From a1df417e74aa6dae7352dc8cbb0ad471af5b7c69 Mon Sep 17 00:00:00 2001
From: "Michael J. Chudobiak" <mjc@avtechpulse.com>
Date: Mon, 25 Apr 2016 10:00:44 -0400
Subject: initial Olimex linux tree from Daniel, originally Feb 3, 2016

---
 linux/lib/int_sqrt.c | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)
 create mode 100644 linux/lib/int_sqrt.c

(limited to 'linux/lib/int_sqrt.c')

diff --git a/linux/lib/int_sqrt.c b/linux/lib/int_sqrt.c
new file mode 100644
index 00000000..1ef4cc34
--- /dev/null
+++ b/linux/lib/int_sqrt.c
@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2013 Davidlohr Bueso <davidlohr.bueso@hp.com>
+ *
+ *  Based on the shift-and-subtract algorithm for computing integer
+ *  square root from Guy L. Steele.
+ */
+
+#include <linux/kernel.h>
+#include <linux/export.h>
+
+/**
+ * int_sqrt - rough approximation to sqrt
+ * @x: integer of which to calculate the sqrt
+ *
+ * A very rough approximation to the sqrt() function.
+ */
+unsigned long int_sqrt(unsigned long x)
+{
+	unsigned long b, m, y = 0;
+
+	if (x <= 1)
+		return x;
+
+	m = 1UL << (BITS_PER_LONG - 2);
+	while (m != 0) {
+		b = y + m;
+		y >>= 1;
+
+		if (x >= b) {
+			x -= b;
+			y += m;
+		}
+		m >>= 2;
+	}
+
+	return y;
+}
+EXPORT_SYMBOL(int_sqrt);
-- 
cgit