Re: [PATCH 05/15] arm64: dts: imx8mp-evk: enable uart1/3 ports
From: Marco Felsch
Date: Fri Oct 21 2022 - 05:10:33 EST
On 22-10-21, Peng Fan wrote:
> Hi Marco,
>
> On 10/20/2022 7:07 PM, Marco Felsch wrote:
> > Hi Peng,
> >
> > On 22-10-20, Peng Fan (OSS) wrote:
> > > From: Peng Fan <peng.fan@xxxxxxx>
> > >
> > > Enable uart1/3 ports for evk board.
> > >
> > > Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> > > ---
> > > arch/arm64/boot/dts/freescale/imx8mp-evk.dts | 36 ++++++++++++++++++++
> > > 1 file changed, 36 insertions(+)
> > >
> > > diff --git a/arch/arm64/boot/dts/freescale/imx8mp-evk.dts b/arch/arm64/boot/dts/freescale/imx8mp-evk.dts
> > > index 2e29bb3c041c..366f709f8790 100644
> > > --- a/arch/arm64/boot/dts/freescale/imx8mp-evk.dts
> > > +++ b/arch/arm64/boot/dts/freescale/imx8mp-evk.dts
> > > @@ -428,6 +428,15 @@ &snvs_pwrkey {
> > > status = "okay";
> > > };
> > > +&uart1 { /* BT */
> > > + pinctrl-names = "default";
> > > + pinctrl-0 = <&pinctrl_uart1>;
> > > + assigned-clocks = <&clk IMX8MP_CLK_UART1>;
> > > + assigned-clock-parents = <&clk IMX8MP_SYS_PLL1_80M>;
> >
> > I'm curious, what is the default parent and why is this wrong? For the
> > already exisiting uart2 we don't do that. Same applies for uart3.
>
> The default parent is OSC_24M. The uart2 is for console, so 24M is ok.
> As I recall, we met issue 24M not able to get higher baudrate.
What did you mean by higher baudrate, is it everything > 115200? When
the console baudrates can be fullfilled with the PLL1_80M as well
wouldn't it be worth to fix the imx8mp.dtsi instead?
Regards,
Marco