ath5k: treat RXORN as non-fatal

We get RXORN interrupts when all receive buffers are full. This is not
necessarily a fatal situation. It can also happen when the bus is busy or the
CPU is not fast enough to process all frames.

Older chipsets apparently need a reset to come out of this situration, but on
newer chips we can treat RXORN like RX, as going thru a full reset does more
harm than good, there.

The exact chip revisions which need a reset are unknown - this guess
AR5K_SREV_AR5212 ("venice") is copied from the HAL.

Inspired by openwrt 413-rxorn.patch:
"treat rxorn like rx, reset after rxorn seems to do more harm than good"

Signed-off-by: Bruno Randolf <br1@einfach.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

2 files changed, 15 insertions, 1 deletions

diff --git a/drivers/net/wireless/ath/ath5k/base.c b/drivers/net/wireless/ath/ath5k/base.c
index 3f59bc2d7912..92327423325f 100644
--- a/drivers/net/wireless/ath/ath5k/base.c
+++ b/drivers/net/wireless/ath/ath5k/base.c
@@ -2705,7 +2705,20 @@ ath5k_intr(int irq, void *dev_id)
                          */
                         tasklet_schedule(&sc->restq);
                 } else if (unlikely(status & AR5K_INT_RXORN)) {
-                        tasklet_schedule(&sc->restq);
+                        /*
+                         * Receive buffers are full. Either the bus is busy or
+                         * the CPU is not fast enough to process all received
+                         * frames.
+                         * Older chipsets need a reset to come out of this
+                         * condition, but we treat it as RX for newer chips.
+                         * We don't know exactly which versions need a reset -
+                         * this guess is copied from the HAL.
+                         */
+                        sc->stats.rxorn_intr++;
+                        if (ah->ah_mac_srev < AR5K_SREV_AR5212)
+                                tasklet_schedule(&sc->restq);
+                        else
+                                tasklet_schedule(&sc->rxtq);
                 } else {
                         if (status & AR5K_INT_SWBA) {
                                 tasklet_hi_schedule(&sc->beacontq);
diff --git a/drivers/net/wireless/ath/ath5k/base.h b/drivers/net/wireless/ath/ath5k/base.h
index 53a5651c57a2..56221bc7c8cd 100644
--- a/drivers/net/wireless/ath/ath5k/base.h
+++ b/drivers/net/wireless/ath/ath5k/base.h
@@ -135,6 +135,7 @@ struct ath5k_statistics {
         unsigned int beacons;
 
         unsigned int mib_intr;
+        unsigned int rxorn_intr;
 };
 
 #if CHAN_DEBUG