Re: [PATCH V12 2/4] ptp: Added a clock that uses the eTSEC foundon the MPC85xx.

[Richard Cochran]

On Wed, Mar 23, 2011 at 02:30:04PM -0700, John Stultz wrote:
> On Mon, 2011-02-28 at 08:57 +0100, Richard Cochran wrote:
> > +/*
> > + * Register access functions
> > + */
> 
> So what are the locking rules on the functions below? I assume the
> etsects->lock needs to be held prior to calling, so that should be made
> explicit in a comment.

Yes, you are right. I'll add comments.

> > +	gfar_write(&etsects->regs->tmr_ctrl,   tmr_ctrl);
> > +	gfar_write(&etsects->regs->tmr_add,    etsects->tmr_add);
> > +	gfar_write(&etsects->regs->tmr_prsc,   etsects->tmr_prsc);
> > +	gfar_write(&etsects->regs->tmr_fiper1, etsects->tmr_fiper1);
> > +	gfar_write(&etsects->regs->tmr_fiper2, etsects->tmr_fiper2);
> > +	set_alarm(etsects);
> > +	gfar_write(&etsects->regs->tmr_ctrl,   tmr_ctrl|FS|RTPE|TE);
> 
> Does any of the above need a lock should an irq land in the middle of
> the writes?

Since these interrupts first must be enabled, I think it unlikely that
an IRQ could occur. However, it can't hurt to add the lock, either.

Thanks,

Richard
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