| #ifndef _GPXE_BITOPS_H |
| #define _GPXE_BITOPS_H |
| |
| /* |
| * Copyright (C) 2008 Michael Brown <mbrown@fensystems.co.uk>. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License as |
| * published by the Free Software Foundation; either version 2 of the |
| * License, or any later version. |
| * |
| * This program is distributed in the hope that it will be useful, but |
| * WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| */ |
| |
| FILE_LICENCE ( GPL2_OR_LATER ); |
| |
| /** |
| * @file |
| * |
| * Bit operations |
| * |
| */ |
| |
| #include <stdint.h> |
| #include <byteswap.h> |
| |
| /* Endianness selection. |
| * |
| * This is a property of the NIC, not a property of the host CPU. |
| */ |
| #ifdef BITOPS_LITTLE_ENDIAN |
| #define cpu_to_BIT64 cpu_to_le64 |
| #define cpu_to_BIT32 cpu_to_le32 |
| #define BIT64_to_cpu le64_to_cpu |
| #define BIT32_to_cpu le32_to_cpu |
| #endif |
| #ifdef BITOPS_BIG_ENDIAN |
| #define cpu_to_BIT64 cpu_to_be64 |
| #define cpu_to_BIT32 cpu_to_be32 |
| #define BIT64_to_cpu be64_to_cpu |
| #define BIT32_to_cpu be32_to_cpu |
| #endif |
| |
| /** Datatype used to represent a bit in the pseudo-structures */ |
| typedef unsigned char pseudo_bit_t; |
| |
| /** |
| * Wrapper structure for pseudo_bit_t structures |
| * |
| * This structure provides a wrapper around pseudo_bit_t structures. |
| * It has the correct size, and also encapsulates type information |
| * about the underlying pseudo_bit_t-based structure, which allows the |
| * BIT_FILL() etc. macros to work without requiring explicit type |
| * information. |
| */ |
| #define PSEUDO_BIT_STRUCT( _structure ) \ |
| union { \ |
| uint8_t bytes[ sizeof ( _structure ) / 8 ]; \ |
| uint32_t dwords[ sizeof ( _structure ) / 32 ]; \ |
| uint64_t qwords[ sizeof ( _structure ) / 64 ]; \ |
| _structure *dummy[0]; \ |
| } u |
| |
| /** Get pseudo_bit_t structure type from wrapper structure pointer */ |
| #define PSEUDO_BIT_STRUCT_TYPE( _ptr ) \ |
| typeof ( *((_ptr)->u.dummy[0]) ) |
| |
| /** Bit offset of a field within a pseudo_bit_t structure */ |
| #define BIT_OFFSET( _ptr, _field ) \ |
| offsetof ( PSEUDO_BIT_STRUCT_TYPE ( _ptr ), _field ) |
| |
| /** Bit width of a field within a pseudo_bit_t structure */ |
| #define BIT_WIDTH( _ptr, _field ) \ |
| sizeof ( ( ( PSEUDO_BIT_STRUCT_TYPE ( _ptr ) * ) NULL )->_field ) |
| |
| /** Qword offset of a field within a pseudo_bit_t structure */ |
| #define QWORD_OFFSET( _ptr, _field ) \ |
| ( BIT_OFFSET ( _ptr, _field ) / 64 ) |
| |
| /** Qword bit offset of a field within a pseudo_bit_t structure */ |
| #define QWORD_BIT_OFFSET( _ptr, _index, _field ) \ |
| ( BIT_OFFSET ( _ptr, _field ) - ( 64 * (_index) ) ) |
| |
| /** Bit mask for a field within a pseudo_bit_t structure */ |
| #define BIT_MASK( _ptr, _field ) \ |
| ( ( ~( ( uint64_t ) 0 ) ) >> \ |
| ( 64 - BIT_WIDTH ( _ptr, _field ) ) ) |
| |
| /* |
| * Assemble native-endian qword from named fields and values |
| * |
| */ |
| |
| #define BIT_ASSEMBLE_1( _ptr, _index, _field, _value ) \ |
| ( ( ( uint64_t) (_value) ) << \ |
| QWORD_BIT_OFFSET ( _ptr, _index, _field ) ) |
| |
| #define BIT_ASSEMBLE_2( _ptr, _index, _field, _value, ... ) \ |
| ( BIT_ASSEMBLE_1 ( _ptr, _index, _field, _value ) | \ |
| BIT_ASSEMBLE_1 ( _ptr, _index, __VA_ARGS__ ) ) |
| |
| #define BIT_ASSEMBLE_3( _ptr, _index, _field, _value, ... ) \ |
| ( BIT_ASSEMBLE_1 ( _ptr, _index, _field, _value ) | \ |
| BIT_ASSEMBLE_2 ( _ptr, _index, __VA_ARGS__ ) ) |
| |
| #define BIT_ASSEMBLE_4( _ptr, _index, _field, _value, ... ) \ |
| ( BIT_ASSEMBLE_1 ( _ptr, _index, _field, _value ) | \ |
| BIT_ASSEMBLE_3 ( _ptr, _index, __VA_ARGS__ ) ) |
| |
| #define BIT_ASSEMBLE_5( _ptr, _index, _field, _value, ... ) \ |
| ( BIT_ASSEMBLE_1 ( _ptr, _index, _field, _value ) | \ |
| BIT_ASSEMBLE_4 ( _ptr, _index, __VA_ARGS__ ) ) |
| |
| #define BIT_ASSEMBLE_6( _ptr, _index, _field, _value, ... ) \ |
| ( BIT_ASSEMBLE_1 ( _ptr, _index, _field, _value ) | \ |
| BIT_ASSEMBLE_5 ( _ptr, _index, __VA_ARGS__ ) ) |
| |
| #define BIT_ASSEMBLE_7( _ptr, _index, _field, _value, ... ) \ |
| ( BIT_ASSEMBLE_1 ( _ptr, _index, _field, _value ) | \ |
| BIT_ASSEMBLE_6 ( _ptr, _index, __VA_ARGS__ ) ) |
| |
| /* |
| * Build native-endian (positive) qword bitmasks from named fields |
| * |
| */ |
| |
| #define BIT_MASK_1( _ptr, _index, _field ) \ |
| ( BIT_MASK ( _ptr, _field ) << \ |
| QWORD_BIT_OFFSET ( _ptr, _index, _field ) ) |
| |
| #define BIT_MASK_2( _ptr, _index, _field, ... ) \ |
| ( BIT_MASK_1 ( _ptr, _index, _field ) | \ |
| BIT_MASK_1 ( _ptr, _index, __VA_ARGS__ ) ) |
| |
| #define BIT_MASK_3( _ptr, _index, _field, ... ) \ |
| ( BIT_MASK_1 ( _ptr, _index, _field ) | \ |
| BIT_MASK_2 ( _ptr, _index, __VA_ARGS__ ) ) |
| |
| #define BIT_MASK_4( _ptr, _index, _field, ... ) \ |
| ( BIT_MASK_1 ( _ptr, _index, _field ) | \ |
| BIT_MASK_3 ( _ptr, _index, __VA_ARGS__ ) ) |
| |
| #define BIT_MASK_5( _ptr, _index, _field, ... ) \ |
| ( BIT_MASK_1 ( _ptr, _index, _field ) | \ |
| BIT_MASK_4 ( _ptr, _index, __VA_ARGS__ ) ) |
| |
| #define BIT_MASK_6( _ptr, _index, _field, ... ) \ |
| ( BIT_MASK_1 ( _ptr, _index, _field ) | \ |
| BIT_MASK_5 ( _ptr, _index, __VA_ARGS__ ) ) |
| |
| #define BIT_MASK_7( _ptr, _index, _field, ... ) \ |
| ( BIT_MASK_1 ( _ptr, _index, _field ) | \ |
| BIT_MASK_6 ( _ptr, _index, __VA_ARGS__ ) ) |
| |
| /* |
| * Populate little-endian qwords from named fields and values |
| * |
| */ |
| |
| #define BIT_FILL( _ptr, _index, _assembled ) do { \ |
| uint64_t *__ptr = &(_ptr)->u.qwords[(_index)]; \ |
| uint64_t __assembled = (_assembled); \ |
| *__ptr = cpu_to_BIT64 ( __assembled ); \ |
| } while ( 0 ) |
| |
| #define BIT_FILL_1( _ptr, _field1, ... ) \ |
| BIT_FILL ( _ptr, QWORD_OFFSET ( _ptr, _field1 ), \ |
| BIT_ASSEMBLE_1 ( _ptr, QWORD_OFFSET ( _ptr, _field1 ), \ |
| _field1, __VA_ARGS__ ) ) |
| |
| #define BIT_FILL_2( _ptr, _field1, ... ) \ |
| BIT_FILL ( _ptr, QWORD_OFFSET ( _ptr, _field1 ), \ |
| BIT_ASSEMBLE_2 ( _ptr, QWORD_OFFSET ( _ptr, _field1 ), \ |
| _field1, __VA_ARGS__ ) ) |
| |
| #define BIT_FILL_3( _ptr, _field1, ... ) \ |
| BIT_FILL ( _ptr, QWORD_OFFSET ( _ptr, _field1 ), \ |
| BIT_ASSEMBLE_3 ( _ptr, QWORD_OFFSET ( _ptr, _field1 ), \ |
| _field1, __VA_ARGS__ ) ) |
| |
| #define BIT_FILL_4( _ptr, _field1, ... ) \ |
| BIT_FILL ( _ptr, QWORD_OFFSET ( _ptr, _field1 ), \ |
| BIT_ASSEMBLE_4 ( _ptr, QWORD_OFFSET ( _ptr, _field1 ), \ |
| _field1, __VA_ARGS__ ) ) |
| |
| #define BIT_FILL_5( _ptr, _field1, ... ) \ |
| BIT_FILL ( _ptr, QWORD_OFFSET ( _ptr, _field1 ), \ |
| BIT_ASSEMBLE_5 ( _ptr, QWORD_OFFSET ( _ptr, _field1 ), \ |
| _field1, __VA_ARGS__ ) ) |
| |
| #define BIT_FILL_6( _ptr, _field1, ... ) \ |
| BIT_FILL ( _ptr, QWORD_OFFSET ( _ptr, _field1 ), \ |
| BIT_ASSEMBLE_6 ( _ptr, QWORD_OFFSET ( _ptr, _field1 ), \ |
| _field1, __VA_ARGS__ ) ) |
| |
| /** Extract value of named field */ |
| #define BIT_GET64( _ptr, _field ) \ |
| ( { \ |
| unsigned int __index = QWORD_OFFSET ( _ptr, _field ); \ |
| uint64_t *__ptr = &(_ptr)->u.qwords[__index]; \ |
| uint64_t __value = BIT64_to_cpu ( *__ptr ); \ |
| __value >>= \ |
| QWORD_BIT_OFFSET ( _ptr, __index, _field ); \ |
| __value &= BIT_MASK ( _ptr, _field ); \ |
| __value; \ |
| } ) |
| |
| /** Extract value of named field (for fields up to the size of a long) */ |
| #define BIT_GET( _ptr, _field ) \ |
| ( ( unsigned long ) BIT_GET64 ( _ptr, _field ) ) |
| |
| #define BIT_SET( _ptr, _field, _value ) do { \ |
| unsigned int __index = QWORD_OFFSET ( _ptr, _field ); \ |
| uint64_t *__ptr = &(_ptr)->u.qwords[__index]; \ |
| unsigned int __shift = \ |
| QWORD_BIT_OFFSET ( _ptr, __index, _field ); \ |
| uint64_t __value = (_value); \ |
| *__ptr &= cpu_to_BIT64 ( ~( BIT_MASK ( _ptr, _field ) << \ |
| __shift ) ); \ |
| *__ptr |= cpu_to_BIT64 ( __value << __shift ); \ |
| } while ( 0 ) |
| |
| #endif /* _GPXE_BITOPS_H */ |