Re: [PATCH] OMAP: hwmod: add kernel cmdline flag to avoid resetting IP blocks during init

Paul Walmsley
2011-07-06T21:01:52Z

On Tue, 5 Jul 2011, Tony Lindgren wrote:

> * Paul Walmsley <paul@pwsan.com> [110705 18:55]:
> > On Tue, 5 Jul 2011, Paul Walmsley wrote:
> >
> > > For this case, we probably need some board file function to tell the
> > > hwmod code to disregard a device completely, to tell the kernel to
> > > pretend that the device does not exist.
> >
> > ... and the other problem here is that we currently probe devices via an
> > arch_initcall(), and the board file init_machine is also an arch_initcall.
> > Either we'll need to be very careful about Makefile ordering, or we should
> > just call omap2_init_devices() from the board file init_machine directly.
> > The latter makes the most sense to me.
>
> And that can then be passed the list of devices with the special flags
> for noreset, disabled and reserved. Then the late_initcall can optionally
> reset the rest of the devices.

'disabled' can probably be the default for a device that doesn't have a
driver associated with it, once the runtime PM conversion is complete.
That's what the late_initcall would do. Then if a driver is dynamically
loaded for one of those devices, the hwmod code would just re-enable it.

- Paul