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/*
* include/asm-xtensa/bitops.h
*
* Atomic operations that C can't guarantee us.Useful for resource counting etc.
*
* 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) 2001 - 2007 Tensilica Inc.
*/
#ifndef _XTENSA_BITOPS_H
#define _XTENSA_BITOPS_H
#ifndef _LINUX_BITOPS_H
#error only <linux/bitops.h> can be included directly
#endif
#include <asm/processor.h>
#include <asm/byteorder.h>
#include <asm/barrier.h>
#include <asm-generic/bitops/non-atomic.h>
#if XCHAL_HAVE_NSA
static inline unsigned long __cntlz (unsigned long x)
{
int lz;
asm ("nsau %0, %1" : "=r" (lz) : "r" (x));
return lz;
}
/*
* ffz: Find first zero in word. Undefined if no zero exists.
* bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
*/
static inline int ffz(unsigned long x)
{
return 31 - __cntlz(~x & -~x);
}
/*
* __ffs: Find first bit set in word. Return 0 for bit 0
*/
static inline unsigned long __ffs(unsigned long x)
{
return 31 - __cntlz(x & -x);
}
/*
* ffs: Find first bit set in word. 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(unsigned long x)
{
return 32 - __cntlz(x & -x);
}
/*
* fls: Find last (most-significant) bit set in word.
* Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
*/
static inline int fls (unsigned int x)
{
return 32 - __cntlz(x);
}
/**
* __fls - find last (most-significant) set bit in a long word
* @word: the word to search
*
* Undefined if no set bit exists, so code should check against 0 first.
*/
static inline unsigned long __fls(unsigned long word)
{
return 31 - __cntlz(word);
}
#else
/* Use the generic implementation if we don't have the nsa/nsau instructions. */
# include <asm-generic/bitops/ffs.h>
# include <asm-generic/bitops/__ffs.h>
# include <asm-generic/bitops/ffz.h>
# include <asm-generic/bitops/fls.h>
# include <asm-generic/bitops/__fls.h>
#endif
#include <asm-generic/bitops/fls64.h>
#if XCHAL_HAVE_EXCLUSIVE
#define BIT_OP(op, insn, inv) \
static inline void op##_bit(unsigned int bit, volatile unsigned long *p)\
{ \
unsigned long tmp; \
unsigned long mask = 1UL << (bit & 31); \
\
p += bit >> 5; \
\
__asm__ __volatile__( \
"1: l32ex %[tmp], %[addr]\n" \
" "insn" %[tmp], %[tmp], %[mask]\n" \
" s32ex %[tmp], %[addr]\n" \
" getex %[tmp]\n" \
" beqz %[tmp], 1b\n" \
: [tmp] "=&a" (tmp) \
: [mask] "a" (inv mask), [addr] "a" (p) \
: "memory"); \
}
#define TEST_AND_BIT_OP(op, insn, inv) \
static inline int \
test_and_##op##_bit(unsigned int bit, volatile unsigned long *p) \
{ \
unsigned long tmp, value; \
unsigned long mask = 1UL << (bit & 31); \
\
p += bit >> 5; \
\
__asm__ __volatile__( \
"1: l32ex %[value], %[addr]\n" \
" "insn" %[tmp], %[value], %[mask]\n" \
" s32ex %[tmp], %[addr]\n" \
" getex %[tmp]\n" \
" beqz %[tmp], 1b\n" \
: [tmp] "=&a" (tmp), [value] "=&a" (value) \
: [mask] "a" (inv mask), [addr] "a" (p) \
: "memory"); \
\
return value & mask; \
}
#elif XCHAL_HAVE_S32C1I
#define BIT_OP(op, insn, inv) \
static inline void op##_bit(unsigned int bit, volatile unsigned long *p)\
{ \
unsigned long tmp, value; \
unsigned long mask = 1UL << (bit & 31); \
\
p += bit >> 5; \
\
__asm__ __volatile__( \
"1: l32i %[value], %[mem]\n" \
" wsr %[value], scompare1\n" \
" "insn" %[tmp], %[value], %[mask]\n" \
" s32c1i %[tmp], %[mem]\n" \
" bne %[tmp], %[value], 1b\n" \
: [tmp] "=&a" (tmp), [value] "=&a" (value), \
[mem] "+m" (*p) \
: [mask] "a" (inv mask) \
: "memory"); \
}
#define TEST_AND_BIT_OP(op, insn, inv) \
static inline int \
test_and_##op##_bit(unsigned int bit, volatile unsigned long *p) \
{ \
unsigned long tmp, value; \
unsigned long mask = 1UL << (bit & 31); \
\
p += bit >> 5; \
\
__asm__ __volatile__( \
"1: l32i %[value], %[mem]\n" \
" wsr %[value], scompare1\n" \
" "insn" %[tmp], %[value], %[mask]\n" \
" s32c1i %[tmp], %[mem]\n" \
" bne %[tmp], %[value], 1b\n" \
: [tmp] "=&a" (tmp), [value] "=&a" (value), \
[mem] "+m" (*p) \
: [mask] "a" (inv mask) \
: "memory"); \
\
return tmp & mask; \
}
#else
#define BIT_OP(op, insn, inv)
#define TEST_AND_BIT_OP(op, insn, inv)
#include <asm-generic/bitops/atomic.h>
#endif /* XCHAL_HAVE_S32C1I */
#define BIT_OPS(op, insn, inv) \
BIT_OP(op, insn, inv) \
TEST_AND_BIT_OP(op, insn, inv)
BIT_OPS(set, "or", )
BIT_OPS(clear, "and", ~)
BIT_OPS(change, "xor", )
#undef BIT_OPS
#undef BIT_OP
#undef TEST_AND_BIT_OP
#include <asm-generic/bitops/find.h>
#include <asm-generic/bitops/le.h>
#include <asm-generic/bitops/ext2-atomic-setbit.h>
#include <asm-generic/bitops/hweight.h>
#include <asm-generic/bitops/lock.h>
#include <asm-generic/bitops/sched.h>
#endif /* _XTENSA_BITOPS_H */
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