-
Notifications
You must be signed in to change notification settings - Fork 0
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Simple bitops for the new x86 setup code.
A simple collection of bitops for the new x86 setup code. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Loading branch information
H. Peter Anvin
authored and
Linus Torvalds
committed
Jul 12, 2007
1 parent
62bd033
commit ad7e906
Showing
1 changed file
with
45 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,45 @@ | ||
/* -*- linux-c -*- ------------------------------------------------------- * | ||
* | ||
* Copyright (C) 1991, 1992 Linus Torvalds | ||
* Copyright 2007 rPath, Inc. - All Rights Reserved | ||
* | ||
* This file is part of the Linux kernel, and is made available under | ||
* the terms of the GNU General Public License version 2. | ||
* | ||
* ----------------------------------------------------------------------- */ | ||
|
||
/* | ||
* arch/i386/boot/bitops.h | ||
* | ||
* 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> */ | ||
|
||
static inline int constant_test_bit(int nr, const void *addr) | ||
{ | ||
const u32 *p = (const u32 *)addr; | ||
return ((1UL << (nr & 31)) & (p[nr >> 5])) != 0; | ||
} | ||
static inline int variable_test_bit(int nr, const void *addr) | ||
{ | ||
u8 v; | ||
const u32 *p = (const u32 *)addr; | ||
|
||
asm("btl %2,%1; setc %0" : "=qm" (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 */ |