1 /*
2 * Copyright (c) 2015, Xilinx Inc. and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7 /*
8 * @file utilities.h
9 * @brief Utility routines for libmetal.
10 */
11
12 #ifndef __METAL_UTILITIES__H__
13 #define __METAL_UTILITIES__H__
14
15 #include <stdint.h>
16 #include <metal/assert.h>
17
18 #ifdef __cplusplus
19 extern "C" {
20 #endif
21
22 /** \defgroup utilities Simple Utilities
23 * @{ */
24
25 /** Marker for unused function arguments/variables. */
26 #define metal_unused(x) do { (x) = (x); } while (0)
27
28 /** Figure out number of elements in an array. */
29 #define metal_dim(x) (sizeof(x) / sizeof(x[0]))
30
31 /** Minimum of two numbers (warning: multiple evaluation!). */
32 #define metal_min(x, y) ((x) < (y) ? (x) : (y))
33
34 /** Maximum of two numbers (warning: multiple evaluation!). */
35 #define metal_max(x, y) ((x) > (y) ? (x) : (y))
36
37 /** Sign of a number [-1, 0, or 1] (warning: multiple evaluation!). */
38 #define metal_sign(x) ((x) < 0 ? -1 : ((x) > 0 ? 1 : 0))
39
40 /** Align 'size' down to a multiple of 'align' (must be a power of two). */
41 #define metal_align_down(size, align) \
42 ((size) & ~((align) - 1))
43
44 /** Align 'size' up to a multiple of 'align' (must be a power of two). */
45 #define metal_align_up(size, align) \
46 metal_align_down((size) + (align) - 1, align)
47
48 /** Divide (and round down). */
49 #define metal_div_round_down(num, den) \
50 ((num) / (den))
51
52 /** Divide (and round up). */
53 #define metal_div_round_up(num, den) \
54 metal_div_round_down((num) + (den) - 1, (den))
55
56 /** Align 'ptr' down to a multiple of 'align' (must be a power of two). */
57 #define metal_ptr_align_down(ptr, align) \
58 (void *)(metal_align_down((uintptr_t)(ptr), (uintptr_t)(align)))
59
60 /** Align 'ptr' up to a multiple of 'align' (must be a power of two). */
61 #define metal_ptr_align_up(ptr, align) \
62 (void *)(metal_align_up((uintptr_t)(ptr), (uintptr_t)(align)))
63
64 /** Compute offset of a field within a structure. */
65 #define metal_offset_of(structure, member) \
66 ((uintptr_t) &(((structure *) 0)->member))
67
68 /** Compute pointer to a structure given a pointer to one of its fields. */
69 #define metal_container_of(ptr, structure, member) \
70 (void *)((uintptr_t)(ptr) - metal_offset_of(structure, member))
71
72 #define METAL_BITS_PER_ULONG (8 * sizeof(unsigned long))
73
74 #define metal_bit(bit) (1UL << (bit))
75
76 #define metal_bitmap_longs(x) metal_div_round_up((x), METAL_BITS_PER_ULONG)
77
metal_bitmap_set_bit(unsigned long * bitmap,int bit)78 static inline void metal_bitmap_set_bit(unsigned long *bitmap, int bit)
79 {
80 bitmap[bit / METAL_BITS_PER_ULONG] |=
81 metal_bit(bit & (METAL_BITS_PER_ULONG - 1));
82 }
83
metal_bitmap_is_bit_set(unsigned long * bitmap,int bit)84 static inline int metal_bitmap_is_bit_set(unsigned long *bitmap, int bit)
85 {
86 return bitmap[bit / METAL_BITS_PER_ULONG] &
87 metal_bit(bit & (METAL_BITS_PER_ULONG - 1));
88 }
89
metal_bitmap_clear_bit(unsigned long * bitmap,int bit)90 static inline void metal_bitmap_clear_bit(unsigned long *bitmap, int bit)
91 {
92 bitmap[bit / METAL_BITS_PER_ULONG] &=
93 ~metal_bit(bit & (METAL_BITS_PER_ULONG - 1));
94 }
95
metal_bitmap_is_bit_clear(unsigned long * bitmap,int bit)96 static inline int metal_bitmap_is_bit_clear(unsigned long *bitmap, int bit)
97 {
98 return !metal_bitmap_is_bit_set(bitmap, bit);
99 }
100
101 static inline unsigned int
metal_bitmap_next_set_bit(unsigned long * bitmap,unsigned int start,unsigned int max)102 metal_bitmap_next_set_bit(unsigned long *bitmap, unsigned int start,
103 unsigned int max)
104 {
105 unsigned int bit;
106 for (bit = start;
107 bit < max && !metal_bitmap_is_bit_set(bitmap, bit);
108 bit ++)
109 ;
110 return bit;
111 }
112
113 #define metal_bitmap_for_each_set_bit(bitmap, bit, max) \
114 for ((bit) = metal_bitmap_next_set_bit((bitmap), 0, (max)); \
115 (bit) < (max); \
116 (bit) = metal_bitmap_next_set_bit((bitmap), (bit), (max)))
117
118 static inline unsigned int
metal_bitmap_next_clear_bit(unsigned long * bitmap,unsigned int start,unsigned int max)119 metal_bitmap_next_clear_bit(unsigned long *bitmap, unsigned int start,
120 unsigned int max)
121 {
122 unsigned int bit;
123 for (bit = start;
124 bit < max && !metal_bitmap_is_bit_clear(bitmap, bit);
125 bit ++)
126 ;
127 return bit;
128 }
129
130 #define metal_bitmap_for_each_clear_bit(bitmap, bit, max) \
131 for ((bit) = metal_bitmap_next_clear_bit((bitmap), 0, (max)); \
132 (bit) < (max); \
133 (bit) = metal_bitmap_next_clear_bit((bitmap), (bit), (max)))
134
metal_log2(unsigned long in)135 static inline unsigned long metal_log2(unsigned long in)
136 {
137 unsigned long result;
138
139 metal_assert((in & (in - 1)) == 0);
140
141 for (result = 0; (1UL << result) < in; result ++)
142 ;
143 return result;
144 }
145
146 /** @} */
147
148 #ifdef __cplusplus
149 }
150 #endif
151
152 #endif /* __METAL_UTILITIES__H__ */
153