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From: "Walter L. Wimer III" <walt.wimer@timesys.com>
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Date: Fri, 09 Sep 2005 16:20:20 -0400
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Subject: Re: Marvell MV64360 interrupt question
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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.

At least in the general case....



Walt