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

Russell King - ARM Linux
2011-01-25T12:18:04Z

On Tue, Jan 25, 2011 at 05:38:49PM +0530, Santosh Shilimkar wrote:
> 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.

He was already added on my previous email... we're going round in circles.