cheribsd: Overhaul freebsd-univere and add cheribsd-universe

These are a bit awkward since we need the notion of a FreeBSD/CheriBSD
target without a specific CPU, and these are targets that the base
classes do not themselves support.

Also split tinderbox into separate targets as, whilst universe is the
base Makefile target, tinderbox is its own first-class thing, and it's
more natural to be able to run cheribuild cheribsd-tinderbox.

Author: jrtc27

pycheribuild/config/compilation_targets.py

@@ -408,7 +408,7 @@ def _get_sdk_root_dir_lazy(self) -> Path:
         xtarget = self.target.get_rootfs_target()
         # We don't want to call setup() yet on the FreeBSD instance (not needed to get the compiler)
         # noinspection PyProtectedMember
-        fbsd = self._get_rootfs_class(xtarget)._get_instance_no_setup(self.project, cross_target=xtarget)
+        fbsd = self._get_sdk_root_class(xtarget)._get_instance_no_setup(self.project, cross_target=xtarget)
         configured_path = fbsd.build_toolchain_root_dir  # pytype: disable=attribute-error
         if configured_path is None:
             # If we couldn't find a working system compiler, default to cheribuild-compiled upstream LLVM.
@@ -439,6 +439,7 @@ def is_freebsd(cls) -> bool:
 
     @classmethod
     def triple_for_target(cls, target: "CrossCompileTarget", config: "CheriConfig", *, include_version: bool):
+        assert not target.is_nocpu()
         common_suffix = "-unknown-freebsd"
         if include_version:
             common_suffix += str(cls.FREEBSD_VERSION)
@@ -514,6 +515,11 @@ def localbase(self) -> Path:
     def _get_rootfs_class(self, xtarget: "CrossCompileTarget") -> "type[SimpleProject]":
         return SimpleProject.get_class_for_target_name("freebsd", xtarget)
 
+    def _get_sdk_root_class(self, xtarget: "CrossCompileTarget") -> "type[SimpleProject]":
+        if xtarget.is_nocpu():
+            return SimpleProject.get_class_for_target_name("freebsd-universe", xtarget)
+        return self._get_rootfs_class(xtarget)
+
     def _get_run_project(self, xtarget: "CrossCompileTarget", caller: AbstractProject) -> LaunchFreeBSDInterface:
         result = SimpleProject.get_instance_for_target_name("run-freebsd", xtarget, caller.config, caller)
         return typing.cast(LaunchFreeBSDInterface, result)
@@ -758,6 +764,11 @@ def pkgconfig_dirs(self) -> "list[str]":
     def _get_rootfs_class(self, xtarget: "CrossCompileTarget") -> "type[SimpleProject]":
         return SimpleProject.get_class_for_target_name("cheribsd", xtarget)
 
+    def _get_sdk_root_class(self, xtarget: "CrossCompileTarget") -> "type[SimpleProject]":
+        if xtarget.is_nocpu():
+            return SimpleProject.get_class_for_target_name("cheribsd-universe", xtarget)
+        return self._get_rootfs_class(xtarget)
+
     def cheribsd_version(self) -> "Optional[int]":
         return sys_param_h_cheribsd_version(self.sysroot_dir)
 
@@ -1769,6 +1780,10 @@ class CompilationTargets(BasicCompilationTargets):
         ALL_SUPPORTED_CHERIBSD_AND_HOST_TARGETS + ALL_SUPPORTED_BAREMETAL_TARGETS
     )
 
+    # Special targets for use in freebsd/cheribsd-universe
+    CHERIBSD_NOCPU = CrossCompileTarget("nocpu", CPUArchitecture.NOCPU, CheriBSDTargetInfo)
+    FREEBSD_NOCPU = CrossCompileTarget("nocpu", CPUArchitecture.NOCPU, FreeBSDTargetInfo)
+
     @staticmethod
     def _dump_cheribsd_target_relations() -> None:
         for target in (

pycheribuild/config/target_info.py

@@ -67,6 +67,7 @@ class CPUArchitecture(Enum):
     RISCV32 = "riscv32"
     RISCV64 = "riscv64"
     X86_64 = "x86_64"
+    NOCPU = "nocpu"
 
     def word_bits(self) -> int:
         mapping = {
@@ -87,6 +88,7 @@ def is_64bit(self) -> bool:
         return self.word_bits() == 64
 
     def as_meson_cpu_family(self) -> str:
+        assert self is not CPUArchitecture.NOCPU
         # https://mesonbuild.com/Reference-tables.html#cpu-families
         if self is CPUArchitecture.I386:
             return "x86"
@@ -96,6 +98,7 @@ def as_meson_cpu_family(self) -> str:
         return str(self.value)
 
     def endianess(self) -> str:
+        assert self is not CPUArchitecture.NOCPU
         # Meson expects us to pass this manually... Why not query the compiler???
         if self is CPUArchitecture.MIPS64:
             return "big"
@@ -1050,6 +1053,9 @@ def _check_arch(self, arch: CPUArchitecture, include_purecap: "Optional[bool]")
         return True
 
     # Querying the CPU architecture:
+    def is_nocpu(self, include_purecap: Optional[bool] = None) -> bool:
+        return self._check_arch(CPUArchitecture.NOCPU, include_purecap)
+
     def is_mips(self, include_purecap: Optional[bool] = None) -> bool:
         return self._check_arch(CPUArchitecture.MIPS64, include_purecap)