netdev - Re: [PATCH V2 03/12] net-next: mediatek: add embedded switch driver (ESW)

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <56D07C82.2040204@openwrt.org>
Date:	Fri, 26 Feb 2016 17:25:38 +0100
From:	Felix Fietkau <nbd@...nwrt.org>
To:	Andrew Lunn <andrew@...n.ch>, John Crispin <blogic@...nwrt.org>
Cc:	"David S. Miller" <davem@...emloft.net>, netdev@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	linux-mediatek@...ts.infradead.org, linux-kernel@...r.kernel.org,
	Matthias Brugger <matthias.bgg@...il.com>,
	"Steven Liu (?????????)" <steven.liu@...iatek.com>,
	"Carlos Huang (?????????)" <Carlos.Huang@...iatek.com>,
	"Fred Chang (?????????)" <Fred.Chang@...iatek.com>
Subject: Re: [PATCH V2 03/12] net-next: mediatek: add embedded switch driver
 (ESW)

On 2016-02-26 16:18, Andrew Lunn wrote:
> On Fri, Feb 26, 2016 at 03:21:35PM +0100, John Crispin wrote:
>> The ESW is found in many of the old 100mbit MIPS based SoCs. it has 5
>> external ports, 1 cpu port and 1 further port that the internal HW
>> offloading engine connects to.
>> 
>> This driver is very basic and only provides basic init and irq support.
>> The SoC and switch core both have support for a special tag making DSA
>> support possible.
> 
> Hi Crispin
> 
> There was recently a discussion about adding switches without using
> DSA or switchdev. It was pretty much decided we would not accept such
> drivers.
For exactly this reason, the code does not provide any non-standard API
for allowing the user to configure the switch. The hardware needs to be
programmed with some defaults for the driver to be functional (since the
switch logic is built into the SoC).

In my opinion, leaving this part out does not make much sense and
neither does deferring the entire patch series until we have a
switchdev/DSA capable driver. This is just a starting point, which will
be turned into a proper driver with the right APIs later.

- Felix