drivers/net/tulip/interrupt.c

   1 /*
   2         drivers/net/tulip/interrupt.c
   3
   4         Copyright 2000,2001  The Linux Kernel Team
   5         Written/copyright 1994-2001 by Donald Becker.
   6
   7         This software may be used and distributed according to the terms
   8         of the GNU General Public License, incorporated herein by reference.
   9
  10         Please refer to Documentation/DocBook/tulip-user.{pdf,ps,html}
  11         for more information on this driver.
  12         Please submit bugs to http://bugzilla.kernel.org/ .
  13
  14 */
  15
  16 #include <linux/pci.h>
  17 #include "tulip.h"
  18 #include <linux/etherdevice.h>
  19
  20 int tulip_rx_copybreak;
  21 unsigned int tulip_max_interrupt_work;
  22
  23 #ifdef CONFIG_TULIP_NAPI_HW_MITIGATION
  24 #define MIT_SIZE 15
  25 #define MIT_TABLE 15 /* We use 0 or max */
  26
  27 static unsigned int mit_table[MIT_SIZE+1] =
  28 {
  29         /*  CRS11 21143 hardware Mitigation Control Interrupt
  30             We use only RX mitigation we other techniques for
  31             TX intr. mitigation.
  32
  33            31    Cycle Size (timer control)
  34            30:27 TX timer in 16 * Cycle size
  35            26:24 TX No pkts before Int.
  36            23:20 RX timer in Cycle size
  37            19:17 RX No pkts before Int.
  38            16       Continues Mode (CM)
  39         */
  40
  41         0x0,             /* IM disabled */
  42         0x80150000,      /* RX time = 1, RX pkts = 2, CM = 1 */
  43         0x80150000,
  44         0x80270000,
  45         0x80370000,
  46         0x80490000,
  47         0x80590000,
  48         0x80690000,
  49         0x807B0000,
  50         0x808B0000,
  51         0x809D0000,
  52         0x80AD0000,
  53         0x80BD0000,
  54         0x80CF0000,
  55         0x80DF0000,
  56 //       0x80FF0000      /* RX time = 16, RX pkts = 7, CM = 1 */
  57         0x80F10000      /* RX time = 16, RX pkts = 0, CM = 1 */
  58 };
  59 #endif
  60
  61
  62 int tulip_refill_rx(struct net_device *dev)
  63 {
  64         struct tulip_private *tp = netdev_priv(dev);
  65         int entry;
  66         int refilled = 0;
  67
  68         /* Refill the Rx ring buffers. */
  69         for (; tp->cur_rx - tp->dirty_rx > 0; tp->dirty_rx++) {
  70                 entry = tp->dirty_rx % RX_RING_SIZE;
  71                 if (tp->rx_buffers[entry].skb == NULL) {
  72                         struct sk_buff *skb;
  73                         dma_addr_t mapping;
  74
  75                         skb = tp->rx_buffers[entry].skb = dev_alloc_skb(PKT_BUF_SZ);
  76                         if (skb == NULL)
  77                                 break;
  78
  79                         mapping = pci_map_single(tp->pdev, skb->data, PKT_BUF_SZ,
  80                                                  PCI_DMA_FROMDEVICE);
  81                         tp->rx_buffers[entry].mapping = mapping;
  82
  83                         skb->dev = dev;                 /* Mark as being used by this device. */
  84                         tp->rx_ring[entry].buffer1 = cpu_to_le32(mapping);
  85                         refilled++;
  86                 }
  87                 tp->rx_ring[entry].status = cpu_to_le32(DescOwned);
  88         }
  89         if(tp->chip_id == LC82C168) {
  90                 if(((ioread32(tp->base_addr + CSR5)>>17)&0x07) == 4) {
  91                         /* Rx stopped due to out of buffers,
  92                          * restart it
  93                          */
  94                         iowrite32(0x01, tp->base_addr + CSR2);
  95                 }
  96         }
  97         return refilled;
  98 }
  99
 100 #ifdef CONFIG_TULIP_NAPI
 101
 102 void oom_timer(unsigned long data)
 103 {
 104         struct net_device *dev = (struct net_device *)data;
 105         struct tulip_private *tp = netdev_priv(dev);
 106         napi_schedule(&tp->napi);
 107 }
 108
 109 int tulip_poll(struct napi_struct *napi, int budget)
 110 {
 111         struct tulip_private *tp = container_of(napi, struct tulip_private, napi);
 112         struct net_device *dev = tp->dev;
 113         int entry = tp->cur_rx % RX_RING_SIZE;
 114         int work_done = 0;
 115 #ifdef CONFIG_TULIP_NAPI_HW_MITIGATION
 116         int received = 0;
 117 #endif
 118
 119 #ifdef CONFIG_TULIP_NAPI_HW_MITIGATION
 120
 121 /* that one buffer is needed for mit activation; or might be a
 122    bug in the ring buffer code; check later -- JHS*/
 123
 124         if (budget >=RX_RING_SIZE) budget--;
 125 #endif
 126
 127         if (tulip_debug > 4)
 128                 netdev_dbg(dev, " In tulip_rx(), entry %d %08x\n",
 129                            entry, tp->rx_ring[entry].status);
 130
 131        do {
 132                 if (ioread32(tp->base_addr + CSR5) == 0xffffffff) {
 133                         netdev_dbg(dev, " In tulip_poll(), hardware disappeared\n");
 134                         break;
 135                 }
 136                /* Acknowledge current RX interrupt sources. */
 137                iowrite32((RxIntr | RxNoBuf), tp->base_addr + CSR5);
 138
 139
 140                /* If we own the next entry, it is a new packet. Send it up. */
 141                while ( ! (tp->rx_ring[entry].status & cpu_to_le32(DescOwned))) {
 142                        s32 status = le32_to_cpu(tp->rx_ring[entry].status);
 143                        short pkt_len;
 144
 145                        if (tp->dirty_rx + RX_RING_SIZE == tp->cur_rx)
 146                                break;
 147
 148                        if (tulip_debug > 5)
 149                                 netdev_dbg(dev, "In tulip_rx(), entry %d %08x\n",
 150                                            entry, status);
 151
 152                        if (++work_done >= budget)
 153                                goto not_done;
 154
 155                        /*
 156                         * Omit the four octet CRC from the length.
 157                         * (May not be considered valid until we have
 158                         * checked status for RxLengthOver2047 bits)
 159                         */
 160                        pkt_len = ((status >> 16) & 0x7ff) - 4;
 161
 162                        /*
 163                         * Maximum pkt_len is 1518 (1514 + vlan header)
 164                         * Anything higher than this is always invalid
 165                         * regardless of RxLengthOver2047 bits
 166                         */
 167
 168                        if ((status & (RxLengthOver2047 |
 169                                       RxDescCRCError |
 170                                       RxDescCollisionSeen |
 171                                       RxDescRunt |
 172                                       RxDescDescErr |
 173                                       RxWholePkt)) != RxWholePkt ||
 174                            pkt_len > 1518) {
 175                                if ((status & (RxLengthOver2047 |
 176                                               RxWholePkt)) != RxWholePkt) {
 177                                 /* Ingore earlier buffers. */
 178                                        if ((status & 0xffff) != 0x7fff) {
 179                                                if (tulip_debug > 1)
 180                                                        dev_warn(&dev->dev,
 181                                                                 "Oversized Ethernet frame spanned multiple buffers, status %08x!\n",
 182                                                                 status);
 183                                                 dev->stats.rx_length_errors++;
 184                                         }
 185                                } else {
 186                                 /* There was a fatal error. */
 187                                        if (tulip_debug > 2)
 188                                                 netdev_dbg(dev, "Receive error, Rx status %08x\n",
 189                                                            status);
 190                                         dev->stats.rx_errors++; /* end of a packet.*/
 191                                         if (pkt_len > 1518 ||
 192                                             (status & RxDescRunt))
 193                                                 dev->stats.rx_length_errors++;
 194
 195                                         if (status & 0x0004)
 196                                                 dev->stats.rx_frame_errors++;
 197                                         if (status & 0x0002)
 198                                                 dev->stats.rx_crc_errors++;
 199                                         if (status & 0x0001)
 200                                                 dev->stats.rx_fifo_errors++;
 201                                }
 202                        } else {
 203                                struct sk_buff *skb;
 204
 205                                /* Check if the packet is long enough to accept without copying
 206                                   to a minimally-sized skbuff. */
 207                                if (pkt_len < tulip_rx_copybreak &&
 208                                    (skb = dev_alloc_skb(pkt_len + 2)) != NULL) {
 209                                        skb_reserve(skb, 2);    /* 16 byte align the IP header */
 210                                        pci_dma_sync_single_for_cpu(tp->pdev,
 211                                                                    tp->rx_buffers[entry].mapping,
 212                                                                    pkt_len, PCI_DMA_FROMDEVICE);
 213 #if ! defined(__alpha__)
 214                                        skb_copy_to_linear_data(skb, tp->rx_buffers[entry].skb->data,
 215                                                         pkt_len);
 216                                        skb_put(skb, pkt_len);
 217 #else
 218                                        memcpy(skb_put(skb, pkt_len),
 219                                               tp->rx_buffers[entry].skb->data,
 220                                               pkt_len);
 221 #endif
 222                                        pci_dma_sync_single_for_device(tp->pdev,
 223                                                                       tp->rx_buffers[entry].mapping,
 224                                                                       pkt_len, PCI_DMA_FROMDEVICE);
 225                                } else {        /* Pass up the skb already on the Rx ring. */
 226                                        char *temp = skb_put(skb = tp->rx_buffers[entry].skb,
 227                                                             pkt_len);
 228
 229 #ifndef final_version
 230                                        if (tp->rx_buffers[entry].mapping !=
 231                                            le32_to_cpu(tp->rx_ring[entry].buffer1)) {
 232                                                dev_err(&dev->dev,
 233                                                        "Internal fault: The skbuff addresses do not match in tulip_rx: %08x vs. %08llx %p / %p\n",
 234                                                        le32_to_cpu(tp->rx_ring[entry].buffer1),
 235                                                        (unsigned long long)tp->rx_buffers[entry].mapping,
 236                                                        skb->head, temp);
 237                                        }
 238 #endif
 239
 240                                        pci_unmap_single(tp->pdev, tp->rx_buffers[entry].mapping,
 241                                                         PKT_BUF_SZ, PCI_DMA_FROMDEVICE);
 242
 243                                        tp->rx_buffers[entry].skb = NULL;
 244                                        tp->rx_buffers[entry].mapping = 0;
 245                                }
 246                                skb->protocol = eth_type_trans(skb, dev);
 247
 248                                netif_receive_skb(skb);
 249
 250                                 dev->stats.rx_packets++;
 251                                 dev->stats.rx_bytes += pkt_len;
 252                        }
 253 #ifdef CONFIG_TULIP_NAPI_HW_MITIGATION
 254                        received++;
 255 #endif
 256
 257                        entry = (++tp->cur_rx) % RX_RING_SIZE;
 258                        if (tp->cur_rx - tp->dirty_rx > RX_RING_SIZE/4)
 259                                tulip_refill_rx(dev);
 260
 261                 }
 262
 263                /* New ack strategy... irq does not ack Rx any longer
 264                   hopefully this helps */
 265
 266                /* Really bad things can happen here... If new packet arrives
 267                 * and an irq arrives (tx or just due to occasionally unset
 268                 * mask), it will be acked by irq handler, but new thread
 269                 * is not scheduled. It is major hole in design.
 270                 * No idea how to fix this if "playing with fire" will fail
 271                 * tomorrow (night 011029). If it will not fail, we won
 272                 * finally: amount of IO did not increase at all. */
 273        } while ((ioread32(tp->base_addr + CSR5) & RxIntr));
 274
 275  #ifdef CONFIG_TULIP_NAPI_HW_MITIGATION
 276
 277           /* We use this simplistic scheme for IM. It's proven by
 278              real life installations. We can have IM enabled
 279             continuesly but this would cause unnecessary latency.
 280             Unfortunely we can't use all the NET_RX_* feedback here.
 281             This would turn on IM for devices that is not contributing
 282             to backlog congestion with unnecessary latency.
 283
 284              We monitor the device RX-ring and have:
 285
 286              HW Interrupt Mitigation either ON or OFF.
 287
 288             ON:  More then 1 pkt received (per intr.) OR we are dropping
 289              OFF: Only 1 pkt received
 290
 291              Note. We only use min and max (0, 15) settings from mit_table */
 292
 293
 294           if( tp->flags &  HAS_INTR_MITIGATION) {
 295                  if( received > 1 ) {
 296                          if( ! tp->mit_on ) {
 297                                  tp->mit_on = 1;
 298                                  iowrite32(mit_table[MIT_TABLE], tp->base_addr + CSR11);
 299                          }
 300                   }
 301                  else {
 302                          if( tp->mit_on ) {
 303                                  tp->mit_on = 0;
 304                                  iowrite32(0, tp->base_addr + CSR11);
 305                          }
 306                   }
 307           }
 308
 309 #endif /* CONFIG_TULIP_NAPI_HW_MITIGATION */
 310
 311          tulip_refill_rx(dev);
 312
 313          /* If RX ring is not full we are out of memory. */
 314          if (tp->rx_buffers[tp->dirty_rx % RX_RING_SIZE].skb == NULL)
 315                  goto oom;
 316
 317          /* Remove us from polling list and enable RX intr. */
 318
 319          napi_complete(napi);
 320          iowrite32(tulip_tbl[tp->chip_id].valid_intrs, tp->base_addr+CSR7);
 321
 322          /* The last op happens after poll completion. Which means the following:
 323           * 1. it can race with disabling irqs in irq handler
 324           * 2. it can race with dise/enabling irqs in other poll threads
 325           * 3. if an irq raised after beginning loop, it will be immediately
 326           *    triggered here.
 327           *
 328           * Summarizing: the logic results in some redundant irqs both
 329           * due to races in masking and due to too late acking of already
 330           * processed irqs. But it must not result in losing events.
 331           */
 332
 333          return work_done;
 334
 335  not_done:
 336          if (tp->cur_rx - tp->dirty_rx > RX_RING_SIZE/2 ||
 337              tp->rx_buffers[tp->dirty_rx % RX_RING_SIZE].skb == NULL)
 338                  tulip_refill_rx(dev);
 339
 340          if (tp->rx_buffers[tp->dirty_rx % RX_RING_SIZE].skb == NULL)
 341                  goto oom;
 342
 343          return work_done;
 344
 345  oom:    /* Executed with RX ints disabled */
 346
 347          /* Start timer, stop polling, but do not enable rx interrupts. */
 348          mod_timer(&tp->oom_timer, jiffies+1);
 349
 350          /* Think: timer_pending() was an explicit signature of bug.
 351           * Timer can be pending now but fired and completed
 352           * before we did napi_complete(). See? We would lose it. */
 353
 354          /* remove ourselves from the polling list */
 355          napi_complete(napi);
 356
 357          return work_done;
 358 }
 359
 360 #else /* CONFIG_TULIP_NAPI */
 361
 362 static int tulip_rx(struct net_device *dev)
 363 {
 364         struct tulip_private *tp = netdev_priv(dev);
 365         int entry = tp->cur_rx % RX_RING_SIZE;
 366         int rx_work_limit = tp->dirty_rx + RX_RING_SIZE - tp->cur_rx;
 367         int received = 0;
 368
 369         if (tulip_debug > 4)
 370                 netdev_dbg(dev, "In tulip_rx(), entry %d %08x\n",
 371                            entry, tp->rx_ring[entry].status);
 372         /* If we own the next entry, it is a new packet. Send it up. */
 373         while ( ! (tp->rx_ring[entry].status & cpu_to_le32(DescOwned))) {
 374                 s32 status = le32_to_cpu(tp->rx_ring[entry].status);
 375                 short pkt_len;
 376
 377                 if (tulip_debug > 5)
 378                         netdev_dbg(dev, "In tulip_rx(), entry %d %08x\n",
 379                                    entry, status);
 380                 if (--rx_work_limit < 0)
 381                         break;
 382
 383                 /*
 384                   Omit the four octet CRC from the length.
 385                   (May not be considered valid until we have
 386                   checked status for RxLengthOver2047 bits)
 387                 */
 388                 pkt_len = ((status >> 16) & 0x7ff) - 4;
 389                 /*
 390                   Maximum pkt_len is 1518 (1514 + vlan header)
 391                   Anything higher than this is always invalid
 392                   regardless of RxLengthOver2047 bits
 393                 */
 394
 395                 if ((status & (RxLengthOver2047 |
 396                                RxDescCRCError |
 397                                RxDescCollisionSeen |
 398                                RxDescRunt |
 399                                RxDescDescErr |
 400                                RxWholePkt))        != RxWholePkt ||
 401                     pkt_len > 1518) {
 402                         if ((status & (RxLengthOver2047 |
 403                              RxWholePkt))         != RxWholePkt) {
 404                                 /* Ingore earlier buffers. */
 405                                 if ((status & 0xffff) != 0x7fff) {
 406                                         if (tulip_debug > 1)
 407                                                 netdev_warn(dev,
 408                                                             "Oversized Ethernet frame spanned multiple buffers, status %08x!\n",
 409                                                             status);
 410                                         dev->stats.rx_length_errors++;
 411                                 }
 412                         } else {
 413                                 /* There was a fatal error. */
 414                                 if (tulip_debug > 2)
 415                                         netdev_dbg(dev, "Receive error, Rx status %08x\n",
 416                                                    status);
 417                                 dev->stats.rx_errors++; /* end of a packet.*/
 418                                 if (pkt_len > 1518 ||
 419                                     (status & RxDescRunt))
 420                                         dev->stats.rx_length_errors++;
 421                                 if (status & 0x0004)
 422                                         dev->stats.rx_frame_errors++;
 423                                 if (status & 0x0002)
 424                                         dev->stats.rx_crc_errors++;
 425                                 if (status & 0x0001)
 426                                         dev->stats.rx_fifo_errors++;
 427                         }
 428                 } else {
 429                         struct sk_buff *skb;
 430
 431                         /* Check if the packet is long enough to accept without copying
 432                            to a minimally-sized skbuff. */
 433                         if (pkt_len < tulip_rx_copybreak &&
 434                             (skb = dev_alloc_skb(pkt_len + 2)) != NULL) {
 435                                 skb_reserve(skb, 2);    /* 16 byte align the IP header */
 436                                 pci_dma_sync_single_for_cpu(tp->pdev,
 437                                                             tp->rx_buffers[entry].mapping,
 438                                                             pkt_len, PCI_DMA_FROMDEVICE);
 439 #if ! defined(__alpha__)
 440                                 skb_copy_to_linear_data(skb, tp->rx_buffers[entry].skb->data,
 441                                                  pkt_len);
 442                                 skb_put(skb, pkt_len);
 443 #else
 444                                 memcpy(skb_put(skb, pkt_len),
 445                                        tp->rx_buffers[entry].skb->data,
 446                                        pkt_len);
 447 #endif
 448                                 pci_dma_sync_single_for_device(tp->pdev,
 449                                                                tp->rx_buffers[entry].mapping,
 450                                                                pkt_len, PCI_DMA_FROMDEVICE);
 451                         } else {        /* Pass up the skb already on the Rx ring. */
 452                                 char *temp = skb_put(skb = tp->rx_buffers[entry].skb,
 453                                                      pkt_len);
 454
 455 #ifndef final_version
 456                                 if (tp->rx_buffers[entry].mapping !=
 457                                     le32_to_cpu(tp->rx_ring[entry].buffer1)) {
 458                                         dev_err(&dev->dev,
 459                                                 "Internal fault: The skbuff addresses do not match in tulip_rx: %08x vs. %Lx %p / %p\n",
 460                                                 le32_to_cpu(tp->rx_ring[entry].buffer1),
 461                                                 (long long)tp->rx_buffers[entry].mapping,
 462                                                 skb->head, temp);
 463                                 }
 464 #endif
 465
 466                                 pci_unmap_single(tp->pdev, tp->rx_buffers[entry].mapping,
 467                                                  PKT_BUF_SZ, PCI_DMA_FROMDEVICE);
 468
 469                                 tp->rx_buffers[entry].skb = NULL;
 470                                 tp->rx_buffers[entry].mapping = 0;
 471                         }
 472                         skb->protocol = eth_type_trans(skb, dev);
 473
 474                         netif_rx(skb);
 475
 476                         dev->stats.rx_packets++;
 477                         dev->stats.rx_bytes += pkt_len;
 478                 }
 479                 received++;
 480                 entry = (++tp->cur_rx) % RX_RING_SIZE;
 481         }
 482         return received;
 483 }
 484 #endif  /* CONFIG_TULIP_NAPI */
 485
 486 static inline unsigned int phy_interrupt (struct net_device *dev)
 487 {
 488 #ifdef __hppa__
 489         struct tulip_private *tp = netdev_priv(dev);
 490         int csr12 = ioread32(tp->base_addr + CSR12) & 0xff;
 491
 492         if (csr12 != tp->csr12_shadow) {
 493                 /* ack interrupt */
 494                 iowrite32(csr12 | 0x02, tp->base_addr + CSR12);
 495                 tp->csr12_shadow = csr12;
 496                 /* do link change stuff */
 497                 spin_lock(&tp->lock);
 498                 tulip_check_duplex(dev);
 499                 spin_unlock(&tp->lock);
 500                 /* clear irq ack bit */
 501                 iowrite32(csr12 & ~0x02, tp->base_addr + CSR12);
 502
 503                 return 1;
 504         }
 505 #endif
 506
 507         return 0;
 508 }
 509
 510 /* The interrupt handler does all of the Rx thread work and cleans up
 511    after the Tx thread. */
 512 irqreturn_t tulip_interrupt(int irq, void *dev_instance)
 513 {
 514         struct net_device *dev = (struct net_device *)dev_instance;
 515         struct tulip_private *tp = netdev_priv(dev);
 516         void __iomem *ioaddr = tp->base_addr;
 517         int csr5;
 518         int missed;
 519         int rx = 0;
 520         int tx = 0;
 521         int oi = 0;
 522         int maxrx = RX_RING_SIZE;
 523         int maxtx = TX_RING_SIZE;
 524         int maxoi = TX_RING_SIZE;
 525 #ifdef CONFIG_TULIP_NAPI
 526         int rxd = 0;
 527 #else
 528         int entry;
 529 #endif
 530         unsigned int work_count = tulip_max_interrupt_work;
 531         unsigned int handled = 0;
 532
 533         /* Let's see whether the interrupt really is for us */
 534         csr5 = ioread32(ioaddr + CSR5);
 535
 536         if (tp->flags & HAS_PHY_IRQ)
 537                 handled = phy_interrupt (dev);
 538
 539         if ((csr5 & (NormalIntr|AbnormalIntr)) == 0)
 540                 return IRQ_RETVAL(handled);
 541
 542         tp->nir++;
 543
 544         do {
 545
 546 #ifdef CONFIG_TULIP_NAPI
 547
 548                 if (!rxd && (csr5 & (RxIntr | RxNoBuf))) {
 549                         rxd++;
 550                         /* Mask RX intrs and add the device to poll list. */
 551                         iowrite32(tulip_tbl[tp->chip_id].valid_intrs&~RxPollInt, ioaddr + CSR7);
 552                         napi_schedule(&tp->napi);
 553
 554                         if (!(csr5&~(AbnormalIntr|NormalIntr|RxPollInt|TPLnkPass)))
 555                                break;
 556                 }
 557
 558                /* Acknowledge the interrupt sources we handle here ASAP
 559                   the poll function does Rx and RxNoBuf acking */
 560
 561                 iowrite32(csr5 & 0x0001ff3f, ioaddr + CSR5);
 562
 563 #else
 564                 /* Acknowledge all of the current interrupt sources ASAP. */
 565                 iowrite32(csr5 & 0x0001ffff, ioaddr + CSR5);
 566
 567
 568                 if (csr5 & (RxIntr | RxNoBuf)) {
 569                                 rx += tulip_rx(dev);
 570                         tulip_refill_rx(dev);
 571                 }
 572
 573 #endif /*  CONFIG_TULIP_NAPI */
 574
 575                 if (tulip_debug > 4)
 576                         netdev_dbg(dev, "interrupt  csr5=%#8.8x new csr5=%#8.8x\n",
 577                                    csr5, ioread32(ioaddr + CSR5));
 578
 579
 580                 if (csr5 & (TxNoBuf | TxDied | TxIntr | TimerInt)) {
 581                         unsigned int dirty_tx;
 582
 583                         spin_lock(&tp->lock);
 584
 585                         for (dirty_tx = tp->dirty_tx; tp->cur_tx - dirty_tx > 0;
 586                                  dirty_tx++) {
 587                                 int entry = dirty_tx % TX_RING_SIZE;
 588                                 int status = le32_to_cpu(tp->tx_ring[entry].status);
 589
 590                                 if (status < 0)
 591                                         break;                  /* It still has not been Txed */
 592
 593                                 /* Check for Rx filter setup frames. */
 594                                 if (tp->tx_buffers[entry].skb == NULL) {
 595                                         /* test because dummy frames not mapped */
 596                                         if (tp->tx_buffers[entry].mapping)
 597                                                 pci_unmap_single(tp->pdev,
 598                                                          tp->tx_buffers[entry].mapping,
 599                                                          sizeof(tp->setup_frame),
 600                                                          PCI_DMA_TODEVICE);
 601                                         continue;
 602                                 }
 603
 604                                 if (status & 0x8000) {
 605                                         /* There was an major error, log it. */
 606 #ifndef final_version
 607                                         if (tulip_debug > 1)
 608                                                 netdev_dbg(dev, "Transmit error, Tx status %08x\n",
 609                                                            status);
 610 #endif
 611                                         dev->stats.tx_errors++;
 612                                         if (status & 0x4104)
 613                                                 dev->stats.tx_aborted_errors++;
 614                                         if (status & 0x0C00)
 615                                                 dev->stats.tx_carrier_errors++;
 616                                         if (status & 0x0200)
 617                                                 dev->stats.tx_window_errors++;
 618                                         if (status & 0x0002)
 619                                                 dev->stats.tx_fifo_errors++;
 620                                         if ((status & 0x0080) && tp->full_duplex == 0)
 621                                                 dev->stats.tx_heartbeat_errors++;
 622                                 } else {
 623                                         dev->stats.tx_bytes +=
 624                                                 tp->tx_buffers[entry].skb->len;
 625                                         dev->stats.collisions += (status >> 3) & 15;
 626                                         dev->stats.tx_packets++;
 627                                 }
 628
 629                                 pci_unmap_single(tp->pdev, tp->tx_buffers[entry].mapping,
 630                                                  tp->tx_buffers[entry].skb->len,
 631                                                  PCI_DMA_TODEVICE);
 632
 633                                 /* Free the original skb. */
 634                                 dev_kfree_skb_irq(tp->tx_buffers[entry].skb);
 635                                 tp->tx_buffers[entry].skb = NULL;
 636                                 tp->tx_buffers[entry].mapping = 0;
 637                                 tx++;
 638                         }
 639
 640 #ifndef final_version
 641                         if (tp->cur_tx - dirty_tx > TX_RING_SIZE) {
 642                                 dev_err(&dev->dev,
 643                                         "Out-of-sync dirty pointer, %d vs. %d\n",
 644                                         dirty_tx, tp->cur_tx);
 645                                 dirty_tx += TX_RING_SIZE;
 646                         }
 647 #endif
 648
 649                         if (tp->cur_tx - dirty_tx < TX_RING_SIZE - 2)
 650                                 netif_wake_queue(dev);
 651
 652                         tp->dirty_tx = dirty_tx;
 653                         if (csr5 & TxDied) {
 654                                 if (tulip_debug > 2)
 655                                         dev_warn(&dev->dev,
 656                                                  "The transmitter stopped.  CSR5 is %x, CSR6 %x, new CSR6 %x\n",
 657                                                  csr5, ioread32(ioaddr + CSR6),
 658                                                  tp->csr6);
 659                                 tulip_restart_rxtx(tp);
 660                         }
 661                         spin_unlock(&tp->lock);
 662                 }
 663
 664                 /* Log errors. */
 665                 if (csr5 & AbnormalIntr) {      /* Abnormal error summary bit. */
 666                         if (csr5 == 0xffffffff)
 667                                 break;
 668                         if (csr5 & TxJabber)
 669                                 dev->stats.tx_errors++;
 670                         if (csr5 & TxFIFOUnderflow) {
 671                                 if ((tp->csr6 & 0xC000) != 0xC000)
 672                                         tp->csr6 += 0x4000;     /* Bump up the Tx threshold */
 673                                 else
 674                                         tp->csr6 |= 0x00200000;  /* Store-n-forward. */
 675                                 /* Restart the transmit process. */
 676                                 tulip_restart_rxtx(tp);
 677                                 iowrite32(0, ioaddr + CSR1);
 678                         }
 679                         if (csr5 & (RxDied | RxNoBuf)) {
 680                                 if (tp->flags & COMET_MAC_ADDR) {
 681                                         iowrite32(tp->mc_filter[0], ioaddr + 0xAC);
 682                                         iowrite32(tp->mc_filter[1], ioaddr + 0xB0);
 683                                 }
 684                         }
 685                         if (csr5 & RxDied) {            /* Missed a Rx frame. */
 686                                 dev->stats.rx_missed_errors += ioread32(ioaddr + CSR8) & 0xffff;
 687                                 dev->stats.rx_errors++;
 688                                 tulip_start_rxtx(tp);
 689                         }
 690                         /*
 691                          * NB: t21142_lnk_change() does a del_timer_sync(), so be careful if this
 692                          * call is ever done under the spinlock
 693                          */
 694                         if (csr5 & (TPLnkPass | TPLnkFail | 0x08000000)) {
 695                                 if (tp->link_change)
 696                                         (tp->link_change)(dev, csr5);
 697                         }
 698                         if (csr5 & SystemError) {
 699                                 int error = (csr5 >> 23) & 7;
 700                                 /* oops, we hit a PCI error.  The code produced corresponds
 701                                  * to the reason:
 702                                  *  0 - parity error
 703                                  *  1 - master abort
 704                                  *  2 - target abort
 705                                  * Note that on parity error, we should do a software reset
 706                                  * of the chip to get it back into a sane state (according
 707                                  * to the 21142/3 docs that is).
 708                                  *   -- rmk
 709                                  */
 710                                 dev_err(&dev->dev,
 711                                         "(%lu) System Error occurred (%d)\n",
 712                                         tp->nir, error);
 713                         }
 714                         /* Clear all error sources, included undocumented ones! */
 715                         iowrite32(0x0800f7ba, ioaddr + CSR5);
 716                         oi++;
 717                 }
 718                 if (csr5 & TimerInt) {
 719
 720                         if (tulip_debug > 2)
 721                                 dev_err(&dev->dev,
 722                                         "Re-enabling interrupts, %08x\n",
 723                                         csr5);
 724                         iowrite32(tulip_tbl[tp->chip_id].valid_intrs, ioaddr + CSR7);
 725                         tp->ttimer = 0;
 726                         oi++;
 727                 }
 728                 if (tx > maxtx || rx > maxrx || oi > maxoi) {
 729                         if (tulip_debug > 1)
 730                                 dev_warn(&dev->dev, "Too much work during an interrupt, csr5=0x%08x. (%lu) (%d,%d,%d)\n",
 731                                          csr5, tp->nir, tx, rx, oi);
 732
 733                        /* Acknowledge all interrupt sources. */
 734                         iowrite32(0x8001ffff, ioaddr + CSR5);
 735                         if (tp->flags & HAS_INTR_MITIGATION) {
 736                      /* Josip Loncaric at ICASE did extensive experimentation
 737                         to develop a good interrupt mitigation setting.*/
 738                                 iowrite32(0x8b240000, ioaddr + CSR11);
 739                         } else if (tp->chip_id == LC82C168) {
 740                                 /* the LC82C168 doesn't have a hw timer.*/
 741                                 iowrite32(0x00, ioaddr + CSR7);
 742                                 mod_timer(&tp->timer, RUN_AT(HZ/50));
 743                         } else {
 744                           /* Mask all interrupting sources, set timer to
 745                                 re-enable. */
 746                                 iowrite32(((~csr5) & 0x0001ebef) | AbnormalIntr | TimerInt, ioaddr + CSR7);
 747                                 iowrite32(0x0012, ioaddr + CSR11);
 748                         }
 749                         break;
 750                 }
 751
 752                 work_count--;
 753                 if (work_count == 0)
 754                         break;
 755
 756                 csr5 = ioread32(ioaddr + CSR5);
 757
 758 #ifdef CONFIG_TULIP_NAPI
 759                 if (rxd)
 760                         csr5 &= ~RxPollInt;
 761         } while ((csr5 & (TxNoBuf |
 762                           TxDied |
 763                           TxIntr |
 764                           TimerInt |
 765                           /* Abnormal intr. */
 766                           RxDied |
 767                           TxFIFOUnderflow |
 768                           TxJabber |
 769                           TPLnkFail |
 770                           SystemError )) != 0);
 771 #else
 772         } while ((csr5 & (NormalIntr|AbnormalIntr)) != 0);
 773
 774         tulip_refill_rx(dev);
 775
 776         /* check if the card is in suspend mode */
 777         entry = tp->dirty_rx % RX_RING_SIZE;
 778         if (tp->rx_buffers[entry].skb == NULL) {
 779                 if (tulip_debug > 1)
 780                         dev_warn(&dev->dev,
 781                                  "in rx suspend mode: (%lu) (tp->cur_rx = %u, ttimer = %d, rx = %d) go/stay in suspend mode\n",
 782                                  tp->nir, tp->cur_rx, tp->ttimer, rx);
 783                 if (tp->chip_id == LC82C168) {
 784                         iowrite32(0x00, ioaddr + CSR7);
 785                         mod_timer(&tp->timer, RUN_AT(HZ/50));
 786                 } else {
 787                         if (tp->ttimer == 0 || (ioread32(ioaddr + CSR11) & 0xffff) == 0) {
 788                                 if (tulip_debug > 1)
 789                                         dev_warn(&dev->dev,
 790                                                  "in rx suspend mode: (%lu) set timer\n",
 791                                                  tp->nir);
 792                                 iowrite32(tulip_tbl[tp->chip_id].valid_intrs | TimerInt,
 793                                         ioaddr + CSR7);
 794                                 iowrite32(TimerInt, ioaddr + CSR5);
 795                                 iowrite32(12, ioaddr + CSR11);
 796                                 tp->ttimer = 1;
 797                         }
 798                 }
 799         }
 800 #endif /* CONFIG_TULIP_NAPI */
 801
 802         if ((missed = ioread32(ioaddr + CSR8) & 0x1ffff)) {
 803                 dev->stats.rx_dropped += missed & 0x10000 ? 0x10000 : missed;
 804         }
 805
 806         if (tulip_debug > 4)
 807                 netdev_dbg(dev, "exiting interrupt, csr5=%#04x\n",
 808                            ioread32(ioaddr + CSR5));
 809
 810         return IRQ_HANDLED;
 811 }