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authorLinus Torvalds <torvalds@linux-foundation.org>2011-08-05 06:42:36 -1000
committerLinus Torvalds <torvalds@linux-foundation.org>2011-08-05 06:42:36 -1000
commit8cd290a07d095f3b354e3448bcd7757393c29cd5 (patch)
treeaf33cb7677646bc506f1fae34676834dc45584a4 /arch/sparc/lib/ffs.S
parent07d952dc669bb70a9716a81e140e89b7d4969f09 (diff)
parent961f65fc41cdc1f9099a6075258816c0db98e390 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc: sparc: Size mondo queues more sanely. sparc: Access kernel TSB using physical addressing when possible. sparc: Fix __atomic_add_unless() return value. sparc: use kbuild-generic support for true asm-generic header files sparc: Use popc when possible for ffs/__ffs/ffz. sparc: Set reboot-cmd using reboot data hypervisor call if available. sparc: Add some missing hypervisor API groups. sparc: Use hweight64() in popc emulation. sparc: Use popc if possible for hweight routines. sparc: Minor tweaks to Niagara page copy/clear. sparc: Sanitize cpu feature detection and reporting.
Diffstat (limited to 'arch/sparc/lib/ffs.S')
-rw-r--r--arch/sparc/lib/ffs.S84
1 files changed, 84 insertions, 0 deletions
diff --git a/arch/sparc/lib/ffs.S b/arch/sparc/lib/ffs.S
new file mode 100644
index 00000000000..b39389f6989
--- /dev/null
+++ b/arch/sparc/lib/ffs.S
@@ -0,0 +1,84 @@
+#include <linux/linkage.h>
+
+ .register %g2,#scratch
+
+ .text
+ .align 32
+
+ENTRY(ffs)
+ brnz,pt %o0, 1f
+ mov 1, %o1
+ retl
+ clr %o0
+ nop
+ nop
+ENTRY(__ffs)
+ sllx %o0, 32, %g1 /* 1 */
+ srlx %o0, 32, %g2
+
+ clr %o1 /* 2 */
+ movrz %g1, %g2, %o0
+
+ movrz %g1, 32, %o1 /* 3 */
+1: clr %o2
+
+ sllx %o0, (64 - 16), %g1 /* 4 */
+ srlx %o0, 16, %g2
+
+ movrz %g1, %g2, %o0 /* 5 */
+ clr %o3
+
+ movrz %g1, 16, %o2 /* 6 */
+ clr %o4
+
+ and %o0, 0xff, %g1 /* 7 */
+ srlx %o0, 8, %g2
+
+ movrz %g1, %g2, %o0 /* 8 */
+ clr %o5
+
+ movrz %g1, 8, %o3 /* 9 */
+ add %o2, %o1, %o2
+
+ and %o0, 0xf, %g1 /* 10 */
+ srlx %o0, 4, %g2
+
+ movrz %g1, %g2, %o0 /* 11 */
+ add %o2, %o3, %o2
+
+ movrz %g1, 4, %o4 /* 12 */
+
+ and %o0, 0x3, %g1 /* 13 */
+ srlx %o0, 2, %g2
+
+ movrz %g1, %g2, %o0 /* 14 */
+ add %o2, %o4, %o2
+
+ movrz %g1, 2, %o5 /* 15 */
+
+ and %o0, 0x1, %g1 /* 16 */
+
+ add %o2, %o5, %o2 /* 17 */
+ xor %g1, 0x1, %g1
+
+ retl /* 18 */
+ add %o2, %g1, %o0
+ENDPROC(ffs)
+ENDPROC(__ffs)
+
+ .section .popc_6insn_patch, "ax"
+ .word ffs
+ brz,pn %o0, 98f
+ neg %o0, %g1
+ xnor %o0, %g1, %o1
+ popc %o1, %o0
+98: retl
+ nop
+ .word __ffs
+ neg %o0, %g1
+ xnor %o0, %g1, %o1
+ popc %o1, %o0
+ retl
+ sub %o0, 1, %o0
+ nop
+ .previous