Add the PCIe support on iMX8MM EVK boards.
And set the default reference clock mode.

Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
Tested-by: Marcel Ziswiler <redacted>
---
 arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi | 55 +++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi b/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
index e033d0257b5a..fc1803a8af5b 100644
--- a/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mm-evk.dtsi

@@ -5,6 +5,7 @@

 
 /dts-v1/;
 
+#include <dt-bindings/phy/phy-imx8-pcie.h>
 #include <dt-bindings/usb/pd.h>
 #include "imx8mm.dtsi"
 

@@ -30,6 +31,23 @@ status {

                };
        };
 
+       pcie0_refclk: pcie0-refclk {
+               compatible = "fixed-clock";
+                       #clock-cells = <0>;
+                       clock-frequency = <100000000>;
+       };
+
+       reg_pcie0: regulator-pcie {
+               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";

@@ -289,6 +307,30 @@ pca6416: gpio@20 {

        };
 };
 
+&pcie_phy {
+       fsl,refclk-pad-mode = <IMX8_PCIE_REFCLK_PAD_INPUT>;
+       fsl,tx-deemph-gen1 = <0x2D>;
+       fsl,tx-deemph-gen2 = <0xF>;

+       clocks = <&pcie0_refclk>;
+       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>,
+                <&pcie0_refclk>;
+       clock-names = "pcie", "pcie_aux", "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>;
+       status = "okay";
+};
+
 &sai3 {
        pinctrl-names = "default";
        pinctrl-0 = <&pinctrl_sai3>;

@@ -406,6 +448,19 @@ 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