[PATCH 2/2] OMAP3: beagle xm: enable upto 800MHz OPP

Premi, Sanjeev premi at ti.com
Thu Jan 6 08:58:59 EST 2011

> -----Original Message-----
> From: linux-omap-owner at vger.kernel.org 
> [mailto:linux-omap-owner at vger.kernel.org] On Behalf Of Menon, Nishanth
> Sent: Thursday, January 06, 2011 7:15 PM
> To: Koen Kooi
> Cc: Hilman, Kevin; l-o; l-a; Tony
> Subject: Re: [PATCH 2/2] OMAP3: beagle xm: enable upto 800MHz OPP
> Koen Kooi had written, on 01/06/2011 07:00 AM, the following:
> > Op 6 jan 2011, om 13:24 heeft Nishanth Menon het volgende 
> geschreven:
> > 
> >> Kevin Hilman wrote, on 01/05/2011 05:28 PM:
> >>> Nishanth Menon<nm at ti.com>  writes:
> >>>
> >>>> Beagle XM uses 3730 and the board design allows enabling 
> 800MHz and 1GHz
> >>>> OPPs. However, We need Smart reflex class 1.5 and ABB to 
> enable 1GHz safely.
> >>>> For the moment, we tweak the default table to allow for 
> 800Mhz OPP usage.
> >>> Isn't this common to any board using 3730 (or 3630?)
> >> no it is not. only certain boards are capable of higher 
> frequencies - there is a procedure called PDN analysis and 
> vmin search that needs to be performed to guarentee this.
> > 
> > What about the "new" 3530s that can run at 720MHz? Those 
> have been speed binned and given a different SKU. I'm using 
> the attached 4 patches (Tony master + beagle patches _+ dvfs: 
> http://dominion.thruhere.net/git/cgit.cgi/linux-omap/log/?h=ko
> en/beagle-next) on my beagle C4 and overo tide to get 720MHz. 
> They don't really work:
> for 3530, keep in mind that not *all* boards can support 
> 720MHz (esp the 
> old 3430 boards, like my poor SDP3430).
> since we consider 3530 as 3430 as well, add a default disabled 720MHz 
> OPP in the 3430 table and enable it:
> a) if this has anything to do with board behavior (which, 
> unlike 36xx, I 
> dont think is the case for 35xx), enable similar to this patch on the 
> required boards on a need basis (e.g. based on board rev)
> b) if this is a silicon behavior, then, you should modify the 
> omap3_opp_init to ensure that for the right silicon this is enabled 
> (e.g. only for 3530 rev X onwards or something similar) - but 
> you will 
> need some way to detect it in s/w (not through bootargs please!)


Some of the patches generic that Koen attached are based on my
submissions. As part of migration to 2.6.37, I am in process of
validating them on internal integration tree. Will post them
soon... may be end of tomorrow.

I will be testing them on OMAP3EVM.



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