Re: [Xenomai-help] How can I make Xenomai share a mii bus with the kernel?

[Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>]

Michael Galea wrote:
> I wonder if someone can suggest an approach to the following problem.
> 
> We need to use xenomai to manage devices on the mii bus.  The mii bus 
> has PHYs managed by linux. What is the best way of providing access to 
> both linux and xenomai?
> 
> I know that before xenomai "loads", I can simply access the mii bus from 
> linux.  But after xenomai loads, is the right answer to make the linux 
> function that reads the phy migrate into the xenomai domain and contend 
> for the bus there?

What protects this access to the bus, is this a mutex or a spinlock ? If 
a spinlock, then simply make it an ipipe_spinlock, it will provide 
mutual exclusion between all domains.

I do not think it can be a mutex anyway, since it may certainly possible 
for a driver to have a function that reads the mii status in a timer 
handler to maintain the IFF_RUNNING bit state of the ethernet interface.

-- 
                                                  Gilles.