sys/dev/netmap/if_lem_netmap.h

   1 /*
   2  * Copyright (C) 2011-2014 Matteo Landi, Luigi Rizzo. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  23  * SUCH DAMAGE.
  24  */
  25
  26
  27 /*
  28  * $FreeBSD$
  29  *
  30  * netmap support for: lem
  31  *
  32  * For details on netmap support please see ixgbe_netmap.h
  33  */
  34
  35
  36 #include <net/netmap.h>
  37 #include <sys/selinfo.h>
  38 #include <vm/vm.h>
  39 #include <vm/pmap.h>    /* vtophys ? */
  40 #include <dev/netmap/netmap_kern.h>
  41
  42
  43 /*
  44  * Register/unregister. We are already under netmap lock.
  45  */
  46 static int
  47 lem_netmap_reg(struct netmap_adapter *na, int onoff)
  48 {
  49         struct ifnet *ifp = na->ifp;
  50         struct adapter *adapter = ifp->if_softc;
  51
  52         EM_CORE_LOCK(adapter);
  53
  54         lem_disable_intr(adapter);
  55
  56         /* Tell the stack that the interface is no longer active */
  57         ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
  58
  59 #ifndef EM_LEGACY_IRQ // XXX do we need this ?
  60         taskqueue_block(adapter->tq);
  61         taskqueue_drain(adapter->tq, &adapter->rxtx_task);
  62         taskqueue_drain(adapter->tq, &adapter->link_task);
  63 #endif /* !EM_LEGCY_IRQ */
  64
  65         /* enable or disable flags and callbacks in na and ifp */
  66         if (onoff) {
  67                 nm_set_native_flags(na);
  68         } else {
  69                 nm_clear_native_flags(na);
  70         }
  71         lem_init_locked(adapter);       /* also enable intr */
  72
  73 #ifndef EM_LEGACY_IRQ
  74         taskqueue_unblock(adapter->tq); // XXX do we need this ?
  75 #endif /* !EM_LEGCY_IRQ */
  76
  77         EM_CORE_UNLOCK(adapter);
  78
  79         return (ifp->if_drv_flags & IFF_DRV_RUNNING ? 0 : 1);
  80 }
  81
  82
  83 /*
  84  * Reconcile kernel and user view of the transmit ring.
  85  */
  86 static int
  87 lem_netmap_txsync(struct netmap_adapter *na, u_int ring_nr, int flags)
  88 {
  89         struct ifnet *ifp = na->ifp;
  90         struct netmap_kring *kring = &na->tx_rings[ring_nr];
  91         struct netmap_ring *ring = kring->ring;
  92         u_int nm_i;     /* index into the netmap ring */
  93         u_int nic_i;    /* index into the NIC ring */
  94         u_int const lim = kring->nkr_num_slots - 1;
  95         u_int const head = kring->rhead;
  96         /* generate an interrupt approximately every half ring */
  97         u_int report_frequency = kring->nkr_num_slots >> 1;
  98
  99         /* device-specific */
 100         struct adapter *adapter = ifp->if_softc;
 101
 102         bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
 103                         BUS_DMASYNC_POSTREAD);
 104
 105         /*
 106          * First part: process new packets to send.
 107          */
 108
 109         nm_i = kring->nr_hwcur;
 110         if (nm_i != head) {     /* we have new packets to send */
 111                 nic_i = netmap_idx_k2n(kring, nm_i);
 112                 while (nm_i != head) {
 113                         struct netmap_slot *slot = &ring->slot[nm_i];
 114                         u_int len = slot->len;
 115                         uint64_t paddr;
 116                         void *addr = PNMB(slot, &paddr);
 117
 118                         /* device-specific */
 119                         struct e1000_tx_desc *curr = &adapter->tx_desc_base[nic_i];
 120                         struct em_buffer *txbuf = &adapter->tx_buffer_area[nic_i];
 121                         int flags = (slot->flags & NS_REPORT ||
 122                                 nic_i == 0 || nic_i == report_frequency) ?
 123                                 E1000_TXD_CMD_RS : 0;
 124
 125                         NM_CHECK_ADDR_LEN(addr, len);
 126
 127                         if (slot->flags & NS_BUF_CHANGED) {
 128                                 /* buffer has changed, reload map */
 129                                 curr->buffer_addr = htole64(paddr);
 130                                 netmap_reload_map(adapter->txtag, txbuf->map, addr);
 131                         }
 132                         slot->flags &= ~(NS_REPORT | NS_BUF_CHANGED);
 133
 134                         /* Fill the slot in the NIC ring. */
 135                         curr->upper.data = 0;
 136                         curr->lower.data = htole32(adapter->txd_cmd | len |
 137                                 (E1000_TXD_CMD_EOP | flags) );
 138                         bus_dmamap_sync(adapter->txtag, txbuf->map,
 139                                 BUS_DMASYNC_PREWRITE);
 140
 141                         nm_i = nm_next(nm_i, lim);
 142                         nic_i = nm_next(nic_i, lim);
 143                 }
 144                 kring->nr_hwcur = head;
 145
 146                  /* synchronize the NIC ring */
 147                 bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
 148                         BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 149
 150                 /* (re)start the tx unit up to slot nic_i (excluded) */
 151                 E1000_WRITE_REG(&adapter->hw, E1000_TDT(0), nic_i);
 152         }
 153
 154         /*
 155          * Second part: reclaim buffers for completed transmissions.
 156          */
 157         if (ticks != kring->last_reclaim || flags & NAF_FORCE_RECLAIM || nm_kr_txempty(kring)) {
 158                 kring->last_reclaim = ticks;
 159                 /* record completed transmissions using TDH */
 160                 nic_i = E1000_READ_REG(&adapter->hw, E1000_TDH(0));
 161                 if (nic_i >= kring->nkr_num_slots) { /* XXX can it happen ? */
 162                         D("TDH wrap %d", nic_i);
 163                         nic_i -= kring->nkr_num_slots;
 164                 }
 165                 adapter->next_tx_to_clean = nic_i;
 166                 kring->nr_hwtail = nm_prev(netmap_idx_n2k(kring, nic_i), lim);
 167         }
 168
 169         nm_txsync_finalize(kring);
 170
 171         return 0;
 172 }
 173
 174
 175 /*
 176  * Reconcile kernel and user view of the receive ring.
 177  */
 178 static int
 179 lem_netmap_rxsync(struct netmap_adapter *na, u_int ring_nr, int flags)
 180 {
 181         struct ifnet *ifp = na->ifp;
 182         struct netmap_kring *kring = &na->rx_rings[ring_nr];
 183         struct netmap_ring *ring = kring->ring;
 184         u_int nm_i;     /* index into the netmap ring */
 185         u_int nic_i;    /* index into the NIC ring */
 186         u_int n;
 187         u_int const lim = kring->nkr_num_slots - 1;
 188         u_int const head = nm_rxsync_prologue(kring);
 189         int force_update = (flags & NAF_FORCE_READ) || kring->nr_kflags & NKR_PENDINTR;
 190
 191         /* device-specific */
 192         struct adapter *adapter = ifp->if_softc;
 193
 194         if (head > lim)
 195                 return netmap_ring_reinit(kring);
 196
 197         /* XXX check sync modes */
 198         bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
 199                         BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
 200
 201         /*
 202          * First part: import newly received packets.
 203          */
 204         if (netmap_no_pendintr || force_update) {
 205                 uint16_t slot_flags = kring->nkr_slot_flags;
 206
 207                 nic_i = adapter->next_rx_desc_to_check;
 208                 nm_i = netmap_idx_n2k(kring, nic_i);
 209
 210                 for (n = 0; ; n++) {
 211                         struct e1000_rx_desc *curr = &adapter->rx_desc_base[nic_i];
 212                         uint32_t staterr = le32toh(curr->status);
 213                         int len;
 214
 215                         if ((staterr & E1000_RXD_STAT_DD) == 0)
 216                                 break;
 217                         len = le16toh(curr->length) - 4; // CRC
 218                         if (len < 0) {
 219                                 D("bogus pkt size %d nic idx %d", len, nic_i);
 220                                 len = 0;
 221                         }
 222                         ring->slot[nm_i].len = len;
 223                         ring->slot[nm_i].flags = slot_flags;
 224                         bus_dmamap_sync(adapter->rxtag,
 225                                 adapter->rx_buffer_area[nic_i].map,
 226                                 BUS_DMASYNC_POSTREAD);
 227                         nm_i = nm_next(nm_i, lim);
 228                         nic_i = nm_next(nic_i, lim);
 229                 }
 230                 if (n) { /* update the state variables */
 231                         ND("%d new packets at nic %d nm %d tail %d",
 232                                 n,
 233                                 adapter->next_rx_desc_to_check,
 234                                 netmap_idx_n2k(kring, adapter->next_rx_desc_to_check),
 235                                 kring->nr_hwtail);
 236                         adapter->next_rx_desc_to_check = nic_i;
 237                         // ifp->if_ipackets += n;
 238                         kring->nr_hwtail = nm_i;
 239                 }
 240                 kring->nr_kflags &= ~NKR_PENDINTR;
 241         }
 242
 243         /*
 244          * Second part: skip past packets that userspace has released.
 245          */
 246         nm_i = kring->nr_hwcur;
 247         if (nm_i != head) {
 248                 nic_i = netmap_idx_k2n(kring, nm_i);
 249                 for (n = 0; nm_i != head; n++) {
 250                         struct netmap_slot *slot = &ring->slot[nm_i];
 251                         uint64_t paddr;
 252                         void *addr = PNMB(slot, &paddr);
 253
 254                         struct e1000_rx_desc *curr = &adapter->rx_desc_base[nic_i];
 255                         struct em_buffer *rxbuf = &adapter->rx_buffer_area[nic_i];
 256
 257                         if (addr == netmap_buffer_base) /* bad buf */
 258                                 goto ring_reset;
 259
 260                         if (slot->flags & NS_BUF_CHANGED) {
 261                                 /* buffer has changed, reload map */
 262                                 curr->buffer_addr = htole64(paddr);
 263                                 netmap_reload_map(adapter->rxtag, rxbuf->map, addr);
 264                                 slot->flags &= ~NS_BUF_CHANGED;
 265                         }
 266                         curr->status = 0;
 267                         bus_dmamap_sync(adapter->rxtag, rxbuf->map,
 268                             BUS_DMASYNC_PREREAD);
 269                         nm_i = nm_next(nm_i, lim);
 270                         nic_i = nm_next(nic_i, lim);
 271                 }
 272                 kring->nr_hwcur = head;
 273                 bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
 274                     BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 275                 /*
 276                  * IMPORTANT: we must leave one free slot in the ring,
 277                  * so move nic_i back by one unit
 278                  */
 279                 nic_i = nm_prev(nic_i, lim);
 280                 E1000_WRITE_REG(&adapter->hw, E1000_RDT(0), nic_i);
 281         }
 282
 283         /* tell userspace that there might be new packets */
 284         nm_rxsync_finalize(kring);
 285
 286         return 0;
 287
 288 ring_reset:
 289         return netmap_ring_reinit(kring);
 290 }
 291
 292
 293 static void
 294 lem_netmap_attach(struct adapter *adapter)
 295 {
 296         struct netmap_adapter na;
 297
 298         bzero(&na, sizeof(na));
 299
 300         na.ifp = adapter->ifp;
 301         na.na_flags = NAF_BDG_MAYSLEEP;
 302         na.num_tx_desc = adapter->num_tx_desc;
 303         na.num_rx_desc = adapter->num_rx_desc;
 304         na.nm_txsync = lem_netmap_txsync;
 305         na.nm_rxsync = lem_netmap_rxsync;
 306         na.nm_register = lem_netmap_reg;
 307         na.num_tx_rings = na.num_rx_rings = 1;
 308         netmap_attach(&na);
 309 }
 310
 311 /* end of file */