From 3829ce4ce7664d57cebe3367d27846d8c5f865de Mon Sep 17 00:00:00 2001
From: Adam Joseph <adam@westernsemico.com>
Date: Sun, 29 Oct 2023 22:21:06 -0700
Subject: [PATCH] lib.systems.inspect: deprecate isEfi

This predicate never did what it claimed.

(U)EFI support is a property of a specific motherboard, not of a
platform or an entire architecture.  This predicate was used only by
two packages.  This commit relocates the data previously held by
`inspect.isEfi` to the `meta.platforms` of `gnu-efi` and the
`withEfi` default value of `systemd`.

We need to make room for `isEfi` (or perhaps `isUefi`) in
preparation for https://github.com/NixOS/nixpkgs/pull/231951 so we
should start the deprecation process sooner rather than later.
---
 lib/systems/inspect.nix                       | 22 ++++++++++++++++++-
 .../development/libraries/gnu-efi/default.nix |  4 +++-
 pkgs/os-specific/linux/systemd/default.nix    |  4 ++--
 pkgs/top-level/all-packages.nix               |  4 +---
 4 files changed, 27 insertions(+), 7 deletions(-)

diff --git a/lib/systems/inspect.nix b/lib/systems/inspect.nix
index 022e459c3945a..7a52e94acfdd1 100644
--- a/lib/systems/inspect.nix
+++ b/lib/systems/inspect.nix
@@ -6,7 +6,7 @@ with lib.lists;
 let abis_ = abis; in
 let abis = lib.mapAttrs (_: abi: builtins.removeAttrs abi [ "assertions" ]) abis_; in
 
-rec {
+let result = rec {
   # these patterns are to be matched against {host,build,target}Platform.parsed
   patterns = rec {
     # The patterns below are lists in sum-of-products form.
@@ -31,9 +31,11 @@ rec {
     ];
     isx86          = { cpu = { family = "x86"; }; };
     isAarch32      = { cpu = { family = "arm"; bits = 32; }; };
+    isArmv6        = { cpu = { family = "arm"; version = "6"; }; };
     isArmv7        = map ({ arch, ... }: { cpu = { inherit arch; }; })
                        (lib.filter (cpu: lib.hasPrefix "armv7" cpu.arch or "")
                          (lib.attrValues cpuTypes));
+    isArmv8        = { cpu = { family = "arm"; version = "8"; }; };
     isAarch64      = { cpu = { family = "arm"; bits = 64; }; };
     isAarch        = { cpu = { family = "arm"; }; };
     isMicroBlaze   = { cpu = { family = "microblaze"; }; };
@@ -114,4 +116,22 @@ rec {
   platformPatterns = mapAttrs (_: p: { parsed = {}; } // p) {
     isStatic = { isStatic = true; };
   };
+};
+
+warnEfiDeprecated = throw "(U)EFI support is a feature of specific motherboards rather than entire architectures or platforms; this predicate has been deprecated because its name is misleading";
+
+in
+result // {
+  patterns = result.patterns // {
+    isEfi = warnEfiDeprecated result.patterns.isEfi;
+  };
+
+  # Unfortunately a strictness bug in lib.systems.equals means that
+  # we can't lib.warn on accesses to boolean values.  If
+  # https://github.com/NixOS/nixpkgs/pull/238331 is merged we can go
+  # back to using Nix `==` and this warning can be enabled.
+  #
+  #predicates = result.predicates // {
+  #  isEfi = argument: warnEfiDeprecated (result.predicates.isEfi argument);
+  #};
 }
diff --git a/pkgs/development/libraries/gnu-efi/default.nix b/pkgs/development/libraries/gnu-efi/default.nix
index e9746271ea27e..81a8c98bd2f8a 100644
--- a/pkgs/development/libraries/gnu-efi/default.nix
+++ b/pkgs/development/libraries/gnu-efi/default.nix
@@ -34,7 +34,9 @@ stdenv.mkDerivation rec {
     description = "GNU EFI development toolchain";
     homepage = "https://sourceforge.net/projects/gnu-efi/";
     license = licenses.bsd3;
-    platforms = platforms.linux;
+    platforms = with lib.systems.inspect.patterns; map (pat: pat // isLinux) ([
+      isArmv6 ] ++ isArmv7 ++ [ isArmv8 isRiscV isx86
+    ]);
     maintainers = with maintainers; [ ];
   };
 }
diff --git a/pkgs/os-specific/linux/systemd/default.nix b/pkgs/os-specific/linux/systemd/default.nix
index 01054fa7fc6b2..a7772abb8039e 100644
--- a/pkgs/os-specific/linux/systemd/default.nix
+++ b/pkgs/os-specific/linux/systemd/default.nix
@@ -94,7 +94,7 @@
 , withCryptsetup ? true
 , withRepart ? true
 , withDocumentation ? true
-, withEfi ? stdenv.hostPlatform.isEfi
+, withEfi ? with stdenv.hostPlatform; isArmv6 || isArmv7 || isArmv8 || isRiscV || isx86
 , withFido2 ? true
 , withFirstboot ? false # conflicts with the NixOS /etc management
 , withHomed ? !stdenv.hostPlatform.isMusl
@@ -756,7 +756,7 @@ stdenv.mkDerivation (finalAttrs: {
     # runtime; otherwise we can't and we need to reboot.
     interfaceVersion = 2;
 
-    inherit withCryptsetup withHostnamed withImportd withKmod withLocaled withMachined withPortabled withTimedated withUtmp util-linux kmod kbd;
+    inherit withCryptsetup withHostnamed withImportd withKmod withLocaled withMachined withPortabled withTimedated withUtmp util-linux kmod kbd withEfi;
 
     tests = {
       inherit (nixosTests) switchTest;
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index b0150c6bca6d9..afab46156cbd0 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -21804,9 +21804,7 @@ with pkgs;
 
   gnu-config = callPackage ../development/libraries/gnu-config { };
 
-  gnu-efi = if stdenv.hostPlatform.isEfi
-              then callPackage ../development/libraries/gnu-efi { }
-            else null;
+  gnu-efi = callPackage ../development/libraries/gnu-efi { };
 
   gnutls = callPackage ../development/libraries/gnutls {
     inherit (darwin.apple_sdk.frameworks) Security;