[PATCH v2 3/3] riscv: dts: starfive: Enable PCIe host controller

[Pali Rohár]

On Wednesday 08 March 2023 13:48:33 Minda Chen wrote:
> From: Mason Huo <mason.huo at starfivetech.com>
> 
> Enable and add pinctrl configuration for PCIe host controller.
> Also add JH7110 stg syscon configuration.
> 
> Signed-off-by: Mason Huo <mason.huo at starfivetech.com>
> Signed-off-by: Minda Chen <minda.chen at starfivetech.com>
> ---
>  .../dts/jh7110-starfive-visionfive-2.dtsi     | 99 +++++++++++++++++++
>  arch/riscv/dts/jh7110.dtsi                    | 75 ++++++++++++++
>  2 files changed, 174 insertions(+)
> 
> diff --git a/arch/riscv/dts/jh7110-starfive-visionfive-2.dtsi b/arch/riscv/dts/jh7110-starfive-visionfive-2.dtsi
> index e669c2a26a..995f842a6b 100644
> --- a/arch/riscv/dts/jh7110-starfive-visionfive-2.dtsi
> +++ b/arch/riscv/dts/jh7110-starfive-visionfive-2.dtsi
> @@ -178,6 +178,87 @@
>  			slew-rate = <0>;
>  		};
>  	};
> +
> +	pcie0_perst_default: pcie0_perst_default {
> +		perst-pins {
> +			pinmux = <GPIOMUX(26, GPOUT_HIGH, GPOEN_ENABLE, GPI_NONE)>;
> +			drive-strength = <2>;
> +			input-disable;
> +			input-schmitt-disable;
> +			slew-rate = <0>;
> +		};
> +	};
> +
> +	pcie0_perst_active: pcie0_perst_active {
> +		perst-pins {
> +			pinmux = <GPIOMUX(26, GPOUT_LOW, GPOEN_ENABLE, GPI_NONE)>;
> +			drive-strength = <2>;
> +			input-disable;
> +			input-schmitt-disable;
> +			slew-rate = <0>;
> +		};
> +	};
...
> +&pcie0 {
> +	pinctrl-names = "perst-default", "perst-active", "wake-default", "clkreq-default";
> +	pinctrl-0 = <&pcie0_perst_default>;
> +	pinctrl-1 = <&pcie0_perst_active>;
> +	pinctrl-2 = <&pcie0_wake_default>;
> +	pinctrl-3 = <&pcie0_clkreq_default>;
> +	status = "disabled";
> +};

This is not correct declaration of PERST# signal. You should define in
&pcie0 node "reset-gpios" property with plain gpio definition with
active state.

"reset-gpios" is standard PCIe property for controlling PERST# signal
over GPIO. Look for example into drivers/pci/pci-aardvark.c and
arch/arm/dts/armada-3720-espressobin.dtsi files how it is used.