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authorRizwan Qureshi <rizwan.qureshi@intel.com>2016-09-07 20:11:11 +0530
committerMartin Roth <martinroth@google.com>2016-09-12 19:51:36 +0200
commit8453c4f2fba7ae95ed14137a14575226b24218af (patch)
tree6b1a684c422910bef540077c03b972b4f843810b /src/include
parentb1b44d34e39e52edfe5521d0671d685962529885 (diff)
downloadcoreboot-8453c4f2fba7ae95ed14137a14575226b24218af.tar.xz
cpu/x86: Move fls() and fms() to mtrr.h
Move the funtion to find most significant bit set(fms) and function to find least significant bit set(fls) to a common place. And remove the duplicates. Change-Id: Ia821038b622d93e7f719c18e5ee3e8112de66a53 Signed-off-by: Rizwan Qureshi <rizwan.qureshi@intel.com> Reviewed-on: https://review.coreboot.org/16525 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Diffstat (limited to 'src/include')
-rw-r--r--src/include/cpu/x86/mtrr.h27
1 files changed, 27 insertions, 0 deletions
diff --git a/src/include/cpu/x86/mtrr.h b/src/include/cpu/x86/mtrr.h
index f32bececfd..79f98905b3 100644
--- a/src/include/cpu/x86/mtrr.h
+++ b/src/include/cpu/x86/mtrr.h
@@ -84,6 +84,33 @@ void set_var_mtrr(unsigned reg, unsigned base, unsigned size, unsigned type);
int get_free_var_mtrr(void);
#endif
+#if !defined(__ASSEMBLER__) && !defined(__ROMCC__)
+
+/* fms: find most significant bit set, stolen from Linux Kernel Source. */
+static inline unsigned int fms(unsigned int x)
+{
+ int r;
+
+ __asm__("bsrl %1,%0\n\t"
+ "jnz 1f\n\t"
+ "movl $0,%0\n"
+ "1:" : "=r" (r) : "g" (x));
+ return r;
+}
+
+/* fls: find least significant bit set */
+static inline unsigned int fls(unsigned int x)
+{
+ int r;
+
+ __asm__("bsfl %1,%0\n\t"
+ "jnz 1f\n\t"
+ "movl $32,%0\n"
+ "1:" : "=r" (r) : "g" (x));
+ return r;
+}
+#endif
+
/* Align up to next power of 2, suitable for ROMCC and assembler too.
* Range of result 256kB to 128MB is good enough here.
*/