[PATCH 1/2] OMAP3: cpuidle: prevent CORE power domain from going to RET or OFF when DSS is on

[Kevin Hilman]

<Tero.Kristo at nokia.com> writes:

[...]

>>>>>
>>>>> +	/* If DSS is active, prevent CORE RET/OFF */
>>>>> +	dss_state = pwrdm_read_pwrst(dss_pd);
>>>>> +	if (dss_state == PWRDM_POWER_ON &&
>>>>> +	    core_next_state != PWRDM_POWER_ON)
>>>>> +		core_next_state = PWRDM_POWER_INACTIVE;
>>>>> +
>>>>
>>>>Due to sleepdeps/autodeps, when this code runs, DSS powerdomain is
>>>>always on.  The result is that CORE is always set to INACTIVE.
>>>
>>> Now I recall that someone was asking about a patch similar to this
>>> earlier, and had the same issue with DSS sleepdep collision.
>>
>>>
>>> What is the reason for having the sleepdep for DSS powerdomain anyway?
>>> At least I can't see any reason why the sleepdep for DSS should be
>>> set. In my opinion it should be perfectly okay for DSS domain to idle
>>> independently of MPU/CORE, as this is going to be better for power
>>> consumption also.
>>
>>Agreed, but currently the sleepdeps with MPU are automatically managed
>>(by clkdm autodeps and hwmod initiator deps.)  Until we have merged a
>>solution to more selectively enable sleepdeps (or remove them) $SUBJECT
>>patch cannot be merged.
>
> Ok I thought this is the case... it would be possible to implement a
> temporary/permanent solution that uses idle status check instead of
> pwrdm state check, and prevent core idle if dss is not going to
> idle. What is the current status with those idlest patches anyway?

Paul will have to answer that one.

Kevin