2 Copyright (C) 2004 - 2008 rt2x00 SourceForge Project
3 <http://rt2x00.serialmonkey.com>
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23 Abstract: rt2x00 queue datastructures and routines
29 #include <linux/prefetch.h>
32 * DOC: Entrie frame size
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.
39 #define DATA_FRAME_SIZE 2432
40 #define MGMT_FRAME_SIZE 256
43 * DOC: Number of entries per queue
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
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.
55 #define BEACON_ENTRIES 1
56 #define ATIM_ENTRIES 8
59 * enum data_queue_qid: Queue identification
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)
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)
86 * enum skb_frame_desc_flags: Flags for &struct skb_frame_desc
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.
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,
100 * struct skb_frame_desc: Descriptor information for the skb buffer
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).
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 data used during encryption/decryption.
113 * @eiv: EIV data used during encryption/decryption.
114 * @skb_dma: (PCI-only) the DMA address associated with the sk buffer.
115 * @entry: The entry to which this sk buffer belongs.
117 struct skb_frame_desc {
131 struct queue_entry *entry;
135 * get_skb_frame_desc - Obtain the rt2x00 frame descriptor from a sk_buff.
136 * @skb: &struct sk_buff from where we obtain the &struct skb_frame_desc
138 static inline struct skb_frame_desc* get_skb_frame_desc(struct sk_buff *skb)
140 BUILD_BUG_ON(sizeof(struct skb_frame_desc) >
141 IEEE80211_TX_INFO_DRIVER_DATA_SIZE);
142 return (struct skb_frame_desc *)&IEEE80211_SKB_CB(skb)->driver_data;
146 * enum rxdone_entry_desc_flags: Flags for &struct rxdone_entry_desc
148 * @RXDONE_SIGNAL_PLCP: Signal field contains the plcp value.
149 * @RXDONE_SIGNAL_BITRATE: Signal field contains the bitrate value.
150 * @RXDONE_MY_BSS: Does this frame originate from device's BSS.
152 enum rxdone_entry_desc_flags {
153 RXDONE_SIGNAL_PLCP = 1 << 0,
154 RXDONE_SIGNAL_BITRATE = 1 << 1,
155 RXDONE_MY_BSS = 1 << 2,
159 * struct rxdone_entry_desc: RX Entry descriptor
161 * Summary of information that has been read from the RX frame descriptor.
163 * @timestamp: RX Timestamp
164 * @signal: Signal of the received frame.
165 * @rssi: RSSI of the received frame.
166 * @size: Data size of the received frame.
167 * @flags: MAC80211 receive flags (See &enum mac80211_rx_flags).
168 * @dev_flags: Ralink receive flags (See &enum rxdone_entry_desc_flags).
169 * @cipher: Cipher type used during decryption.
170 * @cipher_status: Decryption status.
171 * @iv: IV data used during decryption.
172 * @eiv: EIV data used during decryption.
173 * @icv: ICV data used during decryption.
175 struct rxdone_entry_desc {
191 * enum txdone_entry_desc_flags: Flags for &struct txdone_entry_desc
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.
199 enum txdone_entry_desc_flags {
203 TXDONE_EXCESSIVE_RETRY,
207 * struct txdone_entry_desc: TX done entry descriptor
209 * Summary of information that has been read from the TX frame descriptor
210 * after the device is done with transmission.
212 * @flags: TX done flags (See &enum txdone_entry_desc_flags).
213 * @retry: Retry count.
215 struct txdone_entry_desc {
221 * enum txentry_desc_flags: Status flags for TX entry descriptor
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.
238 enum txentry_desc_flags {
242 ENTRY_TXD_GENERATE_SEQ,
243 ENTRY_TXD_FIRST_FRAGMENT,
245 ENTRY_TXD_REQ_TIMESTAMP,
248 ENTRY_TXD_RETRY_MODE,
250 ENTRY_TXD_ENCRYPT_PAIRWISE,
251 ENTRY_TXD_ENCRYPT_IV,
252 ENTRY_TXD_ENCRYPT_MMIC,
256 * struct txentry_desc: TX Entry descriptor
258 * Summary of information for the frame descriptor before sending a TX frame.
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.
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.
275 struct txentry_desc {
278 enum data_queue_qid queue;
297 * enum queue_entry_flags: Status flags for queue entry
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.
311 enum queue_entry_flags {
313 ENTRY_OWNER_DEVICE_DATA,
314 ENTRY_OWNER_DEVICE_CRYPTO,
319 * struct queue_entry: Entry inside the &struct data_queue
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.
332 struct data_queue *queue;
336 unsigned int entry_idx;
342 * enum queue_index: Queue index type
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.
362 * struct data_queue: Data queue
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.
385 struct rt2x00_dev *rt2x00dev;
386 struct queue_entry *entries;
388 enum data_queue_qid qid;
392 unsigned short limit;
393 unsigned short threshold;
394 unsigned short length;
395 unsigned short index[Q_INDEX_MAX];
399 unsigned short cw_min;
400 unsigned short cw_max;
402 unsigned short data_size;
403 unsigned short desc_size;
407 * struct data_queue_desc: Data queue description
409 * The information in this structure is used by drivers
410 * to inform rt2x00lib about the creation of the data queue.
412 * @entry_num: Maximum number of entries for a queue.
413 * @data_size: Maximum data size for the frames in this queue.
414 * @desc_size: Hardware descriptor size for the data in this queue.
415 * @priv_size: Size of per-queue_entry private data.
417 struct data_queue_desc {
418 unsigned short entry_num;
419 unsigned short data_size;
420 unsigned short desc_size;
421 unsigned short priv_size;
425 * queue_end - Return pointer to the last queue (HELPER MACRO).
426 * @__dev: Pointer to &struct rt2x00_dev
428 * Using the base rx pointer and the maximum number of available queues,
429 * this macro will return the address of 1 position beyond the end of the
432 #define queue_end(__dev) \
433 &(__dev)->rx[(__dev)->data_queues]
436 * tx_queue_end - Return pointer to the last TX queue (HELPER MACRO).
437 * @__dev: Pointer to &struct rt2x00_dev
439 * Using the base tx pointer and the maximum number of available TX
440 * queues, this macro will return the address of 1 position beyond
441 * the end of the TX queue array.
443 #define tx_queue_end(__dev) \
444 &(__dev)->tx[(__dev)->ops->tx_queues]
447 * queue_loop - Loop through the queues within a specific range (HELPER MACRO).
448 * @__entry: Pointer where the current queue entry will be stored in.
449 * @__start: Start queue pointer.
450 * @__end: End queue pointer.
452 * This macro will loop through all queues between &__start and &__end.
454 #define queue_loop(__entry, __start, __end) \
455 for ((__entry) = (__start); \
456 prefetch(&(__entry)[1]), (__entry) != (__end); \
457 (__entry) = &(__entry)[1])
460 * queue_for_each - Loop through all queues
461 * @__dev: Pointer to &struct rt2x00_dev
462 * @__entry: Pointer where the current queue entry will be stored in.
464 * This macro will loop through all available queues.
466 #define queue_for_each(__dev, __entry) \
467 queue_loop(__entry, (__dev)->rx, queue_end(__dev))
470 * tx_queue_for_each - Loop through the TX queues
471 * @__dev: Pointer to &struct rt2x00_dev
472 * @__entry: Pointer where the current queue entry will be stored in.
474 * This macro will loop through all TX related queues excluding
475 * the Beacon and Atim queues.
477 #define tx_queue_for_each(__dev, __entry) \
478 queue_loop(__entry, (__dev)->tx, tx_queue_end(__dev))
481 * txall_queue_for_each - Loop through all TX related queues
482 * @__dev: Pointer to &struct rt2x00_dev
483 * @__entry: Pointer where the current queue entry will be stored in.
485 * This macro will loop through all TX related queues including
486 * the Beacon and Atim queues.
488 #define txall_queue_for_each(__dev, __entry) \
489 queue_loop(__entry, (__dev)->tx, queue_end(__dev))
492 * rt2x00queue_empty - Check if the queue is empty.
493 * @queue: Queue to check if empty.
495 static inline int rt2x00queue_empty(struct data_queue *queue)
497 return queue->length == 0;
501 * rt2x00queue_full - Check if the queue is full.
502 * @queue: Queue to check if full.
504 static inline int rt2x00queue_full(struct data_queue *queue)
506 return queue->length == queue->limit;
510 * rt2x00queue_free - Check the number of available entries in queue.
511 * @queue: Queue to check.
513 static inline int rt2x00queue_available(struct data_queue *queue)
515 return queue->limit - queue->length;
519 * rt2x00queue_threshold - Check if the queue is below threshold
520 * @queue: Queue to check.
522 static inline int rt2x00queue_threshold(struct data_queue *queue)
524 return rt2x00queue_available(queue) < queue->threshold;
528 * _rt2x00_desc_read - Read a word from the hardware descriptor.
529 * @desc: Base descriptor address
530 * @word: Word index from where the descriptor should be read.
531 * @value: Address where the descriptor value should be written into.
533 static inline void _rt2x00_desc_read(__le32 *desc, const u8 word, __le32 *value)
539 * rt2x00_desc_read - Read a word from the hardware descriptor, this
540 * function will take care of the byte ordering.
541 * @desc: Base descriptor address
542 * @word: Word index from where the descriptor should be read.
543 * @value: Address where the descriptor value should be written into.
545 static inline void rt2x00_desc_read(__le32 *desc, const u8 word, u32 *value)
548 _rt2x00_desc_read(desc, word, &tmp);
549 *value = le32_to_cpu(tmp);
553 * rt2x00_desc_write - write a word to the hardware descriptor, this
554 * function will take care of the byte ordering.
555 * @desc: Base descriptor address
556 * @word: Word index from where the descriptor should be written.
557 * @value: Value that should be written into the descriptor.
559 static inline void _rt2x00_desc_write(__le32 *desc, const u8 word, __le32 value)
565 * rt2x00_desc_write - write a word to the hardware descriptor.
566 * @desc: Base descriptor address
567 * @word: Word index from where the descriptor should be written.
568 * @value: Value that should be written into the descriptor.
570 static inline void rt2x00_desc_write(__le32 *desc, const u8 word, u32 value)
572 _rt2x00_desc_write(desc, word, cpu_to_le32(value));
575 #endif /* RT2X00QUEUE_H */