > > -> mt753x_info :: pad_setup() -> mt7530_pad_clk_setup() > > > > > > > > > > This is after: > > > > > > > > > > phylink_mac_ops :: mac_config() -> dsa_port_phylink_mac_config() > > > > > -> dsa_switch_ops :: phylink_mac_config() -> mt753x_phylink_mac_config() > > > > > -> mt753x_mac_config() > > > > > -> mt753x_info :: mac_port_config() -> mt7530_mac_config() > > > > > -> mt7530_setup_port5() > > > > > -> mt7530_setup_port6() > > > > > > > > > > Patch 2 does not move mt7530_setup_port6() to be called from > > > > > phylink_mac_ops :: mac_config(), it already is. There is no valid reason to > > > > > reorder the patches. > > > > > > > > > > My response to Russell should've stated this instead of focusing on his > > > > > second sentence. > > > > > > > > This patch moves the test for a 20MHz crystal to mt7530_setup(), > > > > which is something that is entirely orthogonal to patch 2, which > > > > can be done cleanly (I've just applied the patches in the original > > > > order and then reordered them: > > > > > > > > 98c481f5d706 net: dsa: mt7530: do not clear config->supported_interfaces > > > > 93c6b53b17f4 net: dsa: mt7530: correct port capabilities of MT7988 > > > > c9c6d4c51a1d net: dsa: mt7530: simplify mt7530_setup_port6() and change to void > > > > adfa948253e0 net: dsa: mt7530: remove pad_setup function pointer > > > > 57e21e6c2fc0 net: dsa: mt7530: call port 6 setup from mt7530_mac_config() > > > > 959a0f9323c8 net: dsa: mt7530: move XTAL check to mt7530_setup() > > > > 856ab64a22ef net: dsa: mt7530: empty default case on mt7530_setup_port5() > > > > > > > > No problems. The end result is identical comparing the git tree at the > > > > original "move XTAL" patch with adfa948253e0. > > > > > > > > Now, if we look at "net: dsa: mt7530: remove pad_setup function pointer" > > > > we can see that yes, the pad_setup() method was called from mac_confing, > > > > but this is the exact contents of that patch removing the callsite: > > > > > > > > - mt753x_pad_setup(ds, state); > > > > > > > > This returns an integer, which may be an error code, which is ignored. > > > > Therefore, if the XTAL frequency check fires, and mt753x_pad_setup() > > > > returns an error, it is ignored today. > > > > > > > > After "net: dsa: mt7530: call port 6 setup from mt7530_mac_config()" > > > > the renamed pad_setup() method is now called from mac_config() thusly: > > > > > > > > + ret = mt7530_setup_port6(priv->ds, interface); > > > > + if (ret) > > > > + return ret; > > > > > > > > So now the error checks cause mt7530_mac_config() to return an error > > > > which in turn causes mt753x_mac_config() to fail, and therefore > > > > mt753x_phylink_mac_config() has different behaviour. > > > > > > > > So, patch 2 changes the driver behaviour in the case of a 20MHz XTAL, > > > > which is then changed again by patch 4. > > > > > > > > It would be better to have only one change of behaviour by moving > > > > patch 4 before patch 2. > > > > > > If the idea is to not bring any more error returns to mt753x_mac_config() > > > because the return code is actually checked for that, I should do a bit > > > more effort and put patch 5 before patch 2 as well, to live up to what you > > > originally requested. > > > > I assume you are referring to getting rid of the default case in > > mt7530_pad_clk_setup(). > > > > In patch "net: dsa: mt7530: call port 6 setup from mt7530_mac_config()" > > where you move this to be called from mt7530_mac_config(), you add it > > as: > > > > + } else if (port == 6) { > > + ret = mt7530_setup_port6(priv->ds, interface); > > + if (ret) > > + return ret; > > + } > > > > So it is only called for port 6. The switch within the called function > > deals with PHY_INTERFACE_MODE_RGMII and PHY_INTERFACE_MODE_TRGMII. > > Anything else results in the use of the default case, and thus > > returning an error. > > > > Since mt7530_mac_port_get_caps() does this for port 6: > > > > __set_bit(PHY_INTERFACE_MODE_RGMII, > > config->supported_interfaces); > > __set_bit(PHY_INTERFACE_MODE_TRGMII, > > config->supported_interfaces); > > > > mt7530_setup_port6() will only ever be called for these two modes, > > which means that the default case is unreachable, thus we will never > > execute that path, thus whether that path returns an error or not is > > completely irrelevant. > > > > The only case in mt7530_setup_port6() / mt7530_pad_clk_setup() which > > can today return an error is the XTAL check. > > > > Therefore, my suggestion makes complete sense, and there is no need > > to also move patch 5. > > Understood. I've already submitted v4 which moves patch 5. The remaining > benefit is that there're fewer code changes as I don't need to add an error > return for mt7530_setup_port6() and then remove it. I'm pretty sure netdev has a rule _not_ to submit the next version of a patch series if discussion about the previous is still ongoing... but I can't find any of the netdev rules in Documentation/networking anymore, and nothing stands out in Documentation/process... ah, Documentation/process/maintainer-netdev.rst, and here we are: "Make sure you address all the feedback in your new posting. Do not post a new version of the code if the discussion about the previous version is still ongoing, unless directly instructed by a reviewer." Discussion was still ongoing over this point, so ideally you should have waited instead of presenting a fait-accompli _during_ the ongoing discussion. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!