1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 /* Copyright (C) 2015-2019 Netronome Systems, Inc. */
3 
4 #include <linux/seq_file.h>
5 
6 #include "../nfp_net.h"
7 #include "../nfp_net_dp.h"
8 #include "../nfp_net_xsk.h"
9 #include "nfd3.h"
10 
nfp_nfd3_xsk_tx_bufs_free(struct nfp_net_tx_ring * tx_ring)11 static void nfp_nfd3_xsk_tx_bufs_free(struct nfp_net_tx_ring *tx_ring)
12 {
13 	struct nfp_nfd3_tx_buf *txbuf;
14 	unsigned int idx;
15 
16 	while (tx_ring->rd_p != tx_ring->wr_p) {
17 		idx = D_IDX(tx_ring, tx_ring->rd_p);
18 		txbuf = &tx_ring->txbufs[idx];
19 
20 		txbuf->real_len = 0;
21 
22 		tx_ring->qcp_rd_p++;
23 		tx_ring->rd_p++;
24 
25 		if (tx_ring->r_vec->xsk_pool) {
26 			if (txbuf->is_xsk_tx)
27 				nfp_nfd3_xsk_tx_free(txbuf);
28 
29 			xsk_tx_completed(tx_ring->r_vec->xsk_pool, 1);
30 		}
31 	}
32 }
33 
34 /**
35  * nfp_nfd3_tx_ring_reset() - Free any untransmitted buffers and reset pointers
36  * @dp:		NFP Net data path struct
37  * @tx_ring:	TX ring structure
38  *
39  * Assumes that the device is stopped, must be idempotent.
40  */
41 static void
nfp_nfd3_tx_ring_reset(struct nfp_net_dp * dp,struct nfp_net_tx_ring * tx_ring)42 nfp_nfd3_tx_ring_reset(struct nfp_net_dp *dp, struct nfp_net_tx_ring *tx_ring)
43 {
44 	struct netdev_queue *nd_q;
45 	const skb_frag_t *frag;
46 
47 	while (!tx_ring->is_xdp && tx_ring->rd_p != tx_ring->wr_p) {
48 		struct nfp_nfd3_tx_buf *tx_buf;
49 		struct sk_buff *skb;
50 		int idx, nr_frags;
51 
52 		idx = D_IDX(tx_ring, tx_ring->rd_p);
53 		tx_buf = &tx_ring->txbufs[idx];
54 
55 		skb = tx_ring->txbufs[idx].skb;
56 		nr_frags = skb_shinfo(skb)->nr_frags;
57 
58 		if (tx_buf->fidx == -1) {
59 			/* unmap head */
60 			dma_unmap_single(dp->dev, tx_buf->dma_addr,
61 					 skb_headlen(skb), DMA_TO_DEVICE);
62 		} else {
63 			/* unmap fragment */
64 			frag = &skb_shinfo(skb)->frags[tx_buf->fidx];
65 			dma_unmap_page(dp->dev, tx_buf->dma_addr,
66 				       skb_frag_size(frag), DMA_TO_DEVICE);
67 		}
68 
69 		/* check for last gather fragment */
70 		if (tx_buf->fidx == nr_frags - 1)
71 			dev_kfree_skb_any(skb);
72 
73 		tx_buf->dma_addr = 0;
74 		tx_buf->skb = NULL;
75 		tx_buf->fidx = -2;
76 
77 		tx_ring->qcp_rd_p++;
78 		tx_ring->rd_p++;
79 	}
80 
81 	if (tx_ring->is_xdp)
82 		nfp_nfd3_xsk_tx_bufs_free(tx_ring);
83 
84 	memset(tx_ring->txds, 0, tx_ring->size);
85 	tx_ring->wr_p = 0;
86 	tx_ring->rd_p = 0;
87 	tx_ring->qcp_rd_p = 0;
88 	tx_ring->wr_ptr_add = 0;
89 
90 	if (tx_ring->is_xdp || !dp->netdev)
91 		return;
92 
93 	nd_q = netdev_get_tx_queue(dp->netdev, tx_ring->idx);
94 	netdev_tx_reset_queue(nd_q);
95 }
96 
97 /**
98  * nfp_nfd3_tx_ring_free() - Free resources allocated to a TX ring
99  * @tx_ring:   TX ring to free
100  */
nfp_nfd3_tx_ring_free(struct nfp_net_tx_ring * tx_ring)101 static void nfp_nfd3_tx_ring_free(struct nfp_net_tx_ring *tx_ring)
102 {
103 	struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
104 	struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
105 
106 	kvfree(tx_ring->txbufs);
107 
108 	if (tx_ring->txds)
109 		dma_free_coherent(dp->dev, tx_ring->size,
110 				  tx_ring->txds, tx_ring->dma);
111 
112 	tx_ring->cnt = 0;
113 	tx_ring->txbufs = NULL;
114 	tx_ring->txds = NULL;
115 	tx_ring->dma = 0;
116 	tx_ring->size = 0;
117 }
118 
119 /**
120  * nfp_nfd3_tx_ring_alloc() - Allocate resource for a TX ring
121  * @dp:        NFP Net data path struct
122  * @tx_ring:   TX Ring structure to allocate
123  *
124  * Return: 0 on success, negative errno otherwise.
125  */
126 static int
nfp_nfd3_tx_ring_alloc(struct nfp_net_dp * dp,struct nfp_net_tx_ring * tx_ring)127 nfp_nfd3_tx_ring_alloc(struct nfp_net_dp *dp, struct nfp_net_tx_ring *tx_ring)
128 {
129 	struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
130 
131 	tx_ring->cnt = dp->txd_cnt;
132 
133 	tx_ring->size = array_size(tx_ring->cnt, sizeof(*tx_ring->txds));
134 	tx_ring->txds = dma_alloc_coherent(dp->dev, tx_ring->size,
135 					   &tx_ring->dma,
136 					   GFP_KERNEL | __GFP_NOWARN);
137 	if (!tx_ring->txds) {
138 		netdev_warn(dp->netdev, "failed to allocate TX descriptor ring memory, requested descriptor count: %d, consider lowering descriptor count\n",
139 			    tx_ring->cnt);
140 		goto err_alloc;
141 	}
142 
143 	tx_ring->txbufs = kvcalloc(tx_ring->cnt, sizeof(*tx_ring->txbufs),
144 				   GFP_KERNEL);
145 	if (!tx_ring->txbufs)
146 		goto err_alloc;
147 
148 	if (!tx_ring->is_xdp && dp->netdev)
149 		netif_set_xps_queue(dp->netdev, &r_vec->affinity_mask,
150 				    tx_ring->idx);
151 
152 	return 0;
153 
154 err_alloc:
155 	nfp_nfd3_tx_ring_free(tx_ring);
156 	return -ENOMEM;
157 }
158 
159 static void
nfp_nfd3_tx_ring_bufs_free(struct nfp_net_dp * dp,struct nfp_net_tx_ring * tx_ring)160 nfp_nfd3_tx_ring_bufs_free(struct nfp_net_dp *dp,
161 			   struct nfp_net_tx_ring *tx_ring)
162 {
163 	unsigned int i;
164 
165 	if (!tx_ring->is_xdp)
166 		return;
167 
168 	for (i = 0; i < tx_ring->cnt; i++) {
169 		if (!tx_ring->txbufs[i].frag)
170 			return;
171 
172 		nfp_net_dma_unmap_rx(dp, tx_ring->txbufs[i].dma_addr);
173 		__free_page(virt_to_page(tx_ring->txbufs[i].frag));
174 	}
175 }
176 
177 static int
nfp_nfd3_tx_ring_bufs_alloc(struct nfp_net_dp * dp,struct nfp_net_tx_ring * tx_ring)178 nfp_nfd3_tx_ring_bufs_alloc(struct nfp_net_dp *dp,
179 			    struct nfp_net_tx_ring *tx_ring)
180 {
181 	struct nfp_nfd3_tx_buf *txbufs = tx_ring->txbufs;
182 	unsigned int i;
183 
184 	if (!tx_ring->is_xdp)
185 		return 0;
186 
187 	for (i = 0; i < tx_ring->cnt; i++) {
188 		txbufs[i].frag = nfp_net_rx_alloc_one(dp, &txbufs[i].dma_addr);
189 		if (!txbufs[i].frag) {
190 			nfp_nfd3_tx_ring_bufs_free(dp, tx_ring);
191 			return -ENOMEM;
192 		}
193 	}
194 
195 	return 0;
196 }
197 
198 static void
nfp_nfd3_print_tx_descs(struct seq_file * file,struct nfp_net_r_vector * r_vec,struct nfp_net_tx_ring * tx_ring,u32 d_rd_p,u32 d_wr_p)199 nfp_nfd3_print_tx_descs(struct seq_file *file,
200 			struct nfp_net_r_vector *r_vec,
201 			struct nfp_net_tx_ring *tx_ring,
202 			u32 d_rd_p, u32 d_wr_p)
203 {
204 	struct nfp_nfd3_tx_desc *txd;
205 	u32 txd_cnt = tx_ring->cnt;
206 	int i;
207 
208 	for (i = 0; i < txd_cnt; i++) {
209 		struct xdp_buff *xdp;
210 		struct sk_buff *skb;
211 
212 		txd = &tx_ring->txds[i];
213 		seq_printf(file, "%04d: 0x%08x 0x%08x 0x%08x 0x%08x", i,
214 			   txd->vals[0], txd->vals[1],
215 			   txd->vals[2], txd->vals[3]);
216 
217 		if (!tx_ring->is_xdp) {
218 			skb = READ_ONCE(tx_ring->txbufs[i].skb);
219 			if (skb)
220 				seq_printf(file, " skb->head=%p skb->data=%p",
221 					   skb->head, skb->data);
222 		} else {
223 			xdp = READ_ONCE(tx_ring->txbufs[i].xdp);
224 			if (xdp)
225 				seq_printf(file, " xdp->data=%p", xdp->data);
226 		}
227 
228 		if (tx_ring->txbufs[i].dma_addr)
229 			seq_printf(file, " dma_addr=%pad",
230 				   &tx_ring->txbufs[i].dma_addr);
231 
232 		if (i == tx_ring->rd_p % txd_cnt)
233 			seq_puts(file, " H_RD");
234 		if (i == tx_ring->wr_p % txd_cnt)
235 			seq_puts(file, " H_WR");
236 		if (i == d_rd_p % txd_cnt)
237 			seq_puts(file, " D_RD");
238 		if (i == d_wr_p % txd_cnt)
239 			seq_puts(file, " D_WR");
240 
241 		seq_putc(file, '\n');
242 	}
243 }
244 
245 #define NFP_NFD3_CFG_CTRL_SUPPORTED					\
246 	(NFP_NET_CFG_CTRL_ENABLE | NFP_NET_CFG_CTRL_PROMISC |		\
247 	 NFP_NET_CFG_CTRL_L2BC | NFP_NET_CFG_CTRL_L2MC |		\
248 	 NFP_NET_CFG_CTRL_RXCSUM | NFP_NET_CFG_CTRL_TXCSUM |		\
249 	 NFP_NET_CFG_CTRL_RXVLAN | NFP_NET_CFG_CTRL_TXVLAN |		\
250 	 NFP_NET_CFG_CTRL_GATHER | NFP_NET_CFG_CTRL_LSO |		\
251 	 NFP_NET_CFG_CTRL_CTAG_FILTER | NFP_NET_CFG_CTRL_CMSG_DATA |	\
252 	 NFP_NET_CFG_CTRL_RINGCFG | NFP_NET_CFG_CTRL_RSS |		\
253 	 NFP_NET_CFG_CTRL_IRQMOD | NFP_NET_CFG_CTRL_TXRWB |		\
254 	 NFP_NET_CFG_CTRL_VXLAN | NFP_NET_CFG_CTRL_NVGRE |		\
255 	 NFP_NET_CFG_CTRL_BPF | NFP_NET_CFG_CTRL_LSO2 |			\
256 	 NFP_NET_CFG_CTRL_RSS2 | NFP_NET_CFG_CTRL_CSUM_COMPLETE |	\
257 	 NFP_NET_CFG_CTRL_LIVE_ADDR)
258 
259 const struct nfp_dp_ops nfp_nfd3_ops = {
260 	.version		= NFP_NFD_VER_NFD3,
261 	.tx_min_desc_per_pkt	= 1,
262 	.cap_mask		= NFP_NFD3_CFG_CTRL_SUPPORTED,
263 	.poll			= nfp_nfd3_poll,
264 	.xsk_poll		= nfp_nfd3_xsk_poll,
265 	.ctrl_poll		= nfp_nfd3_ctrl_poll,
266 	.xmit			= nfp_nfd3_tx,
267 	.ctrl_tx_one		= nfp_nfd3_ctrl_tx_one,
268 	.rx_ring_fill_freelist	= nfp_nfd3_rx_ring_fill_freelist,
269 	.tx_ring_alloc		= nfp_nfd3_tx_ring_alloc,
270 	.tx_ring_reset		= nfp_nfd3_tx_ring_reset,
271 	.tx_ring_free		= nfp_nfd3_tx_ring_free,
272 	.tx_ring_bufs_alloc	= nfp_nfd3_tx_ring_bufs_alloc,
273 	.tx_ring_bufs_free	= nfp_nfd3_tx_ring_bufs_free,
274 	.print_tx_descs		= nfp_nfd3_print_tx_descs
275 };
276