/*      $OpenBSD: atomic.h,v 1.18 2025/07/04 13:22:29 miod Exp $        */

/* Public Domain */

#ifndef _M88K_ATOMIC_H_
#define _M88K_ATOMIC_H_

#if defined(_KERNEL)

#ifdef MULTIPROCESSOR

/* actual implementation is hairy, see atomic.S */
void            atomic_setbits_int(volatile unsigned int *, unsigned int);
void            atomic_clearbits_int(volatile unsigned int *, unsigned int);
unsigned int    atomic_add_int_nv_mp(volatile unsigned int *, unsigned int);
unsigned int    atomic_sub_int_nv_mp(volatile unsigned int *, unsigned int);
unsigned int    atomic_cas_uint_mp(volatile unsigned int *, unsigned int,
                     unsigned int);
unsigned int    atomic_swap_uint_mp(volatile unsigned int *, unsigned int);

#define atomic_add_int_nv       atomic_add_int_nv_mp
#define atomic_sub_int_nv       atomic_sub_int_nv_mp
#define atomic_cas_uint         atomic_cas_uint_mp
#define atomic_swap_uint        atomic_swap_uint_mp

#else

#include <machine/asm_macro.h>
#include <machine/psl.h>

static __inline void
atomic_setbits_int(volatile unsigned int *uip, unsigned int v)
{
        u_int psr;

        psr = get_psr();
        set_psr(psr | PSR_IND);
        *uip |= v;
        set_psr(psr);
}

static __inline void
atomic_clearbits_int(volatile unsigned int *uip, unsigned int v)
{
        u_int psr;

        psr = get_psr();
        set_psr(psr | PSR_IND);
        *uip &= ~v;
        set_psr(psr);
}

static __inline unsigned int
atomic_add_int_nv_sp(volatile unsigned int *uip, unsigned int v)
{
        u_int psr;
        unsigned int nv;

        psr = get_psr();
        set_psr(psr | PSR_IND);
        *uip += v;
        nv = *uip;
        set_psr(psr);

        return nv;
}

static __inline unsigned int
atomic_sub_int_nv_sp(volatile unsigned int *uip, unsigned int v)
{
        u_int psr;
        unsigned int nv;

        psr = get_psr();
        set_psr(psr | PSR_IND);
        *uip -= v;
        nv = *uip;
        set_psr(psr);

        return nv;
}

static inline unsigned int
atomic_cas_uint_sp(volatile unsigned int *p, unsigned int o, unsigned int n)
{
        u_int psr;
        unsigned int ov;

        psr = get_psr();
        set_psr(psr | PSR_IND);
        ov = *p;
        if (ov == o)
                *p = n;
        set_psr(psr);

        return ov;
}

static inline unsigned int
atomic_swap_uint_sp(volatile unsigned int *p, unsigned int v)
{
        u_int psr;
        unsigned int ov;

        psr = get_psr();
        set_psr(psr | PSR_IND);
        ov = *p;
        *p = v;
        set_psr(psr);

        return ov;
}

#define atomic_add_int_nv       atomic_add_int_nv_sp
#define atomic_sub_int_nv       atomic_sub_int_nv_sp
#define atomic_cas_uint         atomic_cas_uint_sp
#define atomic_swap_uint        atomic_swap_uint_sp

#endif  /* MULTIPROCESSOR */

static __inline__ unsigned int
atomic_clear_int(volatile unsigned int *uip)
{
        u_int oldval;

        oldval = 0;
        __asm__ volatile
            ("xmem %0, %2, %%r0" : "+r"(oldval), "+m"(*uip) : "r"(uip));
        return oldval;
}

#define atomic_add_long_nv(p,v) \
        ((unsigned long)atomic_add_int_nv((unsigned int *)p, (unsigned int)v))
#define atomic_sub_long_nv(p,v) \
        ((unsigned long)atomic_sub_int_nv((unsigned int *)p, (unsigned int)v))

#define atomic_cas_ulong(p,o,n) \
        ((unsigned long)atomic_cas_uint((unsigned int *)p, (unsigned int)o, \
         (unsigned int)n))
#define atomic_cas_ptr(p,o,n) \
        ((void *)atomic_cas_uint((void *)p, (unsigned int)o, (unsigned int)n))

#define atomic_swap_ulong(p,o) \
        ((unsigned long)atomic_swap_uint((unsigned int *)p, (unsigned int)o)
#define atomic_swap_ptr(p,o) \
        ((void *)atomic_swap_uint((void *)p, (unsigned int)o))

static inline void
__sync_synchronize(void)
{
        /* flush_pipeline(); */
        __asm__ volatile ("tb1 0, %%r0, 0" ::: "memory");
}

#else /* _KERNEL */

#if !defined(__GNUC__) || (__GNUC__ < 4)

/*
 * Atomic routines are not available to userland, but we need to prevent
 * <sys/atomic.h> from declaring them as inline wrappers of __sync_* functions,
 * which are not available with gcc 3.
 */

#define atomic_cas_uint         UNIMPLEMENTED
#define atomic_cas_ulong        UNIMPLEMENTED
#define atomic_cas_ptr          UNIMPLEMENTED

#define atomic_swap_uint        UNIMPLEMENTED
#define atomic_swap_ulong       UNIMPLEMENTED
#define atomic_swap_ptr         UNIMPLEMENTED

#define atomic_add_int_nv       UNIMPLEMENTED
#define atomic_add_long_nv      UNIMPLEMENTED
#define atomic_add_int          UNIMPLEMENTED
#define atomic_add_long         UNIMPLEMENTED

#define atomic_inc_int          UNIMPLEMENTED
#define atomic_inc_long         UNIMPLEMENTED

#define atomic_sub_int_nv       UNIMPLEMENTED
#define atomic_sub_long_nv      UNIMPLEMENTED
#define atomic_sub_int          UNIMPLEMENTED
#define atomic_sub_long         UNIMPLEMENTED

#define atomic_dec_int          UNIMPLEMENTED
#define atomic_dec_long         UNIMPLEMENTED

#endif  /* gcc < 4 */

/* trap numbers below 128 would cause a privileged instruction fault */
#define __membar() do {                                         \
        __asm volatile("tb1 0, %%r0, 128" ::: "memory");        \
} while (0)

#define membar_enter()          __membar()
#define membar_exit()           __membar()
#define membar_producer()       __membar()
#define membar_consumer()       __membar()
#define membar_sync()           __membar()

#endif /* defined(_KERNEL) */

#endif /* _M88K_ATOMIC_H_ */