rt2800: initial watchdog implementation

Add watchdog for rt2800 devices. For now it only detect hung
and print error.

[Note: I verified that printing messages from process context is
fine on MT7620 (WT3020) platform that have problem when printk
is called from interrupt context].

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

diff --git a/drivers/net/wireless/ralink/rt2x00/rt2800lib.c b/drivers/net/wireless/ralink/rt2x00/rt2800lib.c
index 621cd4c..d420d75 100644 (file)
--- a/drivers/net/wireless/ralink/rt2x00/rt2800lib.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2800lib.c
@@ -1212,6 +1212,60 @@ void rt2800_txdone_nostatus(struct rt2x00_dev *rt2x00dev)
 }
 EXPORT_SYMBOL_GPL(rt2800_txdone_nostatus);
 
+static int rt2800_check_hung(struct data_queue *queue)
+{
+       unsigned int cur_idx = rt2800_drv_get_dma_done(queue);
+
+       if (queue->wd_idx != cur_idx)
+               queue->wd_count = 0;
+       else
+               queue->wd_count++;
+
+       return queue->wd_count > 16;
+}
+
+void rt2800_watchdog(struct rt2x00_dev *rt2x00dev)
+{
+       struct data_queue *queue;
+       bool hung_tx = false;
+       bool hung_rx = false;
+
+       if (test_bit(DEVICE_STATE_SCANNING, &rt2x00dev->flags))
+               return;
+
+       queue_for_each(rt2x00dev, queue) {
+               switch (queue->qid) {
+               case QID_AC_VO:
+               case QID_AC_VI:
+               case QID_AC_BE:
+               case QID_AC_BK:
+               case QID_MGMT:
+                       if (rt2x00queue_empty(queue))
+                               continue;
+                       hung_tx = rt2800_check_hung(queue);
+                       break;
+               case QID_RX:
+                       /* For station mode we should reactive at least
+                        * beacons. TODO: need to find good way detect
+                        * RX hung for AP mode.
+                        */
+                       if (rt2x00dev->intf_sta_count == 0)
+                               continue;
+                       hung_rx = rt2800_check_hung(queue);
+                       break;
+               default:
+                       break;
+               }
+       }
+
+       if (hung_tx)
+               rt2x00_warn(rt2x00dev, "Watchdog TX hung detected\n");
+
+       if (hung_rx)
+               rt2x00_warn(rt2x00dev, "Watchdog RX hung detected\n");
+}
+EXPORT_SYMBOL_GPL(rt2800_watchdog);
+
 static unsigned int rt2800_hw_beacon_base(struct rt2x00_dev *rt2x00dev,
                                          unsigned int index)
 {
@@ -10211,6 +10265,8 @@ int rt2800_probe_hw(struct rt2x00_dev *rt2x00dev)
                __set_bit(REQUIRE_TASKLET_CONTEXT, &rt2x00dev->cap_flags);
        }
 
+       rt2x00dev->link.watchdog_interval = msecs_to_jiffies(100);
+
        /*
         * Set the rssi offset.
         */

diff --git a/drivers/net/wireless/ralink/rt2x00/rt2800lib.h b/drivers/net/wireless/ralink/rt2x00/rt2800lib.h
index dbb413e..f35f4e2 100644 (file)
--- a/drivers/net/wireless/ralink/rt2x00/rt2800lib.h
+++ b/drivers/net/wireless/ralink/rt2x00/rt2800lib.h
@@ -197,6 +197,8 @@ void rt2800_txdone_nostatus(struct rt2x00_dev *rt2x00dev);
 bool rt2800_txstatus_timeout(struct rt2x00_dev *rt2x00dev);
 bool rt2800_txstatus_pending(struct rt2x00_dev *rt2x00dev);
 
+void rt2800_watchdog(struct rt2x00_dev *rt2x00dev);
+
 void rt2800_write_beacon(struct queue_entry *entry, struct txentry_desc *txdesc);
 void rt2800_clear_beacon(struct queue_entry *entry);
 

diff --git a/drivers/net/wireless/ralink/rt2x00/rt2800pci.c b/drivers/net/wireless/ralink/rt2x00/rt2800pci.c
index 71ef8f0..df6345a 100644 (file)
--- a/drivers/net/wireless/ralink/rt2x00/rt2800pci.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2800pci.c
@@ -351,6 +351,7 @@ static const struct rt2x00lib_ops rt2800pci_rt2x00_ops = {
        .link_tuner             = rt2800_link_tuner,
        .gain_calibration       = rt2800_gain_calibration,
        .vco_calibration        = rt2800_vco_calibration,
+       .watchdog               = rt2800_watchdog,
        .start_queue            = rt2800mmio_start_queue,
        .kick_queue             = rt2800mmio_kick_queue,
        .stop_queue             = rt2800mmio_stop_queue,

diff --git a/drivers/net/wireless/ralink/rt2x00/rt2800soc.c b/drivers/net/wireless/ralink/rt2x00/rt2800soc.c
index 34e9291..1054ade 100644 (file)
--- a/drivers/net/wireless/ralink/rt2x00/rt2800soc.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2800soc.c
@@ -196,6 +196,7 @@ static const struct rt2x00lib_ops rt2800soc_rt2x00_ops = {
        .link_tuner             = rt2800_link_tuner,
        .gain_calibration       = rt2800_gain_calibration,
        .vco_calibration        = rt2800_vco_calibration,
+       .watchdog               = rt2800_watchdog,
        .start_queue            = rt2800mmio_start_queue,
        .kick_queue             = rt2800mmio_kick_queue,
        .stop_queue             = rt2800mmio_stop_queue,

diff --git a/drivers/net/wireless/ralink/rt2x00/rt2800usb.c b/drivers/net/wireless/ralink/rt2x00/rt2800usb.c
index 9f23b18..da813df 100644 (file)
--- a/drivers/net/wireless/ralink/rt2x00/rt2800usb.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2800usb.c
@@ -687,6 +687,7 @@ static const struct rt2x00lib_ops rt2800usb_rt2x00_ops = {
        .link_tuner             = rt2800_link_tuner,
        .gain_calibration       = rt2800_gain_calibration,
        .vco_calibration        = rt2800_vco_calibration,
+       .watchdog               = rt2800_watchdog,
        .start_queue            = rt2800usb_start_queue,
        .kick_queue             = rt2x00usb_kick_queue,
        .stop_queue             = rt2800usb_stop_queue,

diff --git a/drivers/net/wireless/ralink/rt2x00/rt2x00queue.h b/drivers/net/wireless/ralink/rt2x00/rt2x00queue.h
index 099e747..23739dd 100644 (file)
--- a/drivers/net/wireless/ralink/rt2x00/rt2x00queue.h
+++ b/drivers/net/wireless/ralink/rt2x00/rt2x00queue.h
@@ -435,6 +435,9 @@ enum data_queue_flags {
  * @length: Number of frames in queue.
  * @index: Index pointers to entry positions in the queue,
  *     use &enum queue_index to get a specific index field.
+ * @wd_count: watchdog counter number of times entry does change
+ *      in the queue
+ * @wd_idx: index of queue entry saved by watchdog
  * @txop: maximum burst time.
  * @aifs: The aifs value for outgoing frames (field ignored in RX queue).
  * @cw_min: The cw min value for outgoing frames (field ignored in RX queue).
@@ -462,6 +465,9 @@ struct data_queue {
        unsigned short length;
        unsigned short index[Q_INDEX_MAX];
 
+       unsigned short wd_count;
+       unsigned int wd_idx;
+
        unsigned short txop;
        unsigned short aifs;
        unsigned short cw_min;