acrn-hypervisor/hypervisor/include/lib/bits.h

308 lines
8.7 KiB
C

/*-
* Copyright (c) 1998 Doug Rabson
* Copyright (c) 2017 Intel Corporation
* All rights reserved.
*
* 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 BITS_H
#define BITS_H
#include <cpu.h>
/**
*
* INVALID_BIT_INDEX means when input paramter is zero,
* bit operations function can't find bit set and return
* the invalid bit index directly.
*
**/
#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 uint16_t fls32(uint32_t value)
{
uint32_t ret = 0U;
if (value == 0U) {
return (INVALID_BIT_INDEX);
}
asm volatile("bsrl %1,%0"
: "=r" (ret)
: "rm" (value));
return (uint16_t)ret;
}
static inline uint16_t fls64(uint64_t value)
{
uint64_t ret = 0UL;
if (value == 0UL) {
ret = (INVALID_BIT_INDEX);
} else {
asm volatile("bsrq %1,%0"
: "=r" (ret)
: "rm" (value));
}
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 ffs64(uint64_t value)
{
uint64_t ret = 0UL;
if (value == 0UL) {
return (INVALID_BIT_INDEX);
}
asm volatile("bsfq %1,%0"
: "=r" (ret)
: "rm" (value));
return (uint16_t)ret;
}
/*bit scan forward for the least significant bit '0'*/
static inline uint16_t ffz64(uint64_t value)
{
return ffs64(~value);
}
/*
* find the first zero bit in a uint64_t array.
* @pre: the size must be multiple of 64.
*/
static inline uint64_t ffz64_ex(const uint64_t *addr, uint64_t size)
{
uint64_t idx;
for (idx = 0UL; (idx << 6U) < size; idx++) {
if (addr[idx] != ~0UL) {
return (idx << 6U) + ffz64(addr[idx]);
}
}
return size;
}
/**
* Counts leading zeros.
*
* The number of leading zeros is defined as the number of
* most significant bits which are not '1'. E.g.:
* clz(0x80000000)==0
* clz(0x40000000)==1
* ...
* clz(0x00000001)==31
* clz(0x00000000)==32
*
* @param value:The 32 bit value to count the number of leading zeros.
*
* @return The number of leading zeros in 'value'.
*/
static inline uint16_t clz(uint32_t value)
{
if (value == 0U) {
return 32U;
} else {
return (31U - fls32(value));
}
}
/**
* Counts leading zeros (64 bit version).
*
* @param value:The 64 bit value to count the number of leading zeros.
*
* @return The number of leading zeros in 'value'.
*/
static inline uint16_t clz64(uint64_t value)
{
if (value == 0UL) {
return 64U;
} else {
return (63U - fls64(value));
}
}
/*
* (*addr) |= (1UL<<nr);
* Note:Input parameter nr shall be less than 64.
* If nr>=64, it will be truncated.
*/
#define build_bitmap_set(name, op_len, op_type, lock) \
static inline void name(uint16_t nr_arg, volatile op_type *addr) \
{ \
uint16_t nr; \
nr = nr_arg & ((8U * sizeof(op_type)) - 1U); \
asm volatile(lock "or" op_len " %1,%0" \
: "+m" (*addr) \
: "r" ((op_type)(1UL<<nr)) \
: "cc", "memory"); \
}
build_bitmap_set(bitmap_set_nolock, "q", uint64_t, "")
build_bitmap_set(bitmap_set_lock, "q", uint64_t, BUS_LOCK)
build_bitmap_set(bitmap32_set_nolock, "l", uint32_t, "")
build_bitmap_set(bitmap32_set_lock, "l", uint32_t, BUS_LOCK)
/*
* (*addr) &= ~(1UL<<nr);
* Note:Input parameter nr shall be less than 64.
* If nr>=64, it will be truncated.
*/
#define build_bitmap_clear(name, op_len, op_type, lock) \
static inline void name(uint16_t nr_arg, volatile op_type *addr) \
{ \
uint16_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(bitmap_clear_nolock, "q", uint64_t, "")
build_bitmap_clear(bitmap_clear_lock, "q", uint64_t, BUS_LOCK)
build_bitmap_clear(bitmap32_clear_nolock, "l", uint32_t, "")
build_bitmap_clear(bitmap32_clear_lock, "l", uint32_t, BUS_LOCK)
/*
* return !!((*addr) & (1UL<<nr));
* Note:Input parameter nr shall be less than 64. If nr>=64, it will
* be truncated.
*/
static inline bool bitmap_test(uint16_t nr_arg, const volatile uint64_t *addr)
{
uint16_t nr;
int32_t ret = 0;
nr = nr_arg & 0x3fU;
asm volatile("btq %q2,%1\n\tsbbl %0, %0"
: "=r" (ret)
: "m" (*addr), "r" ((uint64_t)nr)
: "cc", "memory");
return (ret != 0);
}
static inline bool bitmap32_test(uint16_t nr_arg, const volatile uint32_t *addr)
{
uint16_t nr;
int32_t ret = 0;
nr = nr_arg & 0x1fU;
asm volatile("btl %2,%1\n\tsbbl %0, %0"
: "=r" (ret)
: "m" (*addr), "r" ((uint32_t)nr)
: "cc", "memory");
return (ret != 0);
}
/*
* bool ret = (*addr) & (1UL<<nr);
* (*addr) |= (1UL<<nr);
* return ret;
* Note:Input parameter nr shall be less than 64. If nr>=64, it
* will be truncated.
*/
#define build_bitmap_testandset(name, op_len, op_type, lock) \
static inline bool name(uint16_t nr_arg, volatile op_type *addr) \
{ \
uint16_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(bitmap_test_and_set_nolock, "q", uint64_t, "")
build_bitmap_testandset(bitmap_test_and_set_lock, "q", uint64_t, BUS_LOCK)
build_bitmap_testandset(bitmap32_test_and_set_nolock, "l", uint32_t, "")
build_bitmap_testandset(bitmap32_test_and_set_lock, "l", uint32_t, BUS_LOCK)
/*
* bool ret = (*addr) & (1UL<<nr);
* (*addr) &= ~(1UL<<nr);
* return ret;
* Note:Input parameter nr shall be less than 64. If nr>=64,
* it will be truncated.
*/
#define build_bitmap_testandclear(name, op_len, op_type, lock) \
static inline bool name(uint16_t nr_arg, volatile op_type *addr) \
{ \
uint16_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(bitmap_test_and_clear_nolock, "q", uint64_t, "")
build_bitmap_testandclear(bitmap_test_and_clear_lock, "q", uint64_t, BUS_LOCK)
build_bitmap_testandclear(bitmap32_test_and_clear_nolock, "l", uint32_t, "")
build_bitmap_testandclear(bitmap32_test_and_clear_lock, "l", uint32_t, BUS_LOCK)
#endif /* BITS_H*/