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diff --git a/include/linux/int_log.h b/include/linux/int_log.h
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+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Provides fixed-point logarithm operations.
+ *
+ * Copyright (C) 2006 Christoph Pfister (christophpfister@gmail.com)
+ */
+
+#ifndef __LINUX_INT_LOG_H
+#define __LINUX_INT_LOG_H
+
+#include <linux/types.h>
+
+/**
+ * intlog2 - computes log2 of a value; the result is shifted left by 24 bits
+ *
+ * @value: The value (must be != 0)
+ *
+ * to use rational values you can use the following method:
+ *
+ *   intlog2(value) = intlog2(value * 2^x) - x * 2^24
+ *
+ * Some usecase examples:
+ *
+ *	intlog2(8) will give 3 << 24 = 3 * 2^24
+ *
+ *	intlog2(9) will give 3 << 24 + ... = 3.16... * 2^24
+ *
+ *	intlog2(1.5) = intlog2(3) - 2^24 = 0.584... * 2^24
+ *
+ *
+ * return: log2(value) * 2^24
+ */
+extern unsigned int intlog2(u32 value);
+
+/**
+ * intlog10 - computes log10 of a value; the result is shifted left by 24 bits
+ *
+ * @value: The value (must be != 0)
+ *
+ * to use rational values you can use the following method:
+ *
+ *   intlog10(value) = intlog10(value * 10^x) - x * 2^24
+ *
+ * An usecase example:
+ *
+ *	intlog10(1000) will give 3 << 24 = 3 * 2^24
+ *
+ *   due to the implementation intlog10(1000) might be not exactly 3 * 2^24
+ *
+ * look at intlog2 for similar examples
+ *
+ * return: log10(value) * 2^24
+ */
+extern unsigned int intlog10(u32 value);
+
+#endif