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From: "Dale Farnsworth" <dale@farnsworth.org>
Date: Fri, 9 Sep 2005 13:49:55 -0700
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Subject: Re: Marvell MV64360 interrupt question
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On Fri, Sep 09, 2005 at 08:20:20PM +0000, Walter L. Wimer III wrote:
> On Fri, 2005-09-09 at 12:27 -0700, Dale Farnsworth wrote:
> > 
> > No additional locking is necessary.  In fact, it seems to me that the 32-bit
> > register reads and writes are already atomic and all of the locking using
> > mv64x60_lock is superfluous.
> 
> Ah ha.  mv64x60.h also defines an mv64x60_modify() function that isn't
> intrinsically atomic, so it needs the spinlock.  That in turn requires
> mv64x60_read() and mv64x60_write() to play along too.

Yes, the lock is needed for mv64x60_modify(), mv64x60_write().  I still
don't think it's needed for mv64x60_read().

-Dale