liminix/devices/gl-mt300a/default.nix

# GL.iNet GL-MT300A

rec {
  system = {
    crossSystem = {
      config = "mipsel-unknown-linux-musl";
      gcc = {
        abi = "32";
        arch = "mips32";          # maybe mips_24kc-
      };
    };
  };

  description = ''
    GL.iNet GL-MT300A
    ********************

    The GL-MT300A is based on a MT7620 chipset.

    The GL.iNet pocket router range makes nice cheap hardware for
    playing with Liminix or similar projects. The manufacturers seem
    open to the DIY market, and the devices have a reasonable amount
    of RAM and are much easier to get serial connections than many
    COTS routers.

    Wire up the serial connection: this probably involves opening
    the box, locating the serial header pins (TX, RX and GND) and
    connecting a USB TTL converter - e.g. a PL2303 based device - to
    it. The defunct OpenWRT wiki has a guide with some pictures. (If
    you don't have a USB TTL converter to hand, other options are
    available. For example, use the GPIO pins on a Raspberry Pi.)

    Run a terminal emulator such as Minicom on whatever is on the
    other end of the link. I use 115200 8N1 and find it also helps
    to set "Line tx delay" to 1ms, "backspace sends DEL" and
    "lineWrap on".

    When you turn the router on you should be greeted with some
    messages from U-Boot and a little bit of ASCII art, followed by
    the instruction to hit SPACE to stop autoboot. Do this and you
    will get a gl-mt300a> prompt.

    For flashing from uboot, the firmware partition is from
    0xbc050000 to 0xbcfd0000.

    WiFi on this device is provided by the rt2800soc module. It
    expects firmware to be present in the "factory" MTD partition, so
    - assuming we want to use the wireless - we need to build MTD
    support into the kernel even if we're using TFTP root.


    Vendor web page: https://www.gl-inet.com/products/gl-mt300a/

    OpenWrt web page: https://openwrt.org/toh/gl.inet/gl-mt300a

  '';
  installer = "flashimage";

  module = { pkgs, config, lib, ...}:
    let
      inherit (pkgs.liminix.networking) interface;
      inherit (pkgs) openwrt;
      mac80211 = pkgs.mac80211.override {
        drivers = ["rt2800soc"];
        klibBuild = config.system.outputs.kernel.modulesupport;
      };
    in {
      imports = [ ../../modules/arch/mipsel.nix ];
      hardware = {
        defaultOutput = installer;
        loadAddress = "0x80000000";
        entryPoint  = "0x80000000";

        # Creating 5 MTD partitions on "spi0.0":
        # 0x000000000000-0x000000030000 : "u-boot"
        # 0x000000030000-0x000000040000 : "u-boot-env"
        # 0x000000040000-0x000000050000 : "factory"
        # 0x000000050000-0x000000fd0000 : "firmware"
        # 2 uimage-fw partitions found on MTD device firmware
        # Creating 2 MTD partitions on "firmware":
        # 0x000000000000-0x000000260000 : "kernel"
        # 0x000000260000-0x000000f80000 : "rootfs"

        flash = {
          address = "0xbc050000";
          size ="0xf80000";
          eraseBlockSize = "65536";
        };
        rootDevice = "/dev/mtdblock5";

        dts = {
          src = "${openwrt.src}/target/linux/ramips/dts/mt7620a_glinet_gl-mt300a.dts";
          includes = [
            "${openwrt.src}/target/linux/ramips/dts"
          ];
        };
        networkInterfaces =
          let
            inherit (config.system.service.network) link;
            inherit (config.system.service) vlan;
            inherit (pkgs.liminix.services) oneshot;
            swconfig = oneshot {
              name = "swconfig";
              up = ''
                PATH=${pkgs.swconfig}/bin:$PATH
                swconfig dev switch0 set reset
                swconfig dev switch0 set enable_vlan 1
                swconfig dev switch0 vlan 1 set ports '1 2 3 4 6t'
                swconfig dev switch0 vlan 2 set ports '0 6t'
                swconfig dev switch0 set apply
              '';
              down = "${pkgs.swconfig}/bin/swconfig dev switch0 set reset";
            };
          in rec {
            eth = link.build { ifname = "eth0"; };
            # lan and wan ports are both behind a switch on eth0
            lan = vlan.build {
              ifname = "eth0.1";
              primary = eth;
              vid = "1";
              dependencies =  [swconfig eth];
            };
            wan = vlan.build {
              ifname = "eth0.2";
              primary = eth;
              vid = "2";
              dependencies =  [swconfig eth];
            };
            wlan = link.build {
              ifname = "wlan0";
              dependencies = [ mac80211 ];
            };
          };
      };
      boot.tftp = {
        loadAddress = "0x00A00000";
      };

      kernel = {
        src = pkgs.fetchurl {
          name = "linux.tar.gz";
          url = "https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.15.71.tar.gz";
          hash = "sha256-yhO2cXIeIgUxkSZf/4aAsF11uxyh+UUZu6D1h92vCD8=";
        };
        extraPatchPhase = ''
          ${openwrt.applyPatches.ramips}
        '';
        config = {

          RALINK = "y";
          PCI = "y";
          SOC_MT7620 = "y";

          SERIAL_8250_CONSOLE = "y";
          SERIAL_8250 = "y";
          SERIAL_CORE_CONSOLE = "y";
          SERIAL_OF_PLATFORM = "y";

          CONSOLE_LOGLEVEL_DEFAULT = "8";
          CONSOLE_LOGLEVEL_QUIET = "4";

          NET = "y";
          ETHERNET = "y";
          NET_VENDOR_RALINK = "y";
          NET_RALINK_MDIO = "y";
          NET_RALINK_MDIO_MT7620 = "y";
          NET_RALINK_MT7620 = "y";
          SWPHY = "y";

          SPI = "y";
          MTD_SPI_NOR = "y";
          SPI_MT7621 = "y"; # } probably don't need both of these
          SPI_RT2880 = "y"; # }
          SPI_MASTER= "y";
          SPI_MEM= "y";

          MTD = "y";
          MTD_BLOCK = "y";         # fix undefined ref to register_mtd_blktrans_devs

          EARLY_PRINTK = "y";

          NEW_LEDS = "y";
          LEDS_CLASS = "y";         # required by rt2x00lib

          PRINTK_TIME = "y";
        } // lib.optionalAttrs (config.system.service ? vlan) {
          SWCONFIG = "y";
        };
      };
    };
}