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Our extended ISA provided with optimized solution for all 32bit operations we see in these three headers. Signed-off-by: Noam Camus --- arch/arc/include/asm/atomic.h | 79 +++++++++++++++++++++++++++++++++++- arch/arc/include/asm/bitops.h | 54 +++++++++++++++++++++++++ arch/arc/include/asm/cmpxchg.h | 87 +++++++++++++++++++++++++++++++++------- 3 files changed, 202 insertions(+), 18 deletions(-) diff --git a/arch/arc/include/asm/atomic.h b/arch/arc/include/asm/atomic.h index 7730d30..a626996 100644 --- a/arch/arc/include/asm/atomic.h +++ b/arch/arc/include/asm/atomic.h @@ -17,6 +17,7 @@ #include #include +#ifndef CONFIG_ARC_PLAT_EZNPS #define atomic_read(v) READ_ONCE((v)->counter) #ifdef CONFIG_ARC_HAS_LLSC @@ -180,12 +181,84 @@ ATOMIC_OP(andnot, &= ~, bic) ATOMIC_OP(or, |=, or) ATOMIC_OP(xor, ^=, xor) -#undef ATOMIC_OPS -#undef ATOMIC_OP_RETURN -#undef ATOMIC_OP #undef SCOND_FAIL_RETRY_VAR_DEF #undef SCOND_FAIL_RETRY_ASM #undef SCOND_FAIL_RETRY_VARS +#else /* CONFIG_ARC_PLAT_EZNPS */ +static inline int atomic_read(const atomic_t *v) +{ + int temp; + + __asm__ __volatile__( + " ld.di %0, [%1]" + : "=r"(temp) + : "r"(&v->counter) + : "memory"); + return temp; +} + +static inline void atomic_set(atomic_t *v, int i) +{ + __asm__ __volatile__( + " st.di %0,[%1]" + : + : "r"(i), "r"(&v->counter) + : "memory"); +} + +#define ATOMIC_OP(op, c_op, asm_op) \ +static inline void atomic_##op(int i, atomic_t *v) \ +{ \ + __asm__ __volatile__( \ + " mov r2, %0\n" \ + " mov r3, %1\n" \ + " .word %2\n" \ + : \ + : "r"(i), "r"(&v->counter), "i"(asm_op) \ + : "r2", "r3", "memory"); \ +} \ + +#define ATOMIC_OP_RETURN(op, c_op, asm_op) \ +static inline int atomic_##op##_return(int i, atomic_t *v) \ +{ \ + unsigned int temp = i; \ + \ + /* Explicit full memory barrier needed before/after */ \ + smp_mb(); \ + \ + __asm__ __volatile__( \ + " mov r2, %0\n" \ + " mov r3, %1\n" \ + " .word %2\n" \ + " mov %0, r2" \ + : "+r"(temp) \ + : "r"(&v->counter), "i"(asm_op) \ + : "r2", "r3", "memory"); \ + \ + smp_mb(); \ + \ + temp c_op i; \ + \ + return temp; \ +} + +#define ATOMIC_OPS(op, c_op, asm_op) \ + ATOMIC_OP(op, c_op, asm_op) \ + ATOMIC_OP_RETURN(op, c_op, asm_op) + +ATOMIC_OPS(add, +=, CTOP_INST_AADD_DI_R2_R2_R3) +#define atomic_sub(i, v) atomic_add(-(i), (v)) +#define atomic_sub_return(i, v) atomic_add_return(-(i), (v)) + +ATOMIC_OP(and, &=, CTOP_INST_AAND_DI_R2_R2_R3) +#define atomic_andnot(mask, v) atomic_and(~(mask), (v)) +ATOMIC_OP(or, |=, CTOP_INST_AOR_DI_R2_R2_R3) +ATOMIC_OP(xor, ^=, CTOP_INST_AXOR_DI_R2_R2_R3) +#endif /* CONFIG_ARC_PLAT_EZNPS */ + +#undef ATOMIC_OPS +#undef ATOMIC_OP_RETURN +#undef ATOMIC_OP /** * __atomic_add_unless - add unless the number is a given value diff --git a/arch/arc/include/asm/bitops.h b/arch/arc/include/asm/bitops.h index 57c1f33..5a29185 100644 --- a/arch/arc/include/asm/bitops.h +++ b/arch/arc/include/asm/bitops.h @@ -22,6 +22,7 @@ #include #endif +#ifndef CONFIG_ARC_PLAT_EZNPS #if defined(CONFIG_ARC_HAS_LLSC) /* @@ -155,6 +156,53 @@ static inline int test_and_##op##_bit(unsigned long nr, volatile unsigned long * } #endif /* CONFIG_ARC_HAS_LLSC */ +#else /* CONFIG_ARC_PLAT_EZNPS */ +#define BIT_OP(op, c_op, asm_op) \ +static inline void op##_bit(unsigned long nr, volatile unsigned long *m)\ +{ \ + m += nr >> 5; \ + \ + nr = (1UL << (nr & 0x1f)); \ + if (asm_op == CTOP_INST_AAND_DI_R2_R2_R3) \ + nr = ~nr; \ + \ + __asm__ __volatile__( \ + " mov r2, %0\n" \ + " mov r3, %1\n" \ + " .word %2\n" \ + : \ + : "r"(nr), "r"(m), "i"(asm_op) \ + : "r2", "r3", "memory"); \ +} + +#define TEST_N_BIT_OP(op, c_op, asm_op) \ +static inline int test_and_##op##_bit(unsigned long nr, volatile unsigned long *m)\ +{ \ + unsigned long old; \ + \ + m += nr >> 5; \ + \ + nr = old = (1UL << (nr & 0x1f)); \ + if (asm_op == CTOP_INST_AAND_DI_R2_R2_R3) \ + old = ~old; \ + \ + /* Explicit full memory barrier needed before/after */ \ + smp_mb(); \ + \ + __asm__ __volatile__( \ + " mov r2, %0\n" \ + " mov r3, %1\n" \ + " .word %2\n" \ + " mov %0, r2" \ + : "+r"(old) \ + : "r"(m), "i"(asm_op) \ + : "r2", "r3", "memory"); \ + \ + smp_mb(); \ + \ + return (old & nr) != 0; \ +} +#endif /* CONFIG_ARC_PLAT_EZNPS */ /*************************************** * Non atomic variants @@ -196,9 +244,15 @@ static inline int __test_and_##op##_bit(unsigned long nr, volatile unsigned long /* __test_and_set_bit(), __test_and_clear_bit(), __test_and_change_bit() */\ __TEST_N_BIT_OP(op, c_op, asm_op) +#ifndef CONFIG_ARC_PLAT_EZNPS BIT_OPS(set, |, bset) BIT_OPS(clear, & ~, bclr) BIT_OPS(change, ^, bxor) +#else +BIT_OPS(set, |, CTOP_INST_AOR_DI_R2_R2_R3) +BIT_OPS(clear, & ~, CTOP_INST_AAND_DI_R2_R2_R3) +BIT_OPS(change, ^, CTOP_INST_AXOR_DI_R2_R2_R3) +#endif /* * This routine doesn't need to be atomic. diff --git a/arch/arc/include/asm/cmpxchg.h b/arch/arc/include/asm/cmpxchg.h index af7a2db..6d320d3 100644 --- a/arch/arc/include/asm/cmpxchg.h +++ b/arch/arc/include/asm/cmpxchg.h @@ -14,6 +14,7 @@ #include #include +#ifndef CONFIG_ARC_PLAT_EZNPS #ifdef CONFIG_ARC_HAS_LLSC static inline unsigned long @@ -66,21 +67,6 @@ __cmpxchg(volatile void *ptr, unsigned long expected, unsigned long new) #endif /* CONFIG_ARC_HAS_LLSC */ -#define cmpxchg(ptr, o, n) ((typeof(*(ptr)))__cmpxchg((ptr), \ - (unsigned long)(o), (unsigned long)(n))) - -/* - * Since not supported natively, ARC cmpxchg() uses atomic_ops_lock (UP/SMP) - * just to gaurantee semantics. - * atomic_cmpxchg() needs to use the same locks as it's other atomic siblings - * which also happens to be atomic_ops_lock. - * - * Thus despite semantically being different, implementation of atomic_cmpxchg() - * is same as cmpxchg(). - */ -#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n))) - - /* * xchg (reg with memory) based on "Native atomic" EX insn */ @@ -143,6 +129,63 @@ static inline unsigned long __xchg(unsigned long val, volatile void *ptr, #endif +#else /* CONFIG_ARC_PLAT_EZNPS */ +static inline unsigned long +__cmpxchg(volatile void *ptr, unsigned long expected, unsigned long new) +{ + /* + * Explicit full memory barrier needed before/after + */ + smp_mb(); + + write_aux_reg(CTOP_AUX_GPA1, expected); + + __asm__ __volatile__( + " mov r2, %0\n" + " mov r3, %1\n" + " .word %2\n" + " mov %0, r2" + : "+r"(new) + : "r"(ptr), "i"(CTOP_INST_EXC_DI_R2_R2_R3) + : "r2", "r3", "memory"); + + smp_mb(); + + return new; +} + +static inline unsigned long __xchg(unsigned long val, volatile void *ptr, + int size) +{ + extern unsigned long __xchg_bad_pointer(void); + + switch (size) { + case 4: + /* + * Explicit full memory barrier needed before/after + */ + smp_mb(); + + __asm__ __volatile__( + " mov r2, %0\n" + " mov r3, %1\n" + " .word %2\n" + " mov %0, r2\n" + : "+r"(val) + : "r"(ptr), "i"(CTOP_INST_XEX_DI_R2_R2_R3) + : "r2", "r3", "memory"); + + smp_mb(); + + return val; + } + return __xchg_bad_pointer(); +} + +#define xchg(ptr, with) ((typeof(*(ptr)))__xchg((unsigned long)(with), (ptr), \ + sizeof(*(ptr)))) +#endif /* CONFIG_ARC_PLAT_EZNPS */ + /* * "atomic" variant of xchg() * REQ: It needs to follow the same serialization rules as other atomic_xxx() @@ -158,4 +201,18 @@ static inline unsigned long __xchg(unsigned long val, volatile void *ptr, */ #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) +#define cmpxchg(ptr, o, n) ((typeof(*(ptr)))__cmpxchg((ptr), \ + (unsigned long)(o), (unsigned long)(n))) + +/* + * Since not supported natively, ARC cmpxchg() uses atomic_ops_lock (UP/SMP) + * just to gaurantee semantics. + * atomic_cmpxchg() needs to use the same locks as it's other atomic siblings + * which also happens to be atomic_ops_lock. + * + * Thus despite semantically being different, implementation of atomic_cmpxchg() + * is same as cmpxchg(). + */ +#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n))) + #endif