From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754755Ab3A2QBk (ORCPT ); Tue, 29 Jan 2013 11:01:40 -0500 Received: from mail.free-electrons.com ([94.23.35.102]:35553 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751522Ab3A2QBi (ORCPT ); Tue, 29 Jan 2013 11:01:38 -0500 Date: Tue, 29 Jan 2013 17:01:31 +0100 From: Thomas Petazzoni To: Florian Fainelli Cc: davem@davemloft.net, Grant Likely , Rob Herring , Rob Landley , Jason Cooper , Andrew Lunn , Russell King , Benjamin Herrenschmidt , Paul Mackerras , Lennert Buytenhek , Greg Kroah-Hartman , devicetree-discuss@lists.ozlabs.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, netdev@vger.kernel.org Subject: Re: [PATCH 5/5] mv643xx_eth: convert to use the Marvell Orion MDIO driver Message-ID: <20130129170131.7964a110@skate> In-Reply-To: <1359473048-26551-6-git-send-email-florian@openwrt.org> References: <1359473048-26551-1-git-send-email-florian@openwrt.org> <1359473048-26551-6-git-send-email-florian@openwrt.org> Organization: Free Electrons X-Mailer: Claws Mail 3.9.0 (GTK+ 2.24.10; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Dear Florian Fainelli, On Tue, 29 Jan 2013 16:24:08 +0100, Florian Fainelli wrote: > This patch converts the Marvell MV643XX ethernet driver to use the > Marvell Orion MDIO driver. As a result, PowerPC and ARM platforms > registering the Marvell MV643XX ethernet driver are also updated to > register a Marvell Orion MDIO driver. This driver voluntarily overlaps > with the Marvell Ethernet shared registers because it will use a subset > of this shared register (shared_base + 0x4 - shared_base + 0x84). The > Ethernet driver is also updated to look up for a PHY device using the > Orion MDIO bus driver. > > Signed-off-by: Florian Fainelli > --- > arch/arm/plat-orion/common.c | 84 +++++++++++-- In this file, there was one "MV643XX_ETH_SHARED_NAME" platform_device registered for each network interface. Why? If the driver is shared, isn't the whole idea to register it only once? In any case, one of the idea of separating the mvmdio driver from the mvneta driver in the first place is that there should be only one instance of the mvmdio device, even if there are multiple network interfaces. The reason is that from a HW point of the view, the MDIO unit is shared between the network interfaces. If you look at armada-370-xp.dtsi, there is only one mvmdio device registered, and two network interfaces (using the mvneta driver) that are registered (and actually up to four network interfaces can exist, they are added by some other .dtsi files depending on the specific SoC). So I don't think there should be one instance of the mvmdio per network interface. Also, I am wondering what's left in this MV643XX_ETH_SHARED_NAME driver once the MDIO stuff has been pulled out in a separate driver? I think the whole point of this work should be to get rid of this MV643XX_ETH_SHARED_NAME driver, no? Thanks, Thomas -- Thomas Petazzoni, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com