1 files changed, 117 insertions, 0 deletions
diff --git a/drivers/net/ethernet/cisco/enic/enic_wq.c b/drivers/net/ethernet/cisco/enic/enic_wq.c
new file mode 100644
index 000000000000..07936f8b4231
--- /dev/null
+++ b/drivers/net/ethernet/cisco/enic/enic_wq.c
@@ -0,0 +1,117 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright 2025 Cisco Systems, Inc.  All rights reserved.
+
+#include <net/netdev_queues.h>
+#include "enic_res.h"
+#include "enic.h"
+#include "enic_wq.h"
+
+#define ENET_CQ_DESC_COMP_NDX_BITS 14
+#define ENET_CQ_DESC_COMP_NDX_MASK GENMASK(ENET_CQ_DESC_COMP_NDX_BITS - 1, 0)
+
+static void enic_wq_cq_desc_dec(const struct cq_desc *desc_arg, bool ext_wq,
+				u8 *type, u8 *color, u16 *q_number,
+				u16 *completed_index)
+{
+	const struct cq_desc *desc = desc_arg;
+	const u8 type_color = desc->type_color;
+
+	*color = (type_color >> CQ_DESC_COLOR_SHIFT) & CQ_DESC_COLOR_MASK;
+
+	/*
+	 * Make sure color bit is read from desc *before* other fields
+	 * are read from desc.  Hardware guarantees color bit is last
+	 * bit (byte) written.  Adding the rmb() prevents the compiler
+	 * and/or CPU from reordering the reads which would potentially
+	 * result in reading stale values.
+	 */
+	rmb();
+
+	*type = type_color & CQ_DESC_TYPE_MASK;
+	*q_number = le16_to_cpu(desc->q_number) & CQ_DESC_Q_NUM_MASK;
+
+	if (ext_wq)
+		*completed_index = le16_to_cpu(desc->completed_index) &
+			ENET_CQ_DESC_COMP_NDX_MASK;
+	else
+		*completed_index = le16_to_cpu(desc->completed_index) &
+			CQ_DESC_COMP_NDX_MASK;
+}
+
+void enic_free_wq_buf(struct vnic_wq *wq, struct vnic_wq_buf *buf)
+{
+	struct enic *enic = vnic_dev_priv(wq->vdev);
+
+	if (buf->sop)
+		dma_unmap_single(&enic->pdev->dev, buf->dma_addr, buf->len,
+				 DMA_TO_DEVICE);
+	else
+		dma_unmap_page(&enic->pdev->dev, buf->dma_addr, buf->len,
+			       DMA_TO_DEVICE);
+
+	if (buf->os_buf)
+		dev_kfree_skb_any(buf->os_buf);
+}
+
+static void enic_wq_free_buf(struct vnic_wq *wq, struct cq_desc *cq_desc,
+			     struct vnic_wq_buf *buf, void *opaque)
+{
+	struct enic *enic = vnic_dev_priv(wq->vdev);
+
+	enic->wq[wq->index].stats.cq_work++;
+	enic->wq[wq->index].stats.cq_bytes += buf->len;
+	enic_free_wq_buf(wq, buf);
+}
+
+static void enic_wq_service(struct vnic_dev *vdev, struct cq_desc *cq_desc,
+			    u8 type, u16 q_number, u16 completed_index)
+{
+	struct enic *enic = vnic_dev_priv(vdev);
+
+	spin_lock(&enic->wq[q_number].lock);
+
+	vnic_wq_service(&enic->wq[q_number].vwq, cq_desc,
+			completed_index, enic_wq_free_buf, NULL);
+
+	if (netif_tx_queue_stopped(netdev_get_tx_queue(enic->netdev, q_number))
+	    && vnic_wq_desc_avail(&enic->wq[q_number].vwq) >=
+	    (MAX_SKB_FRAGS + ENIC_DESC_MAX_SPLITS)) {
+		netif_wake_subqueue(enic->netdev, q_number);
+		enic->wq[q_number].stats.wake++;
+	}
+
+	spin_unlock(&enic->wq[q_number].lock);
+}
+
+unsigned int enic_wq_cq_service(struct enic *enic, unsigned int cq_index,
+				unsigned int work_to_do)
+{
+	struct vnic_cq *cq = &enic->cq[cq_index];
+	u16 q_number, completed_index;
+	unsigned int work_done = 0;
+	struct cq_desc *cq_desc;
+	u8 type, color;
+	bool ext_wq;
+
+	ext_wq = cq->ring.size > ENIC_MAX_WQ_DESCS_DEFAULT;
+
+	cq_desc = (struct cq_desc *)vnic_cq_to_clean(cq);
+	enic_wq_cq_desc_dec(cq_desc, ext_wq, &type, &color,
+			    &q_number, &completed_index);
+
+	while (color != cq->last_color) {
+		enic_wq_service(cq->vdev, cq_desc, type, q_number,
+				completed_index);
+
+		vnic_cq_inc_to_clean(cq);
+
+		if (++work_done >= work_to_do)
+			break;
+
+		cq_desc = (struct cq_desc *)vnic_cq_to_clean(cq);
+		enic_wq_cq_desc_dec(cq_desc, ext_wq, &type, &color,
+				    &q_number, &completed_index);
+	}
+
+	return work_done;
+}