Pasted

#include "am335x-boneblack.dts"
#include <dt-bindings/pinctrl/am33xx.h>
#include <dt-bindings/board/am335x-bbw-bbb-base.h>
 
&{/chosen} {
    base_dtb = "am335x-boneblack-custom-example.dts";   // <-- name of this file goes here
};
 
// if you want to use UIO-PRUSS:
#include "am335x-uio-pruss.dtsi"  // download from https://pastebin.com/yuFnTWWL
 
 
// if you want to disable HDMI:
&lcdc {  status = "disabled";  };
&tda19988 {  status = "disabled";  };
 
// if you want to disable HDMI or just disable HDMI audio:
/ {  /delete-node/ sound;  };
&mcasp0 {  status = "disabled";  };
 
 
// example to enable UART4:
&uart4 {
    status = "okay";
 
    pinctrl-names = "default";
    pinctrl-0 = <&uart4_pins>;
};
&am33xx_pinmux {
    // Note that a label ("uart4_pins") cannot contain punctuation other than underscores and must be globally unique.
    // On the other hand, for a node name ("uart4") it is conventional to use dashes as separators, not underscores, and
    // it only needs to be unique within the parent node, which in this case is the pinmux controller, so putting "pins"
    // or "pinmux" in the node name would be very redundant.
    //
    // My suggested naming scheme for pinmux nodes is:
    //    some_thing_pins: some-thing { ... };
    //
    uart4_pins: uart4 {
        pinctrl-single,pins = <
            BONE_P9_13 ( PIN_OUTPUT_PULLUP | MUX_MODE6 )  // txd
            BONE_P9_11 ( PIN_INPUT_PULLUP  | MUX_MODE6 )  // rxd
            // uncomment if you're using these:
        //  BONE_P8_33 ( PIN_OUTPUT_PULLUP | MUX_MODE6 )  // rts
        //  BONE_P8_35 ( PIN_INPUT_PULLUP  | MUX_MODE6 )  // cts
        >;
    };
};