1/*
2 * Copyright (c) 2004-2008 Reyk Floeter <reyk@openbsd.org>
3 * Copyright (c) 2006-2008 Nick Kossifidis <mickflemm@gmail.com>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 *
17 */
18
19/********************************************\
20Queue Control Unit, DCF Control Unit Functions
21\********************************************/
22
23#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24
25#include "ath5k.h"
26#include "reg.h"
27#include "debug.h"
28#include <linux/log2.h>
29
30/**
31 * DOC: Queue Control Unit (QCU)/DCF Control Unit (DCU) functions
32 *
33 * Here we setup parameters for the 12 available TX queues. Note that
34 * on the various registers we can usually only map the first 10 of them so
35 * basically we have 10 queues to play with. Each queue has a matching
36 * QCU that controls when the queue will get triggered and multiple QCUs
37 * can be mapped to a single DCU that controls the various DFS parameters
38 * for the various queues. In our setup we have a 1:1 mapping between QCUs
39 * and DCUs allowing us to have different DFS settings for each queue.
40 *
41 * When a frame goes into a TX queue, QCU decides when it'll trigger a
42 * transmission based on various criteria (such as how many data we have inside
43 * it's buffer or -if it's a beacon queue- if it's time to fire up the queue
44 * based on TSF etc), DCU adds backoff, IFSes etc and then a scheduler
45 * (arbitrator) decides the priority of each QCU based on it's configuration
46 * (e.g. beacons are always transmitted when they leave DCU bypassing all other
47 * frames from other queues waiting to be transmitted). After a frame leaves
48 * the DCU it goes to PCU for further processing and then to PHY for
49 * the actual transmission.
50 */
51
52
53/******************\
54* Helper functions *
55\******************/
56
57/**
58 * ath5k_hw_num_tx_pending() - Get number of pending frames for a  given queue
59 * @ah: The &struct ath5k_hw
60 * @queue: One of enum ath5k_tx_queue_id
61 */
62u32
63ath5k_hw_num_tx_pending(struct ath5k_hw *ah, unsigned int queue)
64{
65	u32 pending;
66	AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num);
67
68	/* Return if queue is declared inactive */
69	if (ah->ah_txq[queue].tqi_type == AR5K_TX_QUEUE_INACTIVE)
70		return false;
71
72	/* XXX: How about AR5K_CFG_TXCNT ? */
73	if (ah->ah_version == AR5K_AR5210)
74		return false;
75
76	pending = ath5k_hw_reg_read(ah, AR5K_QUEUE_STATUS(queue));
77	pending &= AR5K_QCU_STS_FRMPENDCNT;
78
79	/* It's possible to have no frames pending even if TXE
80	 * is set. To indicate that q has not stopped return
81	 * true */
82	if (!pending && AR5K_REG_READ_Q(ah, AR5K_QCU_TXE, queue))
83		return true;
84
85	return pending;
86}
87
88/**
89 * ath5k_hw_release_tx_queue() - Set a transmit queue inactive
90 * @ah: The &struct ath5k_hw
91 * @queue: One of enum ath5k_tx_queue_id
92 */
93void
94ath5k_hw_release_tx_queue(struct ath5k_hw *ah, unsigned int queue)
95{
96	if (WARN_ON(queue >= ah->ah_capabilities.cap_queues.q_tx_num))
97		return;
98
99	/* This queue will be skipped in further operations */
100	ah->ah_txq[queue].tqi_type = AR5K_TX_QUEUE_INACTIVE;
101	/*For SIMR setup*/
102	AR5K_Q_DISABLE_BITS(ah->ah_txq_status, queue);
103}
104
105/**
106 * ath5k_cw_validate() - Make sure the given cw is valid
107 * @cw_req: The contention window value to check
108 *
109 * Make sure cw is a power of 2 minus 1 and smaller than 1024
110 */
111static u16
112ath5k_cw_validate(u16 cw_req)
113{
114	cw_req = min(cw_req, (u16)1023);
115
116	/* Check if cw_req + 1 a power of 2 */
117	if (is_power_of_2(cw_req + 1))
118		return cw_req;
119
120	/* Check if cw_req is a power of 2 */
121	if (is_power_of_2(cw_req))
122		return cw_req - 1;
123
124	/* If none of the above is correct
125	 * find the closest power of 2 */
126	cw_req = (u16) roundup_pow_of_two(cw_req) - 1;
127
128	return cw_req;
129}
130
131/**
132 * ath5k_hw_get_tx_queueprops() - Get properties for a transmit queue
133 * @ah: The &struct ath5k_hw
134 * @queue: One of enum ath5k_tx_queue_id
135 * @queue_info: The &struct ath5k_txq_info to fill
136 */
137int
138ath5k_hw_get_tx_queueprops(struct ath5k_hw *ah, int queue,
139		struct ath5k_txq_info *queue_info)
140{
141	memcpy(queue_info, &ah->ah_txq[queue], sizeof(struct ath5k_txq_info));
142	return 0;
143}
144
145/**
146 * ath5k_hw_set_tx_queueprops() - Set properties for a transmit queue
147 * @ah: The &struct ath5k_hw
148 * @queue: One of enum ath5k_tx_queue_id
149 * @qinfo: The &struct ath5k_txq_info to use
150 *
151 * Returns 0 on success or -EIO if queue is inactive
152 */
153int
154ath5k_hw_set_tx_queueprops(struct ath5k_hw *ah, int queue,
155				const struct ath5k_txq_info *qinfo)
156{
157	struct ath5k_txq_info *qi;
158
159	AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num);
160
161	qi = &ah->ah_txq[queue];
162
163	if (qi->tqi_type == AR5K_TX_QUEUE_INACTIVE)
164		return -EIO;
165
166	/* copy and validate values */
167	qi->tqi_type = qinfo->tqi_type;
168	qi->tqi_subtype = qinfo->tqi_subtype;
169	qi->tqi_flags = qinfo->tqi_flags;
170	/*
171	 * According to the docs: Although the AIFS field is 8 bit wide,
172	 * the maximum supported value is 0xFC. Setting it higher than that
173	 * will cause the DCU to hang.
174	 */
175	qi->tqi_aifs = min(qinfo->tqi_aifs, (u8)0xFC);
176	qi->tqi_cw_min = ath5k_cw_validate(qinfo->tqi_cw_min);
177	qi->tqi_cw_max = ath5k_cw_validate(qinfo->tqi_cw_max);
178	qi->tqi_cbr_period = qinfo->tqi_cbr_period;
179	qi->tqi_cbr_overflow_limit = qinfo->tqi_cbr_overflow_limit;
180	qi->tqi_burst_time = qinfo->tqi_burst_time;
181	qi->tqi_ready_time = qinfo->tqi_ready_time;
182
183	/*XXX: Is this supported on 5210 ?*/
184	/*XXX: Is this correct for AR5K_WME_AC_VI,VO ???*/
185	if ((qinfo->tqi_type == AR5K_TX_QUEUE_DATA &&
186		((qinfo->tqi_subtype == AR5K_WME_AC_VI) ||
187		 (qinfo->tqi_subtype == AR5K_WME_AC_VO))) ||
188	     qinfo->tqi_type == AR5K_TX_QUEUE_UAPSD)
189		qi->tqi_flags |= AR5K_TXQ_FLAG_POST_FR_BKOFF_DIS;
190
191	return 0;
192}
193
194/**
195 * ath5k_hw_setup_tx_queue() - Initialize a transmit queue
196 * @ah: The &struct ath5k_hw
197 * @queue_type: One of enum ath5k_tx_queue
198 * @queue_info: The &struct ath5k_txq_info to use
199 *
200 * Returns 0 on success, -EINVAL on invalid arguments
201 */
202int
203ath5k_hw_setup_tx_queue(struct ath5k_hw *ah, enum ath5k_tx_queue queue_type,
204		struct ath5k_txq_info *queue_info)
205{
206	unsigned int queue;
207	int ret;
208
209	/*
210	 * Get queue by type
211	 */
212	/* 5210 only has 2 queues */
213	if (ah->ah_capabilities.cap_queues.q_tx_num == 2) {
214		switch (queue_type) {
215		case AR5K_TX_QUEUE_DATA:
216			queue = AR5K_TX_QUEUE_ID_NOQCU_DATA;
217			break;
218		case AR5K_TX_QUEUE_BEACON:
219		case AR5K_TX_QUEUE_CAB:
220			queue = AR5K_TX_QUEUE_ID_NOQCU_BEACON;
221			break;
222		default:
223			return -EINVAL;
224		}
225	} else {
226		switch (queue_type) {
227		case AR5K_TX_QUEUE_DATA:
228			queue = queue_info->tqi_subtype;
229			break;
230		case AR5K_TX_QUEUE_UAPSD:
231			queue = AR5K_TX_QUEUE_ID_UAPSD;
232			break;
233		case AR5K_TX_QUEUE_BEACON:
234			queue = AR5K_TX_QUEUE_ID_BEACON;
235			break;
236		case AR5K_TX_QUEUE_CAB:
237			queue = AR5K_TX_QUEUE_ID_CAB;
238			break;
239		default:
240			return -EINVAL;
241		}
242	}
243
244	/*
245	 * Setup internal queue structure
246	 */
247	memset(&ah->ah_txq[queue], 0, sizeof(struct ath5k_txq_info));
248	ah->ah_txq[queue].tqi_type = queue_type;
249
250	if (queue_info != NULL) {
251		queue_info->tqi_type = queue_type;
252		ret = ath5k_hw_set_tx_queueprops(ah, queue, queue_info);
253		if (ret)
254			return ret;
255	}
256
257	/*
258	 * We use ah_txq_status to hold a temp value for
259	 * the Secondary interrupt mask registers on 5211+
260	 * check out ath5k_hw_reset_tx_queue
261	 */
262	AR5K_Q_ENABLE_BITS(ah->ah_txq_status, queue);
263
264	return queue;
265}
266
267
268/*******************************\
269* Single QCU/DCU initialization *
270\*******************************/
271
272/**
273 * ath5k_hw_set_tx_retry_limits() - Set tx retry limits on DCU
274 * @ah: The &struct ath5k_hw
275 * @queue: One of enum ath5k_tx_queue_id
276 *
277 * This function is used when initializing a queue, to set
278 * retry limits based on ah->ah_retry_* and the chipset used.
279 */
280void
281ath5k_hw_set_tx_retry_limits(struct ath5k_hw *ah,
282				  unsigned int queue)
283{
284	/* Single data queue on AR5210 */
285	if (ah->ah_version == AR5K_AR5210) {
286		struct ath5k_txq_info *tq = &ah->ah_txq[queue];
287
288		if (queue > 0)
289			return;
290
291		ath5k_hw_reg_write(ah,
292			(tq->tqi_cw_min << AR5K_NODCU_RETRY_LMT_CW_MIN_S)
293			| AR5K_REG_SM(ah->ah_retry_long,
294				      AR5K_NODCU_RETRY_LMT_SLG_RETRY)
295			| AR5K_REG_SM(ah->ah_retry_short,
296				      AR5K_NODCU_RETRY_LMT_SSH_RETRY)
297			| AR5K_REG_SM(ah->ah_retry_long,
298				      AR5K_NODCU_RETRY_LMT_LG_RETRY)
299			| AR5K_REG_SM(ah->ah_retry_short,
300				      AR5K_NODCU_RETRY_LMT_SH_RETRY),
301			AR5K_NODCU_RETRY_LMT);
302	/* DCU on AR5211+ */
303	} else {
304		ath5k_hw_reg_write(ah,
305			AR5K_REG_SM(ah->ah_retry_long,
306				    AR5K_DCU_RETRY_LMT_RTS)
307			| AR5K_REG_SM(ah->ah_retry_long,
308				      AR5K_DCU_RETRY_LMT_STA_RTS)
309			| AR5K_REG_SM(max(ah->ah_retry_long, ah->ah_retry_short),
310				      AR5K_DCU_RETRY_LMT_STA_DATA),
311			AR5K_QUEUE_DFS_RETRY_LIMIT(queue));
312	}
313}
314
315/**
316 * ath5k_hw_reset_tx_queue() - Initialize a single hw queue
317 * @ah: The &struct ath5k_hw
318 * @queue: One of enum ath5k_tx_queue_id
319 *
320 * Set DCF properties for the given transmit queue on DCU
321 * and configures all queue-specific parameters.
322 */
323int
324ath5k_hw_reset_tx_queue(struct ath5k_hw *ah, unsigned int queue)
325{
326	struct ath5k_txq_info *tq = &ah->ah_txq[queue];
327
328	AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num);
329
330	tq = &ah->ah_txq[queue];
331
332	/* Skip if queue inactive or if we are on AR5210
333	 * that doesn't have QCU/DCU */
334	if ((ah->ah_version == AR5K_AR5210) ||
335	(tq->tqi_type == AR5K_TX_QUEUE_INACTIVE))
336		return 0;
337
338	/*
339	 * Set contention window (cw_min/cw_max)
340	 * and arbitrated interframe space (aifs)...
341	 */
342	ath5k_hw_reg_write(ah,
343		AR5K_REG_SM(tq->tqi_cw_min, AR5K_DCU_LCL_IFS_CW_MIN) |
344		AR5K_REG_SM(tq->tqi_cw_max, AR5K_DCU_LCL_IFS_CW_MAX) |
345		AR5K_REG_SM(tq->tqi_aifs, AR5K_DCU_LCL_IFS_AIFS),
346		AR5K_QUEUE_DFS_LOCAL_IFS(queue));
347
348	/*
349	 * Set tx retry limits for this queue
350	 */
351	ath5k_hw_set_tx_retry_limits(ah, queue);
352
353
354	/*
355	 * Set misc registers
356	 */
357
358	/* Enable DCU to wait for next fragment from QCU */
359	AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_DFS_MISC(queue),
360				AR5K_DCU_MISC_FRAG_WAIT);
361
362	/* On Maui and Spirit use the global seqnum on DCU */
363	if (ah->ah_mac_version < AR5K_SREV_AR5211)
364		AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_DFS_MISC(queue),
365					AR5K_DCU_MISC_SEQNUM_CTL);
366
367	/* Constant bit rate period */
368	if (tq->tqi_cbr_period) {
369		ath5k_hw_reg_write(ah, AR5K_REG_SM(tq->tqi_cbr_period,
370					AR5K_QCU_CBRCFG_INTVAL) |
371					AR5K_REG_SM(tq->tqi_cbr_overflow_limit,
372					AR5K_QCU_CBRCFG_ORN_THRES),
373					AR5K_QUEUE_CBRCFG(queue));
374
375		AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_MISC(queue),
376					AR5K_QCU_MISC_FRSHED_CBR);
377
378		if (tq->tqi_cbr_overflow_limit)
379			AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_MISC(queue),
380					AR5K_QCU_MISC_CBR_THRES_ENABLE);
381	}
382
383	/* Ready time interval */
384	if (tq->tqi_ready_time && (tq->tqi_type != AR5K_TX_QUEUE_CAB))
385		ath5k_hw_reg_write(ah, AR5K_REG_SM(tq->tqi_ready_time,
386					AR5K_QCU_RDYTIMECFG_INTVAL) |
387					AR5K_QCU_RDYTIMECFG_ENABLE,
388					AR5K_QUEUE_RDYTIMECFG(queue));
389
390	if (tq->tqi_burst_time) {
391		ath5k_hw_reg_write(ah, AR5K_REG_SM(tq->tqi_burst_time,
392					AR5K_DCU_CHAN_TIME_DUR) |
393					AR5K_DCU_CHAN_TIME_ENABLE,
394					AR5K_QUEUE_DFS_CHANNEL_TIME(queue));
395
396		if (tq->tqi_flags & AR5K_TXQ_FLAG_RDYTIME_EXP_POLICY_ENABLE)
397			AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_MISC(queue),
398					AR5K_QCU_MISC_RDY_VEOL_POLICY);
399	}
400
401	/* Enable/disable Post frame backoff */
402	if (tq->tqi_flags & AR5K_TXQ_FLAG_BACKOFF_DISABLE)
403		ath5k_hw_reg_write(ah, AR5K_DCU_MISC_POST_FR_BKOFF_DIS,
404					AR5K_QUEUE_DFS_MISC(queue));
405
406	/* Enable/disable fragmentation burst backoff */
407	if (tq->tqi_flags & AR5K_TXQ_FLAG_FRAG_BURST_BACKOFF_ENABLE)
408		ath5k_hw_reg_write(ah, AR5K_DCU_MISC_BACKOFF_FRAG,
409					AR5K_QUEUE_DFS_MISC(queue));
410
411	/*
412	 * Set registers by queue type
413	 */
414	switch (tq->tqi_type) {
415	case AR5K_TX_QUEUE_BEACON:
416		AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_MISC(queue),
417				AR5K_QCU_MISC_FRSHED_DBA_GT |
418				AR5K_QCU_MISC_CBREXP_BCN_DIS |
419				AR5K_QCU_MISC_BCN_ENABLE);
420
421		AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_DFS_MISC(queue),
422				(AR5K_DCU_MISC_ARBLOCK_CTL_GLOBAL <<
423				AR5K_DCU_MISC_ARBLOCK_CTL_S) |
424				AR5K_DCU_MISC_ARBLOCK_IGNORE |
425				AR5K_DCU_MISC_POST_FR_BKOFF_DIS |
426				AR5K_DCU_MISC_BCN_ENABLE);
427		break;
428
429	case AR5K_TX_QUEUE_CAB:
430		/* XXX: use BCN_SENT_GT, if we can figure out how */
431		AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_MISC(queue),
432					AR5K_QCU_MISC_FRSHED_DBA_GT |
433					AR5K_QCU_MISC_CBREXP_DIS |
434					AR5K_QCU_MISC_CBREXP_BCN_DIS);
435
436		ath5k_hw_reg_write(ah, ((tq->tqi_ready_time -
437					(AR5K_TUNE_SW_BEACON_RESP -
438					AR5K_TUNE_DMA_BEACON_RESP) -
439				AR5K_TUNE_ADDITIONAL_SWBA_BACKOFF) * 1024) |
440					AR5K_QCU_RDYTIMECFG_ENABLE,
441					AR5K_QUEUE_RDYTIMECFG(queue));
442
443		AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_DFS_MISC(queue),
444					(AR5K_DCU_MISC_ARBLOCK_CTL_GLOBAL <<
445					AR5K_DCU_MISC_ARBLOCK_CTL_S));
446		break;
447
448	case AR5K_TX_QUEUE_UAPSD:
449		AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_MISC(queue),
450					AR5K_QCU_MISC_CBREXP_DIS);
451		break;
452
453	case AR5K_TX_QUEUE_DATA:
454	default:
455			break;
456	}
457
458	/* TODO: Handle frame compression */
459
460	/*
461	 * Enable interrupts for this tx queue
462	 * in the secondary interrupt mask registers
463	 */
464	if (tq->tqi_flags & AR5K_TXQ_FLAG_TXOKINT_ENABLE)
465		AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_txok, queue);
466
467	if (tq->tqi_flags & AR5K_TXQ_FLAG_TXERRINT_ENABLE)
468		AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_txerr, queue);
469
470	if (tq->tqi_flags & AR5K_TXQ_FLAG_TXURNINT_ENABLE)
471		AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_txurn, queue);
472
473	if (tq->tqi_flags & AR5K_TXQ_FLAG_TXDESCINT_ENABLE)
474		AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_txdesc, queue);
475
476	if (tq->tqi_flags & AR5K_TXQ_FLAG_TXEOLINT_ENABLE)
477		AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_txeol, queue);
478
479	if (tq->tqi_flags & AR5K_TXQ_FLAG_CBRORNINT_ENABLE)
480		AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_cbrorn, queue);
481
482	if (tq->tqi_flags & AR5K_TXQ_FLAG_CBRURNINT_ENABLE)
483		AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_cbrurn, queue);
484
485	if (tq->tqi_flags & AR5K_TXQ_FLAG_QTRIGINT_ENABLE)
486		AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_qtrig, queue);
487
488	if (tq->tqi_flags & AR5K_TXQ_FLAG_TXNOFRMINT_ENABLE)
489		AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_nofrm, queue);
490
491	/* Update secondary interrupt mask registers */
492
493	/* Filter out inactive queues */
494	ah->ah_txq_imr_txok &= ah->ah_txq_status;
495	ah->ah_txq_imr_txerr &= ah->ah_txq_status;
496	ah->ah_txq_imr_txurn &= ah->ah_txq_status;
497	ah->ah_txq_imr_txdesc &= ah->ah_txq_status;
498	ah->ah_txq_imr_txeol &= ah->ah_txq_status;
499	ah->ah_txq_imr_cbrorn &= ah->ah_txq_status;
500	ah->ah_txq_imr_cbrurn &= ah->ah_txq_status;
501	ah->ah_txq_imr_qtrig &= ah->ah_txq_status;
502	ah->ah_txq_imr_nofrm &= ah->ah_txq_status;
503
504	ath5k_hw_reg_write(ah, AR5K_REG_SM(ah->ah_txq_imr_txok,
505					AR5K_SIMR0_QCU_TXOK) |
506					AR5K_REG_SM(ah->ah_txq_imr_txdesc,
507					AR5K_SIMR0_QCU_TXDESC),
508					AR5K_SIMR0);
509
510	ath5k_hw_reg_write(ah, AR5K_REG_SM(ah->ah_txq_imr_txerr,
511					AR5K_SIMR1_QCU_TXERR) |
512					AR5K_REG_SM(ah->ah_txq_imr_txeol,
513					AR5K_SIMR1_QCU_TXEOL),
514					AR5K_SIMR1);
515
516	/* Update SIMR2 but don't overwrite rest simr2 settings */
517	AR5K_REG_DISABLE_BITS(ah, AR5K_SIMR2, AR5K_SIMR2_QCU_TXURN);
518	AR5K_REG_ENABLE_BITS(ah, AR5K_SIMR2,
519				AR5K_REG_SM(ah->ah_txq_imr_txurn,
520				AR5K_SIMR2_QCU_TXURN));
521
522	ath5k_hw_reg_write(ah, AR5K_REG_SM(ah->ah_txq_imr_cbrorn,
523				AR5K_SIMR3_QCBRORN) |
524				AR5K_REG_SM(ah->ah_txq_imr_cbrurn,
525				AR5K_SIMR3_QCBRURN),
526				AR5K_SIMR3);
527
528	ath5k_hw_reg_write(ah, AR5K_REG_SM(ah->ah_txq_imr_qtrig,
529				AR5K_SIMR4_QTRIG), AR5K_SIMR4);
530
531	/* Set TXNOFRM_QCU for the queues with TXNOFRM enabled */
532	ath5k_hw_reg_write(ah, AR5K_REG_SM(ah->ah_txq_imr_nofrm,
533				AR5K_TXNOFRM_QCU), AR5K_TXNOFRM);
534
535	/* No queue has TXNOFRM enabled, disable the interrupt
536	 * by setting AR5K_TXNOFRM to zero */
537	if (ah->ah_txq_imr_nofrm == 0)
538		ath5k_hw_reg_write(ah, 0, AR5K_TXNOFRM);
539
540	/* Set QCU mask for this DCU to save power */
541	AR5K_REG_WRITE_Q(ah, AR5K_QUEUE_QCUMASK(queue), queue);
542
543	return 0;
544}
545
546
547/**************************\
548* Global QCU/DCU functions *
549\**************************/
550
551/**
552 * ath5k_hw_set_ifs_intervals()  - Set global inter-frame spaces on DCU
553 * @ah: The &struct ath5k_hw
554 * @slot_time: Slot time in us
555 *
556 * Sets the global IFS intervals on DCU (also works on AR5210) for
557 * the given slot time and the current bwmode.
558 */
559int ath5k_hw_set_ifs_intervals(struct ath5k_hw *ah, unsigned int slot_time)
560{
561	struct ieee80211_channel *channel = ah->ah_current_channel;
562	enum ieee80211_band band;
563	struct ieee80211_supported_band *sband;
564	struct ieee80211_rate *rate;
565	u32 ack_tx_time, eifs, eifs_clock, sifs, sifs_clock;
566	u32 slot_time_clock = ath5k_hw_htoclock(ah, slot_time);
567	u32 rate_flags, i;
568
569	if (slot_time < 6 || slot_time_clock > AR5K_SLOT_TIME_MAX)
570		return -EINVAL;
571
572	sifs = ath5k_hw_get_default_sifs(ah);
573	sifs_clock = ath5k_hw_htoclock(ah, sifs - 2);
574
575	/* EIFS
576	 * Txtime of ack at lowest rate + SIFS + DIFS
577	 * (DIFS = SIFS + 2 * Slot time)
578	 *
579	 * Note: HAL has some predefined values for EIFS
580	 * Turbo:   (37 + 2 * 6)
581	 * Default: (74 + 2 * 9)
582	 * Half:    (149 + 2 * 13)
583	 * Quarter: (298 + 2 * 21)
584	 *
585	 * (74 + 2 * 6) for AR5210 default and turbo !
586	 *
587	 * According to the formula we have
588	 * ack_tx_time = 25 for turbo and
589	 * ack_tx_time = 42.5 * clock multiplier
590	 * for default/half/quarter.
591	 *
592	 * This can't be right, 42 is what we would get
593	 * from ath5k_hw_get_frame_dur_for_bwmode or
594	 * ieee80211_generic_frame_duration for zero frame
595	 * length and without SIFS !
596	 *
597	 * Also we have different lowest rate for 802.11a
598	 */
599	if (channel->band == IEEE80211_BAND_5GHZ)
600		band = IEEE80211_BAND_5GHZ;
601	else
602		band = IEEE80211_BAND_2GHZ;
603
604	switch (ah->ah_bwmode) {
605	case AR5K_BWMODE_5MHZ:
606		rate_flags = IEEE80211_RATE_SUPPORTS_5MHZ;
607		break;
608	case AR5K_BWMODE_10MHZ:
609		rate_flags = IEEE80211_RATE_SUPPORTS_10MHZ;
610		break;
611	default:
612		rate_flags = 0;
613		break;
614	}
615	sband = &ah->sbands[band];
616	rate = NULL;
617	for (i = 0; i < sband->n_bitrates; i++) {
618		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
619			continue;
620		rate = &sband->bitrates[i];
621		break;
622	}
623	if (WARN_ON(!rate))
624		return -EINVAL;
625
626	ack_tx_time = ath5k_hw_get_frame_duration(ah, band, 10, rate, false);
627
628	/* ack_tx_time includes an SIFS already */
629	eifs = ack_tx_time + sifs + 2 * slot_time;
630	eifs_clock = ath5k_hw_htoclock(ah, eifs);
631
632	/* Set IFS settings on AR5210 */
633	if (ah->ah_version == AR5K_AR5210) {
634		u32 pifs, pifs_clock, difs, difs_clock;
635
636		/* Set slot time */
637		ath5k_hw_reg_write(ah, slot_time_clock, AR5K_SLOT_TIME);
638
639		/* Set EIFS */
640		eifs_clock = AR5K_REG_SM(eifs_clock, AR5K_IFS1_EIFS);
641
642		/* PIFS = Slot time + SIFS */
643		pifs = slot_time + sifs;
644		pifs_clock = ath5k_hw_htoclock(ah, pifs);
645		pifs_clock = AR5K_REG_SM(pifs_clock, AR5K_IFS1_PIFS);
646
647		/* DIFS = SIFS + 2 * Slot time */
648		difs = sifs + 2 * slot_time;
649		difs_clock = ath5k_hw_htoclock(ah, difs);
650
651		/* Set SIFS/DIFS */
652		ath5k_hw_reg_write(ah, (difs_clock <<
653				AR5K_IFS0_DIFS_S) | sifs_clock,
654				AR5K_IFS0);
655
656		/* Set PIFS/EIFS and preserve AR5K_INIT_CARR_SENSE_EN */
657		ath5k_hw_reg_write(ah, pifs_clock | eifs_clock |
658				(AR5K_INIT_CARR_SENSE_EN << AR5K_IFS1_CS_EN_S),
659				AR5K_IFS1);
660
661		return 0;
662	}
663
664	/* Set IFS slot time */
665	ath5k_hw_reg_write(ah, slot_time_clock, AR5K_DCU_GBL_IFS_SLOT);
666
667	/* Set EIFS interval */
668	ath5k_hw_reg_write(ah, eifs_clock, AR5K_DCU_GBL_IFS_EIFS);
669
670	/* Set SIFS interval in usecs */
671	AR5K_REG_WRITE_BITS(ah, AR5K_DCU_GBL_IFS_MISC,
672				AR5K_DCU_GBL_IFS_MISC_SIFS_DUR_USEC,
673				sifs);
674
675	/* Set SIFS interval in clock cycles */
676	ath5k_hw_reg_write(ah, sifs_clock, AR5K_DCU_GBL_IFS_SIFS);
677
678	return 0;
679}
680
681
682/**
683 * ath5k_hw_init_queues() - Initialize tx queues
684 * @ah: The &struct ath5k_hw
685 *
686 * Initializes all tx queues based on information on
687 * ah->ah_txq* set by the driver
688 */
689int
690ath5k_hw_init_queues(struct ath5k_hw *ah)
691{
692	int i, ret;
693
694	/* TODO: HW Compression support for data queues */
695	/* TODO: Burst prefetch for data queues */
696
697	/*
698	 * Reset queues and start beacon timers at the end of the reset routine
699	 * This also sets QCU mask on each DCU for 1:1 qcu to dcu mapping
700	 * Note: If we want we can assign multiple qcus on one dcu.
701	 */
702	if (ah->ah_version != AR5K_AR5210)
703		for (i = 0; i < ah->ah_capabilities.cap_queues.q_tx_num; i++) {
704			ret = ath5k_hw_reset_tx_queue(ah, i);
705			if (ret) {
706				ATH5K_ERR(ah,
707					"failed to reset TX queue #%d\n", i);
708				return ret;
709			}
710		}
711	else
712		/* No QCU/DCU on AR5210, just set tx
713		 * retry limits. We set IFS parameters
714		 * on ath5k_hw_set_ifs_intervals */
715		ath5k_hw_set_tx_retry_limits(ah, 0);
716
717	/* Set the turbo flag when operating on 40MHz */
718	if (ah->ah_bwmode == AR5K_BWMODE_40MHZ)
719		AR5K_REG_ENABLE_BITS(ah, AR5K_DCU_GBL_IFS_MISC,
720				AR5K_DCU_GBL_IFS_MISC_TURBO_MODE);
721
722	/* If we didn't set IFS timings through
723	 * ath5k_hw_set_coverage_class make sure
724	 * we set them here */
725	if (!ah->ah_coverage_class) {
726		unsigned int slot_time = ath5k_hw_get_default_slottime(ah);
727		ath5k_hw_set_ifs_intervals(ah, slot_time);
728	}
729
730	return 0;
731}
732