[PATCHv2 7/8] arm: omap: clockdomain: add support for preventing domain transitions

Tero Kristo t-kristo at ti.com
Thu Feb 16 03:58:26 EST 2012


On Thu, 2012-02-16 at 14:13 +0530, Shilimkar, Santosh wrote:
> Tero,
> On Thu, Feb 16, 2012 at 2:09 PM, Tero Kristo <t-kristo at ti.com> wrote:
> > On Wed, 2012-02-15 at 11:35 -0800, Kevin Hilman wrote:
> >> Tero Kristo <t-kristo at ti.com> writes:
> >>
> >> > Some clockdomains can't support manual domain transitions triggered by
> >> > clock framework, and must be prevented from doing so. Added clkdm flag
> >> > CLKDM_NO_MANUAL_TRANS for doing this.
> >> >
> >> > Signed-off-by: Tero Kristo <t-kristo at ti.com>
> >> > Cc: Paul Walmsley <paul at pwsan.com>
> >> > Cc: Kevin Hilman <khilman at ti.com>
> >>
> >> Dumb Q: what's the difference between this new flag and CLKDM_CAN_SWSUP?
> >
> > CAN_SWSUP controls software wakeup / sleep (clktrctrl values 1 and 2),
> > but it still allows hwsup based transitions during runtime (basically
> > using values 0 & 3 for the same register.) NO_MANUAL_TRANS prevents
> > both, but still allows hwauto mode being enabled in the first place.
> >
> > I was thinking about adding a flag for preventing the autodep disabling
> > as this was the root cause for the problem I saw, but I wanted to
> > optimize the _clkdm_clk_hwmod_enable/disable for this case, as the
> > domain is not going through any transitions.
> >
> Which clock-domain you are refering here which needs this
> flag ?

per_clkdm, see patch 8 in this same set for comments. This happens with
omap3.

> 
> Regards
> santosh





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