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Release 4.14 arch/arc/include/asm/bitops.h

/*
 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#ifndef _ASM_BITOPS_H

#define _ASM_BITOPS_H

#ifndef _LINUX_BITOPS_H
#error only <linux/bitops.h> can be included directly
#endif

#ifndef __ASSEMBLY__

#include <linux/types.h>
#include <linux/compiler.h>
#include <asm/barrier.h>
#ifndef CONFIG_ARC_HAS_LLSC
#include <asm/smp.h>
#endif

#ifdef CONFIG_ARC_HAS_LLSC

/*
 * Hardware assisted Atomic-R-M-W
 */


#define BIT_OP(op, c_op, asm_op)					\
static inline void op##_bit(unsigned long nr, volatile unsigned long *m)\
{                                                                       \
        unsigned int temp;                                              \
                                                                        \
        m += nr >> 5;                                                   \
                                                                        \
        nr &= 0x1f;                                                     \
                                                                        \
        __asm__ __volatile__(                                           \
        "1:     llock       %0, [%1]            \n"                     \
        "       " #asm_op " %0, %0, %2  \n"                             \
        "       scond       %0, [%1]            \n"                     \
        "       bnz         1b                  \n"                     \
        : "=&r"(temp)	/* Early clobber, to prevent reg reuse */	\
        : "r"(m),	/* Not "m": llock only supports reg direct addr mode */	\
          "ir"(nr)                                                      \
        : "cc");                                                        \
}

/*
 * Semantically:
 *    Test the bit
 *    if clear
 *        set it and return 0 (old value)
 *    else
 *        return 1 (old value).
 *
 * Since ARC lacks a equivalent h/w primitive, the bit is set unconditionally
 * and the old value of bit is returned
 */

#define TEST_N_BIT_OP(op, c_op, asm_op)					\
static inline int test_and_##op##_bit(unsigned long nr, volatile unsigned long *m)\
{                                                                       \
        unsigned long old, temp;                                        \
                                                                        \
        m += nr >> 5;                                                   \
                                                                        \
        nr &= 0x1f;                                                     \
                                                                        \
	/*                                                              \
         * Explicit full memory barrier needed before/after as          \
         * LLOCK/SCOND themselves don't provide any such smenatic       \
         */								\
        smp_mb();                                                       \
                                                                        \
        __asm__ __volatile__(                                           \
        "1:     llock       %0, [%2]    \n"                             \
        "       " #asm_op " %1, %0, %3  \n"                             \
        "       scond       %1, [%2]    \n"                             \
        "       bnz         1b          \n"                             \
        : "=&r"(old), "=&r"(temp)                                       \
        : "r"(m), "ir"(nr)                                              \
        : "cc");                                                        \
                                                                        \
        smp_mb();                                                       \
                                                                        \
        return (old & (1 << nr)) != 0;                                  \
}

#elif !defined(CONFIG_ARC_PLAT_EZNPS)

/*
 * Non hardware assisted Atomic-R-M-W
 * Locking would change to irq-disabling only (UP) and spinlocks (SMP)
 *
 * There's "significant" micro-optimization in writing our own variants of
 * bitops (over generic variants)
 *
 * (1) The generic APIs have "signed" @nr while we have it "unsigned"
 *     This avoids extra code to be generated for pointer arithmatic, since
 *     is "not sure" that index is NOT -ve
 * (2) Utilize the fact that ARCompact bit fidding insn (BSET/BCLR/ASL) etc
 *     only consider bottom 5 bits of @nr, so NO need to mask them off.
 *     (GCC Quirk: however for constant @nr we still need to do the masking
 *             at compile time)
 */


#define BIT_OP(op, c_op, asm_op)					\
static inline void op##_bit(unsigned long nr, volatile unsigned long *m)\
{                                                                       \
        unsigned long temp, flags;                                      \
        m += nr >> 5;                                                   \
                                                                        \
	/*                                                              \
         * spin lock/unlock provide the needed smp_mb() before/after    \
         */								\
        bitops_lock(flags);                                             \
                                                                        \
        temp = *m;                                                      \
        *m = temp c_op (1UL << (nr & 0x1f));                                    \
                                                                        \
        bitops_unlock(flags);                                           \
}


#define TEST_N_BIT_OP(op, c_op, asm_op)					\
static inline int test_and_##op##_bit(unsigned long nr, volatile unsigned long *m)\
{                                                                       \
        unsigned long old, flags;                                       \
        m += nr >> 5;                                                   \
                                                                        \
        bitops_lock(flags);                                             \
                                                                        \
        old = *m;                                                       \
        *m = old c_op (1UL << (nr & 0x1f));                             \
                                                                        \
        bitops_unlock(flags);                                           \
                                                                        \
        return (old & (1UL << (nr & 0x1f))) != 0;                       \
}

#else /* CONFIG_ARC_PLAT_EZNPS */


#define BIT_OP(op, c_op, asm_op)					\
static inline void op##_bit(unsigned long nr, volatile unsigned long *m)\
{                                                                       \
        m += nr >> 5;                                                   \
                                                                        \
        nr = (1UL << (nr & 0x1f));                                      \
        if (asm_op == CTOP_INST_AAND_DI_R2_R2_R3)                       \
                nr = ~nr;                                               \
                                                                        \
        __asm__ __volatile__(                                           \
        "       mov r2, %0\n"                                           \
        "       mov r3, %1\n"                                           \
        "       .word %2\n"                                             \
        :                                                               \
        : "r"(nr), "r"(m), "i"(asm_op)                                  \
        : "r2", "r3", "memory");                                        \
}


#define TEST_N_BIT_OP(op, c_op, asm_op)					\
static inline int test_and_##op##_bit(unsigned long nr, volatile unsigned long *m)\
{                                                                       \
        unsigned long old;                                              \
                                                                        \
        m += nr >> 5;                                                   \
                                                                        \
        nr = old = (1UL << (nr & 0x1f));                                \
        if (asm_op == CTOP_INST_AAND_DI_R2_R2_R3)                       \
                old = ~old;                                             \
                                                                        \
	/* Explicit full memory barrier needed before/after */		\
        smp_mb();                                                       \
                                                                        \
        __asm__ __volatile__(                                           \
        "       mov r2, %0\n"                                           \
        "       mov r3, %1\n"                                           \
        "       .word %2\n"                                             \
        "       mov %0, r2"                                             \
        : "+r"(old)                                                     \
        : "r"(m), "i"(asm_op)                                           \
        : "r2", "r3", "memory");                                        \
                                                                        \
        smp_mb();                                                       \
                                                                        \
        return (old & nr) != 0;                                 \
}

#endif /* CONFIG_ARC_PLAT_EZNPS */

/***************************************
 * Non atomic variants
 **************************************/


#define __BIT_OP(op, c_op, asm_op)					\
static inline void __##op##_bit(unsigned long nr, volatile unsigned long *m)    \
{                                                                       \
        unsigned long temp;                                             \
        m += nr >> 5;                                                   \
                                                                        \
        temp = *m;                                                      \
        *m = temp c_op (1UL << (nr & 0x1f));                            \
}


#define __TEST_N_BIT_OP(op, c_op, asm_op)				\
static inline int __test_and_##op##_bit(unsigned long nr, volatile unsigned long *m)\
{                                                                       \
        unsigned long old;                                              \
        m += nr >> 5;                                                   \
                                                                        \
        old = *m;                                                       \
        *m = old c_op (1UL << (nr & 0x1f));                             \
                                                                        \
        return (old & (1UL << (nr & 0x1f))) != 0;                       \
}


#define BIT_OPS(op, c_op, asm_op)					\
                                                                        \
	/* set_bit(), clear_bit(), change_bit() */			\
	BIT_OP(op, c_op, asm_op)                                        \
                                                                        \
	/* test_and_set_bit(), test_and_clear_bit(), test_and_change_bit() */\
        TEST_N_BIT_OP(op, c_op, asm_op)                                 \
                                                                        \
	/* __set_bit(), __clear_bit(), __change_bit() */		\
        __BIT_OP(op, c_op, asm_op)                                      \
                                                                        \
	/* __test_and_set_bit(), __test_and_clear_bit(), __test_and_change_bit() */\
        __TEST_N_BIT_OP(op, c_op, asm_op)

#ifndef CONFIG_ARC_PLAT_EZNPS
BIT_OPS(set, |, bset)
BIT_OPS(clear, & ~, bclr)
BIT_OPS(change, ^, bxor)
#else
BIT_OPS(set, |, CTOP_INST_AOR_DI_R2_R2_R3)
BIT_OPS(clear, & ~, CTOP_INST_AAND_DI_R2_R2_R3)
BIT_OPS(change, ^, CTOP_INST_AXOR_DI_R2_R2_R3)
#endif

/*
 * This routine doesn't need to be atomic.
 */

static inline int test_bit(unsigned int nr, const volatile unsigned long *addr) { unsigned long mask; addr += nr >> 5; mask = 1UL << (nr & 0x1f); return ((mask & *addr) != 0); }

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Vineet Gupta50100.00%3100.00%
Total50100.00%3100.00%

#ifdef CONFIG_ISA_ARCOMPACT /* * Count the number of zeros, starting from MSB * Helper for fls( ) friends * This is a pure count, so (1-32) or (0-31) doesn't apply * It could be 0 to 32, based on num of 0's in there * clz(0x8000_0000) = 0, clz(0xFFFF_FFFF)=0, clz(0) = 32, clz(1) = 31 */ static inline __attribute__ ((const)) int clz(unsigned int x) { unsigned int res; __asm__ __volatile__( " norm.f %0, %1 \n" " mov.n %0, 0 \n" " add.p %0, %0, 1 \n" : "=r"(res) : "r"(x) : "cc"); return res; }
static inline int constant_fls(int x) { int 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; }

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Vineet Gupta121100.00%1100.00%
Total121100.00%1100.00%

/* * fls = Find Last Set in word * @result: [1-32] * fls(1) = 1, fls(0x80000000) = 32, fls(0) = 0 */ static inline __attribute__ ((const)) int fls(unsigned long x) { if (__builtin_constant_p(x)) return constant_fls(x); return 32 - clz(x); } /* * __fls: Similar to fls, but zero based (0-31) */ static inline __attribute__ ((const)) int __fls(unsigned long x) { if (!x) return 0; else return fls(x) - 1; } /* * ffs = Find First Set in word (LSB to MSB) * @result: [1-32], 0 if all 0's */ #define ffs(x) ({ unsigned long __t = (x); fls(__t & -__t); }) /* * __ffs: Similar to ffs, but zero based (0-31) */ static inline __attribute__ ((const)) int __ffs(unsigned long word) { if (!word) return word; return ffs(word) - 1; } #else /* CONFIG_ISA_ARCV2 */ /* * fls = Find Last Set in word * @result: [1-32] * fls(1) = 1, fls(0x80000000) = 32, fls(0) = 0 */ static inline __attribute__ ((const)) int fls(unsigned long x) { int n; asm volatile( " fls.f %0, %1 \n" /* 0:31; 0(Z) if src 0 */ " add.nz %0, %0, 1 \n" /* 0:31 -> 1:32 */ : "=r"(n) /* Early clobber not needed */ : "r"(x) : "cc"); return n; } /* * __fls: Similar to fls, but zero based (0-31). Also 0 if no bit set */ static inline __attribute__ ((const)) int __fls(unsigned long x) { /* FLS insn has exactly same semantics as the API */ return __builtin_arc_fls(x); } /* * ffs = Find First Set in word (LSB to MSB) * @result: [1-32], 0 if all 0's */ static inline __attribute__ ((const)) int ffs(unsigned long x) { int n; asm volatile( " ffs.f %0, %1 \n" /* 0:31; 31(Z) if src 0 */ " add.nz %0, %0, 1 \n" /* 0:31 -> 1:32 */ " mov.z %0, 0 \n" /* 31(Z)-> 0 */ : "=r"(n) /* Early clobber not needed */ : "r"(x) : "cc"); return n; } /* * __ffs: Similar to ffs, but zero based (0-31) */ static inline __attribute__ ((const)) int __ffs(unsigned long x) { int n; asm volatile( " ffs.f %0, %1 \n" /* 0:31; 31(Z) if src 0 */ " mov.z %0, 0 \n" /* 31(Z)-> 0 */ : "=r"(n) : "r"(x) : "cc"); return n; } #endif /* CONFIG_ISA_ARCOMPACT */ /* * ffz = Find First Zero in word. * @return:[0-31], 32 if all 1's */ #define ffz(x) __ffs(~(x)) #include <asm-generic/bitops/hweight.h> #include <asm-generic/bitops/fls64.h> #include <asm-generic/bitops/sched.h> #include <asm-generic/bitops/lock.h> #include <asm-generic/bitops/find.h> #include <asm-generic/bitops/le.h> #include <asm-generic/bitops/ext2-atomic-setbit.h> #endif /* !__ASSEMBLY__ */ #endif

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Vineet Gupta67190.19%675.00%
Noam Camus709.41%112.50%
Peter Zijlstra30.40%112.50%
Total744100.00%8100.00%
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