Re: [PATCH v4 2/2] arm64: dts: imx93-var-som: Add Variscite VAR-SOM-MX93

From: Mathieu Othacehe
Date: Fri Dec 29 2023 - 11:48:40 EST



Hey,

> I also saw in the other Symphony DTS a LED for heartbeat. Is it usable, too?

Yes, I will add it to in v5.

> According to the datasheet the SOM expose 7 UARTs, but only the debug
> UART is enable. What is the reason for this?

So those 7 UARTs are:

UART1: console
UART2: used by the microphone
UART3: used by the resistive touch
UART4: used by the ethernet/resistive touch
UART5: on J18.4,6,8,10 (used by BT)
UART6: on J18.7 and J18.9 (available)
UART7: on J18.3 and J18.5 (used by the M33 firmware)

I will enable UART6, and add a mention about UART7, something like:

/* J18.7, J18.9 */
&lpuart6 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_uart6>;
status = "okay";
};

/* J18.3, J18.5 - used by M33 firmware */
&lpuart7 {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_uart7>;
status = "disabled";
};

> Btw the commit log mentions a Wifi (via SDIO?) and audio interface. This
> is currently not supported by Linux?

I am not sure about that, and I would prefer to study that a bit later
on if that's OK :) I can remove it from the commit log as this is
misleading as not already supported / tested.

Thanks,

Mathieu