Re: [PATCH 3/6] ARM: mach-shmobile: extend clock definitions on

[Magnus Damm <magnus.damm@gmail.com>]

2010/7/6 Guennadi Liakhovetski <g.liakhovetski@gmx.de>:
> On Mon, 5 Jul 2010, Magnus Damm wrote:
>> On Fri, Jul 2, 2010 at 9:33 PM, Guennadi Liakhovetski
>> <g.liakhovetski@gmx.de> wrote:
>> > On Fri, 2 Jul 2010, Magnus Damm wrote:
>> >> On Wed, Jun 30, 2010 at 6:55 PM, Guennadi Liakhovetski
>> >> <g.liakhovetski@gmx.de> wrote:
>> >> > Add definitions for DV_CLKI and HDMI clocks, extend support for PLLC2 and some
>> >> > other clocks.
>> >> >
>> >> > Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>

>> >> > +       /*
>> >> > +        * TODO: If the PLL is off, mult should be = 1, but the clock must be
>> >> > +        * stopped during re-parenting, a better solution to this conflict
>> >> > +        * should be found.
>> >> > +        */
>> >> > +       mult = (((__raw_readl(PLLC2CR) >> 24) & 0x3f) + 1) * 2;
>> >>
>> >> Yes, this needs to be fixed.
>> >
>> > You mean now or in the future? If now - I don't see a reasonable fix so
>> > far... Do you?
>>
>> I'm not sure which way is the best, but I think this patch breaks the
>> case when the PLL is turned off.
>
> Ok, I can re-add the test and just add a line
>
> š š š š š š š šclk->rate = pllc2_recalc(clk);
>
> in pllc2_enable()? This even makes sense in a way - if we know, that
> after enabling the ->rate can get out of sync with the actual frequency...
> I'll prepare an updated patch to make it easier to see.

After looking into the pllc2 part of the data sheet it looks more like
it should be exported like a clock that cannot be disabled. So
basically, extend the frequency table to include one more frequency
and handle the pll-off case as a 1:1 mapping.

Cheers,

/ magnus