ath5k: Use SWI to trigger calibration
* Get rid of calibration timer, instead use a software interrupt
to schedule the calibration tasklet.
a) We don't need a timer for this, there is no need for accuracy
even with round_jiffies i think this is a waste of resources.
Also we don't need to run calibration if we are idle (no
interrupts).
b) When we add ANI support we 'll just extend the poll function
and calibration tasklet and handle all periodic phy calibration
on one place (much cleaner).
c) Having calibration on a tasklet is better since during calibration
we can't transmit or receive (antennas are detached to measure
noise floor), previously calibration could run in parallel with
tx/rx and interfere (packet loss).
v2: kill tasklet on stop_hw, stop/wake queues
v3: use time_is_before_eq_jiffies to compare timestamp with current
time
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath5k/ath5k.h b/drivers/net/wireless/ath/ath5k/ath5k.h
index 1047a6c..c09402e 100644
--- a/drivers/net/wireless/ath/ath5k/ath5k.h
+++ b/drivers/net/wireless/ath/ath5k/ath5k.h
@@ -919,6 +919,12 @@
AR5K_INT_NOCARD = 0xffffffff
};
+/* Software interrupts used for calibration */
+enum ath5k_software_interrupt {
+ AR5K_SWI_FULL_CALIBRATION = 0x01,
+ AR5K_SWI_SHORT_CALIBRATION = 0x02,
+};
+
/*
* Power management
*/
@@ -1123,6 +1129,15 @@
/* noise floor from last periodic calibration */
s32 ah_noise_floor;
+ /* Calibration timestamp */
+ unsigned long ah_cal_tstamp;
+
+ /* Calibration interval (secs) */
+ u8 ah_cal_intval;
+
+ /* Software interrupt mask */
+ u8 ah_swi_mask;
+
/*
* Function pointers
*/
@@ -1276,6 +1291,7 @@
/* PHY calibration */
extern int ath5k_hw_phy_calibrate(struct ath5k_hw *ah, struct ieee80211_channel *channel);
extern int ath5k_hw_noise_floor_calibration(struct ath5k_hw *ah, short freq);
+extern void ath5k_hw_calibration_poll(struct ath5k_hw *ah);
/* Spur mitigation */
bool ath5k_hw_chan_has_spur_noise(struct ath5k_hw *ah,
struct ieee80211_channel *channel);
diff --git a/drivers/net/wireless/ath/ath5k/base.c b/drivers/net/wireless/ath/ath5k/base.c
index 0370cba..acbcfc2 100644
--- a/drivers/net/wireless/ath/ath5k/base.c
+++ b/drivers/net/wireless/ath/ath5k/base.c
@@ -59,7 +59,7 @@
#include "reg.h"
#include "debug.h"
-static int ath5k_calinterval = 10; /* Calibrate PHY every 10 secs (TODO: Fixme) */
+static u8 ath5k_calinterval = 10; /* Calibrate PHY every 10 secs (TODO: Fixme) */
static int modparam_nohwcrypt;
module_param_named(nohwcrypt, modparam_nohwcrypt, bool, S_IRUGO);
MODULE_PARM_DESC(nohwcrypt, "Disable hardware encryption.");
@@ -376,7 +376,7 @@
static irqreturn_t ath5k_intr(int irq, void *dev_id);
static void ath5k_tasklet_reset(unsigned long data);
-static void ath5k_calibrate(unsigned long data);
+static void ath5k_tasklet_calibrate(unsigned long data);
/*
* Module init/exit functions
@@ -799,8 +799,8 @@
tasklet_init(&sc->rxtq, ath5k_tasklet_rx, (unsigned long)sc);
tasklet_init(&sc->txtq, ath5k_tasklet_tx, (unsigned long)sc);
tasklet_init(&sc->restq, ath5k_tasklet_reset, (unsigned long)sc);
+ tasklet_init(&sc->calib, ath5k_tasklet_calibrate, (unsigned long)sc);
tasklet_init(&sc->beacontq, ath5k_tasklet_beacon, (unsigned long)sc);
- setup_timer(&sc->calib_tim, ath5k_calibrate, (unsigned long)sc);
ret = ath5k_eeprom_read_mac(ah, mac);
if (ret) {
@@ -2364,7 +2364,7 @@
sc->curband = &sc->sbands[sc->curchan->band];
sc->imask = AR5K_INT_RXOK | AR5K_INT_RXERR | AR5K_INT_RXEOL |
AR5K_INT_RXORN | AR5K_INT_TXDESC | AR5K_INT_TXEOL |
- AR5K_INT_FATAL | AR5K_INT_GLOBAL;
+ AR5K_INT_FATAL | AR5K_INT_GLOBAL | AR5K_INT_SWI;
ret = ath5k_reset(sc, NULL);
if (ret)
goto done;
@@ -2381,8 +2381,8 @@
/* Set ack to be sent at low bit-rates */
ath5k_hw_set_ack_bitrate_high(ah, false);
- mod_timer(&sc->calib_tim, round_jiffies(jiffies +
- msecs_to_jiffies(ath5k_calinterval * 1000)));
+ /* Set PHY calibration inteval */
+ ah->ah_cal_intval = ath5k_calinterval;
ret = 0;
done:
@@ -2475,10 +2475,10 @@
mmiowb();
mutex_unlock(&sc->lock);
- del_timer_sync(&sc->calib_tim);
tasklet_kill(&sc->rxtq);
tasklet_kill(&sc->txtq);
tasklet_kill(&sc->restq);
+ tasklet_kill(&sc->calib);
tasklet_kill(&sc->beacontq);
ath5k_rfkill_hw_stop(sc->ah);
@@ -2534,6 +2534,9 @@
if (status & AR5K_INT_BMISS) {
/* TODO */
}
+ if (status & AR5K_INT_SWI) {
+ tasklet_schedule(&sc->calib);
+ }
if (status & AR5K_INT_MIB) {
/*
* These stats are also used for ANI i think
@@ -2550,6 +2553,8 @@
if (unlikely(!counter))
ATH5K_WARN(sc, "too many interrupts, giving up for now\n");
+ ath5k_hw_calibration_poll(ah);
+
return IRQ_HANDLED;
}
@@ -2566,11 +2571,19 @@
* for temperature/environment changes.
*/
static void
-ath5k_calibrate(unsigned long data)
+ath5k_tasklet_calibrate(unsigned long data)
{
struct ath5k_softc *sc = (void *)data;
struct ath5k_hw *ah = sc->ah;
+ /* Only full calibration for now */
+ if (ah->ah_swi_mask != AR5K_SWI_FULL_CALIBRATION)
+ return;
+
+ /* Stop queues so that calibration
+ * doesn't interfere with tx */
+ ieee80211_stop_queues(sc->hw);
+
ATH5K_DBG(sc, ATH5K_DEBUG_CALIBRATE, "channel %u/%x\n",
ieee80211_frequency_to_channel(sc->curchan->center_freq),
sc->curchan->hw_value);
@@ -2588,8 +2601,11 @@
ieee80211_frequency_to_channel(
sc->curchan->center_freq));
- mod_timer(&sc->calib_tim, round_jiffies(jiffies +
- msecs_to_jiffies(ath5k_calinterval * 1000)));
+ ah->ah_swi_mask = 0;
+
+ /* Wake queues */
+ ieee80211_wake_queues(sc->hw);
+
}
diff --git a/drivers/net/wireless/ath/ath5k/base.h b/drivers/net/wireless/ath/ath5k/base.h
index 778e422..667bd9d 100644
--- a/drivers/net/wireless/ath/ath5k/base.h
+++ b/drivers/net/wireless/ath/ath5k/base.h
@@ -177,6 +177,8 @@
struct ath5k_rfkill rf_kill;
+ struct tasklet_struct calib; /* calibration tasklet */
+
spinlock_t block; /* protects beacon */
struct tasklet_struct beacontq; /* beacon intr tasklet */
struct ath5k_buf *bbuf; /* beacon buffer */
@@ -187,7 +189,6 @@
unsigned int nexttbtt; /* next beacon time in TU */
struct ath5k_txq *cabq; /* content after beacon */
- struct timer_list calib_tim; /* calibration timer */
int power_level; /* Requested tx power in dbm */
bool assoc; /* assocate state */
bool enable_beacon; /* true if beacons are on */
diff --git a/drivers/net/wireless/ath/ath5k/phy.c b/drivers/net/wireless/ath/ath5k/phy.c
index 6afba98..298fcf0 100644
--- a/drivers/net/wireless/ath/ath5k/phy.c
+++ b/drivers/net/wireless/ath/ath5k/phy.c
@@ -1104,6 +1104,29 @@
PHY calibration
\*****************/
+void
+ath5k_hw_calibration_poll(struct ath5k_hw *ah)
+{
+ /* Calibration interval in jiffies */
+ unsigned long cal_intval;
+
+ cal_intval = msecs_to_jiffies(ah->ah_cal_intval * 1000);
+
+ /* Initialize timestamp if needed */
+ if (!ah->ah_cal_tstamp)
+ ah->ah_cal_tstamp = jiffies;
+
+ /* For now we always do full calibration
+ * Mark software interrupt mask and fire software
+ * interrupt (bit gets auto-cleared) */
+ if (time_is_before_eq_jiffies(ah->ah_cal_tstamp + cal_intval)) {
+ ah->ah_cal_tstamp = jiffies;
+ ah->ah_swi_mask = AR5K_SWI_FULL_CALIBRATION;
+ AR5K_REG_ENABLE_BITS(ah, AR5K_CR, AR5K_CR_SWI);
+ }
+
+}
+
/**
* ath5k_hw_noise_floor_calibration - perform PHY noise floor calibration
*