设备树 ranges 属性 更全讲解

    smb: smb@4000000 {
        compatible = "simple-bus";

        #address-cells = <2>;
        #size-cells = <1>;
        ranges = <0 0 0x40000000 0x04000000>,
             <1 0 0x44000000 0x04000000>,
             <2 0 0x48000000 0x04000000>,
             <3 0 0x4c000000 0x04000000>,
             <7 0 0x10000000 0x00020000>;

    smb@4000000 {
        motherboard {
            model = "V2M-P1";
            arm,hbi = <0x190>;
            arm,vexpress,site = <0>;
            compatible = "arm,vexpress,v2m-p1", "simple-bus";
            #address-cells = <2>; /* SMB chipselect number and offset */
            #size-cells = <1>;
            #interrupt-cells = <1>;
            ranges;

            flash@0,00000000 {
                compatible = "arm,vexpress-flash", "cfi-flash";
                reg = <0 0x00000000 0x04000000>,
                      <1 0x00000000 0x04000000>;
                bank-width = <4>;
                partitions {
                    compatible = "arm,arm-firmware-suite";
                };
            };