netdev - Problem with am335x (cpsw) MDIO state machine

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>] [day] [month] [year] [list]

Date:	Fri, 22 Nov 2013 17:06:08 +0100
From:	Stefan Roese <stefan.roese@...il.com>
To:	Mugunthan V N <mugunthanvnm@...com>
CC:	"netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: Problem with am335x (cpsw) MDIO state machine

Hi All!

I'm currently struggling with the MDIO interface of the am335x SoC. As
its state machine continuously communicates with the potentially
available PHY devices (0...31). To determine the link status etc. But
I'm trying to communicate with am SMSC9303 switch via this MDIO
interface. It has 32bit registers organized as 2 16bit registers. These
registers need to be accessed back-to-back. Without any other frame in
between. And this is often interrupted (disturbed) by these state
machines polling frames.

Has anyone ever tried to work in this SoC with this MDIO state machine
disabled? I tried this by clearing the ENABLE bit in the MDIOCONTROL
register after each transaction. But this doesn't seem to work
(resulting in timeouts etc)?

Has anybody ever tried anything like this?

Thanks,
Stefan
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html