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/* SPDX-License-Identifier: GPL-2.0 */
/* atomic.S: These things are too big to do inline.
*
* Copyright (C) 1999, 2007 2012 David S. Miller (davem@davemloft.net)
*/
#include <linux/linkage.h>
#include <asm/asi.h>
#include <asm/backoff.h>
#include <asm/export.h>
.text
/* Three versions of the atomic routines, one that
* does not return a value and does not perform
* memory barriers, and a two which return
* a value, the new and old value resp. and does the
* barriers.
*/
#define ATOMIC_OP(op) \
ENTRY(atomic_##op) /* %o0 = increment, %o1 = atomic_ptr */ \
BACKOFF_SETUP(%o2); \
1: lduw [%o1], %g1; \
op %g1, %o0, %g7; \
cas [%o1], %g1, %g7; \
cmp %g1, %g7; \
bne,pn %icc, BACKOFF_LABEL(2f, 1b); \
nop; \
retl; \
nop; \
2: BACKOFF_SPIN(%o2, %o3, 1b); \
ENDPROC(atomic_##op); \
EXPORT_SYMBOL(atomic_##op);
#define ATOMIC_OP_RETURN(op) \
ENTRY(atomic_##op##_return) /* %o0 = increment, %o1 = atomic_ptr */ \
BACKOFF_SETUP(%o2); \
1: lduw [%o1], %g1; \
op %g1, %o0, %g7; \
cas [%o1], %g1, %g7; \
cmp %g1, %g7; \
bne,pn %icc, BACKOFF_LABEL(2f, 1b); \
op %g1, %o0, %g1; \
retl; \
sra %g1, 0, %o0; \
2: BACKOFF_SPIN(%o2, %o3, 1b); \
ENDPROC(atomic_##op##_return); \
EXPORT_SYMBOL(atomic_##op##_return);
#define ATOMIC_FETCH_OP(op) \
ENTRY(atomic_fetch_##op) /* %o0 = increment, %o1 = atomic_ptr */ \
BACKOFF_SETUP(%o2); \
1: lduw [%o1], %g1; \
op %g1, %o0, %g7; \
cas [%o1], %g1, %g7; \
cmp %g1, %g7; \
bne,pn %icc, BACKOFF_LABEL(2f, 1b); \
nop; \
retl; \
sra %g1, 0, %o0; \
2: BACKOFF_SPIN(%o2, %o3, 1b); \
ENDPROC(atomic_fetch_##op); \
EXPORT_SYMBOL(atomic_fetch_##op);
ATOMIC_OP(add)
ATOMIC_OP_RETURN(add)
ATOMIC_FETCH_OP(add)
ATOMIC_OP(sub)
ATOMIC_OP_RETURN(sub)
ATOMIC_FETCH_OP(sub)
ATOMIC_OP(and)
ATOMIC_FETCH_OP(and)
ATOMIC_OP(or)
ATOMIC_FETCH_OP(or)
ATOMIC_OP(xor)
ATOMIC_FETCH_OP(xor)
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP
#define ATOMIC64_OP(op) \
ENTRY(atomic64_##op) /* %o0 = increment, %o1 = atomic_ptr */ \
BACKOFF_SETUP(%o2); \
1: ldx [%o1], %g1; \
op %g1, %o0, %g7; \
casx [%o1], %g1, %g7; \
cmp %g1, %g7; \
bne,pn %xcc, BACKOFF_LABEL(2f, 1b); \
nop; \
retl; \
nop; \
2: BACKOFF_SPIN(%o2, %o3, 1b); \
ENDPROC(atomic64_##op); \
EXPORT_SYMBOL(atomic64_##op);
#define ATOMIC64_OP_RETURN(op) \
ENTRY(atomic64_##op##_return) /* %o0 = increment, %o1 = atomic_ptr */ \
BACKOFF_SETUP(%o2); \
1: ldx [%o1], %g1; \
op %g1, %o0, %g7; \
casx [%o1], %g1, %g7; \
cmp %g1, %g7; \
bne,pn %xcc, BACKOFF_LABEL(2f, 1b); \
nop; \
retl; \
op %g1, %o0, %o0; \
2: BACKOFF_SPIN(%o2, %o3, 1b); \
ENDPROC(atomic64_##op##_return); \
EXPORT_SYMBOL(atomic64_##op##_return);
#define ATOMIC64_FETCH_OP(op) \
ENTRY(atomic64_fetch_##op) /* %o0 = increment, %o1 = atomic_ptr */ \
BACKOFF_SETUP(%o2); \
1: ldx [%o1], %g1; \
op %g1, %o0, %g7; \
casx [%o1], %g1, %g7; \
cmp %g1, %g7; \
bne,pn %xcc, BACKOFF_LABEL(2f, 1b); \
nop; \
retl; \
mov %g1, %o0; \
2: BACKOFF_SPIN(%o2, %o3, 1b); \
ENDPROC(atomic64_fetch_##op); \
EXPORT_SYMBOL(atomic64_fetch_##op);
ATOMIC64_OP(add)
ATOMIC64_OP_RETURN(add)
ATOMIC64_FETCH_OP(add)
ATOMIC64_OP(sub)
ATOMIC64_OP_RETURN(sub)
ATOMIC64_FETCH_OP(sub)
ATOMIC64_OP(and)
ATOMIC64_FETCH_OP(and)
ATOMIC64_OP(or)
ATOMIC64_FETCH_OP(or)
ATOMIC64_OP(xor)
ATOMIC64_FETCH_OP(xor)
#undef ATOMIC64_FETCH_OP
#undef ATOMIC64_OP_RETURN
#undef ATOMIC64_OP
ENTRY(atomic64_dec_if_positive) /* %o0 = atomic_ptr */
BACKOFF_SETUP(%o2)
1: ldx [%o0], %g1
brlez,pn %g1, 3f
sub %g1, 1, %g7
casx [%o0], %g1, %g7
cmp %g1, %g7
bne,pn %xcc, BACKOFF_LABEL(2f, 1b)
nop
3: retl
sub %g1, 1, %o0
2: BACKOFF_SPIN(%o2, %o3, 1b)
ENDPROC(atomic64_dec_if_positive)
EXPORT_SYMBOL(atomic64_dec_if_positive)