Viewing file:  barrier.h (3.27 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2020-2022 Loongson Technology Corporation Limited
*/
#ifndef __ASM_BARRIER_H
#define __ASM_BARRIER_H
/*
* Hint encoding:
*
* Bit4: ordering or completion (0: completion, 1: ordering)
* Bit3: barrier for previous read (0: true, 1: false)
* Bit2: barrier for previous write (0: true, 1: false)
* Bit1: barrier for succeeding read (0: true, 1: false)
* Bit0: barrier for succeeding write (0: true, 1: false)
*
* Hint 0x700: barrier for "read after read" from the same address
*/
#define DBAR(hint) __asm__ __volatile__("dbar %0 " : : "I"(hint) : "memory")
#define crwrw 0b00000
#define cr_r_ 0b00101
#define c_w_w 0b01010
#define orwrw 0b10000
#define or_r_ 0b10101
#define o_w_w 0b11010
#define orw_w 0b10010
#define or_rw 0b10100
#define c_sync() DBAR(crwrw)
#define c_rsync() DBAR(cr_r_)
#define c_wsync() DBAR(c_w_w)
#define o_sync() DBAR(orwrw)
#define o_rsync() DBAR(or_r_)
#define o_wsync() DBAR(o_w_w)
#define ldacq_mb() DBAR(or_rw)
#define strel_mb() DBAR(orw_w)
#define mb() c_sync()
#define rmb() c_rsync()
#define wmb() c_wsync()
#define iob() c_sync()
#define wbflush() c_sync()
#define __smp_mb() o_sync()
#define __smp_rmb() o_rsync()
#define __smp_wmb() o_wsync()
#ifdef CONFIG_SMP
#define __WEAK_LLSC_MB " dbar 0x700 \n"
#else
#define __WEAK_LLSC_MB " \n"
#endif
#define __smp_mb__before_atomic() barrier()
#define __smp_mb__after_atomic() barrier()
/**
* array_index_mask_nospec() - generate a ~0 mask when index < size, 0 otherwise
* @index: array element index
* @size: number of elements in array
*
* Returns:
* 0 - (@index < @size)
*/
#define array_index_mask_nospec array_index_mask_nospec
static inline unsigned long array_index_mask_nospec(unsigned long index,
unsigned long size)
{
unsigned long mask;
__asm__ __volatile__(
"sltu %0, %1, %2\n\t"
#if (__SIZEOF_LONG__ == 4)
"sub.w %0, $zero, %0\n\t"
#elif (__SIZEOF_LONG__ == 8)
"sub.d %0, $zero, %0\n\t"
#endif
: "=r" (mask)
: "r" (index), "r" (size)
:);
return mask;
}
#define __smp_load_acquire(p) \
({ \
typeof(*p) ___p1 = READ_ONCE(*p); \
compiletime_assert_atomic_type(*p); \
ldacq_mb(); \
___p1; \
})
#define __smp_store_release(p, v) \
do { \
compiletime_assert_atomic_type(*p); \
strel_mb(); \
WRITE_ONCE(*p, v); \
} while (0)
#define __smp_store_mb(p, v) \
do { \
union { typeof(p) __val; char __c[1]; } __u = \
{ .__val = (__force typeof(p)) (v) }; \
unsigned long __tmp; \
switch (sizeof(p)) { \
case 1: \
*(volatile __u8 *)&p = *(__u8 *)__u.__c; \
__smp_mb(); \
break; \
case 2: \
*(volatile __u16 *)&p = *(__u16 *)__u.__c; \
__smp_mb(); \
break; \
case 4: \
__asm__ __volatile__( \
"amswap_db.w %[tmp], %[val], %[mem] \n" \
: [mem] "+ZB" (*(u32 *)&p), [tmp] "=&r" (__tmp) \
: [val] "r" (*(__u32 *)__u.__c) \
: ); \
break; \
case 8: \
__asm__ __volatile__( \
"amswap_db.d %[tmp], %[val], %[mem] \n" \
: [mem] "+ZB" (*(u64 *)&p), [tmp] "=&r" (__tmp) \
: [val] "r" (*(__u64 *)__u.__c) \
: ); \
break; \
} \
} while (0)
#include <asm-generic/barrier.h>
#endif /* __ASM_BARRIER_H */
|