xref: /linux/drivers/net/wireless/intel/iwlegacy/4965-rs.c (revision 6fdcba32711044c35c0e1b094cbd8f3f0b4472c9)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /******************************************************************************
3  *
4  * Copyright(c) 2005 - 2011 Intel Corporation. All rights reserved.
5  *
6  * Contact Information:
7  *  Intel Linux Wireless <ilw@linux.intel.com>
8  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
9  *
10  *****************************************************************************/
11 #include <linux/kernel.h>
12 #include <linux/skbuff.h>
13 #include <linux/slab.h>
14 #include <net/mac80211.h>
15 
16 #include <linux/netdevice.h>
17 #include <linux/etherdevice.h>
18 #include <linux/delay.h>
19 
20 #include <linux/workqueue.h>
21 
22 #include "common.h"
23 #include "4965.h"
24 
25 #define IL4965_RS_NAME "iwl-4965-rs"
26 
27 #define NUM_TRY_BEFORE_ANT_TOGGLE 1
28 #define IL_NUMBER_TRY      1
29 #define IL_HT_NUMBER_TRY   3
30 
31 #define RATE_MAX_WINDOW		62	/* # tx in history win */
32 #define RATE_MIN_FAILURE_TH		6	/* min failures to calc tpt */
33 #define RATE_MIN_SUCCESS_TH		8	/* min successes to calc tpt */
34 
35 /* max allowed rate miss before sync LQ cmd */
36 #define IL_MISSED_RATE_MAX		15
37 /* max time to accum history 2 seconds */
38 #define RATE_SCALE_FLUSH_INTVL   (3*HZ)
39 
40 static u8 rs_ht_to_legacy[] = {
41 	RATE_6M_IDX, RATE_6M_IDX,
42 	RATE_6M_IDX, RATE_6M_IDX,
43 	RATE_6M_IDX,
44 	RATE_6M_IDX, RATE_9M_IDX,
45 	RATE_12M_IDX, RATE_18M_IDX,
46 	RATE_24M_IDX, RATE_36M_IDX,
47 	RATE_48M_IDX, RATE_54M_IDX
48 };
49 
50 static const u8 ant_toggle_lookup[] = {
51 	/*ANT_NONE -> */ ANT_NONE,
52 	/*ANT_A    -> */ ANT_B,
53 	/*ANT_B    -> */ ANT_C,
54 	/*ANT_AB   -> */ ANT_BC,
55 	/*ANT_C    -> */ ANT_A,
56 	/*ANT_AC   -> */ ANT_AB,
57 	/*ANT_BC   -> */ ANT_AC,
58 	/*ANT_ABC  -> */ ANT_ABC,
59 };
60 
61 #define IL_DECLARE_RATE_INFO(r, s, ip, in, rp, rn, pp, np)    \
62 	[RATE_##r##M_IDX] = { RATE_##r##M_PLCP,      \
63 				    RATE_SISO_##s##M_PLCP, \
64 				    RATE_MIMO2_##s##M_PLCP,\
65 				    RATE_##r##M_IEEE,      \
66 				    RATE_##ip##M_IDX,    \
67 				    RATE_##in##M_IDX,    \
68 				    RATE_##rp##M_IDX,    \
69 				    RATE_##rn##M_IDX,    \
70 				    RATE_##pp##M_IDX,    \
71 				    RATE_##np##M_IDX }
72 
73 /*
74  * Parameter order:
75  *   rate, ht rate, prev rate, next rate, prev tgg rate, next tgg rate
76  *
77  * If there isn't a valid next or previous rate then INV is used which
78  * maps to RATE_INVALID
79  *
80  */
81 const struct il_rate_info il_rates[RATE_COUNT] = {
82 	IL_DECLARE_RATE_INFO(1, INV, INV, 2, INV, 2, INV, 2),	/*  1mbps */
83 	IL_DECLARE_RATE_INFO(2, INV, 1, 5, 1, 5, 1, 5),		/*  2mbps */
84 	IL_DECLARE_RATE_INFO(5, INV, 2, 6, 2, 11, 2, 11),	/*5.5mbps */
85 	IL_DECLARE_RATE_INFO(11, INV, 9, 12, 9, 12, 5, 18),	/* 11mbps */
86 	IL_DECLARE_RATE_INFO(6, 6, 5, 9, 5, 11, 5, 11),		/*  6mbps */
87 	IL_DECLARE_RATE_INFO(9, 6, 6, 11, 6, 11, 5, 11),	/*  9mbps */
88 	IL_DECLARE_RATE_INFO(12, 12, 11, 18, 11, 18, 11, 18),	/* 12mbps */
89 	IL_DECLARE_RATE_INFO(18, 18, 12, 24, 12, 24, 11, 24),	/* 18mbps */
90 	IL_DECLARE_RATE_INFO(24, 24, 18, 36, 18, 36, 18, 36),	/* 24mbps */
91 	IL_DECLARE_RATE_INFO(36, 36, 24, 48, 24, 48, 24, 48),	/* 36mbps */
92 	IL_DECLARE_RATE_INFO(48, 48, 36, 54, 36, 54, 36, 54),	/* 48mbps */
93 	IL_DECLARE_RATE_INFO(54, 54, 48, INV, 48, INV, 48, INV),/* 54mbps */
94 	IL_DECLARE_RATE_INFO(60, 60, 48, INV, 48, INV, 48, INV),/* 60mbps */
95 };
96 
97 static int
98 il4965_hwrate_to_plcp_idx(u32 rate_n_flags)
99 {
100 	int idx = 0;
101 
102 	/* HT rate format */
103 	if (rate_n_flags & RATE_MCS_HT_MSK) {
104 		idx = (rate_n_flags & 0xff);
105 
106 		if (idx >= RATE_MIMO2_6M_PLCP)
107 			idx = idx - RATE_MIMO2_6M_PLCP;
108 
109 		idx += IL_FIRST_OFDM_RATE;
110 		/* skip 9M not supported in ht */
111 		if (idx >= RATE_9M_IDX)
112 			idx += 1;
113 		if (idx >= IL_FIRST_OFDM_RATE && idx <= IL_LAST_OFDM_RATE)
114 			return idx;
115 
116 		/* legacy rate format, search for match in table */
117 	} else {
118 		for (idx = 0; idx < ARRAY_SIZE(il_rates); idx++)
119 			if (il_rates[idx].plcp == (rate_n_flags & 0xFF))
120 				return idx;
121 	}
122 
123 	return -1;
124 }
125 
126 static void il4965_rs_rate_scale_perform(struct il_priv *il,
127 					 struct sk_buff *skb,
128 					 struct ieee80211_sta *sta,
129 					 struct il_lq_sta *lq_sta);
130 static void il4965_rs_fill_link_cmd(struct il_priv *il,
131 				    struct il_lq_sta *lq_sta, u32 rate_n_flags);
132 static void il4965_rs_stay_in_table(struct il_lq_sta *lq_sta,
133 				    bool force_search);
134 
135 #ifdef CONFIG_MAC80211_DEBUGFS
136 static void il4965_rs_dbgfs_set_mcs(struct il_lq_sta *lq_sta,
137 				    u32 *rate_n_flags, int idx);
138 #else
139 static void
140 il4965_rs_dbgfs_set_mcs(struct il_lq_sta *lq_sta, u32 * rate_n_flags, int idx)
141 {
142 }
143 #endif
144 
145 /**
146  * The following tables contain the expected throughput metrics for all rates
147  *
148  *	1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
149  *
150  * where invalid entries are zeros.
151  *
152  * CCK rates are only valid in legacy table and will only be used in G
153  * (2.4 GHz) band.
154  */
155 
156 static s32 expected_tpt_legacy[RATE_COUNT] = {
157 	7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 0
158 };
159 
160 static s32 expected_tpt_siso20MHz[4][RATE_COUNT] = {
161 	{0, 0, 0, 0, 42, 0, 76, 102, 124, 158, 183, 193, 202},	/* Norm */
162 	{0, 0, 0, 0, 46, 0, 82, 110, 132, 167, 192, 202, 210},	/* SGI */
163 	{0, 0, 0, 0, 48, 0, 93, 135, 176, 251, 319, 351, 381},	/* AGG */
164 	{0, 0, 0, 0, 53, 0, 102, 149, 193, 275, 348, 381, 413},	/* AGG+SGI */
165 };
166 
167 static s32 expected_tpt_siso40MHz[4][RATE_COUNT] = {
168 	{0, 0, 0, 0, 77, 0, 127, 160, 184, 220, 242, 250, 257},	/* Norm */
169 	{0, 0, 0, 0, 83, 0, 135, 169, 193, 229, 250, 257, 264},	/* SGI */
170 	{0, 0, 0, 0, 96, 0, 182, 259, 328, 451, 553, 598, 640},	/* AGG */
171 	{0, 0, 0, 0, 106, 0, 199, 282, 357, 487, 593, 640, 683},	/* AGG+SGI */
172 };
173 
174 static s32 expected_tpt_mimo2_20MHz[4][RATE_COUNT] = {
175 	{0, 0, 0, 0, 74, 0, 123, 155, 179, 213, 235, 243, 250},	/* Norm */
176 	{0, 0, 0, 0, 81, 0, 131, 164, 187, 221, 242, 250, 256},	/* SGI */
177 	{0, 0, 0, 0, 92, 0, 175, 250, 317, 436, 534, 578, 619},	/* AGG */
178 	{0, 0, 0, 0, 102, 0, 192, 273, 344, 470, 573, 619, 660},	/* AGG+SGI */
179 };
180 
181 static s32 expected_tpt_mimo2_40MHz[4][RATE_COUNT] = {
182 	{0, 0, 0, 0, 123, 0, 182, 214, 235, 264, 279, 285, 289},	/* Norm */
183 	{0, 0, 0, 0, 131, 0, 191, 222, 242, 270, 284, 289, 293},	/* SGI */
184 	{0, 0, 0, 0, 180, 0, 327, 446, 545, 708, 828, 878, 922},	/* AGG */
185 	{0, 0, 0, 0, 197, 0, 355, 481, 584, 752, 872, 922, 966},	/* AGG+SGI */
186 };
187 
188 /* mbps, mcs */
189 static const struct il_rate_mcs_info il_rate_mcs[RATE_COUNT] = {
190 	{"1", "BPSK DSSS"},
191 	{"2", "QPSK DSSS"},
192 	{"5.5", "BPSK CCK"},
193 	{"11", "QPSK CCK"},
194 	{"6", "BPSK 1/2"},
195 	{"9", "BPSK 1/2"},
196 	{"12", "QPSK 1/2"},
197 	{"18", "QPSK 3/4"},
198 	{"24", "16QAM 1/2"},
199 	{"36", "16QAM 3/4"},
200 	{"48", "64QAM 2/3"},
201 	{"54", "64QAM 3/4"},
202 	{"60", "64QAM 5/6"},
203 };
204 
205 #define MCS_IDX_PER_STREAM	(8)
206 
207 static inline u8
208 il4965_rs_extract_rate(u32 rate_n_flags)
209 {
210 	return (u8) (rate_n_flags & 0xFF);
211 }
212 
213 static void
214 il4965_rs_rate_scale_clear_win(struct il_rate_scale_data *win)
215 {
216 	win->data = 0;
217 	win->success_counter = 0;
218 	win->success_ratio = IL_INVALID_VALUE;
219 	win->counter = 0;
220 	win->average_tpt = IL_INVALID_VALUE;
221 	win->stamp = 0;
222 }
223 
224 static inline u8
225 il4965_rs_is_valid_ant(u8 valid_antenna, u8 ant_type)
226 {
227 	return (ant_type & valid_antenna) == ant_type;
228 }
229 
230 /*
231  *	removes the old data from the stats. All data that is older than
232  *	TID_MAX_TIME_DIFF, will be deleted.
233  */
234 static void
235 il4965_rs_tl_rm_old_stats(struct il_traffic_load *tl, u32 curr_time)
236 {
237 	/* The oldest age we want to keep */
238 	u32 oldest_time = curr_time - TID_MAX_TIME_DIFF;
239 
240 	while (tl->queue_count && tl->time_stamp < oldest_time) {
241 		tl->total -= tl->packet_count[tl->head];
242 		tl->packet_count[tl->head] = 0;
243 		tl->time_stamp += TID_QUEUE_CELL_SPACING;
244 		tl->queue_count--;
245 		tl->head++;
246 		if (tl->head >= TID_QUEUE_MAX_SIZE)
247 			tl->head = 0;
248 	}
249 }
250 
251 /*
252  *	increment traffic load value for tid and also remove
253  *	any old values if passed the certain time period
254  */
255 static u8
256 il4965_rs_tl_add_packet(struct il_lq_sta *lq_data, struct ieee80211_hdr *hdr)
257 {
258 	u32 curr_time = jiffies_to_msecs(jiffies);
259 	u32 time_diff;
260 	s32 idx;
261 	struct il_traffic_load *tl = NULL;
262 	u8 tid;
263 
264 	if (ieee80211_is_data_qos(hdr->frame_control)) {
265 		u8 *qc = ieee80211_get_qos_ctl(hdr);
266 		tid = qc[0] & 0xf;
267 	} else
268 		return MAX_TID_COUNT;
269 
270 	if (unlikely(tid >= TID_MAX_LOAD_COUNT))
271 		return MAX_TID_COUNT;
272 
273 	tl = &lq_data->load[tid];
274 
275 	curr_time -= curr_time % TID_ROUND_VALUE;
276 
277 	/* Happens only for the first packet. Initialize the data */
278 	if (!(tl->queue_count)) {
279 		tl->total = 1;
280 		tl->time_stamp = curr_time;
281 		tl->queue_count = 1;
282 		tl->head = 0;
283 		tl->packet_count[0] = 1;
284 		return MAX_TID_COUNT;
285 	}
286 
287 	time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
288 	idx = time_diff / TID_QUEUE_CELL_SPACING;
289 
290 	/* The history is too long: remove data that is older than */
291 	/* TID_MAX_TIME_DIFF */
292 	if (idx >= TID_QUEUE_MAX_SIZE)
293 		il4965_rs_tl_rm_old_stats(tl, curr_time);
294 
295 	idx = (tl->head + idx) % TID_QUEUE_MAX_SIZE;
296 	tl->packet_count[idx] = tl->packet_count[idx] + 1;
297 	tl->total = tl->total + 1;
298 
299 	if ((idx + 1) > tl->queue_count)
300 		tl->queue_count = idx + 1;
301 
302 	return tid;
303 }
304 
305 /*
306 	get the traffic load value for tid
307 */
308 static u32
309 il4965_rs_tl_get_load(struct il_lq_sta *lq_data, u8 tid)
310 {
311 	u32 curr_time = jiffies_to_msecs(jiffies);
312 	u32 time_diff;
313 	s32 idx;
314 	struct il_traffic_load *tl = NULL;
315 
316 	if (tid >= TID_MAX_LOAD_COUNT)
317 		return 0;
318 
319 	tl = &(lq_data->load[tid]);
320 
321 	curr_time -= curr_time % TID_ROUND_VALUE;
322 
323 	if (!(tl->queue_count))
324 		return 0;
325 
326 	time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
327 	idx = time_diff / TID_QUEUE_CELL_SPACING;
328 
329 	/* The history is too long: remove data that is older than */
330 	/* TID_MAX_TIME_DIFF */
331 	if (idx >= TID_QUEUE_MAX_SIZE)
332 		il4965_rs_tl_rm_old_stats(tl, curr_time);
333 
334 	return tl->total;
335 }
336 
337 static int
338 il4965_rs_tl_turn_on_agg_for_tid(struct il_priv *il, struct il_lq_sta *lq_data,
339 				 u8 tid, struct ieee80211_sta *sta)
340 {
341 	int ret = -EAGAIN;
342 	u32 load;
343 
344 	load = il4965_rs_tl_get_load(lq_data, tid);
345 
346 	if (load > IL_AGG_LOAD_THRESHOLD) {
347 		D_HT("Starting Tx agg: STA: %pM tid: %d\n", sta->addr, tid);
348 		ret = ieee80211_start_tx_ba_session(sta, tid, 5000);
349 		if (ret == -EAGAIN) {
350 			/*
351 			 * driver and mac80211 is out of sync
352 			 * this might be cause by reloading firmware
353 			 * stop the tx ba session here
354 			 */
355 			IL_ERR("Fail start Tx agg on tid: %d\n", tid);
356 			ieee80211_stop_tx_ba_session(sta, tid);
357 		}
358 	} else
359 		D_HT("Aggregation not enabled for tid %d because load = %u\n",
360 		     tid, load);
361 
362 	return ret;
363 }
364 
365 static void
366 il4965_rs_tl_turn_on_agg(struct il_priv *il, u8 tid, struct il_lq_sta *lq_data,
367 			 struct ieee80211_sta *sta)
368 {
369 	if (tid < TID_MAX_LOAD_COUNT)
370 		il4965_rs_tl_turn_on_agg_for_tid(il, lq_data, tid, sta);
371 	else
372 		IL_ERR("tid exceeds max load count: %d/%d\n", tid,
373 		       TID_MAX_LOAD_COUNT);
374 }
375 
376 static inline int
377 il4965_get_il4965_num_of_ant_from_rate(u32 rate_n_flags)
378 {
379 	return !!(rate_n_flags & RATE_MCS_ANT_A_MSK) +
380 	    !!(rate_n_flags & RATE_MCS_ANT_B_MSK) +
381 	    !!(rate_n_flags & RATE_MCS_ANT_C_MSK);
382 }
383 
384 /*
385  * Static function to get the expected throughput from an il_scale_tbl_info
386  * that wraps a NULL pointer check
387  */
388 static s32
389 il4965_get_expected_tpt(struct il_scale_tbl_info *tbl, int rs_idx)
390 {
391 	if (tbl->expected_tpt)
392 		return tbl->expected_tpt[rs_idx];
393 	return 0;
394 }
395 
396 /**
397  * il4965_rs_collect_tx_data - Update the success/failure sliding win
398  *
399  * We keep a sliding win of the last 62 packets transmitted
400  * at this rate.  win->data contains the bitmask of successful
401  * packets.
402  */
403 static int
404 il4965_rs_collect_tx_data(struct il_scale_tbl_info *tbl, int scale_idx,
405 			  int attempts, int successes)
406 {
407 	struct il_rate_scale_data *win = NULL;
408 	static const u64 mask = (((u64) 1) << (RATE_MAX_WINDOW - 1));
409 	s32 fail_count, tpt;
410 
411 	if (scale_idx < 0 || scale_idx >= RATE_COUNT)
412 		return -EINVAL;
413 
414 	/* Select win for current tx bit rate */
415 	win = &(tbl->win[scale_idx]);
416 
417 	/* Get expected throughput */
418 	tpt = il4965_get_expected_tpt(tbl, scale_idx);
419 
420 	/*
421 	 * Keep track of only the latest 62 tx frame attempts in this rate's
422 	 * history win; anything older isn't really relevant any more.
423 	 * If we have filled up the sliding win, drop the oldest attempt;
424 	 * if the oldest attempt (highest bit in bitmap) shows "success",
425 	 * subtract "1" from the success counter (this is the main reason
426 	 * we keep these bitmaps!).
427 	 */
428 	while (attempts > 0) {
429 		if (win->counter >= RATE_MAX_WINDOW) {
430 
431 			/* remove earliest */
432 			win->counter = RATE_MAX_WINDOW - 1;
433 
434 			if (win->data & mask) {
435 				win->data &= ~mask;
436 				win->success_counter--;
437 			}
438 		}
439 
440 		/* Increment frames-attempted counter */
441 		win->counter++;
442 
443 		/* Shift bitmap by one frame to throw away oldest history */
444 		win->data <<= 1;
445 
446 		/* Mark the most recent #successes attempts as successful */
447 		if (successes > 0) {
448 			win->success_counter++;
449 			win->data |= 0x1;
450 			successes--;
451 		}
452 
453 		attempts--;
454 	}
455 
456 	/* Calculate current success ratio, avoid divide-by-0! */
457 	if (win->counter > 0)
458 		win->success_ratio =
459 		    128 * (100 * win->success_counter) / win->counter;
460 	else
461 		win->success_ratio = IL_INVALID_VALUE;
462 
463 	fail_count = win->counter - win->success_counter;
464 
465 	/* Calculate average throughput, if we have enough history. */
466 	if (fail_count >= RATE_MIN_FAILURE_TH ||
467 	    win->success_counter >= RATE_MIN_SUCCESS_TH)
468 		win->average_tpt = (win->success_ratio * tpt + 64) / 128;
469 	else
470 		win->average_tpt = IL_INVALID_VALUE;
471 
472 	/* Tag this win as having been updated */
473 	win->stamp = jiffies;
474 
475 	return 0;
476 }
477 
478 /*
479  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
480  */
481 static u32
482 il4965_rate_n_flags_from_tbl(struct il_priv *il, struct il_scale_tbl_info *tbl,
483 			     int idx, u8 use_green)
484 {
485 	u32 rate_n_flags = 0;
486 
487 	if (is_legacy(tbl->lq_type)) {
488 		rate_n_flags = il_rates[idx].plcp;
489 		if (idx >= IL_FIRST_CCK_RATE && idx <= IL_LAST_CCK_RATE)
490 			rate_n_flags |= RATE_MCS_CCK_MSK;
491 
492 	} else if (is_Ht(tbl->lq_type)) {
493 		if (idx > IL_LAST_OFDM_RATE) {
494 			IL_ERR("Invalid HT rate idx %d\n", idx);
495 			idx = IL_LAST_OFDM_RATE;
496 		}
497 		rate_n_flags = RATE_MCS_HT_MSK;
498 
499 		if (is_siso(tbl->lq_type))
500 			rate_n_flags |= il_rates[idx].plcp_siso;
501 		else
502 			rate_n_flags |= il_rates[idx].plcp_mimo2;
503 	} else {
504 		IL_ERR("Invalid tbl->lq_type %d\n", tbl->lq_type);
505 	}
506 
507 	rate_n_flags |=
508 	    ((tbl->ant_type << RATE_MCS_ANT_POS) & RATE_MCS_ANT_ABC_MSK);
509 
510 	if (is_Ht(tbl->lq_type)) {
511 		if (tbl->is_ht40) {
512 			if (tbl->is_dup)
513 				rate_n_flags |= RATE_MCS_DUP_MSK;
514 			else
515 				rate_n_flags |= RATE_MCS_HT40_MSK;
516 		}
517 		if (tbl->is_SGI)
518 			rate_n_flags |= RATE_MCS_SGI_MSK;
519 
520 		if (use_green) {
521 			rate_n_flags |= RATE_MCS_GF_MSK;
522 			if (is_siso(tbl->lq_type) && tbl->is_SGI) {
523 				rate_n_flags &= ~RATE_MCS_SGI_MSK;
524 				IL_ERR("GF was set with SGI:SISO\n");
525 			}
526 		}
527 	}
528 	return rate_n_flags;
529 }
530 
531 /*
532  * Interpret uCode API's rate_n_flags format,
533  * fill "search" or "active" tx mode table.
534  */
535 static int
536 il4965_rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
537 				enum nl80211_band band,
538 				struct il_scale_tbl_info *tbl, int *rate_idx)
539 {
540 	u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
541 	u8 il4965_num_of_ant =
542 	    il4965_get_il4965_num_of_ant_from_rate(rate_n_flags);
543 	u8 mcs;
544 
545 	memset(tbl, 0, sizeof(struct il_scale_tbl_info));
546 	*rate_idx = il4965_hwrate_to_plcp_idx(rate_n_flags);
547 
548 	if (*rate_idx == RATE_INVALID) {
549 		*rate_idx = -1;
550 		return -EINVAL;
551 	}
552 	tbl->is_SGI = 0;	/* default legacy setup */
553 	tbl->is_ht40 = 0;
554 	tbl->is_dup = 0;
555 	tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
556 	tbl->lq_type = LQ_NONE;
557 	tbl->max_search = IL_MAX_SEARCH;
558 
559 	/* legacy rate format */
560 	if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
561 		if (il4965_num_of_ant == 1) {
562 			if (band == NL80211_BAND_5GHZ)
563 				tbl->lq_type = LQ_A;
564 			else
565 				tbl->lq_type = LQ_G;
566 		}
567 		/* HT rate format */
568 	} else {
569 		if (rate_n_flags & RATE_MCS_SGI_MSK)
570 			tbl->is_SGI = 1;
571 
572 		if ((rate_n_flags & RATE_MCS_HT40_MSK) ||
573 		    (rate_n_flags & RATE_MCS_DUP_MSK))
574 			tbl->is_ht40 = 1;
575 
576 		if (rate_n_flags & RATE_MCS_DUP_MSK)
577 			tbl->is_dup = 1;
578 
579 		mcs = il4965_rs_extract_rate(rate_n_flags);
580 
581 		/* SISO */
582 		if (mcs <= RATE_SISO_60M_PLCP) {
583 			if (il4965_num_of_ant == 1)
584 				tbl->lq_type = LQ_SISO;	/*else NONE */
585 			/* MIMO2 */
586 		} else {
587 			if (il4965_num_of_ant == 2)
588 				tbl->lq_type = LQ_MIMO2;
589 		}
590 	}
591 	return 0;
592 }
593 
594 /* switch to another antenna/antennas and return 1 */
595 /* if no other valid antenna found, return 0 */
596 static int
597 il4965_rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
598 			 struct il_scale_tbl_info *tbl)
599 {
600 	u8 new_ant_type;
601 
602 	if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
603 		return 0;
604 
605 	if (!il4965_rs_is_valid_ant(valid_ant, tbl->ant_type))
606 		return 0;
607 
608 	new_ant_type = ant_toggle_lookup[tbl->ant_type];
609 
610 	while (new_ant_type != tbl->ant_type &&
611 	       !il4965_rs_is_valid_ant(valid_ant, new_ant_type))
612 		new_ant_type = ant_toggle_lookup[new_ant_type];
613 
614 	if (new_ant_type == tbl->ant_type)
615 		return 0;
616 
617 	tbl->ant_type = new_ant_type;
618 	*rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
619 	*rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
620 	return 1;
621 }
622 
623 /**
624  * Green-field mode is valid if the station supports it and
625  * there are no non-GF stations present in the BSS.
626  */
627 static bool
628 il4965_rs_use_green(struct il_priv *il, struct ieee80211_sta *sta)
629 {
630 	return (sta->ht_cap.cap & IEEE80211_HT_CAP_GRN_FLD) &&
631 	       !il->ht.non_gf_sta_present;
632 }
633 
634 /**
635  * il4965_rs_get_supported_rates - get the available rates
636  *
637  * if management frame or broadcast frame only return
638  * basic available rates.
639  *
640  */
641 static u16
642 il4965_rs_get_supported_rates(struct il_lq_sta *lq_sta,
643 			      struct ieee80211_hdr *hdr,
644 			      enum il_table_type rate_type)
645 {
646 	if (is_legacy(rate_type)) {
647 		return lq_sta->active_legacy_rate;
648 	} else {
649 		if (is_siso(rate_type))
650 			return lq_sta->active_siso_rate;
651 		else
652 			return lq_sta->active_mimo2_rate;
653 	}
654 }
655 
656 static u16
657 il4965_rs_get_adjacent_rate(struct il_priv *il, u8 idx, u16 rate_mask,
658 			    int rate_type)
659 {
660 	u8 high = RATE_INVALID;
661 	u8 low = RATE_INVALID;
662 
663 	/* 802.11A or ht walks to the next literal adjacent rate in
664 	 * the rate table */
665 	if (is_a_band(rate_type) || !is_legacy(rate_type)) {
666 		int i;
667 		u32 mask;
668 
669 		/* Find the previous rate that is in the rate mask */
670 		i = idx - 1;
671 		for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
672 			if (rate_mask & mask) {
673 				low = i;
674 				break;
675 			}
676 		}
677 
678 		/* Find the next rate that is in the rate mask */
679 		i = idx + 1;
680 		for (mask = (1 << i); i < RATE_COUNT; i++, mask <<= 1) {
681 			if (rate_mask & mask) {
682 				high = i;
683 				break;
684 			}
685 		}
686 
687 		return (high << 8) | low;
688 	}
689 
690 	low = idx;
691 	while (low != RATE_INVALID) {
692 		low = il_rates[low].prev_rs;
693 		if (low == RATE_INVALID)
694 			break;
695 		if (rate_mask & (1 << low))
696 			break;
697 		D_RATE("Skipping masked lower rate: %d\n", low);
698 	}
699 
700 	high = idx;
701 	while (high != RATE_INVALID) {
702 		high = il_rates[high].next_rs;
703 		if (high == RATE_INVALID)
704 			break;
705 		if (rate_mask & (1 << high))
706 			break;
707 		D_RATE("Skipping masked higher rate: %d\n", high);
708 	}
709 
710 	return (high << 8) | low;
711 }
712 
713 static u32
714 il4965_rs_get_lower_rate(struct il_lq_sta *lq_sta,
715 			 struct il_scale_tbl_info *tbl, u8 scale_idx,
716 			 u8 ht_possible)
717 {
718 	s32 low;
719 	u16 rate_mask;
720 	u16 high_low;
721 	u8 switch_to_legacy = 0;
722 	u8 is_green = lq_sta->is_green;
723 	struct il_priv *il = lq_sta->drv;
724 
725 	/* check if we need to switch from HT to legacy rates.
726 	 * assumption is that mandatory rates (1Mbps or 6Mbps)
727 	 * are always supported (spec demand) */
728 	if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_idx)) {
729 		switch_to_legacy = 1;
730 		scale_idx = rs_ht_to_legacy[scale_idx];
731 		if (lq_sta->band == NL80211_BAND_5GHZ)
732 			tbl->lq_type = LQ_A;
733 		else
734 			tbl->lq_type = LQ_G;
735 
736 		if (il4965_num_of_ant(tbl->ant_type) > 1)
737 			tbl->ant_type =
738 			    il4965_first_antenna(il->hw_params.valid_tx_ant);
739 
740 		tbl->is_ht40 = 0;
741 		tbl->is_SGI = 0;
742 		tbl->max_search = IL_MAX_SEARCH;
743 	}
744 
745 	rate_mask = il4965_rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
746 
747 	/* Mask with station rate restriction */
748 	if (is_legacy(tbl->lq_type)) {
749 		/* supp_rates has no CCK bits in A mode */
750 		if (lq_sta->band == NL80211_BAND_5GHZ)
751 			rate_mask =
752 			    (u16) (rate_mask &
753 				   (lq_sta->supp_rates << IL_FIRST_OFDM_RATE));
754 		else
755 			rate_mask = (u16) (rate_mask & lq_sta->supp_rates);
756 	}
757 
758 	/* If we switched from HT to legacy, check current rate */
759 	if (switch_to_legacy && (rate_mask & (1 << scale_idx))) {
760 		low = scale_idx;
761 		goto out;
762 	}
763 
764 	high_low =
765 	    il4965_rs_get_adjacent_rate(lq_sta->drv, scale_idx, rate_mask,
766 					tbl->lq_type);
767 	low = high_low & 0xff;
768 
769 	if (low == RATE_INVALID)
770 		low = scale_idx;
771 
772 out:
773 	return il4965_rate_n_flags_from_tbl(lq_sta->drv, tbl, low, is_green);
774 }
775 
776 /*
777  * Simple function to compare two rate scale table types
778  */
779 static bool
780 il4965_table_type_matches(struct il_scale_tbl_info *a,
781 			  struct il_scale_tbl_info *b)
782 {
783 	return (a->lq_type == b->lq_type && a->ant_type == b->ant_type &&
784 		a->is_SGI == b->is_SGI);
785 }
786 
787 /*
788  * mac80211 sends us Tx status
789  */
790 static void
791 il4965_rs_tx_status(void *il_r, struct ieee80211_supported_band *sband,
792 		    struct ieee80211_sta *sta, void *il_sta,
793 		    struct sk_buff *skb)
794 {
795 	int legacy_success;
796 	int retries;
797 	int rs_idx, mac_idx, i;
798 	struct il_lq_sta *lq_sta = il_sta;
799 	struct il_link_quality_cmd *table;
800 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
801 	struct il_priv *il = (struct il_priv *)il_r;
802 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
803 	enum mac80211_rate_control_flags mac_flags;
804 	u32 tx_rate;
805 	struct il_scale_tbl_info tbl_type;
806 	struct il_scale_tbl_info *curr_tbl, *other_tbl, *tmp_tbl;
807 
808 	D_RATE("get frame ack response, update rate scale win\n");
809 
810 	/* Treat uninitialized rate scaling data same as non-existing. */
811 	if (!lq_sta) {
812 		D_RATE("Station rate scaling not created yet.\n");
813 		return;
814 	} else if (!lq_sta->drv) {
815 		D_RATE("Rate scaling not initialized yet.\n");
816 		return;
817 	}
818 
819 	if (!ieee80211_is_data(hdr->frame_control) ||
820 	    (info->flags & IEEE80211_TX_CTL_NO_ACK))
821 		return;
822 
823 	/* This packet was aggregated but doesn't carry status info */
824 	if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
825 	    !(info->flags & IEEE80211_TX_STAT_AMPDU))
826 		return;
827 
828 	/*
829 	 * Ignore this Tx frame response if its initial rate doesn't match
830 	 * that of latest Link Quality command.  There may be stragglers
831 	 * from a previous Link Quality command, but we're no longer interested
832 	 * in those; they're either from the "active" mode while we're trying
833 	 * to check "search" mode, or a prior "search" mode after we've moved
834 	 * to a new "search" mode (which might become the new "active" mode).
835 	 */
836 	table = &lq_sta->lq;
837 	tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
838 	il4965_rs_get_tbl_info_from_mcs(tx_rate, il->band, &tbl_type, &rs_idx);
839 	if (il->band == NL80211_BAND_5GHZ)
840 		rs_idx -= IL_FIRST_OFDM_RATE;
841 	mac_flags = info->status.rates[0].flags;
842 	mac_idx = info->status.rates[0].idx;
843 	/* For HT packets, map MCS to PLCP */
844 	if (mac_flags & IEEE80211_TX_RC_MCS) {
845 		mac_idx &= RATE_MCS_CODE_MSK;	/* Remove # of streams */
846 		if (mac_idx >= (RATE_9M_IDX - IL_FIRST_OFDM_RATE))
847 			mac_idx++;
848 		/*
849 		 * mac80211 HT idx is always zero-idxed; we need to move
850 		 * HT OFDM rates after CCK rates in 2.4 GHz band
851 		 */
852 		if (il->band == NL80211_BAND_2GHZ)
853 			mac_idx += IL_FIRST_OFDM_RATE;
854 	}
855 	/* Here we actually compare this rate to the latest LQ command */
856 	if (mac_idx < 0 ||
857 	    tbl_type.is_SGI != !!(mac_flags & IEEE80211_TX_RC_SHORT_GI) ||
858 	    tbl_type.is_ht40 != !!(mac_flags & IEEE80211_TX_RC_40_MHZ_WIDTH) ||
859 	    tbl_type.is_dup != !!(mac_flags & IEEE80211_TX_RC_DUP_DATA) ||
860 	    tbl_type.ant_type != info->status.antenna ||
861 	    !!(tx_rate & RATE_MCS_HT_MSK) != !!(mac_flags & IEEE80211_TX_RC_MCS)
862 	    || !!(tx_rate & RATE_MCS_GF_MSK) !=
863 	    !!(mac_flags & IEEE80211_TX_RC_GREEN_FIELD) || rs_idx != mac_idx) {
864 		D_RATE("initial rate %d does not match %d (0x%x)\n", mac_idx,
865 		       rs_idx, tx_rate);
866 		/*
867 		 * Since rates mis-match, the last LQ command may have failed.
868 		 * After IL_MISSED_RATE_MAX mis-matches, resync the uCode with
869 		 * ... driver.
870 		 */
871 		lq_sta->missed_rate_counter++;
872 		if (lq_sta->missed_rate_counter > IL_MISSED_RATE_MAX) {
873 			lq_sta->missed_rate_counter = 0;
874 			il_send_lq_cmd(il, &lq_sta->lq, CMD_ASYNC, false);
875 		}
876 		/* Regardless, ignore this status info for outdated rate */
877 		return;
878 	} else
879 		/* Rate did match, so reset the missed_rate_counter */
880 		lq_sta->missed_rate_counter = 0;
881 
882 	/* Figure out if rate scale algorithm is in active or search table */
883 	if (il4965_table_type_matches
884 	    (&tbl_type, &(lq_sta->lq_info[lq_sta->active_tbl]))) {
885 		curr_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
886 		other_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
887 	} else
888 	    if (il4965_table_type_matches
889 		(&tbl_type, &lq_sta->lq_info[1 - lq_sta->active_tbl])) {
890 		curr_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
891 		other_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
892 	} else {
893 		D_RATE("Neither active nor search matches tx rate\n");
894 		tmp_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
895 		D_RATE("active- lq:%x, ant:%x, SGI:%d\n", tmp_tbl->lq_type,
896 		       tmp_tbl->ant_type, tmp_tbl->is_SGI);
897 		tmp_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
898 		D_RATE("search- lq:%x, ant:%x, SGI:%d\n", tmp_tbl->lq_type,
899 		       tmp_tbl->ant_type, tmp_tbl->is_SGI);
900 		D_RATE("actual- lq:%x, ant:%x, SGI:%d\n", tbl_type.lq_type,
901 		       tbl_type.ant_type, tbl_type.is_SGI);
902 		/*
903 		 * no matching table found, let's by-pass the data collection
904 		 * and continue to perform rate scale to find the rate table
905 		 */
906 		il4965_rs_stay_in_table(lq_sta, true);
907 		goto done;
908 	}
909 
910 	/*
911 	 * Updating the frame history depends on whether packets were
912 	 * aggregated.
913 	 *
914 	 * For aggregation, all packets were transmitted at the same rate, the
915 	 * first idx into rate scale table.
916 	 */
917 	if (info->flags & IEEE80211_TX_STAT_AMPDU) {
918 		tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
919 		il4965_rs_get_tbl_info_from_mcs(tx_rate, il->band, &tbl_type,
920 						&rs_idx);
921 		il4965_rs_collect_tx_data(curr_tbl, rs_idx,
922 					  info->status.ampdu_len,
923 					  info->status.ampdu_ack_len);
924 
925 		/* Update success/fail counts if not searching for new mode */
926 		if (lq_sta->stay_in_tbl) {
927 			lq_sta->total_success += info->status.ampdu_ack_len;
928 			lq_sta->total_failed +=
929 			    (info->status.ampdu_len -
930 			     info->status.ampdu_ack_len);
931 		}
932 	} else {
933 		/*
934 		 * For legacy, update frame history with for each Tx retry.
935 		 */
936 		retries = info->status.rates[0].count - 1;
937 		/* HW doesn't send more than 15 retries */
938 		retries = min(retries, 15);
939 
940 		/* The last transmission may have been successful */
941 		legacy_success = !!(info->flags & IEEE80211_TX_STAT_ACK);
942 		/* Collect data for each rate used during failed TX attempts */
943 		for (i = 0; i <= retries; ++i) {
944 			tx_rate = le32_to_cpu(table->rs_table[i].rate_n_flags);
945 			il4965_rs_get_tbl_info_from_mcs(tx_rate, il->band,
946 							&tbl_type, &rs_idx);
947 			/*
948 			 * Only collect stats if retried rate is in the same RS
949 			 * table as active/search.
950 			 */
951 			if (il4965_table_type_matches(&tbl_type, curr_tbl))
952 				tmp_tbl = curr_tbl;
953 			else if (il4965_table_type_matches
954 				 (&tbl_type, other_tbl))
955 				tmp_tbl = other_tbl;
956 			else
957 				continue;
958 			il4965_rs_collect_tx_data(tmp_tbl, rs_idx, 1,
959 						  i <
960 						  retries ? 0 : legacy_success);
961 		}
962 
963 		/* Update success/fail counts if not searching for new mode */
964 		if (lq_sta->stay_in_tbl) {
965 			lq_sta->total_success += legacy_success;
966 			lq_sta->total_failed += retries + (1 - legacy_success);
967 		}
968 	}
969 	/* The last TX rate is cached in lq_sta; it's set in if/else above */
970 	lq_sta->last_rate_n_flags = tx_rate;
971 done:
972 	/* See if there's a better rate or modulation mode to try. */
973 	if (sta->supp_rates[sband->band])
974 		il4965_rs_rate_scale_perform(il, skb, sta, lq_sta);
975 }
976 
977 /*
978  * Begin a period of staying with a selected modulation mode.
979  * Set "stay_in_tbl" flag to prevent any mode switches.
980  * Set frame tx success limits according to legacy vs. high-throughput,
981  * and reset overall (spanning all rates) tx success history stats.
982  * These control how long we stay using same modulation mode before
983  * searching for a new mode.
984  */
985 static void
986 il4965_rs_set_stay_in_table(struct il_priv *il, u8 is_legacy,
987 			    struct il_lq_sta *lq_sta)
988 {
989 	D_RATE("we are staying in the same table\n");
990 	lq_sta->stay_in_tbl = 1;	/* only place this gets set */
991 	if (is_legacy) {
992 		lq_sta->table_count_limit = IL_LEGACY_TBL_COUNT;
993 		lq_sta->max_failure_limit = IL_LEGACY_FAILURE_LIMIT;
994 		lq_sta->max_success_limit = IL_LEGACY_SUCCESS_LIMIT;
995 	} else {
996 		lq_sta->table_count_limit = IL_NONE_LEGACY_TBL_COUNT;
997 		lq_sta->max_failure_limit = IL_NONE_LEGACY_FAILURE_LIMIT;
998 		lq_sta->max_success_limit = IL_NONE_LEGACY_SUCCESS_LIMIT;
999 	}
1000 	lq_sta->table_count = 0;
1001 	lq_sta->total_failed = 0;
1002 	lq_sta->total_success = 0;
1003 	lq_sta->flush_timer = jiffies;
1004 	lq_sta->action_counter = 0;
1005 }
1006 
1007 /*
1008  * Find correct throughput table for given mode of modulation
1009  */
1010 static void
1011 il4965_rs_set_expected_tpt_table(struct il_lq_sta *lq_sta,
1012 				 struct il_scale_tbl_info *tbl)
1013 {
1014 	/* Used to choose among HT tables */
1015 	s32(*ht_tbl_pointer)[RATE_COUNT];
1016 
1017 	/* Check for invalid LQ type */
1018 	if (WARN_ON_ONCE(!is_legacy(tbl->lq_type) && !is_Ht(tbl->lq_type))) {
1019 		tbl->expected_tpt = expected_tpt_legacy;
1020 		return;
1021 	}
1022 
1023 	/* Legacy rates have only one table */
1024 	if (is_legacy(tbl->lq_type)) {
1025 		tbl->expected_tpt = expected_tpt_legacy;
1026 		return;
1027 	}
1028 
1029 	/* Choose among many HT tables depending on number of streams
1030 	 * (SISO/MIMO2), channel width (20/40), SGI, and aggregation
1031 	 * status */
1032 	if (is_siso(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
1033 		ht_tbl_pointer = expected_tpt_siso20MHz;
1034 	else if (is_siso(tbl->lq_type))
1035 		ht_tbl_pointer = expected_tpt_siso40MHz;
1036 	else if (is_mimo2(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
1037 		ht_tbl_pointer = expected_tpt_mimo2_20MHz;
1038 	else			/* if (is_mimo2(tbl->lq_type)) <-- must be true */
1039 		ht_tbl_pointer = expected_tpt_mimo2_40MHz;
1040 
1041 	if (!tbl->is_SGI && !lq_sta->is_agg)	/* Normal */
1042 		tbl->expected_tpt = ht_tbl_pointer[0];
1043 	else if (tbl->is_SGI && !lq_sta->is_agg)	/* SGI */
1044 		tbl->expected_tpt = ht_tbl_pointer[1];
1045 	else if (!tbl->is_SGI && lq_sta->is_agg)	/* AGG */
1046 		tbl->expected_tpt = ht_tbl_pointer[2];
1047 	else			/* AGG+SGI */
1048 		tbl->expected_tpt = ht_tbl_pointer[3];
1049 }
1050 
1051 /*
1052  * Find starting rate for new "search" high-throughput mode of modulation.
1053  * Goal is to find lowest expected rate (under perfect conditions) that is
1054  * above the current measured throughput of "active" mode, to give new mode
1055  * a fair chance to prove itself without too many challenges.
1056  *
1057  * This gets called when transitioning to more aggressive modulation
1058  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1059  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1060  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1061  * bit rate will typically need to increase, but not if performance was bad.
1062  */
1063 static s32
1064 il4965_rs_get_best_rate(struct il_priv *il, struct il_lq_sta *lq_sta,
1065 			struct il_scale_tbl_info *tbl,	/* "search" */
1066 			u16 rate_mask, s8 idx)
1067 {
1068 	/* "active" values */
1069 	struct il_scale_tbl_info *active_tbl =
1070 	    &(lq_sta->lq_info[lq_sta->active_tbl]);
1071 	s32 active_sr = active_tbl->win[idx].success_ratio;
1072 	s32 active_tpt = active_tbl->expected_tpt[idx];
1073 
1074 	/* expected "search" throughput */
1075 	s32 *tpt_tbl = tbl->expected_tpt;
1076 
1077 	s32 new_rate, high, low, start_hi;
1078 	u16 high_low;
1079 	s8 rate = idx;
1080 
1081 	new_rate = high = low = start_hi = RATE_INVALID;
1082 
1083 	for (;;) {
1084 		high_low =
1085 		    il4965_rs_get_adjacent_rate(il, rate, rate_mask,
1086 						tbl->lq_type);
1087 
1088 		low = high_low & 0xff;
1089 		high = (high_low >> 8) & 0xff;
1090 
1091 		/*
1092 		 * Lower the "search" bit rate, to give new "search" mode
1093 		 * approximately the same throughput as "active" if:
1094 		 *
1095 		 * 1) "Active" mode has been working modestly well (but not
1096 		 *    great), and expected "search" throughput (under perfect
1097 		 *    conditions) at candidate rate is above the actual
1098 		 *    measured "active" throughput (but less than expected
1099 		 *    "active" throughput under perfect conditions).
1100 		 * OR
1101 		 * 2) "Active" mode has been working perfectly or very well
1102 		 *    and expected "search" throughput (under perfect
1103 		 *    conditions) at candidate rate is above expected
1104 		 *    "active" throughput (under perfect conditions).
1105 		 */
1106 		if ((100 * tpt_tbl[rate] > lq_sta->last_tpt &&
1107 		     (active_sr > RATE_DECREASE_TH && active_sr <= RATE_HIGH_TH
1108 		      && tpt_tbl[rate] <= active_tpt)) ||
1109 		    (active_sr >= RATE_SCALE_SWITCH &&
1110 		     tpt_tbl[rate] > active_tpt)) {
1111 
1112 			/* (2nd or later pass)
1113 			 * If we've already tried to raise the rate, and are
1114 			 * now trying to lower it, use the higher rate. */
1115 			if (start_hi != RATE_INVALID) {
1116 				new_rate = start_hi;
1117 				break;
1118 			}
1119 
1120 			new_rate = rate;
1121 
1122 			/* Loop again with lower rate */
1123 			if (low != RATE_INVALID)
1124 				rate = low;
1125 
1126 			/* Lower rate not available, use the original */
1127 			else
1128 				break;
1129 
1130 			/* Else try to raise the "search" rate to match "active" */
1131 		} else {
1132 			/* (2nd or later pass)
1133 			 * If we've already tried to lower the rate, and are
1134 			 * now trying to raise it, use the lower rate. */
1135 			if (new_rate != RATE_INVALID)
1136 				break;
1137 
1138 			/* Loop again with higher rate */
1139 			else if (high != RATE_INVALID) {
1140 				start_hi = high;
1141 				rate = high;
1142 
1143 				/* Higher rate not available, use the original */
1144 			} else {
1145 				new_rate = rate;
1146 				break;
1147 			}
1148 		}
1149 	}
1150 
1151 	return new_rate;
1152 }
1153 
1154 /*
1155  * Set up search table for MIMO2
1156  */
1157 static int
1158 il4965_rs_switch_to_mimo2(struct il_priv *il, struct il_lq_sta *lq_sta,
1159 			  struct ieee80211_conf *conf,
1160 			  struct ieee80211_sta *sta,
1161 			  struct il_scale_tbl_info *tbl, int idx)
1162 {
1163 	u16 rate_mask;
1164 	s32 rate;
1165 	s8 is_green = lq_sta->is_green;
1166 
1167 	if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1168 		return -1;
1169 
1170 	if (sta->smps_mode == IEEE80211_SMPS_STATIC)
1171 		return -1;
1172 
1173 	/* Need both Tx chains/antennas to support MIMO */
1174 	if (il->hw_params.tx_chains_num < 2)
1175 		return -1;
1176 
1177 	D_RATE("LQ: try to switch to MIMO2\n");
1178 
1179 	tbl->lq_type = LQ_MIMO2;
1180 	tbl->is_dup = lq_sta->is_dup;
1181 	tbl->action = 0;
1182 	tbl->max_search = IL_MAX_SEARCH;
1183 	rate_mask = lq_sta->active_mimo2_rate;
1184 
1185 	if (il_is_ht40_tx_allowed(il, &sta->ht_cap))
1186 		tbl->is_ht40 = 1;
1187 	else
1188 		tbl->is_ht40 = 0;
1189 
1190 	il4965_rs_set_expected_tpt_table(lq_sta, tbl);
1191 
1192 	rate = il4965_rs_get_best_rate(il, lq_sta, tbl, rate_mask, idx);
1193 
1194 	D_RATE("LQ: MIMO2 best rate %d mask %X\n", rate, rate_mask);
1195 	if (rate == RATE_INVALID || !((1 << rate) & rate_mask)) {
1196 		D_RATE("Can't switch with idx %d rate mask %x\n", rate,
1197 		       rate_mask);
1198 		return -1;
1199 	}
1200 	tbl->current_rate =
1201 	    il4965_rate_n_flags_from_tbl(il, tbl, rate, is_green);
1202 
1203 	D_RATE("LQ: Switch to new mcs %X idx is green %X\n", tbl->current_rate,
1204 	       is_green);
1205 	return 0;
1206 }
1207 
1208 /*
1209  * Set up search table for SISO
1210  */
1211 static int
1212 il4965_rs_switch_to_siso(struct il_priv *il, struct il_lq_sta *lq_sta,
1213 			 struct ieee80211_conf *conf, struct ieee80211_sta *sta,
1214 			 struct il_scale_tbl_info *tbl, int idx)
1215 {
1216 	u16 rate_mask;
1217 	u8 is_green = lq_sta->is_green;
1218 	s32 rate;
1219 
1220 	if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1221 		return -1;
1222 
1223 	D_RATE("LQ: try to switch to SISO\n");
1224 
1225 	tbl->is_dup = lq_sta->is_dup;
1226 	tbl->lq_type = LQ_SISO;
1227 	tbl->action = 0;
1228 	tbl->max_search = IL_MAX_SEARCH;
1229 	rate_mask = lq_sta->active_siso_rate;
1230 
1231 	if (il_is_ht40_tx_allowed(il, &sta->ht_cap))
1232 		tbl->is_ht40 = 1;
1233 	else
1234 		tbl->is_ht40 = 0;
1235 
1236 	if (is_green)
1237 		tbl->is_SGI = 0;	/*11n spec: no SGI in SISO+Greenfield */
1238 
1239 	il4965_rs_set_expected_tpt_table(lq_sta, tbl);
1240 	rate = il4965_rs_get_best_rate(il, lq_sta, tbl, rate_mask, idx);
1241 
1242 	D_RATE("LQ: get best rate %d mask %X\n", rate, rate_mask);
1243 	if (rate == RATE_INVALID || !((1 << rate) & rate_mask)) {
1244 		D_RATE("can not switch with idx %d rate mask %x\n", rate,
1245 		       rate_mask);
1246 		return -1;
1247 	}
1248 	tbl->current_rate =
1249 	    il4965_rate_n_flags_from_tbl(il, tbl, rate, is_green);
1250 	D_RATE("LQ: Switch to new mcs %X idx is green %X\n", tbl->current_rate,
1251 	       is_green);
1252 	return 0;
1253 }
1254 
1255 /*
1256  * Try to switch to new modulation mode from legacy
1257  */
1258 static int
1259 il4965_rs_move_legacy_other(struct il_priv *il, struct il_lq_sta *lq_sta,
1260 			    struct ieee80211_conf *conf,
1261 			    struct ieee80211_sta *sta, int idx)
1262 {
1263 	struct il_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1264 	struct il_scale_tbl_info *search_tbl =
1265 	    &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1266 	struct il_rate_scale_data *win = &(tbl->win[idx]);
1267 	u32 sz =
1268 	    (sizeof(struct il_scale_tbl_info) -
1269 	     (sizeof(struct il_rate_scale_data) * RATE_COUNT));
1270 	u8 start_action;
1271 	u8 valid_tx_ant = il->hw_params.valid_tx_ant;
1272 	u8 tx_chains_num = il->hw_params.tx_chains_num;
1273 	int ret = 0;
1274 	u8 update_search_tbl_counter = 0;
1275 
1276 	tbl->action = IL_LEGACY_SWITCH_SISO;
1277 
1278 	start_action = tbl->action;
1279 	for (;;) {
1280 		lq_sta->action_counter++;
1281 		switch (tbl->action) {
1282 		case IL_LEGACY_SWITCH_ANTENNA1:
1283 		case IL_LEGACY_SWITCH_ANTENNA2:
1284 			D_RATE("LQ: Legacy toggle Antenna\n");
1285 
1286 			if ((tbl->action == IL_LEGACY_SWITCH_ANTENNA1 &&
1287 			     tx_chains_num <= 1) ||
1288 			    (tbl->action == IL_LEGACY_SWITCH_ANTENNA2 &&
1289 			     tx_chains_num <= 2))
1290 				break;
1291 
1292 			/* Don't change antenna if success has been great */
1293 			if (win->success_ratio >= IL_RS_GOOD_RATIO)
1294 				break;
1295 
1296 			/* Set up search table to try other antenna */
1297 			memcpy(search_tbl, tbl, sz);
1298 
1299 			if (il4965_rs_toggle_antenna
1300 			    (valid_tx_ant, &search_tbl->current_rate,
1301 			     search_tbl)) {
1302 				update_search_tbl_counter = 1;
1303 				il4965_rs_set_expected_tpt_table(lq_sta,
1304 								 search_tbl);
1305 				goto out;
1306 			}
1307 			break;
1308 		case IL_LEGACY_SWITCH_SISO:
1309 			D_RATE("LQ: Legacy switch to SISO\n");
1310 
1311 			/* Set up search table to try SISO */
1312 			memcpy(search_tbl, tbl, sz);
1313 			search_tbl->is_SGI = 0;
1314 			ret =
1315 			    il4965_rs_switch_to_siso(il, lq_sta, conf, sta,
1316 						     search_tbl, idx);
1317 			if (!ret) {
1318 				lq_sta->action_counter = 0;
1319 				goto out;
1320 			}
1321 
1322 			break;
1323 		case IL_LEGACY_SWITCH_MIMO2_AB:
1324 		case IL_LEGACY_SWITCH_MIMO2_AC:
1325 		case IL_LEGACY_SWITCH_MIMO2_BC:
1326 			D_RATE("LQ: Legacy switch to MIMO2\n");
1327 
1328 			/* Set up search table to try MIMO */
1329 			memcpy(search_tbl, tbl, sz);
1330 			search_tbl->is_SGI = 0;
1331 
1332 			if (tbl->action == IL_LEGACY_SWITCH_MIMO2_AB)
1333 				search_tbl->ant_type = ANT_AB;
1334 			else if (tbl->action == IL_LEGACY_SWITCH_MIMO2_AC)
1335 				search_tbl->ant_type = ANT_AC;
1336 			else
1337 				search_tbl->ant_type = ANT_BC;
1338 
1339 			if (!il4965_rs_is_valid_ant
1340 			    (valid_tx_ant, search_tbl->ant_type))
1341 				break;
1342 
1343 			ret =
1344 			    il4965_rs_switch_to_mimo2(il, lq_sta, conf, sta,
1345 						      search_tbl, idx);
1346 			if (!ret) {
1347 				lq_sta->action_counter = 0;
1348 				goto out;
1349 			}
1350 			break;
1351 		}
1352 		tbl->action++;
1353 		if (tbl->action > IL_LEGACY_SWITCH_MIMO2_BC)
1354 			tbl->action = IL_LEGACY_SWITCH_ANTENNA1;
1355 
1356 		if (tbl->action == start_action)
1357 			break;
1358 
1359 	}
1360 	search_tbl->lq_type = LQ_NONE;
1361 	return 0;
1362 
1363 out:
1364 	lq_sta->search_better_tbl = 1;
1365 	tbl->action++;
1366 	if (tbl->action > IL_LEGACY_SWITCH_MIMO2_BC)
1367 		tbl->action = IL_LEGACY_SWITCH_ANTENNA1;
1368 	if (update_search_tbl_counter)
1369 		search_tbl->action = tbl->action;
1370 	return 0;
1371 
1372 }
1373 
1374 /*
1375  * Try to switch to new modulation mode from SISO
1376  */
1377 static int
1378 il4965_rs_move_siso_to_other(struct il_priv *il, struct il_lq_sta *lq_sta,
1379 			     struct ieee80211_conf *conf,
1380 			     struct ieee80211_sta *sta, int idx)
1381 {
1382 	u8 is_green = lq_sta->is_green;
1383 	struct il_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1384 	struct il_scale_tbl_info *search_tbl =
1385 	    &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1386 	struct il_rate_scale_data *win = &(tbl->win[idx]);
1387 	struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1388 	u32 sz =
1389 	    (sizeof(struct il_scale_tbl_info) -
1390 	     (sizeof(struct il_rate_scale_data) * RATE_COUNT));
1391 	u8 start_action;
1392 	u8 valid_tx_ant = il->hw_params.valid_tx_ant;
1393 	u8 tx_chains_num = il->hw_params.tx_chains_num;
1394 	u8 update_search_tbl_counter = 0;
1395 	int ret;
1396 
1397 	start_action = tbl->action;
1398 
1399 	for (;;) {
1400 		lq_sta->action_counter++;
1401 		switch (tbl->action) {
1402 		case IL_SISO_SWITCH_ANTENNA1:
1403 		case IL_SISO_SWITCH_ANTENNA2:
1404 			D_RATE("LQ: SISO toggle Antenna\n");
1405 			if ((tbl->action == IL_SISO_SWITCH_ANTENNA1 &&
1406 			     tx_chains_num <= 1) ||
1407 			    (tbl->action == IL_SISO_SWITCH_ANTENNA2 &&
1408 			     tx_chains_num <= 2))
1409 				break;
1410 
1411 			if (win->success_ratio >= IL_RS_GOOD_RATIO)
1412 				break;
1413 
1414 			memcpy(search_tbl, tbl, sz);
1415 			if (il4965_rs_toggle_antenna
1416 			    (valid_tx_ant, &search_tbl->current_rate,
1417 			     search_tbl)) {
1418 				update_search_tbl_counter = 1;
1419 				goto out;
1420 			}
1421 			break;
1422 		case IL_SISO_SWITCH_MIMO2_AB:
1423 		case IL_SISO_SWITCH_MIMO2_AC:
1424 		case IL_SISO_SWITCH_MIMO2_BC:
1425 			D_RATE("LQ: SISO switch to MIMO2\n");
1426 			memcpy(search_tbl, tbl, sz);
1427 			search_tbl->is_SGI = 0;
1428 
1429 			if (tbl->action == IL_SISO_SWITCH_MIMO2_AB)
1430 				search_tbl->ant_type = ANT_AB;
1431 			else if (tbl->action == IL_SISO_SWITCH_MIMO2_AC)
1432 				search_tbl->ant_type = ANT_AC;
1433 			else
1434 				search_tbl->ant_type = ANT_BC;
1435 
1436 			if (!il4965_rs_is_valid_ant
1437 			    (valid_tx_ant, search_tbl->ant_type))
1438 				break;
1439 
1440 			ret =
1441 			    il4965_rs_switch_to_mimo2(il, lq_sta, conf, sta,
1442 						      search_tbl, idx);
1443 			if (!ret)
1444 				goto out;
1445 			break;
1446 		case IL_SISO_SWITCH_GI:
1447 			if (!tbl->is_ht40 &&
1448 			    !(ht_cap->cap & IEEE80211_HT_CAP_SGI_20))
1449 				break;
1450 			if (tbl->is_ht40 &&
1451 			    !(ht_cap->cap & IEEE80211_HT_CAP_SGI_40))
1452 				break;
1453 
1454 			D_RATE("LQ: SISO toggle SGI/NGI\n");
1455 
1456 			memcpy(search_tbl, tbl, sz);
1457 			if (is_green) {
1458 				if (!tbl->is_SGI)
1459 					break;
1460 				else
1461 					IL_ERR("SGI was set in GF+SISO\n");
1462 			}
1463 			search_tbl->is_SGI = !tbl->is_SGI;
1464 			il4965_rs_set_expected_tpt_table(lq_sta, search_tbl);
1465 			if (tbl->is_SGI) {
1466 				s32 tpt = lq_sta->last_tpt / 100;
1467 				if (tpt >= search_tbl->expected_tpt[idx])
1468 					break;
1469 			}
1470 			search_tbl->current_rate =
1471 			    il4965_rate_n_flags_from_tbl(il, search_tbl, idx,
1472 							 is_green);
1473 			update_search_tbl_counter = 1;
1474 			goto out;
1475 		}
1476 		tbl->action++;
1477 		if (tbl->action > IL_SISO_SWITCH_GI)
1478 			tbl->action = IL_SISO_SWITCH_ANTENNA1;
1479 
1480 		if (tbl->action == start_action)
1481 			break;
1482 	}
1483 	search_tbl->lq_type = LQ_NONE;
1484 	return 0;
1485 
1486 out:
1487 	lq_sta->search_better_tbl = 1;
1488 	tbl->action++;
1489 	if (tbl->action > IL_SISO_SWITCH_GI)
1490 		tbl->action = IL_SISO_SWITCH_ANTENNA1;
1491 	if (update_search_tbl_counter)
1492 		search_tbl->action = tbl->action;
1493 
1494 	return 0;
1495 }
1496 
1497 /*
1498  * Try to switch to new modulation mode from MIMO2
1499  */
1500 static int
1501 il4965_rs_move_mimo2_to_other(struct il_priv *il, struct il_lq_sta *lq_sta,
1502 			      struct ieee80211_conf *conf,
1503 			      struct ieee80211_sta *sta, int idx)
1504 {
1505 	s8 is_green = lq_sta->is_green;
1506 	struct il_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1507 	struct il_scale_tbl_info *search_tbl =
1508 	    &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1509 	struct il_rate_scale_data *win = &(tbl->win[idx]);
1510 	struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1511 	u32 sz =
1512 	    (sizeof(struct il_scale_tbl_info) -
1513 	     (sizeof(struct il_rate_scale_data) * RATE_COUNT));
1514 	u8 start_action;
1515 	u8 valid_tx_ant = il->hw_params.valid_tx_ant;
1516 	u8 tx_chains_num = il->hw_params.tx_chains_num;
1517 	u8 update_search_tbl_counter = 0;
1518 	int ret;
1519 
1520 	start_action = tbl->action;
1521 	for (;;) {
1522 		lq_sta->action_counter++;
1523 		switch (tbl->action) {
1524 		case IL_MIMO2_SWITCH_ANTENNA1:
1525 		case IL_MIMO2_SWITCH_ANTENNA2:
1526 			D_RATE("LQ: MIMO2 toggle Antennas\n");
1527 
1528 			if (tx_chains_num <= 2)
1529 				break;
1530 
1531 			if (win->success_ratio >= IL_RS_GOOD_RATIO)
1532 				break;
1533 
1534 			memcpy(search_tbl, tbl, sz);
1535 			if (il4965_rs_toggle_antenna
1536 			    (valid_tx_ant, &search_tbl->current_rate,
1537 			     search_tbl)) {
1538 				update_search_tbl_counter = 1;
1539 				goto out;
1540 			}
1541 			break;
1542 		case IL_MIMO2_SWITCH_SISO_A:
1543 		case IL_MIMO2_SWITCH_SISO_B:
1544 		case IL_MIMO2_SWITCH_SISO_C:
1545 			D_RATE("LQ: MIMO2 switch to SISO\n");
1546 
1547 			/* Set up new search table for SISO */
1548 			memcpy(search_tbl, tbl, sz);
1549 
1550 			if (tbl->action == IL_MIMO2_SWITCH_SISO_A)
1551 				search_tbl->ant_type = ANT_A;
1552 			else if (tbl->action == IL_MIMO2_SWITCH_SISO_B)
1553 				search_tbl->ant_type = ANT_B;
1554 			else
1555 				search_tbl->ant_type = ANT_C;
1556 
1557 			if (!il4965_rs_is_valid_ant
1558 			    (valid_tx_ant, search_tbl->ant_type))
1559 				break;
1560 
1561 			ret =
1562 			    il4965_rs_switch_to_siso(il, lq_sta, conf, sta,
1563 						     search_tbl, idx);
1564 			if (!ret)
1565 				goto out;
1566 
1567 			break;
1568 
1569 		case IL_MIMO2_SWITCH_GI:
1570 			if (!tbl->is_ht40 &&
1571 			    !(ht_cap->cap & IEEE80211_HT_CAP_SGI_20))
1572 				break;
1573 			if (tbl->is_ht40 &&
1574 			    !(ht_cap->cap & IEEE80211_HT_CAP_SGI_40))
1575 				break;
1576 
1577 			D_RATE("LQ: MIMO2 toggle SGI/NGI\n");
1578 
1579 			/* Set up new search table for MIMO2 */
1580 			memcpy(search_tbl, tbl, sz);
1581 			search_tbl->is_SGI = !tbl->is_SGI;
1582 			il4965_rs_set_expected_tpt_table(lq_sta, search_tbl);
1583 			/*
1584 			 * If active table already uses the fastest possible
1585 			 * modulation (dual stream with short guard interval),
1586 			 * and it's working well, there's no need to look
1587 			 * for a better type of modulation!
1588 			 */
1589 			if (tbl->is_SGI) {
1590 				s32 tpt = lq_sta->last_tpt / 100;
1591 				if (tpt >= search_tbl->expected_tpt[idx])
1592 					break;
1593 			}
1594 			search_tbl->current_rate =
1595 			    il4965_rate_n_flags_from_tbl(il, search_tbl, idx,
1596 							 is_green);
1597 			update_search_tbl_counter = 1;
1598 			goto out;
1599 
1600 		}
1601 		tbl->action++;
1602 		if (tbl->action > IL_MIMO2_SWITCH_GI)
1603 			tbl->action = IL_MIMO2_SWITCH_ANTENNA1;
1604 
1605 		if (tbl->action == start_action)
1606 			break;
1607 	}
1608 	search_tbl->lq_type = LQ_NONE;
1609 	return 0;
1610 out:
1611 	lq_sta->search_better_tbl = 1;
1612 	tbl->action++;
1613 	if (tbl->action > IL_MIMO2_SWITCH_GI)
1614 		tbl->action = IL_MIMO2_SWITCH_ANTENNA1;
1615 	if (update_search_tbl_counter)
1616 		search_tbl->action = tbl->action;
1617 
1618 	return 0;
1619 
1620 }
1621 
1622 /*
1623  * Check whether we should continue using same modulation mode, or
1624  * begin search for a new mode, based on:
1625  * 1) # tx successes or failures while using this mode
1626  * 2) # times calling this function
1627  * 3) elapsed time in this mode (not used, for now)
1628  */
1629 static void
1630 il4965_rs_stay_in_table(struct il_lq_sta *lq_sta, bool force_search)
1631 {
1632 	struct il_scale_tbl_info *tbl;
1633 	int i;
1634 	int active_tbl;
1635 	int flush_interval_passed = 0;
1636 	struct il_priv *il;
1637 
1638 	il = lq_sta->drv;
1639 	active_tbl = lq_sta->active_tbl;
1640 
1641 	tbl = &(lq_sta->lq_info[active_tbl]);
1642 
1643 	/* If we've been disallowing search, see if we should now allow it */
1644 	if (lq_sta->stay_in_tbl) {
1645 
1646 		/* Elapsed time using current modulation mode */
1647 		if (lq_sta->flush_timer)
1648 			flush_interval_passed =
1649 			    time_after(jiffies,
1650 				       (unsigned long)(lq_sta->flush_timer +
1651 						       RATE_SCALE_FLUSH_INTVL));
1652 
1653 		/*
1654 		 * Check if we should allow search for new modulation mode.
1655 		 * If many frames have failed or succeeded, or we've used
1656 		 * this same modulation for a long time, allow search, and
1657 		 * reset history stats that keep track of whether we should
1658 		 * allow a new search.  Also (below) reset all bitmaps and
1659 		 * stats in active history.
1660 		 */
1661 		if (force_search ||
1662 		    lq_sta->total_failed > lq_sta->max_failure_limit ||
1663 		    lq_sta->total_success > lq_sta->max_success_limit ||
1664 		    (!lq_sta->search_better_tbl && lq_sta->flush_timer &&
1665 		     flush_interval_passed)) {
1666 			D_RATE("LQ: stay is expired %d %d %d\n",
1667 			       lq_sta->total_failed, lq_sta->total_success,
1668 			       flush_interval_passed);
1669 
1670 			/* Allow search for new mode */
1671 			lq_sta->stay_in_tbl = 0;	/* only place reset */
1672 			lq_sta->total_failed = 0;
1673 			lq_sta->total_success = 0;
1674 			lq_sta->flush_timer = 0;
1675 
1676 			/*
1677 			 * Else if we've used this modulation mode enough repetitions
1678 			 * (regardless of elapsed time or success/failure), reset
1679 			 * history bitmaps and rate-specific stats for all rates in
1680 			 * active table.
1681 			 */
1682 		} else {
1683 			lq_sta->table_count++;
1684 			if (lq_sta->table_count >= lq_sta->table_count_limit) {
1685 				lq_sta->table_count = 0;
1686 
1687 				D_RATE("LQ: stay in table clear win\n");
1688 				for (i = 0; i < RATE_COUNT; i++)
1689 					il4965_rs_rate_scale_clear_win(&
1690 								       (tbl->
1691 									win
1692 									[i]));
1693 			}
1694 		}
1695 
1696 		/* If transitioning to allow "search", reset all history
1697 		 * bitmaps and stats in active table (this will become the new
1698 		 * "search" table). */
1699 		if (!lq_sta->stay_in_tbl) {
1700 			for (i = 0; i < RATE_COUNT; i++)
1701 				il4965_rs_rate_scale_clear_win(&(tbl->win[i]));
1702 		}
1703 	}
1704 }
1705 
1706 /*
1707  * setup rate table in uCode
1708  */
1709 static void
1710 il4965_rs_update_rate_tbl(struct il_priv *il, struct il_lq_sta *lq_sta,
1711 			  struct il_scale_tbl_info *tbl, int idx, u8 is_green)
1712 {
1713 	u32 rate;
1714 
1715 	/* Update uCode's rate table. */
1716 	rate = il4965_rate_n_flags_from_tbl(il, tbl, idx, is_green);
1717 	il4965_rs_fill_link_cmd(il, lq_sta, rate);
1718 	il_send_lq_cmd(il, &lq_sta->lq, CMD_ASYNC, false);
1719 }
1720 
1721 /*
1722  * Do rate scaling and search for new modulation mode.
1723  */
1724 static void
1725 il4965_rs_rate_scale_perform(struct il_priv *il, struct sk_buff *skb,
1726 			     struct ieee80211_sta *sta,
1727 			     struct il_lq_sta *lq_sta)
1728 {
1729 	struct ieee80211_hw *hw = il->hw;
1730 	struct ieee80211_conf *conf = &hw->conf;
1731 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1732 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1733 	int low = RATE_INVALID;
1734 	int high = RATE_INVALID;
1735 	int idx;
1736 	int i;
1737 	struct il_rate_scale_data *win = NULL;
1738 	int current_tpt = IL_INVALID_VALUE;
1739 	int low_tpt = IL_INVALID_VALUE;
1740 	int high_tpt = IL_INVALID_VALUE;
1741 	u32 fail_count;
1742 	s8 scale_action = 0;
1743 	u16 rate_mask;
1744 	u8 update_lq = 0;
1745 	struct il_scale_tbl_info *tbl, *tbl1;
1746 	u16 rate_scale_idx_msk = 0;
1747 	u8 is_green = 0;
1748 	u8 active_tbl = 0;
1749 	u8 done_search = 0;
1750 	u16 high_low;
1751 	s32 sr;
1752 	u8 tid = MAX_TID_COUNT;
1753 	struct il_tid_data *tid_data;
1754 
1755 	D_RATE("rate scale calculate new rate for skb\n");
1756 
1757 	/* Send management frames and NO_ACK data using lowest rate. */
1758 	/* TODO: this could probably be improved.. */
1759 	if (!ieee80211_is_data(hdr->frame_control) ||
1760 	    (info->flags & IEEE80211_TX_CTL_NO_ACK))
1761 		return;
1762 
1763 	lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
1764 
1765 	tid = il4965_rs_tl_add_packet(lq_sta, hdr);
1766 	if (tid != MAX_TID_COUNT && (lq_sta->tx_agg_tid_en & (1 << tid))) {
1767 		tid_data = &il->stations[lq_sta->lq.sta_id].tid[tid];
1768 		if (tid_data->agg.state == IL_AGG_OFF)
1769 			lq_sta->is_agg = 0;
1770 		else
1771 			lq_sta->is_agg = 1;
1772 	} else
1773 		lq_sta->is_agg = 0;
1774 
1775 	/*
1776 	 * Select rate-scale / modulation-mode table to work with in
1777 	 * the rest of this function:  "search" if searching for better
1778 	 * modulation mode, or "active" if doing rate scaling within a mode.
1779 	 */
1780 	if (!lq_sta->search_better_tbl)
1781 		active_tbl = lq_sta->active_tbl;
1782 	else
1783 		active_tbl = 1 - lq_sta->active_tbl;
1784 
1785 	tbl = &(lq_sta->lq_info[active_tbl]);
1786 	if (is_legacy(tbl->lq_type))
1787 		lq_sta->is_green = 0;
1788 	else
1789 		lq_sta->is_green = il4965_rs_use_green(il, sta);
1790 	is_green = lq_sta->is_green;
1791 
1792 	/* current tx rate */
1793 	idx = lq_sta->last_txrate_idx;
1794 
1795 	D_RATE("Rate scale idx %d for type %d\n", idx, tbl->lq_type);
1796 
1797 	/* rates available for this association, and for modulation mode */
1798 	rate_mask = il4965_rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
1799 
1800 	D_RATE("mask 0x%04X\n", rate_mask);
1801 
1802 	/* mask with station rate restriction */
1803 	if (is_legacy(tbl->lq_type)) {
1804 		if (lq_sta->band == NL80211_BAND_5GHZ)
1805 			/* supp_rates has no CCK bits in A mode */
1806 			rate_scale_idx_msk =
1807 			    (u16) (rate_mask &
1808 				   (lq_sta->supp_rates << IL_FIRST_OFDM_RATE));
1809 		else
1810 			rate_scale_idx_msk =
1811 			    (u16) (rate_mask & lq_sta->supp_rates);
1812 
1813 	} else
1814 		rate_scale_idx_msk = rate_mask;
1815 
1816 	if (!rate_scale_idx_msk)
1817 		rate_scale_idx_msk = rate_mask;
1818 
1819 	if (!((1 << idx) & rate_scale_idx_msk)) {
1820 		IL_ERR("Current Rate is not valid\n");
1821 		if (lq_sta->search_better_tbl) {
1822 			/* revert to active table if search table is not valid */
1823 			tbl->lq_type = LQ_NONE;
1824 			lq_sta->search_better_tbl = 0;
1825 			tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1826 			/* get "active" rate info */
1827 			idx = il4965_hwrate_to_plcp_idx(tbl->current_rate);
1828 			il4965_rs_update_rate_tbl(il, lq_sta, tbl, idx,
1829 						      is_green);
1830 		}
1831 		return;
1832 	}
1833 
1834 	/* Get expected throughput table and history win for current rate */
1835 	if (!tbl->expected_tpt) {
1836 		IL_ERR("tbl->expected_tpt is NULL\n");
1837 		return;
1838 	}
1839 
1840 	/* force user max rate if set by user */
1841 	if (lq_sta->max_rate_idx != -1 && lq_sta->max_rate_idx < idx) {
1842 		idx = lq_sta->max_rate_idx;
1843 		update_lq = 1;
1844 		win = &(tbl->win[idx]);
1845 		goto lq_update;
1846 	}
1847 
1848 	win = &(tbl->win[idx]);
1849 
1850 	/*
1851 	 * If there is not enough history to calculate actual average
1852 	 * throughput, keep analyzing results of more tx frames, without
1853 	 * changing rate or mode (bypass most of the rest of this function).
1854 	 * Set up new rate table in uCode only if old rate is not supported
1855 	 * in current association (use new rate found above).
1856 	 */
1857 	fail_count = win->counter - win->success_counter;
1858 	if (fail_count < RATE_MIN_FAILURE_TH &&
1859 	    win->success_counter < RATE_MIN_SUCCESS_TH) {
1860 		D_RATE("LQ: still below TH. succ=%d total=%d " "for idx %d\n",
1861 		       win->success_counter, win->counter, idx);
1862 
1863 		/* Can't calculate this yet; not enough history */
1864 		win->average_tpt = IL_INVALID_VALUE;
1865 
1866 		/* Should we stay with this modulation mode,
1867 		 * or search for a new one? */
1868 		il4965_rs_stay_in_table(lq_sta, false);
1869 
1870 		goto out;
1871 	}
1872 	/* Else we have enough samples; calculate estimate of
1873 	 * actual average throughput */
1874 	if (win->average_tpt !=
1875 	    ((win->success_ratio * tbl->expected_tpt[idx] + 64) / 128)) {
1876 		IL_ERR("expected_tpt should have been calculated by now\n");
1877 		win->average_tpt =
1878 		    ((win->success_ratio * tbl->expected_tpt[idx] + 64) / 128);
1879 	}
1880 
1881 	/* If we are searching for better modulation mode, check success. */
1882 	if (lq_sta->search_better_tbl) {
1883 		/* If good success, continue using the "search" mode;
1884 		 * no need to send new link quality command, since we're
1885 		 * continuing to use the setup that we've been trying. */
1886 		if (win->average_tpt > lq_sta->last_tpt) {
1887 
1888 			D_RATE("LQ: SWITCHING TO NEW TBL "
1889 			       "suc=%d cur-tpt=%d old-tpt=%d\n",
1890 			       win->success_ratio, win->average_tpt,
1891 			       lq_sta->last_tpt);
1892 
1893 			if (!is_legacy(tbl->lq_type))
1894 				lq_sta->enable_counter = 1;
1895 
1896 			/* Swap tables; "search" becomes "active" */
1897 			lq_sta->active_tbl = active_tbl;
1898 			current_tpt = win->average_tpt;
1899 
1900 			/* Else poor success; go back to mode in "active" table */
1901 		} else {
1902 
1903 			D_RATE("LQ: GOING BACK TO THE OLD TBL "
1904 			       "suc=%d cur-tpt=%d old-tpt=%d\n",
1905 			       win->success_ratio, win->average_tpt,
1906 			       lq_sta->last_tpt);
1907 
1908 			/* Nullify "search" table */
1909 			tbl->lq_type = LQ_NONE;
1910 
1911 			/* Revert to "active" table */
1912 			active_tbl = lq_sta->active_tbl;
1913 			tbl = &(lq_sta->lq_info[active_tbl]);
1914 
1915 			/* Revert to "active" rate and throughput info */
1916 			idx = il4965_hwrate_to_plcp_idx(tbl->current_rate);
1917 			current_tpt = lq_sta->last_tpt;
1918 
1919 			/* Need to set up a new rate table in uCode */
1920 			update_lq = 1;
1921 		}
1922 
1923 		/* Either way, we've made a decision; modulation mode
1924 		 * search is done, allow rate adjustment next time. */
1925 		lq_sta->search_better_tbl = 0;
1926 		done_search = 1;	/* Don't switch modes below! */
1927 		goto lq_update;
1928 	}
1929 
1930 	/* (Else) not in search of better modulation mode, try for better
1931 	 * starting rate, while staying in this mode. */
1932 	high_low =
1933 	    il4965_rs_get_adjacent_rate(il, idx, rate_scale_idx_msk,
1934 					tbl->lq_type);
1935 	low = high_low & 0xff;
1936 	high = (high_low >> 8) & 0xff;
1937 
1938 	/* If user set max rate, dont allow higher than user constrain */
1939 	if (lq_sta->max_rate_idx != -1 && lq_sta->max_rate_idx < high)
1940 		high = RATE_INVALID;
1941 
1942 	sr = win->success_ratio;
1943 
1944 	/* Collect measured throughputs for current and adjacent rates */
1945 	current_tpt = win->average_tpt;
1946 	if (low != RATE_INVALID)
1947 		low_tpt = tbl->win[low].average_tpt;
1948 	if (high != RATE_INVALID)
1949 		high_tpt = tbl->win[high].average_tpt;
1950 
1951 	scale_action = 0;
1952 
1953 	/* Too many failures, decrease rate */
1954 	if (sr <= RATE_DECREASE_TH || current_tpt == 0) {
1955 		D_RATE("decrease rate because of low success_ratio\n");
1956 		scale_action = -1;
1957 
1958 		/* No throughput measured yet for adjacent rates; try increase. */
1959 	} else if (low_tpt == IL_INVALID_VALUE && high_tpt == IL_INVALID_VALUE) {
1960 
1961 		if (high != RATE_INVALID && sr >= RATE_INCREASE_TH)
1962 			scale_action = 1;
1963 		else if (low != RATE_INVALID)
1964 			scale_action = 0;
1965 	}
1966 
1967 	/* Both adjacent throughputs are measured, but neither one has better
1968 	 * throughput; we're using the best rate, don't change it! */
1969 	else if (low_tpt != IL_INVALID_VALUE && high_tpt != IL_INVALID_VALUE &&
1970 		 low_tpt < current_tpt && high_tpt < current_tpt)
1971 		scale_action = 0;
1972 
1973 	/* At least one adjacent rate's throughput is measured,
1974 	 * and may have better performance. */
1975 	else {
1976 		/* Higher adjacent rate's throughput is measured */
1977 		if (high_tpt != IL_INVALID_VALUE) {
1978 			/* Higher rate has better throughput */
1979 			if (high_tpt > current_tpt && sr >= RATE_INCREASE_TH)
1980 				scale_action = 1;
1981 			else
1982 				scale_action = 0;
1983 
1984 			/* Lower adjacent rate's throughput is measured */
1985 		} else if (low_tpt != IL_INVALID_VALUE) {
1986 			/* Lower rate has better throughput */
1987 			if (low_tpt > current_tpt) {
1988 				D_RATE("decrease rate because of low tpt\n");
1989 				scale_action = -1;
1990 			} else if (sr >= RATE_INCREASE_TH) {
1991 				scale_action = 1;
1992 			}
1993 		}
1994 	}
1995 
1996 	/* Sanity check; asked for decrease, but success rate or throughput
1997 	 * has been good at old rate.  Don't change it. */
1998 	if (scale_action == -1 && low != RATE_INVALID &&
1999 	    (sr > RATE_HIGH_TH || current_tpt > 100 * tbl->expected_tpt[low]))
2000 		scale_action = 0;
2001 
2002 	switch (scale_action) {
2003 	case -1:
2004 		/* Decrease starting rate, update uCode's rate table */
2005 		if (low != RATE_INVALID) {
2006 			update_lq = 1;
2007 			idx = low;
2008 		}
2009 
2010 		break;
2011 	case 1:
2012 		/* Increase starting rate, update uCode's rate table */
2013 		if (high != RATE_INVALID) {
2014 			update_lq = 1;
2015 			idx = high;
2016 		}
2017 
2018 		break;
2019 	case 0:
2020 		/* No change */
2021 	default:
2022 		break;
2023 	}
2024 
2025 	D_RATE("choose rate scale idx %d action %d low %d " "high %d type %d\n",
2026 	       idx, scale_action, low, high, tbl->lq_type);
2027 
2028 lq_update:
2029 	/* Replace uCode's rate table for the destination station. */
2030 	if (update_lq)
2031 		il4965_rs_update_rate_tbl(il, lq_sta, tbl, idx, is_green);
2032 
2033 	/* Should we stay with this modulation mode,
2034 	 * or search for a new one? */
2035 	il4965_rs_stay_in_table(lq_sta, false);
2036 
2037 	/*
2038 	 * Search for new modulation mode if we're:
2039 	 * 1)  Not changing rates right now
2040 	 * 2)  Not just finishing up a search
2041 	 * 3)  Allowing a new search
2042 	 */
2043 	if (!update_lq && !done_search && !lq_sta->stay_in_tbl && win->counter) {
2044 		/* Save current throughput to compare with "search" throughput */
2045 		lq_sta->last_tpt = current_tpt;
2046 
2047 		/* Select a new "search" modulation mode to try.
2048 		 * If one is found, set up the new "search" table. */
2049 		if (is_legacy(tbl->lq_type))
2050 			il4965_rs_move_legacy_other(il, lq_sta, conf, sta, idx);
2051 		else if (is_siso(tbl->lq_type))
2052 			il4965_rs_move_siso_to_other(il, lq_sta, conf, sta,
2053 						     idx);
2054 		else		/* (is_mimo2(tbl->lq_type)) */
2055 			il4965_rs_move_mimo2_to_other(il, lq_sta, conf, sta,
2056 						      idx);
2057 
2058 		/* If new "search" mode was selected, set up in uCode table */
2059 		if (lq_sta->search_better_tbl) {
2060 			/* Access the "search" table, clear its history. */
2061 			tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
2062 			for (i = 0; i < RATE_COUNT; i++)
2063 				il4965_rs_rate_scale_clear_win(&(tbl->win[i]));
2064 
2065 			/* Use new "search" start rate */
2066 			idx = il4965_hwrate_to_plcp_idx(tbl->current_rate);
2067 
2068 			D_RATE("Switch current  mcs: %X idx: %d\n",
2069 			       tbl->current_rate, idx);
2070 			il4965_rs_fill_link_cmd(il, lq_sta, tbl->current_rate);
2071 			il_send_lq_cmd(il, &lq_sta->lq, CMD_ASYNC, false);
2072 		} else
2073 			done_search = 1;
2074 	}
2075 
2076 	if (done_search && !lq_sta->stay_in_tbl) {
2077 		/* If the "active" (non-search) mode was legacy,
2078 		 * and we've tried switching antennas,
2079 		 * but we haven't been able to try HT modes (not available),
2080 		 * stay with best antenna legacy modulation for a while
2081 		 * before next round of mode comparisons. */
2082 		tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
2083 		if (is_legacy(tbl1->lq_type) && !conf_is_ht(conf) &&
2084 		    lq_sta->action_counter > tbl1->max_search) {
2085 			D_RATE("LQ: STAY in legacy table\n");
2086 			il4965_rs_set_stay_in_table(il, 1, lq_sta);
2087 		}
2088 
2089 		/* If we're in an HT mode, and all 3 mode switch actions
2090 		 * have been tried and compared, stay in this best modulation
2091 		 * mode for a while before next round of mode comparisons. */
2092 		if (lq_sta->enable_counter &&
2093 		    lq_sta->action_counter >= tbl1->max_search) {
2094 			if (lq_sta->last_tpt > IL_AGG_TPT_THREHOLD &&
2095 			    (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2096 			    tid != MAX_TID_COUNT) {
2097 				tid_data =
2098 				    &il->stations[lq_sta->lq.sta_id].tid[tid];
2099 				if (tid_data->agg.state == IL_AGG_OFF) {
2100 					D_RATE("try to aggregate tid %d\n",
2101 					       tid);
2102 					il4965_rs_tl_turn_on_agg(il, tid,
2103 								 lq_sta, sta);
2104 				}
2105 			}
2106 			il4965_rs_set_stay_in_table(il, 0, lq_sta);
2107 		}
2108 	}
2109 
2110 out:
2111 	tbl->current_rate =
2112 	    il4965_rate_n_flags_from_tbl(il, tbl, idx, is_green);
2113 	i = idx;
2114 	lq_sta->last_txrate_idx = i;
2115 }
2116 
2117 /**
2118  * il4965_rs_initialize_lq - Initialize a station's hardware rate table
2119  *
2120  * The uCode's station table contains a table of fallback rates
2121  * for automatic fallback during transmission.
2122  *
2123  * NOTE: This sets up a default set of values.  These will be replaced later
2124  *       if the driver's iwl-4965-rs rate scaling algorithm is used, instead of
2125  *       rc80211_simple.
2126  *
2127  * NOTE: Run C_ADD_STA command to set up station table entry, before
2128  *       calling this function (which runs C_TX_LINK_QUALITY_CMD,
2129  *       which requires station table entry to exist).
2130  */
2131 static void
2132 il4965_rs_initialize_lq(struct il_priv *il, struct ieee80211_conf *conf,
2133 			struct ieee80211_sta *sta, struct il_lq_sta *lq_sta)
2134 {
2135 	struct il_scale_tbl_info *tbl;
2136 	int rate_idx;
2137 	int i;
2138 	u32 rate;
2139 	u8 use_green;
2140 	u8 active_tbl = 0;
2141 	u8 valid_tx_ant;
2142 
2143 	if (!sta || !lq_sta)
2144 		return;
2145 
2146 	use_green = il4965_rs_use_green(il, sta);
2147 
2148 	i = lq_sta->last_txrate_idx;
2149 
2150 	valid_tx_ant = il->hw_params.valid_tx_ant;
2151 
2152 	if (!lq_sta->search_better_tbl)
2153 		active_tbl = lq_sta->active_tbl;
2154 	else
2155 		active_tbl = 1 - lq_sta->active_tbl;
2156 
2157 	tbl = &(lq_sta->lq_info[active_tbl]);
2158 
2159 	if (i < 0 || i >= RATE_COUNT)
2160 		i = 0;
2161 
2162 	rate = il_rates[i].plcp;
2163 	tbl->ant_type = il4965_first_antenna(valid_tx_ant);
2164 	rate |= tbl->ant_type << RATE_MCS_ANT_POS;
2165 
2166 	if (i >= IL_FIRST_CCK_RATE && i <= IL_LAST_CCK_RATE)
2167 		rate |= RATE_MCS_CCK_MSK;
2168 
2169 	il4965_rs_get_tbl_info_from_mcs(rate, il->band, tbl, &rate_idx);
2170 	if (!il4965_rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2171 		il4965_rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2172 
2173 	rate = il4965_rate_n_flags_from_tbl(il, tbl, rate_idx, use_green);
2174 	tbl->current_rate = rate;
2175 	il4965_rs_set_expected_tpt_table(lq_sta, tbl);
2176 	il4965_rs_fill_link_cmd(NULL, lq_sta, rate);
2177 	il->stations[lq_sta->lq.sta_id].lq = &lq_sta->lq;
2178 	il_send_lq_cmd(il, &lq_sta->lq, CMD_SYNC, true);
2179 }
2180 
2181 static void
2182 il4965_rs_get_rate(void *il_r, struct ieee80211_sta *sta, void *il_sta,
2183 		   struct ieee80211_tx_rate_control *txrc)
2184 {
2185 
2186 	struct sk_buff *skb = txrc->skb;
2187 	struct ieee80211_supported_band *sband = txrc->sband;
2188 	struct il_priv *il __maybe_unused = (struct il_priv *)il_r;
2189 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2190 	struct il_lq_sta *lq_sta = il_sta;
2191 	int rate_idx;
2192 
2193 	D_RATE("rate scale calculate new rate for skb\n");
2194 
2195 	/* Get max rate if user set max rate */
2196 	if (lq_sta) {
2197 		lq_sta->max_rate_idx = fls(txrc->rate_idx_mask) - 1;
2198 		if (sband->band == NL80211_BAND_5GHZ &&
2199 		    lq_sta->max_rate_idx != -1)
2200 			lq_sta->max_rate_idx += IL_FIRST_OFDM_RATE;
2201 		if (lq_sta->max_rate_idx < 0 ||
2202 		    lq_sta->max_rate_idx >= RATE_COUNT)
2203 			lq_sta->max_rate_idx = -1;
2204 	}
2205 
2206 	/* Treat uninitialized rate scaling data same as non-existing. */
2207 	if (lq_sta && !lq_sta->drv) {
2208 		D_RATE("Rate scaling not initialized yet.\n");
2209 		il_sta = NULL;
2210 	}
2211 
2212 	if (!lq_sta)
2213 		return;
2214 
2215 	rate_idx = lq_sta->last_txrate_idx;
2216 
2217 	if (lq_sta->last_rate_n_flags & RATE_MCS_HT_MSK) {
2218 		rate_idx -= IL_FIRST_OFDM_RATE;
2219 		/* 6M and 9M shared same MCS idx */
2220 		rate_idx = (rate_idx > 0) ? (rate_idx - 1) : 0;
2221 		if (il4965_rs_extract_rate(lq_sta->last_rate_n_flags) >=
2222 		    RATE_MIMO2_6M_PLCP)
2223 			rate_idx = rate_idx + MCS_IDX_PER_STREAM;
2224 		info->control.rates[0].flags = IEEE80211_TX_RC_MCS;
2225 		if (lq_sta->last_rate_n_flags & RATE_MCS_SGI_MSK)
2226 			info->control.rates[0].flags |=
2227 			    IEEE80211_TX_RC_SHORT_GI;
2228 		if (lq_sta->last_rate_n_flags & RATE_MCS_DUP_MSK)
2229 			info->control.rates[0].flags |=
2230 			    IEEE80211_TX_RC_DUP_DATA;
2231 		if (lq_sta->last_rate_n_flags & RATE_MCS_HT40_MSK)
2232 			info->control.rates[0].flags |=
2233 			    IEEE80211_TX_RC_40_MHZ_WIDTH;
2234 		if (lq_sta->last_rate_n_flags & RATE_MCS_GF_MSK)
2235 			info->control.rates[0].flags |=
2236 			    IEEE80211_TX_RC_GREEN_FIELD;
2237 	} else {
2238 		/* Check for invalid rates */
2239 		if (rate_idx < 0 || rate_idx >= RATE_COUNT_LEGACY ||
2240 		    (sband->band == NL80211_BAND_5GHZ &&
2241 		     rate_idx < IL_FIRST_OFDM_RATE))
2242 			rate_idx = rate_lowest_index(sband, sta);
2243 		/* On valid 5 GHz rate, adjust idx */
2244 		else if (sband->band == NL80211_BAND_5GHZ)
2245 			rate_idx -= IL_FIRST_OFDM_RATE;
2246 		info->control.rates[0].flags = 0;
2247 	}
2248 	info->control.rates[0].idx = rate_idx;
2249 	info->control.rates[0].count = 1;
2250 }
2251 
2252 static void *
2253 il4965_rs_alloc_sta(void *il_rate, struct ieee80211_sta *sta, gfp_t gfp)
2254 {
2255 	struct il_station_priv *sta_priv =
2256 	    (struct il_station_priv *)sta->drv_priv;
2257 	struct il_priv *il;
2258 
2259 	il = (struct il_priv *)il_rate;
2260 	D_RATE("create station rate scale win\n");
2261 
2262 	return &sta_priv->lq_sta;
2263 }
2264 
2265 /*
2266  * Called after adding a new station to initialize rate scaling
2267  */
2268 void
2269 il4965_rs_rate_init(struct il_priv *il, struct ieee80211_sta *sta, u8 sta_id)
2270 {
2271 	int i, j;
2272 	struct ieee80211_hw *hw = il->hw;
2273 	struct ieee80211_conf *conf = &il->hw->conf;
2274 	struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
2275 	struct il_station_priv *sta_priv;
2276 	struct il_lq_sta *lq_sta;
2277 	struct ieee80211_supported_band *sband;
2278 
2279 	sta_priv = (struct il_station_priv *)sta->drv_priv;
2280 	lq_sta = &sta_priv->lq_sta;
2281 	sband = hw->wiphy->bands[conf->chandef.chan->band];
2282 
2283 	lq_sta->lq.sta_id = sta_id;
2284 
2285 	for (j = 0; j < LQ_SIZE; j++)
2286 		for (i = 0; i < RATE_COUNT; i++)
2287 			il4965_rs_rate_scale_clear_win(&lq_sta->lq_info[j].
2288 						       win[i]);
2289 
2290 	lq_sta->flush_timer = 0;
2291 	lq_sta->supp_rates = sta->supp_rates[sband->band];
2292 	for (j = 0; j < LQ_SIZE; j++)
2293 		for (i = 0; i < RATE_COUNT; i++)
2294 			il4965_rs_rate_scale_clear_win(&lq_sta->lq_info[j].
2295 						       win[i]);
2296 
2297 	D_RATE("LQ:" "*** rate scale station global init for station %d ***\n",
2298 	       sta_id);
2299 	/* TODO: what is a good starting rate for STA? About middle? Maybe not
2300 	 * the lowest or the highest rate.. Could consider using RSSI from
2301 	 * previous packets? Need to have IEEE 802.1X auth succeed immediately
2302 	 * after assoc.. */
2303 
2304 	lq_sta->is_dup = 0;
2305 	lq_sta->max_rate_idx = -1;
2306 	lq_sta->missed_rate_counter = IL_MISSED_RATE_MAX;
2307 	lq_sta->is_green = il4965_rs_use_green(il, sta);
2308 	lq_sta->active_legacy_rate = il->active_rate & ~(0x1000);
2309 	lq_sta->band = il->band;
2310 	/*
2311 	 * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2312 	 * supp_rates[] does not; shift to convert format, force 9 MBits off.
2313 	 */
2314 	lq_sta->active_siso_rate = ht_cap->mcs.rx_mask[0] << 1;
2315 	lq_sta->active_siso_rate |= ht_cap->mcs.rx_mask[0] & 0x1;
2316 	lq_sta->active_siso_rate &= ~((u16) 0x2);
2317 	lq_sta->active_siso_rate <<= IL_FIRST_OFDM_RATE;
2318 
2319 	/* Same here */
2320 	lq_sta->active_mimo2_rate = ht_cap->mcs.rx_mask[1] << 1;
2321 	lq_sta->active_mimo2_rate |= ht_cap->mcs.rx_mask[1] & 0x1;
2322 	lq_sta->active_mimo2_rate &= ~((u16) 0x2);
2323 	lq_sta->active_mimo2_rate <<= IL_FIRST_OFDM_RATE;
2324 
2325 	/* These values will be overridden later */
2326 	lq_sta->lq.general_params.single_stream_ant_msk =
2327 	    il4965_first_antenna(il->hw_params.valid_tx_ant);
2328 	lq_sta->lq.general_params.dual_stream_ant_msk =
2329 	    il->hw_params.valid_tx_ant & ~il4965_first_antenna(il->hw_params.
2330 							       valid_tx_ant);
2331 	if (!lq_sta->lq.general_params.dual_stream_ant_msk) {
2332 		lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2333 	} else if (il4965_num_of_ant(il->hw_params.valid_tx_ant) == 2) {
2334 		lq_sta->lq.general_params.dual_stream_ant_msk =
2335 		    il->hw_params.valid_tx_ant;
2336 	}
2337 
2338 	/* as default allow aggregation for all tids */
2339 	lq_sta->tx_agg_tid_en = IL_AGG_ALL_TID;
2340 	lq_sta->drv = il;
2341 
2342 	/* Set last_txrate_idx to lowest rate */
2343 	lq_sta->last_txrate_idx = rate_lowest_index(sband, sta);
2344 	if (sband->band == NL80211_BAND_5GHZ)
2345 		lq_sta->last_txrate_idx += IL_FIRST_OFDM_RATE;
2346 	lq_sta->is_agg = 0;
2347 
2348 #ifdef CONFIG_MAC80211_DEBUGFS
2349 	lq_sta->dbg_fixed_rate = 0;
2350 #endif
2351 
2352 	il4965_rs_initialize_lq(il, conf, sta, lq_sta);
2353 }
2354 
2355 static void
2356 il4965_rs_fill_link_cmd(struct il_priv *il, struct il_lq_sta *lq_sta,
2357 			u32 new_rate)
2358 {
2359 	struct il_scale_tbl_info tbl_type;
2360 	int idx = 0;
2361 	int rate_idx;
2362 	int repeat_rate = 0;
2363 	u8 ant_toggle_cnt = 0;
2364 	u8 use_ht_possible = 1;
2365 	u8 valid_tx_ant = 0;
2366 	struct il_link_quality_cmd *lq_cmd = &lq_sta->lq;
2367 
2368 	/* Override starting rate (idx 0) if needed for debug purposes */
2369 	il4965_rs_dbgfs_set_mcs(lq_sta, &new_rate, idx);
2370 
2371 	/* Interpret new_rate (rate_n_flags) */
2372 	il4965_rs_get_tbl_info_from_mcs(new_rate, lq_sta->band, &tbl_type,
2373 					&rate_idx);
2374 
2375 	/* How many times should we repeat the initial rate? */
2376 	if (is_legacy(tbl_type.lq_type)) {
2377 		ant_toggle_cnt = 1;
2378 		repeat_rate = IL_NUMBER_TRY;
2379 	} else {
2380 		repeat_rate = IL_HT_NUMBER_TRY;
2381 	}
2382 
2383 	lq_cmd->general_params.mimo_delimiter =
2384 	    is_mimo(tbl_type.lq_type) ? 1 : 0;
2385 
2386 	/* Fill 1st table entry (idx 0) */
2387 	lq_cmd->rs_table[idx].rate_n_flags = cpu_to_le32(new_rate);
2388 
2389 	if (il4965_num_of_ant(tbl_type.ant_type) == 1) {
2390 		lq_cmd->general_params.single_stream_ant_msk =
2391 		    tbl_type.ant_type;
2392 	} else if (il4965_num_of_ant(tbl_type.ant_type) == 2) {
2393 		lq_cmd->general_params.dual_stream_ant_msk = tbl_type.ant_type;
2394 	}
2395 	/* otherwise we don't modify the existing value */
2396 	idx++;
2397 	repeat_rate--;
2398 	if (il)
2399 		valid_tx_ant = il->hw_params.valid_tx_ant;
2400 
2401 	/* Fill rest of rate table */
2402 	while (idx < LINK_QUAL_MAX_RETRY_NUM) {
2403 		/* Repeat initial/next rate.
2404 		 * For legacy IL_NUMBER_TRY == 1, this loop will not execute.
2405 		 * For HT IL_HT_NUMBER_TRY == 3, this executes twice. */
2406 		while (repeat_rate > 0 && idx < LINK_QUAL_MAX_RETRY_NUM) {
2407 			if (is_legacy(tbl_type.lq_type)) {
2408 				if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2409 					ant_toggle_cnt++;
2410 				else if (il &&
2411 					 il4965_rs_toggle_antenna(valid_tx_ant,
2412 								  &new_rate,
2413 								  &tbl_type))
2414 					ant_toggle_cnt = 1;
2415 			}
2416 
2417 			/* Override next rate if needed for debug purposes */
2418 			il4965_rs_dbgfs_set_mcs(lq_sta, &new_rate, idx);
2419 
2420 			/* Fill next table entry */
2421 			lq_cmd->rs_table[idx].rate_n_flags =
2422 			    cpu_to_le32(new_rate);
2423 			repeat_rate--;
2424 			idx++;
2425 		}
2426 
2427 		il4965_rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2428 						&tbl_type, &rate_idx);
2429 
2430 		/* Indicate to uCode which entries might be MIMO.
2431 		 * If initial rate was MIMO, this will finally end up
2432 		 * as (IL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2433 		if (is_mimo(tbl_type.lq_type))
2434 			lq_cmd->general_params.mimo_delimiter = idx;
2435 
2436 		/* Get next rate */
2437 		new_rate =
2438 		    il4965_rs_get_lower_rate(lq_sta, &tbl_type, rate_idx,
2439 					     use_ht_possible);
2440 
2441 		/* How many times should we repeat the next rate? */
2442 		if (is_legacy(tbl_type.lq_type)) {
2443 			if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2444 				ant_toggle_cnt++;
2445 			else if (il &&
2446 				 il4965_rs_toggle_antenna(valid_tx_ant,
2447 							  &new_rate, &tbl_type))
2448 				ant_toggle_cnt = 1;
2449 
2450 			repeat_rate = IL_NUMBER_TRY;
2451 		} else {
2452 			repeat_rate = IL_HT_NUMBER_TRY;
2453 		}
2454 
2455 		/* Don't allow HT rates after next pass.
2456 		 * il4965_rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2457 		use_ht_possible = 0;
2458 
2459 		/* Override next rate if needed for debug purposes */
2460 		il4965_rs_dbgfs_set_mcs(lq_sta, &new_rate, idx);
2461 
2462 		/* Fill next table entry */
2463 		lq_cmd->rs_table[idx].rate_n_flags = cpu_to_le32(new_rate);
2464 
2465 		idx++;
2466 		repeat_rate--;
2467 	}
2468 
2469 	lq_cmd->agg_params.agg_frame_cnt_limit = LINK_QUAL_AGG_FRAME_LIMIT_DEF;
2470 	lq_cmd->agg_params.agg_dis_start_th = LINK_QUAL_AGG_DISABLE_START_DEF;
2471 
2472 	lq_cmd->agg_params.agg_time_limit =
2473 	    cpu_to_le16(LINK_QUAL_AGG_TIME_LIMIT_DEF);
2474 }
2475 
2476 static void *
2477 il4965_rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
2478 {
2479 	return hw->priv;
2480 }
2481 
2482 /* rate scale requires free function to be implemented */
2483 static void
2484 il4965_rs_free(void *il_rate)
2485 {
2486 	return;
2487 }
2488 
2489 static void
2490 il4965_rs_free_sta(void *il_r, struct ieee80211_sta *sta, void *il_sta)
2491 {
2492 	struct il_priv *il __maybe_unused = il_r;
2493 
2494 	D_RATE("enter\n");
2495 	D_RATE("leave\n");
2496 }
2497 
2498 #ifdef CONFIG_MAC80211_DEBUGFS
2499 
2500 static void
2501 il4965_rs_dbgfs_set_mcs(struct il_lq_sta *lq_sta, u32 * rate_n_flags, int idx)
2502 {
2503 	struct il_priv *il;
2504 	u8 valid_tx_ant;
2505 	u8 ant_sel_tx;
2506 
2507 	il = lq_sta->drv;
2508 	valid_tx_ant = il->hw_params.valid_tx_ant;
2509 	if (lq_sta->dbg_fixed_rate) {
2510 		ant_sel_tx =
2511 		    ((lq_sta->
2512 		      dbg_fixed_rate & RATE_MCS_ANT_ABC_MSK) >>
2513 		     RATE_MCS_ANT_POS);
2514 		if ((valid_tx_ant & ant_sel_tx) == ant_sel_tx) {
2515 			*rate_n_flags = lq_sta->dbg_fixed_rate;
2516 			D_RATE("Fixed rate ON\n");
2517 		} else {
2518 			lq_sta->dbg_fixed_rate = 0;
2519 			IL_ERR
2520 			    ("Invalid antenna selection 0x%X, Valid is 0x%X\n",
2521 			     ant_sel_tx, valid_tx_ant);
2522 			D_RATE("Fixed rate OFF\n");
2523 		}
2524 	} else {
2525 		D_RATE("Fixed rate OFF\n");
2526 	}
2527 }
2528 
2529 static ssize_t
2530 il4965_rs_sta_dbgfs_scale_table_write(struct file *file,
2531 				      const char __user *user_buf,
2532 				      size_t count, loff_t *ppos)
2533 {
2534 	struct il_lq_sta *lq_sta = file->private_data;
2535 	struct il_priv *il;
2536 	char buf[64];
2537 	size_t buf_size;
2538 	u32 parsed_rate;
2539 
2540 	il = lq_sta->drv;
2541 	memset(buf, 0, sizeof(buf));
2542 	buf_size = min(count, sizeof(buf) - 1);
2543 	if (copy_from_user(buf, user_buf, buf_size))
2544 		return -EFAULT;
2545 
2546 	if (sscanf(buf, "%x", &parsed_rate) == 1)
2547 		lq_sta->dbg_fixed_rate = parsed_rate;
2548 	else
2549 		lq_sta->dbg_fixed_rate = 0;
2550 
2551 	lq_sta->active_legacy_rate = 0x0FFF;	/* 1 - 54 MBits, includes CCK */
2552 	lq_sta->active_siso_rate = 0x1FD0;	/* 6 - 60 MBits, no 9, no CCK */
2553 	lq_sta->active_mimo2_rate = 0x1FD0;	/* 6 - 60 MBits, no 9, no CCK */
2554 
2555 	D_RATE("sta_id %d rate 0x%X\n", lq_sta->lq.sta_id,
2556 	       lq_sta->dbg_fixed_rate);
2557 
2558 	if (lq_sta->dbg_fixed_rate) {
2559 		il4965_rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2560 		il_send_lq_cmd(lq_sta->drv, &lq_sta->lq, CMD_ASYNC, false);
2561 	}
2562 
2563 	return count;
2564 }
2565 
2566 static ssize_t
2567 il4965_rs_sta_dbgfs_scale_table_read(struct file *file, char __user *user_buf,
2568 				     size_t count, loff_t *ppos)
2569 {
2570 	char *buff;
2571 	int desc = 0;
2572 	int i = 0;
2573 	int idx = 0;
2574 	ssize_t ret;
2575 
2576 	struct il_lq_sta *lq_sta = file->private_data;
2577 	struct il_priv *il;
2578 	struct il_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2579 
2580 	il = lq_sta->drv;
2581 	buff = kmalloc(1024, GFP_KERNEL);
2582 	if (!buff)
2583 		return -ENOMEM;
2584 
2585 	desc += sprintf(buff + desc, "sta_id %d\n", lq_sta->lq.sta_id);
2586 	desc +=
2587 	    sprintf(buff + desc, "failed=%d success=%d rate=0%X\n",
2588 		    lq_sta->total_failed, lq_sta->total_success,
2589 		    lq_sta->active_legacy_rate);
2590 	desc +=
2591 	    sprintf(buff + desc, "fixed rate 0x%X\n", lq_sta->dbg_fixed_rate);
2592 	desc +=
2593 	    sprintf(buff + desc, "valid_tx_ant %s%s%s\n",
2594 		    (il->hw_params.valid_tx_ant & ANT_A) ? "ANT_A," : "",
2595 		    (il->hw_params.valid_tx_ant & ANT_B) ? "ANT_B," : "",
2596 		    (il->hw_params.valid_tx_ant & ANT_C) ? "ANT_C" : "");
2597 	desc +=
2598 	    sprintf(buff + desc, "lq type %s\n",
2599 		    (is_legacy(tbl->lq_type)) ? "legacy" : "HT");
2600 	if (is_Ht(tbl->lq_type)) {
2601 		desc +=
2602 		    sprintf(buff + desc, " %s",
2603 			    (is_siso(tbl->lq_type)) ? "SISO" : "MIMO2");
2604 		desc +=
2605 		    sprintf(buff + desc, " %s",
2606 			    (tbl->is_ht40) ? "40MHz" : "20MHz");
2607 		desc +=
2608 		    sprintf(buff + desc, " %s %s %s\n",
2609 			    (tbl->is_SGI) ? "SGI" : "",
2610 			    (lq_sta->is_green) ? "GF enabled" : "",
2611 			    (lq_sta->is_agg) ? "AGG on" : "");
2612 	}
2613 	desc +=
2614 	    sprintf(buff + desc, "last tx rate=0x%X\n",
2615 		    lq_sta->last_rate_n_flags);
2616 	desc +=
2617 	    sprintf(buff + desc,
2618 		    "general:" "flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2619 		    lq_sta->lq.general_params.flags,
2620 		    lq_sta->lq.general_params.mimo_delimiter,
2621 		    lq_sta->lq.general_params.single_stream_ant_msk,
2622 		    lq_sta->lq.general_params.dual_stream_ant_msk);
2623 
2624 	desc +=
2625 	    sprintf(buff + desc,
2626 		    "agg:"
2627 		    "time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2628 		    le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2629 		    lq_sta->lq.agg_params.agg_dis_start_th,
2630 		    lq_sta->lq.agg_params.agg_frame_cnt_limit);
2631 
2632 	desc +=
2633 	    sprintf(buff + desc,
2634 		    "Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2635 		    lq_sta->lq.general_params.start_rate_idx[0],
2636 		    lq_sta->lq.general_params.start_rate_idx[1],
2637 		    lq_sta->lq.general_params.start_rate_idx[2],
2638 		    lq_sta->lq.general_params.start_rate_idx[3]);
2639 
2640 	for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++) {
2641 		idx =
2642 		    il4965_hwrate_to_plcp_idx(le32_to_cpu
2643 					      (lq_sta->lq.rs_table[i].
2644 					       rate_n_flags));
2645 		if (is_legacy(tbl->lq_type)) {
2646 			desc +=
2647 			    sprintf(buff + desc, " rate[%d] 0x%X %smbps\n", i,
2648 				    le32_to_cpu(lq_sta->lq.rs_table[i].
2649 						rate_n_flags),
2650 				    il_rate_mcs[idx].mbps);
2651 		} else {
2652 			desc +=
2653 			    sprintf(buff + desc, " rate[%d] 0x%X %smbps (%s)\n",
2654 				    i,
2655 				    le32_to_cpu(lq_sta->lq.rs_table[i].
2656 						rate_n_flags),
2657 				    il_rate_mcs[idx].mbps,
2658 				    il_rate_mcs[idx].mcs);
2659 		}
2660 	}
2661 
2662 	ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2663 	kfree(buff);
2664 	return ret;
2665 }
2666 
2667 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2668 	.write = il4965_rs_sta_dbgfs_scale_table_write,
2669 	.read = il4965_rs_sta_dbgfs_scale_table_read,
2670 	.open = simple_open,
2671 	.llseek = default_llseek,
2672 };
2673 
2674 static ssize_t
2675 il4965_rs_sta_dbgfs_stats_table_read(struct file *file, char __user *user_buf,
2676 				     size_t count, loff_t *ppos)
2677 {
2678 	char *buff;
2679 	int desc = 0;
2680 	int i, j;
2681 	ssize_t ret;
2682 
2683 	struct il_lq_sta *lq_sta = file->private_data;
2684 
2685 	buff = kmalloc(1024, GFP_KERNEL);
2686 	if (!buff)
2687 		return -ENOMEM;
2688 
2689 	for (i = 0; i < LQ_SIZE; i++) {
2690 		desc +=
2691 		    sprintf(buff + desc,
2692 			    "%s type=%d SGI=%d HT40=%d DUP=%d GF=%d\n"
2693 			    "rate=0x%X\n", lq_sta->active_tbl == i ? "*" : "x",
2694 			    lq_sta->lq_info[i].lq_type,
2695 			    lq_sta->lq_info[i].is_SGI,
2696 			    lq_sta->lq_info[i].is_ht40,
2697 			    lq_sta->lq_info[i].is_dup, lq_sta->is_green,
2698 			    lq_sta->lq_info[i].current_rate);
2699 		for (j = 0; j < RATE_COUNT; j++) {
2700 			desc +=
2701 			    sprintf(buff + desc,
2702 				    "counter=%d success=%d %%=%d\n",
2703 				    lq_sta->lq_info[i].win[j].counter,
2704 				    lq_sta->lq_info[i].win[j].success_counter,
2705 				    lq_sta->lq_info[i].win[j].success_ratio);
2706 		}
2707 	}
2708 	ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2709 	kfree(buff);
2710 	return ret;
2711 }
2712 
2713 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
2714 	.read = il4965_rs_sta_dbgfs_stats_table_read,
2715 	.open = simple_open,
2716 	.llseek = default_llseek,
2717 };
2718 
2719 static ssize_t
2720 il4965_rs_sta_dbgfs_rate_scale_data_read(struct file *file,
2721 					 char __user *user_buf, size_t count,
2722 					 loff_t *ppos)
2723 {
2724 	char buff[120];
2725 	int desc = 0;
2726 	struct il_lq_sta *lq_sta = file->private_data;
2727 	struct il_scale_tbl_info *tbl = &lq_sta->lq_info[lq_sta->active_tbl];
2728 
2729 	if (is_Ht(tbl->lq_type))
2730 		desc +=
2731 		    sprintf(buff + desc, "Bit Rate= %d Mb/s\n",
2732 			    tbl->expected_tpt[lq_sta->last_txrate_idx]);
2733 	else
2734 		desc +=
2735 		    sprintf(buff + desc, "Bit Rate= %d Mb/s\n",
2736 			    il_rates[lq_sta->last_txrate_idx].ieee >> 1);
2737 
2738 	return simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2739 }
2740 
2741 static const struct file_operations rs_sta_dbgfs_rate_scale_data_ops = {
2742 	.read = il4965_rs_sta_dbgfs_rate_scale_data_read,
2743 	.open = simple_open,
2744 	.llseek = default_llseek,
2745 };
2746 
2747 static void
2748 il4965_rs_add_debugfs(void *il, void *il_sta, struct dentry *dir)
2749 {
2750 	struct il_lq_sta *lq_sta = il_sta;
2751 
2752 	debugfs_create_file("rate_scale_table", 0600, dir, lq_sta,
2753 			    &rs_sta_dbgfs_scale_table_ops);
2754 	debugfs_create_file("rate_stats_table", 0400, dir, lq_sta,
2755 			    &rs_sta_dbgfs_stats_table_ops);
2756 	debugfs_create_file("rate_scale_data", 0400, dir, lq_sta,
2757 			    &rs_sta_dbgfs_rate_scale_data_ops);
2758 	debugfs_create_u8("tx_agg_tid_enable", 0600, dir,
2759 			  &lq_sta->tx_agg_tid_en);
2760 }
2761 #endif
2762 
2763 /*
2764  * Initialization of rate scaling information is done by driver after
2765  * the station is added. Since mac80211 calls this function before a
2766  * station is added we ignore it.
2767  */
2768 static void
2769 il4965_rs_rate_init_stub(void *il_r, struct ieee80211_supported_band *sband,
2770 			 struct cfg80211_chan_def *chandef,
2771 			 struct ieee80211_sta *sta, void *il_sta)
2772 {
2773 }
2774 
2775 static const struct rate_control_ops rs_4965_ops = {
2776 	.name = IL4965_RS_NAME,
2777 	.tx_status = il4965_rs_tx_status,
2778 	.get_rate = il4965_rs_get_rate,
2779 	.rate_init = il4965_rs_rate_init_stub,
2780 	.alloc = il4965_rs_alloc,
2781 	.free = il4965_rs_free,
2782 	.alloc_sta = il4965_rs_alloc_sta,
2783 	.free_sta = il4965_rs_free_sta,
2784 #ifdef CONFIG_MAC80211_DEBUGFS
2785 	.add_sta_debugfs = il4965_rs_add_debugfs,
2786 #endif
2787 };
2788 
2789 int
2790 il4965_rate_control_register(void)
2791 {
2792 	return ieee80211_rate_control_register(&rs_4965_ops);
2793 }
2794 
2795 void
2796 il4965_rate_control_unregister(void)
2797 {
2798 	ieee80211_rate_control_unregister(&rs_4965_ops);
2799 }
2800