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sparc64: Define SPARC default __fls function

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__fls will now require a boot time patching on T4 and above.
Redefining it under arch/sparc/lib.

Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Vijay Kumar 2017-10-11 12:50:03 -06:00 committed by David S. Miller
parent 41413a6035
commit be52bbe3ea
3 changed files with 63 additions and 1 deletions
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2
arch/sparc/include/asm/bitops_64.h
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@ -23,10 +23,10 @@ void clear_bit(unsigned long nr, volatile unsigned long *addr);
void change_bit(unsigned long nr, volatile unsigned long *addr);
int fls(unsigned int word);
int __fls(unsigned long word);
#include <asm-generic/bitops/non-atomic.h>
#include <asm-generic/bitops/__fls.h>
#include <asm-generic/bitops/fls64.h>
#ifdef __KERNEL__

1
arch/sparc/lib/Makefile
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@ -17,6 +17,7 @@ lib-$(CONFIG_SPARC32) += lshrdi3.o ashldi3.o
lib-$(CONFIG_SPARC32) += muldi3.o bitext.o cmpdi2.o
lib-$(CONFIG_SPARC64) += multi3.o
lib-$(CONFIG_SPARC64) += fls.o
lib-$(CONFIG_SPARC64) += fls64.o
lib-$(CONFIG_SPARC64) += copy_page.o clear_page.o bzero.o
lib-$(CONFIG_SPARC64) += csum_copy.o csum_copy_from_user.o csum_copy_to_user.o

61
arch/sparc/lib/fls64.S Normal file
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@ -0,0 +1,61 @@
/* fls64.S: SPARC default __fls definition.
*
* SPARC default __fls definition, which follows the same algorithm as
* in generic __fls(). This function will be boot time patched on T4
* and onward.
*/
#include <linux/linkage.h>
#include <asm/export.h>
.text
.register %g2, #scratch
.register %g3, #scratch
ENTRY(__fls)
mov -1, %g2
sllx %g2, 32, %g2
and %o0, %g2, %g2
brnz,pt %g2, 1f
mov 63, %g1
sllx %o0, 32, %o0
mov 31, %g1
1:
mov -1, %g2
sllx %g2, 48, %g2
and %o0, %g2, %g2
brnz,pt %g2, 2f
mov -1, %g2
sllx %o0, 16, %o0
add %g1, -16, %g1
2:
mov -1, %g2
sllx %g2, 56, %g2
and %o0, %g2, %g2
brnz,pt %g2, 3f
mov -1, %g2
sllx %o0, 8, %o0
add %g1, -8, %g1
3:
sllx %g2, 60, %g2
and %o0, %g2, %g2
brnz,pt %g2, 4f
mov -1, %g2
sllx %o0, 4, %o0
add %g1, -4, %g1
4:
sllx %g2, 62, %g2
and %o0, %g2, %g2
brnz,pt %g2, 5f
mov -1, %g3
sllx %o0, 2, %o0
add %g1, -2, %g1
5:
mov 0, %g2
sllx %g3, 63, %g3
and %o0, %g3, %o0
movre %o0, 1, %g2
sub %g1, %g2, %g1
jmp %o7+8
sra %g1, 0, %o0
ENDPROC(__fls)
EXPORT_SYMBOL(__fls)