iwlagn: warn about buggy fw that doesn't set SEQ_RX_FRAME

The way we check if there is host command that should be reclaimed is
way too complicated. We should have a clear indication from the fw.
The fw is expected to set the SEQ_RX_FRAME bit if the frame was
originated by the fw which indicates to the driver that there is no
host command to free.
Somehow, there seem to have been buggy fw out there, hence the very
old comment.

This code checks if we have still buggy fw out there.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NWey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

drivers/net/wireless/iwlwifi/iwl-trans-rx-pcie.c

@@ -398,6 +398,7 @@ static void iwl_rx_handle(struct iwl_trans *trans)
 
 	while (i != r) {
 		int len;
+		u16 txq_id, sequence;
 
 		rxb = rxq->queue[i];
 
@@ -437,6 +438,17 @@ static void iwl_rx_handle(struct iwl_trans *trans)
 			(pkt->hdr.cmd != STATISTICS_NOTIFICATION) &&
 			(pkt->hdr.cmd != REPLY_TX);
 
+		sequence = le16_to_cpu(pkt->hdr.sequence);
+		txq_id = SEQ_TO_QUEUE(le16_to_cpu(pkt->hdr.sequence));
+
+		/* warn if this is cmd response / notification and the uCode
+		 * didn't set the SEQ_RX_FRAME for a frame that is
+		 * uCode-originated*/
+		WARN(txq_id == trans->shrd->cmd_queue && reclaim == false &&
+		     (!(pkt->hdr.sequence & SEQ_RX_FRAME)),
+		     "reclaim is false, SEQ_RX_FRAME unset: %s\n",
+		     get_cmd_string(pkt->hdr.cmd));
+
 		iwl_rx_dispatch(priv(trans), rxb);
 
 		/*