Re: [PATCH v3 8/9] arm64: dts: imx8mm-evk: add the pcie support on imx8mm evk board

[Lucas Stach <l.stach@pengutronix.de>]

Am Dienstag, dem 12.10.2021 um 16:41 +0800 schrieb Richard Zhu:
> Add the PCIe support on i.MX8MM EVK board.
> 
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> ---
>  arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi | 46 +++++++++++++++++++
>  1 file changed, 46 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi b/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
> index 2d0684ac82f6..5ce43daa0c8b 100644
> --- a/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
> +++ b/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
> @@ -31,6 +31,23 @@ status {
>  		};
>  	};
>  
> +	pcie0_refclk: pcie0-refclk {
> +		compatible = "fixed-clock";
> +			#clock-cells = <0>;
> +			clock-frequency = <100000000>;
> +	};

This is both the PHY reference and bus clock. I guess you could just
squash Patch 4/9 into this one, as they are both required to get PCIe
on the EVK board.

> +
> +	reg_pcie0_gpio: regulator-pcie-gpio {

Drop the gpio suffix.

> +		compatible = "regulator-fixed";
> +		pinctrl-names = "default";
> +		pinctrl-0 = <&pinctrl_pcie0_reg>;
> +		regulator-name = "MPCIE_3V3";
> +		regulator-min-microvolt = <3300000>;
> +		regulator-max-microvolt = <3300000>;
> +		gpio = <&gpio1 5 GPIO_ACTIVE_HIGH>;
> +		enable-active-high;
> +	};
> +
>  	reg_usdhc2_vmmc: regulator-usdhc2 {
>  		compatible = "regulator-fixed";
>  		pinctrl-names = "default";
> @@ -296,6 +313,22 @@ &pcie_phy {
>  	status = "okay";
>  };
>  
> +&pcie0 {
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&pinctrl_pcie0>;
> +	reset-gpio = <&gpio4 21 GPIO_ACTIVE_LOW>;
> +	clocks = <&clk IMX8MM_CLK_PCIE1_ROOT>, <&clk IMX8MM_CLK_PCIE1_AUX>,
> +		 <&clk IMX8MM_CLK_DUMMY>, <&pcie0_refclk>;

The i.MX8MM PCIe driver should not request the pcie_phy clock. Please
add a change in the driver, so we don't need to hook up a useless dummy
clock to this node.

Regards,
Lucas

> +	clock-names = "pcie", "pcie_aux", "pcie_phy", "pcie_bus";
> +	assigned-clocks = <&clk IMX8MM_CLK_PCIE1_AUX>,
> +			  <&clk IMX8MM_CLK_PCIE1_CTRL>;
> +	assigned-clock-rates = <10000000>, <250000000>;
> +	assigned-clock-parents = <&clk IMX8MM_SYS_PLL2_50M>,
> +				 <&clk IMX8MM_SYS_PLL2_250M>;
> +	vpcie-supply = <&reg_pcie0_gpio>;
> +	status = "okay";
> +};
> +
>  &sai3 {
>  	pinctrl-names = "default";
>  	pinctrl-0 = <&pinctrl_sai3>;
> @@ -413,6 +446,19 @@ MX8MM_IOMUXC_I2C3_SDA_I2C3_SDA			0x400001c3
>  		>;
>  	};
>  
> +	pinctrl_pcie0: pcie0grp {
> +		fsl,pins = <
> +			MX8MM_IOMUXC_I2C4_SCL_PCIE1_CLKREQ_B    0x61
> +			MX8MM_IOMUXC_SAI2_RXFS_GPIO4_IO21       0x41
> +		>;
> +	};
> +
> +	pinctrl_pcie0_reg: pcie0reggrp {
> +		fsl,pins = <
> +			MX8MM_IOMUXC_GPIO1_IO05_GPIO1_IO5       0x41
> +		>;
> +	};
> +
>  	pinctrl_pmic: pmicirqgrp {
>  		fsl,pins = <
>  			MX8MM_IOMUXC_GPIO1_IO03_GPIO1_IO3		0x141