* Paul Walmsley <p...@pwsan.com> [110705 00:35]:
> Hi Tony
> 
> On Mon, 4 Jul 2011, Tony Lindgren wrote:
> 
> > * Paul Walmsley <p...@pwsan.com> [110702 21:09]:
> > 
> > > Here are some options that come to mind:
> > > 
> > > 1. Wait until the driver runtime PM conversion is finished before doing 
> > >    anything.  In the meantime, boards with IP blocks that can't be reset 
> > >    - N810, TI 4460 boards - will have problems.
> > > 
> > > 2. Merge the lazy/unused hwmod reset code, but prevent IP blocks 
> > >    controlled by non-runtime PM drivers from being reset.  We'd have to
> > >    maintain a list of these somewhere, perhaps in some common code called 
> > >    by board file init_machine code.  Then we'd need to redact that list 
> > > as 
> > >    new driver runtime PM conversions complete.
> > > 
> > > 3. Merge the lazy/unused hwmod reset code, but disable the unused hwmod 
> > >    reset code until the driver runtime PM conversion is finished.  This
> > >    could cause problems with driverless devices that are left configured
> > >    by bootloaders or ROM code, and that problem would reoccur for each new
> > >    OMAP chip.
> > > 
> > > Do you have a preference as to which approach to take?
> > 
> > I think #3 above is the safest option. How about make it only happen with
> > hwmod_reset=1 cmdline with 0 being the default value?
> 
> With the patch that was posted, that would disable all reset.  Probably we 
> want to reset devices that have drivers with PM runtime support?

Can't we always reset the registered hwmods automatically one at a time when
omap_device_build is called?

> That would allow drivers to assume that they are starting from consistent 
> device state.  It also should prevent some power management problems 
> that are dependent on particular bootloaders.   How about if we add a 
> second parameter, hwmod_reset_unused?  The default could be 'no' and then 
> only devices with PM runtime-enabled drivers would be reset first.

Yes I think hwmod_reset_unsed would be a better name, but do we actually
need any other reset option in addition to that?

TOny
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