From 2472b924a409ae452065cd5726c5020cfa442698 Mon Sep 17 00:00:00 2001
From: Peter Chiu <chui-hao.chiu@mediatek.com>
Date: Mon, 18 Mar 2024 14:16:34 +0800
Subject: [PATCH 2013/2014] wifi: mt76: add debugfs for tx drop counters

Signed-off-by: Peter Chiu <chui-hao.chiu@mediatek.com>
---
 dma.c                | 26 +++++++++++++++++++++-----
 mt76.h               | 22 ++++++++++++++++++++++
 mt7915/mac.c         | 16 +++++++++++++---
 mt7915/mtk_debugfs.c | 37 +++++++++++++++++++++++++++++++++++++
 tx.c                 |  6 ++++++
 5 files changed, 99 insertions(+), 8 deletions(-)

diff --git a/dma.c b/dma.c
index d17fc88..da3e8bc 100644
--- a/dma.c
+++ b/dma.c
@@ -612,13 +612,18 @@ mt76_dma_tx_queue_skb(struct mt76_phy *phy, struct mt76_queue *q,
 	struct sk_buff *iter;
 	dma_addr_t addr;
 	u8 *txwi;
+	int reason = -1;
 
-	if (test_bit(MT76_RESET, &phy->state))
+	if (test_bit(MT76_RESET, &phy->state)) {
+		reason = MT_TX_DROP_RESET_STATE;
 		goto free_skb;
+	}
 
 	t = mt76_get_txwi(dev);
-	if (!t)
+	if (!t) {
+		reason = MT_TX_DROP_GET_TXWI_FAIL;
 		goto free_skb;
+	}
 
 	txwi = mt76_get_txwi_ptr(dev, t);
 
@@ -628,8 +633,10 @@ mt76_dma_tx_queue_skb(struct mt76_phy *phy, struct mt76_queue *q,
 
 	len = skb_headlen(skb);
 	addr = dma_map_single(dev->dma_dev, skb->data, len, DMA_TO_DEVICE);
-	if (unlikely(dma_mapping_error(dev->dma_dev, addr)))
+	if (unlikely(dma_mapping_error(dev->dma_dev, addr))) {
+		reason = MT_TX_DROP_DMA_FAIL;
 		goto free;
+	}
 
 	tx_info.buf[n].addr = t->dma_addr;
 	tx_info.buf[n++].len = dev->drv->txwi_size;
@@ -637,13 +644,17 @@ mt76_dma_tx_queue_skb(struct mt76_phy *phy, struct mt76_queue *q,
 	tx_info.buf[n++].len = len;
 
 	skb_walk_frags(skb, iter) {
-		if (n == ARRAY_SIZE(tx_info.buf))
+		if (n == ARRAY_SIZE(tx_info.buf)) {
+			reason = MT_TX_DROP_AGG_EXCEEDED;
 			goto unmap;
+		}
 
 		addr = dma_map_single(dev->dma_dev, iter->data, iter->len,
 				      DMA_TO_DEVICE);
-		if (unlikely(dma_mapping_error(dev->dma_dev, addr)))
+		if (unlikely(dma_mapping_error(dev->dma_dev, addr))) {
+			reason = MT_TX_DROP_DMA_FAIL;
 			goto unmap;
+		}
 
 		tx_info.buf[n].addr = addr;
 		tx_info.buf[n++].len = iter->len;
@@ -652,6 +663,7 @@ mt76_dma_tx_queue_skb(struct mt76_phy *phy, struct mt76_queue *q,
 
 	if (q->queued + (tx_info.nbuf + 1) / 2 >= q->ndesc - 1) {
 		ret = -ENOMEM;
+		reason = MT_TX_DROP_RING_FULL;
 		goto unmap;
 	}
 
@@ -663,6 +675,7 @@ mt76_dma_tx_queue_skb(struct mt76_phy *phy, struct mt76_queue *q,
 	if (ret < 0)
 		goto unmap;
 
+	phy->tx_dbg_stats.tx_to_hw++;
 	return mt76_dma_add_buf(dev, q, tx_info.buf, tx_info.nbuf,
 				tx_info.info, tx_info.skb, t, NULL);
 
@@ -690,6 +703,9 @@ free_skb:
 	ieee80211_tx_status_ext(hw, &status);
 	spin_unlock_bh(&dev->rx_lock);
 
+	if (reason >= 0)
+		phy->tx_dbg_stats.tx_drop[reason]++;
+
 	return ret;
 }
 
diff --git a/mt76.h b/mt76.h
index b6292e3..c1128d1 100644
--- a/mt76.h
+++ b/mt76.h
@@ -849,6 +849,27 @@ struct mt76_vif {
 	struct ieee80211_chanctx_conf *ctx;
 };
 
+enum {
+	MT_TX_DROP_IN_TESTMODE,
+	MT_TX_DROP_WCID_NOT_INIT,
+	MT_TX_DROP_STOPPED_QUEUE,
+	MT_TX_DROP_RESET_STATE,
+	MT_TX_DROP_GET_TXWI_FAIL,
+	MT_TX_DROP_DMA_FAIL,
+	MT_TX_DROP_AGG_EXCEEDED,
+	MT_TX_DROP_RING_FULL,
+	MT_TX_DROP_INVALID_SKB,
+	MT_TX_DROP_GET_TOKEN_FAIL,
+	MT_TX_DROP_MAX,
+};
+
+struct mt76_tx_debug {
+	u32 tx_from_mac80211;
+	u32 tx_to_hw;
+
+	u32 tx_drop[MT_TX_DROP_MAX];
+};
+
 struct mt76_phy {
 	struct ieee80211_hw *hw;
 	struct mt76_dev *dev;
@@ -906,6 +927,7 @@ struct mt76_phy {
 		u8 pin;
 	} leds;
 	int tokens;
+	struct mt76_tx_debug tx_dbg_stats;
 };
 
 struct mt76_dev {
diff --git a/mt7915/mac.c b/mt7915/mac.c
index 0c12170..1e2ef8c 100644
--- a/mt7915/mac.c
+++ b/mt7915/mac.c
@@ -782,9 +782,15 @@ int mt7915_tx_prepare_skb(struct mt76_dev *mdev, void *txwi_ptr,
 	u8 phy_idx = (info->hw_queue & MT_TX_HW_QUEUE_PHY) >> 2;
 	u8 *txwi = (u8 *)txwi_ptr;
 	int pid;
+	struct mt76_phy *mphy = &mdev->phy;
 
-	if (unlikely(tx_info->skb->len <= ETH_HLEN))
+	if (phy_idx && mdev->phys[MT_BAND1])
+		mphy = mdev->phys[MT_BAND1];
+
+	if (unlikely(tx_info->skb->len <= ETH_HLEN)) {
+		mphy->tx_dbg_stats.tx_drop[MT_TX_DROP_INVALID_SKB]++;
 		return -EINVAL;
+	}
 
 	if (!wcid)
 		wcid = &dev->mt76.global_wcid;
@@ -804,12 +810,16 @@ int mt7915_tx_prepare_skb(struct mt76_dev *mdev, void *txwi_ptr,
 	t->skb = tx_info->skb;
 
 	if (ieee80211_is_action(fc) &&
-	    mgmt->u.action.category == 0xff)
+	    mgmt->u.action.category == 0xff) {
+		mphy->tx_dbg_stats.tx_drop[MT_TX_DROP_INVALID_SKB]++;
 		return -1;
+	}
 
 	id = mt76_token_consume(mdev, &t, phy_idx);
-	if (id < 0)
+	if (id < 0) {
+		mphy->tx_dbg_stats.tx_drop[MT_TX_DROP_GET_TOKEN_FAIL]++;
 		return id;
+	}
 
 	t->jiffies = jiffies;
 
diff --git a/mt7915/mtk_debugfs.c b/mt7915/mtk_debugfs.c
index 129a4dd..568ecff 100644
--- a/mt7915/mtk_debugfs.c
+++ b/mt7915/mtk_debugfs.c
@@ -4033,6 +4033,12 @@ static int mt7915_reset_counter(void *data, u64 val)
 	struct mt7915_dev *dev = phy->dev;
 	struct mt76_wcid *wcid;
 
+	if (!dev->wlan_idx) {
+		memset(&phy->mt76->tx_dbg_stats, 0, sizeof(struct mt76_tx_debug));
+
+		return 0;
+	}
+
 	/* Clear the firmware counters */
 	mt7915_mcu_wed_wa_tx_stats(dev, dev->wlan_idx, NULL);
 	mt7915_get_tx_stat(phy, dev->wlan_idx);
@@ -4087,6 +4093,35 @@ mt7915_per_read(struct seq_file *s, void *data)
 	return 0;
 }
 
+static int
+mt7915_tx_drop_show(struct seq_file *s, void *data)
+{
+	struct mt7915_phy *phy = s->private;
+	struct mt76_tx_debug *stats = &phy->mt76->tx_dbg_stats;
+
+	seq_printf(s, "Receive from mac80211: %d\n", stats->tx_from_mac80211);
+	seq_printf(s, "Send to hw: %d\n", stats->tx_to_hw);
+
+#define __pr(t) seq_printf(s, "Drop due to %s: %d\n", \
+			   #t, stats->tx_drop[MT_TX_DROP_##t])
+	__pr(IN_TESTMODE);
+	__pr(WCID_NOT_INIT);
+	__pr(STOPPED_QUEUE);
+	__pr(RESET_STATE);
+	__pr(GET_TXWI_FAIL);
+	__pr(DMA_FAIL);
+	__pr(AGG_EXCEEDED);
+	__pr(RING_FULL);
+	__pr(INVALID_SKB);
+	__pr(GET_TOKEN_FAIL);
+
+#undef __pr
+
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(mt7915_tx_drop);
+
 int mt7915_mtk_init_debugfs(struct mt7915_phy *phy, struct dentry *dir)
 {
 	struct mt7915_dev *dev = phy->dev;
@@ -4186,7 +4221,9 @@ int mt7915_mtk_init_debugfs(struct mt7915_phy *phy, struct dentry *dir)
 	debugfs_create_file("sr_scene_cond", 0400, dir, phy, &mt7915_sr_scene_cond_fops);
 	debugfs_create_file("reset_counter", 0200, dir, phy, &fops_reset_counter);
 	debugfs_create_devm_seqfile(dev->mt76.dev, "per", dir, mt7915_per_read);
+	debugfs_create_file("tx_drop_stats", 0400, dir, phy, &mt7915_tx_drop_fops);
 
 	return 0;
 }
+
 #endif
diff --git a/tx.c b/tx.c
index df2bb07..e4eb74b 100644
--- a/tx.c
+++ b/tx.c
@@ -330,8 +330,10 @@ mt76_tx(struct mt76_phy *phy, struct ieee80211_sta *sta,
 {
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 
+	phy->tx_dbg_stats.tx_from_mac80211++;
 	if (mt76_testmode_enabled(phy)) {
 		ieee80211_free_txskb(phy->hw, skb);
+		phy->tx_dbg_stats.tx_drop[MT_TX_DROP_IN_TESTMODE]++;
 		return;
 	}
 
@@ -348,6 +350,7 @@ mt76_tx(struct mt76_phy *phy, struct ieee80211_sta *sta,
 		dev_warn(phy->dev->dev, "Un-initialized STA %pM wcid %d in mt76_tx\n",
 			 sta->addr, wcid->idx);
 
+		phy->tx_dbg_stats.tx_drop[MT_TX_DROP_WCID_NOT_INIT]++;
 		ieee80211_free_txskb(phy->hw, skb);
 		return;
 	}
@@ -379,6 +382,8 @@ mt76_txq_dequeue(struct mt76_phy *phy, struct mt76_txq *mtxq)
 	info = IEEE80211_SKB_CB(skb);
 	info->hw_queue |= FIELD_PREP(MT_TX_HW_QUEUE_PHY, phy->band_idx);
 
+	phy->tx_dbg_stats.tx_from_mac80211++;
+
 	return skb;
 }
 
@@ -616,6 +621,7 @@ mt76_txq_schedule_pending_wcid(struct mt76_phy *phy, struct mt76_wcid *wcid)
 		q = phy->q_tx[qid];
 		if (mt76_txq_stopped(q)) {
 			ret = -1;
+			phy->tx_dbg_stats.tx_drop[MT_TX_DROP_STOPPED_QUEUE]++;
 			break;
 		}
 
-- 
2.18.0