drivers/net/ethernet/chelsio/cxgb4/smt.c

   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(sizeof(*s) + smt_size * sizeof(struct smt_entry),
  51                      GFP_KERNEL);
  52         if (!s)
  53                 return NULL;
  54         s->smt_size = smt_size;
  55         rwlock_init(&s->lock);
  56         for (i = 0; i < s->smt_size; ++i) {
  57                 s->smtab[i].idx = i;
  58                 s->smtab[i].state = SMT_STATE_UNUSED;
  59                 memset(&s->smtab[i].src_mac, 0, ETH_ALEN);
  60                 spin_lock_init(&s->smtab[i].lock);
  61                 atomic_set(&s->smtab[i].refcnt, 0);
  62         }
  63         return s;
  64 }
  65
  66 static struct smt_entry *find_or_alloc_smte(struct smt_data *s, u8 *smac)
  67 {
  68         struct smt_entry *first_free = NULL;
  69         struct smt_entry *e, *end;
  70
  71         for (e = &s->smtab[0], end = &s->smtab[s->smt_size]; e != end; ++e) {
  72                 if (atomic_read(&e->refcnt) == 0) {
  73                         if (!first_free)
  74                                 first_free = e;
  75                 } else {
  76                         if (e->state == SMT_STATE_SWITCHING) {
  77                                 /* This entry is actually in use. See if we can
  78                                  * re-use it ?
  79                                  */
  80                                 if (memcmp(e->src_mac, smac, ETH_ALEN) == 0)
  81                                         goto found_reuse;
  82                         }
  83                 }
  84         }
  85
  86         if (first_free) {
  87                 e = first_free;
  88                 goto found;
  89         }
  90         return NULL;
  91
  92 found:
  93         e->state = SMT_STATE_UNUSED;
  94
  95 found_reuse:
  96         return e;
  97 }
  98
  99 static void t4_smte_free(struct smt_entry *e)
 100 {
 101         if (atomic_read(&e->refcnt) == 0) {  /* hasn't been recycled */
 102                 e->state = SMT_STATE_UNUSED;
 103         }
 104 }
 105
 106 /**
 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 (atomic_dec_and_test(&e->refcnt))
 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 (!atomic_read(&e->refcnt)) {
 220                         atomic_set(&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                         atomic_inc(&e->refcnt);
 227                 }
 228                 spin_unlock(&e->lock);
 229         }
 230         write_unlock_bh(&s->lock);
 231         return e;
 232 }
 233
 234 /**
 235  * @dev: net_device pointer
 236  * @smac: MAC address to add to SMT
 237  * Returns pointer to the SMT entry created
 238  *
 239  * Allocates an SMT entry to be used by switching rule of a filter.
 240  */
 241 struct smt_entry *cxgb4_smt_alloc_switching(struct net_device *dev, u8 *smac)
 242 {
 243         struct adapter *adap = netdev2adap(dev);
 244
 245         return t4_smt_alloc_switching(adap, 0x0, smac);
 246 }
 247 EXPORT_SYMBOL(cxgb4_smt_alloc_switching);