1 /* 2 * Copyright (c) 2008-2011 Atheros Communications Inc. 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 #include "hw.h" 18 #include "hw-ops.h" 19 #include <linux/export.h> 20 21 /* Common calibration code */ 22 23 24 static int16_t ath9k_hw_get_nf_hist_mid(int16_t *nfCalBuffer) 25 { 26 int16_t nfval; 27 int16_t sort[ATH9K_NF_CAL_HIST_MAX]; 28 int i, j; 29 30 for (i = 0; i < ATH9K_NF_CAL_HIST_MAX; i++) 31 sort[i] = nfCalBuffer[i]; 32 33 for (i = 0; i < ATH9K_NF_CAL_HIST_MAX - 1; i++) { 34 for (j = 1; j < ATH9K_NF_CAL_HIST_MAX - i; j++) { 35 if (sort[j] > sort[j - 1]) { 36 nfval = sort[j]; 37 sort[j] = sort[j - 1]; 38 sort[j - 1] = nfval; 39 } 40 } 41 } 42 nfval = sort[(ATH9K_NF_CAL_HIST_MAX - 1) >> 1]; 43 44 return nfval; 45 } 46 47 static struct ath_nf_limits *ath9k_hw_get_nf_limits(struct ath_hw *ah, 48 struct ath9k_channel *chan) 49 { 50 struct ath_nf_limits *limit; 51 52 if (!chan || IS_CHAN_2GHZ(chan)) 53 limit = &ah->nf_2g; 54 else 55 limit = &ah->nf_5g; 56 57 return limit; 58 } 59 60 static s16 ath9k_hw_get_default_nf(struct ath_hw *ah, 61 struct ath9k_channel *chan, 62 int chain) 63 { 64 s16 calib_nf = ath9k_hw_get_nf_limits(ah, chan)->cal[chain]; 65 66 if (calib_nf) 67 return calib_nf; 68 else 69 return ath9k_hw_get_nf_limits(ah, chan)->nominal; 70 } 71 72 s16 ath9k_hw_getchan_noise(struct ath_hw *ah, struct ath9k_channel *chan, 73 s16 nf) 74 { 75 s8 noise = ATH_DEFAULT_NOISE_FLOOR; 76 77 if (nf) { 78 s8 delta = nf - ATH9K_NF_CAL_NOISE_THRESH - 79 ath9k_hw_get_default_nf(ah, chan, 0); 80 if (delta > 0) 81 noise += delta; 82 } 83 return noise; 84 } 85 EXPORT_SYMBOL(ath9k_hw_getchan_noise); 86 87 static void ath9k_hw_update_nfcal_hist_buffer(struct ath_hw *ah, 88 struct ath9k_hw_cal_data *cal, 89 int16_t *nfarray) 90 { 91 struct ath_common *common = ath9k_hw_common(ah); 92 struct ath_nf_limits *limit; 93 struct ath9k_nfcal_hist *h; 94 bool high_nf_mid = false; 95 u8 chainmask = (ah->rxchainmask << 3) | ah->rxchainmask; 96 int i; 97 98 h = cal->nfCalHist; 99 limit = ath9k_hw_get_nf_limits(ah, ah->curchan); 100 101 for (i = 0; i < NUM_NF_READINGS; i++) { 102 if (!(chainmask & (1 << i)) || 103 ((i >= AR5416_MAX_CHAINS) && !IS_CHAN_HT40(ah->curchan))) 104 continue; 105 106 h[i].nfCalBuffer[h[i].currIndex] = nfarray[i]; 107 108 if (++h[i].currIndex >= ATH9K_NF_CAL_HIST_MAX) 109 h[i].currIndex = 0; 110 111 if (h[i].invalidNFcount > 0) { 112 h[i].invalidNFcount--; 113 h[i].privNF = nfarray[i]; 114 } else { 115 h[i].privNF = 116 ath9k_hw_get_nf_hist_mid(h[i].nfCalBuffer); 117 } 118 119 if (!h[i].privNF) 120 continue; 121 122 if (h[i].privNF > limit->max) { 123 high_nf_mid = true; 124 125 ath_dbg(common, CALIBRATE, 126 "NFmid[%d] (%d) > MAX (%d), %s\n", 127 i, h[i].privNF, limit->max, 128 (test_bit(NFCAL_INTF, &cal->cal_flags) ? 129 "not corrected (due to interference)" : 130 "correcting to MAX")); 131 132 /* 133 * Normally we limit the average noise floor by the 134 * hardware specific maximum here. However if we have 135 * encountered stuck beacons because of interference, 136 * we bypass this limit here in order to better deal 137 * with our environment. 138 */ 139 if (!test_bit(NFCAL_INTF, &cal->cal_flags)) 140 h[i].privNF = limit->max; 141 } 142 } 143 144 /* 145 * If the noise floor seems normal for all chains, assume that 146 * there is no significant interference in the environment anymore. 147 * Re-enable the enforcement of the NF maximum again. 148 */ 149 if (!high_nf_mid) 150 clear_bit(NFCAL_INTF, &cal->cal_flags); 151 } 152 153 static bool ath9k_hw_get_nf_thresh(struct ath_hw *ah, 154 enum nl80211_band band, 155 int16_t *nft) 156 { 157 switch (band) { 158 case NL80211_BAND_5GHZ: 159 *nft = (int8_t)ah->eep_ops->get_eeprom(ah, EEP_NFTHRESH_5); 160 break; 161 case NL80211_BAND_2GHZ: 162 *nft = (int8_t)ah->eep_ops->get_eeprom(ah, EEP_NFTHRESH_2); 163 break; 164 default: 165 BUG_ON(1); 166 return false; 167 } 168 169 return true; 170 } 171 172 void ath9k_hw_reset_calibration(struct ath_hw *ah, 173 struct ath9k_cal_list *currCal) 174 { 175 int i; 176 177 ath9k_hw_setup_calibration(ah, currCal); 178 179 ah->cal_start_time = jiffies; 180 currCal->calState = CAL_RUNNING; 181 182 for (i = 0; i < AR5416_MAX_CHAINS; i++) { 183 ah->meas0.sign[i] = 0; 184 ah->meas1.sign[i] = 0; 185 ah->meas2.sign[i] = 0; 186 ah->meas3.sign[i] = 0; 187 } 188 189 ah->cal_samples = 0; 190 } 191 192 /* This is done for the currently configured channel */ 193 bool ath9k_hw_reset_calvalid(struct ath_hw *ah) 194 { 195 struct ath_common *common = ath9k_hw_common(ah); 196 struct ath9k_cal_list *currCal = ah->cal_list_curr; 197 198 if (!ah->caldata) 199 return true; 200 201 if (!AR_SREV_9100(ah) && !AR_SREV_9160_10_OR_LATER(ah)) 202 return true; 203 204 if (currCal == NULL) 205 return true; 206 207 if (currCal->calState != CAL_DONE) { 208 ath_dbg(common, CALIBRATE, "Calibration state incorrect, %d\n", 209 currCal->calState); 210 return true; 211 } 212 213 currCal = ah->cal_list; 214 do { 215 ath_dbg(common, CALIBRATE, "Resetting Cal %d state for channel %u\n", 216 currCal->calData->calType, 217 ah->curchan->chan->center_freq); 218 219 ah->caldata->CalValid &= ~currCal->calData->calType; 220 currCal->calState = CAL_WAITING; 221 222 currCal = currCal->calNext; 223 } while (currCal != ah->cal_list); 224 225 return false; 226 } 227 EXPORT_SYMBOL(ath9k_hw_reset_calvalid); 228 229 void ath9k_hw_start_nfcal(struct ath_hw *ah, bool update) 230 { 231 if (ah->caldata) 232 set_bit(NFCAL_PENDING, &ah->caldata->cal_flags); 233 234 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL, 235 AR_PHY_AGC_CONTROL_ENABLE_NF); 236 237 if (update) 238 REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL, 239 AR_PHY_AGC_CONTROL_NO_UPDATE_NF); 240 else 241 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL, 242 AR_PHY_AGC_CONTROL_NO_UPDATE_NF); 243 244 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL, AR_PHY_AGC_CONTROL_NF); 245 } 246 247 int ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan) 248 { 249 struct ath9k_nfcal_hist *h = NULL; 250 unsigned i, j; 251 u8 chainmask = (ah->rxchainmask << 3) | ah->rxchainmask; 252 struct ath_common *common = ath9k_hw_common(ah); 253 s16 default_nf = ath9k_hw_get_nf_limits(ah, chan)->nominal; 254 u32 bb_agc_ctl = REG_READ(ah, AR_PHY_AGC_CONTROL); 255 256 if (ah->caldata) 257 h = ah->caldata->nfCalHist; 258 259 ENABLE_REG_RMW_BUFFER(ah); 260 for (i = 0; i < NUM_NF_READINGS; i++) { 261 if (chainmask & (1 << i)) { 262 s16 nfval; 263 264 if ((i >= AR5416_MAX_CHAINS) && !IS_CHAN_HT40(chan)) 265 continue; 266 267 if (ah->nf_override) 268 nfval = ah->nf_override; 269 else if (h) 270 nfval = h[i].privNF; 271 else { 272 /* Try to get calibrated noise floor value */ 273 nfval = 274 ath9k_hw_get_nf_limits(ah, chan)->cal[i]; 275 if (nfval > -60 || nfval < -127) 276 nfval = default_nf; 277 } 278 279 REG_RMW(ah, ah->nf_regs[i], 280 (((u32) nfval << 1) & 0x1ff), 0x1ff); 281 } 282 } 283 284 /* 285 * stop NF cal if ongoing to ensure NF load completes immediately 286 * (or after end rx/tx frame if ongoing) 287 */ 288 if (bb_agc_ctl & AR_PHY_AGC_CONTROL_NF) { 289 REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL, AR_PHY_AGC_CONTROL_NF); 290 REG_RMW_BUFFER_FLUSH(ah); 291 ENABLE_REG_RMW_BUFFER(ah); 292 } 293 294 /* 295 * Load software filtered NF value into baseband internal minCCApwr 296 * variable. 297 */ 298 REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL, 299 AR_PHY_AGC_CONTROL_ENABLE_NF); 300 REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL, 301 AR_PHY_AGC_CONTROL_NO_UPDATE_NF); 302 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL, AR_PHY_AGC_CONTROL_NF); 303 REG_RMW_BUFFER_FLUSH(ah); 304 305 /* 306 * Wait for load to complete, should be fast, a few 10s of us. 307 * The max delay was changed from an original 250us to 22.2 msec. 308 * This would increase timeout to the longest possible frame 309 * (11n max length 22.1 msec) 310 */ 311 for (j = 0; j < 22200; j++) { 312 if ((REG_READ(ah, AR_PHY_AGC_CONTROL) & 313 AR_PHY_AGC_CONTROL_NF) == 0) 314 break; 315 udelay(10); 316 } 317 318 /* 319 * Restart NF so it can continue. 320 */ 321 if (bb_agc_ctl & AR_PHY_AGC_CONTROL_NF) { 322 ENABLE_REG_RMW_BUFFER(ah); 323 if (bb_agc_ctl & AR_PHY_AGC_CONTROL_ENABLE_NF) 324 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL, 325 AR_PHY_AGC_CONTROL_ENABLE_NF); 326 if (bb_agc_ctl & AR_PHY_AGC_CONTROL_NO_UPDATE_NF) 327 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL, 328 AR_PHY_AGC_CONTROL_NO_UPDATE_NF); 329 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL, AR_PHY_AGC_CONTROL_NF); 330 REG_RMW_BUFFER_FLUSH(ah); 331 } 332 333 /* 334 * We timed out waiting for the noisefloor to load, probably due to an 335 * in-progress rx. Simply return here and allow the load plenty of time 336 * to complete before the next calibration interval. We need to avoid 337 * trying to load -50 (which happens below) while the previous load is 338 * still in progress as this can cause rx deafness. Instead by returning 339 * here, the baseband nf cal will just be capped by our present 340 * noisefloor until the next calibration timer. 341 */ 342 if (j == 22200) { 343 ath_dbg(common, ANY, 344 "Timeout while waiting for nf to load: AR_PHY_AGC_CONTROL=0x%x\n", 345 REG_READ(ah, AR_PHY_AGC_CONTROL)); 346 return -ETIMEDOUT; 347 } 348 349 /* 350 * Restore maxCCAPower register parameter again so that we're not capped 351 * by the median we just loaded. This will be initial (and max) value 352 * of next noise floor calibration the baseband does. 353 */ 354 ENABLE_REG_RMW_BUFFER(ah); 355 for (i = 0; i < NUM_NF_READINGS; i++) { 356 if (chainmask & (1 << i)) { 357 if ((i >= AR5416_MAX_CHAINS) && !IS_CHAN_HT40(chan)) 358 continue; 359 360 REG_RMW(ah, ah->nf_regs[i], 361 (((u32) (-50) << 1) & 0x1ff), 0x1ff); 362 } 363 } 364 REG_RMW_BUFFER_FLUSH(ah); 365 366 return 0; 367 } 368 EXPORT_SYMBOL(ath9k_hw_loadnf); 369 370 371 static void ath9k_hw_nf_sanitize(struct ath_hw *ah, s16 *nf) 372 { 373 struct ath_common *common = ath9k_hw_common(ah); 374 struct ath_nf_limits *limit; 375 int i; 376 377 if (IS_CHAN_2GHZ(ah->curchan)) 378 limit = &ah->nf_2g; 379 else 380 limit = &ah->nf_5g; 381 382 for (i = 0; i < NUM_NF_READINGS; i++) { 383 if (!nf[i]) 384 continue; 385 386 ath_dbg(common, CALIBRATE, 387 "NF calibrated [%s] [chain %d] is %d\n", 388 (i >= 3 ? "ext" : "ctl"), i % 3, nf[i]); 389 390 if (nf[i] > limit->max) { 391 ath_dbg(common, CALIBRATE, 392 "NF[%d] (%d) > MAX (%d), correcting to MAX\n", 393 i, nf[i], limit->max); 394 nf[i] = limit->max; 395 } else if (nf[i] < limit->min) { 396 ath_dbg(common, CALIBRATE, 397 "NF[%d] (%d) < MIN (%d), correcting to NOM\n", 398 i, nf[i], limit->min); 399 nf[i] = limit->nominal; 400 } 401 } 402 } 403 404 bool ath9k_hw_getnf(struct ath_hw *ah, struct ath9k_channel *chan) 405 { 406 struct ath_common *common = ath9k_hw_common(ah); 407 int16_t nf, nfThresh; 408 int16_t nfarray[NUM_NF_READINGS] = { 0 }; 409 struct ath9k_nfcal_hist *h; 410 struct ieee80211_channel *c = chan->chan; 411 struct ath9k_hw_cal_data *caldata = ah->caldata; 412 413 if (REG_READ(ah, AR_PHY_AGC_CONTROL) & AR_PHY_AGC_CONTROL_NF) { 414 ath_dbg(common, CALIBRATE, 415 "NF did not complete in calibration window\n"); 416 return false; 417 } 418 419 ath9k_hw_do_getnf(ah, nfarray); 420 ath9k_hw_nf_sanitize(ah, nfarray); 421 nf = nfarray[0]; 422 if (ath9k_hw_get_nf_thresh(ah, c->band, &nfThresh) 423 && nf > nfThresh) { 424 ath_dbg(common, CALIBRATE, 425 "noise floor failed detected; detected %d, threshold %d\n", 426 nf, nfThresh); 427 } 428 429 if (!caldata) { 430 chan->noisefloor = nf; 431 return false; 432 } 433 434 h = caldata->nfCalHist; 435 clear_bit(NFCAL_PENDING, &caldata->cal_flags); 436 ath9k_hw_update_nfcal_hist_buffer(ah, caldata, nfarray); 437 chan->noisefloor = h[0].privNF; 438 ah->noise = ath9k_hw_getchan_noise(ah, chan, chan->noisefloor); 439 return true; 440 } 441 EXPORT_SYMBOL(ath9k_hw_getnf); 442 443 void ath9k_init_nfcal_hist_buffer(struct ath_hw *ah, 444 struct ath9k_channel *chan) 445 { 446 struct ath9k_nfcal_hist *h; 447 int i, j, k = 0; 448 449 ah->caldata->channel = chan->channel; 450 ah->caldata->channelFlags = chan->channelFlags; 451 h = ah->caldata->nfCalHist; 452 for (i = 0; i < NUM_NF_READINGS; i++) { 453 h[i].currIndex = 0; 454 h[i].privNF = ath9k_hw_get_default_nf(ah, chan, k); 455 h[i].invalidNFcount = AR_PHY_CCA_FILTERWINDOW_LENGTH; 456 for (j = 0; j < ATH9K_NF_CAL_HIST_MAX; j++) 457 h[i].nfCalBuffer[j] = h[i].privNF; 458 if (++k >= AR5416_MAX_CHAINS) 459 k = 0; 460 } 461 } 462 463 464 void ath9k_hw_bstuck_nfcal(struct ath_hw *ah) 465 { 466 struct ath9k_hw_cal_data *caldata = ah->caldata; 467 468 if (unlikely(!caldata)) 469 return; 470 471 /* 472 * If beacons are stuck, the most likely cause is interference. 473 * Triggering a noise floor calibration at this point helps the 474 * hardware adapt to a noisy environment much faster. 475 * To ensure that we recover from stuck beacons quickly, let 476 * the baseband update the internal NF value itself, similar to 477 * what is being done after a full reset. 478 */ 479 if (!test_bit(NFCAL_PENDING, &caldata->cal_flags)) 480 ath9k_hw_start_nfcal(ah, true); 481 else if (!(REG_READ(ah, AR_PHY_AGC_CONTROL) & AR_PHY_AGC_CONTROL_NF)) 482 ath9k_hw_getnf(ah, ah->curchan); 483 484 set_bit(NFCAL_INTF, &caldata->cal_flags); 485 } 486 EXPORT_SYMBOL(ath9k_hw_bstuck_nfcal); 487 488