From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: Phy read timeout in ibm_new_emac driver
Date: Wed, 23 Apr 2008 15:18:48 +1000
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On Wed, 2008-04-23 at 07:06 +0200, Markus Brunner wrote:
> On Wednesday 16 April 2008, Benjamin Herrenschmidt wrote:
> 
> > Somebody knows off hand what the standard says the timeout should be ?
> 
> Anyone?
> 
> I didn't find any documentation on the standard, but I had a look at other 
> drivers. 
> au1000_eth.c waits 20 ms (20 * 1ms) in mdio_read.
> bfin_mac.c waits 500 * 1us in mdio_poll. 
> In both functions the last delay before the timeout is useless, like in 
> new_emac. Not nice, but timeouts shouldn't occur anyway.
> 
> new emac probably doesn't wait long enough, but 20ms seems to be a bit too 
> long.

I just send Jeff a patch doubling the timeouts.

Cheers,
Ben.