Re: [PATCH 7/9] fsl: add EPU FSM configuration for deep sleep

From: Chenhui Zhao
Date: Tue Mar 18 2014 - 20:09:38 EST


On Tue, Mar 18, 2014 at 06:21:22PM -0500, Scott Wood wrote:
> On Mon, 2014-03-17 at 18:27 +0800, Chenhui Zhao wrote:
> > On Fri, Mar 14, 2014 at 05:51:09PM -0500, Scott Wood wrote:
> > > On Wed, 2014-03-12 at 16:34 +0800, Chenhui Zhao wrote:
> > > > On Tue, Mar 11, 2014 at 07:08:43PM -0500, Scott Wood wrote:
> > > > > On Fri, 2014-03-07 at 12:58 +0800, Chenhui Zhao wrote:
> > > > > > + /* Configure the EPU Counters */
> > > > > > + epu_write(EPCCR15, 0x92840000);
> > > > > > + epu_write(EPCCR14, 0x92840000);
> > > > > > + epu_write(EPCCR12, 0x92840000);
> > > > > > + epu_write(EPCCR11, 0x92840000);
> > > > > > + epu_write(EPCCR10, 0x92840000);
> > > > > > + epu_write(EPCCR9, 0x92840000);
> > > > > > + epu_write(EPCCR8, 0x92840000);
> > > > > > + epu_write(EPCCR5, 0x92840000);
> > > > > > + epu_write(EPCCR4, 0x92840000);
> > > > > > + epu_write(EPCCR2, 0x92840000);
> > > > > > +
> > > > > > + /* Configure the SCUs Inputs */
> > > > > > + epu_write(EPSMCR15, 0x76000000);
> > > > > > + epu_write(EPSMCR14, 0x00000031);
> > > > > > + epu_write(EPSMCR13, 0x00003100);
> > > > > > + epu_write(EPSMCR12, 0x7F000000);
> > > > > > + epu_write(EPSMCR11, 0x31740000);
> > > > > > + epu_write(EPSMCR10, 0x65000030);
> > > > > > + epu_write(EPSMCR9, 0x00003000);
> > > > > > + epu_write(EPSMCR8, 0x64300000);
> > > > > > + epu_write(EPSMCR7, 0x30000000);
> > > > > > + epu_write(EPSMCR6, 0x7C000000);
> > > > > > + epu_write(EPSMCR5, 0x00002E00);
> > > > > > + epu_write(EPSMCR4, 0x002F0000);
> > > > > > + epu_write(EPSMCR3, 0x2F000000);
> > > > > > + epu_write(EPSMCR2, 0x6C700000);
> > > > >
> > > > > Where do these magic numbers come from? Which chips are they valid for?
> > > >
> > > > They are for T1040. Can be found in the RCPM chapter of T1040RM.
> > >
> > > Then put in a comment to that effect, including what part of the RCPM
> > > chapter.
> > >
> > > How do you plan to handle the addition of another SoC with different
> > > values?
> > >
> > > -Scott
> >
> > Had thought that using an array to put these values (pairs of offset and value)
> > and passing the array to the function.
>
> Arrays are better than a long sequence of function calls in any case.
>
> > However, luckily T104x and LS1 have same values for these registers
> > according to the current Reference Manuals.
>
> If it's likely that the values will remain the same on all chips for the
> near future, then a fancy mechanism to select the array to use can wait
> -- but you should still use an array, and have a comment acknowledging
> the possibility of needing to accommodate different values in the
> future.
>
> -Scott

OK. Will use an array to pass the values.

-Chenhui

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