imx8mm M4 vs Linux gpio interrupt flag clear

[matt67]

Hello,

We are using the imx8mm evaluation board with Linux 4.14 and a DTS based on the evk-m4 (with more disabled things), which is the following:

  /*
   * Copyright 2018 NXP
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License
   * as published by the Free Software Foundation; either version 2
   * of the License, or (at your option) any later version.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   */

  /dts-v1/;

  #include "fsl-imx8mm.dtsi"

  / {
   model = "FSL i.MX8MM EVK board";
   compatible = "fsl,imx8mm-evk", "fsl,imx8mm";

   chosen {
    bootargs = "console=ttymxc1,115200 earlycon=ec_imx6q,0x30890000,115200";
    stdout-path = &uart2;
   };
   

   reserved-memory {
    #address-cells = <2>;
    #size-cells = <2>;
    ranges;

    m4_reserved: m4@0x80000000 {
     no-map;
     reg = <0 0x80000000 0 0x1000000>;
    };

   };
   
   regulators {
    compatible = "simple-bus";
    #address-cells = <1>;
    #size-cells = <0>;

    reg_sd1_vmmc: sd1_regulator {
     compatible = "regulator-fixed";
     regulator-name = "WLAN_EN";
     regulator-min-microvolt = <3300000>;
     regulator-max-microvolt = <3300000>;
     gpio = <&gpio2 10 GPIO_ACTIVE_HIGH>;
     off-on-delay = <20000>;
     startup-delay-us = <100>;
     enable-active-high;
    };

    reg_usdhc2_vmmc: regulator-usdhc2 {
     compatible = "regulator-fixed";
     regulator-name = "VSD_3V3";
     regulator-min-microvolt = <3300000>;
     regulator-max-microvolt = <3300000>;
     gpio = <&gpio2 19 GPIO_ACTIVE_HIGH>;
     off-on-delay = <20000>;
     enable-active-high;
    };
   };
  };

  &clk {
   assigned-clocks = <&clk IMX8MM_AUDIO_PLL1>, <&clk IMX8MM_AUDIO_PLL2>;
   assigned-clock-rates = <786432000>, <722534400>;
  };

  &iomuxc {
   pinctrl-names = "default";

   imx8mm-evk {

    pinctrl_fec1: fec1grp {
     fsl,pins = <
      MX8MM_IOMUXC_ENET_MDC_ENET1_MDC  0x3
      MX8MM_IOMUXC_ENET_MDIO_ENET1_MDIO 0x3
      MX8MM_IOMUXC_ENET_TD3_ENET1_RGMII_TD3 0x1f
      MX8MM_IOMUXC_ENET_TD2_ENET1_RGMII_TD2 0x1f
      MX8MM_IOMUXC_ENET_TD1_ENET1_RGMII_TD1 0x1f
      MX8MM_IOMUXC_ENET_TD0_ENET1_RGMII_TD0 0x1f
      MX8MM_IOMUXC_ENET_RD3_ENET1_RGMII_RD3 0x91
      MX8MM_IOMUXC_ENET_RD2_ENET1_RGMII_RD2 0x91
      MX8MM_IOMUXC_ENET_RD1_ENET1_RGMII_RD1 0x91
      MX8MM_IOMUXC_ENET_RD0_ENET1_RGMII_RD0 0x91
      MX8MM_IOMUXC_ENET_TXC_ENET1_RGMII_TXC 0x1f
      MX8MM_IOMUXC_ENET_RXC_ENET1_RGMII_RXC 0x91
      MX8MM_IOMUXC_ENET_RX_CTL_ENET1_RGMII_RX_CTL 0x91
      MX8MM_IOMUXC_ENET_TX_CTL_ENET1_RGMII_TX_CTL 0x1f
      MX8MM_IOMUXC_SAI2_RXC_GPIO4_IO22 0x19
     >;
    };

    pinctrl_flexspi0: flexspi0grp {
     fsl,pins = <
      MX8MM_IOMUXC_NAND_ALE_QSPI_A_SCLK  0x1c2
      MX8MM_IOMUXC_NAND_CE0_B_QSPI_A_SS0_B  0x82
      MX8MM_IOMUXC_NAND_DATA00_QSPI_A_DATA0  0x82
      MX8MM_IOMUXC_NAND_DATA01_QSPI_A_DATA1  0x82
      MX8MM_IOMUXC_NAND_DATA02_QSPI_A_DATA2  0x82
      MX8MM_IOMUXC_NAND_DATA03_QSPI_A_DATA3  0x82
     >;
    };

    pinctrl_i2c1: i2c1grp {
     fsl,pins = <
      MX8MM_IOMUXC_I2C1_SCL_I2C1_SCL   0x400001c3
      MX8MM_IOMUXC_I2C1_SDA_I2C1_SDA   0x400001c3
     >;
    };

    pinctrl_i2c2: i2c2grp {
     fsl,pins = <
      MX8MM_IOMUXC_I2C2_SCL_I2C2_SCL   0x400001c3
      MX8MM_IOMUXC_I2C2_SDA_I2C2_SDA   0x400001c3
     >;
    };

    pinctrl_pmic: pmicirq {
     fsl,pins = <
      MX8MM_IOMUXC_GPIO1_IO03_GPIO1_IO3  0x41
     >;
    };

    pinctrl_typec1: typec1grp {
     fsl,pins = <
      MX8MM_IOMUXC_SD1_STROBE_GPIO2_IO11 0x159
     >;
    };

    pinctrl_typec2: typec2grp {
     fsl,pins = <
      MX8MM_IOMUXC_SD2_CD_B_GPIO2_IO12 0x159
     >;
    };

    pinctrl_uart2: uart2grp {
     fsl,pins = <
      MX8MM_IOMUXC_UART2_RXD_UART2_DCE_RX 0x140
      MX8MM_IOMUXC_UART2_TXD_UART2_DCE_TX 0x140
     >;
    };

    pinctrl_usdhc1_gpio: usdhc1grpgpio {
     fsl,pins = <
      MX8MM_IOMUXC_SD1_RESET_B_GPIO2_IO10 0x41
     >;
    };

    pinctrl_usdhc1: usdhc1grp {
     fsl,pins = <
      MX8MM_IOMUXC_SD1_CLK_USDHC1_CLK  0x190
      MX8MM_IOMUXC_SD1_CMD_USDHC1_CMD  0x1d0
      MX8MM_IOMUXC_SD1_DATA0_USDHC1_DATA0 0x1d0
      MX8MM_IOMUXC_SD1_DATA1_USDHC1_DATA1 0x1d0
      MX8MM_IOMUXC_SD1_DATA2_USDHC1_DATA2 0x1d0
      MX8MM_IOMUXC_SD1_DATA3_USDHC1_DATA3 0x1d0
     >;
    };

    pinctrl_usdhc1_100mhz: usdhc1grp100mhz {
     fsl,pins = <
      MX8MM_IOMUXC_SD1_CLK_USDHC1_CLK  0x194
      MX8MM_IOMUXC_SD1_CMD_USDHC1_CMD  0x1d4
      MX8MM_IOMUXC_SD1_DATA0_USDHC1_DATA0 0x1d4
      MX8MM_IOMUXC_SD1_DATA1_USDHC1_DATA1 0x1d4
      MX8MM_IOMUXC_SD1_DATA2_USDHC1_DATA2 0x1d4
      MX8MM_IOMUXC_SD1_DATA3_USDHC1_DATA3 0x1d4
     >;
    };

    pinctrl_usdhc1_200mhz: usdhc1grp200mhz {
     fsl,pins = <
      MX8MM_IOMUXC_SD1_CLK_USDHC1_CLK  0x196
      MX8MM_IOMUXC_SD1_CMD_USDHC1_CMD  0x1d6
      MX8MM_IOMUXC_SD1_DATA0_USDHC1_DATA0 0x1d6
      MX8MM_IOMUXC_SD1_DATA1_USDHC1_DATA1 0x1d6
      MX8MM_IOMUXC_SD1_DATA2_USDHC1_DATA2 0x1d6
      MX8MM_IOMUXC_SD1_DATA3_USDHC1_DATA3 0x1d6
     >;
    };

    pinctrl_usdhc2_gpio: usdhc2grpgpio {
     fsl,pins = <
      MX8MM_IOMUXC_GPIO1_IO15_GPIO1_IO15 0x1c4
      MX8MM_IOMUXC_SD2_RESET_B_GPIO2_IO19 0x41
     >;
    };

    pinctrl_usdhc2: usdhc2grp {
     fsl,pins = <
      MX8MM_IOMUXC_SD2_CLK_USDHC2_CLK  0x190
      MX8MM_IOMUXC_SD2_CMD_USDHC2_CMD  0x1d0
      MX8MM_IOMUXC_SD2_DATA0_USDHC2_DATA0 0x1d0
      MX8MM_IOMUXC_SD2_DATA1_USDHC2_DATA1 0x1d0
      MX8MM_IOMUXC_SD2_DATA2_USDHC2_DATA2 0x1d0
      MX8MM_IOMUXC_SD2_DATA3_USDHC2_DATA3 0x1d0
      MX8MM_IOMUXC_GPIO1_IO04_USDHC2_VSELECT 0x1d0
     >;
    };

    pinctrl_usdhc2_100mhz: usdhc2grp100mhz {
     fsl,pins = <
      MX8MM_IOMUXC_SD2_CLK_USDHC2_CLK  0x194
      MX8MM_IOMUXC_SD2_CMD_USDHC2_CMD  0x1d4
      MX8MM_IOMUXC_SD2_DATA0_USDHC2_DATA0 0x1d4
      MX8MM_IOMUXC_SD2_DATA1_USDHC2_DATA1 0x1d4
      MX8MM_IOMUXC_SD2_DATA2_USDHC2_DATA2 0x1d4
      MX8MM_IOMUXC_SD2_DATA3_USDHC2_DATA3 0x1d4
      MX8MM_IOMUXC_GPIO1_IO04_USDHC2_VSELECT 0x1d0
     >;
    };

    pinctrl_usdhc2_200mhz: usdhc2grp200mhz {
     fsl,pins = <
      MX8MM_IOMUXC_SD2_CLK_USDHC2_CLK  0x196
      MX8MM_IOMUXC_SD2_CMD_USDHC2_CMD  0x1d6
      MX8MM_IOMUXC_SD2_DATA0_USDHC2_DATA0 0x1d6
      MX8MM_IOMUXC_SD2_DATA1_USDHC2_DATA1 0x1d6
      MX8MM_IOMUXC_SD2_DATA2_USDHC2_DATA2 0x1d6
      MX8MM_IOMUXC_SD2_DATA3_USDHC2_DATA3 0x1d6
      MX8MM_IOMUXC_GPIO1_IO04_USDHC2_VSELECT 0x1d0
     >;
    };

    pinctrl_usdhc3: usdhc3grp {
     fsl,pins = <
      MX8MM_IOMUXC_NAND_WE_B_USDHC3_CLK  0x190
      MX8MM_IOMUXC_NAND_WP_B_USDHC3_CMD  0x1d0
      MX8MM_IOMUXC_NAND_DATA04_USDHC3_DATA0  0x1d0
      MX8MM_IOMUXC_NAND_DATA05_USDHC3_DATA1  0x1d0
      MX8MM_IOMUXC_NAND_DATA06_USDHC3_DATA2  0x1d0
      MX8MM_IOMUXC_NAND_DATA07_USDHC3_DATA3  0x1d0
      MX8MM_IOMUXC_NAND_RE_B_USDHC3_DATA4  0x1d0
      MX8MM_IOMUXC_NAND_CE2_B_USDHC3_DATA5  0x1d0
      MX8MM_IOMUXC_NAND_CE3_B_USDHC3_DATA6  0x1d0
      MX8MM_IOMUXC_NAND_CLE_USDHC3_DATA7  0x1d0
      MX8MM_IOMUXC_NAND_CE1_B_USDHC3_STROBE   0x190
     >;
    };

    pinctrl_usdhc3_100mhz: usdhc3grp100mhz {
     fsl,pins = <
      MX8MM_IOMUXC_NAND_WE_B_USDHC3_CLK  0x194
      MX8MM_IOMUXC_NAND_WP_B_USDHC3_CMD  0x1d4
      MX8MM_IOMUXC_NAND_DATA04_USDHC3_DATA0  0x1d4
      MX8MM_IOMUXC_NAND_DATA05_USDHC3_DATA1  0x1d4
      MX8MM_IOMUXC_NAND_DATA06_USDHC3_DATA2  0x1d4
      MX8MM_IOMUXC_NAND_DATA07_USDHC3_DATA3  0x1d4
      MX8MM_IOMUXC_NAND_RE_B_USDHC3_DATA4  0x1d4
      MX8MM_IOMUXC_NAND_CE2_B_USDHC3_DATA5  0x1d4
      MX8MM_IOMUXC_NAND_CE3_B_USDHC3_DATA6  0x1d4
      MX8MM_IOMUXC_NAND_CLE_USDHC3_DATA7  0x1d4
      MX8MM_IOMUXC_NAND_CE1_B_USDHC3_STROBE   0x194
     >;
    };

    pinctrl_usdhc3_200mhz: usdhc3grp200mhz {
     fsl,pins = <
      MX8MM_IOMUXC_NAND_WE_B_USDHC3_CLK  0x196
      MX8MM_IOMUXC_NAND_WP_B_USDHC3_CMD  0x1d6
      MX8MM_IOMUXC_NAND_DATA04_USDHC3_DATA0  0x1d6
      MX8MM_IOMUXC_NAND_DATA05_USDHC3_DATA1  0x1d6
      MX8MM_IOMUXC_NAND_DATA06_USDHC3_DATA2  0x1d6
      MX8MM_IOMUXC_NAND_DATA07_USDHC3_DATA3  0x1d6
      MX8MM_IOMUXC_NAND_RE_B_USDHC3_DATA4  0x1d6
      MX8MM_IOMUXC_NAND_CE2_B_USDHC3_DATA5  0x1d6
      MX8MM_IOMUXC_NAND_CE3_B_USDHC3_DATA6  0x1d6
      MX8MM_IOMUXC_NAND_CLE_USDHC3_DATA7  0x1d6
      MX8MM_IOMUXC_NAND_CE1_B_USDHC3_STROBE   0x196
     >;
    };

    pinctrl_wdog: wdoggrp {
     fsl,pins = <
      MX8MM_IOMUXC_GPIO1_IO02_WDOG1_WDOG_B  0xc6
     >;
    };
   };
  };


  &flexspi {
   pinctrl-names = "default";
   pinctrl-0 = <&pinctrl_flexspi0>;
   status = "okay";

   flash0: mt25qu256aba@0 {
    reg = <0>;
    #address-cells = <1>;
    #size-cells = <1>;
    compatible = "micron,mt25qu256aba";
    spi-max-frequency = <29000000>;
    spi-nor,ddr-quad-read-dummy = <6>;
   };
  };

  &i2c1 {
   clock-frequency = <400000>;
   pinctrl-names = "default";
   pinctrl-0 = <&pinctrl_i2c1>;
   status = "okay";

   pmic: bd71837@4b {
    reg = <0x4b>;
    compatible = "rohm,bd71840", "rohm,bd71837";
    /* PMIC BD71837 PMIC_nINT GPIO1_IO3 */
    pinctrl-0 = <&pinctrl_pmic>;
    gpio_intr = <&gpio1 3 GPIO_ACTIVE_LOW>;

    gpo {
     rohm,drv = <0x0C>; /* 0b0000_1100 all gpos with cmos output mode */
    };

    regulators {
     #address-cells = <1>;
     #size-cells = <0>;

     bd71837,pmic-buck2-uses-i2c-dvs;
     bd71837,pmic-buck2-dvs-voltage = <1000000>, <900000>, <0>; /* VDD_ARM: Run-Idle */

     buck1_reg: regulator@0 {
      reg = <0>;
      regulator-compatible = "buck1";
      regulator-min-microvolt = <700000>;
      regulator-max-microvolt = <1300000>;
      regulator-boot-on;
      regulator-always-on;
      regulator-ramp-delay = <1250>;
     };

     buck2_reg: regulator@1 {
      reg = <1>;
      regulator-compatible = "buck2";
      regulator-min-microvolt = <700000>;
      regulator-max-microvolt = <1300000>;
      regulator-boot-on;
      regulator-always-on;
      regulator-ramp-delay = <1250>;
     };

     buck3_reg: regulator@2 {
      reg = <2>;
      regulator-compatible = "buck3";
      regulator-min-microvolt = <700000>;
      regulator-max-microvolt = <1300000>;
     };

     buck4_reg: regulator@3 {
      reg = <3>;
      regulator-compatible = "buck4";
      regulator-min-microvolt = <700000>;
      regulator-max-microvolt = <1300000>;
     };

     buck5_reg: regulator@4 {
      reg = <4>;
      regulator-compatible = "buck5";
      regulator-min-microvolt = <700000>;
      regulator-max-microvolt = <1350000>;
      regulator-boot-on;
      regulator-always-on;
     };

     buck6_reg: regulator@5 {
      reg = <5>;
      regulator-compatible = "buck6";
      regulator-min-microvolt = <3000000>;
      regulator-max-microvolt = <3300000>;
      regulator-boot-on;
      regulator-always-on;
     };

     buck7_reg: regulator@6 {
      reg = <6>;
      regulator-compatible = "buck7";
      regulator-min-microvolt = <1605000>;
      regulator-max-microvolt = <1995000>;
      regulator-boot-on;
      regulator-always-on;
     };

     buck8_reg: regulator@7 {
      reg = <7>;
      regulator-compatible = "buck8";
      regulator-min-microvolt = <800000>;
      regulator-max-microvolt = <1400000>;
      regulator-boot-on;
      regulator-always-on;
     };

     ldo1_reg: regulator@8 {
      reg = <8>;
      regulator-compatible = "ldo1";
      regulator-min-microvolt = <3000000>;
      regulator-max-microvolt = <3300000>;
      regulator-boot-on;
      regulator-always-on;
     };

     ldo2_reg: regulator@9 {
      reg = <9>;
      regulator-compatible = "ldo2";
      regulator-min-microvolt = <900000>;
      regulator-max-microvolt = <900000>;
      regulator-boot-on;
      regulator-always-on;
     };

     ldo3_reg: regulator@10 {
      reg = <10>;
      regulator-compatible = "ldo3";
      regulator-min-microvolt = <1800000>;
      regulator-max-microvolt = <3300000>;
      regulator-boot-on;
      regulator-always-on;
     };

     ldo4_reg: regulator@11 {
      reg = <11>;
      regulator-compatible = "ldo4";
      regulator-min-microvolt = <900000>;
      regulator-max-microvolt = <1800000>;
      regulator-boot-on;
      regulator-always-on;
     };

     ldo6_reg: regulator@13 {
      reg = <13>;
      regulator-compatible = "ldo6";
      regulator-min-microvolt = <900000>;
      regulator-max-microvolt = <1800000>;
      regulator-boot-on;
      regulator-always-on;
     };
    };
   };
  };

  &i2c2 {
   clock-frequency = <400000>;
   pinctrl-names = "default";
   pinctrl-0 = <&pinctrl_i2c2>;
   status = "okay";

   adv_bridge: adv7535@3d {
    compatible = "adi,adv7533";
    reg = <0x3d>;
    adi,addr-cec = <0x3b>;
    adi,dsi-lanes = <4>;
    status = "okay";

    port {
     adv7535_from_dsim: endpoint {
      remote-endpoint = <&dsim_to_adv7535>;
     };
    };
   };

   typec1_ptn5110: tcpci@50 {
    compatible = "usb,tcpci";
    pinctrl-names = "default";
    pinctrl-0 = <&pinctrl_typec1>;
    reg = <0x50>;
    interrupt-parent = <&gpio2>;
    interrupts = <11 8>;
    src-pdos = <0x380190c8>;
    snk-pdos = <0x380190c8>;
    /* Only can sink 5V for safe */
    max-snk-mv = <5000>;
    max-snk-ma = <3000>;
    op-snk-mw = <10000>;
    max-snk-mw = <15000>;
    port-type = "drp";
    default-role = "sink";
    status = "okay";
   };

   typec2_ptn5110: tcpci@52 {
    compatible = "usb,tcpci";
    pinctrl-names = "default";
    pinctrl-0 = <&pinctrl_typec2>;
    reg = <0x52>;
    interrupt-parent = <&gpio2>;
    interrupts = <12 8>;
    src-pdos = <0x380190c8>;
    snk-pdos = <0x380190c8>;
    /* Only can sink 5V for safe */
    max-snk-mv = <5000>;
    max-snk-ma = <3000>;
    op-snk-mw = <10000>;
    max-snk-mw = <15000>;
    port-type = "drp";
    default-role = "sink";
    status = "okay";
   };
  };


  &mipi_csi_1 {
   #address-cells = <1>;
   #size-cells = <0>;
   status = "disabled";
  };


  &lcdif {
   status = "disabled";
  };

  &mipi_dsi {
   status = "disabled";

   port@1 {
    dsim_to_adv7535: endpoint {
     remote-endpoint = <&adv7535_from_dsim>;
    };
   };
  };

  &mu {
   status = "okay";
  };

  &rpmsg{
   /*
    * 64K for one rpmsg instance:
    * --0xb8000000~0xb800ffff: pingpong
    */
   vdev-nums = <1>;
   reg = <0x0 0xb8000000 0x0 0x10000>;
   status = "okay";
  };

  &fec1 {
   pinctrl-names = "default";
   pinctrl-0 = <&pinctrl_fec1>;
   phy-mode = "rgmii-id";
   phy-handle = <&ethphy0>;
   fsl,magic-packet;
   status = "okay";

   mdio {
    #address-cells = <1>;
    #size-cells = <0>;

    ethphy0: ethernet-phy@0 {
     compatible = "ethernet-phy-ieee802.3-c22";
     reg = <0>;
     at803x,led-act-blind-workaround;
     at803x,eee-okay;
     at803x,vddio-1p8v;
    };
   };
  };

  &pcie0{
   status = "disabled";
  };


  &uart2 { /* console */
   pinctrl-names = "default";
   pinctrl-0 = <&pinctrl_uart2>;
   status = "okay";
  };

  &uart3 {
   status = "disabled";
  };

  &usbotg1 {
   dr_mode = "otg";
   extcon = <0>, <&typec1_ptn5110>;
   picophy,pre-emp-curr-control = <3>;
   picophy,dc-vol-level-adjust = <7>;
   status = "okay";
  };

  &usbotg2 {
   dr_mode = "otg";
   extcon = <0>, <&typec2_ptn5110>;
   picophy,pre-emp-curr-control = <3>;
   picophy,dc-vol-level-adjust = <7>;
   status = "disabled";
  };

  &usdhc1 {
   pinctrl-names = "default", "state_100mhz", "state_200mhz";
   pinctrl-0 = <&pinctrl_usdhc1>, <&pinctrl_usdhc1_gpio>;
   pinctrl-1 = <&pinctrl_usdhc1_100mhz>, <&pinctrl_usdhc1_gpio>;
   pinctrl-2 = <&pinctrl_usdhc1_200mhz>, <&pinctrl_usdhc1_gpio>;
   bus-width = <4>;
   vmmc-supply = <&reg_sd1_vmmc>;
   pm-ignore-notify;
   keep-power-in-suspend;
   non-removable;
   status = "okay";
  };

  &usdhc2 {
   pinctrl-names = "default", "state_100mhz", "state_200mhz";
   pinctrl-0 = <&pinctrl_usdhc2>, <&pinctrl_usdhc2_gpio>;
   pinctrl-1 = <&pinctrl_usdhc2_100mhz>, <&pinctrl_usdhc2_gpio>;
   pinctrl-2 = <&pinctrl_usdhc2_200mhz>, <&pinctrl_usdhc2_gpio>;
   cd-gpios = <&gpio1 15 GPIO_ACTIVE_LOW>;
   bus-width = <4>;
   vmmc-supply = <&reg_usdhc2_vmmc>;
   status = "okay";
  };

  &usdhc3 {
   pinctrl-names = "default", "state_100mhz", "state_200mhz";
   pinctrl-0 = <&pinctrl_usdhc3>;
   pinctrl-1 = <&pinctrl_usdhc3_100mhz>;
   pinctrl-2 = <&pinctrl_usdhc3_200mhz>;
   bus-width = <8>;
   non-removable;
   status = "okay";
  };

  &wdog1 {
   pinctrl-names = "default";
   pinctrl-0 = <&pinctrl_wdog>;
   fsl,ext-reset-output;
   status = "okay";
  };

  &A53_0 {
   arm-supply = <&buck2_reg>;
  };

  &gpu {
   status = "okay";
  };

  &vpu_g1 {
   status = "okay";
  };

  &vpu_g2 {
   status = "okay";
  };

  &vpu_h1 {
   status = "okay";
  };

  &sdma1{
  status = "disabled";
  };

  &uart4 {
  status = "disabled";
  };

  &sdma3 {
  status = "disabled";
  };

  &sai1 {
  status = "disabled";
  };

  &flexspi {
  status = "disabled";
  };



‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

On the M4 side, we run a firmware that handles some GPIOs routed from the expansion header.

One is the GPIO3 IO22, from the pad SAI5_RXD1, configured in input with interruption.

The problem, is that in the handler the flag (GPIO3_ISR) is automatically cleared if Linux is running, and leads to a Linux hang if we clear it in the same time.

/* GPIO3 IRQ Handler */
void GPIO3_Combined_16_31_IRQHandler(void)
{

    if ((BOARD_GPIO_3->IMR | BOARD_GPIO_3_S2LP_IRQ_CONFIG_MASK) != 0)
    {
        // Tmp remove code for debugging...
    }

    // Clear flag
    GPIO_ClearPinsInterruptFlags(BOARD_GPIO_3, BOARD_GPIO_3_S2LP_IRQ_CONFIG_MASK);
}
‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

On the device tree, there is absolutely no mention to any GPIO3, so I can't understand why is Linux clearing the flag.

Any idea ? 

[matt67 · Accepted solution]

Hello,

Thanks for reply.

Solution was found, in fact the GPIO3 is declared in fsl-imx8mm.dtsi  :

 gpio3: gpio@30220000 {
  compatible = "fsl,imx8mm-gpio", "fsl,imx35-gpio";
  reg = <0x0 0x30220000 0x0 0x10000>;
  interrupts = <GIC_SPI 68 IRQ_TYPE_LEVEL_HIGH>,
        <GIC_SPI 69 IRQ_TYPE_LEVEL_HIGH>;
  gpio-controller;
  #gpio-cells = <2>;
  interrupt-controller;
  #interrupt-cells = <2>;
 };‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

This result in loading the gpio3 device in the driver gpio-mxs.c and the IRQ handler is clearing the flag when interrupt occurs on any GPIO of this bank :

/* MXS has one interrupt *per* gpio port */
static void mxs_gpio_irq_handler(struct irq_desc *desc)
{
 u32 irq_stat;
 struct mxs_gpio_port *port = irq_desc_get_handler_data(desc);

 desc->irq_data.chip->irq_ack(&desc->irq_data);

 irq_stat = readl(port->base + PINCTRL_IRQSTAT(port)) &
   readl(port->base + PINCTRL_IRQEN(port));

 while (irq_stat != 0) {
  int irqoffset = fls(irq_stat) - 1;
  if (port->both_edges & (1 << irqoffset))
   mxs_flip_edge(port, irqoffset);

  generic_handle_irq(irq_find_mapping(port->domain, irqoffset));
  irq_stat &= ~(1 << irqoffset);
 }
}‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

If this occurs in the same time on the Cortex-M4 firmware side, Linux hangs.

The solution is then to disable the whole GPIO3 in our board device tree :

 &gpio3 {
 status = "disabled";
 };‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

To prevent such things, we are protecting all the imx8 M4 peripherals with the Rdc domain assignments.

Example of the Rdc can be found on MCUExpresso "rdc.zip".

[igorpadykov]

Hi matt67

gpio3_16 is used as led in

fsl-imx8mm-evk.dts\freescale\dts\boot\arm64\arch - linux-imx - i.MX Linux kernel 

pad SAI5_RXD1 can be used as PDM_DATA1.

Also may be useful to rebuild all image from scratch.

Best regards
igor
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