2 Copyright (C) 2004 - 2008 rt2x00 SourceForge Project
3 <http://rt2x00.serialmonkey.com>
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6 it under the terms of the GNU General Public License as published by
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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 * enum skb_frame_desc_flags: Flags for &struct skb_frame_desc
86 enum skb_frame_desc_flags {
87 SKBDESC_DMA_MAPPED_RX = (1 << 0),
88 SKBDESC_DMA_MAPPED_TX = (1 << 1),
92 * struct skb_frame_desc: Descriptor information for the skb buffer
94 * This structure is placed over the driver_data array, this means that
95 * this structure should not exceed the size of that array (40 bytes).
97 * @flags: Frame flags, see &enum skb_frame_desc_flags.
98 * @desc_len: Length of the frame descriptor.
99 * @desc: Pointer to descriptor part of the frame.
100 * Note that this pointer could point to something outside
101 * of the scope of the skb->data pointer.
102 * @skb_dma: (PCI-only) the DMA address associated with the sk buffer.
103 * @entry: The entry to which this sk buffer belongs.
105 struct skb_frame_desc {
108 unsigned int desc_len;
113 struct queue_entry *entry;
117 * get_skb_frame_desc - Obtain the rt2x00 frame descriptor from a sk_buff.
118 * @skb: &struct sk_buff from where we obtain the &struct skb_frame_desc
120 static inline struct skb_frame_desc* get_skb_frame_desc(struct sk_buff *skb)
122 BUILD_BUG_ON(sizeof(struct skb_frame_desc) >
123 IEEE80211_TX_INFO_DRIVER_DATA_SIZE);
124 return (struct skb_frame_desc *)&IEEE80211_SKB_CB(skb)->driver_data;
128 * enum rxdone_entry_desc_flags: Flags for &struct rxdone_entry_desc
130 * @RXDONE_SIGNAL_PLCP: Does the signal field contain the plcp value,
131 * or does it contain the bitrate itself.
132 * @RXDONE_MY_BSS: Does this frame originate from device's BSS.
134 enum rxdone_entry_desc_flags {
135 RXDONE_SIGNAL_PLCP = 1 << 0,
136 RXDONE_MY_BSS = 1 << 1,
140 * struct rxdone_entry_desc: RX Entry descriptor
142 * Summary of information that has been read from the RX frame descriptor.
144 * @signal: Signal of the received frame.
145 * @rssi: RSSI of the received frame.
146 * @size: Data size of the received frame.
147 * @flags: MAC80211 receive flags (See &enum mac80211_rx_flags).
148 * @dev_flags: Ralink receive flags (See &enum rxdone_entry_desc_flags).
151 struct rxdone_entry_desc {
160 * enum txdone_entry_desc_flags: Flags for &struct txdone_entry_desc
162 * @TXDONE_UNKNOWN: Hardware could not determine success of transmission.
163 * @TXDONE_SUCCESS: Frame was successfully send
164 * @TXDONE_FAILURE: Frame was not successfully send
165 * @TXDONE_EXCESSIVE_RETRY: In addition to &TXDONE_FAILURE, the
166 * frame transmission failed due to excessive retries.
168 enum txdone_entry_desc_flags {
169 TXDONE_UNKNOWN = 1 << 0,
170 TXDONE_SUCCESS = 1 << 1,
171 TXDONE_FAILURE = 1 << 2,
172 TXDONE_EXCESSIVE_RETRY = 1 << 3,
176 * struct txdone_entry_desc: TX done entry descriptor
178 * Summary of information that has been read from the TX frame descriptor
179 * after the device is done with transmission.
181 * @flags: TX done flags (See &enum txdone_entry_desc_flags).
182 * @retry: Retry count.
184 struct txdone_entry_desc {
190 * enum txentry_desc_flags: Status flags for TX entry descriptor
192 * @ENTRY_TXD_RTS_FRAME: This frame is a RTS frame.
193 * @ENTRY_TXD_CTS_FRAME: This frame is a CTS-to-self frame.
194 * @ENTRY_TXD_OFDM_RATE: This frame is send out with an OFDM rate.
195 * @ENTRY_TXD_FIRST_FRAGMENT: This is the first frame.
196 * @ENTRY_TXD_MORE_FRAG: This frame is followed by another fragment.
197 * @ENTRY_TXD_REQ_TIMESTAMP: Require timestamp to be inserted.
198 * @ENTRY_TXD_BURST: This frame belongs to the same burst event.
199 * @ENTRY_TXD_ACK: An ACK is required for this frame.
200 * @ENTRY_TXD_RETRY_MODE: When set, the long retry count is used.
202 enum txentry_desc_flags {
206 ENTRY_TXD_FIRST_FRAGMENT,
208 ENTRY_TXD_REQ_TIMESTAMP,
211 ENTRY_TXD_RETRY_MODE,
215 * struct txentry_desc: TX Entry descriptor
217 * Summary of information for the frame descriptor before sending a TX frame.
219 * @flags: Descriptor flags (See &enum queue_entry_flags).
220 * @queue: Queue identification (See &enum data_queue_qid).
221 * @length_high: PLCP length high word.
222 * @length_low: PLCP length low word.
223 * @signal: PLCP signal.
224 * @service: PLCP service.
225 * @retry_limit: Max number of retries.
228 * @cw_min: cwmin value.
229 * @cw_max: cwmax value.
231 struct txentry_desc {
234 enum data_queue_qid queue;
249 * enum queue_entry_flags: Status flags for queue entry
251 * @ENTRY_BCN_ASSIGNED: This entry has been assigned to an interface.
252 * As long as this bit is set, this entry may only be touched
253 * through the interface structure.
254 * @ENTRY_OWNER_DEVICE_DATA: This entry is owned by the device for data
255 * transfer (either TX or RX depending on the queue). The entry should
256 * only be touched after the device has signaled it is done with it.
257 * @ENTRY_OWNER_DEVICE_CRYPTO: This entry is owned by the device for data
258 * encryption or decryption. The entry should only be touched after
259 * the device has signaled it is done with it.
260 * @ENTRY_DATA_PENDING: This entry contains a valid frame and is waiting
261 * for the signal to start sending.
263 enum queue_entry_flags {
265 ENTRY_OWNER_DEVICE_DATA,
266 ENTRY_OWNER_DEVICE_CRYPTO,
271 * struct queue_entry: Entry inside the &struct data_queue
273 * @flags: Entry flags, see &enum queue_entry_flags.
274 * @queue: The data queue (&struct data_queue) to which this entry belongs.
275 * @skb: The buffer which is currently being transmitted (for TX queue),
276 * or used to directly recieve data in (for RX queue).
277 * @entry_idx: The entry index number.
278 * @priv_data: Private data belonging to this queue entry. The pointer
279 * points to data specific to a particular driver and queue type.
284 struct data_queue *queue;
288 unsigned int entry_idx;
294 * enum queue_index: Queue index type
296 * @Q_INDEX: Index pointer to the current entry in the queue, if this entry is
297 * owned by the hardware then the queue is considered to be full.
298 * @Q_INDEX_DONE: Index pointer to the next entry which will be completed by
299 * the hardware and for which we need to run the txdone handler. If this
300 * entry is not owned by the hardware the queue is considered to be empty.
301 * @Q_INDEX_CRYPTO: Index pointer to the next entry which encryption/decription
302 * will be completed by the hardware next.
303 * @Q_INDEX_MAX: Keep last, used in &struct data_queue to determine the size
304 * of the index array.
314 * struct data_queue: Data queue
316 * @rt2x00dev: Pointer to main &struct rt2x00dev where this queue belongs to.
317 * @entries: Base address of the &struct queue_entry which are
318 * part of this queue.
319 * @qid: The queue identification, see &enum data_queue_qid.
320 * @lock: Spinlock to protect index handling. Whenever @index, @index_done or
321 * @index_crypt needs to be changed this lock should be grabbed to prevent
322 * index corruption due to concurrency.
323 * @count: Number of frames handled in the queue.
324 * @limit: Maximum number of entries in the queue.
325 * @threshold: Minimum number of free entries before queue is kicked by force.
326 * @length: Number of frames in queue.
327 * @index: Index pointers to entry positions in the queue,
328 * use &enum queue_index to get a specific index field.
329 * @aifs: The aifs value for outgoing frames (field ignored in RX queue).
330 * @cw_min: The cw min value for outgoing frames (field ignored in RX queue).
331 * @cw_max: The cw max value for outgoing frames (field ignored in RX queue).
332 * @data_size: Maximum data size for the frames in this queue.
333 * @desc_size: Hardware descriptor size for the data in this queue.
336 struct rt2x00_dev *rt2x00dev;
337 struct queue_entry *entries;
339 enum data_queue_qid qid;
343 unsigned short limit;
344 unsigned short threshold;
345 unsigned short length;
346 unsigned short index[Q_INDEX_MAX];
349 unsigned short cw_min;
350 unsigned short cw_max;
352 unsigned short data_size;
353 unsigned short desc_size;
357 * struct data_queue_desc: Data queue description
359 * The information in this structure is used by drivers
360 * to inform rt2x00lib about the creation of the data queue.
362 * @entry_num: Maximum number of entries for a queue.
363 * @data_size: Maximum data size for the frames in this queue.
364 * @desc_size: Hardware descriptor size for the data in this queue.
365 * @priv_size: Size of per-queue_entry private data.
367 struct data_queue_desc {
368 unsigned short entry_num;
369 unsigned short data_size;
370 unsigned short desc_size;
371 unsigned short priv_size;
375 * queue_end - Return pointer to the last queue (HELPER MACRO).
376 * @__dev: Pointer to &struct rt2x00_dev
378 * Using the base rx pointer and the maximum number of available queues,
379 * this macro will return the address of 1 position beyond the end of the
382 #define queue_end(__dev) \
383 &(__dev)->rx[(__dev)->data_queues]
386 * tx_queue_end - Return pointer to the last TX queue (HELPER MACRO).
387 * @__dev: Pointer to &struct rt2x00_dev
389 * Using the base tx pointer and the maximum number of available TX
390 * queues, this macro will return the address of 1 position beyond
391 * the end of the TX queue array.
393 #define tx_queue_end(__dev) \
394 &(__dev)->tx[(__dev)->ops->tx_queues]
397 * queue_loop - Loop through the queues within a specific range (HELPER MACRO).
398 * @__entry: Pointer where the current queue entry will be stored in.
399 * @__start: Start queue pointer.
400 * @__end: End queue pointer.
402 * This macro will loop through all queues between &__start and &__end.
404 #define queue_loop(__entry, __start, __end) \
405 for ((__entry) = (__start); \
406 prefetch(&(__entry)[1]), (__entry) != (__end); \
407 (__entry) = &(__entry)[1])
410 * queue_for_each - Loop through all queues
411 * @__dev: Pointer to &struct rt2x00_dev
412 * @__entry: Pointer where the current queue entry will be stored in.
414 * This macro will loop through all available queues.
416 #define queue_for_each(__dev, __entry) \
417 queue_loop(__entry, (__dev)->rx, queue_end(__dev))
420 * tx_queue_for_each - Loop through the TX queues
421 * @__dev: Pointer to &struct rt2x00_dev
422 * @__entry: Pointer where the current queue entry will be stored in.
424 * This macro will loop through all TX related queues excluding
425 * the Beacon and Atim queues.
427 #define tx_queue_for_each(__dev, __entry) \
428 queue_loop(__entry, (__dev)->tx, tx_queue_end(__dev))
431 * txall_queue_for_each - Loop through all TX related queues
432 * @__dev: Pointer to &struct rt2x00_dev
433 * @__entry: Pointer where the current queue entry will be stored in.
435 * This macro will loop through all TX related queues including
436 * the Beacon and Atim queues.
438 #define txall_queue_for_each(__dev, __entry) \
439 queue_loop(__entry, (__dev)->tx, queue_end(__dev))
442 * rt2x00queue_empty - Check if the queue is empty.
443 * @queue: Queue to check if empty.
445 static inline int rt2x00queue_empty(struct data_queue *queue)
447 return queue->length == 0;
451 * rt2x00queue_full - Check if the queue is full.
452 * @queue: Queue to check if full.
454 static inline int rt2x00queue_full(struct data_queue *queue)
456 return queue->length == queue->limit;
460 * rt2x00queue_free - Check the number of available entries in queue.
461 * @queue: Queue to check.
463 static inline int rt2x00queue_available(struct data_queue *queue)
465 return queue->limit - queue->length;
469 * rt2x00queue_threshold - Check if the queue is below threshold
470 * @queue: Queue to check.
472 static inline int rt2x00queue_threshold(struct data_queue *queue)
474 return rt2x00queue_available(queue) < queue->threshold;
478 * rt2x00_desc_read - Read a word from the hardware descriptor.
479 * @desc: Base descriptor address
480 * @word: Word index from where the descriptor should be read.
481 * @value: Address where the descriptor value should be written into.
483 static inline void rt2x00_desc_read(__le32 *desc, const u8 word, u32 *value)
485 *value = le32_to_cpu(desc[word]);
489 * rt2x00_desc_write - wrote a word to the hardware descriptor.
490 * @desc: Base descriptor address
491 * @word: Word index from where the descriptor should be written.
492 * @value: Value that should be written into the descriptor.
494 static inline void rt2x00_desc_write(__le32 *desc, const u8 word, u32 value)
496 desc[word] = cpu_to_le32(value);
499 #endif /* RT2X00QUEUE_H */