diff options
author | Eric Biederman <ebiederm@xmission.com> | 2003-04-22 19:02:15 +0000 |
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committer | Eric Biederman <ebiederm@xmission.com> | 2003-04-22 19:02:15 +0000 |
commit | 8ca8d7665d671e10d72b8fcb4d69121d75f7906e (patch) | |
tree | daad2699b4e6b6014bce5a76e82dd9c974801777 /src/lib/clog2.c | |
parent | b138ac83b53da9abf3dc9a87a1cd4b3d3a8150bd (diff) |
- Initial checkin of the freebios2 tree
git-svn-id: svn://svn.coreboot.org/coreboot/trunk@784 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
Diffstat (limited to 'src/lib/clog2.c')
-rw-r--r-- | src/lib/clog2.c | 18 |
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; +} |