ath9k: restart hardware after noise floor calibration failure

When NF calibration fails, the radio often becomes deaf. The usual
hardware hang checks do not detect this, so it's better to issue a reset
when that happens.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

9 files changed, 33 insertions, 24 deletions

diff --git a/drivers/net/wireless/ath/ath9k/ar9002_calib.c b/drivers/net/wireless/ath/ath9k/ar9002_calib.c
index cdc74005650c..6bfdebfcdeef 100644
--- a/drivers/net/wireless/ath/ath9k/ar9002_calib.c
+++ b/drivers/net/wireless/ath/ath9k/ar9002_calib.c
@@ -657,14 +657,13 @@ static void ar9002_hw_olc_temp_compensation(struct ath_hw *ah)
                 ar9280_hw_olc_temp_compensation(ah);
 }
 
-static bool ar9002_hw_calibrate(struct ath_hw *ah,
-                                struct ath9k_channel *chan,
-                                u8 rxchainmask,
-                                bool longcal)
+static int ar9002_hw_calibrate(struct ath_hw *ah, struct ath9k_channel *chan,
+                               u8 rxchainmask, bool longcal)
 {
         bool iscaldone = true;
         struct ath9k_cal_list *currCal = ah->cal_list_curr;
         bool nfcal, nfcal_pending = false;
+        int ret;
 
         nfcal = !!(REG_READ(ah, AR_PHY_AGC_CONTROL) & AR_PHY_AGC_CONTROL_NF);
         if (ah->caldata)
@@ -698,7 +697,9 @@ static bool ar9002_hw_calibrate(struct ath_hw *ah,
                          * NF is slow time-variant, so it is OK to use a
                          * historical value.
                          */
-                        ath9k_hw_loadnf(ah, ah->curchan);
+                        ret = ath9k_hw_loadnf(ah, ah->curchan);
+                        if (ret < 0)
+                                return ret;
                 }
 
                 if (longcal) {
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_calib.c b/drivers/net/wireless/ath/ath9k/ar9003_calib.c
index ac8301ef5242..06ab71db6e80 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_calib.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_calib.c
@@ -121,13 +121,12 @@ static bool ar9003_hw_per_calibration(struct ath_hw *ah,
         return iscaldone;
 }
 
-static bool ar9003_hw_calibrate(struct ath_hw *ah,
-                                struct ath9k_channel *chan,
-                                u8 rxchainmask,
-                                bool longcal)
+static int ar9003_hw_calibrate(struct ath_hw *ah, struct ath9k_channel *chan,
+                               u8 rxchainmask, bool longcal)
 {
         bool iscaldone = true;
         struct ath9k_cal_list *currCal = ah->cal_list_curr;
+        int ret;
 
         /*
          * For given calibration:
@@ -163,7 +162,9 @@ static bool ar9003_hw_calibrate(struct ath_hw *ah,
                  * NF is slow time-variant, so it is OK to use a historical
                  * value.
                  */
-                ath9k_hw_loadnf(ah, ah->curchan);
+                ret = ath9k_hw_loadnf(ah, ah->curchan);
+                if (ret < 0)
+                        return ret;
 
                 /* start NF calibration, without updating BB NF register */
                 ath9k_hw_start_nfcal(ah, false);
diff --git a/drivers/net/wireless/ath/ath9k/calib.c b/drivers/net/wireless/ath/ath9k/calib.c
index 278365b8a895..e200a6e3aca5 100644
--- a/drivers/net/wireless/ath/ath9k/calib.c
+++ b/drivers/net/wireless/ath/ath9k/calib.c
@@ -234,7 +234,7 @@ void ath9k_hw_start_nfcal(struct ath_hw *ah, bool update)
         REG_SET_BIT(ah, AR_PHY_AGC_CONTROL, AR_PHY_AGC_CONTROL_NF);
 }
 
-void ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan)
+int ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan)
 {
         struct ath9k_nfcal_hist *h = NULL;
         unsigned i, j;
@@ -301,7 +301,7 @@ void ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan)
                 ath_dbg(common, ANY,
                         "Timeout while waiting for nf to load: AR_PHY_AGC_CONTROL=0x%x\n",
                         REG_READ(ah, AR_PHY_AGC_CONTROL));
-                return;
+                return -ETIMEDOUT;
         }
 
         /*
@@ -322,6 +322,8 @@ void ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan)
                 }
         }
         REGWRITE_BUFFER_FLUSH(ah);
+
+        return 0;
 }
 
 
diff --git a/drivers/net/wireless/ath/ath9k/calib.h b/drivers/net/wireless/ath/ath9k/calib.h
index b8ed95e9a335..87badf4bb8a4 100644
--- a/drivers/net/wireless/ath/ath9k/calib.h
+++ b/drivers/net/wireless/ath/ath9k/calib.h
@@ -109,7 +109,7 @@ struct ath9k_pacal_info{
 
 bool ath9k_hw_reset_calvalid(struct ath_hw *ah);
 void ath9k_hw_start_nfcal(struct ath_hw *ah, bool update);
-void ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan);
+int ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan);
 bool ath9k_hw_getnf(struct ath_hw *ah, struct ath9k_channel *chan);
 void ath9k_init_nfcal_hist_buffer(struct ath_hw *ah,
                                   struct ath9k_channel *chan);
diff --git a/drivers/net/wireless/ath/ath9k/debug.c b/drivers/net/wireless/ath/ath9k/debug.c
index cf4a98b98cf3..2a2a17df5fb3 100644
--- a/drivers/net/wireless/ath/ath9k/debug.c
+++ b/drivers/net/wireless/ath/ath9k/debug.c
@@ -863,6 +863,7 @@ static ssize_t read_file_reset(struct file *file, char __user *user_buf,
                 [RESET_TYPE_MAC_HANG] = "MAC Hang",
                 [RESET_TYPE_BEACON_STUCK] = "Stuck Beacon",
                 [RESET_TYPE_MCI] = "MCI Reset",
+                [RESET_TYPE_CALIBRATION] = "Calibration error",
         };
         char buf[512];
         unsigned int len = 0;
diff --git a/drivers/net/wireless/ath/ath9k/debug.h b/drivers/net/wireless/ath/ath9k/debug.h
index 53ae15bd0c9d..bd75b1f716db 100644
--- a/drivers/net/wireless/ath/ath9k/debug.h
+++ b/drivers/net/wireless/ath/ath9k/debug.h
@@ -49,6 +49,7 @@ enum ath_reset_type {
         RESET_TYPE_MAC_HANG,
         RESET_TYPE_BEACON_STUCK,
         RESET_TYPE_MCI,
+        RESET_TYPE_CALIBRATION,
         __RESET_TYPE_MAX
 };
 
diff --git a/drivers/net/wireless/ath/ath9k/hw-ops.h b/drivers/net/wireless/ath/ath9k/hw-ops.h
index 8e85efeaeffc..88769b64b20b 100644
--- a/drivers/net/wireless/ath/ath9k/hw-ops.h
+++ b/drivers/net/wireless/ath/ath9k/hw-ops.h
@@ -41,10 +41,9 @@ static inline void ath9k_hw_set_desc_link(struct ath_hw *ah, void *ds,
         ath9k_hw_ops(ah)->set_desc_link(ds, link);
 }
 
-static inline bool ath9k_hw_calibrate(struct ath_hw *ah,
-                                      struct ath9k_channel *chan,
-                                      u8 rxchainmask,
-                                      bool longcal)
+static inline int ath9k_hw_calibrate(struct ath_hw *ah,
+                                     struct ath9k_channel *chan,
+                                     u8 rxchainmask, bool longcal)
 {
         return ath9k_hw_ops(ah)->calibrate(ah, chan, rxchainmask, longcal);
 }
diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h
index 7a81f5b864c7..f204099c38b8 100644
--- a/drivers/net/wireless/ath/ath9k/hw.h
+++ b/drivers/net/wireless/ath/ath9k/hw.h
@@ -688,10 +688,8 @@ struct ath_hw_ops {
                                      bool power_off);
         void (*rx_enable)(struct ath_hw *ah);
         void (*set_desc_link)(void *ds, u32 link);
-        bool (*calibrate)(struct ath_hw *ah,
-                          struct ath9k_channel *chan,
-                          u8 rxchainmask,
-                          bool longcal);
+        int (*calibrate)(struct ath_hw *ah, struct ath9k_channel *chan,
+                         u8 rxchainmask, bool longcal);
         bool (*get_isr)(struct ath_hw *ah, enum ath9k_int *masked,
                         u32 *sync_cause_p);
         void (*set_txdesc)(struct ath_hw *ah, void *ds,
diff --git a/drivers/net/wireless/ath/ath9k/link.c b/drivers/net/wireless/ath/ath9k/link.c
index 2343f56e6498..b829263e3d0a 100644
--- a/drivers/net/wireless/ath/ath9k/link.c
+++ b/drivers/net/wireless/ath/ath9k/link.c
@@ -371,9 +371,15 @@ void ath_ani_calibrate(unsigned long data)
 
         /* Perform calibration if necessary */
         if (longcal || shortcal) {
-                common->ani.caldone =
-                        ath9k_hw_calibrate(ah, ah->curchan,
-                                           ah->rxchainmask, longcal);
+                int ret = ath9k_hw_calibrate(ah, ah->curchan, ah->rxchainmask,
+                                             longcal);
+                if (ret < 0) {
+                        common->ani.caldone = 0;
+                        ath9k_queue_reset(sc, RESET_TYPE_CALIBRATION);
+                        return;
+                }
+
+                common->ani.caldone = ret;
         }
 
         ath_dbg(common, ANI,