1 files changed, 57 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/omap-common/utils.c b/arch/arm/cpu/armv7/omap-common/utils.c
new file mode 100644
index 000000000..ea935da45
--- /dev/null
+++ b/arch/arm/cpu/armv7/omap-common/utils.c
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2011 Linaro Limited
+ * Aneesh V <aneesh@ti.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+#include <common.h>
+static void do_cancel_out(u32 *num, u32 *den, u32 factor)
+{
+	while (1) {
+		if (((*num)/factor*factor == (*num)) &&
+		   ((*den)/factor*factor == (*den))) {
+			(*num) /= factor;
+			(*den) /= factor;
+		} else
+			break;
+	}
+}
+
+/*
+ * Cancel out the denominator and numerator of a fraction
+ * to get smaller numerator and denominator.
+ */
+void cancel_out(u32 *num, u32 *den, u32 den_limit)
+{
+	do_cancel_out(num, den, 2);
+	do_cancel_out(num, den, 3);
+	do_cancel_out(num, den, 5);
+	do_cancel_out(num, den, 7);
+	do_cancel_out(num, den, 11);
+	do_cancel_out(num, den, 13);
+	do_cancel_out(num, den, 17);
+	while ((*den) > den_limit) {
+		*num /= 2;
+		/*
+		 * Round up the denominator so that the final fraction
+		 * (num/den) is always <= the desired value
+		 */
+		*den = (*den + 1) / 2;
+	}
+}