[PATCH 1/4 v2] ath10k: add debugging for tx-credits usage

[greearb at candelatech.com]

From: Ben Greear <greearb at candelatech.com>

This helps track tx credits accounting and usage.  If
firmware hangs or otherwise fails to return credits, one
can more easily see the last few command types that
was sent to the firmware.

Signed-off-by: Ben Greear <greearb at candelatech.com>
---

v2:  Improve comments.  Issue of using __LINE__ is not resolved.

 drivers/net/wireless/ath/ath10k/htc.c    | 16 ++++++++++------
 drivers/net/wireless/ath/ath10k/htc.h    |  6 +++++-
 drivers/net/wireless/ath/ath10k/htt_tx.c |  8 ++++----
 drivers/net/wireless/ath/ath10k/wmi.c    |  5 ++++-
 4 files changed, 23 insertions(+), 12 deletions(-)

diff --git a/drivers/net/wireless/ath/ath10k/htc.c b/drivers/net/wireless/ath/ath10k/htc.c
index 7f1bccd..2f8bc33 100644
--- a/drivers/net/wireless/ath/ath10k/htc.c
+++ b/drivers/net/wireless/ath/ath10k/htc.c
@@ -121,7 +121,7 @@ static void ath10k_htc_prepare_tx_skb(struct ath10k_htc_ep *ep,
 
 int ath10k_htc_send(struct ath10k_htc *htc,
 		    enum ath10k_htc_ep_id eid,
-		    struct sk_buff *skb)
+		    struct sk_buff *skb, int dbg)
 {
 	struct ath10k_htc_ep *ep = &htc->endpoint[eid];
 	struct ath10k_skb_cb *skb_cb = ATH10K_SKB_CB(skb);
@@ -157,6 +157,10 @@ int ath10k_htc_send(struct ath10k_htc *htc,
 			goto err_pull;
 		}
 		ep->tx_credits -= credits;
+		ath10k_dbg(ATH10K_DBG_HTC,
+			   "ep %d used %d credits, remaining %d dbg %d (0x%x)\n",
+			   eid, credits, ep->tx_credits, dbg, dbg);
+
 		spin_unlock_bh(&htc->tx_lock);
 	}
 
@@ -234,12 +238,12 @@ ath10k_htc_process_credit_report(struct ath10k_htc *htc,
 		if (report->eid >= ATH10K_HTC_EP_COUNT)
 			break;
 
-		ath10k_dbg(ATH10K_DBG_HTC, "ep %d got %d credits\n",
-			   report->eid, report->credits);
-
 		ep = &htc->endpoint[report->eid];
 		ep->tx_credits += report->credits;
 
+		ath10k_dbg(ATH10K_DBG_HTC, "ep %d got %d credits tot %d\n",
+			   report->eid, report->credits, ep->tx_credits);
+
 		if (ep->ep_ops.ep_tx_credits) {
 			spin_unlock_bh(&htc->tx_lock);
 			ep->ep_ops.ep_tx_credits(htc->ar);
@@ -669,7 +673,7 @@ int ath10k_htc_connect_service(struct ath10k_htc *htc,
 
 	reinit_completion(&htc->ctl_resp);
 
-	status = ath10k_htc_send(htc, ATH10K_HTC_EP_0, skb);
+	status = ath10k_htc_send(htc, ATH10K_HTC_EP_0, skb, __LINE__);
 	if (status) {
 		kfree_skb(skb);
 		return status;
@@ -815,7 +819,7 @@ int ath10k_htc_start(struct ath10k_htc *htc)
 
 	ath10k_dbg(ATH10K_DBG_HTC, "HTC is using TX credit flow control\n");
 
-	status = ath10k_htc_send(htc, ATH10K_HTC_EP_0, skb);
+	status = ath10k_htc_send(htc, ATH10K_HTC_EP_0, skb, __LINE__);
 	if (status) {
 		kfree_skb(skb);
 		return status;
diff --git a/drivers/net/wireless/ath/ath10k/htc.h b/drivers/net/wireless/ath/ath10k/htc.h
index 4716d33..b74b07f 100644
--- a/drivers/net/wireless/ath/ath10k/htc.h
+++ b/drivers/net/wireless/ath/ath10k/htc.h
@@ -355,8 +355,12 @@ int ath10k_htc_start(struct ath10k_htc *htc);
 int ath10k_htc_connect_service(struct ath10k_htc *htc,
 			       struct ath10k_htc_svc_conn_req  *conn_req,
 			       struct ath10k_htc_svc_conn_resp *conn_resp);
+/* dbg is used for logging, trying to track roughly what kind of command
+ * we are sending and/or where it came from.  May help debug firmware
+ * issues where we do not get tx-credits returned properly.
+ */
 int ath10k_htc_send(struct ath10k_htc *htc, enum ath10k_htc_ep_id eid,
-		    struct sk_buff *packet);
+		    struct sk_buff *packet, int dbg);
 void ath10k_htc_stop(struct ath10k_htc *htc);
 struct sk_buff *ath10k_htc_alloc_skb(int size);
 
diff --git a/drivers/net/wireless/ath/ath10k/htt_tx.c b/drivers/net/wireless/ath/ath10k/htt_tx.c
index 7a3e2e4..22a4542 100644
--- a/drivers/net/wireless/ath/ath10k/htt_tx.c
+++ b/drivers/net/wireless/ath/ath10k/htt_tx.c
@@ -173,7 +173,7 @@ int ath10k_htt_h2t_ver_req_msg(struct ath10k_htt *htt)
 	cmd = (struct htt_cmd *)skb->data;
 	cmd->hdr.msg_type = HTT_H2T_MSG_TYPE_VERSION_REQ;
 
-	ret = ath10k_htc_send(&htt->ar->htc, htt->eid, skb);
+	ret = ath10k_htc_send(&htt->ar->htc, htt->eid, skb, __LINE__);
 	if (ret) {
 		dev_kfree_skb_any(skb);
 		return ret;
@@ -212,7 +212,7 @@ int ath10k_htt_h2t_stats_req(struct ath10k_htt *htt, u8 mask, u64 cookie)
 	req->cookie_lsb = cpu_to_le32(cookie & 0xffffffff);
 	req->cookie_msb = cpu_to_le32((cookie & 0xffffffff00000000ULL) >> 32);
 
-	ret = ath10k_htc_send(&htt->ar->htc, htt->eid, skb);
+	ret = ath10k_htc_send(&htt->ar->htc, htt->eid, skb, __LINE__);
 	if (ret) {
 		ath10k_warn("failed to send htt type stats request: %d", ret);
 		dev_kfree_skb_any(skb);
@@ -298,7 +298,7 @@ int ath10k_htt_send_rx_ring_cfg_ll(struct ath10k_htt *htt)
 
 #undef desc_offset
 
-	ret = ath10k_htc_send(&htt->ar->htc, htt->eid, skb);
+	ret = ath10k_htc_send(&htt->ar->htc, htt->eid, skb, __LINE__);
 	if (ret) {
 		dev_kfree_skb_any(skb);
 		return ret;
@@ -360,7 +360,7 @@ int ath10k_htt_mgmt_tx(struct ath10k_htt *htt, struct sk_buff *msdu)
 
 	skb_cb->htt.txbuf = NULL;
 
-	res = ath10k_htc_send(&htt->ar->htc, htt->eid, txdesc);
+	res = ath10k_htc_send(&htt->ar->htc, htt->eid, txdesc, __LINE__);
 	if (res)
 		goto err_unmap_msdu;
 
diff --git a/drivers/net/wireless/ath/ath10k/wmi.c b/drivers/net/wireless/ath/ath10k/wmi.c
index d4b48ef..433ec5a 100644
--- a/drivers/net/wireless/ath/ath10k/wmi.c
+++ b/drivers/net/wireless/ath/ath10k/wmi.c
@@ -544,7 +544,10 @@ static int ath10k_wmi_cmd_send_nowait(struct ath10k *ar, struct sk_buff *skb,
 	cmd_hdr->cmd_id = __cpu_to_le32(cmd);
 
 	memset(skb_cb, 0, sizeof(*skb_cb));
-	ret = ath10k_htc_send(&ar->htc, ar->wmi.eid, skb);
+	/* 0x71100000 is hack so that we know the debug value is a cmd-id
+	 * instead of a line number.
+	 */
+	ret = ath10k_htc_send(&ar->htc, ar->wmi.eid, skb, 0x71100000 | cmd_id);
 	trace_ath10k_wmi_cmd(cmd_id, skb->data, skb->len, ret);
 
 	if (ret)
-- 
1.7.11.7