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
70 * enum rt2x00_bcn_queue: Beacon queue index
72 * Start counting with a high offset, this because this enumeration
73 * supplements &enum ieee80211_tx_queue and we should prevent value
76 * @RT2X00_BCN_QUEUE_BEACON: Beacon queue
77 * @RT2X00_BCN_QUEUE_ATIM: Atim queue (sends frame after beacon)
79 enum rt2x00_bcn_queue {
80 RT2X00_BCN_QUEUE_BEACON = 100,
81 RT2X00_BCN_QUEUE_ATIM = 101,
85 * enum skb_frame_desc_flags: Flags for &struct skb_frame_desc
87 * @FRAME_DESC_DRIVER_GENERATED: Frame was generated inside driver
88 * and should not be reported back to mac80211 during txdone.
90 enum skb_frame_desc_flags {
91 FRAME_DESC_DRIVER_GENERATED = 1 << 0,
95 * struct skb_frame_desc: Descriptor information for the skb buffer
97 * This structure is placed over the skb->cb array, this means that
98 * this structure should not exceed the size of that array (48 bytes).
100 * @flags: Frame flags, see &enum skb_frame_desc_flags.
101 * @frame_type: Frame type, see &enum rt2x00_dump_type.
102 * @data: Pointer to data part of frame (Start of ieee80211 header).
103 * @desc: Pointer to descriptor part of the frame.
104 * Note that this pointer could point to something outside
105 * of the scope of the skb->data pointer.
106 * @data_len: Length of the frame data.
107 * @desc_len: Length of the frame descriptor.
109 * @entry: The entry to which this sk buffer belongs.
111 struct skb_frame_desc {
114 unsigned int frame_type;
119 unsigned int data_len;
120 unsigned int desc_len;
122 struct queue_entry *entry;
125 static inline struct skb_frame_desc* get_skb_frame_desc(struct sk_buff *skb)
127 BUILD_BUG_ON(sizeof(struct skb_frame_desc) > sizeof(skb->cb));
128 return (struct skb_frame_desc *)&skb->cb[0];
132 * struct rxdone_entry_desc: RX Entry descriptor
134 * Summary of information that has been read from the RX frame descriptor.
136 * @signal: Signal of the received frame.
137 * @rssi: RSSI of the received frame.
138 * @ofdm: Was frame send with an OFDM rate.
139 * @size: Data size of the received frame.
140 * @flags: MAC80211 receive flags (See &enum mac80211_rx_flags).
141 * @my_bss: Does this frame originate from device's BSS.
143 struct rxdone_entry_desc {
153 * struct txdone_entry_desc: TX done entry descriptor
155 * Summary of information that has been read from the TX frame descriptor
156 * after the device is done with transmission.
158 * @control: Control structure which was used to transmit the frame.
159 * @status: TX status (See &enum tx_status).
160 * @retry: Retry count.
162 struct txdone_entry_desc {
163 struct ieee80211_tx_control *control;
169 * enum txentry_desc_flags: Status flags for TX entry descriptor
171 * @ENTRY_TXD_RTS_FRAME: This frame is a RTS frame.
172 * @ENTRY_TXD_OFDM_RATE: This frame is send out with an OFDM rate.
173 * @ENTRY_TXD_MORE_FRAG: This frame is followed by another fragment.
174 * @ENTRY_TXD_REQ_TIMESTAMP: Require timestamp to be inserted.
175 * @ENTRY_TXD_BURST: This frame belongs to the same burst event.
176 * @ENTRY_TXD_ACK: An ACK is required for this frame.
178 enum txentry_desc_flags {
182 ENTRY_TXD_REQ_TIMESTAMP,
188 * struct txentry_desc: TX Entry descriptor
190 * Summary of information for the frame descriptor before sending a TX frame.
192 * @flags: Descriptor flags (See &enum queue_entry_flags).
193 * @queue: Queue identification (See &enum data_queue_qid).
194 * @length_high: PLCP length high word.
195 * @length_low: PLCP length low word.
196 * @signal: PLCP signal.
197 * @service: PLCP service.
200 * @cw_min: cwmin value.
201 * @cw_max: cwmax value.
203 struct txentry_desc {
206 enum data_queue_qid queue;
220 * enum queue_entry_flags: Status flags for queue entry
222 * @ENTRY_BCN_ASSIGNED: This entry has been assigned to an interface.
223 * As long as this bit is set, this entry may only be touched
224 * through the interface structure.
225 * @ENTRY_OWNER_DEVICE_DATA: This entry is owned by the device for data
226 * transfer (either TX or RX depending on the queue). The entry should
227 * only be touched after the device has signaled it is done with it.
228 * @ENTRY_OWNER_DEVICE_CRYPTO: This entry is owned by the device for data
229 * encryption or decryption. The entry should only be touched after
230 * the device has signaled it is done with it.
233 enum queue_entry_flags {
235 ENTRY_OWNER_DEVICE_DATA,
236 ENTRY_OWNER_DEVICE_CRYPTO,
240 * struct queue_entry: Entry inside the &struct data_queue
242 * @flags: Entry flags, see &enum queue_entry_flags.
243 * @queue: The data queue (&struct data_queue) to which this entry belongs.
244 * @skb: The buffer which is currently being transmitted (for TX queue),
245 * or used to directly recieve data in (for RX queue).
246 * @entry_idx: The entry index number.
247 * @priv_data: Private data belonging to this queue entry. The pointer
248 * points to data specific to a particular driver and queue type.
253 struct data_queue *queue;
257 unsigned int entry_idx;
263 * enum queue_index: Queue index type
265 * @Q_INDEX: Index pointer to the current entry in the queue, if this entry is
266 * owned by the hardware then the queue is considered to be full.
267 * @Q_INDEX_DONE: Index pointer to the next entry which will be completed by
268 * the hardware and for which we need to run the txdone handler. If this
269 * entry is not owned by the hardware the queue is considered to be empty.
270 * @Q_INDEX_CRYPTO: Index pointer to the next entry which encryption/decription
271 * will be completed by the hardware next.
272 * @Q_INDEX_MAX: Keep last, used in &struct data_queue to determine the size
273 * of the index array.
283 * struct data_queue: Data queue
285 * @rt2x00dev: Pointer to main &struct rt2x00dev where this queue belongs to.
286 * @entries: Base address of the &struct queue_entry which are
287 * part of this queue.
288 * @qid: The queue identification, see &enum data_queue_qid.
289 * @lock: Spinlock to protect index handling. Whenever @index, @index_done or
290 * @index_crypt needs to be changed this lock should be grabbed to prevent
291 * index corruption due to concurrency.
292 * @count: Number of frames handled in the queue.
293 * @limit: Maximum number of entries in the queue.
294 * @length: Number of frames in queue.
295 * @index: Index pointers to entry positions in the queue,
296 * use &enum queue_index to get a specific index field.
297 * @aifs: The aifs value for outgoing frames (field ignored in RX queue).
298 * @cw_min: The cw min value for outgoing frames (field ignored in RX queue).
299 * @cw_max: The cw max value for outgoing frames (field ignored in RX queue).
300 * @data_size: Maximum data size for the frames in this queue.
301 * @desc_size: Hardware descriptor size for the data in this queue.
304 struct rt2x00_dev *rt2x00dev;
305 struct queue_entry *entries;
307 enum data_queue_qid qid;
311 unsigned short limit;
312 unsigned short length;
313 unsigned short index[Q_INDEX_MAX];
316 unsigned short cw_min;
317 unsigned short cw_max;
319 unsigned short data_size;
320 unsigned short desc_size;
324 * struct data_queue_desc: Data queue description
326 * The information in this structure is used by drivers
327 * to inform rt2x00lib about the creation of the data queue.
329 * @entry_num: Maximum number of entries for a queue.
330 * @data_size: Maximum data size for the frames in this queue.
331 * @desc_size: Hardware descriptor size for the data in this queue.
332 * @priv_size: Size of per-queue_entry private data.
334 struct data_queue_desc {
335 unsigned short entry_num;
336 unsigned short data_size;
337 unsigned short desc_size;
338 unsigned short priv_size;
342 * queue_end - Return pointer to the last queue (HELPER MACRO).
343 * @__dev: Pointer to &struct rt2x00_dev
345 * Using the base rx pointer and the maximum number of available queues,
346 * this macro will return the address of 1 position beyond the end of the
349 #define queue_end(__dev) \
350 &(__dev)->rx[(__dev)->data_queues]
353 * tx_queue_end - Return pointer to the last TX queue (HELPER MACRO).
354 * @__dev: Pointer to &struct rt2x00_dev
356 * Using the base tx pointer and the maximum number of available TX
357 * queues, this macro will return the address of 1 position beyond
358 * the end of the TX queue array.
360 #define tx_queue_end(__dev) \
361 &(__dev)->tx[(__dev)->hw->queues]
364 * queue_loop - Loop through the queues within a specific range (HELPER MACRO).
365 * @__entry: Pointer where the current queue entry will be stored in.
366 * @__start: Start queue pointer.
367 * @__end: End queue pointer.
369 * This macro will loop through all queues between &__start and &__end.
371 #define queue_loop(__entry, __start, __end) \
372 for ((__entry) = (__start); \
373 prefetch(&(__entry)[1]), (__entry) != (__end); \
374 (__entry) = &(__entry)[1])
377 * queue_for_each - Loop through all queues
378 * @__dev: Pointer to &struct rt2x00_dev
379 * @__entry: Pointer where the current queue entry will be stored in.
381 * This macro will loop through all available queues.
383 #define queue_for_each(__dev, __entry) \
384 queue_loop(__entry, (__dev)->rx, queue_end(__dev))
387 * tx_queue_for_each - Loop through the TX queues
388 * @__dev: Pointer to &struct rt2x00_dev
389 * @__entry: Pointer where the current queue entry will be stored in.
391 * This macro will loop through all TX related queues excluding
392 * the Beacon and Atim queues.
394 #define tx_queue_for_each(__dev, __entry) \
395 queue_loop(__entry, (__dev)->tx, tx_queue_end(__dev))
398 * txall_queue_for_each - Loop through all TX related queues
399 * @__dev: Pointer to &struct rt2x00_dev
400 * @__entry: Pointer where the current queue entry will be stored in.
402 * This macro will loop through all TX related queues including
403 * the Beacon and Atim queues.
405 #define txall_queue_for_each(__dev, __entry) \
406 queue_loop(__entry, (__dev)->tx, queue_end(__dev))
409 * rt2x00queue_empty - Check if the queue is empty.
410 * @queue: Queue to check if empty.
412 static inline int rt2x00queue_empty(struct data_queue *queue)
414 return queue->length == 0;
418 * rt2x00queue_full - Check if the queue is full.
419 * @queue: Queue to check if full.
421 static inline int rt2x00queue_full(struct data_queue *queue)
423 return queue->length == queue->limit;
427 * rt2x00queue_free - Check the number of available entries in queue.
428 * @queue: Queue to check.
430 static inline int rt2x00queue_available(struct data_queue *queue)
432 return queue->limit - queue->length;
436 * rt2x00_desc_read - Read a word from the hardware descriptor.
437 * @desc: Base descriptor address
438 * @word: Word index from where the descriptor should be read.
439 * @value: Address where the descriptor value should be written into.
441 static inline void rt2x00_desc_read(__le32 *desc, const u8 word, u32 *value)
443 *value = le32_to_cpu(desc[word]);
447 * rt2x00_desc_write - wrote a word to the hardware descriptor.
448 * @desc: Base descriptor address
449 * @word: Word index from where the descriptor should be written.
450 * @value: Value that should be written into the descriptor.
452 static inline void rt2x00_desc_write(__le32 *desc, const u8 word, u32 value)
454 desc[word] = cpu_to_le32(value);
457 #endif /* RT2X00QUEUE_H */