[PATCH] ARM: OMAP2+: timer: remove CONFIG_OMAP_32K_TIMER

Hiremath, Vaibhav hvaibhav at ti.com
Mon Nov 12 05:38:07 EST 2012


On Fri, Nov 09, 2012 at 00:46:28, Hunter, Jon wrote:
> 
> On 11/08/2012 12:59 PM, Hiremath, Vaibhav wrote:
> > On Fri, Nov 09, 2012 at 00:24:23, Hunter, Jon wrote:
> >>
> >> On 11/08/2012 01:59 AM, Igor Grinberg wrote:
> >>
> >> [snip]
> >>
> >>> There is no reliable way to determine which source should be used in runtime
> >>> for boards that do not have the 32k oscillator wired.
> >>
> >> So thinking about this some more and given that we are moving away from
> >> board files, if a board does not provide a 32kHz clock source, then this
> >> should be reflected in the device-tree source file for that board.
> >> Hence, at boot time we should be able to determine if a 32kHz clock
> >> source can be used.
> >>
> > 
> > Let me feed some more thoughts here :)
> > 
> > The way it is being detected currently is based on timer idle status bit.
> > I am worried that, this is the only option we have.
> 
> Why not use device-tree to indicate the presence of a 32k clock source?
> This seems like a board level configuration and so device-tree seems to
> be the perfect place for this IMO.
> 

I think I agree with you, but for this to happen in clean way, its time to 
start populating clock-nodes in DT, don't you think? Something like,


clocks {
	rtc_clk: clk at X {
		compatible = "crystal-32k, per-32k, xyz";
		clock-frequency = <32768>;
	};
	...
};

Timer {

	ref-clock = <&rtc_clk>;
};

What do you think?

Thanks,
Vaibhav



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