xref: /linux/drivers/net/ethernet/chelsio/cxgb4/smt.c (revision 96ac6d435100450f0565708d9b885ea2a7400e0a)
1 /*
2  * This file is part of the Chelsio T4/T5/T6 Ethernet driver for Linux.
3  *
4  * Copyright (c) 2017 Chelsio Communications, Inc. All rights reserved.
5  *
6  * This software is available to you under a choice of one of two
7  * licenses.  You may choose to be licensed under the terms of the GNU
8  * General Public License (GPL) Version 2, available from the file
9  * COPYING in the main directory of this source tree, or the
10  * OpenIB.org BSD license below:
11  *
12  *     Redistribution and use in source and binary forms, with or
13  *     without modification, are permitted provided that the following
14  *     conditions are met:
15  *
16  *      - Redistributions of source code must retain the above
17  *        copyright notice, this list of conditions and the following
18  *        disclaimer.
19  *
20  *      - Redistributions in binary form must reproduce the above
21  *        copyright notice, this list of conditions and the following
22  *        disclaimer in the documentation and/or other materials
23  *        provided with the distribution.
24  *
25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32  * SOFTWARE.
33  */
34 
35 #include "cxgb4.h"
36 #include "smt.h"
37 #include "t4_msg.h"
38 #include "t4fw_api.h"
39 #include "t4_regs.h"
40 #include "t4_values.h"
41 
42 struct smt_data *t4_init_smt(void)
43 {
44 	unsigned int smt_size;
45 	struct smt_data *s;
46 	int i;
47 
48 	smt_size = SMT_SIZE;
49 
50 	s = kvzalloc(struct_size(s, smtab, smt_size), GFP_KERNEL);
51 	if (!s)
52 		return NULL;
53 	s->smt_size = smt_size;
54 	rwlock_init(&s->lock);
55 	for (i = 0; i < s->smt_size; ++i) {
56 		s->smtab[i].idx = i;
57 		s->smtab[i].state = SMT_STATE_UNUSED;
58 		memset(&s->smtab[i].src_mac, 0, ETH_ALEN);
59 		spin_lock_init(&s->smtab[i].lock);
60 		atomic_set(&s->smtab[i].refcnt, 0);
61 	}
62 	return s;
63 }
64 
65 static struct smt_entry *find_or_alloc_smte(struct smt_data *s, u8 *smac)
66 {
67 	struct smt_entry *first_free = NULL;
68 	struct smt_entry *e, *end;
69 
70 	for (e = &s->smtab[0], end = &s->smtab[s->smt_size]; e != end; ++e) {
71 		if (atomic_read(&e->refcnt) == 0) {
72 			if (!first_free)
73 				first_free = e;
74 		} else {
75 			if (e->state == SMT_STATE_SWITCHING) {
76 				/* This entry is actually in use. See if we can
77 				 * re-use it ?
78 				 */
79 				if (memcmp(e->src_mac, smac, ETH_ALEN) == 0)
80 					goto found_reuse;
81 			}
82 		}
83 	}
84 
85 	if (first_free) {
86 		e = first_free;
87 		goto found;
88 	}
89 	return NULL;
90 
91 found:
92 	e->state = SMT_STATE_UNUSED;
93 
94 found_reuse:
95 	return e;
96 }
97 
98 static void t4_smte_free(struct smt_entry *e)
99 {
100 	spin_lock_bh(&e->lock);
101 	if (atomic_read(&e->refcnt) == 0) {  /* hasn't been recycled */
102 		e->state = SMT_STATE_UNUSED;
103 	}
104 	spin_unlock_bh(&e->lock);
105 }
106 
107 /**
108  * @e: smt entry to release
109  *
110  * Releases ref count and frees up an smt entry from SMT table
111  */
112 void cxgb4_smt_release(struct smt_entry *e)
113 {
114 	if (atomic_dec_and_test(&e->refcnt))
115 		t4_smte_free(e);
116 }
117 EXPORT_SYMBOL(cxgb4_smt_release);
118 
119 void do_smt_write_rpl(struct adapter *adap, const struct cpl_smt_write_rpl *rpl)
120 {
121 	unsigned int smtidx = TID_TID_G(GET_TID(rpl));
122 	struct smt_data *s = adap->smt;
123 
124 	if (unlikely(rpl->status != CPL_ERR_NONE)) {
125 		struct smt_entry *e = &s->smtab[smtidx];
126 
127 		dev_err(adap->pdev_dev,
128 			"Unexpected SMT_WRITE_RPL status %u for entry %u\n",
129 			rpl->status, smtidx);
130 		spin_lock(&e->lock);
131 		e->state = SMT_STATE_ERROR;
132 		spin_unlock(&e->lock);
133 		return;
134 	}
135 }
136 
137 static int write_smt_entry(struct adapter *adapter, struct smt_entry *e)
138 {
139 	struct cpl_t6_smt_write_req *t6req;
140 	struct smt_data *s = adapter->smt;
141 	struct cpl_smt_write_req *req;
142 	struct sk_buff *skb;
143 	int size;
144 	u8 row;
145 
146 	if (CHELSIO_CHIP_VERSION(adapter->params.chip) <= CHELSIO_T5) {
147 		size = sizeof(*req);
148 		skb = alloc_skb(size, GFP_ATOMIC);
149 		if (!skb)
150 			return -ENOMEM;
151 		/* Source MAC Table (SMT) contains 256 SMAC entries
152 		 * organized in 128 rows of 2 entries each.
153 		 */
154 		req = (struct cpl_smt_write_req *)__skb_put(skb, size);
155 		INIT_TP_WR(req, 0);
156 
157 		/* Each row contains an SMAC pair.
158 		 * LSB selects the SMAC entry within a row
159 		 */
160 		row = (e->idx >> 1);
161 		if (e->idx & 1) {
162 			req->pfvf1 = 0x0;
163 			memcpy(req->src_mac1, e->src_mac, ETH_ALEN);
164 
165 			/* fill pfvf0/src_mac0 with entry
166 			 * at prev index from smt-tab.
167 			 */
168 			req->pfvf0 = 0x0;
169 			memcpy(req->src_mac0, s->smtab[e->idx - 1].src_mac,
170 			       ETH_ALEN);
171 		} else {
172 			req->pfvf0 = 0x0;
173 			memcpy(req->src_mac0, e->src_mac, ETH_ALEN);
174 
175 			/* fill pfvf1/src_mac1 with entry
176 			 * at next index from smt-tab
177 			 */
178 			req->pfvf1 = 0x0;
179 			memcpy(req->src_mac1, s->smtab[e->idx + 1].src_mac,
180 			       ETH_ALEN);
181 		}
182 	} else {
183 		size = sizeof(*t6req);
184 		skb = alloc_skb(size, GFP_ATOMIC);
185 		if (!skb)
186 			return -ENOMEM;
187 		/* Source MAC Table (SMT) contains 256 SMAC entries */
188 		t6req = (struct cpl_t6_smt_write_req *)__skb_put(skb, size);
189 		INIT_TP_WR(t6req, 0);
190 		req = (struct cpl_smt_write_req *)t6req;
191 
192 		/* fill pfvf0/src_mac0 from smt-tab */
193 		req->pfvf0 = 0x0;
194 		memcpy(req->src_mac0, s->smtab[e->idx].src_mac, ETH_ALEN);
195 		row = e->idx;
196 	}
197 
198 	OPCODE_TID(req) =
199 		htonl(MK_OPCODE_TID(CPL_SMT_WRITE_REQ, e->idx |
200 				    TID_QID_V(adapter->sge.fw_evtq.abs_id)));
201 	req->params = htonl(SMTW_NORPL_V(0) |
202 			    SMTW_IDX_V(row) |
203 			    SMTW_OVLAN_IDX_V(0));
204 	t4_mgmt_tx(adapter, skb);
205 	return 0;
206 }
207 
208 static struct smt_entry *t4_smt_alloc_switching(struct adapter *adap, u16 pfvf,
209 						u8 *smac)
210 {
211 	struct smt_data *s = adap->smt;
212 	struct smt_entry *e;
213 
214 	write_lock_bh(&s->lock);
215 	e = find_or_alloc_smte(s, smac);
216 	if (e) {
217 		spin_lock(&e->lock);
218 		if (!atomic_read(&e->refcnt)) {
219 			atomic_set(&e->refcnt, 1);
220 			e->state = SMT_STATE_SWITCHING;
221 			e->pfvf = pfvf;
222 			memcpy(e->src_mac, smac, ETH_ALEN);
223 			write_smt_entry(adap, e);
224 		} else {
225 			atomic_inc(&e->refcnt);
226 		}
227 		spin_unlock(&e->lock);
228 	}
229 	write_unlock_bh(&s->lock);
230 	return e;
231 }
232 
233 /**
234  * @dev: net_device pointer
235  * @smac: MAC address to add to SMT
236  * Returns pointer to the SMT entry created
237  *
238  * Allocates an SMT entry to be used by switching rule of a filter.
239  */
240 struct smt_entry *cxgb4_smt_alloc_switching(struct net_device *dev, u8 *smac)
241 {
242 	struct adapter *adap = netdev2adap(dev);
243 
244 	return t4_smt_alloc_switching(adap, 0x0, smac);
245 }
246 EXPORT_SYMBOL(cxgb4_smt_alloc_switching);
247