Re: [PATCH v4 3/3] riscv: dts: spacemit: add pinctrl property to uart0 in BPI-F3

[Yixun Lan <dlan@gentoo.org>]

Hi Jesse

On 10:45 Sun 15 Sep     , Jesse Taube wrote:
> 
> Before pinctrl driver implemented, the uart0 controller reply on
> bootloader for setting correct pin mux and configurations.
> 
> Now, let's add pinctrl property to uart0 of Bananapi-F3 board.
> 
> Signed-off-by: Yixun Lan <dlan@gentoo.org>
> ---
>   arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts |  3 +++
>   arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi    | 20 ++++++++++++++++++++
>   arch/riscv/boot/dts/spacemit/k1.dtsi            |  5 +++++
>   3 files changed, 28 insertions(+)
> 
> diff --git a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts 
> b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
> index 023274189b492..bc88d4de25a62 100644
> --- a/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
> +++ b/arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts
> @@ -4,6 +4,7 @@
>    */
> 
>   #include "k1.dtsi"
> +#include "k1-pinctrl.dtsi"
> 
>   / {
>   	model = "Banana Pi BPI-F3";
> @@ -15,5 +16,7 @@ chosen {
>   };
> 
>   &uart0 {
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&uart0_2_cfg>;
>   	status = "okay";
>   };
> diff --git a/arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi 
> b/arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi
> new file mode 100644
> index 0000000000000..a8eac5517f857
> --- /dev/null
> +++ b/arch/riscv/boot/dts/spacemit/k1-pinctrl.dtsi
> @@ -0,0 +1,20 @@
> +// SPDX-License-Identifier: GPL-2.0 OR MIT
> +/*
> + * Copyright (c) 2024 Yixun Lan <dlan@gentoo.org>
> + */
> +
> +#include <dt-bindings/gpio/gpio.h>
> +
> +#define K1_PADCONF(pin, func) (((pin) << 16) | (func))
> 
> It would be nice to have a pinfunc header like
> arch/arm/boot/dts/nxp/imx/imx7ulp-pinfunc.h.
> It would reference and encode the data of "3.2 Pin Multiplex" in
> https://developer.spacemit.com/documentation?token=An1vwTwKaigaXRkYfwmcznTXned 
> , the document you attached in the summary.
Not sure if it's worth the effort..

I gave up of introducing another macro, as it's exactly one to one mapping to
GPIO ID, which mean pin(x) -> GPIO_x

maybe I could put a comment at K1_PADCONF() to document this?

/* pin is same to the GPIO id according to 3.2 Pin Multiplex of User Manual */
#define K1_PADCONF(pin, func) (((pin) << 16) | (func))

does this sound good to you?

> 
> Otherwise,
> Acked-by: Jesse Taube <Mr.Bossman075@gmail.com>
> 
thanks

> +
> +&pinctrl {
> +	uart0_2_cfg: uart0-2-cfg {
> +		uart0-2-pins {
> +			pinmux = <K1_PADCONF(68, 2)>,
> +				 <K1_PADCONF(69, 2)>;
> +
> +			bias-pull-up = <0>;
> +			drive-strength = <32>;
> +		};
> +	};
> +};
> diff --git a/arch/riscv/boot/dts/spacemit/k1.dtsi 
> b/arch/riscv/boot/dts/spacemit/k1.dtsi
> index 0777bf9e01183..a2d5f7d4a942a 100644
> --- a/arch/riscv/boot/dts/spacemit/k1.dtsi
> +++ b/arch/riscv/boot/dts/spacemit/k1.dtsi
> @@ -416,6 +416,11 @@ uart9: serial@d4017800 {
>   			status = "disabled";
>   		};
> 
> +		pinctrl: pinctrl@d401e000 {
> +			compatible = "spacemit,k1-pinctrl";
> +			reg = <0x0 0xd401e000 0x0 0x400>;
> +		};
> +
>   		plic: interrupt-controller@e0000000 {
>   			compatible = "spacemit,k1-plic", "sifive,plic-1.0.0";
>   			reg = <0x0 0xe0000000 0x0 0x4000000>;
> 
> -- 
> 2.45.2

-- 
Yixun Lan (dlan)
Gentoo Linux Developer
GPG Key ID AABEFD55