Hi Jocke, On Monday, August 23, 2010, Joakim Tjernlund <joakim.tjernl...@transmode.se> wrote: > Ben Warren <biggerbadder...@gmail.com> wrote on 2010/08/23 09:08:17: >> >> Hi Detlev, >> >> On 8/13/2010 1:20 AM, Detlev Zundel wrote: >> > Hi Jocke, >> > >> >>>> Instead of always performing an autoneg, check if the PHY >> >>>> already has a link and if it matches one of the requested >> >>>> modes. Initially only 100MbFD is optimized this way. >> >>> Isn't it about time that we think about _not_ stopping the ethernet >> >>> device after every transaction? >> >> Hi Detlev >> >> >> >> UEC does this already, my patch was to address the initial delay >> >> you get for the first transaction. Now my PHY based boards gets the link >> >> up just as quick as Fixed PHY for the first transaction. >> > Forgive me to not look into this any deeper, but do I understand you >> > correctly that you do this by essentially no-oping the eth_halt() >> > function? Isn't this then effectively violating what net.c expects the >> > device to do? >> > >> > I was thinking that net.c itself should not do this continous start/stop >> > thing as it has problems on many interfaces. On one ARM machine I've >> > again seen problems with the MAC address programming because the >> > eth_halt() resets the controller and so it forgets its address again. >> > Also the USB-CDC example where the _whole interface_ on the host side is >> > being torn down after each tftp transfer prompts me to think along this >> > line. >> > >> > So in effect I guess my response was rather a ping to Ben, sorry for >> > that ;) >> > >> Sorry for the delay on this. I'm all for changing the existing >> behavior. It seems to me that the only time we would ever want to wind >> an interface down is if we switch the active one (even then, I'm not >> sure). My world view is limited, but I can't imagine that even changing >> interfaces happens much in real world U-boot usage, that is the non-lab, >> non-interactive use cases. What would you think about adding something >> like ifup and ifdown commands so that users could explicitly start/stop >> interfaces? > > Sure, bringing I/F's up and down needlessly isn't a good thing. However my > patch doesn't change that behaviour. It only optimizes the need for a PHY AN > the first time one performs a eth transaction. >
I know. I guess my e-mail was more directed towards Detlev's musings. > Jocke Regards, Ben _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
