coreboot-libre-fam15h-rdimm/3rdparty/opensbi/lib/sbi/riscv_atomic.c

257 lines
7.9 KiB
C

/*
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2019 Western Digital Corporation or its affiliates.
*
* Authors:
* Anup Patel <anup.patel@wdc.com>
*/
#include <sbi/sbi_types.h>
#include <sbi/riscv_asm.h>
#include <sbi/riscv_atomic.h>
#include <sbi/riscv_barrier.h>
#include <sbi/sbi_bits.h>
long atomic_read(atomic_t *atom)
{
long ret = atom->counter;
rmb();
return ret;
}
void atomic_write(atomic_t *atom, long value)
{
atom->counter = value;
wmb();
}
long atomic_add_return(atomic_t *atom, long value)
{
long ret;
__asm__ __volatile__(" amoadd.w.aqrl %1, %2, %0"
: "+A"(atom->counter), "=r"(ret)
: "r"(value)
: "memory");
return ret + value;
}
long atomic_sub_return(atomic_t *atom, long value)
{
long ret;
__asm__ __volatile__(" amoadd.w.aqrl %1, %2, %0"
: "+A"(atom->counter), "=r"(ret)
: "r"(-value)
: "memory");
return ret - value;
}
#define __axchg(ptr, new, size) \
({ \
__typeof__(ptr) __ptr = (ptr); \
__typeof__(new) __new = (new); \
__typeof__(*(ptr)) __ret; \
switch (size) { \
case 4: \
__asm__ __volatile__ ( \
" amoswap.w.aqrl %0, %2, %1\n" \
: "=r" (__ret), "+A" (*__ptr) \
: "r" (__new) \
: "memory"); \
break; \
case 8: \
__asm__ __volatile__ ( \
" amoswap.d.aqrl %0, %2, %1\n" \
: "=r" (__ret), "+A" (*__ptr) \
: "r" (__new) \
: "memory"); \
break; \
default: \
break; \
} \
__ret; \
})
#define axchg(ptr, x) \
({ \
__typeof__(*(ptr)) _x_ = (x); \
(__typeof__(*(ptr))) __xchg((ptr), _x_, sizeof(*(ptr))); \
})
#define __xchg(ptr, new, size) \
({ \
__typeof__(ptr) __ptr = (ptr); \
__typeof__(*(ptr)) __new = (new); \
__typeof__(*(ptr)) __ret; \
register unsigned int __rc; \
switch (size) { \
case 4: \
__asm__ __volatile__("0: lr.w %0, %2\n" \
" sc.w.rl %1, %z3, %2\n" \
" bnez %1, 0b\n" \
" fence rw, rw\n" \
: "=&r"(__ret), "=&r"(__rc), \
"+A"(*__ptr) \
: "rJ"(__new) \
: "memory"); \
break; \
case 8: \
__asm__ __volatile__("0: lr.d %0, %2\n" \
" sc.d.rl %1, %z3, %2\n" \
" bnez %1, 0b\n" \
" fence rw, rw\n" \
: "=&r"(__ret), "=&r"(__rc), \
"+A"(*__ptr) \
: "rJ"(__new) \
: "memory"); \
break; \
default: \
break; \
} \
__ret; \
})
#define xchg(ptr, n) \
({ \
__typeof__(*(ptr)) _n_ = (n); \
(__typeof__(*(ptr))) __xchg((ptr), _n_, sizeof(*(ptr))); \
})
#define __cmpxchg(ptr, old, new, size) \
({ \
__typeof__(ptr) __ptr = (ptr); \
__typeof__(*(ptr)) __old = (old); \
__typeof__(*(ptr)) __new = (new); \
__typeof__(*(ptr)) __ret; \
register unsigned int __rc; \
switch (size) { \
case 4: \
__asm__ __volatile__("0: lr.w %0, %2\n" \
" bne %0, %z3, 1f\n" \
" sc.w.rl %1, %z4, %2\n" \
" bnez %1, 0b\n" \
" fence rw, rw\n" \
"1:\n" \
: "=&r"(__ret), "=&r"(__rc), \
"+A"(*__ptr) \
: "rJ"(__old), "rJ"(__new) \
: "memory"); \
break; \
case 8: \
__asm__ __volatile__("0: lr.d %0, %2\n" \
" bne %0, %z3, 1f\n" \
" sc.d.rl %1, %z4, %2\n" \
" bnez %1, 0b\n" \
" fence rw, rw\n" \
"1:\n" \
: "=&r"(__ret), "=&r"(__rc), \
"+A"(*__ptr) \
: "rJ"(__old), "rJ"(__new) \
: "memory"); \
break; \
default: \
break; \
} \
__ret; \
})
#define cmpxchg(ptr, o, n) \
({ \
__typeof__(*(ptr)) _o_ = (o); \
__typeof__(*(ptr)) _n_ = (n); \
(__typeof__(*(ptr))) \
__cmpxchg((ptr), _o_, _n_, sizeof(*(ptr))); \
})
long arch_atomic_cmpxchg(atomic_t *atom, long oldval, long newval)
{
#ifdef __riscv_atomic
return __sync_val_compare_and_swap(&atom->counter, oldval, newval);
#else
return cmpxchg(&atom->counter, oldval, newval);
#endif
}
long arch_atomic_xchg(atomic_t *atom, long newval)
{
/* Atomically set new value and return old value. */
#ifdef __riscv_atomic
return axchg(&atom->counter, newval);
#else
return xchg(&atom->counter, newval);
#endif
}
unsigned int atomic_raw_xchg_uint(volatile unsigned int *ptr,
unsigned int newval)
{
/* Atomically set new value and return old value. */
#ifdef __riscv_atomic
return axchg(ptr, newval);
#else
return xchg(ptr, newval);
#endif
}
unsigned long atomic_raw_xchg_ulong(volatile unsigned long *ptr,
unsigned long newval)
{
/* Atomically set new value and return old value. */
#ifdef __riscv_atomic
return axchg(ptr, newval);
#else
return xchg(ptr, newval);
#endif
}
#if (BITS_PER_LONG == 64)
#define __AMO(op) "amo" #op ".d"
#elif (BITS_PER_LONG == 32)
#define __AMO(op) "amo" #op ".w"
#else
#error "Unexpected BITS_PER_LONG"
#endif
#define __atomic_op_bit_ord(op, mod, nr, addr, ord) \
({ \
unsigned long __res, __mask; \
__mask = BIT_MASK(nr); \
__asm__ __volatile__(__AMO(op) #ord " %0, %2, %1" \
: "=r"(__res), "+A"(addr[BIT_WORD(nr)]) \
: "r"(mod(__mask)) \
: "memory"); \
__res; \
})
#define __atomic_op_bit(op, mod, nr, addr) \
__atomic_op_bit_ord(op, mod, nr, addr, .aqrl)
/* Bitmask modifiers */
#define __NOP(x) (x)
#define __NOT(x) (~(x))
inline int atomic_raw_set_bit(int nr, volatile unsigned long *addr)
{
return __atomic_op_bit(or, __NOP, nr, addr);
}
inline int atomic_raw_clear_bit(int nr, volatile unsigned long *addr)
{
return __atomic_op_bit(and, __NOT, nr, addr);
}
inline int atomic_set_bit(int nr, atomic_t *atom)
{
return atomic_raw_set_bit(nr, (unsigned long *)&atom->counter);
}
inline int atomic_clear_bit(int nr, atomic_t *atom)
{
return atomic_raw_clear_bit(nr, (unsigned long *)&atom->counter);
}