[PATCH] clk: sunxi: Refactor A31 PLL6 so that it can be reused

Maxime Ripard maxime.ripard at free-electrons.com
Sun Nov 8 17:52:25 PST 2015


Hi Chen-Yu,

On Thu, Nov 05, 2015 at 10:28:00AM +0800, Chen-Yu Tsai wrote:
> On Wed, Nov 4, 2015 at 11:44 PM, Maxime Ripard
> <maxime.ripard at free-electrons.com> wrote:
> > Remove the fixed dividers from the PLL6 driver to be able to have a
> > reusable driver that can be used across several SoCs that share the same
> > controller, but don't have the same set of dividers for this clock, and to
> > also be reused multiple times in the same SoC, since we're droping the
> > clock name.
> >
> > Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
> > ---
> > Hi Jens,
> >
> > Here is an alternative (untested) patch to deal with the PLL6 issue you're
> > experiencing with the H3.
> >
> > It doesn't rely on parsing clock-output-names that turns out to be pretty
> > fragile.
> 
> A quick look through. I've no problems with changing the design, but I'd
> like to keep the original names, i.e. pll6x2 for the clock module bits,
> and pll6 for the fixed divider. It better matches the user manual.
> 
> From the PLL6 register description:
> In the Clock Control Module, PLL(2X) output = PLL * 2= 24 MHz * N * K.
> 
> And all places that use the "normal" output say PLL_PERIPH (that is PLL6),
> while MBUS on A23/A33 use the 2X output, and say PLL_PERIPH(2X).

Ack, I'll change this.

> On the side, do we want to get rid of all the divs clocks?

Eventually, yes. A10's PLL6 is pretty much in the same situation.

PLL5 is a different story though, since it has an extra adjustable
divider. It would probably deserve its own driver.

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
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