Re: [PATCH 2a/5 v2] ARM: OMAP1: select clock rate by CPU type

From: Tony Lindgren
Date: Thu Dec 01 2011 - 14:06:44 EST


* Janusz Krzysztofik <jkrzyszt@xxxxxxxxxxxx> [111201 10:19]:
> On Thursday 01 of December 2011 at 19:22:54, Tony Lindgren wrote:
> > * Janusz Krzysztofik <jkrzyszt@xxxxxxxxxxxx> [111201 01:35]:
> > > On Wednesday 30 of November 2011 at 23:28:38, Tony Lindgren wrote:
> > > >
> > > > We should also now be able to remove all the CONFIG_OMAP_ARM_XXXMHZ options
> > > > too, right?
> > >
> > > Right, but then, perhaps the initial version of patch 2a/5, which
> > > already started removing them, from omap1_defconfig for now, then going
> > > into the right direction while unblocking another regression fix (3/5),
> > > _is_ a good candidate for an rc fix?
> >
> > But we did not allow dpll1 reprogramming earlier either,
>
> Wrong. Without OMAP_CLOCKS_SET_BY_BOOTLOADER selected, we always did,
> but only once, early at boot, before ck_dpll1_p->rate was set first from
> omap1_clk_init(), and never retried later, that's why that check which I
> removed with 3/5 was never in the game until e9b7086b80c4d9e354f4edc9e280ae85a60df408.

Yeah you're right. You found what caused the regression :)

> > so we should
> > not need to make all these changes during the -rc cycle. I'm suspecting
> > that we've had this same behaviour for a really long time, and we just
> > have not seen it as omap1_defconfig had OMAP_CLOCKS_SET_BY_BOOTLOADER
> > option set.
> >
> > So I'm baffled how your board would be booting at a different rate
> > compared to v3.1, it seems that the logic has not changed there. Or
> > else we have some simple bug somewhere.
> >
> > Care to try to verify at what point your system started booting at
> > 60MHz rate?
>
> Since e9b7086b80c4d9e354f4edc9e280ae85a60df408, I guess, and it's hard
> to confirm wituout bisecting the issue with too early sram call, back
> until things still worked like before map_io related changes. I will do
> that if you decide we should try to revert.

No need to bisect, I think we can just reset ck_dpll1_p->rate for
systems booting at below 60MHz rate to force the reprogramming.

Regards,

Tony
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