Thread (4 messages) flat view 4 messages, 2 authors, 2004-08-08

Re: [2/3] via-rhine: de-isolate PHY

From: Manfred Spraul <hidden>
Date: 2004-08-08 21:01:37
Also in: lkml

Roger Luethi wrote:
 
quoted
I know that PHYs go into isolate mode if the startup id is wired to 0, 
   
Wouldn't that be s/go/can go/ ?

 
I don't have the MII standard, my knowledge is from the DP83840A specs:
The pin description contains a section about the phy ids:
During power up five pins are latched to determine the initial phy address.
Then the following sentence in bold: "An address selection of all zeros 
(00000) will result in a PHY isolation condition".

I've reread the DP specs and I now think that your current patch is 
sufficient:
The isolate state is independant from the phy address - a non-zero phy 
can be in isolate mode and the phy zero can be non-isolated. The phy id 
just sets the power-up value of the isolate bit: 0 means start isolated, 
non-zero means start non-isolated.

If this is really true then handling phy 0 is trivial:
First scan 1-31. If nothing found: try 0. If a phy is found: clear the 
isolate bit and then use phy 0.

--
    Manfred
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help