1 files changed, 442 insertions, 0 deletions

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_dp.c b/drivers/net/ethernet/netronome/nfp/nfp_net_dp.c
new file mode 100644
index 000000000000..34dd94811df3
--- /dev/null
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_dp.c
@@ -0,0 +1,442 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/* Copyright (C) 2015-2019 Netronome Systems, Inc. */
+
+#include "nfp_app.h"
+#include "nfp_net_dp.h"
+#include "nfp_net_xsk.h"
+
+/**
+ * nfp_net_rx_alloc_one() - Allocate and map page frag for RX
+ * @dp:		NFP Net data path struct
+ * @dma_addr:	Pointer to storage for DMA address (output param)
+ *
+ * This function will allcate a new page frag, map it for DMA.
+ *
+ * Return: allocated page frag or NULL on failure.
+ */
+void *nfp_net_rx_alloc_one(struct nfp_net_dp *dp, dma_addr_t *dma_addr)
+{
+	void *frag;
+
+	if (!dp->xdp_prog) {
+		frag = netdev_alloc_frag(dp->fl_bufsz);
+	} else {
+		struct page *page;
+
+		page = alloc_page(GFP_KERNEL);
+		frag = page ? page_address(page) : NULL;
+	}
+	if (!frag) {
+		nn_dp_warn(dp, "Failed to alloc receive page frag\n");
+		return NULL;
+	}
+
+	*dma_addr = nfp_net_dma_map_rx(dp, frag);
+	if (dma_mapping_error(dp->dev, *dma_addr)) {
+		nfp_net_free_frag(frag, dp->xdp_prog);
+		nn_dp_warn(dp, "Failed to map DMA RX buffer\n");
+		return NULL;
+	}
+
+	return frag;
+}
+
+/**
+ * nfp_net_tx_ring_init() - Fill in the boilerplate for a TX ring
+ * @tx_ring:  TX ring structure
+ * @dp:	      NFP Net data path struct
+ * @r_vec:    IRQ vector servicing this ring
+ * @idx:      Ring index
+ * @is_xdp:   Is this an XDP TX ring?
+ */
+static void
+nfp_net_tx_ring_init(struct nfp_net_tx_ring *tx_ring, struct nfp_net_dp *dp,
+		     struct nfp_net_r_vector *r_vec, unsigned int idx,
+		     bool is_xdp)
+{
+	struct nfp_net *nn = r_vec->nfp_net;
+
+	tx_ring->idx = idx;
+	tx_ring->r_vec = r_vec;
+	tx_ring->is_xdp = is_xdp;
+	u64_stats_init(&tx_ring->r_vec->tx_sync);
+
+	tx_ring->qcidx = tx_ring->idx * nn->stride_tx;
+	tx_ring->txrwb = dp->txrwb ? &dp->txrwb[idx] : NULL;
+	tx_ring->qcp_q = nn->tx_bar + NFP_QCP_QUEUE_OFF(tx_ring->qcidx);
+}
+
+/**
+ * nfp_net_rx_ring_init() - Fill in the boilerplate for a RX ring
+ * @rx_ring:  RX ring structure
+ * @r_vec:    IRQ vector servicing this ring
+ * @idx:      Ring index
+ */
+static void
+nfp_net_rx_ring_init(struct nfp_net_rx_ring *rx_ring,
+		     struct nfp_net_r_vector *r_vec, unsigned int idx)
+{
+	struct nfp_net *nn = r_vec->nfp_net;
+
+	rx_ring->idx = idx;
+	rx_ring->r_vec = r_vec;
+	u64_stats_init(&rx_ring->r_vec->rx_sync);
+
+	rx_ring->fl_qcidx = rx_ring->idx * nn->stride_rx;
+	rx_ring->qcp_fl = nn->rx_bar + NFP_QCP_QUEUE_OFF(rx_ring->fl_qcidx);
+}
+
+/**
+ * nfp_net_rx_ring_reset() - Reflect in SW state of freelist after disable
+ * @rx_ring:	RX ring structure
+ *
+ * Assumes that the device is stopped, must be idempotent.
+ */
+void nfp_net_rx_ring_reset(struct nfp_net_rx_ring *rx_ring)
+{
+	unsigned int wr_idx, last_idx;
+
+	/* wr_p == rd_p means ring was never fed FL bufs.  RX rings are always
+	 * kept at cnt - 1 FL bufs.
+	 */
+	if (rx_ring->wr_p == 0 && rx_ring->rd_p == 0)
+		return;
+
+	/* Move the empty entry to the end of the list */
+	wr_idx = D_IDX(rx_ring, rx_ring->wr_p);
+	last_idx = rx_ring->cnt - 1;
+	if (rx_ring->r_vec->xsk_pool) {
+		rx_ring->xsk_rxbufs[wr_idx] = rx_ring->xsk_rxbufs[last_idx];
+		memset(&rx_ring->xsk_rxbufs[last_idx], 0,
+		       sizeof(*rx_ring->xsk_rxbufs));
+	} else {
+		rx_ring->rxbufs[wr_idx] = rx_ring->rxbufs[last_idx];
+		memset(&rx_ring->rxbufs[last_idx], 0, sizeof(*rx_ring->rxbufs));
+	}
+
+	memset(rx_ring->rxds, 0, rx_ring->size);
+	rx_ring->wr_p = 0;
+	rx_ring->rd_p = 0;
+}
+
+/**
+ * nfp_net_rx_ring_bufs_free() - Free any buffers currently on the RX ring
+ * @dp:		NFP Net data path struct
+ * @rx_ring:	RX ring to remove buffers from
+ *
+ * Assumes that the device is stopped and buffers are in [0, ring->cnt - 1)
+ * entries.  After device is disabled nfp_net_rx_ring_reset() must be called
+ * to restore required ring geometry.
+ */
+static void
+nfp_net_rx_ring_bufs_free(struct nfp_net_dp *dp,
+			  struct nfp_net_rx_ring *rx_ring)
+{
+	unsigned int i;
+
+	if (nfp_net_has_xsk_pool_slow(dp, rx_ring->idx))
+		return;
+
+	for (i = 0; i < rx_ring->cnt - 1; i++) {
+		/* NULL skb can only happen when initial filling of the ring
+		 * fails to allocate enough buffers and calls here to free
+		 * already allocated ones.
+		 */
+		if (!rx_ring->rxbufs[i].frag)
+			continue;
+
+		nfp_net_dma_unmap_rx(dp, rx_ring->rxbufs[i].dma_addr);
+		nfp_net_free_frag(rx_ring->rxbufs[i].frag, dp->xdp_prog);
+		rx_ring->rxbufs[i].dma_addr = 0;
+		rx_ring->rxbufs[i].frag = NULL;
+	}
+}
+
+/**
+ * nfp_net_rx_ring_bufs_alloc() - Fill RX ring with buffers (don't give to FW)
+ * @dp:		NFP Net data path struct
+ * @rx_ring:	RX ring to remove buffers from
+ */
+static int
+nfp_net_rx_ring_bufs_alloc(struct nfp_net_dp *dp,
+			   struct nfp_net_rx_ring *rx_ring)
+{
+	struct nfp_net_rx_buf *rxbufs;
+	unsigned int i;
+
+	if (nfp_net_has_xsk_pool_slow(dp, rx_ring->idx))
+		return 0;
+
+	rxbufs = rx_ring->rxbufs;
+
+	for (i = 0; i < rx_ring->cnt - 1; i++) {
+		rxbufs[i].frag = nfp_net_rx_alloc_one(dp, &rxbufs[i].dma_addr);
+		if (!rxbufs[i].frag) {
+			nfp_net_rx_ring_bufs_free(dp, rx_ring);
+			return -ENOMEM;
+		}
+	}
+
+	return 0;
+}
+
+int nfp_net_tx_rings_prepare(struct nfp_net *nn, struct nfp_net_dp *dp)
+{
+	unsigned int r;
+
+	dp->tx_rings = kcalloc(dp->num_tx_rings, sizeof(*dp->tx_rings),
+			       GFP_KERNEL);
+	if (!dp->tx_rings)
+		return -ENOMEM;
+
+	if (dp->ctrl & NFP_NET_CFG_CTRL_TXRWB) {
+		dp->txrwb = dma_alloc_coherent(dp->dev,
+					       dp->num_tx_rings * sizeof(u64),
+					       &dp->txrwb_dma, GFP_KERNEL);
+		if (!dp->txrwb)
+			goto err_free_rings;
+	}
+
+	for (r = 0; r < dp->num_tx_rings; r++) {
+		int bias = 0;
+
+		if (r >= dp->num_stack_tx_rings)
+			bias = dp->num_stack_tx_rings;
+
+		nfp_net_tx_ring_init(&dp->tx_rings[r], dp,
+				     &nn->r_vecs[r - bias], r, bias);
+
+		if (nfp_net_tx_ring_alloc(dp, &dp->tx_rings[r]))
+			goto err_free_prev;
+
+		if (nfp_net_tx_ring_bufs_alloc(dp, &dp->tx_rings[r]))
+			goto err_free_ring;
+	}
+
+	return 0;
+
+err_free_prev:
+	while (r--) {
+		nfp_net_tx_ring_bufs_free(dp, &dp->tx_rings[r]);
+err_free_ring:
+		nfp_net_tx_ring_free(dp, &dp->tx_rings[r]);
+	}
+	if (dp->txrwb)
+		dma_free_coherent(dp->dev, dp->num_tx_rings * sizeof(u64),
+				  dp->txrwb, dp->txrwb_dma);
+err_free_rings:
+	kfree(dp->tx_rings);
+	return -ENOMEM;
+}
+
+void nfp_net_tx_rings_free(struct nfp_net_dp *dp)
+{
+	unsigned int r;
+
+	for (r = 0; r < dp->num_tx_rings; r++) {
+		nfp_net_tx_ring_bufs_free(dp, &dp->tx_rings[r]);
+		nfp_net_tx_ring_free(dp, &dp->tx_rings[r]);
+	}
+
+	if (dp->txrwb)
+		dma_free_coherent(dp->dev, dp->num_tx_rings * sizeof(u64),
+				  dp->txrwb, dp->txrwb_dma);
+	kfree(dp->tx_rings);
+}
+
+/**
+ * nfp_net_rx_ring_free() - Free resources allocated to a RX ring
+ * @rx_ring:  RX ring to free
+ */
+static void nfp_net_rx_ring_free(struct nfp_net_rx_ring *rx_ring)
+{
+	struct nfp_net_r_vector *r_vec = rx_ring->r_vec;
+	struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
+
+	if (dp->netdev)
+		xdp_rxq_info_unreg(&rx_ring->xdp_rxq);
+
+	if (nfp_net_has_xsk_pool_slow(dp, rx_ring->idx))
+		kvfree(rx_ring->xsk_rxbufs);
+	else
+		kvfree(rx_ring->rxbufs);
+
+	if (rx_ring->rxds)
+		dma_free_coherent(dp->dev, rx_ring->size,
+				  rx_ring->rxds, rx_ring->dma);
+
+	rx_ring->cnt = 0;
+	rx_ring->rxbufs = NULL;
+	rx_ring->xsk_rxbufs = NULL;
+	rx_ring->rxds = NULL;
+	rx_ring->dma = 0;
+	rx_ring->size = 0;
+}
+
+/**
+ * nfp_net_rx_ring_alloc() - Allocate resource for a RX ring
+ * @dp:	      NFP Net data path struct
+ * @rx_ring:  RX ring to allocate
+ *
+ * Return: 0 on success, negative errno otherwise.
+ */
+static int
+nfp_net_rx_ring_alloc(struct nfp_net_dp *dp, struct nfp_net_rx_ring *rx_ring)
+{
+	enum xdp_mem_type mem_type;
+	size_t rxbuf_sw_desc_sz;
+	int err;
+
+	if (nfp_net_has_xsk_pool_slow(dp, rx_ring->idx)) {
+		mem_type = MEM_TYPE_XSK_BUFF_POOL;
+		rxbuf_sw_desc_sz = sizeof(*rx_ring->xsk_rxbufs);
+	} else {
+		mem_type = MEM_TYPE_PAGE_ORDER0;
+		rxbuf_sw_desc_sz = sizeof(*rx_ring->rxbufs);
+	}
+
+	if (dp->netdev) {
+		err = xdp_rxq_info_reg(&rx_ring->xdp_rxq, dp->netdev,
+				       rx_ring->idx, rx_ring->r_vec->napi.napi_id);
+		if (err < 0)
+			return err;
+
+		err = xdp_rxq_info_reg_mem_model(&rx_ring->xdp_rxq, mem_type, NULL);
+		if (err)
+			goto err_alloc;
+	}
+
+	rx_ring->cnt = dp->rxd_cnt;
+	rx_ring->size = array_size(rx_ring->cnt, sizeof(*rx_ring->rxds));
+	rx_ring->rxds = dma_alloc_coherent(dp->dev, rx_ring->size,
+					   &rx_ring->dma,
+					   GFP_KERNEL | __GFP_NOWARN);
+	if (!rx_ring->rxds) {
+		netdev_warn(dp->netdev, "failed to allocate RX descriptor ring memory, requested descriptor count: %d, consider lowering descriptor count\n",
+			    rx_ring->cnt);
+		goto err_alloc;
+	}
+
+	if (nfp_net_has_xsk_pool_slow(dp, rx_ring->idx)) {
+		rx_ring->xsk_rxbufs = kvcalloc(rx_ring->cnt, rxbuf_sw_desc_sz,
+					       GFP_KERNEL);
+		if (!rx_ring->xsk_rxbufs)
+			goto err_alloc;
+	} else {
+		rx_ring->rxbufs = kvcalloc(rx_ring->cnt, rxbuf_sw_desc_sz,
+					   GFP_KERNEL);
+		if (!rx_ring->rxbufs)
+			goto err_alloc;
+	}
+
+	return 0;
+
+err_alloc:
+	nfp_net_rx_ring_free(rx_ring);
+	return -ENOMEM;
+}
+
+int nfp_net_rx_rings_prepare(struct nfp_net *nn, struct nfp_net_dp *dp)
+{
+	unsigned int r;
+
+	dp->rx_rings = kcalloc(dp->num_rx_rings, sizeof(*dp->rx_rings),
+			       GFP_KERNEL);
+	if (!dp->rx_rings)
+		return -ENOMEM;
+
+	for (r = 0; r < dp->num_rx_rings; r++) {
+		nfp_net_rx_ring_init(&dp->rx_rings[r], &nn->r_vecs[r], r);
+
+		if (nfp_net_rx_ring_alloc(dp, &dp->rx_rings[r]))
+			goto err_free_prev;
+
+		if (nfp_net_rx_ring_bufs_alloc(dp, &dp->rx_rings[r]))
+			goto err_free_ring;
+	}
+
+	return 0;
+
+err_free_prev:
+	while (r--) {
+		nfp_net_rx_ring_bufs_free(dp, &dp->rx_rings[r]);
+err_free_ring:
+		nfp_net_rx_ring_free(&dp->rx_rings[r]);
+	}
+	kfree(dp->rx_rings);
+	return -ENOMEM;
+}
+
+void nfp_net_rx_rings_free(struct nfp_net_dp *dp)
+{
+	unsigned int r;
+
+	for (r = 0; r < dp->num_rx_rings; r++) {
+		nfp_net_rx_ring_bufs_free(dp, &dp->rx_rings[r]);
+		nfp_net_rx_ring_free(&dp->rx_rings[r]);
+	}
+
+	kfree(dp->rx_rings);
+}
+
+void
+nfp_net_rx_ring_hw_cfg_write(struct nfp_net *nn,
+			     struct nfp_net_rx_ring *rx_ring, unsigned int idx)
+{
+	/* Write the DMA address, size and MSI-X info to the device */
+	nn_writeq(nn, NFP_NET_CFG_RXR_ADDR(idx), rx_ring->dma);
+	nn_writeb(nn, NFP_NET_CFG_RXR_SZ(idx), ilog2(rx_ring->cnt));
+	nn_writeb(nn, NFP_NET_CFG_RXR_VEC(idx), rx_ring->r_vec->irq_entry);
+}
+
+void
+nfp_net_tx_ring_hw_cfg_write(struct nfp_net *nn,
+			     struct nfp_net_tx_ring *tx_ring, unsigned int idx)
+{
+	nn_writeq(nn, NFP_NET_CFG_TXR_ADDR(idx), tx_ring->dma);
+	if (tx_ring->txrwb) {
+		*tx_ring->txrwb = 0;
+		nn_writeq(nn, NFP_NET_CFG_TXR_WB_ADDR(idx),
+			  nn->dp.txrwb_dma + idx * sizeof(u64));
+	}
+	nn_writeb(nn, NFP_NET_CFG_TXR_SZ(idx), ilog2(tx_ring->cnt));
+	nn_writeb(nn, NFP_NET_CFG_TXR_VEC(idx), tx_ring->r_vec->irq_entry);
+}
+
+void nfp_net_vec_clear_ring_data(struct nfp_net *nn, unsigned int idx)
+{
+	nn_writeq(nn, NFP_NET_CFG_RXR_ADDR(idx), 0);
+	nn_writeb(nn, NFP_NET_CFG_RXR_SZ(idx), 0);
+	nn_writeb(nn, NFP_NET_CFG_RXR_VEC(idx), 0);
+
+	nn_writeq(nn, NFP_NET_CFG_TXR_ADDR(idx), 0);
+	nn_writeq(nn, NFP_NET_CFG_TXR_WB_ADDR(idx), 0);
+	nn_writeb(nn, NFP_NET_CFG_TXR_SZ(idx), 0);
+	nn_writeb(nn, NFP_NET_CFG_TXR_VEC(idx), 0);
+}
+
+netdev_tx_t nfp_net_tx(struct sk_buff *skb, struct net_device *netdev)
+{
+	struct nfp_net *nn = netdev_priv(netdev);
+
+	return nn->dp.ops->xmit(skb, netdev);
+}
+
+bool __nfp_ctrl_tx(struct nfp_net *nn, struct sk_buff *skb)
+{
+	struct nfp_net_r_vector *r_vec = &nn->r_vecs[0];
+
+	return nn->dp.ops->ctrl_tx_one(nn, r_vec, skb, false);
+}
+
+bool nfp_ctrl_tx(struct nfp_net *nn, struct sk_buff *skb)
+{
+	struct nfp_net_r_vector *r_vec = &nn->r_vecs[0];
+	bool ret;
+
+	spin_lock_bh(&r_vec->lock);
+	ret = nn->dp.ops->ctrl_tx_one(nn, r_vec, skb, false);
+	spin_unlock_bh(&r_vec->lock);
+
+	return ret;
+}