2 Copyright (C) 2004 - 2008 rt2x00 SourceForge Project
3 <http://rt2x00.serialmonkey.com>
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12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
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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 * After research it was concluded that 12 entries in a RX and TX
46 * queue would be sufficient. Although this is almost one third of
47 * the amount the legacy driver allocated, the queues aren't getting
48 * filled to the maximum even when working with the maximum rate.
52 #define BEACON_ENTRIES 1
53 #define ATIM_ENTRIES 1
56 * enum data_queue_qid: Queue identification
58 * @QID_AC_BE: AC BE queue
59 * @QID_AC_BK: AC BK queue
60 * @QID_AC_VI: AC VI queue
61 * @QID_AC_VO: AC VO queue
62 * @QID_HCCA: HCCA queue
63 * @QID_MGMT: MGMT queue (prio queue)
65 * @QID_OTHER: None of the above (don't use, only present for completeness)
66 * @QID_BEACON: Beacon queue (value unspecified, don't send it to device)
67 * @QID_ATIM: Atim queue (value unspeficied, don't send it to device)
83 * mac80211_queue_to_qid - Convert mac80211 queue to rt2x00 qid
84 * @queue: mac80211 queue.
86 static inline enum data_queue_qid mac80211_queue_to_qid(unsigned int queue)
88 /* Regular TX queues are mapped directly */
96 * enum skb_frame_desc_flags: Flags for &struct skb_frame_desc
98 * @FRAME_DESC_DRIVER_GENERATED: Frame was generated inside driver
99 * and should not be reported back to mac80211 during txdone.
101 enum skb_frame_desc_flags {
102 FRAME_DESC_DRIVER_GENERATED = 1 << 0,
106 * struct skb_frame_desc: Descriptor information for the skb buffer
108 * This structure is placed over the skb->cb array, this means that
109 * this structure should not exceed the size of that array (48 bytes).
111 * @flags: Frame flags, see &enum skb_frame_desc_flags.
112 * @data: Pointer to data part of frame (Start of ieee80211 header).
113 * @desc: Pointer to descriptor part of the frame.
114 * Note that this pointer could point to something outside
115 * of the scope of the skb->data pointer.
116 * @data_len: Length of the frame data.
117 * @desc_len: Length of the frame descriptor.
118 * @entry: The entry to which this sk buffer belongs.
120 struct skb_frame_desc {
123 unsigned short data_len;
124 unsigned short desc_len;
129 struct queue_entry *entry;
132 static inline struct skb_frame_desc* get_skb_frame_desc(struct sk_buff *skb)
134 BUILD_BUG_ON(sizeof(struct skb_frame_desc) > sizeof(skb->cb));
135 return (struct skb_frame_desc *)&skb->cb[0];
139 * enum rxdone_entry_desc_flags: Flags for &struct rxdone_entry_desc
141 * @RXDONE_SIGNAL_PLCP: Does the signal field contain the plcp value,
142 * or does it contain the bitrate itself.
143 * @RXDONE_MY_BSS: Does this frame originate from device's BSS.
145 enum rxdone_entry_desc_flags {
146 RXDONE_SIGNAL_PLCP = 1 << 0,
147 RXDONE_MY_BSS = 1 << 1,
151 * struct rxdone_entry_desc: RX Entry descriptor
153 * Summary of information that has been read from the RX frame descriptor.
155 * @signal: Signal of the received frame.
156 * @rssi: RSSI of the received frame.
157 * @size: Data size of the received frame.
158 * @flags: MAC80211 receive flags (See &enum mac80211_rx_flags).
159 * @dev_flags: Ralink receive flags (See &enum rxdone_entry_desc_flags).
162 struct rxdone_entry_desc {
171 * enum txdone_entry_desc_flags: Flags for &struct txdone_entry_desc
173 * @TXDONE_UNKNOWN: Hardware could not determine success of transmission.
174 * @TXDONE_SUCCESS: Frame was successfully send
175 * @TXDONE_FAILURE: Frame was not successfully send
176 * @TXDONE_EXCESSIVE_RETRY: In addition to &TXDONE_FAILURE, the
177 * frame transmission failed due to excessive retries.
179 enum txdone_entry_desc_flags {
180 TXDONE_UNKNOWN = 1 << 0,
181 TXDONE_SUCCESS = 1 << 1,
182 TXDONE_FAILURE = 1 << 2,
183 TXDONE_EXCESSIVE_RETRY = 1 << 3,
187 * struct txdone_entry_desc: TX done entry descriptor
189 * Summary of information that has been read from the TX frame descriptor
190 * after the device is done with transmission.
192 * @control: Control structure which was used to transmit the frame.
193 * @flags: TX done flags (See &enum txdone_entry_desc_flags).
194 * @retry: Retry count.
196 struct txdone_entry_desc {
197 struct ieee80211_tx_control *control;
203 * enum txentry_desc_flags: Status flags for TX entry descriptor
205 * @ENTRY_TXD_RTS_FRAME: This frame is a RTS frame.
206 * @ENTRY_TXD_OFDM_RATE: This frame is send out with an OFDM rate.
207 * @ENTRY_TXD_FIRST_FRAGMENT: This is the first frame.
208 * @ENTRY_TXD_MORE_FRAG: This frame is followed by another fragment.
209 * @ENTRY_TXD_REQ_TIMESTAMP: Require timestamp to be inserted.
210 * @ENTRY_TXD_BURST: This frame belongs to the same burst event.
211 * @ENTRY_TXD_ACK: An ACK is required for this frame.
212 * @ENTRY_TXD_RETRY_MODE: When set, the long retry count is used.
214 enum txentry_desc_flags {
217 ENTRY_TXD_FIRST_FRAGMENT,
219 ENTRY_TXD_REQ_TIMESTAMP,
222 ENTRY_TXD_RETRY_MODE,
226 * struct txentry_desc: TX Entry descriptor
228 * Summary of information for the frame descriptor before sending a TX frame.
230 * @flags: Descriptor flags (See &enum queue_entry_flags).
231 * @queue: Queue identification (See &enum data_queue_qid).
232 * @length_high: PLCP length high word.
233 * @length_low: PLCP length low word.
234 * @signal: PLCP signal.
235 * @service: PLCP service.
236 * @retry_limit: Max number of retries.
239 * @cw_min: cwmin value.
240 * @cw_max: cwmax value.
242 struct txentry_desc {
245 enum data_queue_qid queue;
260 * enum queue_entry_flags: Status flags for queue entry
262 * @ENTRY_BCN_ASSIGNED: This entry has been assigned to an interface.
263 * As long as this bit is set, this entry may only be touched
264 * through the interface structure.
265 * @ENTRY_OWNER_DEVICE_DATA: This entry is owned by the device for data
266 * transfer (either TX or RX depending on the queue). The entry should
267 * only be touched after the device has signaled it is done with it.
268 * @ENTRY_OWNER_DEVICE_CRYPTO: This entry is owned by the device for data
269 * encryption or decryption. The entry should only be touched after
270 * the device has signaled it is done with it.
272 enum queue_entry_flags {
274 ENTRY_OWNER_DEVICE_DATA,
275 ENTRY_OWNER_DEVICE_CRYPTO,
279 * struct queue_entry: Entry inside the &struct data_queue
281 * @flags: Entry flags, see &enum queue_entry_flags.
282 * @queue: The data queue (&struct data_queue) to which this entry belongs.
283 * @skb: The buffer which is currently being transmitted (for TX queue),
284 * or used to directly recieve data in (for RX queue).
285 * @entry_idx: The entry index number.
286 * @priv_data: Private data belonging to this queue entry. The pointer
287 * points to data specific to a particular driver and queue type.
292 struct data_queue *queue;
296 unsigned int entry_idx;
302 * enum queue_index: Queue index type
304 * @Q_INDEX: Index pointer to the current entry in the queue, if this entry is
305 * owned by the hardware then the queue is considered to be full.
306 * @Q_INDEX_DONE: Index pointer to the next entry which will be completed by
307 * the hardware and for which we need to run the txdone handler. If this
308 * entry is not owned by the hardware the queue is considered to be empty.
309 * @Q_INDEX_CRYPTO: Index pointer to the next entry which encryption/decription
310 * will be completed by the hardware next.
311 * @Q_INDEX_MAX: Keep last, used in &struct data_queue to determine the size
312 * of the index array.
322 * struct data_queue: Data queue
324 * @rt2x00dev: Pointer to main &struct rt2x00dev where this queue belongs to.
325 * @entries: Base address of the &struct queue_entry which are
326 * part of this queue.
327 * @qid: The queue identification, see &enum data_queue_qid.
328 * @lock: Spinlock to protect index handling. Whenever @index, @index_done or
329 * @index_crypt needs to be changed this lock should be grabbed to prevent
330 * index corruption due to concurrency.
331 * @count: Number of frames handled in the queue.
332 * @limit: Maximum number of entries in the queue.
333 * @length: Number of frames in queue.
334 * @index: Index pointers to entry positions in the queue,
335 * use &enum queue_index to get a specific index field.
336 * @aifs: The aifs value for outgoing frames (field ignored in RX queue).
337 * @cw_min: The cw min value for outgoing frames (field ignored in RX queue).
338 * @cw_max: The cw max value for outgoing frames (field ignored in RX queue).
339 * @data_size: Maximum data size for the frames in this queue.
340 * @desc_size: Hardware descriptor size for the data in this queue.
343 struct rt2x00_dev *rt2x00dev;
344 struct queue_entry *entries;
346 enum data_queue_qid qid;
350 unsigned short limit;
351 unsigned short length;
352 unsigned short index[Q_INDEX_MAX];
355 unsigned short cw_min;
356 unsigned short cw_max;
358 unsigned short data_size;
359 unsigned short desc_size;
363 * struct data_queue_desc: Data queue description
365 * The information in this structure is used by drivers
366 * to inform rt2x00lib about the creation of the data queue.
368 * @entry_num: Maximum number of entries for a queue.
369 * @data_size: Maximum data size for the frames in this queue.
370 * @desc_size: Hardware descriptor size for the data in this queue.
371 * @priv_size: Size of per-queue_entry private data.
373 struct data_queue_desc {
374 unsigned short entry_num;
375 unsigned short data_size;
376 unsigned short desc_size;
377 unsigned short priv_size;
381 * queue_end - Return pointer to the last queue (HELPER MACRO).
382 * @__dev: Pointer to &struct rt2x00_dev
384 * Using the base rx pointer and the maximum number of available queues,
385 * this macro will return the address of 1 position beyond the end of the
388 #define queue_end(__dev) \
389 &(__dev)->rx[(__dev)->data_queues]
392 * tx_queue_end - Return pointer to the last TX queue (HELPER MACRO).
393 * @__dev: Pointer to &struct rt2x00_dev
395 * Using the base tx pointer and the maximum number of available TX
396 * queues, this macro will return the address of 1 position beyond
397 * the end of the TX queue array.
399 #define tx_queue_end(__dev) \
400 &(__dev)->tx[(__dev)->hw->queues]
403 * queue_loop - Loop through the queues within a specific range (HELPER MACRO).
404 * @__entry: Pointer where the current queue entry will be stored in.
405 * @__start: Start queue pointer.
406 * @__end: End queue pointer.
408 * This macro will loop through all queues between &__start and &__end.
410 #define queue_loop(__entry, __start, __end) \
411 for ((__entry) = (__start); \
412 prefetch(&(__entry)[1]), (__entry) != (__end); \
413 (__entry) = &(__entry)[1])
416 * queue_for_each - Loop through all queues
417 * @__dev: Pointer to &struct rt2x00_dev
418 * @__entry: Pointer where the current queue entry will be stored in.
420 * This macro will loop through all available queues.
422 #define queue_for_each(__dev, __entry) \
423 queue_loop(__entry, (__dev)->rx, queue_end(__dev))
426 * tx_queue_for_each - Loop through the TX queues
427 * @__dev: Pointer to &struct rt2x00_dev
428 * @__entry: Pointer where the current queue entry will be stored in.
430 * This macro will loop through all TX related queues excluding
431 * the Beacon and Atim queues.
433 #define tx_queue_for_each(__dev, __entry) \
434 queue_loop(__entry, (__dev)->tx, tx_queue_end(__dev))
437 * txall_queue_for_each - Loop through all TX related queues
438 * @__dev: Pointer to &struct rt2x00_dev
439 * @__entry: Pointer where the current queue entry will be stored in.
441 * This macro will loop through all TX related queues including
442 * the Beacon and Atim queues.
444 #define txall_queue_for_each(__dev, __entry) \
445 queue_loop(__entry, (__dev)->tx, queue_end(__dev))
448 * rt2x00queue_empty - Check if the queue is empty.
449 * @queue: Queue to check if empty.
451 static inline int rt2x00queue_empty(struct data_queue *queue)
453 return queue->length == 0;
457 * rt2x00queue_full - Check if the queue is full.
458 * @queue: Queue to check if full.
460 static inline int rt2x00queue_full(struct data_queue *queue)
462 return queue->length == queue->limit;
466 * rt2x00queue_free - Check the number of available entries in queue.
467 * @queue: Queue to check.
469 static inline int rt2x00queue_available(struct data_queue *queue)
471 return queue->limit - queue->length;
475 * rt2x00_desc_read - Read a word from the hardware descriptor.
476 * @desc: Base descriptor address
477 * @word: Word index from where the descriptor should be read.
478 * @value: Address where the descriptor value should be written into.
480 static inline void rt2x00_desc_read(__le32 *desc, const u8 word, u32 *value)
482 *value = le32_to_cpu(desc[word]);
486 * rt2x00_desc_write - wrote a word to the hardware descriptor.
487 * @desc: Base descriptor address
488 * @word: Word index from where the descriptor should be written.
489 * @value: Value that should be written into the descriptor.
491 static inline void rt2x00_desc_write(__le32 *desc, const u8 word, u32 value)
493 desc[word] = cpu_to_le32(value);
496 #endif /* RT2X00QUEUE_H */