[PATCH v3 5/5] sparc64: Use sparc optimised fls and __fls for T4 and above

From: Vijay Kumar
Date: Fri Oct 06 2017 - 12:56:08 EST


For T4 and above, patch fls and __fls functions
at the boot time to use lzcnt instruction.

Signed-off-by: Vijay Kumar <vijay.ac.kumar@xxxxxxxxxx>
---
arch/sparc/kernel/head_64.S | 2 ++
arch/sparc/lib/NG4patch.S | 9 +++++++++
2 files changed, 11 insertions(+), 0 deletions(-)

diff --git a/arch/sparc/kernel/head_64.S b/arch/sparc/kernel/head_64.S
index 4de9fbd..f362ecb 100644
--- a/arch/sparc/kernel/head_64.S
+++ b/arch/sparc/kernel/head_64.S
@@ -640,6 +640,8 @@ niagara4_patch:
nop
call niagara4_patch_pageops
nop
+ call niagara4_patch_fls
+ nop

ba,a,pt %xcc, 80f
nop
diff --git a/arch/sparc/lib/NG4patch.S b/arch/sparc/lib/NG4patch.S
index 3cc0f8c..da65a3e 100644
--- a/arch/sparc/lib/NG4patch.S
+++ b/arch/sparc/lib/NG4patch.S
@@ -3,6 +3,8 @@
* Copyright (C) 2012 David S. Miller <davem@xxxxxxxxxxxxx>
*/

+#include <linux/linkage.h>
+
#define BRANCH_ALWAYS 0x10680000
#define NOP 0x01000000
#define NG_DO_PATCH(OLD, NEW) \
@@ -52,3 +54,10 @@ niagara4_patch_pageops:
retl
nop
.size niagara4_patch_pageops,.-niagara4_patch_pageops
+
+ENTRY(niagara4_patch_fls)
+ NG_DO_PATCH(fls, NG4fls)
+ NG_DO_PATCH(__fls, __NG4fls)
+ retl
+ nop
+ENDPROC(niagara4_patch_fls)
--
1.7.1