/*- * Copyright (c) 1998 Doug Rabson * Copyright (c) 2017-2025 Intel Corporation. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD$ */ #ifndef X86_LIB_BITS_H #define X86_LIB_BITS_H #include #define INVALID_BIT_INDEX 0xffffU /* * * fls32 - Find the Last (most significant) bit Set in value and * return the bit index of that bit. * * Bits are numbered starting at 0,the least significant bit. * A return value of INVALID_BIT_INDEX means return value is * invalid bit index when the input argument was zero. * * Examples: * fls32 (0x0) = INVALID_BIT_INDEX * fls32 (0x01) = 0 * fls32 (0x80) = 7 * ... * fls32 (0x80000001) = 31 * * @param value: 'uint32_t' type value * * @return value: zero-based bit index, INVALID_BIT_INDEX means * when 'value' was zero, bit operations function can't find bit * set and return the invalid bit index directly. * */ static inline int16_t arch_fls32(uint32_t value) { uint32_t ret; asm volatile("bsrl %1,%0\n\t" "jnz 1f\n\t" "mov %2,%0\n" "1:" : "=r" (ret) : "rm" (value), "i" (INVALID_BIT_INDEX)); return (uint16_t)ret; } static inline uint16_t arch_fls64(uint64_t value) { uint64_t ret = 0UL; asm volatile("bsrq %1,%0\n\t" "jnz 1f\n\t" "mov %2,%0\n" "1:" : "=r" (ret) : "rm" (value), "i" (INVALID_BIT_INDEX)); return (uint16_t)ret; } /* * * ffs64 - Find the First (least significant) bit Set in value(Long type) * and return the index of that bit. * * Bits are numbered starting at 0,the least significant bit. * A return value of INVALID_BIT_INDEX means that the return value is the inalid * bit index when the input argument was zero. * * Examples: * ffs64 (0x0) = INVALID_BIT_INDEX * ffs64 (0x01) = 0 * ffs64 (0xf0) = 4 * ffs64 (0xf00) = 8 * ... * ffs64 (0x8000000000000001) = 0 * ffs64 (0xf000000000000000) = 60 * * @param value: 'uint64_t' type value * * @return value: zero-based bit index, INVALID_BIT_INDEX means * when 'value' was zero, bit operations function can't find bit * set and return the invalid bit index directly. * */ static inline uint16_t arch_ffs64(uint64_t value) { uint64_t ret; asm volatile("bsfq %1,%0\n\t" "jnz 1f\n\t" "mov %2,%0\n" "1:" : "=r" (ret) : "rm" (value), "i" (INVALID_BIT_INDEX)); return (uint16_t)ret; } /* * (*addr) |= (1UL<=64, it will be truncated. */ #define build_bitmap_set(name, op_len, op_type, lock) \ static inline void name(uint32_t nr_arg, volatile op_type *addr) \ { \ uint32_t nr; \ nr = nr_arg & ((8U * sizeof(op_type)) - 1U); \ asm volatile(lock "or" op_len " %1,%0" \ : "+m" (*addr) \ : "r" ((op_type)(1UL<=64, it will be truncated. */ #define build_bitmap_clear(name, op_len, op_type, lock) \ static inline void name(uint32_t nr_arg, volatile op_type *addr) \ { \ uint32_t nr; \ nr = nr_arg & ((8U * sizeof(op_type)) - 1U); \ asm volatile(lock "and" op_len " %1,%0" \ : "+m" (*addr) \ : "r" ((op_type)(~(1UL<<(nr)))) \ : "cc", "memory"); \ } build_bitmap_clear(arch_bitmap_clear, "q", uint64_t, BUS_LOCK) build_bitmap_clear(arch_bitmap32_clear, "l", uint32_t, BUS_LOCK) /* * return !!((*addr) & (1UL<=64, it will * be truncated. */ static inline bool arch_bitmap_test(uint32_t nr, const volatile uint64_t *addr) { int32_t ret = 0; asm volatile("btq %q2,%1\n\tsbbl %0, %0" : "=r" (ret) : "m" (*addr), "r" ((uint64_t)(nr & 0x3fU)) : "cc", "memory"); return (ret != 0); } static inline bool arch_bitmap32_test(uint32_t nr, const volatile uint32_t *addr) { int32_t ret = 0; asm volatile("btl %2,%1\n\tsbbl %0, %0" : "=r" (ret) : "m" (*addr), "r" ((uint32_t)(nr & 0x1fU)) : "cc", "memory"); return (ret != 0); } /* * bool ret = (*addr) & (1UL<=64, it * will be truncated. */ #define build_bitmap_testandset(name, op_len, op_type, lock) \ static inline bool name(uint32_t nr_arg, volatile op_type *addr) \ { \ uint32_t nr; \ int32_t ret=0; \ nr = nr_arg & ((8U * sizeof(op_type)) - 1U); \ asm volatile(lock "bts" op_len " %2,%1\n\tsbbl %0,%0" \ : "=r" (ret), "=m" (*addr) \ : "r" ((op_type)nr) \ : "cc", "memory"); \ return (ret != 0); \ } build_bitmap_testandset(arch_bitmap_test_and_set, "q", uint64_t, BUS_LOCK) build_bitmap_testandset(arch_bitmap32_test_and_set, "l", uint32_t, BUS_LOCK) /* * bool ret = (*addr) & (1UL<=64, * it will be truncated. */ #define build_bitmap_testandclear(name, op_len, op_type, lock) \ static inline bool name(uint32_t nr_arg, volatile op_type *addr) \ { \ uint32_t nr; \ int32_t ret=0; \ nr = nr_arg & ((8U * sizeof(op_type)) - 1U); \ asm volatile(lock "btr" op_len " %2,%1\n\tsbbl %0,%0" \ : "=r" (ret), "=m" (*addr) \ : "r" ((op_type)nr) \ : "cc", "memory"); \ return (ret != 0); \ } build_bitmap_testandclear(arch_bitmap_test_and_clear, "q", uint64_t, BUS_LOCK) build_bitmap_testandclear(arch_bitmap32_test_and_clear, "l", uint32_t, BUS_LOCK) #endif /* X86_LIB_BITS_H */