Hi Detlev,
-----Ursprüngliche Nachricht----- Von: Detlev Zundel [mailto:dzu@denx.de] Gesendet: Dienstag, 27. September 2011 16:28 An: Bernhard Kaindl Cc: Schneider, Kolja; u-boot@lists.denx.de Betreff: Re: [U-Boot] MPC512x FEC/MII
Hi Bernhard,
we also get broken output from mii_cmd when the commit which you
show
below is applied, reverting it helps.
Hardware: Our own MPC5121ADS-based board and the MPC5121ADS
development
board.
The commit is titled:
mpc512x_fec: Move PHY initialization from probe into init routin This saves the autonegotation delay when not using ethernet in U-Boot",
This exactly what it does, the effect is no suprise at all:
Of course, the move of the PHY init from the fec_probe (executed before the u-boot prompt appears) to the fec_init (called only and every time a new network command is executed) has the effect which we see:
The PHY is only initialized while a network command (such as dhcp, tftp, ...) is being executed.
Well, this is actually in line with the U-Boot design principles of initializing a device only if its needed[1]. This principle was disregarded regularly in the past and so it seems kind of naturla that "fixing" it results in changes of behaviour. We should however fix the fallout rather than going back to violating the principles.
If the mii routines need initializations, then they should ensure that they have been done.
This really is a shame as the mii tools are quite helpful for debugging/hardware verification. If the mii-command performs a re-initialisation each time they are invoked, they are probably close to useless (as one would need several commands to perform certain tasks...).
However I understand this is something that is not quite in the scope of a bootloader. As long as an easy workaround is available...
:) Kolja