Hi all, I'm working on mainlining of NXP1102 PHY (BroadR Reach/802.3bw) support. Basic functionality is working and support with mainline kernel. Now it is time to extend it. According to the specification, each PHY can be master or slave. The HW can be pre configured via bootstrap pins or fuses to have a default configuration. But in some cases we still need to be able to configure the PHY in a different mode: -------------------------------------------------------------------------------- http://www.ieee802.org/3/1TPCESG/public/BroadR_Reach_Automotive_Spec_V3.0.pdf 6.1 MASTER-SLAVE configuration resolution All BroadR-Reach PHYs will default to configure as SLAVE upon power up or reset until a management system (for example, processor/microcontroller) configures it to be MASTER. MASTER-SLAVE assignment for each link configuration is necessary for establishing the timing control of each PHY. 6.2 PHY-Initialization Both PHYs sharing a link segment are capable of being MASTER or SLAVE. In IEEE 802.3-2012, MASTER-SLAVE resolution is attained during the Auto-Negotiation process (see IEEE 802.3-2012 Clause 28). However, the latency for this process is not acceptable for automotive application. A forced assignment scheme is employed depending on the physical deployment of the PHY within the car. This process is conducted at the power-up or reset condition. The station management system manually configures the BroadR-Reach PHY to be MASTER (before the link acquisition process starts) while the link partner defaults to SLAVE (un-managed). -------------------------------------------------------------------------------- Should phylink be involved in this configuration? What's the proper user space interface to use for this kind of configuration? ethtool or ip comes into mind. Further having a Device Tree property to configure a default mode to overwrite the boot strap pins would be nice to have. Regards, Oleksij -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
