1 /* -*- linux-c -*- ------------------------------------------------------- * 2 * 3 * Copyright (C) 1991, 1992 Linus Torvalds 4 * Copyright 2007 rPath, Inc. - All Rights Reserved 5 * 6 * This file is part of the Linux kernel, and is made available under 7 * the terms of the GNU General Public License version 2. 8 * 9 * ----------------------------------------------------------------------- */ 10 11 /* 12 * arch/i386/boot/bitops.h 13 * 14 * Very simple bitops for the boot code. 15 */ 16 17 #ifndef BOOT_BITOPS_H 18 #define BOOT_BITOPS_H 19 #define _LINUX_BITOPS_H /* Inhibit inclusion of <linux/bitops.h> */ 20 21 static inline int constant_test_bit(int nr, const void *addr) 22 { 23 const u32 *p = (const u32 *)addr; 24 return ((1UL << (nr & 31)) & (p[nr >> 5])) != 0; 25 } 26 static inline int variable_test_bit(int nr, const void *addr) 27 { 28 u8 v; 29 const u32 *p = (const u32 *)addr; 30 31 asm("btl %2,%1; setc %0" : "=qm" (v) : "m" (*p), "Ir" (nr)); 32 return v; 33 } 34 35 #define test_bit(nr,addr) \ 36 (__builtin_constant_p(nr) ? \ 37 constant_test_bit((nr),(addr)) : \ 38 variable_test_bit((nr),(addr))) 39 40 static inline void set_bit(int nr, void *addr) 41 { 42 asm("btsl %1,%0" : "+m" (*(u32 *)addr) : "Ir" (nr)); 43 } 44 45 #endif /* BOOT_BITOPS_H */ 46