diff --git a/scripts/cmake/misc.cmake b/scripts/cmake/misc.cmake
index ee794780cd09..77ae05ee2754 100644
--- a/scripts/cmake/misc.cmake
+++ b/scripts/cmake/misc.cmake
@@ -49,6 +49,15 @@ macro(is_zephyr ret)
 	endif()
 endmacro()
 
+# This macro
+# - saves a LOT of repetition, and
+# - mimics Zephyr, which helps with compatibility.
+macro(add_local_sources_ifdef condition target)
+	if(${condition})
+		add_local_sources(${target} ${ARGN})
+	endif()
+endmacro()
+
 # Adds sources to target like target_sources, but assumes that
 # paths are relative to subdirectory.
 # Works like:
diff --git a/src/math/CMakeLists.txt b/src/math/CMakeLists.txt
index 899810544864..afbc4718fa59 100644
--- a/src/math/CMakeLists.txt
+++ b/src/math/CMakeLists.txt
@@ -11,49 +11,33 @@ if(CONFIG_CORDIC_FIXED)
         add_local_sources(sof trig.c)
 endif()
 
-if(CONFIG_SQRT_FIXED)
-        add_local_sources(sof sqrt_int16.c)
-endif()
+add_local_sources_ifdef(CONFIG_SQRT_FIXED sof sqrt_int16.c)
 
-if(CONFIG_MATH_EXP)
-        add_local_sources(sof exp_fcn.c exp_fcn_hifi.c)
-endif()
+add_local_sources_ifdef(CONFIG_MATH_EXP sof exp_fcn.c exp_fcn_hifi.c)
 
 if(CONFIG_MATH_DECIBELS)
         add_local_sources(sof decibels.c)
 endif()
 
-if(CONFIG_NATURAL_LOGARITHM_FIXED)
-	 add_local_sources(sof log_e.c)
-endif()
+add_local_sources_ifdef(CONFIG_NATURAL_LOGARITHM_FIXED sof log_e.c)
 
-if(CONFIG_COMMON_LOGARITHM_FIXED)
-	 add_local_sources(sof log_10.c)
-endif()
+add_local_sources_ifdef(CONFIG_COMMON_LOGARITHM_FIXED sof log_10.c)
 
-if(CONFIG_POWER_FIXED)
-	 add_local_sources(sof power.c)
-endif()
+add_local_sources_ifdef(CONFIG_POWER_FIXED sof power.c)
 
-if(CONFIG_BINARY_LOGARITHM_FIXED)
-	 add_local_sources(sof base2log.c)
-endif()
+add_local_sources_ifdef(CONFIG_BINARY_LOGARITHM_FIXED sof base2log.c)
 
-if(CONFIG_MATH_FIR)
-        add_local_sources(sof fir_generic.c fir_hifi2ep.c fir_hifi3.c)
-endif()
+add_local_sources_ifdef(CONFIG_MATH_FIR sof fir_generic.c fir_hifi2ep.c fir_hifi3.c)
 
 if(CONFIG_MATH_FFT)
 	add_subdirectory(fft)
 endif()
 
-if(CONFIG_MATH_IIR_DF2T)
-        add_local_sources(sof iir_df2t_generic.c iir_df2t_hifi3.c iir_df2t.c)
-endif()
+add_local_sources_ifdef(CONFIG_MATH_IIR_DF2T sof
+	iir_df2t_generic.c iir_df2t_hifi3.c iir_df2t.c)
 
-if(CONFIG_MATH_IIR_DF1)
-        add_local_sources(sof iir_df1_generic.c iir_df1_hifi3.c iir_df1.c)
-endif()
+add_local_sources_ifdef(CONFIG_MATH_IIR_DF1 sof
+	iir_df1_generic.c iir_df1_hifi3.c iir_df1.c)
 
 if(CONFIG_MATH_WINDOW)
 	 add_local_sources(sof window.c)
diff --git a/src/math/auditory/CMakeLists.txt b/src/math/auditory/CMakeLists.txt
index c94aed430040..2983e1eb4483 100644
--- a/src/math/auditory/CMakeLists.txt
+++ b/src/math/auditory/CMakeLists.txt
@@ -2,10 +2,6 @@
 
 add_local_sources(sof auditory.c)
 
-if(CONFIG_MATH_16BIT_MEL_FILTERBANK)
-        add_local_sources(sof mel_filterbank_16.c)
-endif()
+add_local_sources_ifdef(CONFIG_MATH_16BIT_MEL_FILTERBANK sof mel_filterbank_16.c)
 
-if(CONFIG_MATH_32BIT_MEL_FILTERBANK)
-        add_local_sources(sof mel_filterbank_32.c)
-endif()
+add_local_sources_ifdef(CONFIG_MATH_32BIT_MEL_FILTERBANK sof mel_filterbank_32.c)
diff --git a/src/math/fft/CMakeLists.txt b/src/math/fft/CMakeLists.txt
index e196f54fa0e9..8d422b93c5b1 100644
--- a/src/math/fft/CMakeLists.txt
+++ b/src/math/fft/CMakeLists.txt
@@ -2,10 +2,6 @@
 
 add_local_sources(sof fft_common.c)
 
-if(CONFIG_MATH_16BIT_FFT)
-        add_local_sources(sof fft_16.c fft_16_hifi3.c)
-endif()
+add_local_sources_ifdef(CONFIG_MATH_16BIT_FFT sof fft_16.c fft_16_hifi3.c)
 
-if(CONFIG_MATH_32BIT_FFT)
-        add_local_sources(sof fft_32.c fft_32_hifi3.c)
-endif()
+add_local_sources_ifdef(CONFIG_MATH_32BIT_FFT sof fft_32.c fft_32_hifi3.c)
diff --git a/src/module/audio/CMakeLists.txt b/src/module/audio/CMakeLists.txt
index 2d805aa68929..06407bab7520 100644
--- a/src/module/audio/CMakeLists.txt
+++ b/src/module/audio/CMakeLists.txt
@@ -1,14 +1,6 @@
 # SPDX-License-Identifier: BSD-3-Clause
 
-is_zephyr(it_is)
-if(it_is)  ### Zephyr ###
-	zephyr_library_sources(
-		source_api.c
-		sink_api.c
-	)
-else()  ### Not Zephyr ###
-	add_local_sources(sof
-		source_api.c
-		sink_api.c
-	)
-endif() # Zephyr
+add_local_sources(sof
+	source_api.c
+	sink_api.c
+)
diff --git a/zephyr/CMakeLists.txt b/zephyr/CMakeLists.txt
index f9e1f3c40e00..a859282102c6 100644
--- a/zephyr/CMakeLists.txt
+++ b/zephyr/CMakeLists.txt
@@ -48,16 +48,17 @@ zephyr_interface_library_named(SOF)
 # SOF source paths.
 cmake_path(SET sof_top_dir NORMALIZE "${CMAKE_CURRENT_SOURCE_DIR}/..")
 set(SOF_SRC_PATH "${sof_top_dir}/src")
+
 set(SOF_PLATFORM_PATH "${SOF_SRC_PATH}/platform")
 set(SOF_AUDIO_PATH "${SOF_SRC_PATH}/audio")
 set(SOF_AUDIO_MODULES_PATH "${SOF_SRC_PATH}/audio/module_adapter/module")
 set(SOF_SAMPLES_PATH "${SOF_SRC_PATH}/samples")
 set(SOF_LIB_PATH "${SOF_SRC_PATH}/lib")
 set(SOF_DRIVERS_PATH "${SOF_SRC_PATH}/drivers")
-set(SOF_IPC_PATH "${SOF_SRC_PATH}/ipc")
 set(SOF_DEBUG_PATH "${SOF_SRC_PATH}/debug")
 set(SOF_MATH_PATH "${SOF_SRC_PATH}/math")
 set(SOF_TRACE_PATH "${SOF_SRC_PATH}/trace")
+
 set(RIMAGE_TOP ${sof_top_dir}/tools/rimage)
 
 # Save path to rimage configuration files in cmake cache for later use by
@@ -127,6 +128,22 @@ macro(is_zephyr ret)
 	endif()
 endmacro()
 
+# Wrappers for compatibility and re-use of existing, XTOS CMake files.
+# Do NOT use these macros in this file or in any other Zephyr-specific
+# CMake code.
+macro(add_local_sources target)
+	if (NOT "${target}" STREQUAL "sof")
+		message(FATAL_ERROR "add_local_sources() target is not 'sof'")
+	endif()
+	zephyr_library_sources(${ARGN})
+endmacro()
+macro(add_local_sources_ifdef condition target)
+	if (NOT "${target}" STREQUAL "sof")
+		message(FATAL_ERROR "add_local_sources_ifdef() target is not 'sof'")
+	endif()
+	zephyr_library_sources_ifdef(${condition} ${ARGN})
+endmacro()
+
 add_subdirectory(../src/init/ init_unused_install/)
 add_subdirectory(../src/ipc/  ipc_unused_install/)