iwlwifi: fix ucode assertion for RX queue overrun

This patch allows the driver to restock the RX queue early if the RX
queue is almost empty. This will help on avoiding any ucode assert
for the RX overrun problem.

Signed-off-by: Mohamed Abbas <mabbas@linux.intel.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 36 insertions, 2 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl4965-base.c b/drivers/net/wireless/iwlwifi/iwl4965-base.c
index 670f611adf9..6be38ce701f 100644
--- a/drivers/net/wireless/iwlwifi/iwl4965-base.c
+++ b/drivers/net/wireless/iwlwifi/iwl4965-base.c
@@ -4477,9 +4477,8 @@ static int iwl4965_rx_queue_restock(struct iwl4965_priv *priv)
  * Also restock the Rx queue via iwl4965_rx_queue_restock.
  * This is called as a scheduled work item (except for during initialization)
  */
-void iwl4965_rx_replenish(void *data)
+static void iwl4965_rx_allocate(struct iwl4965_priv *priv)
 {
-	struct iwl4965_priv *priv = data;
 	struct iwl4965_rx_queue *rxq = &priv->rxq;
 	struct list_head *element;
 	struct iwl4965_rx_mem_buffer *rxb;
@@ -4512,6 +4511,26 @@ void iwl4965_rx_replenish(void *data)
 		rxq->free_count++;
 	}
 	spin_unlock_irqrestore(&rxq->lock, flags);
+}
+
+/*
+ * this should be called while priv->lock is locked
+*/
+void __iwl4965_rx_replenish(void *data)
+{
+	struct iwl4965_priv *priv = data;
+
+	iwl4965_rx_allocate(priv);
+	iwl4965_rx_queue_restock(priv);
+}
+
+
+void iwl4965_rx_replenish(void *data)
+{
+	struct iwl4965_priv *priv = data;
+	unsigned long flags;
+
+	iwl4965_rx_allocate(priv);
 
 	spin_lock_irqsave(&priv->lock, flags);
 	iwl4965_rx_queue_restock(priv);
@@ -4689,6 +4708,8 @@ static void iwl4965_rx_handle(struct iwl4965_priv *priv)
 	u32 r, i;
 	int reclaim;
 	unsigned long flags;
+	u8 fill_rx = 0;
+	u32 count = 0;
 
 	/* uCode's read index (stored in shared DRAM) indicates the last Rx
 	 * buffer that the driver may process (last buffer filled by ucode). */
@@ -4699,6 +4720,9 @@ static void iwl4965_rx_handle(struct iwl4965_priv *priv)
 	if (i == r)
 		IWL_DEBUG(IWL_DL_RX | IWL_DL_ISR, "r = %d, i = %d\n", r, i);
 
+	if (iwl4965_rx_queue_space(rxq) > (RX_QUEUE_SIZE / 2))
+		fill_rx = 1;
+
 	while (i != r) {
 		rxb = rxq->queue[i];
 
@@ -4768,6 +4792,16 @@ static void iwl4965_rx_handle(struct iwl4965_priv *priv)
 		list_add_tail(&rxb->list, &priv->rxq.rx_used);
 		spin_unlock_irqrestore(&rxq->lock, flags);
 		i = (i + 1) & RX_QUEUE_MASK;
+		/* If there are a lot of unused frames,
+		 * restock the Rx queue so ucode wont assert. */
+		if (fill_rx) {
+			count++;
+			if (count >= 8) {
+				priv->rxq.read = i;
+				__iwl4965_rx_replenish(priv);
+				count = 0;
+			}
+		}
 	}
 
 	/* Backtrack one entry */