1 /******************************************************************************
2  *
3  * Copyright(c) 2005 - 2011 Intel Corporation. All rights reserved.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of version 2 of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
17  *
18  * The full GNU General Public License is included in this distribution in the
19  * file called LICENSE.
20  *
21  * Contact Information:
22  *  Intel Linux Wireless <ilw@linux.intel.com>
23  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
24  *
25  *****************************************************************************/
26 #include <linux/kernel.h>
27 #include <linux/init.h>
28 #include <linux/skbuff.h>
29 #include <linux/slab.h>
30 #include <linux/wireless.h>
31 #include <net/mac80211.h>
32 
33 #include <linux/netdevice.h>
34 #include <linux/etherdevice.h>
35 #include <linux/delay.h>
36 
37 #include <linux/workqueue.h>
38 
39 #include "iwl-dev.h"
40 #include "iwl-sta.h"
41 #include "iwl-core.h"
42 #include "iwl-4965.h"
43 
44 #define IWL4965_RS_NAME "iwl-4965-rs"
45 
46 #define NUM_TRY_BEFORE_ANT_TOGGLE 1
47 #define IWL_NUMBER_TRY      1
48 #define IWL_HT_NUMBER_TRY   3
49 
50 #define IWL_RATE_MAX_WINDOW		62	/* # tx in history window */
51 #define IWL_RATE_MIN_FAILURE_TH		6	/* min failures to calc tpt */
52 #define IWL_RATE_MIN_SUCCESS_TH		8	/* min successes to calc tpt */
53 
54 /* max allowed rate miss before sync LQ cmd */
55 #define IWL_MISSED_RATE_MAX		15
56 /* max time to accum history 2 seconds */
57 #define IWL_RATE_SCALE_FLUSH_INTVL   (3*HZ)
58 
59 static u8 rs_ht_to_legacy[] = {
60 	IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
61 	IWL_RATE_6M_INDEX, IWL_RATE_6M_INDEX,
62 	IWL_RATE_6M_INDEX,
63 	IWL_RATE_6M_INDEX, IWL_RATE_9M_INDEX,
64 	IWL_RATE_12M_INDEX, IWL_RATE_18M_INDEX,
65 	IWL_RATE_24M_INDEX, IWL_RATE_36M_INDEX,
66 	IWL_RATE_48M_INDEX, IWL_RATE_54M_INDEX
67 };
68 
69 static const u8 ant_toggle_lookup[] = {
70 	/*ANT_NONE -> */ ANT_NONE,
71 	/*ANT_A    -> */ ANT_B,
72 	/*ANT_B    -> */ ANT_C,
73 	/*ANT_AB   -> */ ANT_BC,
74 	/*ANT_C    -> */ ANT_A,
75 	/*ANT_AC   -> */ ANT_AB,
76 	/*ANT_BC   -> */ ANT_AC,
77 	/*ANT_ABC  -> */ ANT_ABC,
78 };
79 
80 #define IWL_DECLARE_RATE_INFO(r, s, ip, in, rp, rn, pp, np)    \
81 	[IWL_RATE_##r##M_INDEX] = { IWL_RATE_##r##M_PLCP,      \
82 				    IWL_RATE_SISO_##s##M_PLCP, \
83 				    IWL_RATE_MIMO2_##s##M_PLCP,\
84 				    IWL_RATE_##r##M_IEEE,      \
85 				    IWL_RATE_##ip##M_INDEX,    \
86 				    IWL_RATE_##in##M_INDEX,    \
87 				    IWL_RATE_##rp##M_INDEX,    \
88 				    IWL_RATE_##rn##M_INDEX,    \
89 				    IWL_RATE_##pp##M_INDEX,    \
90 				    IWL_RATE_##np##M_INDEX }
91 
92 /*
93  * Parameter order:
94  *   rate, ht rate, prev rate, next rate, prev tgg rate, next tgg rate
95  *
96  * If there isn't a valid next or previous rate then INV is used which
97  * maps to IWL_RATE_INVALID
98  *
99  */
100 const struct iwl_rate_info iwlegacy_rates[IWL_RATE_COUNT] = {
101 	IWL_DECLARE_RATE_INFO(1, INV, INV, 2, INV, 2, INV, 2),    /*  1mbps */
102 	IWL_DECLARE_RATE_INFO(2, INV, 1, 5, 1, 5, 1, 5),          /*  2mbps */
103 	IWL_DECLARE_RATE_INFO(5, INV, 2, 6, 2, 11, 2, 11),        /*5.5mbps */
104 	IWL_DECLARE_RATE_INFO(11, INV, 9, 12, 9, 12, 5, 18),      /* 11mbps */
105 	IWL_DECLARE_RATE_INFO(6, 6, 5, 9, 5, 11, 5, 11),        /*  6mbps */
106 	IWL_DECLARE_RATE_INFO(9, 6, 6, 11, 6, 11, 5, 11),       /*  9mbps */
107 	IWL_DECLARE_RATE_INFO(12, 12, 11, 18, 11, 18, 11, 18),   /* 12mbps */
108 	IWL_DECLARE_RATE_INFO(18, 18, 12, 24, 12, 24, 11, 24),   /* 18mbps */
109 	IWL_DECLARE_RATE_INFO(24, 24, 18, 36, 18, 36, 18, 36),   /* 24mbps */
110 	IWL_DECLARE_RATE_INFO(36, 36, 24, 48, 24, 48, 24, 48),   /* 36mbps */
111 	IWL_DECLARE_RATE_INFO(48, 48, 36, 54, 36, 54, 36, 54),   /* 48mbps */
112 	IWL_DECLARE_RATE_INFO(54, 54, 48, INV, 48, INV, 48, INV),/* 54mbps */
113 	IWL_DECLARE_RATE_INFO(60, 60, 48, INV, 48, INV, 48, INV),/* 60mbps */
114 };
115 
iwl4965_hwrate_to_plcp_idx(u32 rate_n_flags)116 static int iwl4965_hwrate_to_plcp_idx(u32 rate_n_flags)
117 {
118 	int idx = 0;
119 
120 	/* HT rate format */
121 	if (rate_n_flags & RATE_MCS_HT_MSK) {
122 		idx = (rate_n_flags & 0xff);
123 
124 		if (idx >= IWL_RATE_MIMO2_6M_PLCP)
125 			idx = idx - IWL_RATE_MIMO2_6M_PLCP;
126 
127 		idx += IWL_FIRST_OFDM_RATE;
128 		/* skip 9M not supported in ht*/
129 		if (idx >= IWL_RATE_9M_INDEX)
130 			idx += 1;
131 		if ((idx >= IWL_FIRST_OFDM_RATE) && (idx <= IWL_LAST_OFDM_RATE))
132 			return idx;
133 
134 	/* legacy rate format, search for match in table */
135 	} else {
136 		for (idx = 0; idx < ARRAY_SIZE(iwlegacy_rates); idx++)
137 			if (iwlegacy_rates[idx].plcp == (rate_n_flags & 0xFF))
138 				return idx;
139 	}
140 
141 	return -1;
142 }
143 
144 static void iwl4965_rs_rate_scale_perform(struct iwl_priv *priv,
145 				   struct sk_buff *skb,
146 				   struct ieee80211_sta *sta,
147 				   struct iwl_lq_sta *lq_sta);
148 static void iwl4965_rs_fill_link_cmd(struct iwl_priv *priv,
149 			     struct iwl_lq_sta *lq_sta, u32 rate_n_flags);
150 static void iwl4965_rs_stay_in_table(struct iwl_lq_sta *lq_sta,
151 					bool force_search);
152 
153 #ifdef CONFIG_MAC80211_DEBUGFS
154 static void iwl4965_rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
155 			     u32 *rate_n_flags, int index);
156 #else
iwl4965_rs_dbgfs_set_mcs(struct iwl_lq_sta * lq_sta,u32 * rate_n_flags,int index)157 static void iwl4965_rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
158 			     u32 *rate_n_flags, int index)
159 {}
160 #endif
161 
162 /**
163  * The following tables contain the expected throughput metrics for all rates
164  *
165  *	1, 2, 5.5, 11, 6, 9, 12, 18, 24, 36, 48, 54, 60 MBits
166  *
167  * where invalid entries are zeros.
168  *
169  * CCK rates are only valid in legacy table and will only be used in G
170  * (2.4 GHz) band.
171  */
172 
173 static s32 expected_tpt_legacy[IWL_RATE_COUNT] = {
174 	7, 13, 35, 58, 40, 57, 72, 98, 121, 154, 177, 186, 0
175 };
176 
177 static s32 expected_tpt_siso20MHz[4][IWL_RATE_COUNT] = {
178 	{0, 0, 0, 0, 42, 0,  76, 102, 124, 158, 183, 193, 202}, /* Norm */
179 	{0, 0, 0, 0, 46, 0,  82, 110, 132, 167, 192, 202, 210}, /* SGI */
180 	{0, 0, 0, 0, 48, 0,  93, 135, 176, 251, 319, 351, 381}, /* AGG */
181 	{0, 0, 0, 0, 53, 0, 102, 149, 193, 275, 348, 381, 413}, /* AGG+SGI */
182 };
183 
184 static s32 expected_tpt_siso40MHz[4][IWL_RATE_COUNT] = {
185 	{0, 0, 0, 0,  77, 0, 127, 160, 184, 220, 242, 250, 257}, /* Norm */
186 	{0, 0, 0, 0,  83, 0, 135, 169, 193, 229, 250, 257, 264}, /* SGI */
187 	{0, 0, 0, 0,  96, 0, 182, 259, 328, 451, 553, 598, 640}, /* AGG */
188 	{0, 0, 0, 0, 106, 0, 199, 282, 357, 487, 593, 640, 683}, /* AGG+SGI */
189 };
190 
191 static s32 expected_tpt_mimo2_20MHz[4][IWL_RATE_COUNT] = {
192 	{0, 0, 0, 0,  74, 0, 123, 155, 179, 213, 235, 243, 250}, /* Norm */
193 	{0, 0, 0, 0,  81, 0, 131, 164, 187, 221, 242, 250, 256}, /* SGI */
194 	{0, 0, 0, 0,  92, 0, 175, 250, 317, 436, 534, 578, 619}, /* AGG */
195 	{0, 0, 0, 0, 102, 0, 192, 273, 344, 470, 573, 619, 660}, /* AGG+SGI*/
196 };
197 
198 static s32 expected_tpt_mimo2_40MHz[4][IWL_RATE_COUNT] = {
199 	{0, 0, 0, 0, 123, 0, 182, 214, 235, 264, 279, 285, 289}, /* Norm */
200 	{0, 0, 0, 0, 131, 0, 191, 222, 242, 270, 284, 289, 293}, /* SGI */
201 	{0, 0, 0, 0, 180, 0, 327, 446, 545, 708, 828, 878, 922}, /* AGG */
202 	{0, 0, 0, 0, 197, 0, 355, 481, 584, 752, 872, 922, 966}, /* AGG+SGI */
203 };
204 
205 /* mbps, mcs */
206 static const struct iwl_rate_mcs_info iwl_rate_mcs[IWL_RATE_COUNT] = {
207 	{  "1", "BPSK DSSS"},
208 	{  "2", "QPSK DSSS"},
209 	{"5.5", "BPSK CCK"},
210 	{ "11", "QPSK CCK"},
211 	{  "6", "BPSK 1/2"},
212 	{  "9", "BPSK 1/2"},
213 	{ "12", "QPSK 1/2"},
214 	{ "18", "QPSK 3/4"},
215 	{ "24", "16QAM 1/2"},
216 	{ "36", "16QAM 3/4"},
217 	{ "48", "64QAM 2/3"},
218 	{ "54", "64QAM 3/4"},
219 	{ "60", "64QAM 5/6"},
220 };
221 
222 #define MCS_INDEX_PER_STREAM	(8)
223 
iwl4965_rs_extract_rate(u32 rate_n_flags)224 static inline u8 iwl4965_rs_extract_rate(u32 rate_n_flags)
225 {
226 	return (u8)(rate_n_flags & 0xFF);
227 }
228 
229 static void
iwl4965_rs_rate_scale_clear_window(struct iwl_rate_scale_data * window)230 iwl4965_rs_rate_scale_clear_window(struct iwl_rate_scale_data *window)
231 {
232 	window->data = 0;
233 	window->success_counter = 0;
234 	window->success_ratio = IWL_INVALID_VALUE;
235 	window->counter = 0;
236 	window->average_tpt = IWL_INVALID_VALUE;
237 	window->stamp = 0;
238 }
239 
iwl4965_rs_is_valid_ant(u8 valid_antenna,u8 ant_type)240 static inline u8 iwl4965_rs_is_valid_ant(u8 valid_antenna, u8 ant_type)
241 {
242 	return (ant_type & valid_antenna) == ant_type;
243 }
244 
245 /*
246  *	removes the old data from the statistics. All data that is older than
247  *	TID_MAX_TIME_DIFF, will be deleted.
248  */
249 static void
iwl4965_rs_tl_rm_old_stats(struct iwl_traffic_load * tl,u32 curr_time)250 iwl4965_rs_tl_rm_old_stats(struct iwl_traffic_load *tl, u32 curr_time)
251 {
252 	/* The oldest age we want to keep */
253 	u32 oldest_time = curr_time - TID_MAX_TIME_DIFF;
254 
255 	while (tl->queue_count &&
256 	       (tl->time_stamp < oldest_time)) {
257 		tl->total -= tl->packet_count[tl->head];
258 		tl->packet_count[tl->head] = 0;
259 		tl->time_stamp += TID_QUEUE_CELL_SPACING;
260 		tl->queue_count--;
261 		tl->head++;
262 		if (tl->head >= TID_QUEUE_MAX_SIZE)
263 			tl->head = 0;
264 	}
265 }
266 
267 /*
268  *	increment traffic load value for tid and also remove
269  *	any old values if passed the certain time period
270  */
iwl4965_rs_tl_add_packet(struct iwl_lq_sta * lq_data,struct ieee80211_hdr * hdr)271 static u8 iwl4965_rs_tl_add_packet(struct iwl_lq_sta *lq_data,
272 			   struct ieee80211_hdr *hdr)
273 {
274 	u32 curr_time = jiffies_to_msecs(jiffies);
275 	u32 time_diff;
276 	s32 index;
277 	struct iwl_traffic_load *tl = NULL;
278 	u8 tid;
279 
280 	if (ieee80211_is_data_qos(hdr->frame_control)) {
281 		u8 *qc = ieee80211_get_qos_ctl(hdr);
282 		tid = qc[0] & 0xf;
283 	} else
284 		return MAX_TID_COUNT;
285 
286 	if (unlikely(tid >= TID_MAX_LOAD_COUNT))
287 		return MAX_TID_COUNT;
288 
289 	tl = &lq_data->load[tid];
290 
291 	curr_time -= curr_time % TID_ROUND_VALUE;
292 
293 	/* Happens only for the first packet. Initialize the data */
294 	if (!(tl->queue_count)) {
295 		tl->total = 1;
296 		tl->time_stamp = curr_time;
297 		tl->queue_count = 1;
298 		tl->head = 0;
299 		tl->packet_count[0] = 1;
300 		return MAX_TID_COUNT;
301 	}
302 
303 	time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
304 	index = time_diff / TID_QUEUE_CELL_SPACING;
305 
306 	/* The history is too long: remove data that is older than */
307 	/* TID_MAX_TIME_DIFF */
308 	if (index >= TID_QUEUE_MAX_SIZE)
309 		iwl4965_rs_tl_rm_old_stats(tl, curr_time);
310 
311 	index = (tl->head + index) % TID_QUEUE_MAX_SIZE;
312 	tl->packet_count[index] = tl->packet_count[index] + 1;
313 	tl->total = tl->total + 1;
314 
315 	if ((index + 1) > tl->queue_count)
316 		tl->queue_count = index + 1;
317 
318 	return tid;
319 }
320 
321 /*
322 	get the traffic load value for tid
323 */
iwl4965_rs_tl_get_load(struct iwl_lq_sta * lq_data,u8 tid)324 static u32 iwl4965_rs_tl_get_load(struct iwl_lq_sta *lq_data, u8 tid)
325 {
326 	u32 curr_time = jiffies_to_msecs(jiffies);
327 	u32 time_diff;
328 	s32 index;
329 	struct iwl_traffic_load *tl = NULL;
330 
331 	if (tid >= TID_MAX_LOAD_COUNT)
332 		return 0;
333 
334 	tl = &(lq_data->load[tid]);
335 
336 	curr_time -= curr_time % TID_ROUND_VALUE;
337 
338 	if (!(tl->queue_count))
339 		return 0;
340 
341 	time_diff = TIME_WRAP_AROUND(tl->time_stamp, curr_time);
342 	index = time_diff / TID_QUEUE_CELL_SPACING;
343 
344 	/* The history is too long: remove data that is older than */
345 	/* TID_MAX_TIME_DIFF */
346 	if (index >= TID_QUEUE_MAX_SIZE)
347 		iwl4965_rs_tl_rm_old_stats(tl, curr_time);
348 
349 	return tl->total;
350 }
351 
iwl4965_rs_tl_turn_on_agg_for_tid(struct iwl_priv * priv,struct iwl_lq_sta * lq_data,u8 tid,struct ieee80211_sta * sta)352 static int iwl4965_rs_tl_turn_on_agg_for_tid(struct iwl_priv *priv,
353 				      struct iwl_lq_sta *lq_data, u8 tid,
354 				      struct ieee80211_sta *sta)
355 {
356 	int ret = -EAGAIN;
357 	u32 load;
358 
359 	load = iwl4965_rs_tl_get_load(lq_data, tid);
360 
361 	if (load > IWL_AGG_LOAD_THRESHOLD) {
362 		IWL_DEBUG_HT(priv, "Starting Tx agg: STA: %pM tid: %d\n",
363 				sta->addr, tid);
364 		ret = ieee80211_start_tx_ba_session(sta, tid, 5000);
365 		if (ret == -EAGAIN) {
366 			/*
367 			 * driver and mac80211 is out of sync
368 			 * this might be cause by reloading firmware
369 			 * stop the tx ba session here
370 			 */
371 			IWL_ERR(priv, "Fail start Tx agg on tid: %d\n",
372 				tid);
373 			ieee80211_stop_tx_ba_session(sta, tid);
374 		}
375 	} else {
376 		IWL_ERR(priv, "Aggregation not enabled for tid %d "
377 			"because load = %u\n", tid, load);
378 	}
379 	return ret;
380 }
381 
iwl4965_rs_tl_turn_on_agg(struct iwl_priv * priv,u8 tid,struct iwl_lq_sta * lq_data,struct ieee80211_sta * sta)382 static void iwl4965_rs_tl_turn_on_agg(struct iwl_priv *priv, u8 tid,
383 			      struct iwl_lq_sta *lq_data,
384 			      struct ieee80211_sta *sta)
385 {
386 	if (tid < TID_MAX_LOAD_COUNT)
387 		iwl4965_rs_tl_turn_on_agg_for_tid(priv, lq_data, tid, sta);
388 	else
389 		IWL_ERR(priv, "tid exceeds max load count: %d/%d\n",
390 			tid, TID_MAX_LOAD_COUNT);
391 }
392 
iwl4965_get_iwl4965_num_of_ant_from_rate(u32 rate_n_flags)393 static inline int iwl4965_get_iwl4965_num_of_ant_from_rate(u32 rate_n_flags)
394 {
395 	return !!(rate_n_flags & RATE_MCS_ANT_A_MSK) +
396 	       !!(rate_n_flags & RATE_MCS_ANT_B_MSK) +
397 	       !!(rate_n_flags & RATE_MCS_ANT_C_MSK);
398 }
399 
400 /*
401  * Static function to get the expected throughput from an iwl_scale_tbl_info
402  * that wraps a NULL pointer check
403  */
404 static s32
iwl4965_get_expected_tpt(struct iwl_scale_tbl_info * tbl,int rs_index)405 iwl4965_get_expected_tpt(struct iwl_scale_tbl_info *tbl, int rs_index)
406 {
407 	if (tbl->expected_tpt)
408 		return tbl->expected_tpt[rs_index];
409 	return 0;
410 }
411 
412 /**
413  * iwl4965_rs_collect_tx_data - Update the success/failure sliding window
414  *
415  * We keep a sliding window of the last 62 packets transmitted
416  * at this rate.  window->data contains the bitmask of successful
417  * packets.
418  */
iwl4965_rs_collect_tx_data(struct iwl_scale_tbl_info * tbl,int scale_index,int attempts,int successes)419 static int iwl4965_rs_collect_tx_data(struct iwl_scale_tbl_info *tbl,
420 			      int scale_index, int attempts, int successes)
421 {
422 	struct iwl_rate_scale_data *window = NULL;
423 	static const u64 mask = (((u64)1) << (IWL_RATE_MAX_WINDOW - 1));
424 	s32 fail_count, tpt;
425 
426 	if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
427 		return -EINVAL;
428 
429 	/* Select window for current tx bit rate */
430 	window = &(tbl->win[scale_index]);
431 
432 	/* Get expected throughput */
433 	tpt = iwl4965_get_expected_tpt(tbl, scale_index);
434 
435 	/*
436 	 * Keep track of only the latest 62 tx frame attempts in this rate's
437 	 * history window; anything older isn't really relevant any more.
438 	 * If we have filled up the sliding window, drop the oldest attempt;
439 	 * if the oldest attempt (highest bit in bitmap) shows "success",
440 	 * subtract "1" from the success counter (this is the main reason
441 	 * we keep these bitmaps!).
442 	 */
443 	while (attempts > 0) {
444 		if (window->counter >= IWL_RATE_MAX_WINDOW) {
445 
446 			/* remove earliest */
447 			window->counter = IWL_RATE_MAX_WINDOW - 1;
448 
449 			if (window->data & mask) {
450 				window->data &= ~mask;
451 				window->success_counter--;
452 			}
453 		}
454 
455 		/* Increment frames-attempted counter */
456 		window->counter++;
457 
458 		/* Shift bitmap by one frame to throw away oldest history */
459 		window->data <<= 1;
460 
461 		/* Mark the most recent #successes attempts as successful */
462 		if (successes > 0) {
463 			window->success_counter++;
464 			window->data |= 0x1;
465 			successes--;
466 		}
467 
468 		attempts--;
469 	}
470 
471 	/* Calculate current success ratio, avoid divide-by-0! */
472 	if (window->counter > 0)
473 		window->success_ratio = 128 * (100 * window->success_counter)
474 					/ window->counter;
475 	else
476 		window->success_ratio = IWL_INVALID_VALUE;
477 
478 	fail_count = window->counter - window->success_counter;
479 
480 	/* Calculate average throughput, if we have enough history. */
481 	if ((fail_count >= IWL_RATE_MIN_FAILURE_TH) ||
482 	    (window->success_counter >= IWL_RATE_MIN_SUCCESS_TH))
483 		window->average_tpt = (window->success_ratio * tpt + 64) / 128;
484 	else
485 		window->average_tpt = IWL_INVALID_VALUE;
486 
487 	/* Tag this window as having been updated */
488 	window->stamp = jiffies;
489 
490 	return 0;
491 }
492 
493 /*
494  * Fill uCode API rate_n_flags field, based on "search" or "active" table.
495  */
iwl4965_rate_n_flags_from_tbl(struct iwl_priv * priv,struct iwl_scale_tbl_info * tbl,int index,u8 use_green)496 static u32 iwl4965_rate_n_flags_from_tbl(struct iwl_priv *priv,
497 				 struct iwl_scale_tbl_info *tbl,
498 				 int index, u8 use_green)
499 {
500 	u32 rate_n_flags = 0;
501 
502 	if (is_legacy(tbl->lq_type)) {
503 		rate_n_flags = iwlegacy_rates[index].plcp;
504 		if (index >= IWL_FIRST_CCK_RATE && index <= IWL_LAST_CCK_RATE)
505 			rate_n_flags |= RATE_MCS_CCK_MSK;
506 
507 	} else if (is_Ht(tbl->lq_type)) {
508 		if (index > IWL_LAST_OFDM_RATE) {
509 			IWL_ERR(priv, "Invalid HT rate index %d\n", index);
510 			index = IWL_LAST_OFDM_RATE;
511 		}
512 		rate_n_flags = RATE_MCS_HT_MSK;
513 
514 		if (is_siso(tbl->lq_type))
515 			rate_n_flags |=	iwlegacy_rates[index].plcp_siso;
516 		else
517 			rate_n_flags |=	iwlegacy_rates[index].plcp_mimo2;
518 	} else {
519 		IWL_ERR(priv, "Invalid tbl->lq_type %d\n", tbl->lq_type);
520 	}
521 
522 	rate_n_flags |= ((tbl->ant_type << RATE_MCS_ANT_POS) &
523 						     RATE_MCS_ANT_ABC_MSK);
524 
525 	if (is_Ht(tbl->lq_type)) {
526 		if (tbl->is_ht40) {
527 			if (tbl->is_dup)
528 				rate_n_flags |= RATE_MCS_DUP_MSK;
529 			else
530 				rate_n_flags |= RATE_MCS_HT40_MSK;
531 		}
532 		if (tbl->is_SGI)
533 			rate_n_flags |= RATE_MCS_SGI_MSK;
534 
535 		if (use_green) {
536 			rate_n_flags |= RATE_MCS_GF_MSK;
537 			if (is_siso(tbl->lq_type) && tbl->is_SGI) {
538 				rate_n_flags &= ~RATE_MCS_SGI_MSK;
539 				IWL_ERR(priv, "GF was set with SGI:SISO\n");
540 			}
541 		}
542 	}
543 	return rate_n_flags;
544 }
545 
546 /*
547  * Interpret uCode API's rate_n_flags format,
548  * fill "search" or "active" tx mode table.
549  */
iwl4965_rs_get_tbl_info_from_mcs(const u32 rate_n_flags,enum ieee80211_band band,struct iwl_scale_tbl_info * tbl,int * rate_idx)550 static int iwl4965_rs_get_tbl_info_from_mcs(const u32 rate_n_flags,
551 				    enum ieee80211_band band,
552 				    struct iwl_scale_tbl_info *tbl,
553 				    int *rate_idx)
554 {
555 	u32 ant_msk = (rate_n_flags & RATE_MCS_ANT_ABC_MSK);
556 	u8 iwl4965_num_of_ant = iwl4965_get_iwl4965_num_of_ant_from_rate(rate_n_flags);
557 	u8 mcs;
558 
559 	memset(tbl, 0, sizeof(struct iwl_scale_tbl_info));
560 	*rate_idx = iwl4965_hwrate_to_plcp_idx(rate_n_flags);
561 
562 	if (*rate_idx  == IWL_RATE_INVALID) {
563 		*rate_idx = -1;
564 		return -EINVAL;
565 	}
566 	tbl->is_SGI = 0;	/* default legacy setup */
567 	tbl->is_ht40 = 0;
568 	tbl->is_dup = 0;
569 	tbl->ant_type = (ant_msk >> RATE_MCS_ANT_POS);
570 	tbl->lq_type = LQ_NONE;
571 	tbl->max_search = IWL_MAX_SEARCH;
572 
573 	/* legacy rate format */
574 	if (!(rate_n_flags & RATE_MCS_HT_MSK)) {
575 		if (iwl4965_num_of_ant == 1) {
576 			if (band == IEEE80211_BAND_5GHZ)
577 				tbl->lq_type = LQ_A;
578 			else
579 				tbl->lq_type = LQ_G;
580 		}
581 	/* HT rate format */
582 	} else {
583 		if (rate_n_flags & RATE_MCS_SGI_MSK)
584 			tbl->is_SGI = 1;
585 
586 		if ((rate_n_flags & RATE_MCS_HT40_MSK) ||
587 		    (rate_n_flags & RATE_MCS_DUP_MSK))
588 			tbl->is_ht40 = 1;
589 
590 		if (rate_n_flags & RATE_MCS_DUP_MSK)
591 			tbl->is_dup = 1;
592 
593 		mcs = iwl4965_rs_extract_rate(rate_n_flags);
594 
595 		/* SISO */
596 		if (mcs <= IWL_RATE_SISO_60M_PLCP) {
597 			if (iwl4965_num_of_ant == 1)
598 				tbl->lq_type = LQ_SISO; /*else NONE*/
599 		/* MIMO2 */
600 		} else {
601 			if (iwl4965_num_of_ant == 2)
602 				tbl->lq_type = LQ_MIMO2;
603 		}
604 	}
605 	return 0;
606 }
607 
608 /* switch to another antenna/antennas and return 1 */
609 /* if no other valid antenna found, return 0 */
iwl4965_rs_toggle_antenna(u32 valid_ant,u32 * rate_n_flags,struct iwl_scale_tbl_info * tbl)610 static int iwl4965_rs_toggle_antenna(u32 valid_ant, u32 *rate_n_flags,
611 			     struct iwl_scale_tbl_info *tbl)
612 {
613 	u8 new_ant_type;
614 
615 	if (!tbl->ant_type || tbl->ant_type > ANT_ABC)
616 		return 0;
617 
618 	if (!iwl4965_rs_is_valid_ant(valid_ant, tbl->ant_type))
619 		return 0;
620 
621 	new_ant_type = ant_toggle_lookup[tbl->ant_type];
622 
623 	while ((new_ant_type != tbl->ant_type) &&
624 	       !iwl4965_rs_is_valid_ant(valid_ant, new_ant_type))
625 		new_ant_type = ant_toggle_lookup[new_ant_type];
626 
627 	if (new_ant_type == tbl->ant_type)
628 		return 0;
629 
630 	tbl->ant_type = new_ant_type;
631 	*rate_n_flags &= ~RATE_MCS_ANT_ABC_MSK;
632 	*rate_n_flags |= new_ant_type << RATE_MCS_ANT_POS;
633 	return 1;
634 }
635 
636 /**
637  * Green-field mode is valid if the station supports it and
638  * there are no non-GF stations present in the BSS.
639  */
iwl4965_rs_use_green(struct ieee80211_sta * sta)640 static bool iwl4965_rs_use_green(struct ieee80211_sta *sta)
641 {
642 	struct iwl_station_priv *sta_priv = (void *)sta->drv_priv;
643 	struct iwl_rxon_context *ctx = sta_priv->common.ctx;
644 
645 	return (sta->ht_cap.cap & IEEE80211_HT_CAP_GRN_FLD) &&
646 		!(ctx->ht.non_gf_sta_present);
647 }
648 
649 /**
650  * iwl4965_rs_get_supported_rates - get the available rates
651  *
652  * if management frame or broadcast frame only return
653  * basic available rates.
654  *
655  */
iwl4965_rs_get_supported_rates(struct iwl_lq_sta * lq_sta,struct ieee80211_hdr * hdr,enum iwl_table_type rate_type)656 static u16 iwl4965_rs_get_supported_rates(struct iwl_lq_sta *lq_sta,
657 				  struct ieee80211_hdr *hdr,
658 				  enum iwl_table_type rate_type)
659 {
660 	if (is_legacy(rate_type)) {
661 		return lq_sta->active_legacy_rate;
662 	} else {
663 		if (is_siso(rate_type))
664 			return lq_sta->active_siso_rate;
665 		else
666 			return lq_sta->active_mimo2_rate;
667 	}
668 }
669 
670 static u16
iwl4965_rs_get_adjacent_rate(struct iwl_priv * priv,u8 index,u16 rate_mask,int rate_type)671 iwl4965_rs_get_adjacent_rate(struct iwl_priv *priv, u8 index, u16 rate_mask,
672 				int rate_type)
673 {
674 	u8 high = IWL_RATE_INVALID;
675 	u8 low = IWL_RATE_INVALID;
676 
677 	/* 802.11A or ht walks to the next literal adjacent rate in
678 	 * the rate table */
679 	if (is_a_band(rate_type) || !is_legacy(rate_type)) {
680 		int i;
681 		u32 mask;
682 
683 		/* Find the previous rate that is in the rate mask */
684 		i = index - 1;
685 		for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
686 			if (rate_mask & mask) {
687 				low = i;
688 				break;
689 			}
690 		}
691 
692 		/* Find the next rate that is in the rate mask */
693 		i = index + 1;
694 		for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
695 			if (rate_mask & mask) {
696 				high = i;
697 				break;
698 			}
699 		}
700 
701 		return (high << 8) | low;
702 	}
703 
704 	low = index;
705 	while (low != IWL_RATE_INVALID) {
706 		low = iwlegacy_rates[low].prev_rs;
707 		if (low == IWL_RATE_INVALID)
708 			break;
709 		if (rate_mask & (1 << low))
710 			break;
711 		IWL_DEBUG_RATE(priv, "Skipping masked lower rate: %d\n", low);
712 	}
713 
714 	high = index;
715 	while (high != IWL_RATE_INVALID) {
716 		high = iwlegacy_rates[high].next_rs;
717 		if (high == IWL_RATE_INVALID)
718 			break;
719 		if (rate_mask & (1 << high))
720 			break;
721 		IWL_DEBUG_RATE(priv, "Skipping masked higher rate: %d\n", high);
722 	}
723 
724 	return (high << 8) | low;
725 }
726 
iwl4965_rs_get_lower_rate(struct iwl_lq_sta * lq_sta,struct iwl_scale_tbl_info * tbl,u8 scale_index,u8 ht_possible)727 static u32 iwl4965_rs_get_lower_rate(struct iwl_lq_sta *lq_sta,
728 			     struct iwl_scale_tbl_info *tbl,
729 			     u8 scale_index, u8 ht_possible)
730 {
731 	s32 low;
732 	u16 rate_mask;
733 	u16 high_low;
734 	u8 switch_to_legacy = 0;
735 	u8 is_green = lq_sta->is_green;
736 	struct iwl_priv *priv = lq_sta->drv;
737 
738 	/* check if we need to switch from HT to legacy rates.
739 	 * assumption is that mandatory rates (1Mbps or 6Mbps)
740 	 * are always supported (spec demand) */
741 	if (!is_legacy(tbl->lq_type) && (!ht_possible || !scale_index)) {
742 		switch_to_legacy = 1;
743 		scale_index = rs_ht_to_legacy[scale_index];
744 		if (lq_sta->band == IEEE80211_BAND_5GHZ)
745 			tbl->lq_type = LQ_A;
746 		else
747 			tbl->lq_type = LQ_G;
748 
749 		if (iwl4965_num_of_ant(tbl->ant_type) > 1)
750 			tbl->ant_type =
751 				iwl4965_first_antenna(priv->hw_params.valid_tx_ant);
752 
753 		tbl->is_ht40 = 0;
754 		tbl->is_SGI = 0;
755 		tbl->max_search = IWL_MAX_SEARCH;
756 	}
757 
758 	rate_mask = iwl4965_rs_get_supported_rates(lq_sta, NULL, tbl->lq_type);
759 
760 	/* Mask with station rate restriction */
761 	if (is_legacy(tbl->lq_type)) {
762 		/* supp_rates has no CCK bits in A mode */
763 		if (lq_sta->band == IEEE80211_BAND_5GHZ)
764 			rate_mask  = (u16)(rate_mask &
765 			   (lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
766 		else
767 			rate_mask = (u16)(rate_mask & lq_sta->supp_rates);
768 	}
769 
770 	/* If we switched from HT to legacy, check current rate */
771 	if (switch_to_legacy && (rate_mask & (1 << scale_index))) {
772 		low = scale_index;
773 		goto out;
774 	}
775 
776 	high_low = iwl4965_rs_get_adjacent_rate(lq_sta->drv,
777 					scale_index, rate_mask,
778 					tbl->lq_type);
779 	low = high_low & 0xff;
780 
781 	if (low == IWL_RATE_INVALID)
782 		low = scale_index;
783 
784 out:
785 	return iwl4965_rate_n_flags_from_tbl(lq_sta->drv, tbl, low, is_green);
786 }
787 
788 /*
789  * Simple function to compare two rate scale table types
790  */
iwl4965_table_type_matches(struct iwl_scale_tbl_info * a,struct iwl_scale_tbl_info * b)791 static bool iwl4965_table_type_matches(struct iwl_scale_tbl_info *a,
792 			       struct iwl_scale_tbl_info *b)
793 {
794 	return (a->lq_type == b->lq_type) && (a->ant_type == b->ant_type) &&
795 		(a->is_SGI == b->is_SGI);
796 }
797 
798 /*
799  * mac80211 sends us Tx status
800  */
801 static void
iwl4965_rs_tx_status(void * priv_r,struct ieee80211_supported_band * sband,struct ieee80211_sta * sta,void * priv_sta,struct sk_buff * skb)802 iwl4965_rs_tx_status(void *priv_r, struct ieee80211_supported_band *sband,
803 			 struct ieee80211_sta *sta, void *priv_sta,
804 			 struct sk_buff *skb)
805 {
806 	int legacy_success;
807 	int retries;
808 	int rs_index, mac_index, i;
809 	struct iwl_lq_sta *lq_sta = priv_sta;
810 	struct iwl_link_quality_cmd *table;
811 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
812 	struct iwl_priv *priv = (struct iwl_priv *)priv_r;
813 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
814 	enum mac80211_rate_control_flags mac_flags;
815 	u32 tx_rate;
816 	struct iwl_scale_tbl_info tbl_type;
817 	struct iwl_scale_tbl_info *curr_tbl, *other_tbl, *tmp_tbl;
818 	struct iwl_station_priv *sta_priv = (void *)sta->drv_priv;
819 	struct iwl_rxon_context *ctx = sta_priv->common.ctx;
820 
821 	IWL_DEBUG_RATE_LIMIT(priv,
822 		"get frame ack response, update rate scale window\n");
823 
824 	/* Treat uninitialized rate scaling data same as non-existing. */
825 	if (!lq_sta) {
826 		IWL_DEBUG_RATE(priv, "Station rate scaling not created yet.\n");
827 		return;
828 	} else if (!lq_sta->drv) {
829 		IWL_DEBUG_RATE(priv, "Rate scaling not initialized yet.\n");
830 		return;
831 	}
832 
833 	if (!ieee80211_is_data(hdr->frame_control) ||
834 	    info->flags & IEEE80211_TX_CTL_NO_ACK)
835 		return;
836 
837 	/* This packet was aggregated but doesn't carry status info */
838 	if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
839 	    !(info->flags & IEEE80211_TX_STAT_AMPDU))
840 		return;
841 
842 	/*
843 	 * Ignore this Tx frame response if its initial rate doesn't match
844 	 * that of latest Link Quality command.  There may be stragglers
845 	 * from a previous Link Quality command, but we're no longer interested
846 	 * in those; they're either from the "active" mode while we're trying
847 	 * to check "search" mode, or a prior "search" mode after we've moved
848 	 * to a new "search" mode (which might become the new "active" mode).
849 	 */
850 	table = &lq_sta->lq;
851 	tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
852 	iwl4965_rs_get_tbl_info_from_mcs(tx_rate,
853 			 priv->band, &tbl_type, &rs_index);
854 	if (priv->band == IEEE80211_BAND_5GHZ)
855 		rs_index -= IWL_FIRST_OFDM_RATE;
856 	mac_flags = info->status.rates[0].flags;
857 	mac_index = info->status.rates[0].idx;
858 	/* For HT packets, map MCS to PLCP */
859 	if (mac_flags & IEEE80211_TX_RC_MCS) {
860 		mac_index &= RATE_MCS_CODE_MSK;	/* Remove # of streams */
861 		if (mac_index >= (IWL_RATE_9M_INDEX - IWL_FIRST_OFDM_RATE))
862 			mac_index++;
863 		/*
864 		 * mac80211 HT index is always zero-indexed; we need to move
865 		 * HT OFDM rates after CCK rates in 2.4 GHz band
866 		 */
867 		if (priv->band == IEEE80211_BAND_2GHZ)
868 			mac_index += IWL_FIRST_OFDM_RATE;
869 	}
870 	/* Here we actually compare this rate to the latest LQ command */
871 	if ((mac_index < 0) ||
872 	    (tbl_type.is_SGI !=
873 			!!(mac_flags & IEEE80211_TX_RC_SHORT_GI)) ||
874 	    (tbl_type.is_ht40 !=
875 			!!(mac_flags & IEEE80211_TX_RC_40_MHZ_WIDTH)) ||
876 	    (tbl_type.is_dup !=
877 			!!(mac_flags & IEEE80211_TX_RC_DUP_DATA)) ||
878 	    (tbl_type.ant_type != info->antenna_sel_tx) ||
879 	    (!!(tx_rate & RATE_MCS_HT_MSK) !=
880 			!!(mac_flags & IEEE80211_TX_RC_MCS)) ||
881 	    (!!(tx_rate & RATE_MCS_GF_MSK) !=
882 			!!(mac_flags & IEEE80211_TX_RC_GREEN_FIELD)) ||
883 	    (rs_index != mac_index)) {
884 		IWL_DEBUG_RATE(priv,
885 		"initial rate %d does not match %d (0x%x)\n",
886 			 mac_index, rs_index, tx_rate);
887 		/*
888 		 * Since rates mis-match, the last LQ command may have failed.
889 		 * After IWL_MISSED_RATE_MAX mis-matches, resync the uCode with
890 		 * ... driver.
891 		 */
892 		lq_sta->missed_rate_counter++;
893 		if (lq_sta->missed_rate_counter > IWL_MISSED_RATE_MAX) {
894 			lq_sta->missed_rate_counter = 0;
895 			iwl_legacy_send_lq_cmd(priv, ctx, &lq_sta->lq,
896 							CMD_ASYNC, false);
897 		}
898 		/* Regardless, ignore this status info for outdated rate */
899 		return;
900 	} else
901 		/* Rate did match, so reset the missed_rate_counter */
902 		lq_sta->missed_rate_counter = 0;
903 
904 	/* Figure out if rate scale algorithm is in active or search table */
905 	if (iwl4965_table_type_matches(&tbl_type,
906 				&(lq_sta->lq_info[lq_sta->active_tbl]))) {
907 		curr_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
908 		other_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
909 	} else if (iwl4965_table_type_matches(&tbl_type,
910 				&lq_sta->lq_info[1 - lq_sta->active_tbl])) {
911 		curr_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
912 		other_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
913 	} else {
914 		IWL_DEBUG_RATE(priv,
915 			"Neither active nor search matches tx rate\n");
916 		tmp_tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
917 		IWL_DEBUG_RATE(priv, "active- lq:%x, ant:%x, SGI:%d\n",
918 			tmp_tbl->lq_type, tmp_tbl->ant_type, tmp_tbl->is_SGI);
919 		tmp_tbl = &(lq_sta->lq_info[1 - lq_sta->active_tbl]);
920 		IWL_DEBUG_RATE(priv, "search- lq:%x, ant:%x, SGI:%d\n",
921 			tmp_tbl->lq_type, tmp_tbl->ant_type, tmp_tbl->is_SGI);
922 		IWL_DEBUG_RATE(priv, "actual- lq:%x, ant:%x, SGI:%d\n",
923 			tbl_type.lq_type, tbl_type.ant_type, tbl_type.is_SGI);
924 		/*
925 		 * no matching table found, let's by-pass the data collection
926 		 * and continue to perform rate scale to find the rate table
927 		 */
928 		iwl4965_rs_stay_in_table(lq_sta, true);
929 		goto done;
930 	}
931 
932 	/*
933 	 * Updating the frame history depends on whether packets were
934 	 * aggregated.
935 	 *
936 	 * For aggregation, all packets were transmitted at the same rate, the
937 	 * first index into rate scale table.
938 	 */
939 	if (info->flags & IEEE80211_TX_STAT_AMPDU) {
940 		tx_rate = le32_to_cpu(table->rs_table[0].rate_n_flags);
941 		iwl4965_rs_get_tbl_info_from_mcs(tx_rate, priv->band, &tbl_type,
942 				&rs_index);
943 		iwl4965_rs_collect_tx_data(curr_tbl, rs_index,
944 				   info->status.ampdu_len,
945 				   info->status.ampdu_ack_len);
946 
947 		/* Update success/fail counts if not searching for new mode */
948 		if (lq_sta->stay_in_tbl) {
949 			lq_sta->total_success += info->status.ampdu_ack_len;
950 			lq_sta->total_failed += (info->status.ampdu_len -
951 					info->status.ampdu_ack_len);
952 		}
953 	} else {
954 	/*
955 	 * For legacy, update frame history with for each Tx retry.
956 	 */
957 		retries = info->status.rates[0].count - 1;
958 		/* HW doesn't send more than 15 retries */
959 		retries = min(retries, 15);
960 
961 		/* The last transmission may have been successful */
962 		legacy_success = !!(info->flags & IEEE80211_TX_STAT_ACK);
963 		/* Collect data for each rate used during failed TX attempts */
964 		for (i = 0; i <= retries; ++i) {
965 			tx_rate = le32_to_cpu(table->rs_table[i].rate_n_flags);
966 			iwl4965_rs_get_tbl_info_from_mcs(tx_rate, priv->band,
967 					&tbl_type, &rs_index);
968 			/*
969 			 * Only collect stats if retried rate is in the same RS
970 			 * table as active/search.
971 			 */
972 			if (iwl4965_table_type_matches(&tbl_type, curr_tbl))
973 				tmp_tbl = curr_tbl;
974 			else if (iwl4965_table_type_matches(&tbl_type,
975 								 other_tbl))
976 				tmp_tbl = other_tbl;
977 			else
978 				continue;
979 			iwl4965_rs_collect_tx_data(tmp_tbl, rs_index, 1,
980 					   i < retries ? 0 : legacy_success);
981 		}
982 
983 		/* Update success/fail counts if not searching for new mode */
984 		if (lq_sta->stay_in_tbl) {
985 			lq_sta->total_success += legacy_success;
986 			lq_sta->total_failed += retries + (1 - legacy_success);
987 		}
988 	}
989 	/* The last TX rate is cached in lq_sta; it's set in if/else above */
990 	lq_sta->last_rate_n_flags = tx_rate;
991 done:
992 	/* See if there's a better rate or modulation mode to try. */
993 	if (sta && sta->supp_rates[sband->band])
994 		iwl4965_rs_rate_scale_perform(priv, skb, sta, lq_sta);
995 }
996 
997 /*
998  * Begin a period of staying with a selected modulation mode.
999  * Set "stay_in_tbl" flag to prevent any mode switches.
1000  * Set frame tx success limits according to legacy vs. high-throughput,
1001  * and reset overall (spanning all rates) tx success history statistics.
1002  * These control how long we stay using same modulation mode before
1003  * searching for a new mode.
1004  */
iwl4965_rs_set_stay_in_table(struct iwl_priv * priv,u8 is_legacy,struct iwl_lq_sta * lq_sta)1005 static void iwl4965_rs_set_stay_in_table(struct iwl_priv *priv, u8 is_legacy,
1006 				 struct iwl_lq_sta *lq_sta)
1007 {
1008 	IWL_DEBUG_RATE(priv, "we are staying in the same table\n");
1009 	lq_sta->stay_in_tbl = 1;	/* only place this gets set */
1010 	if (is_legacy) {
1011 		lq_sta->table_count_limit = IWL_LEGACY_TABLE_COUNT;
1012 		lq_sta->max_failure_limit = IWL_LEGACY_FAILURE_LIMIT;
1013 		lq_sta->max_success_limit = IWL_LEGACY_SUCCESS_LIMIT;
1014 	} else {
1015 		lq_sta->table_count_limit = IWL_NONE_LEGACY_TABLE_COUNT;
1016 		lq_sta->max_failure_limit = IWL_NONE_LEGACY_FAILURE_LIMIT;
1017 		lq_sta->max_success_limit = IWL_NONE_LEGACY_SUCCESS_LIMIT;
1018 	}
1019 	lq_sta->table_count = 0;
1020 	lq_sta->total_failed = 0;
1021 	lq_sta->total_success = 0;
1022 	lq_sta->flush_timer = jiffies;
1023 	lq_sta->action_counter = 0;
1024 }
1025 
1026 /*
1027  * Find correct throughput table for given mode of modulation
1028  */
iwl4965_rs_set_expected_tpt_table(struct iwl_lq_sta * lq_sta,struct iwl_scale_tbl_info * tbl)1029 static void iwl4965_rs_set_expected_tpt_table(struct iwl_lq_sta *lq_sta,
1030 				      struct iwl_scale_tbl_info *tbl)
1031 {
1032 	/* Used to choose among HT tables */
1033 	s32 (*ht_tbl_pointer)[IWL_RATE_COUNT];
1034 
1035 	/* Check for invalid LQ type */
1036 	if (WARN_ON_ONCE(!is_legacy(tbl->lq_type) && !is_Ht(tbl->lq_type))) {
1037 		tbl->expected_tpt = expected_tpt_legacy;
1038 		return;
1039 	}
1040 
1041 	/* Legacy rates have only one table */
1042 	if (is_legacy(tbl->lq_type)) {
1043 		tbl->expected_tpt = expected_tpt_legacy;
1044 		return;
1045 	}
1046 
1047 	/* Choose among many HT tables depending on number of streams
1048 	 * (SISO/MIMO2), channel width (20/40), SGI, and aggregation
1049 	 * status */
1050 	if (is_siso(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
1051 		ht_tbl_pointer = expected_tpt_siso20MHz;
1052 	else if (is_siso(tbl->lq_type))
1053 		ht_tbl_pointer = expected_tpt_siso40MHz;
1054 	else if (is_mimo2(tbl->lq_type) && (!tbl->is_ht40 || lq_sta->is_dup))
1055 		ht_tbl_pointer = expected_tpt_mimo2_20MHz;
1056 	else /* if (is_mimo2(tbl->lq_type)) <-- must be true */
1057 		ht_tbl_pointer = expected_tpt_mimo2_40MHz;
1058 
1059 	if (!tbl->is_SGI && !lq_sta->is_agg)		/* Normal */
1060 		tbl->expected_tpt = ht_tbl_pointer[0];
1061 	else if (tbl->is_SGI && !lq_sta->is_agg)	/* SGI */
1062 		tbl->expected_tpt = ht_tbl_pointer[1];
1063 	else if (!tbl->is_SGI && lq_sta->is_agg)	/* AGG */
1064 		tbl->expected_tpt = ht_tbl_pointer[2];
1065 	else						/* AGG+SGI */
1066 		tbl->expected_tpt = ht_tbl_pointer[3];
1067 }
1068 
1069 /*
1070  * Find starting rate for new "search" high-throughput mode of modulation.
1071  * Goal is to find lowest expected rate (under perfect conditions) that is
1072  * above the current measured throughput of "active" mode, to give new mode
1073  * a fair chance to prove itself without too many challenges.
1074  *
1075  * This gets called when transitioning to more aggressive modulation
1076  * (i.e. legacy to SISO or MIMO, or SISO to MIMO), as well as less aggressive
1077  * (i.e. MIMO to SISO).  When moving to MIMO, bit rate will typically need
1078  * to decrease to match "active" throughput.  When moving from MIMO to SISO,
1079  * bit rate will typically need to increase, but not if performance was bad.
1080  */
iwl4965_rs_get_best_rate(struct iwl_priv * priv,struct iwl_lq_sta * lq_sta,struct iwl_scale_tbl_info * tbl,u16 rate_mask,s8 index)1081 static s32 iwl4965_rs_get_best_rate(struct iwl_priv *priv,
1082 			    struct iwl_lq_sta *lq_sta,
1083 			    struct iwl_scale_tbl_info *tbl,	/* "search" */
1084 			    u16 rate_mask, s8 index)
1085 {
1086 	/* "active" values */
1087 	struct iwl_scale_tbl_info *active_tbl =
1088 	    &(lq_sta->lq_info[lq_sta->active_tbl]);
1089 	s32 active_sr = active_tbl->win[index].success_ratio;
1090 	s32 active_tpt = active_tbl->expected_tpt[index];
1091 
1092 	/* expected "search" throughput */
1093 	s32 *tpt_tbl = tbl->expected_tpt;
1094 
1095 	s32 new_rate, high, low, start_hi;
1096 	u16 high_low;
1097 	s8 rate = index;
1098 
1099 	new_rate = high = low = start_hi = IWL_RATE_INVALID;
1100 
1101 	for (; ;) {
1102 		high_low = iwl4965_rs_get_adjacent_rate(priv, rate, rate_mask,
1103 						tbl->lq_type);
1104 
1105 		low = high_low & 0xff;
1106 		high = (high_low >> 8) & 0xff;
1107 
1108 		/*
1109 		 * Lower the "search" bit rate, to give new "search" mode
1110 		 * approximately the same throughput as "active" if:
1111 		 *
1112 		 * 1) "Active" mode has been working modestly well (but not
1113 		 *    great), and expected "search" throughput (under perfect
1114 		 *    conditions) at candidate rate is above the actual
1115 		 *    measured "active" throughput (but less than expected
1116 		 *    "active" throughput under perfect conditions).
1117 		 * OR
1118 		 * 2) "Active" mode has been working perfectly or very well
1119 		 *    and expected "search" throughput (under perfect
1120 		 *    conditions) at candidate rate is above expected
1121 		 *    "active" throughput (under perfect conditions).
1122 		 */
1123 		if ((((100 * tpt_tbl[rate]) > lq_sta->last_tpt) &&
1124 		     ((active_sr > IWL_RATE_DECREASE_TH) &&
1125 		      (active_sr <= IWL_RATE_HIGH_TH) &&
1126 		      (tpt_tbl[rate] <= active_tpt))) ||
1127 		    ((active_sr >= IWL_RATE_SCALE_SWITCH) &&
1128 		     (tpt_tbl[rate] > active_tpt))) {
1129 
1130 			/* (2nd or later pass)
1131 			 * If we've already tried to raise the rate, and are
1132 			 * now trying to lower it, use the higher rate. */
1133 			if (start_hi != IWL_RATE_INVALID) {
1134 				new_rate = start_hi;
1135 				break;
1136 			}
1137 
1138 			new_rate = rate;
1139 
1140 			/* Loop again with lower rate */
1141 			if (low != IWL_RATE_INVALID)
1142 				rate = low;
1143 
1144 			/* Lower rate not available, use the original */
1145 			else
1146 				break;
1147 
1148 		/* Else try to raise the "search" rate to match "active" */
1149 		} else {
1150 			/* (2nd or later pass)
1151 			 * If we've already tried to lower the rate, and are
1152 			 * now trying to raise it, use the lower rate. */
1153 			if (new_rate != IWL_RATE_INVALID)
1154 				break;
1155 
1156 			/* Loop again with higher rate */
1157 			else if (high != IWL_RATE_INVALID) {
1158 				start_hi = high;
1159 				rate = high;
1160 
1161 			/* Higher rate not available, use the original */
1162 			} else {
1163 				new_rate = rate;
1164 				break;
1165 			}
1166 		}
1167 	}
1168 
1169 	return new_rate;
1170 }
1171 
1172 /*
1173  * Set up search table for MIMO2
1174  */
iwl4965_rs_switch_to_mimo2(struct iwl_priv * priv,struct iwl_lq_sta * lq_sta,struct ieee80211_conf * conf,struct ieee80211_sta * sta,struct iwl_scale_tbl_info * tbl,int index)1175 static int iwl4965_rs_switch_to_mimo2(struct iwl_priv *priv,
1176 			     struct iwl_lq_sta *lq_sta,
1177 			     struct ieee80211_conf *conf,
1178 			     struct ieee80211_sta *sta,
1179 			     struct iwl_scale_tbl_info *tbl, int index)
1180 {
1181 	u16 rate_mask;
1182 	s32 rate;
1183 	s8 is_green = lq_sta->is_green;
1184 	struct iwl_station_priv *sta_priv = (void *)sta->drv_priv;
1185 	struct iwl_rxon_context *ctx = sta_priv->common.ctx;
1186 
1187 	if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1188 		return -1;
1189 
1190 	if (((sta->ht_cap.cap & IEEE80211_HT_CAP_SM_PS) >> 2)
1191 						== WLAN_HT_CAP_SM_PS_STATIC)
1192 		return -1;
1193 
1194 	/* Need both Tx chains/antennas to support MIMO */
1195 	if (priv->hw_params.tx_chains_num < 2)
1196 		return -1;
1197 
1198 	IWL_DEBUG_RATE(priv, "LQ: try to switch to MIMO2\n");
1199 
1200 	tbl->lq_type = LQ_MIMO2;
1201 	tbl->is_dup = lq_sta->is_dup;
1202 	tbl->action = 0;
1203 	tbl->max_search = IWL_MAX_SEARCH;
1204 	rate_mask = lq_sta->active_mimo2_rate;
1205 
1206 	if (iwl_legacy_is_ht40_tx_allowed(priv, ctx, &sta->ht_cap))
1207 		tbl->is_ht40 = 1;
1208 	else
1209 		tbl->is_ht40 = 0;
1210 
1211 	iwl4965_rs_set_expected_tpt_table(lq_sta, tbl);
1212 
1213 	rate = iwl4965_rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1214 
1215 	IWL_DEBUG_RATE(priv, "LQ: MIMO2 best rate %d mask %X\n",
1216 				rate, rate_mask);
1217 	if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1218 		IWL_DEBUG_RATE(priv,
1219 				"Can't switch with index %d rate mask %x\n",
1220 						rate, rate_mask);
1221 		return -1;
1222 	}
1223 	tbl->current_rate = iwl4965_rate_n_flags_from_tbl(priv,
1224 						 tbl, rate, is_green);
1225 
1226 	IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1227 		     tbl->current_rate, is_green);
1228 	return 0;
1229 }
1230 
1231 /*
1232  * Set up search table for SISO
1233  */
iwl4965_rs_switch_to_siso(struct iwl_priv * priv,struct iwl_lq_sta * lq_sta,struct ieee80211_conf * conf,struct ieee80211_sta * sta,struct iwl_scale_tbl_info * tbl,int index)1234 static int iwl4965_rs_switch_to_siso(struct iwl_priv *priv,
1235 			     struct iwl_lq_sta *lq_sta,
1236 			     struct ieee80211_conf *conf,
1237 			     struct ieee80211_sta *sta,
1238 			     struct iwl_scale_tbl_info *tbl, int index)
1239 {
1240 	u16 rate_mask;
1241 	u8 is_green = lq_sta->is_green;
1242 	s32 rate;
1243 	struct iwl_station_priv *sta_priv = (void *)sta->drv_priv;
1244 	struct iwl_rxon_context *ctx = sta_priv->common.ctx;
1245 
1246 	if (!conf_is_ht(conf) || !sta->ht_cap.ht_supported)
1247 		return -1;
1248 
1249 	IWL_DEBUG_RATE(priv, "LQ: try to switch to SISO\n");
1250 
1251 	tbl->is_dup = lq_sta->is_dup;
1252 	tbl->lq_type = LQ_SISO;
1253 	tbl->action = 0;
1254 	tbl->max_search = IWL_MAX_SEARCH;
1255 	rate_mask = lq_sta->active_siso_rate;
1256 
1257 	if (iwl_legacy_is_ht40_tx_allowed(priv, ctx, &sta->ht_cap))
1258 		tbl->is_ht40 = 1;
1259 	else
1260 		tbl->is_ht40 = 0;
1261 
1262 	if (is_green)
1263 		tbl->is_SGI = 0; /*11n spec: no SGI in SISO+Greenfield*/
1264 
1265 	iwl4965_rs_set_expected_tpt_table(lq_sta, tbl);
1266 	rate = iwl4965_rs_get_best_rate(priv, lq_sta, tbl, rate_mask, index);
1267 
1268 	IWL_DEBUG_RATE(priv, "LQ: get best rate %d mask %X\n", rate, rate_mask);
1269 	if ((rate == IWL_RATE_INVALID) || !((1 << rate) & rate_mask)) {
1270 		IWL_DEBUG_RATE(priv,
1271 			"can not switch with index %d rate mask %x\n",
1272 			     rate, rate_mask);
1273 		return -1;
1274 	}
1275 	tbl->current_rate = iwl4965_rate_n_flags_from_tbl(priv,
1276 						tbl, rate, is_green);
1277 	IWL_DEBUG_RATE(priv, "LQ: Switch to new mcs %X index is green %X\n",
1278 		     tbl->current_rate, is_green);
1279 	return 0;
1280 }
1281 
1282 /*
1283  * Try to switch to new modulation mode from legacy
1284  */
iwl4965_rs_move_legacy_other(struct iwl_priv * priv,struct iwl_lq_sta * lq_sta,struct ieee80211_conf * conf,struct ieee80211_sta * sta,int index)1285 static int iwl4965_rs_move_legacy_other(struct iwl_priv *priv,
1286 				struct iwl_lq_sta *lq_sta,
1287 				struct ieee80211_conf *conf,
1288 				struct ieee80211_sta *sta,
1289 				int index)
1290 {
1291 	struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1292 	struct iwl_scale_tbl_info *search_tbl =
1293 				&(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1294 	struct iwl_rate_scale_data *window = &(tbl->win[index]);
1295 	u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1296 		  (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1297 	u8 start_action;
1298 	u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1299 	u8 tx_chains_num = priv->hw_params.tx_chains_num;
1300 	int ret = 0;
1301 	u8 update_search_tbl_counter = 0;
1302 
1303 	tbl->action = IWL_LEGACY_SWITCH_SISO;
1304 
1305 	start_action = tbl->action;
1306 	for (; ;) {
1307 		lq_sta->action_counter++;
1308 		switch (tbl->action) {
1309 		case IWL_LEGACY_SWITCH_ANTENNA1:
1310 		case IWL_LEGACY_SWITCH_ANTENNA2:
1311 			IWL_DEBUG_RATE(priv, "LQ: Legacy toggle Antenna\n");
1312 
1313 			if ((tbl->action == IWL_LEGACY_SWITCH_ANTENNA1 &&
1314 							tx_chains_num <= 1) ||
1315 			    (tbl->action == IWL_LEGACY_SWITCH_ANTENNA2 &&
1316 							tx_chains_num <= 2))
1317 				break;
1318 
1319 			/* Don't change antenna if success has been great */
1320 			if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1321 				break;
1322 
1323 			/* Set up search table to try other antenna */
1324 			memcpy(search_tbl, tbl, sz);
1325 
1326 			if (iwl4965_rs_toggle_antenna(valid_tx_ant,
1327 				&search_tbl->current_rate, search_tbl)) {
1328 				update_search_tbl_counter = 1;
1329 				iwl4965_rs_set_expected_tpt_table(lq_sta,
1330 								search_tbl);
1331 				goto out;
1332 			}
1333 			break;
1334 		case IWL_LEGACY_SWITCH_SISO:
1335 			IWL_DEBUG_RATE(priv, "LQ: Legacy switch to SISO\n");
1336 
1337 			/* Set up search table to try SISO */
1338 			memcpy(search_tbl, tbl, sz);
1339 			search_tbl->is_SGI = 0;
1340 			ret = iwl4965_rs_switch_to_siso(priv, lq_sta, conf, sta,
1341 						 search_tbl, index);
1342 			if (!ret) {
1343 				lq_sta->action_counter = 0;
1344 				goto out;
1345 			}
1346 
1347 			break;
1348 		case IWL_LEGACY_SWITCH_MIMO2_AB:
1349 		case IWL_LEGACY_SWITCH_MIMO2_AC:
1350 		case IWL_LEGACY_SWITCH_MIMO2_BC:
1351 			IWL_DEBUG_RATE(priv, "LQ: Legacy switch to MIMO2\n");
1352 
1353 			/* Set up search table to try MIMO */
1354 			memcpy(search_tbl, tbl, sz);
1355 			search_tbl->is_SGI = 0;
1356 
1357 			if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AB)
1358 				search_tbl->ant_type = ANT_AB;
1359 			else if (tbl->action == IWL_LEGACY_SWITCH_MIMO2_AC)
1360 				search_tbl->ant_type = ANT_AC;
1361 			else
1362 				search_tbl->ant_type = ANT_BC;
1363 
1364 			if (!iwl4965_rs_is_valid_ant(valid_tx_ant,
1365 						search_tbl->ant_type))
1366 				break;
1367 
1368 			ret = iwl4965_rs_switch_to_mimo2(priv, lq_sta,
1369 						conf, sta,
1370 						 search_tbl, index);
1371 			if (!ret) {
1372 				lq_sta->action_counter = 0;
1373 				goto out;
1374 			}
1375 			break;
1376 		}
1377 		tbl->action++;
1378 		if (tbl->action > IWL_LEGACY_SWITCH_MIMO2_BC)
1379 			tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1380 
1381 		if (tbl->action == start_action)
1382 			break;
1383 
1384 	}
1385 	search_tbl->lq_type = LQ_NONE;
1386 	return 0;
1387 
1388 out:
1389 	lq_sta->search_better_tbl = 1;
1390 	tbl->action++;
1391 	if (tbl->action > IWL_LEGACY_SWITCH_MIMO2_BC)
1392 		tbl->action = IWL_LEGACY_SWITCH_ANTENNA1;
1393 	if (update_search_tbl_counter)
1394 		search_tbl->action = tbl->action;
1395 	return 0;
1396 
1397 }
1398 
1399 /*
1400  * Try to switch to new modulation mode from SISO
1401  */
iwl4965_rs_move_siso_to_other(struct iwl_priv * priv,struct iwl_lq_sta * lq_sta,struct ieee80211_conf * conf,struct ieee80211_sta * sta,int index)1402 static int iwl4965_rs_move_siso_to_other(struct iwl_priv *priv,
1403 				 struct iwl_lq_sta *lq_sta,
1404 				 struct ieee80211_conf *conf,
1405 				 struct ieee80211_sta *sta, int index)
1406 {
1407 	u8 is_green = lq_sta->is_green;
1408 	struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1409 	struct iwl_scale_tbl_info *search_tbl =
1410 				&(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1411 	struct iwl_rate_scale_data *window = &(tbl->win[index]);
1412 	struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1413 	u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1414 		  (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1415 	u8 start_action;
1416 	u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1417 	u8 tx_chains_num = priv->hw_params.tx_chains_num;
1418 	u8 update_search_tbl_counter = 0;
1419 	int ret;
1420 
1421 	start_action = tbl->action;
1422 
1423 	for (;;) {
1424 		lq_sta->action_counter++;
1425 		switch (tbl->action) {
1426 		case IWL_SISO_SWITCH_ANTENNA1:
1427 		case IWL_SISO_SWITCH_ANTENNA2:
1428 			IWL_DEBUG_RATE(priv, "LQ: SISO toggle Antenna\n");
1429 			if ((tbl->action == IWL_SISO_SWITCH_ANTENNA1 &&
1430 						tx_chains_num <= 1) ||
1431 			    (tbl->action == IWL_SISO_SWITCH_ANTENNA2 &&
1432 						tx_chains_num <= 2))
1433 				break;
1434 
1435 			if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1436 				break;
1437 
1438 			memcpy(search_tbl, tbl, sz);
1439 			if (iwl4965_rs_toggle_antenna(valid_tx_ant,
1440 				       &search_tbl->current_rate, search_tbl)) {
1441 				update_search_tbl_counter = 1;
1442 				goto out;
1443 			}
1444 			break;
1445 		case IWL_SISO_SWITCH_MIMO2_AB:
1446 		case IWL_SISO_SWITCH_MIMO2_AC:
1447 		case IWL_SISO_SWITCH_MIMO2_BC:
1448 			IWL_DEBUG_RATE(priv, "LQ: SISO switch to MIMO2\n");
1449 			memcpy(search_tbl, tbl, sz);
1450 			search_tbl->is_SGI = 0;
1451 
1452 			if (tbl->action == IWL_SISO_SWITCH_MIMO2_AB)
1453 				search_tbl->ant_type = ANT_AB;
1454 			else if (tbl->action == IWL_SISO_SWITCH_MIMO2_AC)
1455 				search_tbl->ant_type = ANT_AC;
1456 			else
1457 				search_tbl->ant_type = ANT_BC;
1458 
1459 			if (!iwl4965_rs_is_valid_ant(valid_tx_ant,
1460 						 search_tbl->ant_type))
1461 				break;
1462 
1463 			ret = iwl4965_rs_switch_to_mimo2(priv, lq_sta,
1464 						conf, sta,
1465 						 search_tbl, index);
1466 			if (!ret)
1467 				goto out;
1468 			break;
1469 		case IWL_SISO_SWITCH_GI:
1470 			if (!tbl->is_ht40 && !(ht_cap->cap &
1471 						IEEE80211_HT_CAP_SGI_20))
1472 				break;
1473 			if (tbl->is_ht40 && !(ht_cap->cap &
1474 						IEEE80211_HT_CAP_SGI_40))
1475 				break;
1476 
1477 			IWL_DEBUG_RATE(priv, "LQ: SISO toggle SGI/NGI\n");
1478 
1479 			memcpy(search_tbl, tbl, sz);
1480 			if (is_green) {
1481 				if (!tbl->is_SGI)
1482 					break;
1483 				else
1484 					IWL_ERR(priv,
1485 						"SGI was set in GF+SISO\n");
1486 			}
1487 			search_tbl->is_SGI = !tbl->is_SGI;
1488 			iwl4965_rs_set_expected_tpt_table(lq_sta, search_tbl);
1489 			if (tbl->is_SGI) {
1490 				s32 tpt = lq_sta->last_tpt / 100;
1491 				if (tpt >= search_tbl->expected_tpt[index])
1492 					break;
1493 			}
1494 			search_tbl->current_rate =
1495 				iwl4965_rate_n_flags_from_tbl(priv, search_tbl,
1496 						      index, is_green);
1497 			update_search_tbl_counter = 1;
1498 			goto out;
1499 		}
1500 		tbl->action++;
1501 		if (tbl->action > IWL_SISO_SWITCH_GI)
1502 			tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1503 
1504 		if (tbl->action == start_action)
1505 			break;
1506 	}
1507 	search_tbl->lq_type = LQ_NONE;
1508 	return 0;
1509 
1510  out:
1511 	lq_sta->search_better_tbl = 1;
1512 	tbl->action++;
1513 	if (tbl->action > IWL_SISO_SWITCH_GI)
1514 		tbl->action = IWL_SISO_SWITCH_ANTENNA1;
1515 	if (update_search_tbl_counter)
1516 		search_tbl->action = tbl->action;
1517 
1518 	return 0;
1519 }
1520 
1521 /*
1522  * Try to switch to new modulation mode from MIMO2
1523  */
iwl4965_rs_move_mimo2_to_other(struct iwl_priv * priv,struct iwl_lq_sta * lq_sta,struct ieee80211_conf * conf,struct ieee80211_sta * sta,int index)1524 static int iwl4965_rs_move_mimo2_to_other(struct iwl_priv *priv,
1525 				 struct iwl_lq_sta *lq_sta,
1526 				 struct ieee80211_conf *conf,
1527 				 struct ieee80211_sta *sta, int index)
1528 {
1529 	s8 is_green = lq_sta->is_green;
1530 	struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1531 	struct iwl_scale_tbl_info *search_tbl =
1532 				&(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
1533 	struct iwl_rate_scale_data *window = &(tbl->win[index]);
1534 	struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
1535 	u32 sz = (sizeof(struct iwl_scale_tbl_info) -
1536 		  (sizeof(struct iwl_rate_scale_data) * IWL_RATE_COUNT));
1537 	u8 start_action;
1538 	u8 valid_tx_ant = priv->hw_params.valid_tx_ant;
1539 	u8 tx_chains_num = priv->hw_params.tx_chains_num;
1540 	u8 update_search_tbl_counter = 0;
1541 	int ret;
1542 
1543 	start_action = tbl->action;
1544 	for (;;) {
1545 		lq_sta->action_counter++;
1546 		switch (tbl->action) {
1547 		case IWL_MIMO2_SWITCH_ANTENNA1:
1548 		case IWL_MIMO2_SWITCH_ANTENNA2:
1549 			IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle Antennas\n");
1550 
1551 			if (tx_chains_num <= 2)
1552 				break;
1553 
1554 			if (window->success_ratio >= IWL_RS_GOOD_RATIO)
1555 				break;
1556 
1557 			memcpy(search_tbl, tbl, sz);
1558 			if (iwl4965_rs_toggle_antenna(valid_tx_ant,
1559 				       &search_tbl->current_rate, search_tbl)) {
1560 				update_search_tbl_counter = 1;
1561 				goto out;
1562 			}
1563 			break;
1564 		case IWL_MIMO2_SWITCH_SISO_A:
1565 		case IWL_MIMO2_SWITCH_SISO_B:
1566 		case IWL_MIMO2_SWITCH_SISO_C:
1567 			IWL_DEBUG_RATE(priv, "LQ: MIMO2 switch to SISO\n");
1568 
1569 			/* Set up new search table for SISO */
1570 			memcpy(search_tbl, tbl, sz);
1571 
1572 			if (tbl->action == IWL_MIMO2_SWITCH_SISO_A)
1573 				search_tbl->ant_type = ANT_A;
1574 			else if (tbl->action == IWL_MIMO2_SWITCH_SISO_B)
1575 				search_tbl->ant_type = ANT_B;
1576 			else
1577 				search_tbl->ant_type = ANT_C;
1578 
1579 			if (!iwl4965_rs_is_valid_ant(valid_tx_ant,
1580 						search_tbl->ant_type))
1581 				break;
1582 
1583 			ret = iwl4965_rs_switch_to_siso(priv, lq_sta,
1584 						conf, sta,
1585 						 search_tbl, index);
1586 			if (!ret)
1587 				goto out;
1588 
1589 			break;
1590 
1591 		case IWL_MIMO2_SWITCH_GI:
1592 			if (!tbl->is_ht40 && !(ht_cap->cap &
1593 						IEEE80211_HT_CAP_SGI_20))
1594 				break;
1595 			if (tbl->is_ht40 && !(ht_cap->cap &
1596 						IEEE80211_HT_CAP_SGI_40))
1597 				break;
1598 
1599 			IWL_DEBUG_RATE(priv, "LQ: MIMO2 toggle SGI/NGI\n");
1600 
1601 			/* Set up new search table for MIMO2 */
1602 			memcpy(search_tbl, tbl, sz);
1603 			search_tbl->is_SGI = !tbl->is_SGI;
1604 			iwl4965_rs_set_expected_tpt_table(lq_sta, search_tbl);
1605 			/*
1606 			 * If active table already uses the fastest possible
1607 			 * modulation (dual stream with short guard interval),
1608 			 * and it's working well, there's no need to look
1609 			 * for a better type of modulation!
1610 			 */
1611 			if (tbl->is_SGI) {
1612 				s32 tpt = lq_sta->last_tpt / 100;
1613 				if (tpt >= search_tbl->expected_tpt[index])
1614 					break;
1615 			}
1616 			search_tbl->current_rate =
1617 				iwl4965_rate_n_flags_from_tbl(priv, search_tbl,
1618 						      index, is_green);
1619 			update_search_tbl_counter = 1;
1620 			goto out;
1621 
1622 		}
1623 		tbl->action++;
1624 		if (tbl->action > IWL_MIMO2_SWITCH_GI)
1625 			tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1626 
1627 		if (tbl->action == start_action)
1628 			break;
1629 	}
1630 	search_tbl->lq_type = LQ_NONE;
1631 	return 0;
1632  out:
1633 	lq_sta->search_better_tbl = 1;
1634 	tbl->action++;
1635 	if (tbl->action > IWL_MIMO2_SWITCH_GI)
1636 		tbl->action = IWL_MIMO2_SWITCH_ANTENNA1;
1637 	if (update_search_tbl_counter)
1638 		search_tbl->action = tbl->action;
1639 
1640 	return 0;
1641 
1642 }
1643 
1644 /*
1645  * Check whether we should continue using same modulation mode, or
1646  * begin search for a new mode, based on:
1647  * 1) # tx successes or failures while using this mode
1648  * 2) # times calling this function
1649  * 3) elapsed time in this mode (not used, for now)
1650  */
1651 static void
iwl4965_rs_stay_in_table(struct iwl_lq_sta * lq_sta,bool force_search)1652 iwl4965_rs_stay_in_table(struct iwl_lq_sta *lq_sta, bool force_search)
1653 {
1654 	struct iwl_scale_tbl_info *tbl;
1655 	int i;
1656 	int active_tbl;
1657 	int flush_interval_passed = 0;
1658 	struct iwl_priv *priv;
1659 
1660 	priv = lq_sta->drv;
1661 	active_tbl = lq_sta->active_tbl;
1662 
1663 	tbl = &(lq_sta->lq_info[active_tbl]);
1664 
1665 	/* If we've been disallowing search, see if we should now allow it */
1666 	if (lq_sta->stay_in_tbl) {
1667 
1668 		/* Elapsed time using current modulation mode */
1669 		if (lq_sta->flush_timer)
1670 			flush_interval_passed =
1671 			time_after(jiffies,
1672 					(unsigned long)(lq_sta->flush_timer +
1673 					IWL_RATE_SCALE_FLUSH_INTVL));
1674 
1675 		/*
1676 		 * Check if we should allow search for new modulation mode.
1677 		 * If many frames have failed or succeeded, or we've used
1678 		 * this same modulation for a long time, allow search, and
1679 		 * reset history stats that keep track of whether we should
1680 		 * allow a new search.  Also (below) reset all bitmaps and
1681 		 * stats in active history.
1682 		 */
1683 		if (force_search ||
1684 		    (lq_sta->total_failed > lq_sta->max_failure_limit) ||
1685 		    (lq_sta->total_success > lq_sta->max_success_limit) ||
1686 		    ((!lq_sta->search_better_tbl) && (lq_sta->flush_timer)
1687 		     && (flush_interval_passed))) {
1688 			IWL_DEBUG_RATE(priv, "LQ: stay is expired %d %d %d\n:",
1689 				     lq_sta->total_failed,
1690 				     lq_sta->total_success,
1691 				     flush_interval_passed);
1692 
1693 			/* Allow search for new mode */
1694 			lq_sta->stay_in_tbl = 0;	/* only place reset */
1695 			lq_sta->total_failed = 0;
1696 			lq_sta->total_success = 0;
1697 			lq_sta->flush_timer = 0;
1698 
1699 		/*
1700 		 * Else if we've used this modulation mode enough repetitions
1701 		 * (regardless of elapsed time or success/failure), reset
1702 		 * history bitmaps and rate-specific stats for all rates in
1703 		 * active table.
1704 		 */
1705 		} else {
1706 			lq_sta->table_count++;
1707 			if (lq_sta->table_count >=
1708 			    lq_sta->table_count_limit) {
1709 				lq_sta->table_count = 0;
1710 
1711 				IWL_DEBUG_RATE(priv,
1712 					"LQ: stay in table clear win\n");
1713 				for (i = 0; i < IWL_RATE_COUNT; i++)
1714 					iwl4965_rs_rate_scale_clear_window(
1715 						&(tbl->win[i]));
1716 			}
1717 		}
1718 
1719 		/* If transitioning to allow "search", reset all history
1720 		 * bitmaps and stats in active table (this will become the new
1721 		 * "search" table). */
1722 		if (!lq_sta->stay_in_tbl) {
1723 			for (i = 0; i < IWL_RATE_COUNT; i++)
1724 				iwl4965_rs_rate_scale_clear_window(
1725 							&(tbl->win[i]));
1726 		}
1727 	}
1728 }
1729 
1730 /*
1731  * setup rate table in uCode
1732  * return rate_n_flags as used in the table
1733  */
iwl4965_rs_update_rate_tbl(struct iwl_priv * priv,struct iwl_rxon_context * ctx,struct iwl_lq_sta * lq_sta,struct iwl_scale_tbl_info * tbl,int index,u8 is_green)1734 static u32 iwl4965_rs_update_rate_tbl(struct iwl_priv *priv,
1735 			      struct iwl_rxon_context *ctx,
1736 				struct iwl_lq_sta *lq_sta,
1737 				struct iwl_scale_tbl_info *tbl,
1738 				int index, u8 is_green)
1739 {
1740 	u32 rate;
1741 
1742 	/* Update uCode's rate table. */
1743 	rate = iwl4965_rate_n_flags_from_tbl(priv, tbl, index, is_green);
1744 	iwl4965_rs_fill_link_cmd(priv, lq_sta, rate);
1745 	iwl_legacy_send_lq_cmd(priv, ctx, &lq_sta->lq, CMD_ASYNC, false);
1746 
1747 	return rate;
1748 }
1749 
1750 /*
1751  * Do rate scaling and search for new modulation mode.
1752  */
iwl4965_rs_rate_scale_perform(struct iwl_priv * priv,struct sk_buff * skb,struct ieee80211_sta * sta,struct iwl_lq_sta * lq_sta)1753 static void iwl4965_rs_rate_scale_perform(struct iwl_priv *priv,
1754 				  struct sk_buff *skb,
1755 				  struct ieee80211_sta *sta,
1756 				  struct iwl_lq_sta *lq_sta)
1757 {
1758 	struct ieee80211_hw *hw = priv->hw;
1759 	struct ieee80211_conf *conf = &hw->conf;
1760 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1761 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1762 	int low = IWL_RATE_INVALID;
1763 	int high = IWL_RATE_INVALID;
1764 	int index;
1765 	int i;
1766 	struct iwl_rate_scale_data *window = NULL;
1767 	int current_tpt = IWL_INVALID_VALUE;
1768 	int low_tpt = IWL_INVALID_VALUE;
1769 	int high_tpt = IWL_INVALID_VALUE;
1770 	u32 fail_count;
1771 	s8 scale_action = 0;
1772 	u16 rate_mask;
1773 	u8 update_lq = 0;
1774 	struct iwl_scale_tbl_info *tbl, *tbl1;
1775 	u16 rate_scale_index_msk = 0;
1776 	u32 rate;
1777 	u8 is_green = 0;
1778 	u8 active_tbl = 0;
1779 	u8 done_search = 0;
1780 	u16 high_low;
1781 	s32 sr;
1782 	u8 tid = MAX_TID_COUNT;
1783 	struct iwl_tid_data *tid_data;
1784 	struct iwl_station_priv *sta_priv = (void *)sta->drv_priv;
1785 	struct iwl_rxon_context *ctx = sta_priv->common.ctx;
1786 
1787 	IWL_DEBUG_RATE(priv, "rate scale calculate new rate for skb\n");
1788 
1789 	/* Send management frames and NO_ACK data using lowest rate. */
1790 	/* TODO: this could probably be improved.. */
1791 	if (!ieee80211_is_data(hdr->frame_control) ||
1792 	    info->flags & IEEE80211_TX_CTL_NO_ACK)
1793 		return;
1794 
1795 	if (!sta || !lq_sta)
1796 		return;
1797 
1798 	lq_sta->supp_rates = sta->supp_rates[lq_sta->band];
1799 
1800 	tid = iwl4965_rs_tl_add_packet(lq_sta, hdr);
1801 	if ((tid != MAX_TID_COUNT) && (lq_sta->tx_agg_tid_en & (1 << tid))) {
1802 		tid_data = &priv->stations[lq_sta->lq.sta_id].tid[tid];
1803 		if (tid_data->agg.state == IWL_AGG_OFF)
1804 			lq_sta->is_agg = 0;
1805 		else
1806 			lq_sta->is_agg = 1;
1807 	} else
1808 		lq_sta->is_agg = 0;
1809 
1810 	/*
1811 	 * Select rate-scale / modulation-mode table to work with in
1812 	 * the rest of this function:  "search" if searching for better
1813 	 * modulation mode, or "active" if doing rate scaling within a mode.
1814 	 */
1815 	if (!lq_sta->search_better_tbl)
1816 		active_tbl = lq_sta->active_tbl;
1817 	else
1818 		active_tbl = 1 - lq_sta->active_tbl;
1819 
1820 	tbl = &(lq_sta->lq_info[active_tbl]);
1821 	if (is_legacy(tbl->lq_type))
1822 		lq_sta->is_green = 0;
1823 	else
1824 		lq_sta->is_green = iwl4965_rs_use_green(sta);
1825 	is_green = lq_sta->is_green;
1826 
1827 	/* current tx rate */
1828 	index = lq_sta->last_txrate_idx;
1829 
1830 	IWL_DEBUG_RATE(priv, "Rate scale index %d for type %d\n", index,
1831 		       tbl->lq_type);
1832 
1833 	/* rates available for this association, and for modulation mode */
1834 	rate_mask = iwl4965_rs_get_supported_rates(lq_sta, hdr, tbl->lq_type);
1835 
1836 	IWL_DEBUG_RATE(priv, "mask 0x%04X\n", rate_mask);
1837 
1838 	/* mask with station rate restriction */
1839 	if (is_legacy(tbl->lq_type)) {
1840 		if (lq_sta->band == IEEE80211_BAND_5GHZ)
1841 			/* supp_rates has no CCK bits in A mode */
1842 			rate_scale_index_msk = (u16) (rate_mask &
1843 				(lq_sta->supp_rates << IWL_FIRST_OFDM_RATE));
1844 		else
1845 			rate_scale_index_msk = (u16) (rate_mask &
1846 						      lq_sta->supp_rates);
1847 
1848 	} else
1849 		rate_scale_index_msk = rate_mask;
1850 
1851 	if (!rate_scale_index_msk)
1852 		rate_scale_index_msk = rate_mask;
1853 
1854 	if (!((1 << index) & rate_scale_index_msk)) {
1855 		IWL_ERR(priv, "Current Rate is not valid\n");
1856 		if (lq_sta->search_better_tbl) {
1857 			/* revert to active table if search table is not valid*/
1858 			tbl->lq_type = LQ_NONE;
1859 			lq_sta->search_better_tbl = 0;
1860 			tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
1861 			/* get "active" rate info */
1862 			index = iwl4965_hwrate_to_plcp_idx(tbl->current_rate);
1863 			rate = iwl4965_rs_update_rate_tbl(priv, ctx, lq_sta,
1864 						  tbl, index, is_green);
1865 		}
1866 		return;
1867 	}
1868 
1869 	/* Get expected throughput table and history window for current rate */
1870 	if (!tbl->expected_tpt) {
1871 		IWL_ERR(priv, "tbl->expected_tpt is NULL\n");
1872 		return;
1873 	}
1874 
1875 	/* force user max rate if set by user */
1876 	if ((lq_sta->max_rate_idx != -1) &&
1877 	    (lq_sta->max_rate_idx < index)) {
1878 		index = lq_sta->max_rate_idx;
1879 		update_lq = 1;
1880 		window = &(tbl->win[index]);
1881 		goto lq_update;
1882 	}
1883 
1884 	window = &(tbl->win[index]);
1885 
1886 	/*
1887 	 * If there is not enough history to calculate actual average
1888 	 * throughput, keep analyzing results of more tx frames, without
1889 	 * changing rate or mode (bypass most of the rest of this function).
1890 	 * Set up new rate table in uCode only if old rate is not supported
1891 	 * in current association (use new rate found above).
1892 	 */
1893 	fail_count = window->counter - window->success_counter;
1894 	if ((fail_count < IWL_RATE_MIN_FAILURE_TH) &&
1895 			(window->success_counter < IWL_RATE_MIN_SUCCESS_TH)) {
1896 		IWL_DEBUG_RATE(priv, "LQ: still below TH. succ=%d total=%d "
1897 			       "for index %d\n",
1898 			       window->success_counter, window->counter, index);
1899 
1900 		/* Can't calculate this yet; not enough history */
1901 		window->average_tpt = IWL_INVALID_VALUE;
1902 
1903 		/* Should we stay with this modulation mode,
1904 		 * or search for a new one? */
1905 		iwl4965_rs_stay_in_table(lq_sta, false);
1906 
1907 		goto out;
1908 	}
1909 	/* Else we have enough samples; calculate estimate of
1910 	 * actual average throughput */
1911 	if (window->average_tpt != ((window->success_ratio *
1912 			tbl->expected_tpt[index] + 64) / 128)) {
1913 		IWL_ERR(priv,
1914 			 "expected_tpt should have been calculated by now\n");
1915 		window->average_tpt = ((window->success_ratio *
1916 					tbl->expected_tpt[index] + 64) / 128);
1917 	}
1918 
1919 	/* If we are searching for better modulation mode, check success. */
1920 	if (lq_sta->search_better_tbl) {
1921 		/* If good success, continue using the "search" mode;
1922 		 * no need to send new link quality command, since we're
1923 		 * continuing to use the setup that we've been trying. */
1924 		if (window->average_tpt > lq_sta->last_tpt) {
1925 
1926 			IWL_DEBUG_RATE(priv, "LQ: SWITCHING TO NEW TABLE "
1927 					"suc=%d cur-tpt=%d old-tpt=%d\n",
1928 					window->success_ratio,
1929 					window->average_tpt,
1930 					lq_sta->last_tpt);
1931 
1932 			if (!is_legacy(tbl->lq_type))
1933 				lq_sta->enable_counter = 1;
1934 
1935 			/* Swap tables; "search" becomes "active" */
1936 			lq_sta->active_tbl = active_tbl;
1937 			current_tpt = window->average_tpt;
1938 
1939 		/* Else poor success; go back to mode in "active" table */
1940 		} else {
1941 
1942 			IWL_DEBUG_RATE(priv, "LQ: GOING BACK TO THE OLD TABLE "
1943 					"suc=%d cur-tpt=%d old-tpt=%d\n",
1944 					window->success_ratio,
1945 					window->average_tpt,
1946 					lq_sta->last_tpt);
1947 
1948 			/* Nullify "search" table */
1949 			tbl->lq_type = LQ_NONE;
1950 
1951 			/* Revert to "active" table */
1952 			active_tbl = lq_sta->active_tbl;
1953 			tbl = &(lq_sta->lq_info[active_tbl]);
1954 
1955 			/* Revert to "active" rate and throughput info */
1956 			index = iwl4965_hwrate_to_plcp_idx(tbl->current_rate);
1957 			current_tpt = lq_sta->last_tpt;
1958 
1959 			/* Need to set up a new rate table in uCode */
1960 			update_lq = 1;
1961 		}
1962 
1963 		/* Either way, we've made a decision; modulation mode
1964 		 * search is done, allow rate adjustment next time. */
1965 		lq_sta->search_better_tbl = 0;
1966 		done_search = 1;	/* Don't switch modes below! */
1967 		goto lq_update;
1968 	}
1969 
1970 	/* (Else) not in search of better modulation mode, try for better
1971 	 * starting rate, while staying in this mode. */
1972 	high_low = iwl4965_rs_get_adjacent_rate(priv, index,
1973 					rate_scale_index_msk,
1974 					tbl->lq_type);
1975 	low = high_low & 0xff;
1976 	high = (high_low >> 8) & 0xff;
1977 
1978 	/* If user set max rate, dont allow higher than user constrain */
1979 	if ((lq_sta->max_rate_idx != -1) &&
1980 	    (lq_sta->max_rate_idx < high))
1981 		high = IWL_RATE_INVALID;
1982 
1983 	sr = window->success_ratio;
1984 
1985 	/* Collect measured throughputs for current and adjacent rates */
1986 	current_tpt = window->average_tpt;
1987 	if (low != IWL_RATE_INVALID)
1988 		low_tpt = tbl->win[low].average_tpt;
1989 	if (high != IWL_RATE_INVALID)
1990 		high_tpt = tbl->win[high].average_tpt;
1991 
1992 	scale_action = 0;
1993 
1994 	/* Too many failures, decrease rate */
1995 	if ((sr <= IWL_RATE_DECREASE_TH) || (current_tpt == 0)) {
1996 		IWL_DEBUG_RATE(priv,
1997 			"decrease rate because of low success_ratio\n");
1998 		scale_action = -1;
1999 
2000 	/* No throughput measured yet for adjacent rates; try increase. */
2001 	} else if ((low_tpt == IWL_INVALID_VALUE) &&
2002 		   (high_tpt == IWL_INVALID_VALUE)) {
2003 
2004 		if (high != IWL_RATE_INVALID && sr >= IWL_RATE_INCREASE_TH)
2005 			scale_action = 1;
2006 		else if (low != IWL_RATE_INVALID)
2007 			scale_action = 0;
2008 	}
2009 
2010 	/* Both adjacent throughputs are measured, but neither one has better
2011 	 * throughput; we're using the best rate, don't change it! */
2012 	else if ((low_tpt != IWL_INVALID_VALUE) &&
2013 		 (high_tpt != IWL_INVALID_VALUE) &&
2014 		 (low_tpt < current_tpt) &&
2015 		 (high_tpt < current_tpt))
2016 		scale_action = 0;
2017 
2018 	/* At least one adjacent rate's throughput is measured,
2019 	 * and may have better performance. */
2020 	else {
2021 		/* Higher adjacent rate's throughput is measured */
2022 		if (high_tpt != IWL_INVALID_VALUE) {
2023 			/* Higher rate has better throughput */
2024 			if (high_tpt > current_tpt &&
2025 					sr >= IWL_RATE_INCREASE_TH) {
2026 				scale_action = 1;
2027 			} else {
2028 				scale_action = 0;
2029 			}
2030 
2031 		/* Lower adjacent rate's throughput is measured */
2032 		} else if (low_tpt != IWL_INVALID_VALUE) {
2033 			/* Lower rate has better throughput */
2034 			if (low_tpt > current_tpt) {
2035 				IWL_DEBUG_RATE(priv,
2036 				    "decrease rate because of low tpt\n");
2037 				scale_action = -1;
2038 			} else if (sr >= IWL_RATE_INCREASE_TH) {
2039 				scale_action = 1;
2040 			}
2041 		}
2042 	}
2043 
2044 	/* Sanity check; asked for decrease, but success rate or throughput
2045 	 * has been good at old rate.  Don't change it. */
2046 	if ((scale_action == -1) && (low != IWL_RATE_INVALID) &&
2047 		    ((sr > IWL_RATE_HIGH_TH) ||
2048 		     (current_tpt > (100 * tbl->expected_tpt[low]))))
2049 		scale_action = 0;
2050 
2051 	switch (scale_action) {
2052 	case -1:
2053 		/* Decrease starting rate, update uCode's rate table */
2054 		if (low != IWL_RATE_INVALID) {
2055 			update_lq = 1;
2056 			index = low;
2057 		}
2058 
2059 		break;
2060 	case 1:
2061 		/* Increase starting rate, update uCode's rate table */
2062 		if (high != IWL_RATE_INVALID) {
2063 			update_lq = 1;
2064 			index = high;
2065 		}
2066 
2067 		break;
2068 	case 0:
2069 		/* No change */
2070 	default:
2071 		break;
2072 	}
2073 
2074 	IWL_DEBUG_RATE(priv, "choose rate scale index %d action %d low %d "
2075 		    "high %d type %d\n",
2076 		     index, scale_action, low, high, tbl->lq_type);
2077 
2078 lq_update:
2079 	/* Replace uCode's rate table for the destination station. */
2080 	if (update_lq)
2081 		rate = iwl4965_rs_update_rate_tbl(priv, ctx, lq_sta,
2082 					  tbl, index, is_green);
2083 
2084 	/* Should we stay with this modulation mode,
2085 	 * or search for a new one? */
2086 	 iwl4965_rs_stay_in_table(lq_sta, false);
2087 
2088 	/*
2089 	 * Search for new modulation mode if we're:
2090 	 * 1)  Not changing rates right now
2091 	 * 2)  Not just finishing up a search
2092 	 * 3)  Allowing a new search
2093 	 */
2094 	if (!update_lq && !done_search &&
2095 		!lq_sta->stay_in_tbl && window->counter) {
2096 		/* Save current throughput to compare with "search" throughput*/
2097 		lq_sta->last_tpt = current_tpt;
2098 
2099 		/* Select a new "search" modulation mode to try.
2100 		 * If one is found, set up the new "search" table. */
2101 		if (is_legacy(tbl->lq_type))
2102 			iwl4965_rs_move_legacy_other(priv, lq_sta,
2103 							conf, sta, index);
2104 		else if (is_siso(tbl->lq_type))
2105 			iwl4965_rs_move_siso_to_other(priv, lq_sta,
2106 							conf, sta, index);
2107 		else /* (is_mimo2(tbl->lq_type)) */
2108 			iwl4965_rs_move_mimo2_to_other(priv, lq_sta,
2109 							conf, sta, index);
2110 
2111 		/* If new "search" mode was selected, set up in uCode table */
2112 		if (lq_sta->search_better_tbl) {
2113 			/* Access the "search" table, clear its history. */
2114 			tbl = &(lq_sta->lq_info[(1 - lq_sta->active_tbl)]);
2115 			for (i = 0; i < IWL_RATE_COUNT; i++)
2116 				iwl4965_rs_rate_scale_clear_window(
2117 							&(tbl->win[i]));
2118 
2119 			/* Use new "search" start rate */
2120 			index = iwl4965_hwrate_to_plcp_idx(tbl->current_rate);
2121 
2122 			IWL_DEBUG_RATE(priv,
2123 				"Switch current  mcs: %X index: %d\n",
2124 				     tbl->current_rate, index);
2125 			iwl4965_rs_fill_link_cmd(priv, lq_sta,
2126 						tbl->current_rate);
2127 			iwl_legacy_send_lq_cmd(priv, ctx,
2128 						&lq_sta->lq, CMD_ASYNC, false);
2129 		} else
2130 			done_search = 1;
2131 	}
2132 
2133 	if (done_search && !lq_sta->stay_in_tbl) {
2134 		/* If the "active" (non-search) mode was legacy,
2135 		 * and we've tried switching antennas,
2136 		 * but we haven't been able to try HT modes (not available),
2137 		 * stay with best antenna legacy modulation for a while
2138 		 * before next round of mode comparisons. */
2139 		tbl1 = &(lq_sta->lq_info[lq_sta->active_tbl]);
2140 		if (is_legacy(tbl1->lq_type) && !conf_is_ht(conf) &&
2141 		    lq_sta->action_counter > tbl1->max_search) {
2142 			IWL_DEBUG_RATE(priv, "LQ: STAY in legacy table\n");
2143 			iwl4965_rs_set_stay_in_table(priv, 1, lq_sta);
2144 		}
2145 
2146 		/* If we're in an HT mode, and all 3 mode switch actions
2147 		 * have been tried and compared, stay in this best modulation
2148 		 * mode for a while before next round of mode comparisons. */
2149 		if (lq_sta->enable_counter &&
2150 		    (lq_sta->action_counter >= tbl1->max_search)) {
2151 			if ((lq_sta->last_tpt > IWL_AGG_TPT_THREHOLD) &&
2152 			    (lq_sta->tx_agg_tid_en & (1 << tid)) &&
2153 			    (tid != MAX_TID_COUNT)) {
2154 				tid_data =
2155 				   &priv->stations[lq_sta->lq.sta_id].tid[tid];
2156 				if (tid_data->agg.state == IWL_AGG_OFF) {
2157 					IWL_DEBUG_RATE(priv,
2158 						       "try to aggregate tid %d\n",
2159 						       tid);
2160 					iwl4965_rs_tl_turn_on_agg(priv, tid,
2161 							  lq_sta, sta);
2162 				}
2163 			}
2164 			iwl4965_rs_set_stay_in_table(priv, 0, lq_sta);
2165 		}
2166 	}
2167 
2168 out:
2169 	tbl->current_rate = iwl4965_rate_n_flags_from_tbl(priv, tbl,
2170 							index, is_green);
2171 	i = index;
2172 	lq_sta->last_txrate_idx = i;
2173 }
2174 
2175 /**
2176  * iwl4965_rs_initialize_lq - Initialize a station's hardware rate table
2177  *
2178  * The uCode's station table contains a table of fallback rates
2179  * for automatic fallback during transmission.
2180  *
2181  * NOTE: This sets up a default set of values.  These will be replaced later
2182  *       if the driver's iwl-4965-rs rate scaling algorithm is used, instead of
2183  *       rc80211_simple.
2184  *
2185  * NOTE: Run REPLY_ADD_STA command to set up station table entry, before
2186  *       calling this function (which runs REPLY_TX_LINK_QUALITY_CMD,
2187  *       which requires station table entry to exist).
2188  */
iwl4965_rs_initialize_lq(struct iwl_priv * priv,struct ieee80211_conf * conf,struct ieee80211_sta * sta,struct iwl_lq_sta * lq_sta)2189 static void iwl4965_rs_initialize_lq(struct iwl_priv *priv,
2190 			     struct ieee80211_conf *conf,
2191 			     struct ieee80211_sta *sta,
2192 			     struct iwl_lq_sta *lq_sta)
2193 {
2194 	struct iwl_scale_tbl_info *tbl;
2195 	int rate_idx;
2196 	int i;
2197 	u32 rate;
2198 	u8 use_green = iwl4965_rs_use_green(sta);
2199 	u8 active_tbl = 0;
2200 	u8 valid_tx_ant;
2201 	struct iwl_station_priv *sta_priv;
2202 	struct iwl_rxon_context *ctx;
2203 
2204 	if (!sta || !lq_sta)
2205 		return;
2206 
2207 	sta_priv = (void *)sta->drv_priv;
2208 	ctx = sta_priv->common.ctx;
2209 
2210 	i = lq_sta->last_txrate_idx;
2211 
2212 	valid_tx_ant = priv->hw_params.valid_tx_ant;
2213 
2214 	if (!lq_sta->search_better_tbl)
2215 		active_tbl = lq_sta->active_tbl;
2216 	else
2217 		active_tbl = 1 - lq_sta->active_tbl;
2218 
2219 	tbl = &(lq_sta->lq_info[active_tbl]);
2220 
2221 	if ((i < 0) || (i >= IWL_RATE_COUNT))
2222 		i = 0;
2223 
2224 	rate = iwlegacy_rates[i].plcp;
2225 	tbl->ant_type = iwl4965_first_antenna(valid_tx_ant);
2226 	rate |= tbl->ant_type << RATE_MCS_ANT_POS;
2227 
2228 	if (i >= IWL_FIRST_CCK_RATE && i <= IWL_LAST_CCK_RATE)
2229 		rate |= RATE_MCS_CCK_MSK;
2230 
2231 	iwl4965_rs_get_tbl_info_from_mcs(rate, priv->band, tbl, &rate_idx);
2232 	if (!iwl4965_rs_is_valid_ant(valid_tx_ant, tbl->ant_type))
2233 		iwl4965_rs_toggle_antenna(valid_tx_ant, &rate, tbl);
2234 
2235 	rate = iwl4965_rate_n_flags_from_tbl(priv, tbl, rate_idx, use_green);
2236 	tbl->current_rate = rate;
2237 	iwl4965_rs_set_expected_tpt_table(lq_sta, tbl);
2238 	iwl4965_rs_fill_link_cmd(NULL, lq_sta, rate);
2239 	priv->stations[lq_sta->lq.sta_id].lq = &lq_sta->lq;
2240 	iwl_legacy_send_lq_cmd(priv, ctx, &lq_sta->lq, CMD_SYNC, true);
2241 }
2242 
2243 static void
iwl4965_rs_get_rate(void * priv_r,struct ieee80211_sta * sta,void * priv_sta,struct ieee80211_tx_rate_control * txrc)2244 iwl4965_rs_get_rate(void *priv_r, struct ieee80211_sta *sta, void *priv_sta,
2245 			struct ieee80211_tx_rate_control *txrc)
2246 {
2247 
2248 	struct sk_buff *skb = txrc->skb;
2249 	struct ieee80211_supported_band *sband = txrc->sband;
2250 	struct iwl_priv *priv __maybe_unused = (struct iwl_priv *)priv_r;
2251 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2252 	struct iwl_lq_sta *lq_sta = priv_sta;
2253 	int rate_idx;
2254 
2255 	IWL_DEBUG_RATE_LIMIT(priv, "rate scale calculate new rate for skb\n");
2256 
2257 	/* Get max rate if user set max rate */
2258 	if (lq_sta) {
2259 		lq_sta->max_rate_idx = txrc->max_rate_idx;
2260 		if ((sband->band == IEEE80211_BAND_5GHZ) &&
2261 		    (lq_sta->max_rate_idx != -1))
2262 			lq_sta->max_rate_idx += IWL_FIRST_OFDM_RATE;
2263 		if ((lq_sta->max_rate_idx < 0) ||
2264 		    (lq_sta->max_rate_idx >= IWL_RATE_COUNT))
2265 			lq_sta->max_rate_idx = -1;
2266 	}
2267 
2268 	/* Treat uninitialized rate scaling data same as non-existing. */
2269 	if (lq_sta && !lq_sta->drv) {
2270 		IWL_DEBUG_RATE(priv, "Rate scaling not initialized yet.\n");
2271 		priv_sta = NULL;
2272 	}
2273 
2274 	/* Send management frames and NO_ACK data using lowest rate. */
2275 	if (rate_control_send_low(sta, priv_sta, txrc))
2276 		return;
2277 
2278 	rate_idx  = lq_sta->last_txrate_idx;
2279 
2280 	if (lq_sta->last_rate_n_flags & RATE_MCS_HT_MSK) {
2281 		rate_idx -= IWL_FIRST_OFDM_RATE;
2282 		/* 6M and 9M shared same MCS index */
2283 		rate_idx = (rate_idx > 0) ? (rate_idx - 1) : 0;
2284 		if (iwl4965_rs_extract_rate(lq_sta->last_rate_n_flags) >=
2285 			 IWL_RATE_MIMO2_6M_PLCP)
2286 			rate_idx = rate_idx + MCS_INDEX_PER_STREAM;
2287 		info->control.rates[0].flags = IEEE80211_TX_RC_MCS;
2288 		if (lq_sta->last_rate_n_flags & RATE_MCS_SGI_MSK)
2289 			info->control.rates[0].flags |=
2290 					IEEE80211_TX_RC_SHORT_GI;
2291 		if (lq_sta->last_rate_n_flags & RATE_MCS_DUP_MSK)
2292 			info->control.rates[0].flags |=
2293 					IEEE80211_TX_RC_DUP_DATA;
2294 		if (lq_sta->last_rate_n_flags & RATE_MCS_HT40_MSK)
2295 			info->control.rates[0].flags |=
2296 					IEEE80211_TX_RC_40_MHZ_WIDTH;
2297 		if (lq_sta->last_rate_n_flags & RATE_MCS_GF_MSK)
2298 			info->control.rates[0].flags |=
2299 					IEEE80211_TX_RC_GREEN_FIELD;
2300 	} else {
2301 		/* Check for invalid rates */
2302 		if ((rate_idx < 0) || (rate_idx >= IWL_RATE_COUNT_LEGACY) ||
2303 				((sband->band == IEEE80211_BAND_5GHZ) &&
2304 				 (rate_idx < IWL_FIRST_OFDM_RATE)))
2305 			rate_idx = rate_lowest_index(sband, sta);
2306 		/* On valid 5 GHz rate, adjust index */
2307 		else if (sband->band == IEEE80211_BAND_5GHZ)
2308 			rate_idx -= IWL_FIRST_OFDM_RATE;
2309 		info->control.rates[0].flags = 0;
2310 	}
2311 	info->control.rates[0].idx = rate_idx;
2312 
2313 }
2314 
iwl4965_rs_alloc_sta(void * priv_rate,struct ieee80211_sta * sta,gfp_t gfp)2315 static void *iwl4965_rs_alloc_sta(void *priv_rate, struct ieee80211_sta *sta,
2316 			  gfp_t gfp)
2317 {
2318 	struct iwl_lq_sta *lq_sta;
2319 	struct iwl_station_priv *sta_priv =
2320 				(struct iwl_station_priv *) sta->drv_priv;
2321 	struct iwl_priv *priv;
2322 
2323 	priv = (struct iwl_priv *)priv_rate;
2324 	IWL_DEBUG_RATE(priv, "create station rate scale window\n");
2325 
2326 	lq_sta = &sta_priv->lq_sta;
2327 
2328 	return lq_sta;
2329 }
2330 
2331 /*
2332  * Called after adding a new station to initialize rate scaling
2333  */
2334 void
iwl4965_rs_rate_init(struct iwl_priv * priv,struct ieee80211_sta * sta,u8 sta_id)2335 iwl4965_rs_rate_init(struct iwl_priv *priv,
2336 			struct ieee80211_sta *sta,
2337 			u8 sta_id)
2338 {
2339 	int i, j;
2340 	struct ieee80211_hw *hw = priv->hw;
2341 	struct ieee80211_conf *conf = &priv->hw->conf;
2342 	struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
2343 	struct iwl_station_priv *sta_priv;
2344 	struct iwl_lq_sta *lq_sta;
2345 	struct ieee80211_supported_band *sband;
2346 
2347 	sta_priv = (struct iwl_station_priv *) sta->drv_priv;
2348 	lq_sta = &sta_priv->lq_sta;
2349 	sband = hw->wiphy->bands[conf->channel->band];
2350 
2351 
2352 	lq_sta->lq.sta_id = sta_id;
2353 
2354 	for (j = 0; j < LQ_SIZE; j++)
2355 		for (i = 0; i < IWL_RATE_COUNT; i++)
2356 			iwl4965_rs_rate_scale_clear_window(
2357 					&lq_sta->lq_info[j].win[i]);
2358 
2359 	lq_sta->flush_timer = 0;
2360 	lq_sta->supp_rates = sta->supp_rates[sband->band];
2361 	for (j = 0; j < LQ_SIZE; j++)
2362 		for (i = 0; i < IWL_RATE_COUNT; i++)
2363 			iwl4965_rs_rate_scale_clear_window(
2364 					&lq_sta->lq_info[j].win[i]);
2365 
2366 	IWL_DEBUG_RATE(priv, "LQ:"
2367 			"*** rate scale station global init for station %d ***\n",
2368 		       sta_id);
2369 	/* TODO: what is a good starting rate for STA? About middle? Maybe not
2370 	 * the lowest or the highest rate.. Could consider using RSSI from
2371 	 * previous packets? Need to have IEEE 802.1X auth succeed immediately
2372 	 * after assoc.. */
2373 
2374 	lq_sta->is_dup = 0;
2375 	lq_sta->max_rate_idx = -1;
2376 	lq_sta->missed_rate_counter = IWL_MISSED_RATE_MAX;
2377 	lq_sta->is_green = iwl4965_rs_use_green(sta);
2378 	lq_sta->active_legacy_rate = priv->active_rate & ~(0x1000);
2379 	lq_sta->band = priv->band;
2380 	/*
2381 	 * active_siso_rate mask includes 9 MBits (bit 5), and CCK (bits 0-3),
2382 	 * supp_rates[] does not; shift to convert format, force 9 MBits off.
2383 	 */
2384 	lq_sta->active_siso_rate = ht_cap->mcs.rx_mask[0] << 1;
2385 	lq_sta->active_siso_rate |= ht_cap->mcs.rx_mask[0] & 0x1;
2386 	lq_sta->active_siso_rate &= ~((u16)0x2);
2387 	lq_sta->active_siso_rate <<= IWL_FIRST_OFDM_RATE;
2388 
2389 	/* Same here */
2390 	lq_sta->active_mimo2_rate = ht_cap->mcs.rx_mask[1] << 1;
2391 	lq_sta->active_mimo2_rate |= ht_cap->mcs.rx_mask[1] & 0x1;
2392 	lq_sta->active_mimo2_rate &= ~((u16)0x2);
2393 	lq_sta->active_mimo2_rate <<= IWL_FIRST_OFDM_RATE;
2394 
2395 	/* These values will be overridden later */
2396 	lq_sta->lq.general_params.single_stream_ant_msk =
2397 		iwl4965_first_antenna(priv->hw_params.valid_tx_ant);
2398 	lq_sta->lq.general_params.dual_stream_ant_msk =
2399 		priv->hw_params.valid_tx_ant &
2400 		~iwl4965_first_antenna(priv->hw_params.valid_tx_ant);
2401 	if (!lq_sta->lq.general_params.dual_stream_ant_msk) {
2402 		lq_sta->lq.general_params.dual_stream_ant_msk = ANT_AB;
2403 	} else if (iwl4965_num_of_ant(priv->hw_params.valid_tx_ant) == 2) {
2404 		lq_sta->lq.general_params.dual_stream_ant_msk =
2405 			priv->hw_params.valid_tx_ant;
2406 	}
2407 
2408 	/* as default allow aggregation for all tids */
2409 	lq_sta->tx_agg_tid_en = IWL_AGG_ALL_TID;
2410 	lq_sta->drv = priv;
2411 
2412 	/* Set last_txrate_idx to lowest rate */
2413 	lq_sta->last_txrate_idx = rate_lowest_index(sband, sta);
2414 	if (sband->band == IEEE80211_BAND_5GHZ)
2415 		lq_sta->last_txrate_idx += IWL_FIRST_OFDM_RATE;
2416 	lq_sta->is_agg = 0;
2417 
2418 #ifdef CONFIG_MAC80211_DEBUGFS
2419 	lq_sta->dbg_fixed_rate = 0;
2420 #endif
2421 
2422 	iwl4965_rs_initialize_lq(priv, conf, sta, lq_sta);
2423 }
2424 
iwl4965_rs_fill_link_cmd(struct iwl_priv * priv,struct iwl_lq_sta * lq_sta,u32 new_rate)2425 static void iwl4965_rs_fill_link_cmd(struct iwl_priv *priv,
2426 			     struct iwl_lq_sta *lq_sta, u32 new_rate)
2427 {
2428 	struct iwl_scale_tbl_info tbl_type;
2429 	int index = 0;
2430 	int rate_idx;
2431 	int repeat_rate = 0;
2432 	u8 ant_toggle_cnt = 0;
2433 	u8 use_ht_possible = 1;
2434 	u8 valid_tx_ant = 0;
2435 	struct iwl_link_quality_cmd *lq_cmd = &lq_sta->lq;
2436 
2437 	/* Override starting rate (index 0) if needed for debug purposes */
2438 	iwl4965_rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2439 
2440 	/* Interpret new_rate (rate_n_flags) */
2441 	iwl4965_rs_get_tbl_info_from_mcs(new_rate, lq_sta->band,
2442 				  &tbl_type, &rate_idx);
2443 
2444 	/* How many times should we repeat the initial rate? */
2445 	if (is_legacy(tbl_type.lq_type)) {
2446 		ant_toggle_cnt = 1;
2447 		repeat_rate = IWL_NUMBER_TRY;
2448 	} else {
2449 		repeat_rate = IWL_HT_NUMBER_TRY;
2450 	}
2451 
2452 	lq_cmd->general_params.mimo_delimiter =
2453 			is_mimo(tbl_type.lq_type) ? 1 : 0;
2454 
2455 	/* Fill 1st table entry (index 0) */
2456 	lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2457 
2458 	if (iwl4965_num_of_ant(tbl_type.ant_type) == 1) {
2459 		lq_cmd->general_params.single_stream_ant_msk =
2460 						tbl_type.ant_type;
2461 	} else if (iwl4965_num_of_ant(tbl_type.ant_type) == 2) {
2462 		lq_cmd->general_params.dual_stream_ant_msk =
2463 						tbl_type.ant_type;
2464 	} /* otherwise we don't modify the existing value */
2465 
2466 	index++;
2467 	repeat_rate--;
2468 	if (priv)
2469 		valid_tx_ant = priv->hw_params.valid_tx_ant;
2470 
2471 	/* Fill rest of rate table */
2472 	while (index < LINK_QUAL_MAX_RETRY_NUM) {
2473 		/* Repeat initial/next rate.
2474 		 * For legacy IWL_NUMBER_TRY == 1, this loop will not execute.
2475 		 * For HT IWL_HT_NUMBER_TRY == 3, this executes twice. */
2476 		while (repeat_rate > 0 && (index < LINK_QUAL_MAX_RETRY_NUM)) {
2477 			if (is_legacy(tbl_type.lq_type)) {
2478 				if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2479 					ant_toggle_cnt++;
2480 				else if (priv &&
2481 					 iwl4965_rs_toggle_antenna(valid_tx_ant,
2482 							&new_rate, &tbl_type))
2483 					ant_toggle_cnt = 1;
2484 			}
2485 
2486 			/* Override next rate if needed for debug purposes */
2487 			iwl4965_rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2488 
2489 			/* Fill next table entry */
2490 			lq_cmd->rs_table[index].rate_n_flags =
2491 					cpu_to_le32(new_rate);
2492 			repeat_rate--;
2493 			index++;
2494 		}
2495 
2496 		iwl4965_rs_get_tbl_info_from_mcs(new_rate,
2497 						lq_sta->band, &tbl_type,
2498 						&rate_idx);
2499 
2500 		/* Indicate to uCode which entries might be MIMO.
2501 		 * If initial rate was MIMO, this will finally end up
2502 		 * as (IWL_HT_NUMBER_TRY * 2), after 2nd pass, otherwise 0. */
2503 		if (is_mimo(tbl_type.lq_type))
2504 			lq_cmd->general_params.mimo_delimiter = index;
2505 
2506 		/* Get next rate */
2507 		new_rate = iwl4965_rs_get_lower_rate(lq_sta,
2508 					&tbl_type, rate_idx,
2509 					     use_ht_possible);
2510 
2511 		/* How many times should we repeat the next rate? */
2512 		if (is_legacy(tbl_type.lq_type)) {
2513 			if (ant_toggle_cnt < NUM_TRY_BEFORE_ANT_TOGGLE)
2514 				ant_toggle_cnt++;
2515 			else if (priv &&
2516 				 iwl4965_rs_toggle_antenna(valid_tx_ant,
2517 						   &new_rate, &tbl_type))
2518 				ant_toggle_cnt = 1;
2519 
2520 			repeat_rate = IWL_NUMBER_TRY;
2521 		} else {
2522 			repeat_rate = IWL_HT_NUMBER_TRY;
2523 		}
2524 
2525 		/* Don't allow HT rates after next pass.
2526 		 * iwl4965_rs_get_lower_rate() will change type to LQ_A or LQ_G. */
2527 		use_ht_possible = 0;
2528 
2529 		/* Override next rate if needed for debug purposes */
2530 		iwl4965_rs_dbgfs_set_mcs(lq_sta, &new_rate, index);
2531 
2532 		/* Fill next table entry */
2533 		lq_cmd->rs_table[index].rate_n_flags = cpu_to_le32(new_rate);
2534 
2535 		index++;
2536 		repeat_rate--;
2537 	}
2538 
2539 	lq_cmd->agg_params.agg_frame_cnt_limit = LINK_QUAL_AGG_FRAME_LIMIT_DEF;
2540 	lq_cmd->agg_params.agg_dis_start_th = LINK_QUAL_AGG_DISABLE_START_DEF;
2541 
2542 	lq_cmd->agg_params.agg_time_limit =
2543 		cpu_to_le16(LINK_QUAL_AGG_TIME_LIMIT_DEF);
2544 }
2545 
2546 static void
iwl4965_rs_alloc(struct ieee80211_hw * hw,struct dentry * debugfsdir)2547 *iwl4965_rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir)
2548 {
2549 	return hw->priv;
2550 }
2551 /* rate scale requires free function to be implemented */
iwl4965_rs_free(void * priv_rate)2552 static void iwl4965_rs_free(void *priv_rate)
2553 {
2554 	return;
2555 }
2556 
iwl4965_rs_free_sta(void * priv_r,struct ieee80211_sta * sta,void * priv_sta)2557 static void iwl4965_rs_free_sta(void *priv_r, struct ieee80211_sta *sta,
2558 			void *priv_sta)
2559 {
2560 	struct iwl_priv *priv __maybe_unused = priv_r;
2561 
2562 	IWL_DEBUG_RATE(priv, "enter\n");
2563 	IWL_DEBUG_RATE(priv, "leave\n");
2564 }
2565 
2566 
2567 #ifdef CONFIG_MAC80211_DEBUGFS
iwl4965_open_file_generic(struct inode * inode,struct file * file)2568 static int iwl4965_open_file_generic(struct inode *inode, struct file *file)
2569 {
2570 	file->private_data = inode->i_private;
2571 	return 0;
2572 }
iwl4965_rs_dbgfs_set_mcs(struct iwl_lq_sta * lq_sta,u32 * rate_n_flags,int index)2573 static void iwl4965_rs_dbgfs_set_mcs(struct iwl_lq_sta *lq_sta,
2574 			     u32 *rate_n_flags, int index)
2575 {
2576 	struct iwl_priv *priv;
2577 	u8 valid_tx_ant;
2578 	u8 ant_sel_tx;
2579 
2580 	priv = lq_sta->drv;
2581 	valid_tx_ant = priv->hw_params.valid_tx_ant;
2582 	if (lq_sta->dbg_fixed_rate) {
2583 		ant_sel_tx =
2584 		  ((lq_sta->dbg_fixed_rate & RATE_MCS_ANT_ABC_MSK)
2585 		  >> RATE_MCS_ANT_POS);
2586 		if ((valid_tx_ant & ant_sel_tx) == ant_sel_tx) {
2587 			*rate_n_flags = lq_sta->dbg_fixed_rate;
2588 			IWL_DEBUG_RATE(priv, "Fixed rate ON\n");
2589 		} else {
2590 			lq_sta->dbg_fixed_rate = 0;
2591 			IWL_ERR(priv,
2592 			    "Invalid antenna selection 0x%X, Valid is 0x%X\n",
2593 			    ant_sel_tx, valid_tx_ant);
2594 			IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2595 		}
2596 	} else {
2597 		IWL_DEBUG_RATE(priv, "Fixed rate OFF\n");
2598 	}
2599 }
2600 
iwl4965_rs_sta_dbgfs_scale_table_write(struct file * file,const char __user * user_buf,size_t count,loff_t * ppos)2601 static ssize_t iwl4965_rs_sta_dbgfs_scale_table_write(struct file *file,
2602 			const char __user *user_buf, size_t count, loff_t *ppos)
2603 {
2604 	struct iwl_lq_sta *lq_sta = file->private_data;
2605 	struct iwl_priv *priv;
2606 	char buf[64];
2607 	int buf_size;
2608 	u32 parsed_rate;
2609 	struct iwl_station_priv *sta_priv =
2610 		container_of(lq_sta, struct iwl_station_priv, lq_sta);
2611 	struct iwl_rxon_context *ctx = sta_priv->common.ctx;
2612 
2613 	priv = lq_sta->drv;
2614 	memset(buf, 0, sizeof(buf));
2615 	buf_size = min(count, sizeof(buf) -  1);
2616 	if (copy_from_user(buf, user_buf, buf_size))
2617 		return -EFAULT;
2618 
2619 	if (sscanf(buf, "%x", &parsed_rate) == 1)
2620 		lq_sta->dbg_fixed_rate = parsed_rate;
2621 	else
2622 		lq_sta->dbg_fixed_rate = 0;
2623 
2624 	lq_sta->active_legacy_rate = 0x0FFF;	/* 1 - 54 MBits, includes CCK */
2625 	lq_sta->active_siso_rate   = 0x1FD0;	/* 6 - 60 MBits, no 9, no CCK */
2626 	lq_sta->active_mimo2_rate  = 0x1FD0;	/* 6 - 60 MBits, no 9, no CCK */
2627 
2628 	IWL_DEBUG_RATE(priv, "sta_id %d rate 0x%X\n",
2629 		lq_sta->lq.sta_id, lq_sta->dbg_fixed_rate);
2630 
2631 	if (lq_sta->dbg_fixed_rate) {
2632 		iwl4965_rs_fill_link_cmd(NULL, lq_sta, lq_sta->dbg_fixed_rate);
2633 		iwl_legacy_send_lq_cmd(lq_sta->drv, ctx, &lq_sta->lq, CMD_ASYNC,
2634 				false);
2635 	}
2636 
2637 	return count;
2638 }
2639 
iwl4965_rs_sta_dbgfs_scale_table_read(struct file * file,char __user * user_buf,size_t count,loff_t * ppos)2640 static ssize_t iwl4965_rs_sta_dbgfs_scale_table_read(struct file *file,
2641 			char __user *user_buf, size_t count, loff_t *ppos)
2642 {
2643 	char *buff;
2644 	int desc = 0;
2645 	int i = 0;
2646 	int index = 0;
2647 	ssize_t ret;
2648 
2649 	struct iwl_lq_sta *lq_sta = file->private_data;
2650 	struct iwl_priv *priv;
2651 	struct iwl_scale_tbl_info *tbl = &(lq_sta->lq_info[lq_sta->active_tbl]);
2652 
2653 	priv = lq_sta->drv;
2654 	buff = kmalloc(1024, GFP_KERNEL);
2655 	if (!buff)
2656 		return -ENOMEM;
2657 
2658 	desc += sprintf(buff+desc, "sta_id %d\n", lq_sta->lq.sta_id);
2659 	desc += sprintf(buff+desc, "failed=%d success=%d rate=0%X\n",
2660 			lq_sta->total_failed, lq_sta->total_success,
2661 			lq_sta->active_legacy_rate);
2662 	desc += sprintf(buff+desc, "fixed rate 0x%X\n",
2663 			lq_sta->dbg_fixed_rate);
2664 	desc += sprintf(buff+desc, "valid_tx_ant %s%s%s\n",
2665 	    (priv->hw_params.valid_tx_ant & ANT_A) ? "ANT_A," : "",
2666 	    (priv->hw_params.valid_tx_ant & ANT_B) ? "ANT_B," : "",
2667 	    (priv->hw_params.valid_tx_ant & ANT_C) ? "ANT_C" : "");
2668 	desc += sprintf(buff+desc, "lq type %s\n",
2669 	   (is_legacy(tbl->lq_type)) ? "legacy" : "HT");
2670 	if (is_Ht(tbl->lq_type)) {
2671 		desc += sprintf(buff+desc, " %s",
2672 		   (is_siso(tbl->lq_type)) ? "SISO" : "MIMO2");
2673 		   desc += sprintf(buff+desc, " %s",
2674 		   (tbl->is_ht40) ? "40MHz" : "20MHz");
2675 		   desc += sprintf(buff+desc, " %s %s %s\n",
2676 			(tbl->is_SGI) ? "SGI" : "",
2677 		   (lq_sta->is_green) ? "GF enabled" : "",
2678 		   (lq_sta->is_agg) ? "AGG on" : "");
2679 	}
2680 	desc += sprintf(buff+desc, "last tx rate=0x%X\n",
2681 		lq_sta->last_rate_n_flags);
2682 	desc += sprintf(buff+desc, "general:"
2683 		"flags=0x%X mimo-d=%d s-ant0x%x d-ant=0x%x\n",
2684 		lq_sta->lq.general_params.flags,
2685 		lq_sta->lq.general_params.mimo_delimiter,
2686 		lq_sta->lq.general_params.single_stream_ant_msk,
2687 		lq_sta->lq.general_params.dual_stream_ant_msk);
2688 
2689 	desc += sprintf(buff+desc, "agg:"
2690 			"time_limit=%d dist_start_th=%d frame_cnt_limit=%d\n",
2691 			le16_to_cpu(lq_sta->lq.agg_params.agg_time_limit),
2692 			lq_sta->lq.agg_params.agg_dis_start_th,
2693 			lq_sta->lq.agg_params.agg_frame_cnt_limit);
2694 
2695 	desc += sprintf(buff+desc,
2696 			"Start idx [0]=0x%x [1]=0x%x [2]=0x%x [3]=0x%x\n",
2697 			lq_sta->lq.general_params.start_rate_index[0],
2698 			lq_sta->lq.general_params.start_rate_index[1],
2699 			lq_sta->lq.general_params.start_rate_index[2],
2700 			lq_sta->lq.general_params.start_rate_index[3]);
2701 
2702 	for (i = 0; i < LINK_QUAL_MAX_RETRY_NUM; i++) {
2703 		index = iwl4965_hwrate_to_plcp_idx(
2704 			le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags));
2705 		if (is_legacy(tbl->lq_type)) {
2706 			desc += sprintf(buff+desc, " rate[%d] 0x%X %smbps\n",
2707 			i,
2708 			le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2709 			iwl_rate_mcs[index].mbps);
2710 		} else {
2711 			desc += sprintf(buff+desc,
2712 			" rate[%d] 0x%X %smbps (%s)\n",
2713 			i,
2714 			le32_to_cpu(lq_sta->lq.rs_table[i].rate_n_flags),
2715 			iwl_rate_mcs[index].mbps, iwl_rate_mcs[index].mcs);
2716 		}
2717 	}
2718 
2719 	ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2720 	kfree(buff);
2721 	return ret;
2722 }
2723 
2724 static const struct file_operations rs_sta_dbgfs_scale_table_ops = {
2725 	.write = iwl4965_rs_sta_dbgfs_scale_table_write,
2726 	.read = iwl4965_rs_sta_dbgfs_scale_table_read,
2727 	.open = iwl4965_open_file_generic,
2728 	.llseek = default_llseek,
2729 };
iwl4965_rs_sta_dbgfs_stats_table_read(struct file * file,char __user * user_buf,size_t count,loff_t * ppos)2730 static ssize_t iwl4965_rs_sta_dbgfs_stats_table_read(struct file *file,
2731 			char __user *user_buf, size_t count, loff_t *ppos)
2732 {
2733 	char *buff;
2734 	int desc = 0;
2735 	int i, j;
2736 	ssize_t ret;
2737 
2738 	struct iwl_lq_sta *lq_sta = file->private_data;
2739 
2740 	buff = kmalloc(1024, GFP_KERNEL);
2741 	if (!buff)
2742 		return -ENOMEM;
2743 
2744 	for (i = 0; i < LQ_SIZE; i++) {
2745 		desc += sprintf(buff+desc,
2746 				"%s type=%d SGI=%d HT40=%d DUP=%d GF=%d\n"
2747 				"rate=0x%X\n",
2748 				lq_sta->active_tbl == i ? "*" : "x",
2749 				lq_sta->lq_info[i].lq_type,
2750 				lq_sta->lq_info[i].is_SGI,
2751 				lq_sta->lq_info[i].is_ht40,
2752 				lq_sta->lq_info[i].is_dup,
2753 				lq_sta->is_green,
2754 				lq_sta->lq_info[i].current_rate);
2755 		for (j = 0; j < IWL_RATE_COUNT; j++) {
2756 			desc += sprintf(buff+desc,
2757 				"counter=%d success=%d %%=%d\n",
2758 				lq_sta->lq_info[i].win[j].counter,
2759 				lq_sta->lq_info[i].win[j].success_counter,
2760 				lq_sta->lq_info[i].win[j].success_ratio);
2761 		}
2762 	}
2763 	ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2764 	kfree(buff);
2765 	return ret;
2766 }
2767 
2768 static const struct file_operations rs_sta_dbgfs_stats_table_ops = {
2769 	.read = iwl4965_rs_sta_dbgfs_stats_table_read,
2770 	.open = iwl4965_open_file_generic,
2771 	.llseek = default_llseek,
2772 };
2773 
iwl4965_rs_sta_dbgfs_rate_scale_data_read(struct file * file,char __user * user_buf,size_t count,loff_t * ppos)2774 static ssize_t iwl4965_rs_sta_dbgfs_rate_scale_data_read(struct file *file,
2775 			char __user *user_buf, size_t count, loff_t *ppos)
2776 {
2777 	char buff[120];
2778 	int desc = 0;
2779 	ssize_t ret;
2780 
2781 	struct iwl_lq_sta *lq_sta = file->private_data;
2782 	struct iwl_priv *priv;
2783 	struct iwl_scale_tbl_info *tbl = &lq_sta->lq_info[lq_sta->active_tbl];
2784 
2785 	priv = lq_sta->drv;
2786 
2787 	if (is_Ht(tbl->lq_type))
2788 		desc += sprintf(buff+desc,
2789 				"Bit Rate= %d Mb/s\n",
2790 				tbl->expected_tpt[lq_sta->last_txrate_idx]);
2791 	else
2792 		desc += sprintf(buff+desc,
2793 				"Bit Rate= %d Mb/s\n",
2794 				iwlegacy_rates[lq_sta->last_txrate_idx].ieee >> 1);
2795 
2796 	ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc);
2797 	return ret;
2798 }
2799 
2800 static const struct file_operations rs_sta_dbgfs_rate_scale_data_ops = {
2801 	.read = iwl4965_rs_sta_dbgfs_rate_scale_data_read,
2802 	.open = iwl4965_open_file_generic,
2803 	.llseek = default_llseek,
2804 };
2805 
iwl4965_rs_add_debugfs(void * priv,void * priv_sta,struct dentry * dir)2806 static void iwl4965_rs_add_debugfs(void *priv, void *priv_sta,
2807 					struct dentry *dir)
2808 {
2809 	struct iwl_lq_sta *lq_sta = priv_sta;
2810 	lq_sta->rs_sta_dbgfs_scale_table_file =
2811 		debugfs_create_file("rate_scale_table", S_IRUSR | S_IWUSR, dir,
2812 				lq_sta, &rs_sta_dbgfs_scale_table_ops);
2813 	lq_sta->rs_sta_dbgfs_stats_table_file =
2814 		debugfs_create_file("rate_stats_table", S_IRUSR, dir,
2815 			lq_sta, &rs_sta_dbgfs_stats_table_ops);
2816 	lq_sta->rs_sta_dbgfs_rate_scale_data_file =
2817 		debugfs_create_file("rate_scale_data", S_IRUSR, dir,
2818 			lq_sta, &rs_sta_dbgfs_rate_scale_data_ops);
2819 	lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file =
2820 		debugfs_create_u8("tx_agg_tid_enable", S_IRUSR | S_IWUSR, dir,
2821 		&lq_sta->tx_agg_tid_en);
2822 
2823 }
2824 
iwl4965_rs_remove_debugfs(void * priv,void * priv_sta)2825 static void iwl4965_rs_remove_debugfs(void *priv, void *priv_sta)
2826 {
2827 	struct iwl_lq_sta *lq_sta = priv_sta;
2828 	debugfs_remove(lq_sta->rs_sta_dbgfs_scale_table_file);
2829 	debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file);
2830 	debugfs_remove(lq_sta->rs_sta_dbgfs_rate_scale_data_file);
2831 	debugfs_remove(lq_sta->rs_sta_dbgfs_tx_agg_tid_en_file);
2832 }
2833 #endif
2834 
2835 /*
2836  * Initialization of rate scaling information is done by driver after
2837  * the station is added. Since mac80211 calls this function before a
2838  * station is added we ignore it.
2839  */
2840 static void
iwl4965_rs_rate_init_stub(void * priv_r,struct ieee80211_supported_band * sband,struct ieee80211_sta * sta,void * priv_sta)2841 iwl4965_rs_rate_init_stub(void *priv_r, struct ieee80211_supported_band *sband,
2842 			 struct ieee80211_sta *sta, void *priv_sta)
2843 {
2844 }
2845 static struct rate_control_ops rs_4965_ops = {
2846 	.module = NULL,
2847 	.name = IWL4965_RS_NAME,
2848 	.tx_status = iwl4965_rs_tx_status,
2849 	.get_rate = iwl4965_rs_get_rate,
2850 	.rate_init = iwl4965_rs_rate_init_stub,
2851 	.alloc = iwl4965_rs_alloc,
2852 	.free = iwl4965_rs_free,
2853 	.alloc_sta = iwl4965_rs_alloc_sta,
2854 	.free_sta = iwl4965_rs_free_sta,
2855 #ifdef CONFIG_MAC80211_DEBUGFS
2856 	.add_sta_debugfs = iwl4965_rs_add_debugfs,
2857 	.remove_sta_debugfs = iwl4965_rs_remove_debugfs,
2858 #endif
2859 };
2860 
iwl4965_rate_control_register(void)2861 int iwl4965_rate_control_register(void)
2862 {
2863 	pr_err("Registering 4965 rate control operations\n");
2864 	return ieee80211_rate_control_register(&rs_4965_ops);
2865 }
2866 
iwl4965_rate_control_unregister(void)2867 void iwl4965_rate_control_unregister(void)
2868 {
2869 	ieee80211_rate_control_unregister(&rs_4965_ops);
2870 }
2871