| 1 | |
| 2 | /***************************************************************************** |
| 3 | |
| 4 | The following code is derived, directly or indirectly, from the SystemC |
| 5 | source code Copyright (c) 1996-2004 by all Contributors. |
| 6 | All Rights reserved. |
| 7 | |
| 8 | The contents of this file are subject to the restrictions and limitations |
| 9 | set forth in the SystemC Open Source License Version 2.4 (the "License"); |
| 10 | You may not use this file except in compliance with such restrictions and |
| 11 | limitations. You may obtain instructions on how to receive a copy of the |
| 12 | License at http://www.systemc.org/. Software distributed by Contributors |
| 13 | under the License is distributed on an "AS IS" basis, WITHOUT WARRANTY OF |
| 14 | ANY KIND, either express or implied. See the License for the specific |
| 15 | language governing rights and limitations under the License. |
| 16 | |
| 17 | *****************************************************************************/ |
| 18 | |
| 19 | |
| 20 | #ifndef TLM_FIFO_HEADER |
| 21 | #define TLM_FIFO_HEADER |
| 22 | |
| 23 | // |
| 24 | // This implements put, get and peek |
| 25 | // |
| 26 | // It also implements 0 and infinite size fifos - but the size |
| 27 | // zero fifos aren't rendezvous like zero length fifos, they simply are both |
| 28 | // full and empty at the same time. |
| 29 | // |
| 30 | // The size can be dynamically changed using the resize interface |
| 31 | // |
| 32 | // To get an infinite fifo use a -ve size in the constructor. |
| 33 | // The absolute value of the size is taken as the starting size of the |
| 34 | // actual physical buffer. |
| 35 | // |
| 36 | |
| 37 | #include <systemc.h> |
| 38 | |
| 39 | #include "tlm_core/tlm_interfaces/tlm_fifo_ifs.h" |
| 40 | #include "tlm_core/tlm_fifo/circular_buffer.h" |
| 41 | |
| 42 | |
| 43 | |
| 44 | template <class T> |
| 45 | class tlm_fifo : |
| 46 | public virtual tlm_fifo_get_if<T>, |
| 47 | public virtual tlm_fifo_put_if<T>, |
| 48 | public sc_prim_channel |
| 49 | { |
| 50 | public: |
| 51 | |
| 52 | // constructors |
| 53 | |
| 54 | explicit tlm_fifo( int size_ = 1 ) |
| 55 | : sc_prim_channel( sc_gen_unique_name( "fifo" ) ) { |
| 56 | |
| 57 | init( size_ ); |
| 58 | |
| 59 | } |
| 60 | |
| 61 | explicit tlm_fifo( const char* name_, int size_ = 1 ) |
| 62 | : sc_prim_channel( name_ ) { |
| 63 | |
| 64 | init( size_ ); |
| 65 | |
| 66 | } |
| 67 | |
| 68 | // destructor |
| 69 | |
| 70 | virtual ~tlm_fifo() { |
| 71 | |
| 72 | if( buffer != 0 ) delete buffer; |
| 73 | |
| 74 | } |
| 75 | |
| 76 | // tlm get interface |
| 77 | |
| 78 | T get( tlm_tag<T> *t = 0 ); |
| 79 | |
| 80 | bool nb_get( T& ); |
| 81 | bool nb_can_get( tlm_tag<T> *t = 0 ) const; |
| 82 | const sc_event &ok_to_get( tlm_tag<T> *t = 0 ) const { |
| 83 | return m_data_written_event; |
| 84 | } |
| 85 | |
| 86 | // tlm peek interface |
| 87 | |
| 88 | T peek( tlm_tag<T> *t = 0 ) const; |
| 89 | |
| 90 | bool nb_peek( T& ) const; |
| 91 | bool nb_can_peek( tlm_tag<T> *t = 0 ) const; |
| 92 | const sc_event &ok_to_peek( tlm_tag<T> *t = 0 ) const { |
| 93 | return m_data_written_event; |
| 94 | } |
| 95 | |
| 96 | // tlm put interface |
| 97 | |
| 98 | void put( const T& ); |
| 99 | |
| 100 | bool nb_put( const T& ); |
| 101 | bool nb_can_put( tlm_tag<T> *t = 0 ) const; |
| 102 | |
| 103 | const sc_event& ok_to_put( tlm_tag<T> *t = 0 ) const { |
| 104 | return m_data_read_event; |
| 105 | } |
| 106 | |
| 107 | // resize if |
| 108 | |
| 109 | void nb_expand( unsigned int n = 1 ); |
| 110 | void nb_unbound( unsigned int n = 16 ); |
| 111 | |
| 112 | bool nb_reduce( unsigned int n = 1 ); |
| 113 | bool nb_bound( unsigned int n ); |
| 114 | |
| 115 | // debug interface |
| 116 | |
| 117 | bool nb_peek( T & , int n ) const; |
| 118 | bool nb_poke( const T & , int n = 0 ); |
| 119 | |
| 120 | int used() const { |
| 121 | return m_num_readable - m_num_read; |
| 122 | } |
| 123 | |
| 124 | int size() const { |
| 125 | return m_size; |
| 126 | } |
| 127 | |
| 128 | void debug() const { |
| 129 | |
| 130 | if( is_empty() ) cout << "empty" << endl; |
| 131 | if( is_full() ) cout << "full" << endl; |
| 132 | |
| 133 | cout << "size " << size() << " - " << used() << " used " << endl; |
| 134 | cout << "readable " << m_num_readable << endl; |
| 135 | cout << "written/read " << m_num_written << "/" << m_num_read << endl; |
| 136 | |
| 137 | } |
| 138 | |
| 139 | // support functions |
| 140 | |
| 141 | static const char* const kind_string; |
| 142 | |
| 143 | const char* kind() const |
| 144 | { return kind_string; } |
| 145 | |
| 146 | |
| 147 | friend class tlm_annotated::tlm_annotated_fifo<T>; |
| 148 | |
| 149 | private: // some methods to support tlm_annotated_fifo ! |
| 150 | |
| 151 | bool nb_can_put( int count , tlm_tag<T> *t = 0 ) const { |
| 152 | if( m_size < 0 ) { |
| 153 | return true; |
| 154 | } |
| 155 | return m_num_readable + m_num_written + count <= m_size; |
| 156 | } |
| 157 | |
| 158 | bool nb_get_no_notify( T& ); |
| 159 | |
| 160 | protected: |
| 161 | sc_event &read_event( tlm_tag<T> *t = 0 ) { |
| 162 | return m_data_read_event; |
| 163 | } |
| 164 | |
| 165 | protected: |
| 166 | |
| 167 | void update(); |
| 168 | |
| 169 | // support methods |
| 170 | |
| 171 | void init( int ); |
| 172 | |
| 173 | protected: |
| 174 | |
| 175 | circular_buffer<T> *buffer; |
| 176 | |
| 177 | int m_size; // logical size of fifo |
| 178 | |
| 179 | int m_num_readable; // #samples readable |
| 180 | int m_num_read; // #samples read during this delta cycle |
| 181 | int m_num_written; // #samples written during this delta cycle |
| 182 | bool m_expand; // has an expand occurred during this delta cycle ? |
| 183 | int m_num_read_no_notify; // #samples read without notify during this delta cycle |
| 184 | |
| 185 | sc_event m_data_read_event; |
| 186 | sc_event m_data_written_event; |
| 187 | |
| 188 | private: |
| 189 | |
| 190 | // disabled |
| 191 | tlm_fifo( const tlm_fifo<T>& ); |
| 192 | tlm_fifo& operator = ( const tlm_fifo<T>& ); |
| 193 | |
| 194 | // |
| 195 | // use nb_can_get() and nb_can_put() rather than the following two |
| 196 | // private functions |
| 197 | // |
| 198 | |
| 199 | bool is_empty() const { |
| 200 | return used() == 0; |
| 201 | } |
| 202 | |
| 203 | bool is_full() const { |
| 204 | return size() == m_num_readable + m_num_written; |
| 205 | } |
| 206 | |
| 207 | }; |
| 208 | |
| 209 | template <typename T> |
| 210 | const char* const tlm_fifo<T>::kind_string = "tlm_fifo"; |
| 211 | |
| 212 | |
| 213 | /****************************************************************** |
| 214 | // |
| 215 | // init and update |
| 216 | // |
| 217 | ******************************************************************/ |
| 218 | |
| 219 | template< typename T > |
| 220 | inline |
| 221 | void |
| 222 | tlm_fifo<T>::init( int size_ ) { |
| 223 | |
| 224 | if( size_ > 0 ) { |
| 225 | buffer = new circular_buffer<T>( size_); |
| 226 | } |
| 227 | |
| 228 | else if( size_ < 0 ) { |
| 229 | buffer = new circular_buffer<T>( -size_ ); |
| 230 | } |
| 231 | |
| 232 | else { |
| 233 | buffer = new circular_buffer<T>( 16 ); |
| 234 | } |
| 235 | |
| 236 | m_size = size_; |
| 237 | m_num_readable = 0; |
| 238 | m_num_read = 0; |
| 239 | m_num_written = 0; |
| 240 | m_expand = false; |
| 241 | m_num_read_no_notify = false; |
| 242 | |
| 243 | } |
| 244 | |
| 245 | template < typename T> |
| 246 | inline |
| 247 | void |
| 248 | tlm_fifo<T>::update() |
| 249 | { |
| 250 | if( m_num_read > m_num_read_no_notify || m_expand ) { |
| 251 | m_data_read_event.notify( SC_ZERO_TIME ); |
| 252 | } |
| 253 | |
| 254 | if( m_num_written > 0 ) { |
| 255 | m_data_written_event.notify( SC_ZERO_TIME ); |
| 256 | } |
| 257 | |
| 258 | m_expand = false; |
| 259 | m_num_read = 0; |
| 260 | m_num_written = 0; |
| 261 | m_num_readable = buffer->used(); |
| 262 | m_num_read_no_notify = 0; |
| 263 | |
| 264 | } |
| 265 | |
| 266 | #include "tlm_core/tlm_fifo/tlm_fifo_put_get.h" |
| 267 | #include "tlm_core/tlm_fifo/tlm_fifo_peek.h" |
| 268 | #include "tlm_core/tlm_fifo/tlm_fifo_resize.h" |
| 269 | |
| 270 | #endif |
| 271 | |