- Initial checkin of the freebios2 tree

git-svn-id: svn://svn.coreboot.org/coreboot/trunk@784 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1

1 files changed, 18 insertions, 0 deletions

diff --git a/src/lib/clog2.c b/src/lib/clog2.c
new file mode 100644
index 0000000000..092b49c821
--- /dev/null
+++ b/src/lib/clog2.c
@@ -0,0 +1,18 @@
+#include <console/console.h>
+
+unsigned long log2(unsigned long x)
+{
+        // assume 8 bits per byte.
+        unsigned long i = 1 << (sizeof(x)*8 - 1);
+        unsigned long pow = sizeof(x) * 8 - 1;
+
+        if (! x) {
+                printk_warning("%s called with invalid parameter of 0\n",
+			__FUNCTION__);
+                return -1;
+        }
+        for(; i > x; i >>= 1, pow--)
+                ;
+
+        return pow;
+}