/usr/src/linux-headers-5.15.0-181/arch/mips/include/asm
Edit: /usr/src/linux-headers-5.15.0-181/arch/mips/include/asm/bitops.h (10914B)
/*
* 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
can be included directly
#endif
#include
#include
#include
#include
#include /* sigh ... */
#include
#include
#include
#include
#include
#include
#define __bit_op(mem, insn, inputs...) do { \
unsigned long __temp; \
\
asm volatile( \
" .set push \n" \
" .set " MIPS_ISA_LEVEL " \n" \
" " __SYNC(full, loongson3_war) " \n" \
"1: " __LL "%0, %1 \n" \
" " insn " \n" \
" " __SC "%0, %1 \n" \
" " __SC_BEQZ "%0, 1b \n" \
" .set pop \n" \
: "=&r"(__temp), "+" GCC_OFF_SMALL_ASM()(mem) \
: inputs \
: __LLSC_CLOBBER); \
} while (0)
#define __test_bit_op(mem, ll_dst, insn, inputs...) ({ \
unsigned long __orig, __temp; \
\
asm volatile( \
" .set push \n" \
" .set " MIPS_ISA_LEVEL " \n" \
" " __SYNC(full, loongson3_war) " \n" \
"1: " __LL ll_dst ", %2 \n" \
" " insn " \n" \
" " __SC "%1, %2 \n" \
" " __SC_BEQZ "%1, 1b \n" \
" .set pop \n" \
: "=&r"(__orig), "=&r"(__temp), \
"+" GCC_OFF_SMALL_ASM()(mem) \
: inputs \
: __LLSC_CLOBBER); \
\
__orig; \
})
/*
* These are the "slower" versions of the functions and are in bitops.c.
* These functions call raw_local_irq_{save,restore}().
*/
void __mips_set_bit(unsigned long nr, volatile unsigned long *addr);
void __mips_clear_bit(unsigned long nr, volatile unsigned long *addr);
void __mips_change_bit(unsigned long nr, volatile unsigned long *addr);
int __mips_test_and_set_bit_lock(unsigned long nr,
volatile unsigned long *addr);
int __mips_test_and_clear_bit(unsigned long nr,
volatile unsigned long *addr);
int __mips_test_and_change_bit(unsigned long nr,
volatile unsigned long *addr);
/*
* 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)
{
volatile unsigned long *m = &addr[BIT_WORD(nr)];
int bit = nr % BITS_PER_LONG;
if (!kernel_uses_llsc) {
__mips_set_bit(nr, addr);
return;
}
if ((MIPS_ISA_REV >= 2) && __builtin_constant_p(bit) && (bit >= 16)) {
__bit_op(*m, __INS "%0, %3, %2, 1", "i"(bit), "r"(~0));
return;
}
__bit_op(*m, "or\t%0, %2", "ir"(BIT(bit)));
}
/*
* 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_atomic() and/or smp_mb__after_atomic()
* in order to ensure changes are visible on other processors.
*/
static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
{
volatile unsigned long *m = &addr[BIT_WORD(nr)];
int bit = nr % BITS_PER_LONG;
if (!kernel_uses_llsc) {
__mips_clear_bit(nr, addr);
return;
}
if ((MIPS_ISA_REV >= 2) && __builtin_constant_p(bit)) {
__bit_op(*m, __INS "%0, $0, %2, 1", "i"(bit));
return;
}
__bit_op(*m, "and\t%0, %2", "ir"(~BIT(bit)));
}
/*
* 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_atomic();
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)
{
volatile unsigned long *m = &addr[BIT_WORD(nr)];
int bit = nr % BITS_PER_LONG;
if (!kernel_uses_llsc) {
__mips_change_bit(nr, addr);
return;
}
__bit_op(*m, "xor\t%0, %2", "ir"(BIT(bit)));
}
/*
* 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)
{
volatile unsigned long *m = &addr[BIT_WORD(nr)];
int bit = nr % BITS_PER_LONG;
unsigned long res, orig;
if (!kernel_uses_llsc) {
res = __mips_test_and_set_bit_lock(nr, addr);
} else {
orig = __test_bit_op(*m, "%0",
"or\t%1, %0, %3",
"ir"(BIT(bit)));
res = (orig & BIT(bit)) != 0;
}
smp_llsc_mb();
return res;
}
/*
* 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)
{
smp_mb__before_atomic();
return test_and_set_bit_lock(nr, addr);
}
/*
* 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)
{
volatile unsigned long *m = &addr[BIT_WORD(nr)];
int bit = nr % BITS_PER_LONG;
unsigned long res, orig;
smp_mb__before_atomic();
if (!kernel_uses_llsc) {
res = __mips_test_and_clear_bit(nr, addr);
} else if ((MIPS_ISA_REV >= 2) && __builtin_constant_p(nr)) {
res = __test_bit_op(*m, "%1",
__EXT "%0, %1, %3, 1;"
__INS "%1, $0, %3, 1",
"i"(bit));
} else {
orig = __test_bit_op(*m, "%0",
"or\t%1, %0, %3;"
"xor\t%1, %1, %3",
"ir"(BIT(bit)));
res = (orig & BIT(bit)) != 0;
}
smp_llsc_mb();
return res;
}
/*
* 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)
{
volatile unsigned long *m = &addr[BIT_WORD(nr)];
int bit = nr % BITS_PER_LONG;
unsigned long res, orig;
smp_mb__before_atomic();
if (!kernel_uses_llsc) {
res = __mips_test_and_change_bit(nr, addr);
} else {
orig = __test_bit_op(*m, "%0",
"xor\t%1, %0, %3",
"ir"(BIT(bit)));
res = (orig & BIT(bit)) != 0;
}
smp_llsc_mb();
return res;
}
#undef __bit_op
#undef __test_bit_op
#include
/*
* __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__before_llsc();
__clear_bit(nr, addr);
nudge_writes();
}
/*
* Return the bit position (0..63) of the most significant 1 bit in a word
* Returns -1 if no 1 bit exists
*/
static __always_inline unsigned long __fls(unsigned long word)
{
int num;
if (BITS_PER_LONG == 32 && !__builtin_constant_p(word) &&
__builtin_constant_p(cpu_has_clo_clz) && cpu_has_clo_clz) {
__asm__(
" .set push \n"
" .set "MIPS_ISA_LEVEL" \n"
" clz %0, %1 \n"
" .set pop \n"
: "=r" (num)
: "r" (word));
return 31 - num;
}
if (BITS_PER_LONG == 64 && !__builtin_constant_p(word) &&
__builtin_constant_p(cpu_has_mips64) && cpu_has_mips64) {
__asm__(
" .set push \n"
" .set "MIPS_ISA_LEVEL" \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 __always_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(unsigned int x)
{
int r;
if (!__builtin_constant_p(x) &&
__builtin_constant_p(cpu_has_clo_clz) && cpu_has_clo_clz) {
__asm__(
" .set push \n"
" .set "MIPS_ISA_LEVEL" \n"
" clz %0, %1 \n"
" .set pop \n"
: "=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
/*
* 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 below ffz (man ffs).
*/
static inline int ffs(int word)
{
if (!word)
return 0;
return fls(word & -word);
}
#include
#include
#ifdef __KERNEL__
#include
#include
#include
#include
#include
#endif /* __KERNEL__ */
#endif /* _ASM_BITOPS_H */