[src/trunk]: src/sys/external/bsd/drm2/include/linux Add rounddown_pow_of_two.

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/87e34a88adca
branches:  trunk
changeset: 331256:87e34a88adca
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Wed Aug 06 14:05:08 2014 +0000

description:
Add rounddown_pow_of_two.

diffstat:

 sys/external/bsd/drm2/include/linux/log2.h |  10 +++++++++-
 1 files changed, 9 insertions(+), 1 deletions(-)

diffs (24 lines):

diff -r c8d5f33f1ed4 -r 87e34a88adca sys/external/bsd/drm2/include/linux/log2.h
--- a/sys/external/bsd/drm2/include/linux/log2.h        Wed Aug 06 13:57:15 2014 +0000
+++ b/sys/external/bsd/drm2/include/linux/log2.h        Wed Aug 06 14:05:08 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: log2.h,v 1.4 2014/07/16 20:59:58 riastradh Exp $       */
+/*     $NetBSD: log2.h,v 1.5 2014/08/06 14:05:08 riastradh Exp $       */
 
 /*-
  * Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -58,6 +58,14 @@
        return (n + 1);
 }
 
+static inline unsigned long
+rounddown_pow_of_two(unsigned long n)
+{
+
+       /* XXX fls64 is not fls_ulong, but it'll do for now.  */
+       return (1UL << (fls64(n) - 1));
+}
+
 static inline unsigned
 order_base_2(unsigned long n)
 {