From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Fainelli Subject: Re: [PATCH RFC 2/2] net: dsa: bcm_sf2: implement HW bridging operations Date: Thu, 19 Feb 2015 15:50:53 -0800 Message-ID: <54E676DD.9090003@gmail.com> References: <1424201196-4901-1-git-send-email-f.fainelli@gmail.com> <1424201196-4901-3-git-send-email-f.fainelli@gmail.com> <54E54EF3.9020802@gmail.com> <20150219055953.GA14247@roeck-us.net> <54E61CFB.3010109@gmail.com> <20150219174640.GA6897@roeck-us.net> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, davem@davemloft.net, vivien.didelot@savoirfairelinux.com, jerome.oufella@savoirfairelinux.com, andrew@lunn.ch, cphealy@gmail.com To: Guenter Roeck Return-path: Received: from mail-pd0-f179.google.com ([209.85.192.179]:46585 "EHLO mail-pd0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753862AbbBSXvL (ORCPT ); Thu, 19 Feb 2015 18:51:11 -0500 Received: by pdjy10 with SMTP id y10so3328383pdj.13 for ; Thu, 19 Feb 2015 15:51:10 -0800 (PST) In-Reply-To: <20150219174640.GA6897@roeck-us.net> Sender: netdev-owner@vger.kernel.org List-ID: On 19/02/15 09:46, Guenter Roeck wrote: > On Thu, Feb 19, 2015 at 09:27:23AM -0800, Florian Fainelli wrote: >> On 18/02/15 21:59, Guenter Roeck wrote: >>> On Wed, Feb 18, 2015 at 06:48:19PM -0800, Florian Fainelli wrote: >>>> On 17/02/15 11:26, Florian Fainelli wrote: >>>>> Update the Broadcom Starfighter 2 switch driver to implement the >>>>> join/leave/stp_update callbacks required for basic hardware bridging >>>>> support. >>>>> >>>>> There is not much to be done at the driver level but translating the >>>>> STP state from Linux to their HW values. >>>>> >>>>> Joining a bridge means that the joining port and the other port members >>>>> need to be in the same VLAN membership as the CPU, while leaving the >>>>> bridge puts the port back into a separate VLAN membership with only the >>>>> CPU. >>>> >>>> I found a couple additional issues while testing: >>>> >>>> - manipulating UP/DOWN state of interfaces that are part of a bridge >>>> would not restore their bridge membership >>>> >>>> - removing an interface from a bridge and bringing it back up would >>>> leave it in blocked state >>>> >>> Is this a problem with your implementation for sf2 or a generic problem >>> with the first patch, such as some missing state transitions ? >> >> This is more of a side effect of having HW (an Ethernet switch) that can >> really block a given port, based on last night's discussion with Roopa, >> we can either fix this at the DSA level (in our case) or better fix this >> at the bridge layer, I will propose a fix for this shortly. >> >>> >>> For sf2, you might have to set the port state as well as the bridge >>> association in the port_setup function. That is of course just a >>> wild guess. >> >> Right, that's what I ended up doing. Thanks! > > Great. > > Another question: How do you handle flushing the forwarding database ? > > My current code for mv88e6352 flushes the forwarding database for a bridge > group if the port association for that group changes (whenever a port joins > or leaves a group, or whenever the state of a port in a group changes). > There is, however, another situation where the forwarding database may > have to be flushed - essentially on each topology change. > > How do you handle this situation ? Is it a real problem or do I just > imagine that it is ? This is a real problem, for once I was working under the assumption that the SF2 hardware was doing an automatic FDB flushing, but after re-reading the documentation, this is not the case. My lab network does not have many stations and I certainly did not catch that case. -- Florian