1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2020 The FreeBSD Foundation
5 *
6 * This software was developed by Bj��rn Zeeb under sponsorship from
7 * the FreeBSD Foundation.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 *
30 * $FreeBSD$
31 */
32
33#ifndef	_LINUX_BITFIELD_H
34#define	_LINUX_BITFIELD_H
35
36#include <linux/types.h>
37#include <asm/byteorder.h>
38
39/* Use largest possible type. */
40static inline uint64_t ___lsb(uint64_t f) { return (f & -f); }
41static inline uint64_t ___bitmask(uint64_t f) { return (f / ___lsb(f)); }
42
43#define	_uX_get_bits(_n)						\
44	static __inline uint ## _n ## _t				\
45	u ## _n ## _get_bits(uint ## _n ## _t v, uint ## _n ## _t f)	\
46	{								\
47		return ((v & f) / ___lsb(f));				\
48	}
49
50_uX_get_bits(64)
51_uX_get_bits(32)
52_uX_get_bits(16)
53_uX_get_bits(8)
54
55#define	_leX_get_bits(_n)						\
56	static __inline uint ## _n ## _t				\
57	le ## _n ## _get_bits(__le ## _n v, uint ## _n ## _t f)		\
58	{								\
59		return ((le ## _n ## _to_cpu(v) & f) / ___lsb(f));	\
60	}
61
62_leX_get_bits(64)
63_leX_get_bits(32)
64_leX_get_bits(16)
65
66#define	_uX_encode_bits(_n)						\
67	static __inline uint ## _n ## _t				\
68	u ## _n ## _encode_bits(uint ## _n ## _t v, uint ## _n ## _t f)	\
69	{								\
70		return ((v & ___bitmask(f)) * ___lsb(f));		\
71	}
72
73_uX_encode_bits(64)
74_uX_encode_bits(32)
75_uX_encode_bits(16)
76_uX_encode_bits(8)
77
78#define	_leX_encode_bits(_n)						\
79	static __inline uint ## _n ## _t				\
80	le ## _n ## _encode_bits(__le ## _n v, uint ## _n ## _t f)\
81	{								\
82		return (cpu_to_le ## _n((v & ___bitmask(f)) * ___lsb(f))); \
83	}
84
85_leX_encode_bits(64)
86_leX_encode_bits(32)
87_leX_encode_bits(16)
88
89static __inline void
90le32p_replace_bits(uint32_t *p, uint32_t v, uint32_t f)
91{
92
93	*p = (*p & ~(cpu_to_le32(v))) | le32_encode_bits(v, f);
94	return;
95}
96
97#define	__bf_shf(x)	(__builtin_ffsll(x) - 1)
98
99#define	FIELD_PREP(_mask, _value)					\
100	(((typeof(_mask))(_value) << __bf_shf(_mask)) & (_mask))
101
102#define	FIELD_GET(_mask, _value)					\
103	((typeof(_mask))(((_value) & (_mask)) >> __bf_shf(_mask)))
104
105#endif	/* _LINUX_BITFIELD_H */
106