[PATCH v2 1/4] ARM: dts: sun8i: r40: add /omit-if-no-ref/ to pinmux nodes for UARTs 0&3

Andre Przywara andre.przywara at arm.com
Mon Mar 22 16:18:04 GMT 2021


On Mon, 22 Mar 2021 13:55:35 +0300
Ivan Uvarov <i.uvarov at cognitivepilot.com> wrote:

Hi,

> This patch adds the /omit-if-no-ref/ keyword to the pio nodes for
> UART0 and UART3 pins of the R40 SoC, which would reduce the fdt size on
> boards which do not use these UARTs.

But what boards are those? It seems like all boards use uart3-pg and
the two existing boards use UART0.

I think the idea is to use omit-if-no-ref on some rarely used nodes, so
if there is only a single user, for instance. Your next patch is a good
example.

So I don't think this patch here is needed at all.

Cheers,
Andre

> 
> Signed-off-by: Ivan Uvarov <i.uvarov at cognitivepilot.com>
> 
>  1 file changed, 3 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/sun8i-r40.dtsi b/arch/arm/boot/dts/sun8i-r40.dtsi
> index d5ad3b9efd..0b257a0779 100644
> --- a/arch/arm/boot/dts/sun8i-r40.dtsi
> +++ b/arch/arm/boot/dts/sun8i-r40.dtsi
> @@ -631,16 +631,19 @@ spi1_cs1_pi_pin: spi1-cs1-pi-pin {
>  				function = "spi1";
>  			};
>  
> +			/omit-if-no-ref/
>  			uart0_pb_pins: uart0-pb-pins {
>  				pins = "PB22", "PB23";
>  				function = "uart0";
>  			};
>  
> +			/omit-if-no-ref/
>  			uart3_pg_pins: uart3-pg-pins {
>  				pins = "PG6", "PG7";
>  				function = "uart3";
>  			};
>  
> +			/omit-if-no-ref/
>  			uart3_rts_cts_pg_pins: uart3-rts-cts-pg-pins {
>  				pins = "PG8", "PG9";
>  				function = "uart3";




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