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Subject: Re: [2/4] powerpc/rcpm: add RCPM driver
From: Scott Wood <scottwood@freescale.com>
To: Zhao Chenhui-B35336 <chenhui.zhao@freescale.com>
Date: Thu, 2 Apr 2015 10:50:50 -0500
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On Thu, 2015-04-02 at 05:33 -0500, Zhao Chenhui-B35336 wrote:
> > +static int rcpm_v2_plat_enter_state(int state)
> > +{
> > +     u32 *pmcsr_reg = &rcpm_v2_regs->powmgtcsr;
> > +     int ret = 0;
> > +     int result;
> > +
> > +     switch (state) {
> > +     case PLAT_PM_LPM20:
> > +             /* clear previous LPM20 status */
> > +             setbits32(pmcsr_reg, RCPM_POWMGTCSR_P_LPM20_ST);
> 
> How would the bit be set when you enter here, given that you wait for it
> to clear when leaving?
> 
> [chenhui] Actually, the bit is not used by software. Just follow the instruction in RM.

Sorry, I missed the "_P_" and thought it was RCPM_POWMGTCSR_LPM20_ST.

-Scott