ADC & I/Q calibrations could take infinite time to comple, since they
depend on received frames. In particular the I/Q mismatch calibration
requires receiving of OFDM frames for completion. But in the 2.4GHz
band, a station could receive only CCK frames for a very long time.
And while we wait for the completion of one of the mentioned
calibrations, the NF calibration is blocked. Moreover, in some
environments, I/Q calibration is unable to complete until a correct
noise calibration will be performed due to AGC behaviour.
In order to avoid delaying NF calibration on forever, limit the maximum
duration of ADCs & I/Q calibrations. If the calibration is not completed
within the maximum time, it will be interrupted and a next calibration
will be performed. The code that selects the next calibration has been
reworked to the loop so incompleted calibration will be respinned later.
А maximum calibration time of 30 seconds was selected to give the
calibration enough time to complete and to not interfere with the long
(NF) calibration.
Run tested with AR9220.
Signed-off-by: Sergey Ryazanov <ryazanov.s.a@xxxxxxxxx>
---
drivers/net/wireless/ath/ath9k/ar9002_calib.c | 25 +++++++++++++++++--
drivers/net/wireless/ath/ath9k/calib.c | 1 +
drivers/net/wireless/ath/ath9k/hw.h | 1 +
3 files changed, 25 insertions(+), 2 deletions(-)
diff --git a/drivers/net/wireless/ath/ath9k/ar9002_calib.c b/drivers/net/wireless/ath/ath9k/ar9002_calib.c
index 68188f500949..fd53b5f9e9b5 100644
--- a/drivers/net/wireless/ath/ath9k/ar9002_calib.c
+++ b/drivers/net/wireless/ath/ath9k/ar9002_calib.c
@@ -19,6 +19,8 @@
#include "ar9002_phy.h"
#define AR9285_CLCAL_REDO_THRESH 1
+/* AGC & I/Q calibrations time limit, ms */
+#define AR9002_CAL_MAX_TIME 30000
enum ar9002_cal_types {
ADC_GAIN_CAL = BIT(0),
@@ -104,6 +106,14 @@ static bool ar9002_hw_per_calibration(struct ath_hw *ah,
} else {
ar9002_hw_setup_calibration(ah, currCal);
}
+ } else if (time_after(jiffies, ah->cal_start_time +
+ msecs_to_jiffies(AR9002_CAL_MAX_TIME))) {
+ REG_CLR_BIT(ah, AR_PHY_TIMING_CTRL4(0),
+ AR_PHY_TIMING_CTRL4_DO_CAL);
+ ath_dbg(ath9k_hw_common(ah), CALIBRATE,
+ "calibration timeout\n");
+ currCal->calState = CAL_WAITING; /* Try later */
+ iscaldone = true;
}
} else if (!(caldata->CalValid & currCal->calData->calType)) {
ath9k_hw_reset_calibration(ah, currCal);
@@ -679,8 +689,19 @@ static int ar9002_hw_calibrate(struct ath_hw *ah, struct ath9k_channel *chan,
if (!ar9002_hw_per_calibration(ah, chan, rxchainmask, currCal))
return 0;
- ah->cal_list_curr = currCal = currCal->calNext;
- percal_pending = currCal->calState == CAL_WAITING;
+ /* Looking for next waiting calibration if any */
+ for (currCal = currCal->calNext; currCal != ah->cal_list_curr;
+ currCal = currCal->calNext) {
+ if (currCal->calState == CAL_WAITING)
+ break;
+ }
+ if (currCal->calState == CAL_WAITING) {
+ percal_pending = true;
+ ah->cal_list_curr = currCal;
+ } else {
+ percal_pending = false;
+ ah->cal_list_curr = ah->cal_list;
+ }
}
/* Do not start a next calibration if the longcal is in action */
diff --git a/drivers/net/wireless/ath/ath9k/calib.c b/drivers/net/wireless/ath/ath9k/calib.c
index 2ac3eefd3851..0422a33395b7 100644
--- a/drivers/net/wireless/ath/ath9k/calib.c
+++ b/drivers/net/wireless/ath/ath9k/calib.c
@@ -176,6 +176,7 @@ void ath9k_hw_reset_calibration(struct ath_hw *ah,
ath9k_hw_setup_calibration(ah, currCal);
+ ah->cal_start_time = jiffies;
currCal->calState = CAL_RUNNING;
for (i = 0; i < AR5416_MAX_CHAINS; i++) {
diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h
index c99f3c77c823..023599e10dd5 100644
--- a/drivers/net/wireless/ath/ath9k/hw.h
+++ b/drivers/net/wireless/ath/ath9k/hw.h
@@ -834,6 +834,7 @@ struct ath_hw {
/* Calibration */
u32 supp_cals;
+ unsigned long cal_start_time;
struct ath9k_cal_list iq_caldata;
struct ath9k_cal_list adcgain_caldata;
struct ath9k_cal_list adcdc_caldata;
--
2.24.1
