1 #ifndef _NX_BITOPS_H 2 #define _NX_BITOPS_H 3 4 /* 5 * Copyright (C) 2008 Michael Brown <mbrown@fensystems.co.uk>. 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License as 9 * published by the Free Software Foundation; either version 2 of the 10 * License, or any later version. 11 * 12 * This program is distributed in the hope that it will be useful, but 13 * WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 20 */ 21 22 FILE_LICENCE ( GPL2_OR_LATER ); 23 24 /** 25 * @file 26 * 27 * NetXen bit operations 28 * 29 */ 30 31 /** Datatype used to represent a bit in the pseudo-structures */ 32 typedef unsigned char pseudo_bit_t; 33 34 /** 35 * Wrapper structure for pseudo_bit_t structures 36 * 37 * This structure provides a wrapper around pseudo_bit_t structures. 38 * It has the correct size, and also encapsulates type information 39 * about the underlying pseudo_bit_t-based structure, which allows the 40 * NX_FILL etc. macros to work without requiring explicit type 41 * information. 42 */ 43 #define NX_PSEUDO_BIT_STRUCT( _structure ) \ 44 union { \ 45 uint8_t bytes[ sizeof ( _structure ) / 8 ]; \ 46 uint64_t qwords[ sizeof ( _structure ) / 64 ]; \ 47 _structure *dummy[0]; \ 48 } u; 49 50 /** Get pseudo_bit_t structure type from wrapper structure pointer */ 51 #define NX_PSEUDO_STRUCT( _ptr ) \ 52 typeof ( *((_ptr)->u.dummy[0]) ) 53 54 /** Bit offset of a field within a pseudo_bit_t structure */ 55 #define NX_BIT_OFFSET( _ptr, _field ) \ 56 offsetof ( NX_PSEUDO_STRUCT ( _ptr ), _field ) 57 58 /** Bit width of a field within a pseudo_bit_t structure */ 59 #define NX_BIT_WIDTH( _ptr, _field ) \ 60 sizeof ( ( ( NX_PSEUDO_STRUCT ( _ptr ) * ) NULL )->_field ) 61 62 /** Qword offset of a field within a pseudo_bit_t structure */ 63 #define NX_QWORD_OFFSET( _ptr, _field ) \ 64 ( NX_BIT_OFFSET ( _ptr, _field ) / 64 ) 65 66 /** Qword bit offset of a field within a pseudo_bit_t structure 67 * 68 * Yes, using mod-64 would work, but would lose the check for the 69 * error of specifying a mismatched field name and qword index. 70 */ 71 #define NX_QWORD_BIT_OFFSET( _ptr, _index, _field ) \ 72 ( NX_BIT_OFFSET ( _ptr, _field ) - ( 64 * (_index) ) ) 73 74 /** Bit mask for a field within a pseudo_bit_t structure */ 75 #define NX_BIT_MASK( _ptr, _field ) \ 76 ( ( ~( ( uint64_t ) 0 ) ) >> \ 77 ( 64 - NX_BIT_WIDTH ( _ptr, _field ) ) ) 78 79 /* 80 * Assemble native-endian qword from named fields and values 81 * 82 */ 83 84 #define NX_ASSEMBLE_1( _ptr, _index, _field, _value ) \ 85 ( ( ( uint64_t) (_value) ) << \ 86 NX_QWORD_BIT_OFFSET ( _ptr, _index, _field ) ) 87 88 #define NX_ASSEMBLE_2( _ptr, _index, _field, _value, ... ) \ 89 ( NX_ASSEMBLE_1 ( _ptr, _index, _field, _value ) | \ 90 NX_ASSEMBLE_1 ( _ptr, _index, __VA_ARGS__ ) ) 91 92 #define NX_ASSEMBLE_3( _ptr, _index, _field, _value, ... ) \ 93 ( NX_ASSEMBLE_1 ( _ptr, _index, _field, _value ) | \ 94 NX_ASSEMBLE_2 ( _ptr, _index, __VA_ARGS__ ) ) 95 96 #define NX_ASSEMBLE_4( _ptr, _index, _field, _value, ... ) \ 97 ( NX_ASSEMBLE_1 ( _ptr, _index, _field, _value ) | \ 98 NX_ASSEMBLE_3 ( _ptr, _index, __VA_ARGS__ ) ) 99 100 #define NX_ASSEMBLE_5( _ptr, _index, _field, _value, ... ) \ 101 ( NX_ASSEMBLE_1 ( _ptr, _index, _field, _value ) | \ 102 NX_ASSEMBLE_4 ( _ptr, _index, __VA_ARGS__ ) ) 103 104 #define NX_ASSEMBLE_6( _ptr, _index, _field, _value, ... ) \ 105 ( NX_ASSEMBLE_1 ( _ptr, _index, _field, _value ) | \ 106 NX_ASSEMBLE_5 ( _ptr, _index, __VA_ARGS__ ) ) 107 108 #define NX_ASSEMBLE_7( _ptr, _index, _field, _value, ... ) \ 109 ( NX_ASSEMBLE_1 ( _ptr, _index, _field, _value ) | \ 110 NX_ASSEMBLE_6 ( _ptr, _index, __VA_ARGS__ ) ) 111 112 /* 113 * Build native-endian (positive) qword bitmasks from named fields 114 * 115 */ 116 117 #define NX_MASK_1( _ptr, _index, _field ) \ 118 ( NX_BIT_MASK ( _ptr, _field ) << \ 119 NX_QWORD_BIT_OFFSET ( _ptr, _index, _field ) ) 120 121 #define NX_MASK_2( _ptr, _index, _field, ... ) \ 122 ( NX_MASK_1 ( _ptr, _index, _field ) | \ 123 NX_MASK_1 ( _ptr, _index, __VA_ARGS__ ) ) 124 125 #define NX_MASK_3( _ptr, _index, _field, ... ) \ 126 ( NX_MASK_1 ( _ptr, _index, _field ) | \ 127 NX_MASK_2 ( _ptr, _index, __VA_ARGS__ ) ) 128 129 #define NX_MASK_4( _ptr, _index, _field, ... ) \ 130 ( NX_MASK_1 ( _ptr, _index, _field ) | \ 131 NX_MASK_3 ( _ptr, _index, __VA_ARGS__ ) ) 132 133 #define NX_MASK_5( _ptr, _index, _field, ... ) \ 134 ( NX_MASK_1 ( _ptr, _index, _field ) | \ 135 NX_MASK_4 ( _ptr, _index, __VA_ARGS__ ) ) 136 137 #define NX_MASK_6( _ptr, _index, _field, ... ) \ 138 ( NX_MASK_1 ( _ptr, _index, _field ) | \ 139 NX_MASK_5 ( _ptr, _index, __VA_ARGS__ ) ) 140 141 #define NX_MASK_7( _ptr, _index, _field, ... ) \ 142 ( NX_MASK_1 ( _ptr, _index, _field ) | \ 143 NX_MASK_6 ( _ptr, _index, __VA_ARGS__ ) ) 144 145 /* 146 * Populate big-endian qwords from named fields and values 147 * 148 */ 149 150 #define NX_FILL( _ptr, _index, _assembled ) \ 151 do { \ 152 uint64_t *__ptr = &(_ptr)->u.qwords[(_index)]; \ 153 uint64_t __assembled = (_assembled); \ 154 *__ptr = cpu_to_le64 ( __assembled ); \ 155 } while ( 0 ) 156 157 #define NX_FILL_1( _ptr, _index, ... ) \ 158 NX_FILL ( _ptr, _index, NX_ASSEMBLE_1 ( _ptr, _index, __VA_ARGS__ ) ) 159 160 #define NX_FILL_2( _ptr, _index, ... ) \ 161 NX_FILL ( _ptr, _index, NX_ASSEMBLE_2 ( _ptr, _index, __VA_ARGS__ ) ) 162 163 #define NX_FILL_3( _ptr, _index, ... ) \ 164 NX_FILL ( _ptr, _index, NX_ASSEMBLE_3 ( _ptr, _index, __VA_ARGS__ ) ) 165 166 #define NX_FILL_4( _ptr, _index, ... ) \ 167 NX_FILL ( _ptr, _index, NX_ASSEMBLE_4 ( _ptr, _index, __VA_ARGS__ ) ) 168 169 #define NX_FILL_5( _ptr, _index, ... ) \ 170 NX_FILL ( _ptr, _index, NX_ASSEMBLE_5 ( _ptr, _index, __VA_ARGS__ ) ) 171 172 #define NX_FILL_6( _ptr, _index, ... ) \ 173 NX_FILL ( _ptr, _index, NX_ASSEMBLE_6 ( _ptr, _index, __VA_ARGS__ ) ) 174 175 #define NX_FILL_7( _ptr, _index, ... ) \ 176 NX_FILL ( _ptr, _index, NX_ASSEMBLE_7 ( _ptr, _index, __VA_ARGS__ ) ) 177 178 /** Extract value of named field */ 179 #define NX_GET64( _ptr, _field ) \ 180 ( { \ 181 unsigned int __index = NX_QWORD_OFFSET ( _ptr, _field ); \ 182 uint64_t *__ptr = &(_ptr)->u.qwords[__index]; \ 183 uint64_t __value = le64_to_cpu ( *__ptr ); \ 184 __value >>= \ 185 NX_QWORD_BIT_OFFSET ( _ptr, __index, _field ); \ 186 __value &= NX_BIT_MASK ( _ptr, _field ); \ 187 __value; \ 188 } ) 189 190 /** Extract value of named field (for fields up to the size of a long) */ 191 #define NX_GET( _ptr, _field ) \ 192 ( ( unsigned long ) NX_GET64 ( _ptr, _field ) ) 193 194 #endif /* _NX_BITOPS_H */ 195