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Date: Wed, 6 Jul 2011 15:01:49 -0600 (MDT)
From: Paul Walmsley <paul@pwsan.com>
To: Tony Lindgren <tony@atomide.com>
cc: linux-omap@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        Aaro Koskinen <aaro.koskinen@nokia.com>,
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        =?ISO-8859-15?Q?Beno=EEt_Cousson?= <b-cousson@ti.com>,
        Michael Buesch <mb@bu3sch.de>
Subject: Re: [PATCH] OMAP: hwmod: add kernel cmdline flag to avoid resetting
 IP blocks during init
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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