- 根目录:
- arch
- mips
- include
- asm
- bitops.h
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (c) 1994 - 1997, 99, 2000, 06, 07 Ralf Baechle (ralf@linux-mips.org)
* Copyright (c) 1999, 2000 Silicon Graphics, Inc.
*/
#ifndef _ASM_BITOPS_H
#define _ASM_BITOPS_H
#ifndef _LINUX_BITOPS_H
#error only <linux/bitops.h> can be included directly
#endif
#include <linux/compiler.h>
#include <linux/irqflags.h>
#include <linux/types.h>
#include <asm/barrier.h>
#include <asm/bug.h>
#include <asm/byteorder.h> /* sigh ... */
#include <asm/cpu-features.h>
#include <asm/sgidefs.h>
#include <asm/war.h>
#if _MIPS_SZLONG == 32
#define SZLONG_LOG 5
#define SZLONG_MASK 31UL
#define __LL "ll "
#define __SC "sc "
#define __INS "ins "
#define __EXT "ext "
#elif _MIPS_SZLONG == 64
#define SZLONG_LOG 6
#define SZLONG_MASK 63UL
#define __LL "lld "
#define __SC "scd "
#define __INS "dins "
#define __EXT "dext "
#endif
/*
* clear_bit() doesn't provide any barrier for the compiler.
*/
#define smp_mb__before_clear_bit() smp_mb__before_llsc()
#define smp_mb__after_clear_bit() smp_llsc_mb()
/*
* set_bit - Atomically set a bit in memory
* @nr: the bit to set
* @addr: the address to start counting from
*
* This function is atomic and may not be reordered. See __set_bit()
* if you do not require the atomic guarantees.
* Note that @nr may be almost arbitrarily large; this function is not
* restricted to acting on a single-word quantity.
*/
static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
{
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned short bit = nr & SZLONG_MASK;
unsigned long temp;
if (kernel_uses_llsc && R10000_LLSC_WAR) {
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # set_bit \n"
" or %0, %2 \n"
" " __SC "%0, %1 \n"
" beqzl %0, 1b \n"
" .set mips0 \n"
: "=&r" (temp), "=m" (*m)
: "ir" (1UL << bit), "m" (*m));
#ifdef CONFIG_CPU_MIPSR2
} else if (kernel_uses_llsc && __builtin_constant_p(bit)) {
do {
__asm__ __volatile__(
" " __LL "%0, %1 # set_bit \n"
" " __INS "%0, %3, %2, 1 \n"
" " __SC "%0, %1 \n"
: "=&r" (temp), "+m" (*m)
: "ir" (bit), "r" (~0));
} while (unlikely(!temp));
#endif /* CONFIG_CPU_MIPSR2 */
} else if (kernel_uses_llsc) {
do {
__asm__ __volatile__(
" .set mips3 \n"
" " __LL "%0, %1 # set_bit \n"
" or %0, %2 \n"
" " __SC "%0, %1 \n"
" .set mips0 \n"
: "=&r" (temp), "+m" (*m)
: "ir" (1UL << bit));
} while (unlikely(!temp));
} else {
volatile unsigned long *a = addr;
unsigned long mask;
unsigned long flags;
a += nr >> SZLONG_LOG;
mask = 1UL << bit;
raw_local_irq_save(flags);
*a |= mask;
raw_local_irq_restore(flags);
}
}
/*
* clear_bit - Clears a bit in memory
* @nr: Bit to clear
* @addr: Address to start counting from
*
* clear_bit() is atomic and may not be reordered. However, it does
* not contain a memory barrier, so if it is used for locking purposes,
* you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
* in order to ensure changes are visible on other processors.
*/
static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
{
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned short bit = nr & SZLONG_MASK;
unsigned long temp;
if (kernel_uses_llsc && R10000_LLSC_WAR) {
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # clear_bit \n"
" and %0, %2 \n"
" " __SC "%0, %1 \n"
" beqzl %0, 1b \n"
" .set mips0 \n"
: "=&r" (temp), "+m" (*m)
: "ir" (~(1UL << bit)));
#ifdef CONFIG_CPU_MIPSR2
} else if (kernel_uses_llsc && __builtin_constant_p(bit)) {
do {
__asm__ __volatile__(
" " __LL "%0, %1 # clear_bit \n"
" " __INS "%0, $0, %2, 1 \n"
" " __SC "%0, %1 \n"
: "=&r" (temp), "+m" (*m)
: "ir" (bit));
} while (unlikely(!temp));
#endif /* CONFIG_CPU_MIPSR2 */
} else if (kernel_uses_llsc) {
do {
__asm__ __volatile__(
" .set mips3 \n"
" " __LL "%0, %1 # clear_bit \n"
" and %0, %2 \n"
" " __SC "%0, %1 \n"
" .set mips0 \n"
: "=&r" (temp), "+m" (*m)
: "ir" (~(1UL << bit)));
} while (unlikely(!temp));
} else {
volatile unsigned long *a = addr;
unsigned long mask;
unsigned long flags;
a += nr >> SZLONG_LOG;
mask = 1UL << bit;
raw_local_irq_save(flags);
*a &= ~mask;
raw_local_irq_restore(flags);
}
}
/*
* clear_bit_unlock - Clears a bit in memory
* @nr: Bit to clear
* @addr: Address to start counting from
*
* clear_bit() is atomic and implies release semantics before the memory
* operation. It can be used for an unlock.
*/
static inline void clear_bit_unlock(unsigned long nr, volatile unsigned long *addr)
{
smp_mb__before_clear_bit();
clear_bit(nr, addr);
}
/*
* change_bit - Toggle a bit in memory
* @nr: Bit to change
* @addr: Address to start counting from
*
* change_bit() is atomic and may not be reordered.
* Note that @nr may be almost arbitrarily large; this function is not
* restricted to acting on a single-word quantity.
*/
static inline void change_bit(unsigned long nr, volatile unsigned long *addr)
{
unsigned short bit = nr & SZLONG_MASK;
if (kernel_uses_llsc && R10000_LLSC_WAR) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # change_bit \n"
" xor %0, %2 \n"
" " __SC "%0, %1 \n"
" beqzl %0, 1b \n"
" .set mips0 \n"
: "=&r" (temp), "+m" (*m)
: "ir" (1UL << bit));
} else if (kernel_uses_llsc) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
do {
__asm__ __volatile__(
" .set mips3 \n"
" " __LL "%0, %1 # change_bit \n"
" xor %0, %2 \n"
" " __SC "%0, %1 \n"
" .set mips0 \n"
: "=&r" (temp), "+m" (*m)
: "ir" (1UL << bit));
} while (unlikely(!temp));
} else {
volatile unsigned long *a = addr;
unsigned long mask;
unsigned long flags;
a += nr >> SZLONG_LOG;
mask = 1UL << bit;
raw_local_irq_save(flags);
*a ^= mask;
raw_local_irq_restore(flags);
}
}
/*
* test_and_set_bit - Set a bit and return its old value
* @nr: Bit to set
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
static inline int test_and_set_bit(unsigned long nr,
volatile unsigned long *addr)
{
unsigned short bit = nr & SZLONG_MASK;
unsigned long res;
smp_mb__before_llsc();
if (kernel_uses_llsc && R10000_LLSC_WAR) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # test_and_set_bit \n"
" or %2, %0, %3 \n"
" " __SC "%2, %1 \n"
" beqzl %2, 1b \n"
" and %2, %0, %3 \n"
" .set mips0 \n"
: "=&r" (temp), "+m" (*m), "=&r" (res)
: "r" (1UL << bit)
: "memory");
} else if (kernel_uses_llsc) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
do {
__asm__ __volatile__(
" .set mips3 \n"
" " __LL "%0, %1 # test_and_set_bit \n"
" or %2, %0, %3 \n"
" " __SC "%2, %1 \n"
" .set mips0 \n"
: "=&r" (temp), "+m" (*m), "=&r" (res)
: "r" (1UL << bit)
: "memory");
} while (unlikely(!res));
res = temp & (1UL << bit);
} else {
volatile unsigned long *a = addr;
unsigned long mask;
unsigned long flags;
a += nr >> SZLONG_LOG;
mask = 1UL << bit;
raw_local_irq_save(flags);
res = (mask & *a);
*a |= mask;
raw_local_irq_restore(flags);
}
smp_llsc_mb();
return res != 0;
}
/*
* test_and_set_bit_lock - Set a bit and return its old value
* @nr: Bit to set
* @addr: Address to count from
*
* This operation is atomic and implies acquire ordering semantics
* after the memory operation.
*/
static inline int test_and_set_bit_lock(unsigned long nr,
volatile unsigned long *addr)
{
unsigned short bit = nr & SZLONG_MASK;
unsigned long res;
if (kernel_uses_llsc && R10000_LLSC_WAR) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # test_and_set_bit \n"
" or %2, %0, %3 \n"
" " __SC "%2, %1 \n"
" beqzl %2, 1b \n"
" and %2, %0, %3 \n"
" .set mips0 \n"
: "=&r" (temp), "+m" (*m), "=&r" (res)
: "r" (1UL << bit)
: "memory");
} else if (kernel_uses_llsc) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
do {
__asm__ __volatile__(
" .set mips3 \n"
" " __LL "%0, %1 # test_and_set_bit \n"
" or %2, %0, %3 \n"
" " __SC "%2, %1 \n"
" .set mips0 \n"
: "=&r" (temp), "+m" (*m), "=&r" (res)
: "r" (1UL << bit)
: "memory");
} while (unlikely(!res));
res = temp & (1UL << bit);
} else {
volatile unsigned long *a = addr;
unsigned long mask;
unsigned long flags;
a += nr >> SZLONG_LOG;
mask = 1UL << bit;
raw_local_irq_save(flags);
res = (mask & *a);
*a |= mask;
raw_local_irq_restore(flags);
}
smp_llsc_mb();
return res != 0;
}
/*
* test_and_clear_bit - Clear a bit and return its old value
* @nr: Bit to clear
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
static inline int test_and_clear_bit(unsigned long nr,
volatile unsigned long *addr)
{
unsigned short bit = nr & SZLONG_MASK;
unsigned long res;
smp_mb__before_llsc();
if (kernel_uses_llsc && R10000_LLSC_WAR) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # test_and_clear_bit \n"
" or %2, %0, %3 \n"
" xor %2, %3 \n"
" " __SC "%2, %1 \n"
" beqzl %2, 1b \n"
" and %2, %0, %3 \n"
" .set mips0 \n"
: "=&r" (temp), "+m" (*m), "=&r" (res)
: "r" (1UL << bit)
: "memory");
#ifdef CONFIG_CPU_MIPSR2
} else if (kernel_uses_llsc && __builtin_constant_p(nr)) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
do {
__asm__ __volatile__(
" " __LL "%0, %1 # test_and_clear_bit \n"
" " __EXT "%2, %0, %3, 1 \n"
" " __INS "%0, $0, %3, 1 \n"
" " __SC "%0, %1 \n"
: "=&r" (temp), "+m" (*m), "=&r" (res)
: "ir" (bit)
: "memory");
} while (unlikely(!temp));
#endif
} else if (kernel_uses_llsc) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
do {
__asm__ __volatile__(
" .set mips3 \n"
" " __LL "%0, %1 # test_and_clear_bit \n"
" or %2, %0, %3 \n"
" xor %2, %3 \n"
" " __SC "%2, %1 \n"
" .set mips0 \n"
: "=&r" (temp), "+m" (*m), "=&r" (res)
: "r" (1UL << bit)
: "memory");
} while (unlikely(!res));
res = temp & (1UL << bit);
} else {
volatile unsigned long *a = addr;
unsigned long mask;
unsigned long flags;
a += nr >> SZLONG_LOG;
mask = 1UL << bit;
raw_local_irq_save(flags);
res = (mask & *a);
*a &= ~mask;
raw_local_irq_restore(flags);
}
smp_llsc_mb();
return res != 0;
}
/*
* test_and_change_bit - Change a bit and return its old value
* @nr: Bit to change
* @addr: Address to count from
*
* This operation is atomic and cannot be reordered.
* It also implies a memory barrier.
*/
static inline int test_and_change_bit(unsigned long nr,
volatile unsigned long *addr)
{
unsigned short bit = nr & SZLONG_MASK;
unsigned long res;
smp_mb__before_llsc();
if (kernel_uses_llsc && R10000_LLSC_WAR) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
__asm__ __volatile__(
" .set mips3 \n"
"1: " __LL "%0, %1 # test_and_change_bit \n"
" xor %2, %0, %3 \n"
" " __SC "%2, %1 \n"
" beqzl %2, 1b \n"
" and %2, %0, %3 \n"
" .set mips0 \n"
: "=&r" (temp), "+m" (*m), "=&r" (res)
: "r" (1UL << bit)
: "memory");
} else if (kernel_uses_llsc) {
unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
unsigned long temp;
do {
__asm__ __volatile__(
" .set mips3 \n"
" " __LL "%0, %1 # test_and_change_bit \n"
" xor %2, %0, %3 \n"
" " __SC "\t%2, %1 \n"
" .set mips0 \n"
: "=&r" (temp), "+m" (*m), "=&r" (res)
: "r" (1UL << bit)
: "memory");
} while (unlikely(!res));
res = temp & (1UL << bit);
} else {
volatile unsigned long *a = addr;
unsigned long mask;
unsigned long flags;
a += nr >> SZLONG_LOG;
mask = 1UL << bit;
raw_local_irq_save(flags);
res = (mask & *a);
*a ^= mask;
raw_local_irq_restore(flags);
}
smp_llsc_mb();
return res != 0;
}
#include <asm-generic/bitops/non-atomic.h>
/*
* __clear_bit_unlock - Clears a bit in memory
* @nr: Bit to clear
* @addr: Address to start counting from
*
* __clear_bit() is non-atomic and implies release semantics before the memory
* operation. It can be used for an unlock if no other CPUs can concurrently
* modify other bits in the word.
*/
static inline void __clear_bit_unlock(unsigned long nr, volatile unsigned long *addr)
{
smp_mb();
__clear_bit(nr, addr);
}
/*
* Return the bit position (0..63) of the most significant 1 bit in a word
* Returns -1 if no 1 bit exists
*/
static inline unsigned long __fls(unsigned long word)
{
int num;
if (BITS_PER_LONG == 32 &&
__builtin_constant_p(cpu_has_clo_clz) && cpu_has_clo_clz) {
__asm__(
" .set push \n"
" .set mips32 \n"
" clz %0, %1 \n"
" .set pop \n"
: "=r" (num)
: "r" (word));
return 31 - num;
}
if (BITS_PER_LONG == 64 &&
__builtin_constant_p(cpu_has_mips64) && cpu_has_mips64) {
__asm__(
" .set push \n"
" .set mips64 \n"
" dclz %0, %1 \n"
" .set pop \n"
: "=r" (num)
: "r" (word));
return 63 - num;
}
num = BITS_PER_LONG - 1;
#if BITS_PER_LONG == 64
if (!(word & (~0ul << 32))) {
num -= 32;
word <<= 32;
}
#endif
if (!(word & (~0ul << (BITS_PER_LONG-16)))) {
num -= 16;
word <<= 16;
}
if (!(word & (~0ul << (BITS_PER_LONG-8)))) {
num -= 8;
word <<= 8;
}
if (!(word & (~0ul << (BITS_PER_LONG-4)))) {
num -= 4;
word <<= 4;
}
if (!(word & (~0ul << (BITS_PER_LONG-2)))) {
num -= 2;
word <<= 2;
}
if (!(word & (~0ul << (BITS_PER_LONG-1))))
num -= 1;
return num;
}
/*
* __ffs - find first bit in word.
* @word: The word to search
*
* Returns 0..SZLONG-1
* Undefined if no bit exists, so code should check against 0 first.
*/
static inline unsigned long __ffs(unsigned long word)
{
return __fls(word & -word);
}
/*
* fls - find last bit set.
* @word: The word to search
*
* This is defined the same way as ffs.
* Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
*/
static inline int fls(int x)
{
int r;
if (__builtin_constant_p(cpu_has_clo_clz) && cpu_has_clo_clz) {
__asm__("clz %0, %1" : "=r" (x) : "r" (x));
return 32 - x;
}
r = 32;
if (!x)
return 0;
if (!(x & 0xffff0000u)) {
x <<= 16;
r -= 16;
}
if (!(x & 0xff000000u)) {
x <<= 8;
r -= 8;
}
if (!(x & 0xf0000000u)) {
x <<= 4;
r -= 4;
}
if (!(x & 0xc0000000u)) {
x <<= 2;
r -= 2;
}
if (!(x & 0x80000000u)) {
x <<= 1;
r -= 1;
}
return r;
}
#include <asm-generic/bitops/fls64.h>
/*
* ffs - find first bit set.
* @word: The word to search
*
* This is defined the same way as
* the libc and compiler builtin ffs routines, therefore
* differs in spirit from the above ffz (man ffs).
*/
static inline int ffs(int word)
{
if (!word)
return 0;
return fls(word & -word);
}
#include <asm-generic/bitops/ffz.h>
#include <asm-generic/bitops/find.h>
#ifdef __KERNEL__
#include <asm-generic/bitops/sched.h>
#include <asm/arch_hweight.h>
#include <asm-generic/bitops/const_hweight.h>
#include <asm-generic/bitops/le.h>
#include <asm-generic/bitops/ext2-atomic.h>
#endif /* __KERNEL__ */
#endif /* _ASM_BITOPS_H */