[PATCH] MPC85XX TSEC driver: fix for mdio speed

Stefan Nickl Stefan.Nickl at kontron.com
Tue Jun 29 20:17:44 EST 2004


In gianfar_phy.c, the divisor for the MDIO interface to the PHYs
is set to a safe value as part of running a phy_cmd.
However, there is one MDIO transaction that happens before any command
is sent: reading the PHYs manufactuere identifier in get_phy_info.

This patch adds a "dummy command" to use the side effect of
phy_run_commands.

Background is that the initial revision of our hardware only works
reliably with the slowest divisor as long as the FEC PHY is the only
(MDIO) bus load. We kept reading slightly distorted ID from the FEC's
PHY when the 2 Marvells were not yet up.

--
Stefan Nickl
Kontron Modular Computers

-------------- next part --------------
A non-text attachment was scrubbed...
Name: gfar_mdiospeed.patch
Type: text/x-patch
Size: 493 bytes
Desc: not available
Url : http://ozlabs.org/pipermail/linuxppc-embedded/attachments/20040629/90a44f7a/attachment.bin 


More information about the Linuxppc-embedded mailing list