--- /dev/null
+From 3affa310de523d63e52ea8e2efb3c476df29e414 Mon Sep 17 00:00:00 2001
+From: Lorenzo Bianconi <lorenzo@kernel.org>
+Date: Tue, 29 Oct 2024 13:17:09 +0100
+Subject: [PATCH 1/2] net: airoha: Read completion queue data in
+ airoha_qdma_tx_napi_poll()
+
+In order to avoid any possible race, read completion queue head and
+pending entry in airoha_qdma_tx_napi_poll routine instead of doing it in
+airoha_irq_handler. Remove unused airoha_tx_irq_queue unused fields.
+This is a preliminary patch to add Qdisc offload for airoha_eth driver.
+
+Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
+Link: https://patch.msgid.link/20241029-airoha-en7581-tx-napi-work-v1-1-96ad1686b946@kernel.org
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+---
+ drivers/net/ethernet/mediatek/airoha_eth.c | 31 +++++++++-------------
+ 1 file changed, 13 insertions(+), 18 deletions(-)
+
+--- a/drivers/net/ethernet/mediatek/airoha_eth.c
++++ b/drivers/net/ethernet/mediatek/airoha_eth.c
+@@ -752,11 +752,9 @@ struct airoha_tx_irq_queue {
+ struct airoha_qdma *qdma;
+
+ struct napi_struct napi;
+- u32 *q;
+
+ int size;
+- int queued;
+- u16 head;
++ u32 *q;
+ };
+
+ struct airoha_hw_stats {
+@@ -1656,25 +1654,31 @@ static int airoha_qdma_init_rx(struct ai
+ static int airoha_qdma_tx_napi_poll(struct napi_struct *napi, int budget)
+ {
+ struct airoha_tx_irq_queue *irq_q;
++ int id, done = 0, irq_queued;
+ struct airoha_qdma *qdma;
+ struct airoha_eth *eth;
+- int id, done = 0;
++ u32 status, head;
+
+ irq_q = container_of(napi, struct airoha_tx_irq_queue, napi);
+ qdma = irq_q->qdma;
+ id = irq_q - &qdma->q_tx_irq[0];
+ eth = qdma->eth;
+
+- while (irq_q->queued > 0 && done < budget) {
+- u32 qid, last, val = irq_q->q[irq_q->head];
++ status = airoha_qdma_rr(qdma, REG_IRQ_STATUS(id));
++ head = FIELD_GET(IRQ_HEAD_IDX_MASK, status);
++ head = head % irq_q->size;
++ irq_queued = FIELD_GET(IRQ_ENTRY_LEN_MASK, status);
++
++ while (irq_queued > 0 && done < budget) {
++ u32 qid, last, val = irq_q->q[head];
+ struct airoha_queue *q;
+
+ if (val == 0xff)
+ break;
+
+- irq_q->q[irq_q->head] = 0xff; /* mark as done */
+- irq_q->head = (irq_q->head + 1) % irq_q->size;
+- irq_q->queued--;
++ irq_q->q[head] = 0xff; /* mark as done */
++ head = (head + 1) % irq_q->size;
++ irq_queued--;
+ done++;
+
+ last = FIELD_GET(IRQ_DESC_IDX_MASK, val);
+@@ -2026,20 +2030,11 @@ static irqreturn_t airoha_irq_handler(in
+
+ if (intr[0] & INT_TX_MASK) {
+ for (i = 0; i < ARRAY_SIZE(qdma->q_tx_irq); i++) {
+- struct airoha_tx_irq_queue *irq_q = &qdma->q_tx_irq[i];
+- u32 status, head;
+-
+ if (!(intr[0] & TX_DONE_INT_MASK(i)))
+ continue;
+
+ airoha_qdma_irq_disable(qdma, QDMA_INT_REG_IDX0,
+ TX_DONE_INT_MASK(i));
+-
+- status = airoha_qdma_rr(qdma, REG_IRQ_STATUS(i));
+- head = FIELD_GET(IRQ_HEAD_IDX_MASK, status);
+- irq_q->head = head % irq_q->size;
+- irq_q->queued = FIELD_GET(IRQ_ENTRY_LEN_MASK, status);
+-
+ napi_schedule(&qdma->q_tx_irq[i].napi);
+ }
+ }
--- /dev/null
+From 0c729f53b8c33b9e5eadc2d5e673759e3510501e Mon Sep 17 00:00:00 2001
+From: Lorenzo Bianconi <lorenzo@kernel.org>
+Date: Tue, 29 Oct 2024 13:17:10 +0100
+Subject: [PATCH 2/2] net: airoha: Simplify Tx napi logic
+
+Simplify Tx napi logic relying just on the packet index provided by
+completion queue indicating the completed packet that can be removed
+from the Tx DMA ring.
+This is a preliminary patch to add Qdisc offload for airoha_eth driver.
+
+Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
+Link: https://patch.msgid.link/20241029-airoha-en7581-tx-napi-work-v1-2-96ad1686b946@kernel.org
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+---
+ drivers/net/ethernet/mediatek/airoha_eth.c | 73 ++++++++++++----------
+ 1 file changed, 41 insertions(+), 32 deletions(-)
+
+--- a/drivers/net/ethernet/mediatek/airoha_eth.c
++++ b/drivers/net/ethernet/mediatek/airoha_eth.c
+@@ -1670,8 +1670,12 @@ static int airoha_qdma_tx_napi_poll(stru
+ irq_queued = FIELD_GET(IRQ_ENTRY_LEN_MASK, status);
+
+ while (irq_queued > 0 && done < budget) {
+- u32 qid, last, val = irq_q->q[head];
++ u32 qid, val = irq_q->q[head];
++ struct airoha_qdma_desc *desc;
++ struct airoha_queue_entry *e;
+ struct airoha_queue *q;
++ u32 index, desc_ctrl;
++ struct sk_buff *skb;
+
+ if (val == 0xff)
+ break;
+@@ -1681,9 +1685,7 @@ static int airoha_qdma_tx_napi_poll(stru
+ irq_queued--;
+ done++;
+
+- last = FIELD_GET(IRQ_DESC_IDX_MASK, val);
+ qid = FIELD_GET(IRQ_RING_IDX_MASK, val);
+-
+ if (qid >= ARRAY_SIZE(qdma->q_tx))
+ continue;
+
+@@ -1691,46 +1693,53 @@ static int airoha_qdma_tx_napi_poll(stru
+ if (!q->ndesc)
+ continue;
+
++ index = FIELD_GET(IRQ_DESC_IDX_MASK, val);
++ if (index >= q->ndesc)
++ continue;
++
+ spin_lock_bh(&q->lock);
+
+- while (q->queued > 0) {
+- struct airoha_qdma_desc *desc = &q->desc[q->tail];
+- struct airoha_queue_entry *e = &q->entry[q->tail];
+- u32 desc_ctrl = le32_to_cpu(desc->ctrl);
+- struct sk_buff *skb = e->skb;
+- u16 index = q->tail;
+-
+- if (!(desc_ctrl & QDMA_DESC_DONE_MASK) &&
+- !(desc_ctrl & QDMA_DESC_DROP_MASK))
+- break;
++ if (!q->queued)
++ goto unlock;
+
+- q->tail = (q->tail + 1) % q->ndesc;
+- q->queued--;
++ desc = &q->desc[index];
++ desc_ctrl = le32_to_cpu(desc->ctrl);
+
+- dma_unmap_single(eth->dev, e->dma_addr, e->dma_len,
+- DMA_TO_DEVICE);
+-
+- WRITE_ONCE(desc->msg0, 0);
+- WRITE_ONCE(desc->msg1, 0);
++ if (!(desc_ctrl & QDMA_DESC_DONE_MASK) &&
++ !(desc_ctrl & QDMA_DESC_DROP_MASK))
++ goto unlock;
++
++ e = &q->entry[index];
++ skb = e->skb;
++
++ dma_unmap_single(eth->dev, e->dma_addr, e->dma_len,
++ DMA_TO_DEVICE);
++ memset(e, 0, sizeof(*e));
++ WRITE_ONCE(desc->msg0, 0);
++ WRITE_ONCE(desc->msg1, 0);
++ q->queued--;
++
++ /* completion ring can report out-of-order indexes if hw QoS
++ * is enabled and packets with different priority are queued
++ * to same DMA ring. Take into account possible out-of-order
++ * reports incrementing DMA ring tail pointer
++ */
++ while (q->tail != q->head && !q->entry[q->tail].dma_addr)
++ q->tail = (q->tail + 1) % q->ndesc;
+
+- if (skb) {
+- u16 queue = skb_get_queue_mapping(skb);
+- struct netdev_queue *txq;
+-
+- txq = netdev_get_tx_queue(skb->dev, queue);
+- netdev_tx_completed_queue(txq, 1, skb->len);
+- if (netif_tx_queue_stopped(txq) &&
+- q->ndesc - q->queued >= q->free_thr)
+- netif_tx_wake_queue(txq);
+-
+- dev_kfree_skb_any(skb);
+- e->skb = NULL;
+- }
++ if (skb) {
++ u16 queue = skb_get_queue_mapping(skb);
++ struct netdev_queue *txq;
++
++ txq = netdev_get_tx_queue(skb->dev, queue);
++ netdev_tx_completed_queue(txq, 1, skb->len);
++ if (netif_tx_queue_stopped(txq) &&
++ q->ndesc - q->queued >= q->free_thr)
++ netif_tx_wake_queue(txq);
+
+- if (index == last)
+- break;
++ dev_kfree_skb_any(skb);
+ }
+-
++unlock:
+ spin_unlock_bh(&q->lock);
+ }
+