[PATCH 4/6] OMAP3: cpuidle: next C-state decision depends on the PM QoS MPU and CORE constraints

Kevin Hilman khilman at ti.com
Tue Dec 13 18:49:00 EST 2011


jean.pihet at newoldbits.com writes:

> From: Jean Pihet <j-pihet at ti.com>
>
> The MPU latency figures for cpuidle include the MPU itself and also
> the peripherals needed for the MPU to execute instructions (e.g.
> main memory, caches, IRQ controller, MMU etc). On OMAP3 those
> peripherals belong to the MPU and CORE power domains and so the
> cpuidle C-states are a combination of MPU and CORE states.
>
> This patch implements the relation between the cpuidle and per-
> device PM QoS frameworks in the OMAP3 specific idle callbacks.
>
> The chosen C-state shall satisfy the following conditions:
>  . the 'valid' field is enabled,
>  . it satisfies the enable_off_mode flag,
>  . the next state for MPU and CORE power domains is not lower than the
>    next state calculated by the per-device PM QoS.
>
> Tested on OMAP3 Beagleboard in RET/OFF using wake-up latency constraints
> on MPU, CORE and PER.
>
> Signed-off-by: Jean Pihet <j-pihet at ti.com>

nit: this patch mixes functional changes and non-functional changes
(whitespace cleanups, alignments etc.)  For ease of review, it's best to
do non-functional cleanups as a separate patch.

Kevin




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