kernel/2.6.29.6-aldebaran-rt/drivers/net/wireless/rt2x00/rt2x00queue.h

   1 /*
   2         Copyright (C) 2004 - 2008 rt2x00 SourceForge Project
   3         <http://rt2x00.serialmonkey.com>
   4
   5         This program is free software; you can redistribute it and/or modify
   6         it under the terms of the GNU General Public License as published by
   7         the Free Software Foundation; either version 2 of the License, or
   8         (at your option) any later version.
   9
  10         This program is distributed in the hope that it will be useful,
  11         but WITHOUT ANY WARRANTY; without even the implied warranty of
  12         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13         GNU General Public License for more details.
  14
  15         You should have received a copy of the GNU General Public License
  16         along with this program; if not, write to the
  17         Free Software Foundation, Inc.,
  18         59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19  */
  20
  21 /*
  22         Module: rt2x00
  23         Abstract: rt2x00 queue datastructures and routines
  24  */
  25
  26 #ifndef RT2X00QUEUE_H
  27 #define RT2X00QUEUE_H
  28
  29 #include <linux/prefetch.h>
  30
  31 /**
  32  * DOC: Entrie frame size
  33  *
  34  * Ralink PCI devices demand the Frame size to be a multiple of 128 bytes,
  35  * for USB devices this restriction does not apply, but the value of
  36  * 2432 makes sense since it is big enough to contain the maximum fragment
  37  * size according to the ieee802.11 specs.
  38  */
  39 #define DATA_FRAME_SIZE 2432
  40 #define MGMT_FRAME_SIZE 256
  41
  42 /**
  43  * DOC: Number of entries per queue
  44  *
  45  * Under normal load without fragmentation 12 entries are sufficient
  46  * without the queue being filled up to the maximum. When using fragmentation
  47  * and the queue threshold code we need to add some additional margins to
  48  * make sure the queue will never (or only under extreme load) fill up
  49  * completely.
  50  * Since we don't use preallocated DMA having a large number of queue entries
  51  * will have only minimal impact on the memory requirements for the queue.
  52  */
  53 #define RX_ENTRIES      24
  54 #define TX_ENTRIES      24
  55 #define BEACON_ENTRIES  1
  56 #define ATIM_ENTRIES    8
  57
  58 /**
  59  * enum data_queue_qid: Queue identification
  60  *
  61  * @QID_AC_BE: AC BE queue
  62  * @QID_AC_BK: AC BK queue
  63  * @QID_AC_VI: AC VI queue
  64  * @QID_AC_VO: AC VO queue
  65  * @QID_HCCA: HCCA queue
  66  * @QID_MGMT: MGMT queue (prio queue)
  67  * @QID_RX: RX queue
  68  * @QID_OTHER: None of the above (don't use, only present for completeness)
  69  * @QID_BEACON: Beacon queue (value unspecified, don't send it to device)
  70  * @QID_ATIM: Atim queue (value unspeficied, don't send it to device)
  71  */
  72 enum data_queue_qid {
  73         QID_AC_BE = 0,
  74         QID_AC_BK = 1,
  75         QID_AC_VI = 2,
  76         QID_AC_VO = 3,
  77         QID_HCCA = 4,
  78         QID_MGMT = 13,
  79         QID_RX = 14,
  80         QID_OTHER = 15,
  81         QID_BEACON,
  82         QID_ATIM,
  83 };
  84
  85 /**
  86  * enum skb_frame_desc_flags: Flags for &struct skb_frame_desc
  87  *
  88  * @SKBDESC_DMA_MAPPED_RX: &skb_dma field has been mapped for RX
  89  * @SKBDESC_DMA_MAPPED_TX: &skb_dma field has been mapped for TX
  90  * @FRAME_DESC_IV_STRIPPED: Frame contained a IV/EIV provided by
  91  *      mac80211 but was stripped for processing by the driver.
  92  */
  93 enum skb_frame_desc_flags {
  94         SKBDESC_DMA_MAPPED_RX = 1 << 0,
  95         SKBDESC_DMA_MAPPED_TX = 1 << 1,
  96         FRAME_DESC_IV_STRIPPED = 1 << 2,
  97 };
  98
  99 /**
 100  * struct skb_frame_desc: Descriptor information for the skb buffer
 101  *
 102  * This structure is placed over the driver_data array, this means that
 103  * this structure should not exceed the size of that array (40 bytes).
 104  *
 105  * @flags: Frame flags, see &enum skb_frame_desc_flags.
 106  * @desc_len: Length of the frame descriptor.
 107  * @tx_rate_idx: the index of the TX rate, used for TX status reporting
 108  * @tx_rate_flags: the TX rate flags, used for TX status reporting
 109  * @desc: Pointer to descriptor part of the frame.
 110  *      Note that this pointer could point to something outside
 111  *      of the scope of the skb->data pointer.
 112  * @iv: IV/EIV data used during encryption/decryption.
 113  * @skb_dma: (PCI-only) the DMA address associated with the sk buffer.
 114  * @entry: The entry to which this sk buffer belongs.
 115  */
 116 struct skb_frame_desc {
 117         u8 flags;
 118
 119         u8 desc_len;
 120         u8 tx_rate_idx;
 121         u8 tx_rate_flags;
 122
 123         void *desc;
 124
 125         __le32 iv[2];
 126
 127         dma_addr_t skb_dma;
 128
 129         struct queue_entry *entry;
 130 };
 131
 132 /**
 133  * get_skb_frame_desc - Obtain the rt2x00 frame descriptor from a sk_buff.
 134  * @skb: &struct sk_buff from where we obtain the &struct skb_frame_desc
 135  */
 136 static inline struct skb_frame_desc* get_skb_frame_desc(struct sk_buff *skb)
 137 {
 138         BUILD_BUG_ON(sizeof(struct skb_frame_desc) >
 139                      IEEE80211_TX_INFO_DRIVER_DATA_SIZE);
 140         return (struct skb_frame_desc *)&IEEE80211_SKB_CB(skb)->driver_data;
 141 }
 142
 143 /**
 144  * enum rxdone_entry_desc_flags: Flags for &struct rxdone_entry_desc
 145  *
 146  * @RXDONE_SIGNAL_PLCP: Signal field contains the plcp value.
 147  * @RXDONE_SIGNAL_BITRATE: Signal field contains the bitrate value.
 148  * @RXDONE_MY_BSS: Does this frame originate from device's BSS.
 149  * @RXDONE_CRYPTO_IV: Driver provided IV/EIV data.
 150  * @RXDONE_CRYPTO_ICV: Driver provided ICV data.
 151  */
 152 enum rxdone_entry_desc_flags {
 153         RXDONE_SIGNAL_PLCP = 1 << 0,
 154         RXDONE_SIGNAL_BITRATE = 1 << 1,
 155         RXDONE_MY_BSS = 1 << 2,
 156         RXDONE_CRYPTO_IV = 1 << 3,
 157         RXDONE_CRYPTO_ICV = 1 << 4,
 158 };
 159
 160 /**
 161  * struct rxdone_entry_desc: RX Entry descriptor
 162  *
 163  * Summary of information that has been read from the RX frame descriptor.
 164  *
 165  * @timestamp: RX Timestamp
 166  * @signal: Signal of the received frame.
 167  * @rssi: RSSI of the received frame.
 168  * @size: Data size of the received frame.
 169  * @flags: MAC80211 receive flags (See &enum mac80211_rx_flags).
 170  * @dev_flags: Ralink receive flags (See &enum rxdone_entry_desc_flags).
 171  * @cipher: Cipher type used during decryption.
 172  * @cipher_status: Decryption status.
 173  * @iv: IV/EIV data used during decryption.
 174  * @icv: ICV data used during decryption.
 175  */
 176 struct rxdone_entry_desc {
 177         u64 timestamp;
 178         int signal;
 179         int rssi;
 180         int size;
 181         int flags;
 182         int dev_flags;
 183         u8 cipher;
 184         u8 cipher_status;
 185
 186         __le32 iv[2];
 187         __le32 icv;
 188 };
 189
 190 /**
 191  * enum txdone_entry_desc_flags: Flags for &struct txdone_entry_desc
 192  *
 193  * @TXDONE_UNKNOWN: Hardware could not determine success of transmission.
 194  * @TXDONE_SUCCESS: Frame was successfully send
 195  * @TXDONE_FAILURE: Frame was not successfully send
 196  * @TXDONE_EXCESSIVE_RETRY: In addition to &TXDONE_FAILURE, the
 197  *      frame transmission failed due to excessive retries.
 198  */
 199 enum txdone_entry_desc_flags {
 200         TXDONE_UNKNOWN,
 201         TXDONE_SUCCESS,
 202         TXDONE_FAILURE,
 203         TXDONE_EXCESSIVE_RETRY,
 204 };
 205
 206 /**
 207  * struct txdone_entry_desc: TX done entry descriptor
 208  *
 209  * Summary of information that has been read from the TX frame descriptor
 210  * after the device is done with transmission.
 211  *
 212  * @flags: TX done flags (See &enum txdone_entry_desc_flags).
 213  * @retry: Retry count.
 214  */
 215 struct txdone_entry_desc {
 216         unsigned long flags;
 217         int retry;
 218 };
 219
 220 /**
 221  * enum txentry_desc_flags: Status flags for TX entry descriptor
 222  *
 223  * @ENTRY_TXD_RTS_FRAME: This frame is a RTS frame.
 224  * @ENTRY_TXD_CTS_FRAME: This frame is a CTS-to-self frame.
 225  * @ENTRY_TXD_OFDM_RATE: This frame is send out with an OFDM rate.
 226  * @ENTRY_TXD_GENERATE_SEQ: This frame requires sequence counter.
 227  * @ENTRY_TXD_FIRST_FRAGMENT: This is the first frame.
 228  * @ENTRY_TXD_MORE_FRAG: This frame is followed by another fragment.
 229  * @ENTRY_TXD_REQ_TIMESTAMP: Require timestamp to be inserted.
 230  * @ENTRY_TXD_BURST: This frame belongs to the same burst event.
 231  * @ENTRY_TXD_ACK: An ACK is required for this frame.
 232  * @ENTRY_TXD_RETRY_MODE: When set, the long retry count is used.
 233  * @ENTRY_TXD_ENCRYPT: This frame should be encrypted.
 234  * @ENTRY_TXD_ENCRYPT_PAIRWISE: Use pairwise key table (instead of shared).
 235  * @ENTRY_TXD_ENCRYPT_IV: Generate IV/EIV in hardware.
 236  * @ENTRY_TXD_ENCRYPT_MMIC: Generate MIC in hardware.
 237  */
 238 enum txentry_desc_flags {
 239         ENTRY_TXD_RTS_FRAME,
 240         ENTRY_TXD_CTS_FRAME,
 241         ENTRY_TXD_OFDM_RATE,
 242         ENTRY_TXD_GENERATE_SEQ,
 243         ENTRY_TXD_FIRST_FRAGMENT,
 244         ENTRY_TXD_MORE_FRAG,
 245         ENTRY_TXD_REQ_TIMESTAMP,
 246         ENTRY_TXD_BURST,
 247         ENTRY_TXD_ACK,
 248         ENTRY_TXD_RETRY_MODE,
 249         ENTRY_TXD_ENCRYPT,
 250         ENTRY_TXD_ENCRYPT_PAIRWISE,
 251         ENTRY_TXD_ENCRYPT_IV,
 252         ENTRY_TXD_ENCRYPT_MMIC,
 253 };
 254
 255 /**
 256  * struct txentry_desc: TX Entry descriptor
 257  *
 258  * Summary of information for the frame descriptor before sending a TX frame.
 259  *
 260  * @flags: Descriptor flags (See &enum queue_entry_flags).
 261  * @queue: Queue identification (See &enum data_queue_qid).
 262  * @length_high: PLCP length high word.
 263  * @length_low: PLCP length low word.
 264  * @signal: PLCP signal.
 265  * @service: PLCP service.
 266  * @retry_limit: Max number of retries.
 267  * @aifs: AIFS value.
 268  * @ifs: IFS value.
 269  * @cw_min: cwmin value.
 270  * @cw_max: cwmax value.
 271  * @cipher: Cipher type used for encryption.
 272  * @key_idx: Key index used for encryption.
 273  * @iv_offset: Position where IV should be inserted by hardware.
 274  */
 275 struct txentry_desc {
 276         unsigned long flags;
 277
 278         enum data_queue_qid queue;
 279
 280         u16 length_high;
 281         u16 length_low;
 282         u16 signal;
 283         u16 service;
 284
 285         short retry_limit;
 286         short aifs;
 287         short ifs;
 288         short cw_min;
 289         short cw_max;
 290
 291         enum cipher cipher;
 292         u16 key_idx;
 293         u16 iv_offset;
 294 };
 295
 296 /**
 297  * enum queue_entry_flags: Status flags for queue entry
 298  *
 299  * @ENTRY_BCN_ASSIGNED: This entry has been assigned to an interface.
 300  *      As long as this bit is set, this entry may only be touched
 301  *      through the interface structure.
 302  * @ENTRY_OWNER_DEVICE_DATA: This entry is owned by the device for data
 303  *      transfer (either TX or RX depending on the queue). The entry should
 304  *      only be touched after the device has signaled it is done with it.
 305  * @ENTRY_OWNER_DEVICE_CRYPTO: This entry is owned by the device for data
 306  *      encryption or decryption. The entry should only be touched after
 307  *      the device has signaled it is done with it.
 308  * @ENTRY_DATA_PENDING: This entry contains a valid frame and is waiting
 309  *      for the signal to start sending.
 310  */
 311 enum queue_entry_flags {
 312         ENTRY_BCN_ASSIGNED,
 313         ENTRY_OWNER_DEVICE_DATA,
 314         ENTRY_OWNER_DEVICE_CRYPTO,
 315         ENTRY_DATA_PENDING,
 316 };
 317
 318 /**
 319  * struct queue_entry: Entry inside the &struct data_queue
 320  *
 321  * @flags: Entry flags, see &enum queue_entry_flags.
 322  * @queue: The data queue (&struct data_queue) to which this entry belongs.
 323  * @skb: The buffer which is currently being transmitted (for TX queue),
 324  *      or used to directly recieve data in (for RX queue).
 325  * @entry_idx: The entry index number.
 326  * @priv_data: Private data belonging to this queue entry. The pointer
 327  *      points to data specific to a particular driver and queue type.
 328  */
 329 struct queue_entry {
 330         unsigned long flags;
 331
 332         struct data_queue *queue;
 333
 334         struct sk_buff *skb;
 335
 336         unsigned int entry_idx;
 337
 338         void *priv_data;
 339 };
 340
 341 /**
 342  * enum queue_index: Queue index type
 343  *
 344  * @Q_INDEX: Index pointer to the current entry in the queue, if this entry is
 345  *      owned by the hardware then the queue is considered to be full.
 346  * @Q_INDEX_DONE: Index pointer to the next entry which will be completed by
 347  *      the hardware and for which we need to run the txdone handler. If this
 348  *      entry is not owned by the hardware the queue is considered to be empty.
 349  * @Q_INDEX_CRYPTO: Index pointer to the next entry which encryption/decription
 350  *      will be completed by the hardware next.
 351  * @Q_INDEX_MAX: Keep last, used in &struct data_queue to determine the size
 352  *      of the index array.
 353  */
 354 enum queue_index {
 355         Q_INDEX,
 356         Q_INDEX_DONE,
 357         Q_INDEX_CRYPTO,
 358         Q_INDEX_MAX,
 359 };
 360
 361 /**
 362  * struct data_queue: Data queue
 363  *
 364  * @rt2x00dev: Pointer to main &struct rt2x00dev where this queue belongs to.
 365  * @entries: Base address of the &struct queue_entry which are
 366  *      part of this queue.
 367  * @qid: The queue identification, see &enum data_queue_qid.
 368  * @lock: Spinlock to protect index handling. Whenever @index, @index_done or
 369  *      @index_crypt needs to be changed this lock should be grabbed to prevent
 370  *      index corruption due to concurrency.
 371  * @count: Number of frames handled in the queue.
 372  * @limit: Maximum number of entries in the queue.
 373  * @threshold: Minimum number of free entries before queue is kicked by force.
 374  * @length: Number of frames in queue.
 375  * @index: Index pointers to entry positions in the queue,
 376  *      use &enum queue_index to get a specific index field.
 377  * @txop: maximum burst time.
 378  * @aifs: The aifs value for outgoing frames (field ignored in RX queue).
 379  * @cw_min: The cw min value for outgoing frames (field ignored in RX queue).
 380  * @cw_max: The cw max value for outgoing frames (field ignored in RX queue).
 381  * @data_size: Maximum data size for the frames in this queue.
 382  * @desc_size: Hardware descriptor size for the data in this queue.
 383  * @usb_endpoint: Device endpoint used for communication (USB only)
 384  * @usb_maxpacket: Max packet size for given endpoint (USB only)
 385  */
 386 struct data_queue {
 387         struct rt2x00_dev *rt2x00dev;
 388         struct queue_entry *entries;
 389
 390         enum data_queue_qid qid;
 391
 392         spinlock_t lock;
 393         unsigned int count;
 394         unsigned short limit;
 395         unsigned short threshold;
 396         unsigned short length;
 397         unsigned short index[Q_INDEX_MAX];
 398
 399         unsigned short txop;
 400         unsigned short aifs;
 401         unsigned short cw_min;
 402         unsigned short cw_max;
 403
 404         unsigned short data_size;
 405         unsigned short desc_size;
 406
 407         unsigned short usb_endpoint;
 408         unsigned short usb_maxpacket;
 409 };
 410
 411 /**
 412  * struct data_queue_desc: Data queue description
 413  *
 414  * The information in this structure is used by drivers
 415  * to inform rt2x00lib about the creation of the data queue.
 416  *
 417  * @entry_num: Maximum number of entries for a queue.
 418  * @data_size: Maximum data size for the frames in this queue.
 419  * @desc_size: Hardware descriptor size for the data in this queue.
 420  * @priv_size: Size of per-queue_entry private data.
 421  */
 422 struct data_queue_desc {
 423         unsigned short entry_num;
 424         unsigned short data_size;
 425         unsigned short desc_size;
 426         unsigned short priv_size;
 427 };
 428
 429 /**
 430  * queue_end - Return pointer to the last queue (HELPER MACRO).
 431  * @__dev: Pointer to &struct rt2x00_dev
 432  *
 433  * Using the base rx pointer and the maximum number of available queues,
 434  * this macro will return the address of 1 position beyond  the end of the
 435  * queues array.
 436  */
 437 #define queue_end(__dev) \
 438         &(__dev)->rx[(__dev)->data_queues]
 439
 440 /**
 441  * tx_queue_end - Return pointer to the last TX queue (HELPER MACRO).
 442  * @__dev: Pointer to &struct rt2x00_dev
 443  *
 444  * Using the base tx pointer and the maximum number of available TX
 445  * queues, this macro will return the address of 1 position beyond
 446  * the end of the TX queue array.
 447  */
 448 #define tx_queue_end(__dev) \
 449         &(__dev)->tx[(__dev)->ops->tx_queues]
 450
 451 /**
 452  * queue_next - Return pointer to next queue in list (HELPER MACRO).
 453  * @__queue: Current queue for which we need the next queue
 454  *
 455  * Using the current queue address we take the address directly
 456  * after the queue to take the next queue. Note that this macro
 457  * should be used carefully since it does not protect against
 458  * moving past the end of the list. (See macros &queue_end and
 459  * &tx_queue_end for determining the end of the queue).
 460  */
 461 #define queue_next(__queue) \
 462         &(__queue)[1]
 463
 464 /**
 465  * queue_loop - Loop through the queues within a specific range (HELPER MACRO).
 466  * @__entry: Pointer where the current queue entry will be stored in.
 467  * @__start: Start queue pointer.
 468  * @__end: End queue pointer.
 469  *
 470  * This macro will loop through all queues between &__start and &__end.
 471  */
 472 #define queue_loop(__entry, __start, __end)                     \
 473         for ((__entry) = (__start);                             \
 474              prefetch(queue_next(__entry)), (__entry) != (__end);\
 475              (__entry) = queue_next(__entry))
 476
 477 /**
 478  * queue_for_each - Loop through all queues
 479  * @__dev: Pointer to &struct rt2x00_dev
 480  * @__entry: Pointer where the current queue entry will be stored in.
 481  *
 482  * This macro will loop through all available queues.
 483  */
 484 #define queue_for_each(__dev, __entry) \
 485         queue_loop(__entry, (__dev)->rx, queue_end(__dev))
 486
 487 /**
 488  * tx_queue_for_each - Loop through the TX queues
 489  * @__dev: Pointer to &struct rt2x00_dev
 490  * @__entry: Pointer where the current queue entry will be stored in.
 491  *
 492  * This macro will loop through all TX related queues excluding
 493  * the Beacon and Atim queues.
 494  */
 495 #define tx_queue_for_each(__dev, __entry) \
 496         queue_loop(__entry, (__dev)->tx, tx_queue_end(__dev))
 497
 498 /**
 499  * txall_queue_for_each - Loop through all TX related queues
 500  * @__dev: Pointer to &struct rt2x00_dev
 501  * @__entry: Pointer where the current queue entry will be stored in.
 502  *
 503  * This macro will loop through all TX related queues including
 504  * the Beacon and Atim queues.
 505  */
 506 #define txall_queue_for_each(__dev, __entry) \
 507         queue_loop(__entry, (__dev)->tx, queue_end(__dev))
 508
 509 /**
 510  * rt2x00queue_empty - Check if the queue is empty.
 511  * @queue: Queue to check if empty.
 512  */
 513 static inline int rt2x00queue_empty(struct data_queue *queue)
 514 {
 515         return queue->length == 0;
 516 }
 517
 518 /**
 519  * rt2x00queue_full - Check if the queue is full.
 520  * @queue: Queue to check if full.
 521  */
 522 static inline int rt2x00queue_full(struct data_queue *queue)
 523 {
 524         return queue->length == queue->limit;
 525 }
 526
 527 /**
 528  * rt2x00queue_free - Check the number of available entries in queue.
 529  * @queue: Queue to check.
 530  */
 531 static inline int rt2x00queue_available(struct data_queue *queue)
 532 {
 533         return queue->limit - queue->length;
 534 }
 535
 536 /**
 537  * rt2x00queue_threshold - Check if the queue is below threshold
 538  * @queue: Queue to check.
 539  */
 540 static inline int rt2x00queue_threshold(struct data_queue *queue)
 541 {
 542         return rt2x00queue_available(queue) < queue->threshold;
 543 }
 544
 545 /**
 546  * _rt2x00_desc_read - Read a word from the hardware descriptor.
 547  * @desc: Base descriptor address
 548  * @word: Word index from where the descriptor should be read.
 549  * @value: Address where the descriptor value should be written into.
 550  */
 551 static inline void _rt2x00_desc_read(__le32 *desc, const u8 word, __le32 *value)
 552 {
 553         *value = desc[word];
 554 }
 555
 556 /**
 557  * rt2x00_desc_read - Read a word from the hardware descriptor, this
 558  * function will take care of the byte ordering.
 559  * @desc: Base descriptor address
 560  * @word: Word index from where the descriptor should be read.
 561  * @value: Address where the descriptor value should be written into.
 562  */
 563 static inline void rt2x00_desc_read(__le32 *desc, const u8 word, u32 *value)
 564 {
 565         __le32 tmp;
 566         _rt2x00_desc_read(desc, word, &tmp);
 567         *value = le32_to_cpu(tmp);
 568 }
 569
 570 /**
 571  * rt2x00_desc_write - write a word to the hardware descriptor, this
 572  * function will take care of the byte ordering.
 573  * @desc: Base descriptor address
 574  * @word: Word index from where the descriptor should be written.
 575  * @value: Value that should be written into the descriptor.
 576  */
 577 static inline void _rt2x00_desc_write(__le32 *desc, const u8 word, __le32 value)
 578 {
 579         desc[word] = value;
 580 }
 581
 582 /**
 583  * rt2x00_desc_write - write a word to the hardware descriptor.
 584  * @desc: Base descriptor address
 585  * @word: Word index from where the descriptor should be written.
 586  * @value: Value that should be written into the descriptor.
 587  */
 588 static inline void rt2x00_desc_write(__le32 *desc, const u8 word, u32 value)
 589 {
 590         _rt2x00_desc_write(desc, word, cpu_to_le32(value));
 591 }
 592
 593 #endif /* RT2X00QUEUE_H */