mirror of
https://github.com/riscv-software-src/opensbi.git
synced 2025-08-24 23:41:23 +01:00
88398696c8
Simplify atomic-related bit operations through __atomic intrinsics. Signed-off-by: Xiang W <wxjstz@126.com> Reviewed-by: Anup Patel <anup@brainfault.org>
134 lines
3.1 KiB
C
134 lines
3.1 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_bitops.h>
|
|
#include <sbi/riscv_asm.h>
|
|
#include <sbi/riscv_atomic.h>
|
|
#include <sbi/riscv_barrier.h>
|
|
|
|
#ifndef __riscv_atomic
|
|
#error "opensbi strongly relies on the A extension of RISC-V"
|
|
#endif
|
|
|
|
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;
|
|
#if __SIZEOF_LONG__ == 4
|
|
__asm__ __volatile__(" amoadd.w.aqrl %1, %2, %0"
|
|
: "+A"(atom->counter), "=r"(ret)
|
|
: "r"(value)
|
|
: "memory");
|
|
#elif __SIZEOF_LONG__ == 8
|
|
__asm__ __volatile__(" amoadd.d.aqrl %1, %2, %0"
|
|
: "+A"(atom->counter), "=r"(ret)
|
|
: "r"(value)
|
|
: "memory");
|
|
#endif
|
|
return ret + value;
|
|
}
|
|
|
|
long atomic_sub_return(atomic_t *atom, long value)
|
|
{
|
|
return atomic_add_return(atom, -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))) __axchg((ptr), _x_, sizeof(*(ptr))); \
|
|
})
|
|
|
|
long atomic_cmpxchg(atomic_t *atom, long oldval, long newval)
|
|
{
|
|
return __sync_val_compare_and_swap(&atom->counter, oldval, newval);
|
|
}
|
|
|
|
long atomic_xchg(atomic_t *atom, long newval)
|
|
{
|
|
/* Atomically set new value and return old value. */
|
|
return axchg(&atom->counter, newval);
|
|
}
|
|
|
|
unsigned int atomic_raw_xchg_uint(volatile unsigned int *ptr,
|
|
unsigned int newval)
|
|
{
|
|
/* Atomically set new value and return old value. */
|
|
return axchg(ptr, newval);
|
|
}
|
|
|
|
unsigned long atomic_raw_xchg_ulong(volatile unsigned long *ptr,
|
|
unsigned long newval)
|
|
{
|
|
/* Atomically set new value and return old value. */
|
|
return axchg(ptr, newval);
|
|
}
|
|
|
|
int atomic_raw_set_bit(int nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long res, mask = BIT_MASK(nr);
|
|
res = __atomic_fetch_or(&addr[BIT_WORD(nr)], mask, __ATOMIC_RELAXED);
|
|
return res & mask ? 1 : 0;
|
|
}
|
|
|
|
int atomic_raw_clear_bit(int nr, volatile unsigned long *addr)
|
|
{
|
|
unsigned long res, mask = BIT_MASK(nr);
|
|
res = __atomic_fetch_and(&addr[BIT_WORD(nr)], ~mask, __ATOMIC_RELAXED);
|
|
return res & mask ? 1 : 0;
|
|
}
|
|
|
|
int atomic_set_bit(int nr, atomic_t *atom)
|
|
{
|
|
return atomic_raw_set_bit(nr, (unsigned long *)&atom->counter);
|
|
}
|
|
|
|
int atomic_clear_bit(int nr, atomic_t *atom)
|
|
{
|
|
return atomic_raw_clear_bit(nr, (unsigned long *)&atom->counter);
|
|
}
|