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/*
* 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/bits.h>
#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/barrier.h>
#include <asm/byteorder.h> /* sigh ... */
#include <asm/compiler.h>
#include <asm/cpu-features.h>
#include <asm/isa-rev.h>
#include <asm/llsc.h>
#include <asm/sgidefs.h>
#include <asm/war.h>
#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_llsc();
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_llsc();
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_llsc();
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 <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__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"
&qu
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