2 Copyright (C) 2004 - 2008 rt2x00 SourceForge Project
3 <http://rt2x00.serialmonkey.com>
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the
17 Free Software Foundation, Inc.,
18 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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 * @signal_plcp: Does the signal field contain the plcp value,
138 * or does it contain the bitrate itself.
139 * @rssi: RSSI of the received frame.
140 * @ofdm: Was frame send with an OFDM rate.
141 * @size: Data size of the received frame.
142 * @flags: MAC80211 receive flags (See &enum mac80211_rx_flags).
143 * @my_bss: Does this frame originate from device's BSS.
145 struct rxdone_entry_desc {
156 * struct txdone_entry_desc: TX done entry descriptor
158 * Summary of information that has been read from the TX frame descriptor
159 * after the device is done with transmission.
161 * @control: Control structure which was used to transmit the frame.
162 * @status: TX status (See &enum tx_status).
163 * @retry: Retry count.
165 struct txdone_entry_desc {
166 struct ieee80211_tx_control *control;
172 * enum txentry_desc_flags: Status flags for TX entry descriptor
174 * @ENTRY_TXD_RTS_FRAME: This frame is a RTS frame.
175 * @ENTRY_TXD_OFDM_RATE: This frame is send out with an OFDM rate.
176 * @ENTRY_TXD_MORE_FRAG: This frame is followed by another fragment.
177 * @ENTRY_TXD_REQ_TIMESTAMP: Require timestamp to be inserted.
178 * @ENTRY_TXD_BURST: This frame belongs to the same burst event.
179 * @ENTRY_TXD_ACK: An ACK is required for this frame.
181 enum txentry_desc_flags {
185 ENTRY_TXD_REQ_TIMESTAMP,
191 * struct txentry_desc: TX Entry descriptor
193 * Summary of information for the frame descriptor before sending a TX frame.
195 * @flags: Descriptor flags (See &enum queue_entry_flags).
196 * @queue: Queue identification (See &enum data_queue_qid).
197 * @length_high: PLCP length high word.
198 * @length_low: PLCP length low word.
199 * @signal: PLCP signal.
200 * @service: PLCP service.
203 * @cw_min: cwmin value.
204 * @cw_max: cwmax value.
206 struct txentry_desc {
209 enum data_queue_qid queue;
223 * enum queue_entry_flags: Status flags for queue entry
225 * @ENTRY_BCN_ASSIGNED: This entry has been assigned to an interface.
226 * As long as this bit is set, this entry may only be touched
227 * through the interface structure.
228 * @ENTRY_OWNER_DEVICE_DATA: This entry is owned by the device for data
229 * transfer (either TX or RX depending on the queue). The entry should
230 * only be touched after the device has signaled it is done with it.
231 * @ENTRY_OWNER_DEVICE_CRYPTO: This entry is owned by the device for data
232 * encryption or decryption. The entry should only be touched after
233 * the device has signaled it is done with it.
236 enum queue_entry_flags {
238 ENTRY_OWNER_DEVICE_DATA,
239 ENTRY_OWNER_DEVICE_CRYPTO,
243 * struct queue_entry: Entry inside the &struct data_queue
245 * @flags: Entry flags, see &enum queue_entry_flags.
246 * @queue: The data queue (&struct data_queue) to which this entry belongs.
247 * @skb: The buffer which is currently being transmitted (for TX queue),
248 * or used to directly recieve data in (for RX queue).
249 * @entry_idx: The entry index number.
250 * @priv_data: Private data belonging to this queue entry. The pointer
251 * points to data specific to a particular driver and queue type.
256 struct data_queue *queue;
260 unsigned int entry_idx;
266 * enum queue_index: Queue index type
268 * @Q_INDEX: Index pointer to the current entry in the queue, if this entry is
269 * owned by the hardware then the queue is considered to be full.
270 * @Q_INDEX_DONE: Index pointer to the next entry which will be completed by
271 * the hardware and for which we need to run the txdone handler. If this
272 * entry is not owned by the hardware the queue is considered to be empty.
273 * @Q_INDEX_CRYPTO: Index pointer to the next entry which encryption/decription
274 * will be completed by the hardware next.
275 * @Q_INDEX_MAX: Keep last, used in &struct data_queue to determine the size
276 * of the index array.
286 * struct data_queue: Data queue
288 * @rt2x00dev: Pointer to main &struct rt2x00dev where this queue belongs to.
289 * @entries: Base address of the &struct queue_entry which are
290 * part of this queue.
291 * @qid: The queue identification, see &enum data_queue_qid.
292 * @lock: Spinlock to protect index handling. Whenever @index, @index_done or
293 * @index_crypt needs to be changed this lock should be grabbed to prevent
294 * index corruption due to concurrency.
295 * @count: Number of frames handled in the queue.
296 * @limit: Maximum number of entries in the queue.
297 * @length: Number of frames in queue.
298 * @index: Index pointers to entry positions in the queue,
299 * use &enum queue_index to get a specific index field.
300 * @aifs: The aifs value for outgoing frames (field ignored in RX queue).
301 * @cw_min: The cw min value for outgoing frames (field ignored in RX queue).
302 * @cw_max: The cw max value for outgoing frames (field ignored in RX queue).
303 * @data_size: Maximum data size for the frames in this queue.
304 * @desc_size: Hardware descriptor size for the data in this queue.
307 struct rt2x00_dev *rt2x00dev;
308 struct queue_entry *entries;
310 enum data_queue_qid qid;
314 unsigned short limit;
315 unsigned short length;
316 unsigned short index[Q_INDEX_MAX];
319 unsigned short cw_min;
320 unsigned short cw_max;
322 unsigned short data_size;
323 unsigned short desc_size;
327 * struct data_queue_desc: Data queue description
329 * The information in this structure is used by drivers
330 * to inform rt2x00lib about the creation of the data queue.
332 * @entry_num: Maximum number of entries for a queue.
333 * @data_size: Maximum data size for the frames in this queue.
334 * @desc_size: Hardware descriptor size for the data in this queue.
335 * @priv_size: Size of per-queue_entry private data.
337 struct data_queue_desc {
338 unsigned short entry_num;
339 unsigned short data_size;
340 unsigned short desc_size;
341 unsigned short priv_size;
345 * queue_end - Return pointer to the last queue (HELPER MACRO).
346 * @__dev: Pointer to &struct rt2x00_dev
348 * Using the base rx pointer and the maximum number of available queues,
349 * this macro will return the address of 1 position beyond the end of the
352 #define queue_end(__dev) \
353 &(__dev)->rx[(__dev)->data_queues]
356 * tx_queue_end - Return pointer to the last TX queue (HELPER MACRO).
357 * @__dev: Pointer to &struct rt2x00_dev
359 * Using the base tx pointer and the maximum number of available TX
360 * queues, this macro will return the address of 1 position beyond
361 * the end of the TX queue array.
363 #define tx_queue_end(__dev) \
364 &(__dev)->tx[(__dev)->hw->queues]
367 * queue_loop - Loop through the queues within a specific range (HELPER MACRO).
368 * @__entry: Pointer where the current queue entry will be stored in.
369 * @__start: Start queue pointer.
370 * @__end: End queue pointer.
372 * This macro will loop through all queues between &__start and &__end.
374 #define queue_loop(__entry, __start, __end) \
375 for ((__entry) = (__start); \
376 prefetch(&(__entry)[1]), (__entry) != (__end); \
377 (__entry) = &(__entry)[1])
380 * queue_for_each - Loop through all queues
381 * @__dev: Pointer to &struct rt2x00_dev
382 * @__entry: Pointer where the current queue entry will be stored in.
384 * This macro will loop through all available queues.
386 #define queue_for_each(__dev, __entry) \
387 queue_loop(__entry, (__dev)->rx, queue_end(__dev))
390 * tx_queue_for_each - Loop through the TX queues
391 * @__dev: Pointer to &struct rt2x00_dev
392 * @__entry: Pointer where the current queue entry will be stored in.
394 * This macro will loop through all TX related queues excluding
395 * the Beacon and Atim queues.
397 #define tx_queue_for_each(__dev, __entry) \
398 queue_loop(__entry, (__dev)->tx, tx_queue_end(__dev))
401 * txall_queue_for_each - Loop through all TX related queues
402 * @__dev: Pointer to &struct rt2x00_dev
403 * @__entry: Pointer where the current queue entry will be stored in.
405 * This macro will loop through all TX related queues including
406 * the Beacon and Atim queues.
408 #define txall_queue_for_each(__dev, __entry) \
409 queue_loop(__entry, (__dev)->tx, queue_end(__dev))
412 * rt2x00queue_empty - Check if the queue is empty.
413 * @queue: Queue to check if empty.
415 static inline int rt2x00queue_empty(struct data_queue *queue)
417 return queue->length == 0;
421 * rt2x00queue_full - Check if the queue is full.
422 * @queue: Queue to check if full.
424 static inline int rt2x00queue_full(struct data_queue *queue)
426 return queue->length == queue->limit;
430 * rt2x00queue_free - Check the number of available entries in queue.
431 * @queue: Queue to check.
433 static inline int rt2x00queue_available(struct data_queue *queue)
435 return queue->limit - queue->length;
439 * rt2x00_desc_read - Read a word from the hardware descriptor.
440 * @desc: Base descriptor address
441 * @word: Word index from where the descriptor should be read.
442 * @value: Address where the descriptor value should be written into.
444 static inline void rt2x00_desc_read(__le32 *desc, const u8 word, u32 *value)
446 *value = le32_to_cpu(desc[word]);
450 * rt2x00_desc_write - wrote a word to the hardware descriptor.
451 * @desc: Base descriptor address
452 * @word: Word index from where the descriptor should be written.
453 * @value: Value that should be written into the descriptor.
455 static inline void rt2x00_desc_write(__le32 *desc, const u8 word, u32 value)
457 desc[word] = cpu_to_le32(value);
460 #endif /* RT2X00QUEUE_H */