Re: [PATCH] ARM: dts: imx6sl: correct PWM ipg clock source

From: Uwe Kleine-König
Date: Wed Dec 19 2018 - 03:52:09 EST


Hello,

On Wed, Dec 19, 2018 at 08:44:13AM +0000, Anson Huang wrote:
> i.MX6SL current setting has no issue, because the ipg_clk_s is from perclk which is always
> ON, but it does NOT match the clock info in reference manual, while other i.MX6 SoCs
> are having correct clock settings for PWM IPG clock.
>
> It is just an improvement, NOT fix a real problem.

OK, so it's merge window material as I expected.

> > > Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
> > > ---
> > > arch/arm/boot/dts/imx6sl.dtsi | 8 ++++----
> > > 1 file changed, 4 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/arch/arm/boot/dts/imx6sl.dtsi
> > > b/arch/arm/boot/dts/imx6sl.dtsi index e7524e7..4b4813f 100644
> > > --- a/arch/arm/boot/dts/imx6sl.dtsi
> > > +++ b/arch/arm/boot/dts/imx6sl.dtsi
> > > @@ -338,7 +338,7 @@
> > > compatible = "fsl,imx6sl-pwm", "fsl,imx27-pwm";
> > > reg = <0x02080000 0x4000>;
> > > interrupts = <0 83 IRQ_TYPE_LEVEL_HIGH>;
> > > - clocks = <&clks IMX6SL_CLK_PWM1>,
> > > + clocks = <&clks IMX6SL_CLK_PERCLK>,
> > > <&clks IMX6SL_CLK_PWM1>;
> > > clock-names = "ipg", "per";
> >
> > It's a bit irritating that IMX6SL_CLK_PERCLK is used for the "ipg" clk, not the
> > "per" clk. Is this correct?
>
> Yes, you can check the i.MX6SL CCM chapter for PWM clocks, the ipg_clk_s
> is from perclk and its enabled control is VCC which is always ON. The "per"
> clock is for PWM function, NOT register access, I tried disabling the PWM per clock,
> PWM registers still can be accessed.

OK, then Acked-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>

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haha, something between you and me mangles links. I bet it's on your
side.

Best regards
Uwe

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