[QUESTION] How to set static/dynamic dependency between clock domains
tom.leiming at gmail.com
Fri Dec 16 10:46:20 EST 2011
On Fri, Dec 16, 2011 at 11:13 PM, Shilimkar, Santosh
<santosh.shilimkar at ti.com> wrote:
> On Fri, Dec 16, 2011 at 7:20 PM, Ming Lei <tom.leiming at gmail.com> wrote:
>> On Fri, Dec 16, 2011 at 9:24 PM, Ming Lei <tom.leiming at gmail.com> wrote:
>>> , add static dependency
>> Sorry for the mess, see attachment for the change.
> Your patch is setting static dependency between ISS and l3_2.
> It's not dynamic dep. Dynamic dep is managed through hardware and they
Yes, I see now, L3_2_DYNDEP of CM_CAM_DYNAMICDEP is read only.
> are not configurable. But with static dep. you can over-ride that behavior
> as you have done.
> This will impact power since l3_2 can't idle as long as iss clock
> domain is active.
> I need to check internal code-base but I don't remember this
> issue observed so far.
In fact, I saw the issue on 3.2.0-rc5-next-20111216, and even
no such issue on 3.2.0-rc5. After some bisecting, I found below
is the first commit on which the issue can be observed:
Author: Santosh Shilimkar <santosh.shilimkar at ti.com>
Date: Wed Jan 5 22:03:17 2011 +0530
ARM: OMAP4: PM: Initialise all the clockdomains to supported states
Initialise hardware supervised mode for all clockdomains if it's
supported. Initiate sleep transition for other clockdomains,
if they are not being used.
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