8ca8d7665d
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@784 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
18 lines
427 B
C
18 lines
427 B
C
#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;
|
|
}
|