drivers/net/bcm5700/queue.h

   1 /******************************************************************************/
   2 /*                                                                            */
   3 /* Broadcom BCM5700 Linux Network Driver, Copyright (c) 2000 - 2004 Broadcom  */
   4 /* Corporation.                                                               */
   5 /* All rights reserved.                                                       */
   6 /*                                                                            */
   7 /* This program is free software; you can redistribute it and/or modify       */
   8 /* it under the terms of the GNU General Public License as published by       */
   9 /* the Free Software Foundation, located in the file LICENSE.                 */
  10 /*                                                                            */
  11 /* Queue functions.                                                           */
  12 /*    void          QQ_InitQueue(PQQ_CONTAINER pQueue)                        */
  13 /*    char          QQ_Full(PQQ_CONTAINER pQueue)                             */
  14 /*    char          QQ_Empty(PQQ_CONTAINER pQueue)                            */
  15 /*    unsigned int QQ_GetSize(PQQ_CONTAINER pQueue)                          */
  16 /*    unsigned int QQ_GetEntryCnt(PQQ_CONTAINER pQueue)                      */
  17 /*    char          QQ_PushHead(PQQ_CONTAINER pQueue, PQQ_ENTRY pEntry)       */
  18 /*    char          QQ_PushTail(PQQ_CONTAINER pQueue, PQQ_ENTRY pEntry)       */
  19 /*    PQQ_ENTRY     QQ_PopHead(PQQ_CONTAINER pQueue)                          */
  20 /*    PQQ_ENTRY     QQ_PopTail(PQQ_CONTAINER pQueue)                          */
  21 /*    PQQ_ENTRY     QQ_GetHead(PQQ_CONTAINER pQueue, unsigned int Idx)       */
  22 /*    PQQ_ENTRY     QQ_GetTail(PQQ_CONTAINER pQueue, unsigned int Idx)       */
  23 /*                                                                            */
  24 /*                                                                            */
  25 /* History:                                                                   */
  26 /*    02/25/00 Hav Khauv        Initial version.                              */
  27 /******************************************************************************/
  28
  29 #ifndef BCM_QUEUE_H
  30 #define BCM_QUEUE_H
  31
  32
  33
  34 /******************************************************************************/
  35 /* Queue definitions. */
  36 /******************************************************************************/
  37
  38 /* Entry for queueing. */
  39 typedef void *PQQ_ENTRY;
  40
  41
  42 /* Queue header -- base type. */
  43 typedef struct {
  44     unsigned int Head;
  45     unsigned int Tail;
  46     unsigned int Size;
  47     MM_ATOMIC_T EntryCnt;
  48     PQQ_ENTRY Array[1];
  49 } QQ_CONTAINER, *PQQ_CONTAINER;
  50
  51
  52 /* Declare queue type macro. */
  53 #define DECLARE_QUEUE_TYPE(_QUEUE_TYPE, _QUEUE_SIZE)            \
  54                                                                 \
  55     typedef struct {                                            \
  56         QQ_CONTAINER Container;                                 \
  57         PQQ_ENTRY EntryBuffer[_QUEUE_SIZE];                     \
  58     } _QUEUE_TYPE, *P##_QUEUE_TYPE
  59
  60
  61
  62 /******************************************************************************/
  63 /* Compilation switches. */
  64 /******************************************************************************/
  65
  66 #if DBG
  67 #undef QQ_NO_OVERFLOW_CHECK
  68 #undef QQ_NO_UNDERFLOW_CHECK
  69 #endif /* DBG */
  70
  71 #ifdef QQ_USE_MACROS
  72 /* notdone */
  73 #else
  74
  75 #ifdef QQ_NO_INLINE
  76 #define __inline
  77 #endif /* QQ_NO_INLINE */
  78
  79
  80
  81 /******************************************************************************/
  82 /* Description:                                                               */
  83 /*                                                                            */
  84 /* Return:                                                                    */
  85 /******************************************************************************/
  86 __inline static void
  87 QQ_InitQueue(
  88 PQQ_CONTAINER pQueue,
  89 unsigned int QueueSize) {
  90     pQueue->Head = 0;
  91     pQueue->Tail = 0;
  92     pQueue->Size = QueueSize+1;
  93     MM_ATOMIC_SET(&pQueue->EntryCnt, 0);
  94 } /* QQ_InitQueue */
  95
  96
  97
  98 /******************************************************************************/
  99 /* Description:                                                               */
 100 /*                                                                            */
 101 /* Return:                                                                    */
 102 /******************************************************************************/
 103 __inline static char
 104 QQ_Full(
 105 PQQ_CONTAINER pQueue) {
 106     unsigned int NewHead;
 107
 108     NewHead = (pQueue->Head + 1) % pQueue->Size;
 109
 110     return(NewHead == pQueue->Tail);
 111 } /* QQ_Full */
 112
 113
 114
 115 /******************************************************************************/
 116 /* Description:                                                               */
 117 /*                                                                            */
 118 /* Return:                                                                    */
 119 /******************************************************************************/
 120 __inline static char
 121 QQ_Empty(
 122 PQQ_CONTAINER pQueue) {
 123     return(pQueue->Head == pQueue->Tail);
 124 } /* QQ_Empty */
 125
 126
 127
 128 /******************************************************************************/
 129 /* Description:                                                               */
 130 /*                                                                            */
 131 /* Return:                                                                    */
 132 /******************************************************************************/
 133 __inline static unsigned int
 134 QQ_GetSize(
 135 PQQ_CONTAINER pQueue) {
 136     return pQueue->Size;
 137 } /* QQ_GetSize */
 138
 139
 140
 141 /******************************************************************************/
 142 /* Description:                                                               */
 143 /*                                                                            */
 144 /* Return:                                                                    */
 145 /******************************************************************************/
 146 __inline static unsigned int
 147 QQ_GetEntryCnt(
 148 PQQ_CONTAINER pQueue) {
 149     return MM_ATOMIC_READ(&pQueue->EntryCnt);
 150 } /* QQ_GetEntryCnt */
 151
 152
 153
 154 /******************************************************************************/
 155 /* Description:                                                               */
 156 /*                                                                            */
 157 /* Return:                                                                    */
 158 /*    TRUE entry was added successfully.                                      */
 159 /*    FALSE queue is full.                                                    */
 160 /******************************************************************************/
 161 __inline static char
 162 QQ_PushHead(
 163 PQQ_CONTAINER pQueue,
 164 PQQ_ENTRY pEntry) {
 165     unsigned int Head;
 166
 167     Head = (pQueue->Head + 1) % pQueue->Size;
 168
 169 #if !defined(QQ_NO_OVERFLOW_CHECK)
 170     if(Head == pQueue->Tail) {
 171         return 0;
 172     } /* if */
 173 #endif /* QQ_NO_OVERFLOW_CHECK */
 174
 175     pQueue->Array[pQueue->Head] = pEntry;
 176     MM_WMB();
 177     pQueue->Head = Head;
 178     MM_ATOMIC_INC(&pQueue->EntryCnt);
 179
 180     return -1;
 181 } /* QQ_PushHead */
 182
 183
 184
 185 /******************************************************************************/
 186 /* Description:                                                               */
 187 /*                                                                            */
 188 /* Return:                                                                    */
 189 /*    TRUE entry was added successfully.                                      */
 190 /*    FALSE queue is full.                                                    */
 191 /******************************************************************************/
 192 __inline static char
 193 QQ_PushTail(
 194 PQQ_CONTAINER pQueue,
 195 PQQ_ENTRY pEntry) {
 196     unsigned int Tail;
 197
 198     Tail = pQueue->Tail;
 199     if(Tail == 0) {
 200         Tail = pQueue->Size;
 201     } /* if */
 202     Tail--;
 203
 204 #if !defined(QQ_NO_OVERFLOW_CHECK)
 205     if(Tail == pQueue->Head) {
 206         return 0;
 207     } /* if */
 208 #endif /* QQ_NO_OVERFLOW_CHECK */
 209
 210     pQueue->Array[Tail] = pEntry;
 211     MM_WMB();
 212     pQueue->Tail = Tail;
 213     MM_ATOMIC_INC(&pQueue->EntryCnt);
 214
 215     return -1;
 216 } /* QQ_PushTail */
 217
 218
 219
 220 /******************************************************************************/
 221 /* Description:                                                               */
 222 /*                                                                            */
 223 /* Return:                                                                    */
 224 /******************************************************************************/
 225 __inline static PQQ_ENTRY
 226 QQ_PopHead(
 227 PQQ_CONTAINER pQueue) {
 228     unsigned int Head;
 229     unsigned int Tail;
 230     PQQ_ENTRY Entry;
 231
 232     Head = pQueue->Head;
 233     Tail = pQueue->Tail;
 234
 235     MM_MB();
 236 #if !defined(QQ_NO_UNDERFLOW_CHECK)
 237     if(Head == Tail) {
 238         return (PQQ_ENTRY) 0;
 239     } /* if */
 240 #endif /* QQ_NO_UNDERFLOW_CHECK */
 241
 242     if(Head == 0) {
 243         Head = pQueue->Size;
 244     } /* if */
 245     Head--;
 246
 247     Entry = pQueue->Array[Head];
 248     MM_MB();
 249     pQueue->Head = Head;
 250     MM_ATOMIC_DEC(&pQueue->EntryCnt);
 251
 252     return Entry;
 253 } /* QQ_PopHead */
 254
 255
 256
 257 /******************************************************************************/
 258 /* Description:                                                               */
 259 /*                                                                            */
 260 /* Return:                                                                    */
 261 /******************************************************************************/
 262 __inline static PQQ_ENTRY
 263 QQ_PopTail(
 264 PQQ_CONTAINER pQueue) {
 265     unsigned int Head;
 266     unsigned int Tail;
 267     PQQ_ENTRY Entry;
 268
 269     Head = pQueue->Head;
 270     Tail = pQueue->Tail;
 271
 272     MM_MB();
 273 #if !defined(QQ_NO_UNDERFLOW_CHECK)
 274     if(Tail == Head) {
 275         return (PQQ_ENTRY) 0;
 276     } /* if */
 277 #endif /* QQ_NO_UNDERFLOW_CHECK */
 278
 279     Entry = pQueue->Array[Tail];
 280     MM_MB();
 281     pQueue->Tail = (Tail + 1) % pQueue->Size;
 282     MM_ATOMIC_DEC(&pQueue->EntryCnt);
 283
 284     return Entry;
 285 } /* QQ_PopTail */
 286
 287
 288
 289 /******************************************************************************/
 290 /* Description:                                                               */
 291 /*                                                                            */
 292 /* Return:                                                                    */
 293 /******************************************************************************/
 294 __inline static PQQ_ENTRY
 295 QQ_GetHead(
 296     PQQ_CONTAINER pQueue,
 297     unsigned int Idx)
 298 {
 299     if(Idx >= (unsigned int) MM_ATOMIC_READ(&pQueue->EntryCnt))
 300     {
 301         return (PQQ_ENTRY) 0;
 302     }
 303
 304     if(pQueue->Head > Idx)
 305     {
 306         Idx = pQueue->Head - Idx;
 307     }
 308     else
 309     {
 310         Idx = pQueue->Size - (Idx - pQueue->Head);
 311     }
 312     Idx--;
 313
 314     return pQueue->Array[Idx];
 315 }
 316
 317
 318
 319 /******************************************************************************/
 320 /* Description:                                                               */
 321 /*                                                                            */
 322 /* Return:                                                                    */
 323 /******************************************************************************/
 324 __inline static PQQ_ENTRY
 325 QQ_GetTail(
 326     PQQ_CONTAINER pQueue,
 327     unsigned int Idx)
 328 {
 329     if(Idx >= (unsigned int) MM_ATOMIC_READ(&pQueue->EntryCnt))
 330     {
 331         return (PQQ_ENTRY) 0;
 332     }
 333
 334     Idx += pQueue->Tail;
 335     if(Idx >= pQueue->Size)
 336     {
 337         Idx = Idx - pQueue->Size;
 338     }
 339
 340     return pQueue->Array[Idx];
 341 }
 342
 343 #endif /* QQ_USE_MACROS */
 344
 345
 346
 347 #endif /* QUEUE_H */