Re: [PATCH] arm64: dts: imx8mp: use correct clock for eqos timestamping counter

[Fabio Estevam]

Hi Johannes,

On Wed, Jul 19, 2023 at 10:59 AM Johannes Zink <j.zink@xxxxxxxxxxxxxx> wrote:
>
> The i.MX8MP Reference Manual rev 1 06/2021, section 11.7.2.5 "Timestamp
> Support" indicates the PTP timestamp clock expects a typical frequency
> of 125MHz.
>
> As this also improves the precision of the measured timestamps: assign
> appropriate 125MHz Clock parent. As no one except the timestamping
> counter uses this clock, there are no side-effects of this change in
> other peripherals.
>
> Signed-off-by: Johannes Zink <j.zink@xxxxxxxxxxxxxx>
> ---
>  arch/arm64/boot/dts/freescale/imx8mp.dtsi | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm64/boot/dts/freescale/imx8mp.dtsi b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> index 6f2f50e1639c..7f80dff914c2 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx8mp.dtsi
> @@ -1334,7 +1334,7 @@ eqos: ethernet@30bf0000 {
>                                                   <&clk IMX8MP_CLK_ENET_QOS_TIMER>,
>                                                   <&clk IMX8MP_CLK_ENET_QOS>;
>                                 assigned-clock-parents = <&clk IMX8MP_SYS_PLL1_266M>,
> -                                                        <&clk IMX8MP_SYS_PLL2_100M>,
> +                                                        <&clk IMX8MP_SYS_PLL2_125M>,
>                                                          <&clk IMX8MP_SYS_PLL2_125M>;
>                                 assigned-clock-rates = <0>, <100000000>, <125000000>;

Shouldn't this also be changed to:

assigned-clock-rates = <0>, <125000000>, <125000000>;