From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pandora.armlinux.org.uk (pandora.armlinux.org.uk [78.32.30.218]) (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 A713D18B0F; Fri, 23 Jan 2026 12:16:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=78.32.30.218 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769170617; cv=none; b=FE9VMHD2BWVmaEYyTRVWk1uL5sJWobPfsg+IfEmY6Y5S1ti6HWHgI7edbsVYBfDZo5vV6oFHurXSDmqOYR3yFfdMRWE6mcPR+6DF3EeQLHIVx5Tm8NHWYoGwhGprHheAKb9aFG4d57DCmTxP7f28F4syFd5ZujDXSMV6QI+o+PE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769170617; c=relaxed/simple; bh=b24RI/D97T0GXR3dVAs7IIGT9wx0X7rDPh9+6D0S+yI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=HeWP63aPo3os/b4m/hSkRim+7b/qM3aGSvqCRZlJcQD8L4/BQhHWQBRS9zUzmcT7Q+/MLCu+GztXtWn+B0zWRYOY8FRTDRy2TX4IUSQqsxxspQJtit13WYesDTiAlGHXVxW5D1KMYatXZu8NKpfKfQAjjUeBO82tE77atgXfhIs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk; spf=none smtp.mailfrom=armlinux.org.uk; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b=rKs+SNfJ; arc=none smtp.client-ip=78.32.30.218 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=armlinux.org.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=armlinux.org.uk header.i=@armlinux.org.uk header.b="rKs+SNfJ" 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=ciuUlnrZS5dMX8iutfmJQM7hUgar0C9zX6IcKy5DxsE=; b=rKs+SNfJkE6RykLpqsax8M2byb B8GGQ0rzsHPaM0xNOc1e3vqxG5sSsZITV/UsTueaXX15tbtasGKaYebtrZwAszXhoIgxhKGhS5Hu8 AtKEhSQEbbjAa3Ky+SXMxY5QeaFLaSpnOSuZgMaPjnS1X/9di5Pjz31wd5B13gqlvqbG3/RLprs2P mZDyL4mYGKRqM3/HsA9cfec6AOmFsN5j55fDqu+xQAj6anKeHuoMuQyEIskMfKEK2D2whb++BWyBl SDFc0u91nfYece7ZaPbVBvKhDpVEx+gyvbIAQduh54bWDI6bvgvDi/3J7EtF1yPGuf8C48JztkmfO ECRWSAVg==; Received: from shell.armlinux.org.uk ([fd8f:7570:feb6:1:5054:ff:fe00:4ec]:57706) by pandora.armlinux.org.uk with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1vjG5n-000000001zU-2RGp; Fri, 23 Jan 2026 12:16:47 +0000 Received: from linux by shell.armlinux.org.uk with local (Exim 4.98.2) (envelope-from ) id 1vjG5l-00000000259-1Azj; Fri, 23 Jan 2026 12:16:45 +0000 Date: Fri, 23 Jan 2026 12:16:45 +0000 From: "Russell King (Oracle)" To: Christian Marangi Cc: Andrew Lunn , Heiner Kallweit , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [net-next PATCH v2 0/3] net: phy: as21xxx: toggle In Band feature support Message-ID: References: <20260123120117.10883-1-ansuelsmth@gmail.com> 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: <20260123120117.10883-1-ansuelsmth@gmail.com> Sender: Russell King (Oracle) [Please note: gmail.com has become unreliable for email delivery, google has too much power to decide what is spam and what isn't, with no route for appeal. please consider switching to a different email provider.] On Fri, Jan 23, 2026 at 01:00:28PM +0100, Christian Marangi wrote: > This is a new variant of the previous submitted patch adding a similar > feature. > > Old Aeonsemi Firmware permitted only to enable or disable In Band > support and it couldn't be disabled after (or there wasn't a > way to detect the current state of it) > > As suggested by Russell this was bad Implementation. Some talk > with Aeonsemi permitted to release a new firmware with correct > implementation. > > This series adds support for this if new firmware (1.9.1+) is > used. On the new firmware, 2 new IPC command are introduced > to GET the current state of DPC RA (Rate Adaption) or SET it. > (DPC RA is effectively In Band mode) > > It was verified on the same scenario and can confirm it works > as expected. (Airoha AN7581/AN7583 with and without In Band > mode) (If PCS is set to In Band and PHY isn't then no > connection, so it's easy to verify correct functionality of > this) > > The new firmware is currently submitted to linux-firmware > awaiting it to be merged. > > For old firmware to save on compatibility we still enable > In Band by default (this is what the current driver do) > > This was discovered to be needed in some scenario as is effectively > the most compatible featureset. > > On a BananaPi R4 Pro, one of the 2 AS21xxx PHY is connected to > one of the Switch port and such switch supports only In Band when > set to USXGMII (assuming the Switch expect an SFP module to be > attached where in absence of i2c or MDIO line In Band is always > required) Coupling the PHY's rate adaption with inband support, but not setting phydev->rate_matching anywhere in this driver seems wrong, and highly suspicious. I'm not sure what to think given what you've said above, it just seems completely wrong what has happened here. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!