Re: [PATCH E 08/14] OMAP clock: move rate recalc, propagation code up to plat-omap/clock.c

[Paul Walmsley <paul@pwsan.com>]

Hello Russell, 

On Sat, 31 Jan 2009, Russell King - ARM Linux wrote:

> On Fri, Jan 30, 2009 at 08:23:49AM -0600, Woodruff, Richard wrote:
> > 
> > > There's one bug that your version highlights in mine - the virtual mpu
> > > clock in omap1 touches the DPLL and repropagates that rate.  I've
> > > removed that repropagation, so that needs fixing.
> > >
> > > However, this raises a question: why is the virtual mpu clock touching
> > > some other part of the clock tree.  I wonder whether this should be
> > > handled a different way, though the first thing that needs answering is
> > > why we have this alias for 'arm_ck' ?
> > 
> > At one point in time the virtual clock allowed control for a set of clocks
> > with some dependencies.  The mpu alias provided a convenient control point.
> 
> >From what I can see (checking both mainline and Tony's tree), this mpu
> alias (virtual_ck_mpu) is not used on OMAP1, which seems to suggest
> that this quirk has become redundant.  If it is redundant, it should
> be removed.
>
> If there is some code somewhere to use it, this quirk should live with
> the user of the quirk until such time that the user becomes ready to be
> merged.

I don't think there's any reason for virtual_ck_mpu or virt_prcm_set to 
have a parent clock listed.  

At some point this year, those virtual OPP clocks will be removed from the 
clock tree and implemented in a different manner.

If you like, I will send a patch for removal of virtual_ck_mpu from OMAP1, 
although my suspicion is that OMAP1 is just missing a CPUFreq driver to 
use that OPP clock.


- Paul