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 		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 (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 	if (e->refcnt == 0) {  /* hasn't been recycled */
101 		e->state = SMT_STATE_UNUSED;
102 	}
103 }
104 
105 /**
106  * cxgb4_smt_release - Release SMT entry
107  * @e: smt entry to release
108  *
109  * Releases ref count and frees up an smt entry from SMT table
110  */
111 void cxgb4_smt_release(struct smt_entry *e)
112 {
113 	spin_lock_bh(&e->lock);
114 	if ((--e->refcnt) == 0)
115 		t4_smte_free(e);
116 	spin_unlock_bh(&e->lock);
117 }
118 EXPORT_SYMBOL(cxgb4_smt_release);
119 
120 void do_smt_write_rpl(struct adapter *adap, const struct cpl_smt_write_rpl *rpl)
121 {
122 	unsigned int smtidx = TID_TID_G(GET_TID(rpl));
123 	struct smt_data *s = adap->smt;
124 
125 	if (unlikely(rpl->status != CPL_ERR_NONE)) {
126 		struct smt_entry *e = &s->smtab[smtidx];
127 
128 		dev_err(adap->pdev_dev,
129 			"Unexpected SMT_WRITE_RPL status %u for entry %u\n",
130 			rpl->status, smtidx);
131 		spin_lock(&e->lock);
132 		e->state = SMT_STATE_ERROR;
133 		spin_unlock(&e->lock);
134 		return;
135 	}
136 }
137 
138 static int write_smt_entry(struct adapter *adapter, struct smt_entry *e)
139 {
140 	struct cpl_t6_smt_write_req *t6req;
141 	struct smt_data *s = adapter->smt;
142 	struct cpl_smt_write_req *req;
143 	struct sk_buff *skb;
144 	int size;
145 	u8 row;
146 
147 	if (CHELSIO_CHIP_VERSION(adapter->params.chip) <= CHELSIO_T5) {
148 		size = sizeof(*req);
149 		skb = alloc_skb(size, GFP_ATOMIC);
150 		if (!skb)
151 			return -ENOMEM;
152 		/* Source MAC Table (SMT) contains 256 SMAC entries
153 		 * organized in 128 rows of 2 entries each.
154 		 */
155 		req = (struct cpl_smt_write_req *)__skb_put(skb, size);
156 		INIT_TP_WR(req, 0);
157 
158 		/* Each row contains an SMAC pair.
159 		 * LSB selects the SMAC entry within a row
160 		 */
161 		row = (e->idx >> 1);
162 		if (e->idx & 1) {
163 			req->pfvf1 = 0x0;
164 			memcpy(req->src_mac1, e->src_mac, ETH_ALEN);
165 
166 			/* fill pfvf0/src_mac0 with entry
167 			 * at prev index from smt-tab.
168 			 */
169 			req->pfvf0 = 0x0;
170 			memcpy(req->src_mac0, s->smtab[e->idx - 1].src_mac,
171 			       ETH_ALEN);
172 		} else {
173 			req->pfvf0 = 0x0;
174 			memcpy(req->src_mac0, e->src_mac, ETH_ALEN);
175 
176 			/* fill pfvf1/src_mac1 with entry
177 			 * at next index from smt-tab
178 			 */
179 			req->pfvf1 = 0x0;
180 			memcpy(req->src_mac1, s->smtab[e->idx + 1].src_mac,
181 			       ETH_ALEN);
182 		}
183 	} else {
184 		size = sizeof(*t6req);
185 		skb = alloc_skb(size, GFP_ATOMIC);
186 		if (!skb)
187 			return -ENOMEM;
188 		/* Source MAC Table (SMT) contains 256 SMAC entries */
189 		t6req = (struct cpl_t6_smt_write_req *)__skb_put(skb, size);
190 		INIT_TP_WR(t6req, 0);
191 		req = (struct cpl_smt_write_req *)t6req;
192 
193 		/* fill pfvf0/src_mac0 from smt-tab */
194 		req->pfvf0 = 0x0;
195 		memcpy(req->src_mac0, s->smtab[e->idx].src_mac, ETH_ALEN);
196 		row = e->idx;
197 	}
198 
199 	OPCODE_TID(req) =
200 		htonl(MK_OPCODE_TID(CPL_SMT_WRITE_REQ, e->idx |
201 				    TID_QID_V(adapter->sge.fw_evtq.abs_id)));
202 	req->params = htonl(SMTW_NORPL_V(0) |
203 			    SMTW_IDX_V(row) |
204 			    SMTW_OVLAN_IDX_V(0));
205 	t4_mgmt_tx(adapter, skb);
206 	return 0;
207 }
208 
209 static struct smt_entry *t4_smt_alloc_switching(struct adapter *adap, u16 pfvf,
210 						u8 *smac)
211 {
212 	struct smt_data *s = adap->smt;
213 	struct smt_entry *e;
214 
215 	write_lock_bh(&s->lock);
216 	e = find_or_alloc_smte(s, smac);
217 	if (e) {
218 		spin_lock(&e->lock);
219 		if (!e->refcnt) {
220 			e->refcnt = 1;
221 			e->state = SMT_STATE_SWITCHING;
222 			e->pfvf = pfvf;
223 			memcpy(e->src_mac, smac, ETH_ALEN);
224 			write_smt_entry(adap, e);
225 		} else {
226 			++e->refcnt;
227 		}
228 		spin_unlock(&e->lock);
229 	}
230 	write_unlock_bh(&s->lock);
231 	return e;
232 }
233 
234 /**
235  * cxgb4_smt_alloc_switching - Allocates an SMT entry for switch filters.
236  * @dev: net_device pointer
237  * @smac: MAC address to add to SMT
238  * Returns pointer to the SMT entry created
239  *
240  * Allocates an SMT entry to be used by switching rule of a filter.
241  */
242 struct smt_entry *cxgb4_smt_alloc_switching(struct net_device *dev, u8 *smac)
243 {
244 	struct adapter *adap = netdev2adap(dev);
245 
246 	return t4_smt_alloc_switching(adap, 0x0, smac);
247 }
248 EXPORT_SYMBOL(cxgb4_smt_alloc_switching);
249