lib, treewide: Add missing MIPS arches, and fix existing usage

Existing "mips64el" should be "mipsel".

This is just the barest minimum so that nixpkgs can recognize them as
systems - although required for building individual derivations onto
MIPS boards, it is not sufficient if you want to actually build nixos on
those targets

doc/meta.xml

···
                 "x86_64-linux",
                 "armv5tel-linux",
                 "armv7l-linux",
-                "mips64el-linux",
+                "mips32-linux",
                 "x86_64-darwin",
                 "i686-cygwin",
                 "i686-freebsd",

lib/systems/doubles.nix

···
     "aarch64-linux"
     "armv5tel-linux" "armv6l-linux" "armv7l-linux"
 
-    "mips64el-linux"
+    "mipsel-linux"
 
     "i686-cygwin" "i686-freebsd" "i686-linux" "i686-netbsd" "i686-openbsd"
 

lib/systems/examples.nix

···
   };
 
   fuloongminipc = rec {
-    config = "mips64el-unknown-linux-gnu";
+    config = "mipsel-unknown-linux-gnu";
     arch = "mips";
     float = "hard";
     platform = platforms.fuloong2f_n32;

lib/systems/parse.nix

···
     aarch64  = { bits = 64; significantByte = littleEndian; family = "aarch64"; };
     i686     = { bits = 32; significantByte = littleEndian; family = "x86"; };
     x86_64   = { bits = 64; significantByte = littleEndian; family = "x86"; };
-    mips64el = { bits = 32; significantByte = littleEndian; family = "mips"; };
+    mips     = { bits = 32; significantByte = bigEndian;    family = "mips"; };
+    mipsel   = { bits = 32; significantByte = littleEndian; family = "mips"; };
+    mips64   = { bits = 64; significantByte = bigEndian;    family = "mips"; };
+    mips64el = { bits = 64; significantByte = littleEndian; family = "mips"; };
     powerpc  = { bits = 32; significantByte = bigEndian;    family = "power"; };
     riscv32  = { bits = 32; significantByte = littleEndian; family = "riscv"; };
     riscv64  = { bits = 64; significantByte = littleEndian; family = "riscv"; };

lib/systems/platforms.nix

···
       "armv6l-linux" = raspberrypi;
       "armv7l-linux" = armv7l-hf-multiplatform;
       "aarch64-linux" = aarch64-multiplatform;
-      "mips64el-linux" = fuloong2f_n32;
+      "mipsel-linux" = fuloong2f_n32;
     }.${system} or pcBase;
 }

lib/tests/systems.nix

···
 
   arm = assertTrue (mseteq arm [ "armv5tel-linux" "armv6l-linux" "armv7l-linux" ]);
   i686 = assertTrue (mseteq i686 [ "i686-linux" "i686-freebsd" "i686-netbsd" "i686-openbsd" "i686-cygwin" ]);
-  mips = assertTrue (mseteq mips [ "mips64el-linux" ]);
+  mips = assertTrue (mseteq mips [ "mipsel-linux" ]);
   x86_64 = assertTrue (mseteq x86_64 [ "x86_64-linux" "x86_64-darwin" "x86_64-freebsd" "x86_64-openbsd" "x86_64-netbsd" "x86_64-cygwin" "x86_64-solaris" ]);
 
   cygwin = assertTrue (mseteq cygwin [ "i686-cygwin" "x86_64-cygwin" ]);
···
   freebsd = assertTrue (mseteq freebsd [ "i686-freebsd" "x86_64-freebsd" ]);
   gnu = assertTrue (mseteq gnu (linux /* ++ hurd ++ kfreebsd ++ ... */));
   illumos = assertTrue (mseteq illumos [ "x86_64-solaris" ]);
-  linux = assertTrue (mseteq linux [ "i686-linux" "x86_64-linux" "armv5tel-linux" "armv6l-linux" "armv7l-linux" "aarch64-linux" "mips64el-linux" ]);
+  linux = assertTrue (mseteq linux [ "i686-linux" "x86_64-linux" "armv5tel-linux" "armv6l-linux" "armv7l-linux" "aarch64-linux" "mipsel-linux" ]);
   netbsd = assertTrue (mseteq netbsd [ "i686-netbsd" "x86_64-netbsd" ]);
   openbsd = assertTrue (mseteq openbsd [ "i686-openbsd" "x86_64-openbsd" ]);
   unix = assertTrue (mseteq unix (linux ++ darwin ++ freebsd ++ openbsd ++ netbsd ++ illumos));

pkgs/build-support/bintools-wrapper/default.nix

···
     else if (with targetPlatform; isArm && isLinux)   then "${libc_lib}/lib/ld-linux*.so.3"
     else if targetPlatform.system == "aarch64-linux"  then "${libc_lib}/lib/ld-linux-aarch64.so.1"
     else if targetPlatform.system == "powerpc-linux"  then "${libc_lib}/lib/ld.so.1"
-    else if targetPlatform.system == "mips64el-linux" then "${libc_lib}/lib/ld.so.1"
+    else if targetPlatform.isMips                     then "${libc_lib}/lib/ld.so.1"
     else if targetPlatform.isDarwin                   then "/usr/lib/dyld"
     else if stdenv.lib.hasSuffix "pc-gnu" targetPlatform.config then "ld.so.1"
     else null;
···
       else if targetPlatform.isWindows then "pe"
       else "elf" + toString targetPlatform.parsed.cpu.bits;
     endianPrefix = if targetPlatform.isBigEndian then "big" else "little";
+    sep = optionalString (targetPlatform.isx86 || targetPlatform.isArm) "-";
     arch =
       /**/ if targetPlatform.isAarch64 then endianPrefix + "aarch64"
       else if targetPlatform.isArm     then endianPrefix + "arm"
       else if targetPlatform.isx86_64  then "x86-64"
       else if targetPlatform.isi686    then "i386"
+      else if targetPlatform.isMips    then {
+          "mips"     = "btsmipn32"; # n32 variant
+          "mipsel"   = "ltsmipn32"; # n32 variant
+          "mips64"   = "btsmip";
+          "mips64el" = "ltsmip";
+        }.${targetPlatform.parsed.cpu.name}
       else throw "unknown emulation for platform: " + targetPlatform.config;
-    in targetPlatform.platform.bfdEmulation or (fmt + "-" + arch);
+    in targetPlatform.platform.bfdEmulation or (fmt + sep + arch);
 
   depsTargetTargetPropagated = extraPackages;
 

pkgs/development/compilers/gcc/4.5/default.nix

···
 
     # Platform-specific flags
     optional (targetPlatform == hostPlatform && targetPlatform.isi686) "--with-arch=i686" ++
-    # Trick that should be taken out once we have a mips64el-linux not loongson2f
-    optional (targetPlatform == hostPlatform && stdenv.system == "mips64el-linux") "--with-arch=loongson2f"
+    # Trick that should be taken out once we have a mipsel-linux not loongson2f
+    optional (targetPlatform == hostPlatform && stdenv.system == "mipsel-linux") "--with-arch=loongson2f"
   ;
 
   targetConfig = if targetPlatform != hostPlatform then targetPlatform.config else null;

pkgs/development/tools/misc/pkgconfig/default.nix

···
   patches = optional (!vanilla) ./requires-private.patch
     ++ optional stdenv.isCygwin ./2.36.3-not-win32.patch;
 
-  preConfigure = optionalString (stdenv.system == "mips64el-linux")
-    ''cp -v ${automake}/share/automake*/config.{sub,guess} .'';
+  preConfigure = ""; # TODO(@Ericson2314): Remove next mass rebuild
   buildInputs = optional (stdenv.isCygwin || stdenv.isDarwin || stdenv.isSunOS) libiconv;
 
   configureFlags = [ "--with-internal-glib" ]

pkgs/os-specific/linux/kbd/default.nix

···
 
       # We get a warning in armv5tel-linux and the fuloong2f, so we
       # disable -Werror in it.
-      ${stdenv.lib.optionalString (stdenv.isArm || stdenv.system == "mips64el-linux") ''
+      ${stdenv.lib.optionalString (stdenv.isArm || stdenv.hostPlatform.isMips) ''
         sed -i s/-Werror// src/Makefile.am
       ''}
     '';

pkgs/stdenv/adapters.nix

···
               # without proper `file` command, libtool sometimes fails
               # to recognize 64-bit DLLs
             ++ stdenv.lib.optional (hostPlatform.config == "x86_64-w64-mingw32") pkgs.file
-            ++ stdenv.lib.optional (hostPlatform.isAarch64 || hostPlatform.libc == "musl") pkgs.updateAutotoolsGnuConfigScriptsHook
+            ++ stdenv.lib.optional
+                 (hostPlatform.isAarch64 || hostPlatform.isMips || hostPlatform.libc == "musl")
+                 pkgs.updateAutotoolsGnuConfigScriptsHook
             ;
 
           crossConfig = hostPlatform.config;

pkgs/stdenv/default.nix

···
     "armv6l-linux" = stagesLinux;
     "armv7l-linux" = stagesLinux;
     "aarch64-linux" = stagesLinux;
-    "mips64el-linux" = stagesLinux;
+    "mipsel-linux" = stagesLinux;
     "powerpc-linux" = /* stagesLinux */ stagesNative;
     "x86_64-darwin" = stagesDarwin;
     "x86_64-solaris" = stagesNix;

pkgs/stdenv/linux/default.nix

···
       "armv6l-linux" = import ./bootstrap-files/armv6l.nix;
       "armv7l-linux" = import ./bootstrap-files/armv7l.nix;
       "aarch64-linux" = import ./bootstrap-files/aarch64.nix;
-      "mips64el-linux" = import ./bootstrap-files/loongson2f.nix;
+      "mipsel-linux" = import ./bootstrap-files/loongson2f.nix;
     };
     "musl" = {
       "aarch64-linux" = import ./bootstrap-files/aarch64-musl.nix;
···
       export NIX_ENFORCE_PURITY="''${NIX_ENFORCE_PURITY-1}"
       export NIX_ENFORCE_NO_NATIVE="''${NIX_ENFORCE_NO_NATIVE-1}"
       ${if system == "x86_64-linux" then "NIX_LIB64_IN_SELF_RPATH=1" else ""}
-      ${if system == "mips64el-linux" then "NIX_LIB32_IN_SELF_RPATH=1" else ""}
+      ${if system == "mipsel-linux" then "NIX_LIB32_IN_SELF_RPATH=1" else ""}
     '';
 
 

pkgs/top-level/all-packages.nix

···
   xbursttools = assert stdenv ? glibc; callPackage ../tools/misc/xburst-tools rec {
     # It needs a cross compiler for mipsel to build the firmware it will
     # load into the Ben Nanonote
-    crossPrefix = "mips64el-unknown-linux-gnu";
+    crossPrefix = "mipsel-unknown-linux-gnu";
     gccCross =
       let
         pkgsCross = nixpkgsFun {