doc: Add option to stub out doxygengroups

doc/CMakeLists.txt

@@ -115,9 +115,19 @@ foreach(root ${DTS_ROOTS})
 endforeach()
 
 if(DT_TURBO_MODE)
+  message(WARNING "DT 'turbo mode' is enabled.\n"
+                  "The index of Devicetree bindings won't be generated and Sphinx roles such as "
+                  ":dtcompatible: won't be able to link to them.")
   list(APPEND DTS_ARGS --turbo-mode)
 endif()
 
+if(DOXYGENGROUPS_TURBO_MODE)
+  message(WARNING "Doxygen groups 'turbo mode' is enabled.\n"
+                  "Doxygen groups won't be rendered in the documentation and Sphinx roles such as "
+                  ":c:func: won't be able to link to them.")
+  list(APPEND SPHINXOPTS_EXTRA -D zephyr_breathe_skip_doxygen_groups=1)
+endif()
+
 add_custom_target(
   devicetree
   COMMAND ${CMAKE_COMMAND} -E env

doc/Makefile

@@ -8,14 +8,15 @@ SPHINXOPTS ?= -j auto -W --keep-going -T
 SPHINXOPTS_EXTRA ?=
 LATEXMKOPTS ?= -halt-on-error -no-shell-escape
 DT_TURBO_MODE ?= 0
+DOXYGENGROUPS_TURBO_MODE ?= 0
 
 # ------------------------------------------------------------------------------
 # Documentation targets
 
 .PHONY: configure clean html html-fast latex pdf doxygen
 
 html-fast:
-	${MAKE} html DT_TURBO_MODE=1
+	${MAKE} html DT_TURBO_MODE=1 DOXYGENGROUPS_TURBO_MODE=1
 
 html latex pdf linkcheck doxygen: configure
 	cmake --build ${BUILDDIR} --target $@
@@ -29,7 +30,8 @@ configure:
 		-DSPHINXOPTS="${SPHINXOPTS}" \
 		-DSPHINXOPTS_EXTRA="${SPHINXOPTS_EXTRA}" \
 		-DLATEXMKOPTS="${LATEXMKOPTS}" \
-		-DDT_TURBO_MODE=${DT_TURBO_MODE}
+		-DDT_TURBO_MODE=${DT_TURBO_MODE} \
+		-DDOXYGENGROUPS_TURBO_MODE=${DOXYGENGROUPS_TURBO_MODE}
 
 clean:
 	cmake --build ${BUILDDIR} --target clean

doc/_extensions/zephyr/domain.py

@@ -307,16 +307,25 @@ class CustomDoxygenGroupDirective(DoxygenGroupDirective):
     """Monkey patch for Breathe's DoxygenGroupDirective."""
 
     def run(self) -> List[Node]:
-        nodes = super().run()
+        if self.config.zephyr_breathe_skip_doxygen_groups:
+            note = nodes.attention()
+            note += nodes.Text(
+                f"Doxygen group {self.arguments[0]} was excluded from the documentation."
+            )
+
+            doxygengroup_node = [note]
+        else:
+            doxygengroup_node = super().run()
 
         if self.config.zephyr_breathe_insert_related_samples:
-            return [RelatedCodeSamplesNode(id=self.arguments[0]), *nodes]
+            return [RelatedCodeSamplesNode(id=self.arguments[0]), *doxygengroup_node]
         else:
-            return nodes
+            return doxygengroup_node
 
 
 def setup(app):
     app.add_config_value("zephyr_breathe_insert_related_samples", False, "env")
+    app.add_config_value("zephyr_breathe_skip_doxygen_groups", False, "env")
 
     app.add_domain(ZephyrDomain)
 

doc/contribute/documentation/generation.rst

@@ -264,18 +264,17 @@ Developer-mode Document Building
 ********************************
 
 When making and testing major changes to the documentation, we provide an option
-to temporarily stub-out the auto-generated Devicetree bindings documentation so
-the doc build process runs faster.
+to temporarily stub-out some of the more time-consuming parts of the build, such
+as cross references to Doxygen-generated content, or Devicetree bindings
+documentation, so that the doc build process runs faster.
 
-To enable this mode, set the following option when invoking cmake::
+To enable this mode, set the following options when invoking cmake::
 
-   -DDT_TURBO_MODE=1
+   -DDT_TURBO_MODE=1 -DDOXYGENGROUPS_TURBO_MODE=1
 
 or invoke make with the following target::
 
    cd ~/zephyr
-
-   # To generate HTML output without detailed Kconfig
    make html-fast
 
 Viewing generated documentation locally