nixos-config/hosts/aarch64-linux/alastor/apple-silicon-support/packages/linux-asahi/default.nix

{
  lib,
  pkgs,
  callPackage,
  writeShellScriptBin,
  writeText,
  removeReferencesTo,
  linuxPackagesFor,
  withRust ? false,
  _kernelPatches ? [],
}: let
  i = builtins.elemAt;

  # parse <OPT> [ymn]|foo style configuration as found in a patch's extraConfig
  # into a list of k, v tuples
  parseExtraConfig = config: let
    lines =
      builtins.filter (s: s != "") (lib.strings.splitString "\n" config);
    parseLine = line: let
      t = lib.strings.splitString " " line;
      join = l:
        builtins.foldl' (a: b: "${a} ${b}")
        (builtins.head l) (builtins.tail l);
      v =
        if (builtins.length t) > 2
        then join (builtins.tail t)
        else (i t 1);
    in ["CONFIG_${i t 0}" v];
  in
    map parseLine lines;

  # parse <OPT>=lib.kernel.(yes|module|no)|lib.kernel.freeform "foo"
  # style configuration as found in a patch's extraStructuredConfig into
  # a list of k, v tuples
  parseExtraStructuredConfig = config:
    lib.attrsets.mapAttrsToList
    (k: v: ["CONFIG_${k}" (v.tristate or v.freeform)])
    config;

  parsePatchConfig = {
    extraConfig ? "",
    extraStructuredConfig ? {},
    ...
  }:
    (parseExtraConfig extraConfig)
    ++ (parseExtraStructuredConfig extraStructuredConfig);

  # parse CONFIG_<OPT>=[ymn]|"foo" style configuration as found in a config file
  # into a list of k, v tuples
  parseConfig = config: let
    parseLine = builtins.match ''(CONFIG_[[:upper:][:digit:]_]+)=(([ymn])|"([^"]*)")'';
    # get either the [ymn] option or the "foo" option; whichever matched
    t = l: let
      v = i l 2;
    in [
      (i l 0)
      (
        if v != null
        then v
        else (i l 3)
      )
    ];
    lines = lib.strings.splitString "\n" config;
  in
    map t (builtins.filter (l: l != null) (map parseLine lines));

  origConfigfile = ./config;

  linux-asahi-pkg = {
    stdenv,
    lib,
    fetchFromGitHub,
    fetchpatch,
    linuxKernel,
    rustPlatform,
    rustc,
    rustfmt,
    rust-bindgen,
    ...
  } @ args: let
    origConfigText = builtins.readFile origConfigfile;

    # extraConfig from all patches in order
    extraConfig =
      lib.fold (patch: ex: ex ++ (parsePatchConfig patch)) [] _kernelPatches;
    # config file text for above
    extraConfigText = let
      text = k: v:
        if (v == "y") || (v == "m") || (v == "n")
        then "${k}=${v}"
        else ''${k}="${v}"'';
    in (map (t: text (i t 0) (i t 1)) extraConfig);

    # final config as a text file path
    configfile =
      if extraConfig == []
      then origConfigfile
      else
        writeText "config" ''
          ${origConfigText}

          # Patches
          ${lib.strings.concatStringsSep "\n" extraConfigText}
        '';
    # final config as an attrset
    configAttrs = let
      makePair = t: lib.nameValuePair (i t 0) (i t 1);
      configList = (parseConfig origConfigText) ++ extraConfig;
    in
      builtins.listToAttrs (map makePair (lib.lists.reverseList configList));

    # used to (ostensibly) keep compatibility for those running stable versions of nixos
    rustOlder = version: withRust && (lib.versionOlder rustc.version version);
    bindgenOlder = version: withRust && (lib.versionOlder rust-bindgen.unwrapped.version version);

    # used to fix issues when nixpkgs gets ahead of the kernel
    rustAtLeast = version: withRust && (lib.versionAtLeast rustc.version version);
    bindgenAtLeast = version: withRust && (lib.versionAtLeast rust-bindgen.unwrapped.version version);
  in
    (linuxKernel.manualConfig rec {
        inherit stdenv lib;

        version = "6.6.0-asahi";
        modDirVersion = version;
        extraMeta.branch = "6.6";

        src = fetchFromGitHub {
          # tracking: https://github.com/AsahiLinux/linux/tree/asahi-wip (w/ fedora verification)
          owner = "AsahiLinux";
          repo = "linux";
          rev = "asahi-6.6-15";
          hash = "sha256-Jm7wTKWuwd/6ZN0g5F4CNNETiOyGQL31hfSyTDYH85k=";
        };

        kernelPatches =
          [
            {
              name = "coreutils-fix";
              patch = ./0001-fs-fcntl-accept-more-values-as-F_DUPFD_CLOEXEC-args.patch;
            }
            # speaker enablement; we assert on the relevant lsp-plugins patch
            # before installing speakersafetyd to let the speakers work
            {
              name = "speakers-1";
              patch = fetchpatch {
                url = "https://github.com/AsahiLinux/linux/commit/385ea7b5023486aba7919cec8b6b3f6a843a1013.patch";
                hash = "sha256-u7IzhJbUgBPfhJXAcpHw1I6OPzPHc1UKYjH91Ep3QHQ=";
              };
            }
            {
              name = "speakers-2";
              patch = fetchpatch {
                url = "https://github.com/AsahiLinux/linux/commit/6a24102c06c95951ab992e2d41336cc6d4bfdf23.patch";
                hash = "sha256-wn5x2hN42/kCp/XHBvLWeNLfwlOBB+T6UeeMt2tSg3o=";
              };
            }
          ]
          ++ lib.optionals (rustAtLeast "1.75.0") [
            {
              name = "rustc-1.75.0";
              patch = ./0001-check-in-new-alloc-for-1.75.0.patch;
            }
          ]
          ++ lib.optionals (rustAtLeast "1.76.0") [
            {
              name = "rustc-1.76.0";
              patch = ./rust_1_76_0.patch;
            }
          ]
          ++ _kernelPatches;

        inherit configfile;
        # hide Rust support from the nixpkgs infra to avoid it re-adding the rust packages.
        # we can't use it until it's in stable and until we've evaluated the cross-compilation impact.
        config = configAttrs // {"CONFIG_RUST" = "n";};
      }
      // (args.argsOverride or {}))
    .overrideAttrs (old:
      if withRust
      then {
        nativeBuildInputs =
          (old.nativeBuildInputs or [])
          ++ [
            rust-bindgen
            rustfmt
            rustc
            removeReferencesTo
          ];
        # HACK: references shouldn't have been there in the first place
        # TODO: remove once 23.05 is obsolete
        postFixup =
          (old.postFixup or "")
          + ''
            if [ -f $dev/lib/modules/${old.version}/build/vmlinux ]; then
              remove-references-to -t $out $dev/lib/modules/${old.version}/build/vmlinux
            fi
            remove-references-to -t $dev $out/Image
          '';
        RUST_LIB_SRC = rustPlatform.rustLibSrc;
      }
      else {});

  linux-asahi = callPackage linux-asahi-pkg {};
in
  lib.recurseIntoAttrs (linuxPackagesFor linux-asahi)