src/drivers/net/phantom/nx_bitops.h

   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 */