From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from vps0.lunn.ch (vps0.lunn.ch [156.67.10.101]) (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 0A8F51D9592; Mon, 16 Dec 2024 23:40:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=156.67.10.101 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734392407; cv=none; b=Awir3Ozh4HukdgaCgnCN33Abr/Rl+TFxAvTIzayRjopP4iQcn/Ym3JYiAZu9Ebo7lMVJLBVR35JBpn3FmhNM1KPMYuh5KDeAaTTyXYKNkx4zP5IdORYlNktuJ1k/8R5Kv/bARk0oDS1rKDf5wWntTE8M0LzRgGgKnPA/x8h/WBk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734392407; c=relaxed/simple; bh=hwFTU+aDrAxRqtfNu17S8fajQDpZT6VQ2Qyi0VlXrWY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=a+Tm6v8aL/lu7s79IbbCaaH2zsXPx5GuUwlonbzSv/uDt8/iJMPWbW7uDeL7qIAxlc60Pcrrs1hCNMsW8f34VpQ7II3CaPpQosQ4cm3b6tNlQfB0IKKIA89DP5C8Sw1/sN9uiq0ef72IgtAK1s2uSgMBPGgSAPOpn3YsH07dk2c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lunn.ch; spf=pass smtp.mailfrom=lunn.ch; dkim=pass (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b=DiPyhbhF; arc=none smtp.client-ip=156.67.10.101 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lunn.ch Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lunn.ch Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b="DiPyhbhF" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Disposition:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:From:Sender:Reply-To:Subject: Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Content-Disposition:In-Reply-To:References; bh=iVv5Akk0Lsj+pfryBSdDLl6/RTTbH+SqQKI/EOqGTdM=; b=DiPyhbhFKha79zYSAZ1EtslcQg X0XykpcPfWcn862SSUyRZKiZ9DHEpXq1xKnLFQ1gdCVa2Ay0bofvE76pFMM7mMK3LOmg1iGKPaLOk Byw2hENG2fuQCQ8Dn+8YjVJJ38BC0a3llQw7PWtKu0+qfYKX4Q1v9fTAvcERiRGfeGIo=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1tNKgX-000m6m-KV; Tue, 17 Dec 2024 00:39:33 +0100 Date: Tue, 17 Dec 2024 00:39:33 +0100 From: Andrew Lunn To: Tarun Alle Cc: arun.ramadoss@microchip.com, UNGLinuxDriver@microchip.com, hkallweit1@gmail.com, linux@armlinux.org.uk, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next v2 2/2] net: phy: microchip_t1: Auto-negotiation support for LAN887x Message-ID: References: <20241216155830.501596-1-Tarun.Alle@microchip.com> <20241216155830.501596-3-Tarun.Alle@microchip.com> Precedence: bulk X-Mailing-List: linux-kernel@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: <20241216155830.501596-3-Tarun.Alle@microchip.com> On Mon, Dec 16, 2024 at 09:28:30PM +0530, Tarun Alle wrote: > Adds auto-negotiation support for lan887x T1 phy. After this commit, > by default auto-negotiation is on and default advertised speed is 1000M. So i asked about the implications of this. I would of expected something like: This will break any system which expects forced behaviour, without actually configuring forced behaviour both on the local system and where the link partner is expecting forced configuration, not autoneg. I think we also need some more details about the autoneg in the commit message. When used against a standards conforming 100M PHY, negotiation will fail by default, because this PHY is not conformant with 100M, or 1G autoneg. I don't like you are going to cause regressions, especially when you have decided regressions are worth it for a half broken autoneg. I actually think it should default to fixed, as it is today. Maybe with the option to enable the broken autoneg. This is different to all PHYs we have today, but we try hard to avoid regressions. What are the plans for this PHY? Will there be a new revision soon which fixes the broken autoneg? Maybe you should forget about autoneg for this revision of this PHY, it is too broken, and wait for the next revision which actually conforms to the standard? Andrew