RE: [PATCH 3/5] ARM: twd: Add context save restore support

Santosh Shilimkar
2011-01-25T12:08:52Z

Looping Thomas G
> -----Original Message-----
> From: Russell King - ARM Linux [mailto:linux@arm.linux.org.uk]
> Sent: Tuesday, January 25, 2011 5:19 PM
> To: Santosh Shilimkar
> Cc: Colin Cross; catalin.marinas@arm.com;
> linus.ml.walleij@gmail.com; linux-omap@vger.kernel.org; linux-arm-
> kernel@lists.infradead.org
> Subject: Re: [PATCH 3/5] ARM: twd: Add context save restore support
>
> On Tue, Jan 25, 2011 at 05:10:37PM +0530, Santosh Shilimkar wrote:
> > As I was suspecting the one shot mode wouldn't work it. Collin
> > just confirmed it.
> > To make it fully work it needs control register save restore.
> > And that can be managed within TWD library so that every platform
> > doesn't have to bother of calling it from their idle code.
> >
> > Do you prefer that as a separate patch or I can post a new version
> > in which can add your fix + per cpu control register shadowing ?
>
> I said earlier:
> | The next question is can we teach the generic time infrastructure
> about
> | this so we don't have to modify every clock event driver for it?
> We
> | really need to get away from having this kind of knowledge buried
> down
> | in the lowest levels of every driver.
>
> IOW, if we go into a PM idle mode, when we come back out we need to
> call clockevent set_mode to ensure that the control register is
> properly
> reset. I don't think its right to have this kind of knowledge
> buried
> in each and every clockevent driver.
May be Thomas can comment on this.

Regards,
Santosh