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 882BE1373; Sun, 19 Oct 2025 00:04:50 +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=1760832292; cv=none; b=H4YfrTCq9HkHScBz52/KtK+xXtgjUBFBWvb5vU/VeZLEmrOSl1xA09umYg0sGwHmWobsQhUGkl5Y+ESFILH1iLNWCC3rRVNqY/TB3zpRxVTf72mRRv5FdUdxYuLzY2/l7rB6qkF5OWY+qHzxhZExeUkQWsiFIJFz0QURj+ptUiE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760832292; c=relaxed/simple; bh=NIlHXsTrn95hUwIwQiqLjVMv/ZLorBcbB6zrOrzvKRo=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=azlLtUvIldOUCNdMWB+Oarka9+d9b0tA9s4MGjCLArulDOHl6wnYz+nChXHlBIvapq/sg/2GUSAKEYWmCD1zBfYF/YGiCZnN6r399oUkorQwuReLX2MYdgqR3IE929Zt3nLutYYwb6WM4cWSO03ZyvsZq82z2VDlekfHDvetnNM= 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=AcN5Xqb1; 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="AcN5Xqb1" 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=rz0DjI9FG3R+Vf1dNEL5GbVU6jXA/C1j8hwA+dUf/6I=; b=AcN5Xqb1JNtWQtEk5ZUe7Vs44j z6+QascX8RZXSMzyNmZzlFs0g6XLvpMzTZ0U8eTgVmWGTWkCOapk0xir30PnWmjZ3UOLRQTKoWVuS ukLu99pJOm6qI3+yfv+f7nNyf4DISn160d2zMZr8VTYh9aVfCTZXUGhortzxREz4zatY=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1vAGu2-00BP9M-KF; Sun, 19 Oct 2025 02:04:02 +0200 Date: Sun, 19 Oct 2025 02:04:02 +0200 From: Andrew Lunn To: "Russell King (Oracle)" Cc: Inochi Amaoto , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Chen Wang , Maxime Coquelin , Alexandre Torgue , Han Gao , Icenowy Zheng , Vivian Wang , Yao Zi , netdev@vger.kernel.org, sophgo@lists.linux.dev, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Yixun Lan , Longbin Li Subject: Re: [PATCH] net: stmmac: dwmac-sophgo: Add phy interface filter Message-ID: <370d13b7-bba8-449d-9050-e0719d20b57c@lunn.ch> References: <20251017011802.523140-1-inochiama@gmail.com> <34fcc4cd-cd3d-418a-8d06-7426d2514dee@lunn.ch> 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: > "rgmii-id" doesn't mean "there is a delay _somewhere_ in the system". > It's supposed to mean that the PHY should add delays on both tx and > rx paths. When passed to the PHY it means that. However, DT describes the hardware, the PCB. "rgmii-id" means the PCB does not provide the delays. So the MAC/PHY combination needs to add the delays. We normally have the PHY provide the delays, so the phy-mode is normally passed straight to the PHY. However, if the MAC is adding a delay, which it is in this case, in one direction and cannot be turned off, the value passed to the PHY needs to reflect this, to avoid double delays. And because the MAC delay cannot be turned off, it means there are PCB designs which don't work, double delays. So it would be nice not to list them in the binding. Andrew