1/*
2 * Copyright (C) 2010 Bruno Randolf <br1@einfach.org>
3 *
4 * Permission to use, copy, modify, and/or distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 */
16
17#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18
19#include "ath5k.h"
20#include "reg.h"
21#include "debug.h"
22#include "ani.h"
23
24/**
25 * DOC: Basic ANI Operation
26 *
27 * Adaptive Noise Immunity (ANI) controls five noise immunity parameters
28 * depending on the amount of interference in the environment, increasing
29 * or reducing sensitivity as necessary.
30 *
31 * The parameters are:
32 *
33 *   - "noise immunity"
34 *
35 *   - "spur immunity"
36 *
37 *   - "firstep level"
38 *
39 *   - "OFDM weak signal detection"
40 *
41 *   - "CCK weak signal detection"
42 *
43 * Basically we look at the amount of ODFM and CCK timing errors we get and then
44 * raise or lower immunity accordingly by setting one or more of these
45 * parameters.
46 *
47 * Newer chipsets have PHY error counters in hardware which will generate a MIB
48 * interrupt when they overflow. Older hardware has too enable PHY error frames
49 * by setting a RX flag and then count every single PHY error. When a specified
50 * threshold of errors has been reached we will raise immunity.
51 * Also we regularly check the amount of errors and lower or raise immunity as
52 * necessary.
53 */
54
55
56/***********************\
57* ANI parameter control *
58\***********************/
59
60/**
61 * ath5k_ani_set_noise_immunity_level() - Set noise immunity level
62 * @ah: The &struct ath5k_hw
63 * @level: level between 0 and @ATH5K_ANI_MAX_NOISE_IMM_LVL
64 */
65void
66ath5k_ani_set_noise_immunity_level(struct ath5k_hw *ah, int level)
67{
68	/* TODO:
69	 * ANI documents suggest the following five levels to use, but the HAL
70	 * and ath9k use only the last two levels, making this
71	 * essentially an on/off option. There *may* be a reason for this (???),
72	 * so i stick with the HAL version for now...
73	 */
74#if 0
75	static const s8 lo[] = { -52, -56, -60, -64, -70 };
76	static const s8 hi[] = { -18, -18, -16, -14, -12 };
77	static const s8 sz[] = { -34, -41, -48, -55, -62 };
78	static const s8 fr[] = { -70, -72, -75, -78, -80 };
79#else
80	static const s8 lo[] = { -64, -70 };
81	static const s8 hi[] = { -14, -12 };
82	static const s8 sz[] = { -55, -62 };
83	static const s8 fr[] = { -78, -80 };
84#endif
85	if (level < 0 || level >= ARRAY_SIZE(sz)) {
86		ATH5K_ERR(ah, "noise immunity level %d out of range",
87			  level);
88		return;
89	}
90
91	AR5K_REG_WRITE_BITS(ah, AR5K_PHY_DESIRED_SIZE,
92				AR5K_PHY_DESIRED_SIZE_TOT, sz[level]);
93	AR5K_REG_WRITE_BITS(ah, AR5K_PHY_AGCCOARSE,
94				AR5K_PHY_AGCCOARSE_LO, lo[level]);
95	AR5K_REG_WRITE_BITS(ah, AR5K_PHY_AGCCOARSE,
96				AR5K_PHY_AGCCOARSE_HI, hi[level]);
97	AR5K_REG_WRITE_BITS(ah, AR5K_PHY_SIG,
98				AR5K_PHY_SIG_FIRPWR, fr[level]);
99
100	ah->ani_state.noise_imm_level = level;
101	ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI, "new level %d", level);
102}
103
104/**
105 * ath5k_ani_set_spur_immunity_level() - Set spur immunity level
106 * @ah: The &struct ath5k_hw
107 * @level: level between 0 and @max_spur_level (the maximum level is dependent
108 * on the chip revision).
109 */
110void
111ath5k_ani_set_spur_immunity_level(struct ath5k_hw *ah, int level)
112{
113	static const int val[] = { 2, 4, 6, 8, 10, 12, 14, 16 };
114
115	if (level < 0 || level >= ARRAY_SIZE(val) ||
116	    level > ah->ani_state.max_spur_level) {
117		ATH5K_ERR(ah, "spur immunity level %d out of range",
118			  level);
119		return;
120	}
121
122	AR5K_REG_WRITE_BITS(ah, AR5K_PHY_OFDM_SELFCORR,
123		AR5K_PHY_OFDM_SELFCORR_CYPWR_THR1, val[level]);
124
125	ah->ani_state.spur_level = level;
126	ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI, "new level %d", level);
127}
128
129/**
130 * ath5k_ani_set_firstep_level() - Set "firstep" level
131 * @ah: The &struct ath5k_hw
132 * @level: level between 0 and @ATH5K_ANI_MAX_FIRSTEP_LVL
133 */
134void
135ath5k_ani_set_firstep_level(struct ath5k_hw *ah, int level)
136{
137	static const int val[] = { 0, 4, 8 };
138
139	if (level < 0 || level >= ARRAY_SIZE(val)) {
140		ATH5K_ERR(ah, "firstep level %d out of range", level);
141		return;
142	}
143
144	AR5K_REG_WRITE_BITS(ah, AR5K_PHY_SIG,
145				AR5K_PHY_SIG_FIRSTEP, val[level]);
146
147	ah->ani_state.firstep_level = level;
148	ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI, "new level %d", level);
149}
150
151/**
152 * ath5k_ani_set_ofdm_weak_signal_detection() - Set OFDM weak signal detection
153 * @ah: The &struct ath5k_hw
154 * @on: turn on or off
155 */
156void
157ath5k_ani_set_ofdm_weak_signal_detection(struct ath5k_hw *ah, bool on)
158{
159	static const int m1l[] = { 127, 50 };
160	static const int m2l[] = { 127, 40 };
161	static const int m1[] = { 127, 0x4d };
162	static const int m2[] = { 127, 0x40 };
163	static const int m2cnt[] = { 31, 16 };
164	static const int m2lcnt[] = { 63, 48 };
165
166	AR5K_REG_WRITE_BITS(ah, AR5K_PHY_WEAK_OFDM_LOW_THR,
167				AR5K_PHY_WEAK_OFDM_LOW_THR_M1, m1l[on]);
168	AR5K_REG_WRITE_BITS(ah, AR5K_PHY_WEAK_OFDM_LOW_THR,
169				AR5K_PHY_WEAK_OFDM_LOW_THR_M2, m2l[on]);
170	AR5K_REG_WRITE_BITS(ah, AR5K_PHY_WEAK_OFDM_HIGH_THR,
171				AR5K_PHY_WEAK_OFDM_HIGH_THR_M1, m1[on]);
172	AR5K_REG_WRITE_BITS(ah, AR5K_PHY_WEAK_OFDM_HIGH_THR,
173				AR5K_PHY_WEAK_OFDM_HIGH_THR_M2, m2[on]);
174	AR5K_REG_WRITE_BITS(ah, AR5K_PHY_WEAK_OFDM_HIGH_THR,
175			AR5K_PHY_WEAK_OFDM_HIGH_THR_M2_COUNT, m2cnt[on]);
176	AR5K_REG_WRITE_BITS(ah, AR5K_PHY_WEAK_OFDM_LOW_THR,
177			AR5K_PHY_WEAK_OFDM_LOW_THR_M2_COUNT, m2lcnt[on]);
178
179	if (on)
180		AR5K_REG_ENABLE_BITS(ah, AR5K_PHY_WEAK_OFDM_LOW_THR,
181				AR5K_PHY_WEAK_OFDM_LOW_THR_SELFCOR_EN);
182	else
183		AR5K_REG_DISABLE_BITS(ah, AR5K_PHY_WEAK_OFDM_LOW_THR,
184				AR5K_PHY_WEAK_OFDM_LOW_THR_SELFCOR_EN);
185
186	ah->ani_state.ofdm_weak_sig = on;
187	ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI, "turned %s",
188			  on ? "on" : "off");
189}
190
191/**
192 * ath5k_ani_set_cck_weak_signal_detection() - Set CCK weak signal detection
193 * @ah: The &struct ath5k_hw
194 * @on: turn on or off
195 */
196void
197ath5k_ani_set_cck_weak_signal_detection(struct ath5k_hw *ah, bool on)
198{
199	static const int val[] = { 8, 6 };
200	AR5K_REG_WRITE_BITS(ah, AR5K_PHY_CCK_CROSSCORR,
201				AR5K_PHY_CCK_CROSSCORR_WEAK_SIG_THR, val[on]);
202	ah->ani_state.cck_weak_sig = on;
203	ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI, "turned %s",
204			  on ? "on" : "off");
205}
206
207
208/***************\
209* ANI algorithm *
210\***************/
211
212/**
213 * ath5k_ani_raise_immunity() - Increase noise immunity
214 * @ah: The &struct ath5k_hw
215 * @as: The &struct ath5k_ani_state
216 * @ofdm_trigger: If this is true we are called because of too many OFDM errors,
217 * the algorithm will tune more parameters then.
218 *
219 * Try to raise noise immunity (=decrease sensitivity) in several steps
220 * depending on the average RSSI of the beacons we received.
221 */
222static void
223ath5k_ani_raise_immunity(struct ath5k_hw *ah, struct ath5k_ani_state *as,
224			 bool ofdm_trigger)
225{
226	int rssi = ewma_beacon_rssi_read(&ah->ah_beacon_rssi_avg);
227
228	ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI, "raise immunity (%s)",
229		ofdm_trigger ? "ODFM" : "CCK");
230
231	/* first: raise noise immunity */
232	if (as->noise_imm_level < ATH5K_ANI_MAX_NOISE_IMM_LVL) {
233		ath5k_ani_set_noise_immunity_level(ah, as->noise_imm_level + 1);
234		return;
235	}
236
237	/* only OFDM: raise spur immunity level */
238	if (ofdm_trigger &&
239	    as->spur_level < ah->ani_state.max_spur_level) {
240		ath5k_ani_set_spur_immunity_level(ah, as->spur_level + 1);
241		return;
242	}
243
244	/* AP mode */
245	if (ah->opmode == NL80211_IFTYPE_AP) {
246		if (as->firstep_level < ATH5K_ANI_MAX_FIRSTEP_LVL)
247			ath5k_ani_set_firstep_level(ah, as->firstep_level + 1);
248		return;
249	}
250
251	/* STA and IBSS mode */
252
253	/* TODO: for IBSS mode it would be better to keep a beacon RSSI average
254	 * per each neighbour node and use the minimum of these, to make sure we
255	 * don't shut out a remote node by raising immunity too high. */
256
257	if (rssi > ATH5K_ANI_RSSI_THR_HIGH) {
258		ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI,
259				  "beacon RSSI high");
260		/* only OFDM: beacon RSSI is high, we can disable ODFM weak
261		 * signal detection */
262		if (ofdm_trigger && as->ofdm_weak_sig) {
263			ath5k_ani_set_ofdm_weak_signal_detection(ah, false);
264			ath5k_ani_set_spur_immunity_level(ah, 0);
265			return;
266		}
267		/* as a last resort or CCK: raise firstep level */
268		if (as->firstep_level < ATH5K_ANI_MAX_FIRSTEP_LVL) {
269			ath5k_ani_set_firstep_level(ah, as->firstep_level + 1);
270			return;
271		}
272	} else if (rssi > ATH5K_ANI_RSSI_THR_LOW) {
273		/* beacon RSSI in mid range, we need OFDM weak signal detect,
274		 * but can raise firstep level */
275		ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI,
276				  "beacon RSSI mid");
277		if (ofdm_trigger && !as->ofdm_weak_sig)
278			ath5k_ani_set_ofdm_weak_signal_detection(ah, true);
279		if (as->firstep_level < ATH5K_ANI_MAX_FIRSTEP_LVL)
280			ath5k_ani_set_firstep_level(ah, as->firstep_level + 1);
281		return;
282	} else if (ah->ah_current_channel->band == IEEE80211_BAND_2GHZ) {
283		/* beacon RSSI is low. in B/G mode turn of OFDM weak signal
284		 * detect and zero firstep level to maximize CCK sensitivity */
285		ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI,
286				  "beacon RSSI low, 2GHz");
287		if (ofdm_trigger && as->ofdm_weak_sig)
288			ath5k_ani_set_ofdm_weak_signal_detection(ah, false);
289		if (as->firstep_level > 0)
290			ath5k_ani_set_firstep_level(ah, 0);
291		return;
292	}
293
294	/* TODO: why not?:
295	if (as->cck_weak_sig == true) {
296		ath5k_ani_set_cck_weak_signal_detection(ah, false);
297	}
298	*/
299}
300
301/**
302 * ath5k_ani_lower_immunity() - Decrease noise immunity
303 * @ah: The &struct ath5k_hw
304 * @as: The &struct ath5k_ani_state
305 *
306 * Try to lower noise immunity (=increase sensitivity) in several steps
307 * depending on the average RSSI of the beacons we received.
308 */
309static void
310ath5k_ani_lower_immunity(struct ath5k_hw *ah, struct ath5k_ani_state *as)
311{
312	int rssi = ewma_beacon_rssi_read(&ah->ah_beacon_rssi_avg);
313
314	ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI, "lower immunity");
315
316	if (ah->opmode == NL80211_IFTYPE_AP) {
317		/* AP mode */
318		if (as->firstep_level > 0) {
319			ath5k_ani_set_firstep_level(ah, as->firstep_level - 1);
320			return;
321		}
322	} else {
323		/* STA and IBSS mode (see TODO above) */
324		if (rssi > ATH5K_ANI_RSSI_THR_HIGH) {
325			/* beacon signal is high, leave OFDM weak signal
326			 * detection off or it may oscillate
327			 * TODO: who said it's off??? */
328		} else if (rssi > ATH5K_ANI_RSSI_THR_LOW) {
329			/* beacon RSSI is mid-range: turn on ODFM weak signal
330			 * detection and next, lower firstep level */
331			if (!as->ofdm_weak_sig) {
332				ath5k_ani_set_ofdm_weak_signal_detection(ah,
333									 true);
334				return;
335			}
336			if (as->firstep_level > 0) {
337				ath5k_ani_set_firstep_level(ah,
338							as->firstep_level - 1);
339				return;
340			}
341		} else {
342			/* beacon signal is low: only reduce firstep level */
343			if (as->firstep_level > 0) {
344				ath5k_ani_set_firstep_level(ah,
345							as->firstep_level - 1);
346				return;
347			}
348		}
349	}
350
351	/* all modes */
352	if (as->spur_level > 0) {
353		ath5k_ani_set_spur_immunity_level(ah, as->spur_level - 1);
354		return;
355	}
356
357	/* finally, reduce noise immunity */
358	if (as->noise_imm_level > 0) {
359		ath5k_ani_set_noise_immunity_level(ah, as->noise_imm_level - 1);
360		return;
361	}
362}
363
364/**
365 * ath5k_hw_ani_get_listen_time() - Update counters and return listening time
366 * @ah: The &struct ath5k_hw
367 * @as: The &struct ath5k_ani_state
368 *
369 * Return an approximation of the time spent "listening" in milliseconds (ms)
370 * since the last call of this function.
371 * Save a snapshot of the counter values for debugging/statistics.
372 */
373static int
374ath5k_hw_ani_get_listen_time(struct ath5k_hw *ah, struct ath5k_ani_state *as)
375{
376	struct ath_common *common = ath5k_hw_common(ah);
377	int listen;
378
379	spin_lock_bh(&common->cc_lock);
380
381	ath_hw_cycle_counters_update(common);
382	memcpy(&as->last_cc, &common->cc_ani, sizeof(as->last_cc));
383
384	/* clears common->cc_ani */
385	listen = ath_hw_get_listen_time(common);
386
387	spin_unlock_bh(&common->cc_lock);
388
389	return listen;
390}
391
392/**
393 * ath5k_ani_save_and_clear_phy_errors() - Clear and save PHY error counters
394 * @ah: The &struct ath5k_hw
395 * @as: The &struct ath5k_ani_state
396 *
397 * Clear the PHY error counters as soon as possible, since this might be called
398 * from a MIB interrupt and we want to make sure we don't get interrupted again.
399 * Add the count of CCK and OFDM errors to our internal state, so it can be used
400 * by the algorithm later.
401 *
402 * Will be called from interrupt and tasklet context.
403 * Returns 0 if both counters are zero.
404 */
405static int
406ath5k_ani_save_and_clear_phy_errors(struct ath5k_hw *ah,
407				    struct ath5k_ani_state *as)
408{
409	unsigned int ofdm_err, cck_err;
410
411	if (!ah->ah_capabilities.cap_has_phyerr_counters)
412		return 0;
413
414	ofdm_err = ath5k_hw_reg_read(ah, AR5K_PHYERR_CNT1);
415	cck_err = ath5k_hw_reg_read(ah, AR5K_PHYERR_CNT2);
416
417	/* reset counters first, we might be in a hurry (interrupt) */
418	ath5k_hw_reg_write(ah, ATH5K_PHYERR_CNT_MAX - ATH5K_ANI_OFDM_TRIG_HIGH,
419			   AR5K_PHYERR_CNT1);
420	ath5k_hw_reg_write(ah, ATH5K_PHYERR_CNT_MAX - ATH5K_ANI_CCK_TRIG_HIGH,
421			   AR5K_PHYERR_CNT2);
422
423	ofdm_err = ATH5K_ANI_OFDM_TRIG_HIGH - (ATH5K_PHYERR_CNT_MAX - ofdm_err);
424	cck_err = ATH5K_ANI_CCK_TRIG_HIGH - (ATH5K_PHYERR_CNT_MAX - cck_err);
425
426	/* sometimes both can be zero, especially when there is a superfluous
427	 * second interrupt. detect that here and return an error. */
428	if (ofdm_err <= 0 && cck_err <= 0)
429		return 0;
430
431	/* avoid negative values should one of the registers overflow */
432	if (ofdm_err > 0) {
433		as->ofdm_errors += ofdm_err;
434		as->sum_ofdm_errors += ofdm_err;
435	}
436	if (cck_err > 0) {
437		as->cck_errors += cck_err;
438		as->sum_cck_errors += cck_err;
439	}
440	return 1;
441}
442
443/**
444 * ath5k_ani_period_restart() - Restart ANI period
445 * @as: The &struct ath5k_ani_state
446 *
447 * Just reset counters, so they are clear for the next "ani period".
448 */
449static void
450ath5k_ani_period_restart(struct ath5k_ani_state *as)
451{
452	/* keep last values for debugging */
453	as->last_ofdm_errors = as->ofdm_errors;
454	as->last_cck_errors = as->cck_errors;
455	as->last_listen = as->listen_time;
456
457	as->ofdm_errors = 0;
458	as->cck_errors = 0;
459	as->listen_time = 0;
460}
461
462/**
463 * ath5k_ani_calibration() - The main ANI calibration function
464 * @ah: The &struct ath5k_hw
465 *
466 * We count OFDM and CCK errors relative to the time where we did not send or
467 * receive ("listen" time) and raise or lower immunity accordingly.
468 * This is called regularly (every second) from the calibration timer, but also
469 * when an error threshold has been reached.
470 *
471 * In order to synchronize access from different contexts, this should be
472 * called only indirectly by scheduling the ANI tasklet!
473 */
474void
475ath5k_ani_calibration(struct ath5k_hw *ah)
476{
477	struct ath5k_ani_state *as = &ah->ani_state;
478	int listen, ofdm_high, ofdm_low, cck_high, cck_low;
479
480	/* get listen time since last call and add it to the counter because we
481	 * might not have restarted the "ani period" last time.
482	 * always do this to calculate the busy time also in manual mode */
483	listen = ath5k_hw_ani_get_listen_time(ah, as);
484	as->listen_time += listen;
485
486	if (as->ani_mode != ATH5K_ANI_MODE_AUTO)
487		return;
488
489	ath5k_ani_save_and_clear_phy_errors(ah, as);
490
491	ofdm_high = as->listen_time * ATH5K_ANI_OFDM_TRIG_HIGH / 1000;
492	cck_high = as->listen_time * ATH5K_ANI_CCK_TRIG_HIGH / 1000;
493	ofdm_low = as->listen_time * ATH5K_ANI_OFDM_TRIG_LOW / 1000;
494	cck_low = as->listen_time * ATH5K_ANI_CCK_TRIG_LOW / 1000;
495
496	ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI,
497		"listen %d (now %d)", as->listen_time, listen);
498	ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI,
499		"check high ofdm %d/%d cck %d/%d",
500		as->ofdm_errors, ofdm_high, as->cck_errors, cck_high);
501
502	if (as->ofdm_errors > ofdm_high || as->cck_errors > cck_high) {
503		/* too many PHY errors - we have to raise immunity */
504		bool ofdm_flag = as->ofdm_errors > ofdm_high ? true : false;
505		ath5k_ani_raise_immunity(ah, as, ofdm_flag);
506		ath5k_ani_period_restart(as);
507
508	} else if (as->listen_time > 5 * ATH5K_ANI_LISTEN_PERIOD) {
509		/* If more than 5 (TODO: why 5?) periods have passed and we got
510		 * relatively little errors we can try to lower immunity */
511		ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI,
512			"check low ofdm %d/%d cck %d/%d",
513			as->ofdm_errors, ofdm_low, as->cck_errors, cck_low);
514
515		if (as->ofdm_errors <= ofdm_low && as->cck_errors <= cck_low)
516			ath5k_ani_lower_immunity(ah, as);
517
518		ath5k_ani_period_restart(as);
519	}
520}
521
522
523/*******************\
524* Interrupt handler *
525\*******************/
526
527/**
528 * ath5k_ani_mib_intr() - Interrupt handler for ANI MIB counters
529 * @ah: The &struct ath5k_hw
530 *
531 * Just read & reset the registers quickly, so they don't generate more
532 * interrupts, save the counters and schedule the tasklet to decide whether
533 * to raise immunity or not.
534 *
535 * We just need to handle PHY error counters, ath5k_hw_update_mib_counters()
536 * should take care of all "normal" MIB interrupts.
537 */
538void
539ath5k_ani_mib_intr(struct ath5k_hw *ah)
540{
541	struct ath5k_ani_state *as = &ah->ani_state;
542
543	/* nothing to do here if HW does not have PHY error counters - they
544	 * can't be the reason for the MIB interrupt then */
545	if (!ah->ah_capabilities.cap_has_phyerr_counters)
546		return;
547
548	/* not in use but clear anyways */
549	ath5k_hw_reg_write(ah, 0, AR5K_OFDM_FIL_CNT);
550	ath5k_hw_reg_write(ah, 0, AR5K_CCK_FIL_CNT);
551
552	if (ah->ani_state.ani_mode != ATH5K_ANI_MODE_AUTO)
553		return;
554
555	/* If one of the errors triggered, we can get a superfluous second
556	 * interrupt, even though we have already reset the register. The
557	 * function detects that so we can return early. */
558	if (ath5k_ani_save_and_clear_phy_errors(ah, as) == 0)
559		return;
560
561	if (as->ofdm_errors > ATH5K_ANI_OFDM_TRIG_HIGH ||
562	    as->cck_errors > ATH5K_ANI_CCK_TRIG_HIGH)
563		tasklet_schedule(&ah->ani_tasklet);
564}
565
566/**
567 * ath5k_ani_phy_error_report - Used by older HW to report PHY errors
568 *
569 * @ah: The &struct ath5k_hw
570 * @phyerr: One of enum ath5k_phy_error_code
571 *
572 * This is used by hardware without PHY error counters to report PHY errors
573 * on a frame-by-frame basis, instead of the interrupt.
574 */
575void
576ath5k_ani_phy_error_report(struct ath5k_hw *ah,
577			   enum ath5k_phy_error_code phyerr)
578{
579	struct ath5k_ani_state *as = &ah->ani_state;
580
581	if (phyerr == AR5K_RX_PHY_ERROR_OFDM_TIMING) {
582		as->ofdm_errors++;
583		if (as->ofdm_errors > ATH5K_ANI_OFDM_TRIG_HIGH)
584			tasklet_schedule(&ah->ani_tasklet);
585	} else if (phyerr == AR5K_RX_PHY_ERROR_CCK_TIMING) {
586		as->cck_errors++;
587		if (as->cck_errors > ATH5K_ANI_CCK_TRIG_HIGH)
588			tasklet_schedule(&ah->ani_tasklet);
589	}
590}
591
592
593/****************\
594* Initialization *
595\****************/
596
597/**
598 * ath5k_enable_phy_err_counters() - Enable PHY error counters
599 * @ah: The &struct ath5k_hw
600 *
601 * Enable PHY error counters for OFDM and CCK timing errors.
602 */
603static void
604ath5k_enable_phy_err_counters(struct ath5k_hw *ah)
605{
606	ath5k_hw_reg_write(ah, ATH5K_PHYERR_CNT_MAX - ATH5K_ANI_OFDM_TRIG_HIGH,
607			   AR5K_PHYERR_CNT1);
608	ath5k_hw_reg_write(ah, ATH5K_PHYERR_CNT_MAX - ATH5K_ANI_CCK_TRIG_HIGH,
609			   AR5K_PHYERR_CNT2);
610	ath5k_hw_reg_write(ah, AR5K_PHY_ERR_FIL_OFDM, AR5K_PHYERR_CNT1_MASK);
611	ath5k_hw_reg_write(ah, AR5K_PHY_ERR_FIL_CCK, AR5K_PHYERR_CNT2_MASK);
612
613	/* not in use */
614	ath5k_hw_reg_write(ah, 0, AR5K_OFDM_FIL_CNT);
615	ath5k_hw_reg_write(ah, 0, AR5K_CCK_FIL_CNT);
616}
617
618/**
619 * ath5k_disable_phy_err_counters() - Disable PHY error counters
620 * @ah: The &struct ath5k_hw
621 *
622 * Disable PHY error counters for OFDM and CCK timing errors.
623 */
624static void
625ath5k_disable_phy_err_counters(struct ath5k_hw *ah)
626{
627	ath5k_hw_reg_write(ah, 0, AR5K_PHYERR_CNT1);
628	ath5k_hw_reg_write(ah, 0, AR5K_PHYERR_CNT2);
629	ath5k_hw_reg_write(ah, 0, AR5K_PHYERR_CNT1_MASK);
630	ath5k_hw_reg_write(ah, 0, AR5K_PHYERR_CNT2_MASK);
631
632	/* not in use */
633	ath5k_hw_reg_write(ah, 0, AR5K_OFDM_FIL_CNT);
634	ath5k_hw_reg_write(ah, 0, AR5K_CCK_FIL_CNT);
635}
636
637/**
638 * ath5k_ani_init() - Initialize ANI
639 * @ah: The &struct ath5k_hw
640 * @mode: One of enum ath5k_ani_mode
641 *
642 * Initialize ANI according to mode.
643 */
644void
645ath5k_ani_init(struct ath5k_hw *ah, enum ath5k_ani_mode mode)
646{
647	/* ANI is only possible on 5212 and newer */
648	if (ah->ah_version < AR5K_AR5212)
649		return;
650
651	if (mode < ATH5K_ANI_MODE_OFF || mode > ATH5K_ANI_MODE_AUTO) {
652		ATH5K_ERR(ah, "ANI mode %d out of range", mode);
653		return;
654	}
655
656	/* clear old state information */
657	memset(&ah->ani_state, 0, sizeof(ah->ani_state));
658
659	/* older hardware has more spur levels than newer */
660	if (ah->ah_mac_srev < AR5K_SREV_AR2414)
661		ah->ani_state.max_spur_level = 7;
662	else
663		ah->ani_state.max_spur_level = 2;
664
665	/* initial values for our ani parameters */
666	if (mode == ATH5K_ANI_MODE_OFF) {
667		ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI, "ANI off\n");
668	} else if (mode == ATH5K_ANI_MODE_MANUAL_LOW) {
669		ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI,
670			"ANI manual low -> high sensitivity\n");
671		ath5k_ani_set_noise_immunity_level(ah, 0);
672		ath5k_ani_set_spur_immunity_level(ah, 0);
673		ath5k_ani_set_firstep_level(ah, 0);
674		ath5k_ani_set_ofdm_weak_signal_detection(ah, true);
675		ath5k_ani_set_cck_weak_signal_detection(ah, true);
676	} else if (mode == ATH5K_ANI_MODE_MANUAL_HIGH) {
677		ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI,
678			"ANI manual high -> low sensitivity\n");
679		ath5k_ani_set_noise_immunity_level(ah,
680					ATH5K_ANI_MAX_NOISE_IMM_LVL);
681		ath5k_ani_set_spur_immunity_level(ah,
682					ah->ani_state.max_spur_level);
683		ath5k_ani_set_firstep_level(ah, ATH5K_ANI_MAX_FIRSTEP_LVL);
684		ath5k_ani_set_ofdm_weak_signal_detection(ah, false);
685		ath5k_ani_set_cck_weak_signal_detection(ah, false);
686	} else if (mode == ATH5K_ANI_MODE_AUTO) {
687		ATH5K_DBG_UNLIMIT(ah, ATH5K_DEBUG_ANI, "ANI auto\n");
688		ath5k_ani_set_noise_immunity_level(ah, 0);
689		ath5k_ani_set_spur_immunity_level(ah, 0);
690		ath5k_ani_set_firstep_level(ah, 0);
691		ath5k_ani_set_ofdm_weak_signal_detection(ah, true);
692		ath5k_ani_set_cck_weak_signal_detection(ah, false);
693	}
694
695	/* newer hardware has PHY error counter registers which we can use to
696	 * get OFDM and CCK error counts. older hardware has to set rxfilter and
697	 * report every single PHY error by calling ath5k_ani_phy_error_report()
698	 */
699	if (mode == ATH5K_ANI_MODE_AUTO) {
700		if (ah->ah_capabilities.cap_has_phyerr_counters)
701			ath5k_enable_phy_err_counters(ah);
702		else
703			ath5k_hw_set_rx_filter(ah, ath5k_hw_get_rx_filter(ah) |
704						   AR5K_RX_FILTER_PHYERR);
705	} else {
706		if (ah->ah_capabilities.cap_has_phyerr_counters)
707			ath5k_disable_phy_err_counters(ah);
708		else
709			ath5k_hw_set_rx_filter(ah, ath5k_hw_get_rx_filter(ah) &
710						   ~AR5K_RX_FILTER_PHYERR);
711	}
712
713	ah->ani_state.ani_mode = mode;
714}
715
716
717/**************\
718* Debug output *
719\**************/
720
721#ifdef CONFIG_ATH5K_DEBUG
722
723/**
724 * ath5k_ani_print_counters() - Print ANI counters
725 * @ah: The &struct ath5k_hw
726 *
727 * Used for debugging ANI
728 */
729void
730ath5k_ani_print_counters(struct ath5k_hw *ah)
731{
732	/* clears too */
733	pr_notice("ACK fail\t%d\n", ath5k_hw_reg_read(ah, AR5K_ACK_FAIL));
734	pr_notice("RTS fail\t%d\n", ath5k_hw_reg_read(ah, AR5K_RTS_FAIL));
735	pr_notice("RTS success\t%d\n", ath5k_hw_reg_read(ah, AR5K_RTS_OK));
736	pr_notice("FCS error\t%d\n", ath5k_hw_reg_read(ah, AR5K_FCS_FAIL));
737
738	/* no clear */
739	pr_notice("tx\t%d\n", ath5k_hw_reg_read(ah, AR5K_PROFCNT_TX));
740	pr_notice("rx\t%d\n", ath5k_hw_reg_read(ah, AR5K_PROFCNT_RX));
741	pr_notice("busy\t%d\n", ath5k_hw_reg_read(ah, AR5K_PROFCNT_RXCLR));
742	pr_notice("cycles\t%d\n", ath5k_hw_reg_read(ah, AR5K_PROFCNT_CYCLE));
743
744	pr_notice("AR5K_PHYERR_CNT1\t%d\n",
745		  ath5k_hw_reg_read(ah, AR5K_PHYERR_CNT1));
746	pr_notice("AR5K_PHYERR_CNT2\t%d\n",
747		  ath5k_hw_reg_read(ah, AR5K_PHYERR_CNT2));
748	pr_notice("AR5K_OFDM_FIL_CNT\t%d\n",
749		  ath5k_hw_reg_read(ah, AR5K_OFDM_FIL_CNT));
750	pr_notice("AR5K_CCK_FIL_CNT\t%d\n",
751		  ath5k_hw_reg_read(ah, AR5K_CCK_FIL_CNT));
752}
753
754#endif
755