test: math: port window CMocka test to ztest

test/ztest/unit/math/window/CMakeLists.txt

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+# SPDX-License-Identifier: BSD-3-Clause
+#
+# Copyright(c) 2026 Intel Corporation.
+
+cmake_minimum_required(VERSION 3.20.0)
+
+find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
+project(sof_unit_math_window)
+
+set(SOF_ROOT "${PROJECT_SOURCE_DIR}/../../../../..")
+
+target_include_directories(app PRIVATE
+	${SOF_ROOT}/zephyr/include
+	${SOF_ROOT}/src/include
+	# Reference windows are #included in place from the CMocka tree rather
+	# than copied, so both frameworks share identical data.
+	${SOF_ROOT}/test/cmocka/src/math/window
+)
+
+target_compile_definitions(app PRIVATE
+	-DCONFIG_ZEPHYR_POSIX=1
+	-DCONFIG_LIBRARY=1
+	-DUNIT_TEST=1
+)
+
+target_sources(app PRIVATE
+	test_window_ztest.c
+	${SOF_ROOT}/src/math/window.c
+	${SOF_ROOT}/src/math/trig.c
+	${SOF_ROOT}/src/math/log_e.c
+	${SOF_ROOT}/src/math/base2log.c
+	${SOF_ROOT}/src/math/decibels.c
+)
+
+target_link_libraries(app PRIVATE m)

test/ztest/unit/math/window/prj.conf

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+# SPDX-License-Identifier: BSD-3-Clause
+#
+# Copyright(c) 2026 Intel Corporation.
+
+CONFIG_ZTEST=y
+CONFIG_SOF_FULL_ZEPHYR_APPLICATION=n
+# The RMS error is reported and asserted with %f, which printk() and so
+# TC_PRINT() and the zassert() messages only format with FP support enabled
+CONFIG_CBPRINTF_FP_SUPPORT=y

test/ztest/unit/math/window/test_window_ztest.c

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+// SPDX-License-Identifier: BSD-3-Clause
+//
+// Copyright(c) 2026 Intel Corporation.
+//
+// These contents may have been developed with support from one or more
+// Intel-operated generative artificial intelligence solutions.
+//
+// Converted from CMock to Ztest
+// Original tests from test/cmocka/src/math/window/window.c:
+// Author: Seppo Ingalsuo <seppo.ingalsuo@linux.intel.com>
+
+#include <zephyr/ztest.h>
+
+#include <sof/math/window.h>
+
+#include <stdint.h>
+#include <math.h>
+
+/* Reference windows shared with the legacy CMocka test. They are #included
+ * in place from the CMocka tree (added to the include path in CMakeLists.txt)
+ * so the exact same fixed-point data is exercised.
+ */
+#include "ref_window_rectangular.h"
+#include "ref_window_blackman.h"
+#include "ref_window_hamming.h"
+#include "ref_window_povey.h"
+
+/* Maximum tolerated RMS error against the reference, in LSB */
+#define MAX_ERR_RMS 1.0f
+
+/* Scratch window, large enough for the longest reference vector */
+#define MAX_WIN_LENGTH LENGTH_HAMMING
+
+BUILD_ASSERT(LENGTH_RECTANGULAR <= MAX_WIN_LENGTH);
+BUILD_ASSERT(LENGTH_BLACKMAN <= MAX_WIN_LENGTH);
+BUILD_ASSERT(LENGTH_HAMMING <= MAX_WIN_LENGTH);
+BUILD_ASSERT(LENGTH_POVEY <= MAX_WIN_LENGTH);
+
+static int16_t win[MAX_WIN_LENGTH];
+
+/**
+ * @brief Compute the RMS error of a calculated window against its reference.
+ * @param[in] ref_win Reference Q1.15 coefficients.
+ * @param[in] win Calculated Q1.15 coefficients.
+ * @param[in] win_length Number of coefficients to compare.
+ * @return RMS of the per-coefficient error, in LSB.
+ */
+static float window_delta_rms(const int16_t *ref_win, const int16_t *win, int win_length)
+{
+	float err_squared = 0.0;
+	int i;
+
+	for (i = 0; i < win_length; i++) {
+		err_squared +=
+			((float)ref_win[i] - (float)win[i]) * ((float)ref_win[i] - (float)win[i]);
+	}
+
+	return sqrtf(err_squared / (float)win_length);
+}
+
+/**
+ * @brief Check the window left in win[] against a reference vector.
+ * @param[in] window_name Window name, for the test log.
+ * @param[in] ref_win Reference Q1.15 coefficients.
+ * @param[in] window_length Number of coefficients to compare.
+ */
+static void check_window(const char *window_name, const int16_t *ref_win, int window_length)
+{
+	float err_rms = window_delta_rms(ref_win, win, window_length);
+
+	/* printk() is varargs, so the float arguments are promoted to double
+	 * anyway; cast explicitly to keep -Wdouble-promotion quiet.
+	 */
+	TC_PRINT("Window %s RMS error = %5.2f LSB (max %5.2f)\n", window_name, (double)err_rms,
+		 (double)MAX_ERR_RMS);
+
+	zassert_true(err_rms < MAX_ERR_RMS, "Window %s RMS error %5.2f exceeds limit %5.2f",
+		     window_name, (double)err_rms, (double)MAX_ERR_RMS);
+}
+
+/**
+ * @brief Verify the rectangular window against its reference vector
+ */
+ZTEST(math_window_suite, test_math_window_rectangular)
+{
+	win_rectangular_16b(win, LENGTH_RECTANGULAR);
+	check_window("rectangular", ref_rectangular, LENGTH_RECTANGULAR);
+}
+
+/**
+ * @brief Verify the Blackman window against its reference vector
+ */
+ZTEST(math_window_suite, test_math_window_blackman)
+{
+	win_blackman_16b(win, LENGTH_BLACKMAN, WIN_BLACKMAN_A0_Q15);
+	check_window("blackman", ref_blackman, LENGTH_BLACKMAN);
+}
+
+/**
+ * @brief Verify the Hamming window against its reference vector
+ */
+ZTEST(math_window_suite, test_math_window_hamming)
+{
+	win_hamming_16b(win, LENGTH_HAMMING);
+	check_window("hamming", ref_hamming, LENGTH_HAMMING);
+}
+
+/**
+ * @brief Verify the Povey window against its reference vector
+ */
+ZTEST(math_window_suite, test_math_window_povey)
+{
+	win_povey_16b(win, LENGTH_POVEY);
+	check_window("povey", ref_povey, LENGTH_POVEY);
+}
+
+/**
+ * @brief Define and initialize the window function test suite
+ */
+ZTEST_SUITE(math_window_suite, NULL, NULL, NULL, NULL, NULL);

test/ztest/unit/math/window/testcase.yaml

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+# SPDX-License-Identifier: BSD-3-Clause
+#
+# Copyright(c) 2026 Intel Corporation.
+#
+# Math window function unit tests converted from CMock to Ztest
+#
+# These contents may have been developed with support from one or more Intel-operated
+# generative artificial intelligence solutions.
+#
+
+common:
+  tags:
+    - SOF
+    - unit_test
+    - math
+    - window
+  integration_platforms:
+    - native_sim
+  arch_exclude: xtensa
+
+tests:
+  sof.unit.math.window:
+    platform_allow:
+      - native_sim
+    build_only: false