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
91 enum skb_frame_desc_flags {
92 SKBDESC_DMA_MAPPED_RX = (1 << 0),
93 SKBDESC_DMA_MAPPED_TX = (1 << 1),
97 * struct skb_frame_desc: Descriptor information for the skb buffer
99 * This structure is placed over the driver_data array, this means that
100 * this structure should not exceed the size of that array (40 bytes).
102 * @flags: Frame flags, see &enum skb_frame_desc_flags.
103 * @desc_len: Length of the frame descriptor.
104 * @desc: Pointer to descriptor part of the frame.
105 * Note that this pointer could point to something outside
106 * of the scope of the skb->data pointer.
107 * @skb_dma: (PCI-only) the DMA address associated with the sk buffer.
108 * @entry: The entry to which this sk buffer belongs.
110 struct skb_frame_desc {
113 unsigned int desc_len;
118 struct queue_entry *entry;
122 * get_skb_frame_desc - Obtain the rt2x00 frame descriptor from a sk_buff.
123 * @skb: &struct sk_buff from where we obtain the &struct skb_frame_desc
125 static inline struct skb_frame_desc* get_skb_frame_desc(struct sk_buff *skb)
127 BUILD_BUG_ON(sizeof(struct skb_frame_desc) >
128 IEEE80211_TX_INFO_DRIVER_DATA_SIZE);
129 return (struct skb_frame_desc *)&IEEE80211_SKB_CB(skb)->driver_data;
133 * enum rxdone_entry_desc_flags: Flags for &struct rxdone_entry_desc
135 * @RXDONE_SIGNAL_PLCP: Does the signal field contain the plcp value,
136 * or does it contain the bitrate itself.
137 * @RXDONE_MY_BSS: Does this frame originate from device's BSS.
139 enum rxdone_entry_desc_flags {
140 RXDONE_SIGNAL_PLCP = 1 << 0,
141 RXDONE_MY_BSS = 1 << 1,
145 * struct rxdone_entry_desc: RX Entry descriptor
147 * Summary of information that has been read from the RX frame descriptor.
149 * @signal: Signal of the received frame.
150 * @rssi: RSSI of the received frame.
151 * @size: Data size of the received frame.
152 * @flags: MAC80211 receive flags (See &enum mac80211_rx_flags).
153 * @dev_flags: Ralink receive flags (See &enum rxdone_entry_desc_flags).
156 struct rxdone_entry_desc {
165 * enum txdone_entry_desc_flags: Flags for &struct txdone_entry_desc
167 * @TXDONE_UNKNOWN: Hardware could not determine success of transmission.
168 * @TXDONE_SUCCESS: Frame was successfully send
169 * @TXDONE_FAILURE: Frame was not successfully send
170 * @TXDONE_EXCESSIVE_RETRY: In addition to &TXDONE_FAILURE, the
171 * frame transmission failed due to excessive retries.
173 enum txdone_entry_desc_flags {
174 TXDONE_UNKNOWN = 1 << 0,
175 TXDONE_SUCCESS = 1 << 1,
176 TXDONE_FAILURE = 1 << 2,
177 TXDONE_EXCESSIVE_RETRY = 1 << 3,
181 * struct txdone_entry_desc: TX done entry descriptor
183 * Summary of information that has been read from the TX frame descriptor
184 * after the device is done with transmission.
186 * @flags: TX done flags (See &enum txdone_entry_desc_flags).
187 * @retry: Retry count.
189 struct txdone_entry_desc {
195 * enum txentry_desc_flags: Status flags for TX entry descriptor
197 * @ENTRY_TXD_RTS_FRAME: This frame is a RTS frame.
198 * @ENTRY_TXD_CTS_FRAME: This frame is a CTS-to-self frame.
199 * @ENTRY_TXD_OFDM_RATE: This frame is send out with an OFDM rate.
200 * @ENTRY_TXD_FIRST_FRAGMENT: This is the first frame.
201 * @ENTRY_TXD_MORE_FRAG: This frame is followed by another fragment.
202 * @ENTRY_TXD_REQ_TIMESTAMP: Require timestamp to be inserted.
203 * @ENTRY_TXD_BURST: This frame belongs to the same burst event.
204 * @ENTRY_TXD_ACK: An ACK is required for this frame.
205 * @ENTRY_TXD_RETRY_MODE: When set, the long retry count is used.
207 enum txentry_desc_flags {
211 ENTRY_TXD_FIRST_FRAGMENT,
213 ENTRY_TXD_REQ_TIMESTAMP,
216 ENTRY_TXD_RETRY_MODE,
220 * struct txentry_desc: TX Entry descriptor
222 * Summary of information for the frame descriptor before sending a TX frame.
224 * @flags: Descriptor flags (See &enum queue_entry_flags).
225 * @queue: Queue identification (See &enum data_queue_qid).
226 * @length_high: PLCP length high word.
227 * @length_low: PLCP length low word.
228 * @signal: PLCP signal.
229 * @service: PLCP service.
230 * @retry_limit: Max number of retries.
233 * @cw_min: cwmin value.
234 * @cw_max: cwmax value.
236 struct txentry_desc {
239 enum data_queue_qid queue;
254 * enum queue_entry_flags: Status flags for queue entry
256 * @ENTRY_BCN_ASSIGNED: This entry has been assigned to an interface.
257 * As long as this bit is set, this entry may only be touched
258 * through the interface structure.
259 * @ENTRY_OWNER_DEVICE_DATA: This entry is owned by the device for data
260 * transfer (either TX or RX depending on the queue). The entry should
261 * only be touched after the device has signaled it is done with it.
262 * @ENTRY_OWNER_DEVICE_CRYPTO: This entry is owned by the device for data
263 * encryption or decryption. The entry should only be touched after
264 * the device has signaled it is done with it.
265 * @ENTRY_DATA_PENDING: This entry contains a valid frame and is waiting
266 * for the signal to start sending.
268 enum queue_entry_flags {
270 ENTRY_OWNER_DEVICE_DATA,
271 ENTRY_OWNER_DEVICE_CRYPTO,
276 * struct queue_entry: Entry inside the &struct data_queue
278 * @flags: Entry flags, see &enum queue_entry_flags.
279 * @queue: The data queue (&struct data_queue) to which this entry belongs.
280 * @skb: The buffer which is currently being transmitted (for TX queue),
281 * or used to directly recieve data in (for RX queue).
282 * @entry_idx: The entry index number.
283 * @priv_data: Private data belonging to this queue entry. The pointer
284 * points to data specific to a particular driver and queue type.
289 struct data_queue *queue;
293 unsigned int entry_idx;
299 * enum queue_index: Queue index type
301 * @Q_INDEX: Index pointer to the current entry in the queue, if this entry is
302 * owned by the hardware then the queue is considered to be full.
303 * @Q_INDEX_DONE: Index pointer to the next entry which will be completed by
304 * the hardware and for which we need to run the txdone handler. If this
305 * entry is not owned by the hardware the queue is considered to be empty.
306 * @Q_INDEX_CRYPTO: Index pointer to the next entry which encryption/decription
307 * will be completed by the hardware next.
308 * @Q_INDEX_MAX: Keep last, used in &struct data_queue to determine the size
309 * of the index array.
319 * struct data_queue: Data queue
321 * @rt2x00dev: Pointer to main &struct rt2x00dev where this queue belongs to.
322 * @entries: Base address of the &struct queue_entry which are
323 * part of this queue.
324 * @qid: The queue identification, see &enum data_queue_qid.
325 * @lock: Spinlock to protect index handling. Whenever @index, @index_done or
326 * @index_crypt needs to be changed this lock should be grabbed to prevent
327 * index corruption due to concurrency.
328 * @count: Number of frames handled in the queue.
329 * @limit: Maximum number of entries in the queue.
330 * @threshold: Minimum number of free entries before queue is kicked by force.
331 * @length: Number of frames in queue.
332 * @index: Index pointers to entry positions in the queue,
333 * use &enum queue_index to get a specific index field.
334 * @aifs: The aifs value for outgoing frames (field ignored in RX queue).
335 * @cw_min: The cw min value for outgoing frames (field ignored in RX queue).
336 * @cw_max: The cw max value for outgoing frames (field ignored in RX queue).
337 * @data_size: Maximum data size for the frames in this queue.
338 * @desc_size: Hardware descriptor size for the data in this queue.
341 struct rt2x00_dev *rt2x00dev;
342 struct queue_entry *entries;
344 enum data_queue_qid qid;
348 unsigned short limit;
349 unsigned short threshold;
350 unsigned short length;
351 unsigned short index[Q_INDEX_MAX];
354 unsigned short cw_min;
355 unsigned short cw_max;
357 unsigned short data_size;
358 unsigned short desc_size;
362 * struct data_queue_desc: Data queue description
364 * The information in this structure is used by drivers
365 * to inform rt2x00lib about the creation of the data queue.
367 * @entry_num: Maximum number of entries for a queue.
368 * @data_size: Maximum data size for the frames in this queue.
369 * @desc_size: Hardware descriptor size for the data in this queue.
370 * @priv_size: Size of per-queue_entry private data.
372 struct data_queue_desc {
373 unsigned short entry_num;
374 unsigned short data_size;
375 unsigned short desc_size;
376 unsigned short priv_size;
380 * queue_end - Return pointer to the last queue (HELPER MACRO).
381 * @__dev: Pointer to &struct rt2x00_dev
383 * Using the base rx pointer and the maximum number of available queues,
384 * this macro will return the address of 1 position beyond the end of the
387 #define queue_end(__dev) \
388 &(__dev)->rx[(__dev)->data_queues]
391 * tx_queue_end - Return pointer to the last TX queue (HELPER MACRO).
392 * @__dev: Pointer to &struct rt2x00_dev
394 * Using the base tx pointer and the maximum number of available TX
395 * queues, this macro will return the address of 1 position beyond
396 * the end of the TX queue array.
398 #define tx_queue_end(__dev) \
399 &(__dev)->tx[(__dev)->ops->tx_queues]
402 * queue_loop - Loop through the queues within a specific range (HELPER MACRO).
403 * @__entry: Pointer where the current queue entry will be stored in.
404 * @__start: Start queue pointer.
405 * @__end: End queue pointer.
407 * This macro will loop through all queues between &__start and &__end.
409 #define queue_loop(__entry, __start, __end) \
410 for ((__entry) = (__start); \
411 prefetch(&(__entry)[1]), (__entry) != (__end); \
412 (__entry) = &(__entry)[1])
415 * queue_for_each - Loop through all queues
416 * @__dev: Pointer to &struct rt2x00_dev
417 * @__entry: Pointer where the current queue entry will be stored in.
419 * This macro will loop through all available queues.
421 #define queue_for_each(__dev, __entry) \
422 queue_loop(__entry, (__dev)->rx, queue_end(__dev))
425 * tx_queue_for_each - Loop through the TX queues
426 * @__dev: Pointer to &struct rt2x00_dev
427 * @__entry: Pointer where the current queue entry will be stored in.
429 * This macro will loop through all TX related queues excluding
430 * the Beacon and Atim queues.
432 #define tx_queue_for_each(__dev, __entry) \
433 queue_loop(__entry, (__dev)->tx, tx_queue_end(__dev))
436 * txall_queue_for_each - Loop through all TX related queues
437 * @__dev: Pointer to &struct rt2x00_dev
438 * @__entry: Pointer where the current queue entry will be stored in.
440 * This macro will loop through all TX related queues including
441 * the Beacon and Atim queues.
443 #define txall_queue_for_each(__dev, __entry) \
444 queue_loop(__entry, (__dev)->tx, queue_end(__dev))
447 * rt2x00queue_empty - Check if the queue is empty.
448 * @queue: Queue to check if empty.
450 static inline int rt2x00queue_empty(struct data_queue *queue)
452 return queue->length == 0;
456 * rt2x00queue_full - Check if the queue is full.
457 * @queue: Queue to check if full.
459 static inline int rt2x00queue_full(struct data_queue *queue)
461 return queue->length == queue->limit;
465 * rt2x00queue_free - Check the number of available entries in queue.
466 * @queue: Queue to check.
468 static inline int rt2x00queue_available(struct data_queue *queue)
470 return queue->limit - queue->length;
474 * rt2x00queue_threshold - Check if the queue is below threshold
475 * @queue: Queue to check.
477 static inline int rt2x00queue_threshold(struct data_queue *queue)
479 return rt2x00queue_available(queue) < queue->threshold;
483 * rt2x00_desc_read - Read a word from the hardware descriptor.
484 * @desc: Base descriptor address
485 * @word: Word index from where the descriptor should be read.
486 * @value: Address where the descriptor value should be written into.
488 static inline void rt2x00_desc_read(__le32 *desc, const u8 word, u32 *value)
490 *value = le32_to_cpu(desc[word]);
494 * rt2x00_desc_write - wrote a word to the hardware descriptor.
495 * @desc: Base descriptor address
496 * @word: Word index from where the descriptor should be written.
497 * @value: Value that should be written into the descriptor.
499 static inline void rt2x00_desc_write(__le32 *desc, const u8 word, u32 value)
501 desc[word] = cpu_to_le32(value);
504 #endif /* RT2X00QUEUE_H */