kernel/arch/x86/boot/bitops.h
2024-07-22 17:22:30 +08:00

45 lines
1.1 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/* -*- linux-c -*- ------------------------------------------------------- *
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright 2007 rPath, Inc. - All Rights Reserved
*
* ----------------------------------------------------------------------- */
/*
* Very simple bitops for the boot code.
*/
#ifndef BOOT_BITOPS_H
#define BOOT_BITOPS_H
#define _LINUX_BITOPS_H /* Inhibit inclusion of <linux/bitops.h> */
#include <linux/types.h>
#include <asm/asm.h>
static inline bool constant_test_bit(int nr, const void *addr)
{
const u32 *p = (const u32 *)addr;
return ((1UL << (nr & 31)) & (p[nr >> 5])) != 0;
}
static inline bool variable_test_bit(int nr, const void *addr)
{
bool v;
const u32 *p = (const u32 *)addr;
asm("btl %2,%1" CC_SET(c) : CC_OUT(c) (v) : "m" (*p), "Ir" (nr));
return v;
}
#define test_bit(nr,addr) \
(__builtin_constant_p(nr) ? \
constant_test_bit((nr),(addr)) : \
variable_test_bit((nr),(addr)))
static inline void set_bit(int nr, void *addr)
{
asm("btsl %1,%0" : "+m" (*(u32 *)addr) : "Ir" (nr));
}
#endif /* BOOT_BITOPS_H */