> -----Original Message----- > From: Kevin Hilman [mailto:khil...@deeprootsystems.com] > Sent: Thursday, September 10, 2009 11:51 PM > To: Premi, Sanjeev > Cc: linux-omap@vger.kernel.org > Subject: Re: [PATCH 1/1] PM : cpuidle - update statistics for > correct state > > Sanjeev Premi <pr...@ti.com> writes: > > > When 'enable_off_mode' is 0, the target power state for MPU > > and Core is locally changed to PWRDM_POWER_RET but, the > > statistics are updated for idle state originally selected > > by the governor. > > > > This patch 'invalidates' the idle states that lead either of > > MPU or Core to PWRDM_POWER_OFF state when 'enable_off_mode' > > is '0'. The states are valid once 'enable_off_mode' is set > > to '1'. > > > > Signed-off-by: Sanjeev Premi <pr...@ti.com> > > This is a good start, but doesn't actually fix the problem. This is > because the 'valid' field is an OMAP specific field and is not checked > in any of our 'enter_idle' hooks. > > It works in your test case because the code snippet you mentioned in > PATCH 0/0 still modifies the target state. > > What we need is for the enter_idle_bm() enter function to check the > .valid flag. If it's not valid, then keep dropping states until it > finds a valid flag or it hits the safe state.
We do have a omap3_enter_idle_bm(), but the problem is that calculating the current index in dev->states will be costly operation. We know the pointer to 'target' c-state; but the translating the index back to the omap3_power_states[] seems 'intense' operation in idle_bm check. I believe the right solution will be to add .valid in the cpuidle framework itself. I am submitting a patch for same. Best regards, Sanjeev > > Kevin > > [snip]---[snip]---[snip]-- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
