sys/dev/netmap/if_lem_netmap.h

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (C) 2011-2014 Matteo Landi, Luigi Rizzo. All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  */
  27
  28
  29 /*
  30  * $FreeBSD$
  31  *
  32  * netmap support for: lem
  33  *
  34  * For details on netmap support please see ixgbe_netmap.h
  35  */
  36
  37
  38 #include <net/netmap.h>
  39 #include <sys/selinfo.h>
  40 #include <dev/netmap/netmap_kern.h>
  41
  42 /*
  43  * Register/unregister. We are already under netmap lock.
  44  */
  45 static int
  46 lem_netmap_reg(struct netmap_adapter *na, int onoff)
  47 {
  48         struct ifnet *ifp = na->ifp;
  49         struct adapter *adapter = ifp->if_softc;
  50
  51         EM_CORE_LOCK(adapter);
  52
  53         lem_disable_intr(adapter);
  54
  55         /* Tell the stack that the interface is no longer active */
  56         ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
  57
  58 #ifndef EM_LEGACY_IRQ // XXX do we need this ?
  59         taskqueue_block(adapter->tq);
  60         taskqueue_drain(adapter->tq, &adapter->rxtx_task);
  61         taskqueue_drain(adapter->tq, &adapter->link_task);
  62 #endif /* !EM_LEGCY_IRQ */
  63
  64         /* enable or disable flags and callbacks in na and ifp */
  65         if (onoff) {
  66                 nm_set_native_flags(na);
  67         } else {
  68                 nm_clear_native_flags(na);
  69         }
  70         lem_init_locked(adapter);       /* also enable intr */
  71
  72 #ifndef EM_LEGACY_IRQ
  73         taskqueue_unblock(adapter->tq); // XXX do we need this ?
  74 #endif /* !EM_LEGCY_IRQ */
  75
  76         EM_CORE_UNLOCK(adapter);
  77
  78         return (ifp->if_drv_flags & IFF_DRV_RUNNING ? 0 : 1);
  79 }
  80
  81
  82 static void
  83 lem_netmap_intr(struct netmap_adapter *na, int onoff)
  84 {
  85         struct ifnet *ifp = na->ifp;
  86         struct adapter *adapter = ifp->if_softc;
  87
  88         EM_CORE_LOCK(adapter);
  89         if (onoff) {
  90                 lem_enable_intr(adapter);
  91         } else {
  92                 lem_disable_intr(adapter);
  93         }
  94         EM_CORE_UNLOCK(adapter);
  95 }
  96
  97
  98 /*
  99  * Reconcile kernel and user view of the transmit ring.
 100  */
 101 static int
 102 lem_netmap_txsync(struct netmap_kring *kring, int flags)
 103 {
 104         struct netmap_adapter *na = kring->na;
 105         struct ifnet *ifp = na->ifp;
 106         struct netmap_ring *ring = kring->ring;
 107         u_int nm_i;     /* index into the netmap ring */
 108         u_int nic_i;    /* index into the NIC ring */
 109         u_int const lim = kring->nkr_num_slots - 1;
 110         u_int const head = kring->rhead;
 111         /* generate an interrupt approximately every half ring */
 112         u_int report_frequency = kring->nkr_num_slots >> 1;
 113
 114         /* device-specific */
 115         struct adapter *adapter = ifp->if_softc;
 116
 117         bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
 118                         BUS_DMASYNC_POSTREAD);
 119
 120         /*
 121          * First part: process new packets to send.
 122          */
 123
 124         nm_i = kring->nr_hwcur;
 125         if (nm_i != head) {     /* we have new packets to send */
 126                 nic_i = netmap_idx_k2n(kring, nm_i);
 127                 while (nm_i != head) {
 128                         struct netmap_slot *slot = &ring->slot[nm_i];
 129                         u_int len = slot->len;
 130                         uint64_t paddr;
 131                         void *addr = PNMB(na, slot, &paddr);
 132
 133                         /* device-specific */
 134                         struct e1000_tx_desc *curr = &adapter->tx_desc_base[nic_i];
 135                         struct em_buffer *txbuf = &adapter->tx_buffer_area[nic_i];
 136                         int flags = (slot->flags & NS_REPORT ||
 137                                 nic_i == 0 || nic_i == report_frequency) ?
 138                                 E1000_TXD_CMD_RS : 0;
 139
 140                         NM_CHECK_ADDR_LEN(na, addr, len);
 141
 142                         if (slot->flags & NS_BUF_CHANGED) {
 143                                 /* buffer has changed, reload map */
 144                                 curr->buffer_addr = htole64(paddr);
 145                                 netmap_reload_map(na, adapter->txtag, txbuf->map, addr);
 146                         }
 147                         slot->flags &= ~(NS_REPORT | NS_BUF_CHANGED);
 148
 149                         /* Fill the slot in the NIC ring. */
 150                         curr->upper.data = 0;
 151                         curr->lower.data = htole32(adapter->txd_cmd | len |
 152                                 (E1000_TXD_CMD_EOP | flags) );
 153                         bus_dmamap_sync(adapter->txtag, txbuf->map,
 154                                 BUS_DMASYNC_PREWRITE);
 155
 156                         nm_i = nm_next(nm_i, lim);
 157                         nic_i = nm_next(nic_i, lim);
 158                         // XXX might try an early kick
 159                 }
 160                 kring->nr_hwcur = head;
 161
 162                  /* synchronize the NIC ring */
 163                 bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
 164                         BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 165
 166                 /* (re)start the tx unit up to slot nic_i (excluded) */
 167                 E1000_WRITE_REG(&adapter->hw, E1000_TDT(0), nic_i);
 168         }
 169
 170         /*
 171          * Second part: reclaim buffers for completed transmissions.
 172          */
 173         if (ticks != kring->last_reclaim || flags & NAF_FORCE_RECLAIM || nm_kr_txempty(kring)) {
 174                 kring->last_reclaim = ticks;
 175                 /* record completed transmissions using TDH */
 176                 nic_i = E1000_READ_REG(&adapter->hw, E1000_TDH(0));
 177                 if (nic_i >= kring->nkr_num_slots) { /* XXX can it happen ? */
 178                         D("TDH wrap %d", nic_i);
 179                         nic_i -= kring->nkr_num_slots;
 180                 }
 181                 adapter->next_tx_to_clean = nic_i;
 182                 kring->nr_hwtail = nm_prev(netmap_idx_n2k(kring, nic_i), lim);
 183         }
 184
 185         return 0;
 186 }
 187
 188
 189 /*
 190  * Reconcile kernel and user view of the receive ring.
 191  */
 192 static int
 193 lem_netmap_rxsync(struct netmap_kring *kring, int flags)
 194 {
 195         struct netmap_adapter *na = kring->na;
 196         struct ifnet *ifp = na->ifp;
 197         struct netmap_ring *ring = kring->ring;
 198         u_int nm_i;     /* index into the netmap ring */
 199         u_int nic_i;    /* index into the NIC ring */
 200         u_int n;
 201         u_int const lim = kring->nkr_num_slots - 1;
 202         u_int const head = kring->rhead;
 203         int force_update = (flags & NAF_FORCE_READ) || kring->nr_kflags & NKR_PENDINTR;
 204
 205         /* device-specific */
 206         struct adapter *adapter = ifp->if_softc;
 207
 208         if (head > lim)
 209                 return netmap_ring_reinit(kring);
 210
 211         /* XXX check sync modes */
 212         bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
 213                         BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
 214
 215         /*
 216          * First part: import newly received packets.
 217          */
 218         if (netmap_no_pendintr || force_update) {
 219                 nic_i = adapter->next_rx_desc_to_check;
 220                 nm_i = netmap_idx_n2k(kring, nic_i);
 221
 222                 for (n = 0; ; n++) {
 223                         struct e1000_rx_desc *curr = &adapter->rx_desc_base[nic_i];
 224                         uint32_t staterr = le32toh(curr->status);
 225                         int len;
 226
 227                         if ((staterr & E1000_RXD_STAT_DD) == 0)
 228                                 break;
 229                         len = le16toh(curr->length) - 4; // CRC
 230                         if (len < 0) {
 231                                 RD(5, "bogus pkt (%d) size %d nic idx %d", n, len, nic_i);
 232                                 len = 0;
 233                         }
 234                         ring->slot[nm_i].len = len;
 235                         ring->slot[nm_i].flags = 0;
 236                         bus_dmamap_sync(adapter->rxtag,
 237                                 adapter->rx_buffer_area[nic_i].map,
 238                                 BUS_DMASYNC_POSTREAD);
 239                         nm_i = nm_next(nm_i, lim);
 240                         nic_i = nm_next(nic_i, lim);
 241                 }
 242                 if (n) { /* update the state variables */
 243                         ND("%d new packets at nic %d nm %d tail %d",
 244                                 n,
 245                                 adapter->next_rx_desc_to_check,
 246                                 netmap_idx_n2k(kring, adapter->next_rx_desc_to_check),
 247                                 kring->nr_hwtail);
 248                         adapter->next_rx_desc_to_check = nic_i;
 249                         // if_inc_counter(ifp, IFCOUNTER_IPACKETS, n);
 250                         kring->nr_hwtail = nm_i;
 251                 }
 252                 kring->nr_kflags &= ~NKR_PENDINTR;
 253         }
 254
 255         /*
 256          * Second part: skip past packets that userspace has released.
 257          */
 258         nm_i = kring->nr_hwcur;
 259         if (nm_i != head) {
 260                 nic_i = netmap_idx_k2n(kring, nm_i);
 261                 for (n = 0; nm_i != head; n++) {
 262                         struct netmap_slot *slot = &ring->slot[nm_i];
 263                         uint64_t paddr;
 264                         void *addr = PNMB(na, slot, &paddr);
 265
 266                         struct e1000_rx_desc *curr = &adapter->rx_desc_base[nic_i];
 267                         struct em_buffer *rxbuf = &adapter->rx_buffer_area[nic_i];
 268
 269                         if (addr == NETMAP_BUF_BASE(na)) /* bad buf */
 270                                 goto ring_reset;
 271
 272                         if (slot->flags & NS_BUF_CHANGED) {
 273                                 /* buffer has changed, reload map */
 274                                 curr->buffer_addr = htole64(paddr);
 275                                 netmap_reload_map(na, adapter->rxtag, rxbuf->map, addr);
 276                                 slot->flags &= ~NS_BUF_CHANGED;
 277                         }
 278                         curr->status = 0;
 279                         bus_dmamap_sync(adapter->rxtag, rxbuf->map,
 280                             BUS_DMASYNC_PREREAD);
 281                         nm_i = nm_next(nm_i, lim);
 282                         nic_i = nm_next(nic_i, lim);
 283                 }
 284                 kring->nr_hwcur = head;
 285                 bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
 286                     BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 287                 /*
 288                  * IMPORTANT: we must leave one free slot in the ring,
 289                  * so move nic_i back by one unit
 290                  */
 291                 nic_i = nm_prev(nic_i, lim);
 292                 E1000_WRITE_REG(&adapter->hw, E1000_RDT(0), nic_i);
 293         }
 294
 295         return 0;
 296
 297 ring_reset:
 298         return netmap_ring_reinit(kring);
 299 }
 300
 301
 302 static void
 303 lem_netmap_attach(struct adapter *adapter)
 304 {
 305         struct netmap_adapter na;
 306
 307         bzero(&na, sizeof(na));
 308
 309         na.ifp = adapter->ifp;
 310         na.na_flags = NAF_BDG_MAYSLEEP;
 311         na.num_tx_desc = adapter->num_tx_desc;
 312         na.num_rx_desc = adapter->num_rx_desc;
 313         na.nm_txsync = lem_netmap_txsync;
 314         na.nm_rxsync = lem_netmap_rxsync;
 315         na.nm_register = lem_netmap_reg;
 316         na.num_tx_rings = na.num_rx_rings = 1;
 317         na.nm_intr = lem_netmap_intr;
 318         netmap_attach(&na);
 319 }
 320
 321 /* end of file */