scripts: ci: introduce soc name check in check_compliance

soc.yml files define SoC names which are used in board.yml.
All SoC names and directories are exported to the build system and
can be referenced using the SoC name as identifier.

Kconfig defines a CONFIG_SOC setting with the same name which can be
used in build system and is selected by the board.

Thus the CONFIG_SOC value can be used to lookup the details of the SoC.

This commit introduces a new compliance check which ensures the SoC name
and the CONFIG_SOC name value are in sync.

Signed-off-by: Torsten Rasmussen <Torsten.Rasmussen@nordicsemi.no>

scripts/ci/check_compliance.py

@@ -285,6 +285,7 @@ class KconfigCheck(ComplianceTest):
         self.check_no_undef_within_kconfig(kconf)
         self.check_no_redefined_in_defconfig(kconf)
         self.check_no_enable_in_boolean_prompt(kconf)
+        self.check_soc_name_sync(kconf)
         if full:
             self.check_no_undef_outside_kconfig(kconf)
 
@@ -658,6 +659,34 @@ https://docs.zephyrproject.org/latest/build/kconfig/tips.html#menuconfig-symbols
         if undef_ref_warnings:
             self.failure(f"Undefined Kconfig symbols:\n\n {undef_ref_warnings}")
 
+    def check_soc_name_sync(self, kconf):
+        root_args = argparse.Namespace(**{'soc_roots': [Path(ZEPHYR_BASE)]})
+        v2_systems = list_hardware.find_v2_systems(root_args)
+
+        soc_names = {soc.name for soc in v2_systems.get_socs()}
+
+        soc_kconfig_names = set()
+        for node in kconf.node_iter():
+            # 'kconfiglib' is global
+            # pylint: disable=undefined-variable
+            if isinstance(node.item, kconfiglib.Symbol) and node.item.name == "SOC":
+                n = node.item
+                for d in n.defaults:
+                    soc_kconfig_names.add(d[0].name)
+
+        soc_name_warnings = []
+        for name in soc_names:
+            if name not in soc_kconfig_names:
+                soc_name_warnings.append(f"soc name: {name} not found in CONFIG_SOC defaults.")
+
+        if soc_name_warnings:
+            soc_name_warning_str = '\n'.join(soc_name_warnings)
+            self.failure(f'''
+Missing SoC names or CONFIG_SOC vs soc.yml out of sync:
+
+{soc_name_warning_str}
+''')
+
     def check_no_undef_outside_kconfig(self, kconf):
         """
         Checks that there are no references to undefined Kconfig symbols