[PATCH v3] ath10k: implement NAPI support

[Rajkumar Manoharan <rmanohar@qti.qualcomm.com>]

Add NAPI support for rx and tx completion. NAPI poll is scheduled
from interrupt handler. The design is as below

 - on interrupt
     - schedule napi and mask interrupts
 - on poll
   - process all pipes (no actual Tx/Rx)
   - process Rx within budget
   - if quota exceeds budget reschedule napi poll by returning budget
   - process Tx completions and update budget if necessary
   - process Tx fetch indications (pull-push)
   - push any other pending Tx (if possible)
   - before resched or napi completion replenish htt rx ring buffer
   - if work done < budget, complete napi poll and unmask interrupts

This change also get rid of two tasklets (intr_tq and txrx_compl_task).

Measured peak throughput with NAPI on IPQ4019 platform in controlled
environment. No noticeable reduction in throughput is seen and also
observed improvements in CPU usage. Approx. 15% CPU usage got reduced
in UDP uplink case.

DL: AP DUT Tx
UL: AP DUT Rx

IPQ4019 (avg. cpu usage %)
========
                TOT              +NAPI
              ===========      =============
TCP DL       644 Mbps (42%)    645 Mbps (36%)
TCP UL       673 Mbps (30%)    675 Mbps (26%)
UDP DL       682 Mbps (49%)    680 Mbps (49%)
UDP UL       720 Mbps (28%)    717 Mbps (11%)

Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
---
v2: rebased change
v3: napi_synchronize and napi_disable should be called on deinit. Otherwise
    it is causing invalid memory access. Thanks to Kalle for reporting this issue.

 drivers/net/wireless/ath/ath10k/ahb.c    |  10 +-
 drivers/net/wireless/ath/ath10k/core.c   |   2 +
 drivers/net/wireless/ath/ath10k/core.h   |   8 ++
 drivers/net/wireless/ath/ath10k/htt.h    |   2 +-
 drivers/net/wireless/ath/ath10k/htt_rx.c | 154 +++++++++++++++++++------------
 drivers/net/wireless/ath/ath10k/htt_tx.c |   2 -
 drivers/net/wireless/ath/ath10k/pci.c    |  71 ++++++++------
 drivers/net/wireless/ath/ath10k/pci.h    |   6 +-
 8 files changed, 159 insertions(+), 96 deletions(-)

diff --git a/drivers/net/wireless/ath/ath10k/ahb.c b/drivers/net/wireless/ath/ath10k/ahb.c
index acec16b9cf49..83ecfb6d1a36 100644
--- a/drivers/net/wireless/ath/ath10k/ahb.c
+++ b/drivers/net/wireless/ath/ath10k/ahb.c
@@ -462,13 +462,13 @@ static void ath10k_ahb_halt_chip(struct ath10k *ar)
 static irqreturn_t ath10k_ahb_interrupt_handler(int irq, void *arg)
 {
 	struct ath10k *ar = arg;
-	struct ath10k_pci *ar_pci = ath10k_pci_priv(ar);
 
 	if (!ath10k_pci_irq_pending(ar))
 		return IRQ_NONE;
 
 	ath10k_pci_disable_and_clear_legacy_irq(ar);
-	tasklet_schedule(&ar_pci->intr_tq);
+	ath10k_pci_irq_msi_fw_mask(ar);
+	napi_schedule(&ar->napi);
 
 	return IRQ_HANDLED;
 }
@@ -717,6 +717,9 @@ static void ath10k_ahb_hif_stop(struct ath10k *ar)
 	synchronize_irq(ar_ahb->irq);
 
 	ath10k_pci_flush(ar);
+
+	napi_synchronize(&ar->napi);
+	napi_disable(&ar->napi);
 }
 
 static int ath10k_ahb_hif_power_up(struct ath10k *ar)
@@ -748,6 +751,7 @@ static int ath10k_ahb_hif_power_up(struct ath10k *ar)
 		ath10k_err(ar, "could not wake up target CPU: %d\n", ret);
 		goto err_ce_deinit;
 	}
+	napi_enable(&ar->napi);
 
 	return 0;
 
@@ -831,7 +835,7 @@ static int ath10k_ahb_probe(struct platform_device *pdev)
 		goto err_resource_deinit;
 	}
 
-	ath10k_pci_init_irq_tasklets(ar);
+	ath10k_pci_init_napi(ar);
 
 	ret = ath10k_ahb_request_irq_legacy(ar);
 	if (ret)
diff --git a/drivers/net/wireless/ath/ath10k/core.c b/drivers/net/wireless/ath/ath10k/core.c
index e88982921aa3..0ca58cf0ffea 100644
--- a/drivers/net/wireless/ath/ath10k/core.c
+++ b/drivers/net/wireless/ath/ath10k/core.c
@@ -2249,6 +2249,8 @@ struct ath10k *ath10k_core_create(size_t priv_size, struct device *dev,
 	INIT_WORK(&ar->register_work, ath10k_core_register_work);
 	INIT_WORK(&ar->restart_work, ath10k_core_restart);
 
+	init_dummy_netdev(&ar->napi_dev);
+
 	ret = ath10k_debug_create(ar);
 	if (ret)
 		goto err_free_aux_wq;
diff --git a/drivers/net/wireless/ath/ath10k/core.h b/drivers/net/wireless/ath/ath10k/core.h
index 30ae5bf81611..f36c2b274ee5 100644
--- a/drivers/net/wireless/ath/ath10k/core.h
+++ b/drivers/net/wireless/ath/ath10k/core.h
@@ -65,6 +65,10 @@
 #define ATH10K_KEEPALIVE_MAX_IDLE 3895
 #define ATH10K_KEEPALIVE_MAX_UNRESPONSIVE 3900
 
+/* NAPI poll budget */
+#define ATH10K_NAPI_BUDGET      64
+#define ATH10K_NAPI_QUOTA_LIMIT 60
+
 struct ath10k;
 
 enum ath10k_bus {
@@ -936,6 +940,10 @@ struct ath10k {
 	struct ath10k_thermal thermal;
 	struct ath10k_wow wow;
 
+	/* NAPI */
+	struct net_device napi_dev;
+	struct napi_struct napi;
+
 	/* must be last */
 	u8 drv_priv[0] __aligned(sizeof(void *));
 };
diff --git a/drivers/net/wireless/ath/ath10k/htt.h b/drivers/net/wireless/ath/ath10k/htt.h
index 430a83e142aa..98c14247021b 100644
--- a/drivers/net/wireless/ath/ath10k/htt.h
+++ b/drivers/net/wireless/ath/ath10k/htt.h
@@ -1665,7 +1665,6 @@ struct ath10k_htt {
 
 	/* This is used to group tx/rx completions separately and process them
 	 * in batches to reduce cache stalls */
-	struct tasklet_struct txrx_compl_task;
 	struct sk_buff_head rx_compl_q;
 	struct sk_buff_head rx_in_ord_compl_q;
 	struct sk_buff_head tx_fetch_ind_q;
@@ -1798,5 +1797,6 @@ int ath10k_htt_tx(struct ath10k_htt *htt,
 		  struct sk_buff *msdu);
 void ath10k_htt_rx_pktlog_completion_handler(struct ath10k *ar,
 					     struct sk_buff *skb);
+int ath10k_htt_txrx_compl_task(struct ath10k *ar, int budget);
 
 #endif
diff --git a/drivers/net/wireless/ath/ath10k/htt_rx.c b/drivers/net/wireless/ath/ath10k/htt_rx.c
index 78db5d679f19..d3f8baf532d4 100644
--- a/drivers/net/wireless/ath/ath10k/htt_rx.c
+++ b/drivers/net/wireless/ath/ath10k/htt_rx.c
@@ -34,7 +34,6 @@
 #define HTT_RX_RING_REFILL_RESCHED_MS 5
 
 static int ath10k_htt_rx_get_csum_state(struct sk_buff *skb);
-static void ath10k_htt_txrx_compl_task(unsigned long ptr);
 
 static struct sk_buff *
 ath10k_htt_rx_find_skb_paddr(struct ath10k *ar, u32 paddr)
@@ -226,7 +225,6 @@ int ath10k_htt_rx_ring_refill(struct ath10k *ar)
 void ath10k_htt_rx_free(struct ath10k_htt *htt)
 {
 	del_timer_sync(&htt->rx_ring.refill_retry_timer);
-	tasklet_kill(&htt->txrx_compl_task);
 
 	skb_queue_purge(&htt->rx_compl_q);
 	skb_queue_purge(&htt->rx_in_ord_compl_q);
@@ -520,9 +518,6 @@ int ath10k_htt_rx_alloc(struct ath10k_htt *htt)
 	skb_queue_head_init(&htt->tx_fetch_ind_q);
 	atomic_set(&htt->num_mpdus_ready, 0);
 
-	tasklet_init(&htt->txrx_compl_task, ath10k_htt_txrx_compl_task,
-		     (unsigned long)htt);
-
 	ath10k_dbg(ar, ATH10K_DBG_BOOT, "htt rx ring size %d fill_level %d\n",
 		   htt->rx_ring.size, htt->rx_ring.fill_level);
 	return 0;
@@ -958,7 +953,7 @@ static void ath10k_process_rx(struct ath10k *ar,
 	trace_ath10k_rx_hdr(ar, skb->data, skb->len);
 	trace_ath10k_rx_payload(ar, skb->data, skb->len);
 
-	ieee80211_rx(ar->hw, skb);
+	ieee80211_rx_napi(ar->hw, NULL, skb, &ar->napi);
 }
 
 static int ath10k_htt_rx_nwifi_hdrlen(struct ath10k *ar,
@@ -1527,7 +1522,7 @@ static int ath10k_htt_rx_handle_amsdu(struct ath10k_htt *htt)
 	struct ath10k *ar = htt->ar;
 	static struct ieee80211_rx_status rx_status;
 	struct sk_buff_head amsdu;
-	int ret;
+	int ret, num_msdus;
 
 	__skb_queue_head_init(&amsdu);
 
@@ -1549,13 +1544,14 @@ static int ath10k_htt_rx_handle_amsdu(struct ath10k_htt *htt)
 		return ret;
 	}
 
+	num_msdus = skb_queue_len(&amsdu);
 	ath10k_htt_rx_h_ppdu(ar, &amsdu, &rx_status, 0xffff);
 	ath10k_htt_rx_h_unchain(ar, &amsdu, ret > 0);
 	ath10k_htt_rx_h_filter(ar, &amsdu, &rx_status);
 	ath10k_htt_rx_h_mpdu(ar, &amsdu, &rx_status);
 	ath10k_htt_rx_h_deliver(ar, &amsdu, &rx_status);
 
-	return 0;
+	return num_msdus;
 }
 
 static void ath10k_htt_rx_proc_rx_ind(struct ath10k_htt *htt,
@@ -1579,15 +1575,6 @@ static void ath10k_htt_rx_proc_rx_ind(struct ath10k_htt *htt,
 		mpdu_count += mpdu_ranges[i].mpdu_count;
 
 	atomic_add(mpdu_count, &htt->num_mpdus_ready);
-
-	tasklet_schedule(&htt->txrx_compl_task);
-}
-
-static void ath10k_htt_rx_frag_handler(struct ath10k_htt *htt)
-{
-	atomic_inc(&htt->num_mpdus_ready);
-
-	tasklet_schedule(&htt->txrx_compl_task);
 }
 
 static void ath10k_htt_rx_tx_compl_ind(struct ath10k *ar,
@@ -1772,14 +1759,15 @@ static void ath10k_htt_rx_h_rx_offload_prot(struct ieee80211_rx_status *status,
 			RX_FLAG_MMIC_STRIPPED;
 }
 
-static void ath10k_htt_rx_h_rx_offload(struct ath10k *ar,
-				       struct sk_buff_head *list)
+static int ath10k_htt_rx_h_rx_offload(struct ath10k *ar,
+				      struct sk_buff_head *list)
 {
 	struct ath10k_htt *htt = &ar->htt;
 	struct ieee80211_rx_status *status = &htt->rx_status;
 	struct htt_rx_offload_msdu *rx;
 	struct sk_buff *msdu;
 	size_t offset;
+	int num_msdu = 0;
 
 	while ((msdu = __skb_dequeue(list))) {
 		/* Offloaded frames don't have Rx descriptor. Instead they have
@@ -1819,10 +1807,12 @@ static void ath10k_htt_rx_h_rx_offload(struct ath10k *ar,
 		ath10k_htt_rx_h_rx_offload_prot(status, msdu);
 		ath10k_htt_rx_h_channel(ar, status, NULL, rx->vdev_id);
 		ath10k_process_rx(ar, status, msdu);
+		num_msdu++;
 	}
+	return num_msdu;
 }
 
-static void ath10k_htt_rx_in_ord_ind(struct ath10k *ar, struct sk_buff *skb)
+static int ath10k_htt_rx_in_ord_ind(struct ath10k *ar, struct sk_buff *skb)
 {
 	struct ath10k_htt *htt = &ar->htt;
 	struct htt_resp *resp = (void *)skb->data;
@@ -1835,12 +1825,12 @@ static void ath10k_htt_rx_in_ord_ind(struct ath10k *ar, struct sk_buff *skb)
 	u8 tid;
 	bool offload;
 	bool frag;
-	int ret;
+	int ret, num_msdus = 0;
 
 	lockdep_assert_held(&htt->rx_ring.lock);
 
 	if (htt->rx_confused)
-		return;
+		return -EIO;
 
 	skb_pull(skb, sizeof(resp->hdr));
 	skb_pull(skb, sizeof(resp->rx_in_ord_ind));
@@ -1859,7 +1849,7 @@ static void ath10k_htt_rx_in_ord_ind(struct ath10k *ar, struct sk_buff *skb)
 
 	if (skb->len < msdu_count * sizeof(*resp->rx_in_ord_ind.msdu_descs)) {
 		ath10k_warn(ar, "dropping invalid in order rx indication\n");
-		return;
+		return -EINVAL;
 	}
 
 	/* The event can deliver more than 1 A-MSDU. Each A-MSDU is later
@@ -1870,14 +1860,14 @@ static void ath10k_htt_rx_in_ord_ind(struct ath10k *ar, struct sk_buff *skb)
 	if (ret < 0) {
 		ath10k_warn(ar, "failed to pop paddr list: %d\n", ret);
 		htt->rx_confused = true;
-		return;
+		return -EIO;
 	}
 
 	/* Offloaded frames are very different and need to be handled
 	 * separately.
 	 */
 	if (offload)
-		ath10k_htt_rx_h_rx_offload(ar, &list);
+		num_msdus = ath10k_htt_rx_h_rx_offload(ar, &list);
 
 	while (!skb_queue_empty(&list)) {
 		__skb_queue_head_init(&amsdu);
@@ -1890,6 +1880,7 @@ static void ath10k_htt_rx_in_ord_ind(struct ath10k *ar, struct sk_buff *skb)
 			 * better to report something than nothing though. This
 			 * should still give an idea about rx rate to the user.
 			 */
+			num_msdus += skb_queue_len(&amsdu);
 			ath10k_htt_rx_h_ppdu(ar, &amsdu, status, vdev_id);
 			ath10k_htt_rx_h_filter(ar, &amsdu, status);
 			ath10k_htt_rx_h_mpdu(ar, &amsdu, status);
@@ -1902,9 +1893,10 @@ static void ath10k_htt_rx_in_ord_ind(struct ath10k *ar, struct sk_buff *skb)
 			ath10k_warn(ar, "failed to extract amsdu: %d\n", ret);
 			htt->rx_confused = true;
 			__skb_queue_purge(&list);
-			return;
+			return -EIO;
 		}
 	}
+	return num_msdus;
 }
 
 static void ath10k_htt_rx_tx_fetch_resp_id_confirm(struct ath10k *ar,
@@ -2267,7 +2259,6 @@ bool ath10k_htt_t2h_msg_handler(struct ath10k *ar, struct sk_buff *skb)
 	}
 	case HTT_T2H_MSG_TYPE_TX_COMPL_IND:
 		ath10k_htt_rx_tx_compl_ind(htt->ar, skb);
-		tasklet_schedule(&htt->txrx_compl_task);
 		break;
 	case HTT_T2H_MSG_TYPE_SEC_IND: {
 		struct ath10k *ar = htt->ar;
@@ -2284,7 +2275,7 @@ bool ath10k_htt_t2h_msg_handler(struct ath10k *ar, struct sk_buff *skb)
 	case HTT_T2H_MSG_TYPE_RX_FRAG_IND: {
 		ath10k_dbg_dump(ar, ATH10K_DBG_HTT_DUMP, NULL, "htt event: ",
 				skb->data, skb->len);
-		ath10k_htt_rx_frag_handler(htt);
+		atomic_inc(&htt->num_mpdus_ready);
 		break;
 	}
 	case HTT_T2H_MSG_TYPE_TEST:
@@ -2320,8 +2311,7 @@ bool ath10k_htt_t2h_msg_handler(struct ath10k *ar, struct sk_buff *skb)
 		break;
 	}
 	case HTT_T2H_MSG_TYPE_RX_IN_ORD_PADDR_IND: {
-		skb_queue_tail(&htt->rx_in_ord_compl_q, skb);
-		tasklet_schedule(&htt->txrx_compl_task);
+		__skb_queue_tail(&htt->rx_in_ord_compl_q, skb);
 		return false;
 	}
 	case HTT_T2H_MSG_TYPE_TX_CREDIT_UPDATE_IND:
@@ -2347,7 +2337,6 @@ bool ath10k_htt_t2h_msg_handler(struct ath10k *ar, struct sk_buff *skb)
 			break;
 		}
 		skb_queue_tail(&htt->tx_fetch_ind_q, tx_fetch_ind);
-		tasklet_schedule(&htt->txrx_compl_task);
 		break;
 	}
 	case HTT_T2H_MSG_TYPE_TX_FETCH_CONFIRM:
@@ -2376,27 +2365,77 @@ void ath10k_htt_rx_pktlog_completion_handler(struct ath10k *ar,
 }
 EXPORT_SYMBOL(ath10k_htt_rx_pktlog_completion_handler);
 
-static void ath10k_htt_txrx_compl_task(unsigned long ptr)
+int ath10k_htt_txrx_compl_task(struct ath10k *ar, int budget)
 {
-	struct ath10k_htt *htt = (struct ath10k_htt *)ptr;
-	struct ath10k *ar = htt->ar;
+	struct ath10k_htt *htt = &ar->htt;
 	struct htt_tx_done tx_done = {};
-	struct sk_buff_head rx_ind_q;
 	struct sk_buff_head tx_ind_q;
 	struct sk_buff *skb;
 	unsigned long flags;
-	int num_mpdus;
+	int quota = 0, done, num_rx_msdus;
+	bool resched_napi = false;
 
-	__skb_queue_head_init(&rx_ind_q);
 	__skb_queue_head_init(&tx_ind_q);
 
-	spin_lock_irqsave(&htt->rx_in_ord_compl_q.lock, flags);
-	skb_queue_splice_init(&htt->rx_in_ord_compl_q, &rx_ind_q);
-	spin_unlock_irqrestore(&htt->rx_in_ord_compl_q.lock, flags);
+	/* Since in-ord-ind can deliver more than 1 A-MSDU in single event,
+	 * process it first to utilize full available quota.
+	 */
+	while (quota < budget) {
+		if (skb_queue_empty(&htt->rx_in_ord_compl_q))
+			break;
 
-	spin_lock_irqsave(&htt->tx_fetch_ind_q.lock, flags);
-	skb_queue_splice_init(&htt->tx_fetch_ind_q, &tx_ind_q);
-	spin_unlock_irqrestore(&htt->tx_fetch_ind_q.lock, flags);
+		skb = __skb_dequeue(&htt->rx_in_ord_compl_q);
+		if (!skb) {
+			resched_napi = true;
+			goto exit;
+		}
+
+		spin_lock_bh(&htt->rx_ring.lock);
+		num_rx_msdus = ath10k_htt_rx_in_ord_ind(ar, skb);
+		spin_unlock_bh(&htt->rx_ring.lock);
+		if (num_rx_msdus < 0) {
+			resched_napi = true;
+			goto exit;
+		}
+
+		dev_kfree_skb_any(skb);
+		if (num_rx_msdus > 0)
+			quota += num_rx_msdus;
+
+		if ((quota > ATH10K_NAPI_QUOTA_LIMIT) &&
+		    !skb_queue_empty(&htt->rx_in_ord_compl_q)) {
+			resched_napi = true;
+			goto exit;
+		}
+	}
+
+	while (quota < budget) {
+		/* no more data to receive */
+		if (!atomic_read(&htt->num_mpdus_ready))
+			break;
+
+		num_rx_msdus = ath10k_htt_rx_handle_amsdu(htt);
+		if (num_rx_msdus < 0) {
+			resched_napi = true;
+			goto exit;
+		}
+
+		quota += num_rx_msdus;
+		atomic_dec(&htt->num_mpdus_ready);
+		if ((quota > ATH10K_NAPI_QUOTA_LIMIT) &&
+		    atomic_read(&htt->num_mpdus_ready)) {
+			resched_napi = true;
+			goto exit;
+		}
+	}
+
+	/* From NAPI documentation:
+	 *  The napi poll() function may also process TX completions, in which
+	 *  case if it processes the entire TX ring then it should count that
+	 *  work as the rest of the budget.
+	 */
+	if ((quota < budget) && !kfifo_is_empty(&htt->txdone_fifo))
+		quota = budget;
 
 	/* kfifo_get: called only within txrx_tasklet so it's neatly serialized.
 	 * From kfifo_get() documentation:
@@ -2406,27 +2445,22 @@ static void ath10k_htt_txrx_compl_task(unsigned long ptr)
 	while (kfifo_get(&htt->txdone_fifo, &tx_done))
 		ath10k_txrx_tx_unref(htt, &tx_done);
 
+	spin_lock_irqsave(&htt->tx_fetch_ind_q.lock, flags);
+	skb_queue_splice_init(&htt->tx_fetch_ind_q, &tx_ind_q);
+	spin_unlock_irqrestore(&htt->tx_fetch_ind_q.lock, flags);
+
 	while ((skb = __skb_dequeue(&tx_ind_q))) {
 		ath10k_htt_rx_tx_fetch_ind(ar, skb);
 		dev_kfree_skb_any(skb);
 	}
 
-	num_mpdus = atomic_read(&htt->num_mpdus_ready);
-
-	while (num_mpdus) {
-		if (ath10k_htt_rx_handle_amsdu(htt))
-			break;
-
-		num_mpdus--;
-		atomic_dec(&htt->num_mpdus_ready);
-	}
-
-	while ((skb = __skb_dequeue(&rx_ind_q))) {
-		spin_lock_bh(&htt->rx_ring.lock);
-		ath10k_htt_rx_in_ord_ind(ar, skb);
-		spin_unlock_bh(&htt->rx_ring.lock);
-		dev_kfree_skb_any(skb);
-	}
-
+exit:
 	ath10k_htt_rx_msdu_buff_replenish(htt);
+	/* In case of rx failure or more data to read, report budget
+	 * to reschedule NAPI poll
+	 */
+	done = resched_napi ? budget : quota;
+
+	return done;
 }
+EXPORT_SYMBOL(ath10k_htt_txrx_compl_task);
diff --git a/drivers/net/wireless/ath/ath10k/htt_tx.c b/drivers/net/wireless/ath/ath10k/htt_tx.c
index 7c072b605bc7..ae5b33fe5ba8 100644
--- a/drivers/net/wireless/ath/ath10k/htt_tx.c
+++ b/drivers/net/wireless/ath/ath10k/htt_tx.c
@@ -390,8 +390,6 @@ void ath10k_htt_tx_free(struct ath10k_htt *htt)
 {
 	int size;
 
-	tasklet_kill(&htt->txrx_compl_task);
-
 	idr_for_each(&htt->pending_tx, ath10k_htt_tx_clean_up_pending, htt->ar);
 	idr_destroy(&htt->pending_tx);
 
diff --git a/drivers/net/wireless/ath/ath10k/pci.c b/drivers/net/wireless/ath/ath10k/pci.c
index 9a22c478dd1b..4bc663979856 100644
--- a/drivers/net/wireless/ath/ath10k/pci.c
+++ b/drivers/net/wireless/ath/ath10k/pci.c
@@ -1506,12 +1506,10 @@ void ath10k_pci_hif_send_complete_check(struct ath10k *ar, u8 pipe,
 	ath10k_ce_per_engine_service(ar, pipe);
 }
 
-void ath10k_pci_kill_tasklet(struct ath10k *ar)
+static void ath10k_pci_rx_retry_sync(struct ath10k *ar)
 {
 	struct ath10k_pci *ar_pci = ath10k_pci_priv(ar);
 
-	tasklet_kill(&ar_pci->intr_tq);
-
 	del_timer_sync(&ar_pci->rx_post_retry);
 }
 
@@ -1570,7 +1568,7 @@ void ath10k_pci_hif_get_default_pipe(struct ath10k *ar,
 						 ul_pipe, dl_pipe);
 }
 
-static void ath10k_pci_irq_msi_fw_mask(struct ath10k *ar)
+void ath10k_pci_irq_msi_fw_mask(struct ath10k *ar)
 {
 	u32 val;
 
@@ -1753,7 +1751,7 @@ void ath10k_pci_ce_deinit(struct ath10k *ar)
 
 void ath10k_pci_flush(struct ath10k *ar)
 {
-	ath10k_pci_kill_tasklet(ar);
+	ath10k_pci_rx_retry_sync(ar);
 	ath10k_pci_buffer_cleanup(ar);
 }
 
@@ -1780,6 +1778,8 @@ static void ath10k_pci_hif_stop(struct ath10k *ar)
 	ath10k_pci_irq_disable(ar);
 	ath10k_pci_irq_sync(ar);
 	ath10k_pci_flush(ar);
+	napi_synchronize(&ar->napi);
+	napi_disable(&ar->napi);
 
 	spin_lock_irqsave(&ar_pci->ps_lock, flags);
 	WARN_ON(ar_pci->ps_wake_refcount > 0);
@@ -2533,6 +2533,7 @@ static int ath10k_pci_hif_power_up(struct ath10k *ar)
 		ath10k_err(ar, "could not wake up target CPU: %d\n", ret);
 		goto err_ce;
 	}
+	napi_enable(&ar->napi);
 
 	return 0;
 
@@ -2772,35 +2773,53 @@ static irqreturn_t ath10k_pci_interrupt_handler(int irq, void *arg)
 		return IRQ_NONE;
 	}
 
-	if (ar_pci->oper_irq_mode == ATH10K_PCI_IRQ_LEGACY) {
-		if (!ath10k_pci_irq_pending(ar))
-			return IRQ_NONE;
-
-		ath10k_pci_disable_and_clear_legacy_irq(ar);
-	}
+	if ((ar_pci->oper_irq_mode == ATH10K_PCI_IRQ_LEGACY) &&
+	    !ath10k_pci_irq_pending(ar))
+		return IRQ_NONE;
 
-	tasklet_schedule(&ar_pci->intr_tq);
+	ath10k_pci_disable_and_clear_legacy_irq(ar);
+	ath10k_pci_irq_msi_fw_mask(ar);
+	napi_schedule(&ar->napi);
 
 	return IRQ_HANDLED;
 }
 
-static void ath10k_pci_tasklet(unsigned long data)
+static int ath10k_pci_napi_poll(struct napi_struct *ctx, int budget)
 {
-	struct ath10k *ar = (struct ath10k *)data;
-	struct ath10k_pci *ar_pci = ath10k_pci_priv(ar);
+	struct ath10k *ar = container_of(ctx, struct ath10k, napi);
+	int done = 0;
 
 	if (ath10k_pci_has_fw_crashed(ar)) {
-		ath10k_pci_irq_disable(ar);
 		ath10k_pci_fw_crashed_clear(ar);
 		ath10k_pci_fw_crashed_dump(ar);
-		return;
+		napi_complete(ctx);
+		return done;
 	}
 
 	ath10k_ce_per_engine_service_any(ar);
 
-	/* Re-enable legacy irq that was disabled in the irq handler */
-	if (ar_pci->oper_irq_mode == ATH10K_PCI_IRQ_LEGACY)
+	done = ath10k_htt_txrx_compl_task(ar, budget);
+
+	if (done < budget) {
+		napi_complete(ctx);
+		/* In case of MSI, it is possible that interrupts are received
+		 * while NAPI poll is inprogress. So pending interrupts that are
+		 * received after processing all copy engine pipes by NAPI poll
+		 * will not be handled again. This is causing failure to
+		 * complete boot sequence in x86 platform. So before enabling
+		 * interrupts safer to check for pending interrupts for
+		 * immediate servicing.
+		 */
+		if (CE_INTERRUPT_SUMMARY(ar)) {
+			napi_reschedule(ctx);
+			goto out;
+		}
 		ath10k_pci_enable_legacy_irq(ar);
+		ath10k_pci_irq_msi_fw_unmask(ar);
+	}
+
+out:
+	return done;
 }
 
 static int ath10k_pci_request_irq_msi(struct ath10k *ar)
@@ -2858,11 +2877,10 @@ static void ath10k_pci_free_irq(struct ath10k *ar)
 	free_irq(ar_pci->pdev->irq, ar);
 }
 
-void ath10k_pci_init_irq_tasklets(struct ath10k *ar)
+void ath10k_pci_init_napi(struct ath10k *ar)
 {
-	struct ath10k_pci *ar_pci = ath10k_pci_priv(ar);
-
-	tasklet_init(&ar_pci->intr_tq, ath10k_pci_tasklet, (unsigned long)ar);
+	netif_napi_add(&ar->napi_dev, &ar->napi, ath10k_pci_napi_poll,
+		       ATH10K_NAPI_BUDGET);
 }
 
 static int ath10k_pci_init_irq(struct ath10k *ar)
@@ -2870,7 +2888,7 @@ static int ath10k_pci_init_irq(struct ath10k *ar)
 	struct ath10k_pci *ar_pci = ath10k_pci_priv(ar);
 	int ret;
 
-	ath10k_pci_init_irq_tasklets(ar);
+	ath10k_pci_init_napi(ar);
 
 	if (ath10k_pci_irq_mode != ATH10K_PCI_IRQ_AUTO)
 		ath10k_info(ar, "limiting irq mode to: %d\n",
@@ -3131,7 +3149,8 @@ int ath10k_pci_setup_resource(struct ath10k *ar)
 
 void ath10k_pci_release_resource(struct ath10k *ar)
 {
-	ath10k_pci_kill_tasklet(ar);
+	ath10k_pci_rx_retry_sync(ar);
+	netif_napi_del(&ar->napi);
 	ath10k_pci_ce_deinit(ar);
 	ath10k_pci_free_pipes(ar);
 }
@@ -3298,7 +3317,7 @@ static int ath10k_pci_probe(struct pci_dev *pdev,
 
 err_free_irq:
 	ath10k_pci_free_irq(ar);
-	ath10k_pci_kill_tasklet(ar);
+	ath10k_pci_rx_retry_sync(ar);
 
 err_deinit_irq:
 	ath10k_pci_deinit_irq(ar);
diff --git a/drivers/net/wireless/ath/ath10k/pci.h b/drivers/net/wireless/ath/ath10k/pci.h
index 6eca1df2ce60..9854ad56b2de 100644
--- a/drivers/net/wireless/ath/ath10k/pci.h
+++ b/drivers/net/wireless/ath/ath10k/pci.h
@@ -177,8 +177,6 @@ struct ath10k_pci {
 	/* Operating interrupt mode */
 	enum ath10k_pci_irq_mode oper_irq_mode;
 
-	struct tasklet_struct intr_tq;
-
 	struct ath10k_pci_pipe pipe_info[CE_COUNT_MAX];
 
 	/* Copy Engine used for Diagnostic Accesses */
@@ -294,8 +292,7 @@ void ath10k_pci_free_pipes(struct ath10k *ar);
 void ath10k_pci_free_pipes(struct ath10k *ar);
 void ath10k_pci_rx_replenish_retry(unsigned long ptr);
 void ath10k_pci_ce_deinit(struct ath10k *ar);
-void ath10k_pci_init_irq_tasklets(struct ath10k *ar);
-void ath10k_pci_kill_tasklet(struct ath10k *ar);
+void ath10k_pci_init_napi(struct ath10k *ar);
 int ath10k_pci_init_pipes(struct ath10k *ar);
 int ath10k_pci_init_config(struct ath10k *ar);
 void ath10k_pci_rx_post(struct ath10k *ar);
@@ -303,6 +300,7 @@ void ath10k_pci_flush(struct ath10k *ar);
 void ath10k_pci_enable_legacy_irq(struct ath10k *ar);
 bool ath10k_pci_irq_pending(struct ath10k *ar);
 void ath10k_pci_disable_and_clear_legacy_irq(struct ath10k *ar);
+void ath10k_pci_irq_msi_fw_mask(struct ath10k *ar);
 int ath10k_pci_wait_for_target_init(struct ath10k *ar);
 int ath10k_pci_setup_resource(struct ath10k *ar);
 void ath10k_pci_release_resource(struct ath10k *ar);
-- 
2.9.2