Re: [RFC/PATCH] Fixes for ULi5261 (tulip driver)

[Pozsar Balazs <pozsy@uhulinux.hu>]

On Tue, Aug 22, 2006 at 11:28:21PM -0700, Valerie Henson wrote:
> Hi Pozsar,
> 
> On Mon, Aug 21, 2006 at 11:03:51AM +0200, Pozsar Balazs wrote:
> > 
> > Does this seem better?
> > 
> > Signed-off-by: Pozsar Balazs <pozsy@uhulinux.hu>
> > 
> > Fix uli526x initialization
> > 
> > 
> > --- a/drivers/net/tulip/uli526x.c	2006-08-21 10:57:43.000000000 +0200
> > +++ a/drivers/net/tulip/uli526x.c	2006-08-21 11:01:37.000000000 +0200
> > @@ -486,6 +486,7 @@
> >  	u8	phy_tmp;
> >  	u16	phy_value;
> >  	u16 phy_reg_reset;
> > +	int resetwait = 10;
> >  
> >  	ULI526X_DBUG(0, "uli526x_init()", 0);
> >  
> > @@ -515,7 +516,11 @@
> >  	phy_reg_reset = phy_read(db->ioaddr, db->phy_addr, 0, db->chip_id);
> >  	phy_reg_reset = (phy_reg_reset | 0x8000);
> >  	phy_write(db->ioaddr, db->phy_addr, 0, phy_reg_reset, db->chip_id);
> > -	udelay(500);
> > +	while (resetwait-- > 0) {
> > +		if (!(phy_read(db->ioaddr, db->phy_addr, 0, db->chip_id) & 0x8000))
> > +			break;
> > +		udelay(500);
> > +	}
> >  
> >  	/* Process Phyxcer Media Mode */
> >  	uli526x_set_phyxcer(db);
> 
> Thanks for writing up this patch.  udelay(500) seems a touch
> heavyweight, however.

I don't really understand, 500 microsec is really not that much time...


> Would you mind experimenting a bit to see what
> the delay typically ends up being?  Just add a KERN_DEBUG message
> printing out resetwait and then fiddle with the udelay granularity.

The funny thing is that it seems the _first_ phy_read call always 
returns only when the 0x8000 bit is gone (I got this while loop from the 
xircom_tulip driver).
I didn't have time yet to test how long it takes without the phy_read to 
make it work (ie if we would only raise udelay(500) to some bigger 
value).


-- 
pozsy
-
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