From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DA9A6CA77 for ; Wed, 26 Jul 2023 11:58:56 +0000 (UTC) Received: from mail-wr1-x430.google.com (mail-wr1-x430.google.com [IPv6:2a00:1450:4864:20::430]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A0D54E7E for ; Wed, 26 Jul 2023 04:58:54 -0700 (PDT) Received: by mail-wr1-x430.google.com with SMTP id ffacd0b85a97d-3175f17a7baso2930732f8f.0 for ; Wed, 26 Jul 2023 04:58:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1690372733; x=1690977533; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=YJ91wGokauJt4h461pORCO4RNq/KJQrLD2WGJ0qohX4=; b=WfOT5xvfNh1iqk7syIg4kmyVDW1YhagEo9TzC/tD06pO4vrsQ4MCLgdQ3qubnkjPos 0MjcaOIshsAbJ3b0ZyQ4EFafw2UNgqwy/kpns0gZmHSGEmLrgfdQQJKd76IEsKjgxBI9 eRnQF2mGHQIc32YBZJX8cUx7Y9FLjzE+Zn4+c2OkS6qsoSdvOk1660qLAHshT6VWCoyO I0cQx01jwCs2sqioRIsoBWNJHSKxYRH/pwlyN8iIMJOVjAmPkIPG6esoS8row+7hfJ3U 8Xks2c29yQRAaY6cVudPd/rghlkfdrhQGUCAFcoqnhHhgtF6CaYrUb6i9PJX3RfBTfg5 rM3w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1690372733; x=1690977533; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=YJ91wGokauJt4h461pORCO4RNq/KJQrLD2WGJ0qohX4=; b=U6ZazcRmoj3JBxN5cBhI1ZwFlAd8abtak1ew3Id4ZAJ24YK50BkKsnMansPQZZBrt5 +7EJOcMjXLUoDM/uNmRw53jP8yiOYchAQ7UA84jQyMIiR9uwP2o1XXbyus3XiR5UtLEd GCGl5pyuCPCkk3x55L2+8P27WL7AG4SM47Szw6CPQ86O01aRlxHRiO69SHhW6N8tQfNS 6o21eATvKstNP1nkl8snUm5ThsrriICbwj8LL3XogJKeC2wbbF7XxhZ2U0R0fio14+7N StGToLlesZ0agno6ZmN/1tDJk8OBpIWiTag6wmbsJ2zI+tIx2oAjXA0NlSEkTCnFlQzI bW0w== X-Gm-Message-State: ABy/qLaRxQazUfB6+YxZcX6KjtjPNMQ5MbhdbxbN/0haLsczHannlcnw yKzHFW3Y5PQ5ySAV3eDWcng= X-Google-Smtp-Source: APBJJlFBFaQBLrypfkvQRDfRCg0hi3rQU14s0ZY/E4YmE5tBxKcBDLE/uZ5R5xTim3l+zb9eZtCMbg== X-Received: by 2002:a5d:5707:0:b0:316:f06c:f07 with SMTP id a7-20020a5d5707000000b00316f06c0f07mr1132298wrv.64.1690372732766; Wed, 26 Jul 2023 04:58:52 -0700 (PDT) Received: from skbuf ([188.25.175.105]) by smtp.gmail.com with ESMTPSA id m12-20020adff38c000000b003145559a691sm19675103wro.41.2023.07.26.04.58.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 26 Jul 2023 04:58:52 -0700 (PDT) Date: Wed, 26 Jul 2023 14:58:49 +0300 From: Vladimir Oltean To: Andrew Lunn Cc: Shenwei Wang , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Maxime Coquelin , Shawn Guo , NXP Linux Team , Russell King , Giuseppe Cavallaro , Alexandre Torgue , Jose Abreu , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, imx@lists.linux.dev, Frank Li Subject: Re: [PATCH] net: stmmac: dwmac-imx: pause the TXC clock in fixed-link Message-ID: <20230726115849.ljzczotegiqlvmi6@skbuf> References: <20230725194931.1989102-1-shenwei.wang@nxp.com> <93ffd7a5-2479-4726-b26a-aab10ac09d14@lunn.ch> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <93ffd7a5-2479-4726-b26a-aab10ac09d14@lunn.ch> X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM, RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Hi Andrew, On Wed, Jul 26, 2023 at 10:32:00AM +0200, Andrew Lunn wrote: > On Tue, Jul 25, 2023 at 02:49:31PM -0500, Shenwei Wang wrote: > > When using a fixed-link setup, certain devices like the SJA1105 require a > > small pause in the TXC clock line to enable their internal tunable > > delay line (TDL). > > The SJA1105 has the problem, so i would expect it to be involved in > the solution. Otherwise, how is this going to work for other MAC > drivers? > > Maybe you need to expose a common clock framework clock for the TXC > clock line, which the SJA1105 can disable/enable? That then makes it > clear what other MAC drivers need to do. > > Andrew > The delicate nature of the SJA1105 bug is that as far as I understand, the switch is not aware of the fact that its RGMII delay line went out of whack. Its port MII status registers say that they're okay. Also, if I understand Shenwei's workaround procedure, it deals more with "prevention" than with "recovery". I'm not sure that (reliable) recovery is possible. I'm trying to gather more data from NXP colleagues.