drivers/net/sgiseeq.c

   1 /*
   2  * sgiseeq.c: Seeq8003 ethernet driver for SGI machines.
   3  *
   4  * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
   5  */
   6
   7 #undef DEBUG
   8
   9 #include <linux/kernel.h>
  10 #include <linux/module.h>
  11 #include <linux/slab.h>
  12 #include <linux/errno.h>
  13 #include <linux/init.h>
  14 #include <linux/types.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/string.h>
  17 #include <linux/delay.h>
  18 #include <linux/netdevice.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/etherdevice.h>
  21 #include <linux/skbuff.h>
  22
  23 #include <asm/sgi/hpc3.h>
  24 #include <asm/sgi/ip22.h>
  25 #include <asm/sgi/seeq.h>
  26
  27 #include "sgiseeq.h"
  28
  29 static char *sgiseeqstr = "SGI Seeq8003";
  30
  31 /*
  32  * If you want speed, you do something silly, it always has worked for me.  So,
  33  * with that in mind, I've decided to make this driver look completely like a
  34  * stupid Lance from a driver architecture perspective.  Only difference is that
  35  * here our "ring buffer" looks and acts like a real Lance one does but is
  36  * laid out like how the HPC DMA and the Seeq want it to.  You'd be surprised
  37  * how a stupid idea like this can pay off in performance, not to mention
  38  * making this driver 2,000 times easier to write. ;-)
  39  */
  40
  41 /* Tune these if we tend to run out often etc. */
  42 #define SEEQ_RX_BUFFERS  16
  43 #define SEEQ_TX_BUFFERS  16
  44
  45 #define PKT_BUF_SZ       1584
  46
  47 #define NEXT_RX(i)  (((i) + 1) & (SEEQ_RX_BUFFERS - 1))
  48 #define NEXT_TX(i)  (((i) + 1) & (SEEQ_TX_BUFFERS - 1))
  49 #define PREV_RX(i)  (((i) - 1) & (SEEQ_RX_BUFFERS - 1))
  50 #define PREV_TX(i)  (((i) - 1) & (SEEQ_TX_BUFFERS - 1))
  51
  52 #define TX_BUFFS_AVAIL(sp) ((sp->tx_old <= sp->tx_new) ? \
  53                             sp->tx_old + (SEEQ_TX_BUFFERS - 1) - sp->tx_new : \
  54                             sp->tx_old - sp->tx_new - 1)
  55
  56 #define VIRT_TO_DMA(sp, v) ((sp)->srings_dma +                                 \
  57                                   (dma_addr_t)((unsigned long)(v) -            \
  58                                                (unsigned long)((sp)->rx_desc)))
  59
  60 /* Copy frames shorter than rx_copybreak, otherwise pass on up in
  61  * a full sized sk_buff.  Value of 100 stolen from tulip.c (!alpha).
  62  */
  63 static int rx_copybreak = 100;
  64
  65 #define PAD_SIZE    (128 - sizeof(struct hpc_dma_desc) - sizeof(void *))
  66
  67 struct sgiseeq_rx_desc {
  68         volatile struct hpc_dma_desc rdma;
  69         u8 padding[PAD_SIZE];
  70         struct sk_buff *skb;
  71 };
  72
  73 struct sgiseeq_tx_desc {
  74         volatile struct hpc_dma_desc tdma;
  75         u8 padding[PAD_SIZE];
  76         struct sk_buff *skb;
  77 };
  78
  79 /*
  80  * Warning: This structure is laid out in a certain way because HPC dma
  81  *          descriptors must be 8-byte aligned.  So don't touch this without
  82  *          some care.
  83  */
  84 struct sgiseeq_init_block { /* Note the name ;-) */
  85         struct sgiseeq_rx_desc rxvector[SEEQ_RX_BUFFERS];
  86         struct sgiseeq_tx_desc txvector[SEEQ_TX_BUFFERS];
  87 };
  88
  89 struct sgiseeq_private {
  90         struct sgiseeq_init_block *srings;
  91         dma_addr_t srings_dma;
  92
  93         /* Ptrs to the descriptors in uncached space. */
  94         struct sgiseeq_rx_desc *rx_desc;
  95         struct sgiseeq_tx_desc *tx_desc;
  96
  97         char *name;
  98         struct hpc3_ethregs *hregs;
  99         struct sgiseeq_regs *sregs;
 100
 101         /* Ring entry counters. */
 102         unsigned int rx_new, tx_new;
 103         unsigned int rx_old, tx_old;
 104
 105         int is_edlc;
 106         unsigned char control;
 107         unsigned char mode;
 108
 109         spinlock_t tx_lock;
 110 };
 111
 112 static inline void dma_sync_desc_cpu(struct net_device *dev, void *addr)
 113 {
 114         dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc),
 115                        DMA_FROM_DEVICE);
 116 }
 117
 118 static inline void dma_sync_desc_dev(struct net_device *dev, void *addr)
 119 {
 120         dma_cache_sync(dev->dev.parent, addr, sizeof(struct sgiseeq_rx_desc),
 121                        DMA_TO_DEVICE);
 122 }
 123
 124 static inline void hpc3_eth_reset(struct hpc3_ethregs *hregs)
 125 {
 126         hregs->reset = HPC3_ERST_CRESET | HPC3_ERST_CLRIRQ;
 127         udelay(20);
 128         hregs->reset = 0;
 129 }
 130
 131 static inline void reset_hpc3_and_seeq(struct hpc3_ethregs *hregs,
 132                                        struct sgiseeq_regs *sregs)
 133 {
 134         hregs->rx_ctrl = hregs->tx_ctrl = 0;
 135         hpc3_eth_reset(hregs);
 136 }
 137
 138 #define RSTAT_GO_BITS (SEEQ_RCMD_IGOOD | SEEQ_RCMD_IEOF | SEEQ_RCMD_ISHORT | \
 139                        SEEQ_RCMD_IDRIB | SEEQ_RCMD_ICRC)
 140
 141 static inline void seeq_go(struct sgiseeq_private *sp,
 142                            struct hpc3_ethregs *hregs,
 143                            struct sgiseeq_regs *sregs)
 144 {
 145         sregs->rstat = sp->mode | RSTAT_GO_BITS;
 146         hregs->rx_ctrl = HPC3_ERXCTRL_ACTIVE;
 147 }
 148
 149 static inline void __sgiseeq_set_mac_address(struct net_device *dev)
 150 {
 151         struct sgiseeq_private *sp = netdev_priv(dev);
 152         struct sgiseeq_regs *sregs = sp->sregs;
 153         int i;
 154
 155         sregs->tstat = SEEQ_TCMD_RB0;
 156         for (i = 0; i < 6; i++)
 157                 sregs->rw.eth_addr[i] = dev->dev_addr[i];
 158 }
 159
 160 static int sgiseeq_set_mac_address(struct net_device *dev, void *addr)
 161 {
 162         struct sgiseeq_private *sp = netdev_priv(dev);
 163         struct sockaddr *sa = addr;
 164
 165         memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
 166
 167         spin_lock_irq(&sp->tx_lock);
 168         __sgiseeq_set_mac_address(dev);
 169         spin_unlock_irq(&sp->tx_lock);
 170
 171         return 0;
 172 }
 173
 174 #define TCNTINFO_INIT (HPCDMA_EOX | HPCDMA_ETXD)
 175 #define RCNTCFG_INIT  (HPCDMA_OWN | HPCDMA_EORP | HPCDMA_XIE)
 176 #define RCNTINFO_INIT (RCNTCFG_INIT | (PKT_BUF_SZ & HPCDMA_BCNT))
 177
 178 static int seeq_init_ring(struct net_device *dev)
 179 {
 180         struct sgiseeq_private *sp = netdev_priv(dev);
 181         int i;
 182
 183         netif_stop_queue(dev);
 184         sp->rx_new = sp->tx_new = 0;
 185         sp->rx_old = sp->tx_old = 0;
 186
 187         __sgiseeq_set_mac_address(dev);
 188
 189         /* Setup tx ring. */
 190         for(i = 0; i < SEEQ_TX_BUFFERS; i++) {
 191                 sp->tx_desc[i].tdma.cntinfo = TCNTINFO_INIT;
 192                 dma_sync_desc_dev(dev, &sp->tx_desc[i]);
 193         }
 194
 195         /* And now the rx ring. */
 196         for (i = 0; i < SEEQ_RX_BUFFERS; i++) {
 197                 if (!sp->rx_desc[i].skb) {
 198                         dma_addr_t dma_addr;
 199                         struct sk_buff *skb = netdev_alloc_skb(dev, PKT_BUF_SZ);
 200
 201                         if (skb == NULL)
 202                                 return -ENOMEM;
 203                         skb_reserve(skb, 2);
 204                         dma_addr = dma_map_single(dev->dev.parent,
 205                                                   skb->data - 2,
 206                                                   PKT_BUF_SZ, DMA_FROM_DEVICE);
 207                         sp->rx_desc[i].skb = skb;
 208                         sp->rx_desc[i].rdma.pbuf = dma_addr;
 209                 }
 210                 sp->rx_desc[i].rdma.cntinfo = RCNTINFO_INIT;
 211                 dma_sync_desc_dev(dev, &sp->rx_desc[i]);
 212         }
 213         sp->rx_desc[i - 1].rdma.cntinfo |= HPCDMA_EOR;
 214         dma_sync_desc_dev(dev, &sp->rx_desc[i - 1]);
 215         return 0;
 216 }
 217
 218 static void seeq_purge_ring(struct net_device *dev)
 219 {
 220         struct sgiseeq_private *sp = netdev_priv(dev);
 221         int i;
 222
 223         /* clear tx ring. */
 224         for (i = 0; i < SEEQ_TX_BUFFERS; i++) {
 225                 if (sp->tx_desc[i].skb) {
 226                         dev_kfree_skb(sp->tx_desc[i].skb);
 227                         sp->tx_desc[i].skb = NULL;
 228                 }
 229         }
 230
 231         /* And now the rx ring. */
 232         for (i = 0; i < SEEQ_RX_BUFFERS; i++) {
 233                 if (sp->rx_desc[i].skb) {
 234                         dev_kfree_skb(sp->rx_desc[i].skb);
 235                         sp->rx_desc[i].skb = NULL;
 236                 }
 237         }
 238 }
 239
 240 #ifdef DEBUG
 241 static struct sgiseeq_private *gpriv;
 242 static struct net_device *gdev;
 243
 244 static void sgiseeq_dump_rings(void)
 245 {
 246         static int once;
 247         struct sgiseeq_rx_desc *r = gpriv->rx_desc;
 248         struct sgiseeq_tx_desc *t = gpriv->tx_desc;
 249         struct hpc3_ethregs *hregs = gpriv->hregs;
 250         int i;
 251
 252         if (once)
 253                 return;
 254         once++;
 255         printk("RING DUMP:\n");
 256         for (i = 0; i < SEEQ_RX_BUFFERS; i++) {
 257                 printk("RX [%d]: @(%p) [%08x,%08x,%08x] ",
 258                        i, (&r[i]), r[i].rdma.pbuf, r[i].rdma.cntinfo,
 259                        r[i].rdma.pnext);
 260                 i += 1;
 261                 printk("-- [%d]: @(%p) [%08x,%08x,%08x]\n",
 262                        i, (&r[i]), r[i].rdma.pbuf, r[i].rdma.cntinfo,
 263                        r[i].rdma.pnext);
 264         }
 265         for (i = 0; i < SEEQ_TX_BUFFERS; i++) {
 266                 printk("TX [%d]: @(%p) [%08x,%08x,%08x] ",
 267                        i, (&t[i]), t[i].tdma.pbuf, t[i].tdma.cntinfo,
 268                        t[i].tdma.pnext);
 269                 i += 1;
 270                 printk("-- [%d]: @(%p) [%08x,%08x,%08x]\n",
 271                        i, (&t[i]), t[i].tdma.pbuf, t[i].tdma.cntinfo,
 272                        t[i].tdma.pnext);
 273         }
 274         printk("INFO: [rx_new = %d rx_old=%d] [tx_new = %d tx_old = %d]\n",
 275                gpriv->rx_new, gpriv->rx_old, gpriv->tx_new, gpriv->tx_old);
 276         printk("RREGS: rx_cbptr[%08x] rx_ndptr[%08x] rx_ctrl[%08x]\n",
 277                hregs->rx_cbptr, hregs->rx_ndptr, hregs->rx_ctrl);
 278         printk("TREGS: tx_cbptr[%08x] tx_ndptr[%08x] tx_ctrl[%08x]\n",
 279                hregs->tx_cbptr, hregs->tx_ndptr, hregs->tx_ctrl);
 280 }
 281 #endif
 282
 283 #define TSTAT_INIT_SEEQ (SEEQ_TCMD_IPT|SEEQ_TCMD_I16|SEEQ_TCMD_IC|SEEQ_TCMD_IUF)
 284 #define TSTAT_INIT_EDLC ((TSTAT_INIT_SEEQ) | SEEQ_TCMD_RB2)
 285
 286 static int init_seeq(struct net_device *dev, struct sgiseeq_private *sp,
 287                      struct sgiseeq_regs *sregs)
 288 {
 289         struct hpc3_ethregs *hregs = sp->hregs;
 290         int err;
 291
 292         reset_hpc3_and_seeq(hregs, sregs);
 293         err = seeq_init_ring(dev);
 294         if (err)
 295                 return err;
 296
 297         /* Setup to field the proper interrupt types. */
 298         if (sp->is_edlc) {
 299                 sregs->tstat = TSTAT_INIT_EDLC;
 300                 sregs->rw.wregs.control = sp->control;
 301                 sregs->rw.wregs.frame_gap = 0;
 302         } else {
 303                 sregs->tstat = TSTAT_INIT_SEEQ;
 304         }
 305
 306         hregs->rx_ndptr = VIRT_TO_DMA(sp, sp->rx_desc);
 307         hregs->tx_ndptr = VIRT_TO_DMA(sp, sp->tx_desc);
 308
 309         seeq_go(sp, hregs, sregs);
 310         return 0;
 311 }
 312
 313 static void record_rx_errors(struct net_device *dev, unsigned char status)
 314 {
 315         if (status & SEEQ_RSTAT_OVERF ||
 316             status & SEEQ_RSTAT_SFRAME)
 317                 dev->stats.rx_over_errors++;
 318         if (status & SEEQ_RSTAT_CERROR)
 319                 dev->stats.rx_crc_errors++;
 320         if (status & SEEQ_RSTAT_DERROR)
 321                 dev->stats.rx_frame_errors++;
 322         if (status & SEEQ_RSTAT_REOF)
 323                 dev->stats.rx_errors++;
 324 }
 325
 326 static inline void rx_maybe_restart(struct sgiseeq_private *sp,
 327                                     struct hpc3_ethregs *hregs,
 328                                     struct sgiseeq_regs *sregs)
 329 {
 330         if (!(hregs->rx_ctrl & HPC3_ERXCTRL_ACTIVE)) {
 331                 hregs->rx_ndptr = VIRT_TO_DMA(sp, sp->rx_desc + sp->rx_new);
 332                 seeq_go(sp, hregs, sregs);
 333         }
 334 }
 335
 336 static inline void sgiseeq_rx(struct net_device *dev, struct sgiseeq_private *sp,
 337                               struct hpc3_ethregs *hregs,
 338                               struct sgiseeq_regs *sregs)
 339 {
 340         struct sgiseeq_rx_desc *rd;
 341         struct sk_buff *skb = NULL;
 342         struct sk_buff *newskb;
 343         unsigned char pkt_status;
 344         int len = 0;
 345         unsigned int orig_end = PREV_RX(sp->rx_new);
 346
 347         /* Service every received packet. */
 348         rd = &sp->rx_desc[sp->rx_new];
 349         dma_sync_desc_cpu(dev, rd);
 350         while (!(rd->rdma.cntinfo & HPCDMA_OWN)) {
 351                 len = PKT_BUF_SZ - (rd->rdma.cntinfo & HPCDMA_BCNT) - 3;
 352                 dma_unmap_single(dev->dev.parent, rd->rdma.pbuf,
 353                                  PKT_BUF_SZ, DMA_FROM_DEVICE);
 354                 pkt_status = rd->skb->data[len];
 355                 if (pkt_status & SEEQ_RSTAT_FIG) {
 356                         /* Packet is OK. */
 357                         /* We don't want to receive our own packets */
 358                         if (memcmp(rd->skb->data + 6, dev->dev_addr, ETH_ALEN)) {
 359                                 if (len > rx_copybreak) {
 360                                         skb = rd->skb;
 361                                         newskb = netdev_alloc_skb(dev, PKT_BUF_SZ);
 362                                         if (!newskb) {
 363                                                 newskb = skb;
 364                                                 skb = NULL;
 365                                                 goto memory_squeeze;
 366                                         }
 367                                         skb_reserve(newskb, 2);
 368                                 } else {
 369                                         skb = netdev_alloc_skb_ip_align(dev, len);
 370                                         if (skb)
 371                                                 skb_copy_to_linear_data(skb, rd->skb->data, len);
 372
 373                                         newskb = rd->skb;
 374                                 }
 375 memory_squeeze:
 376                                 if (skb) {
 377                                         skb_put(skb, len);
 378                                         skb->protocol = eth_type_trans(skb, dev);
 379                                         netif_rx(skb);
 380                                         dev->stats.rx_packets++;
 381                                         dev->stats.rx_bytes += len;
 382                                 } else {
 383                                         printk(KERN_NOTICE "%s: Memory squeeze, deferring packet.\n",
 384                                                 dev->name);
 385                                         dev->stats.rx_dropped++;
 386                                 }
 387                         } else {
 388                                 /* Silently drop my own packets */
 389                                 newskb = rd->skb;
 390                         }
 391                 } else {
 392                         record_rx_errors(dev, pkt_status);
 393                         newskb = rd->skb;
 394                 }
 395                 rd->skb = newskb;
 396                 rd->rdma.pbuf = dma_map_single(dev->dev.parent,
 397                                                newskb->data - 2,
 398                                                PKT_BUF_SZ, DMA_FROM_DEVICE);
 399
 400                 /* Return the entry to the ring pool. */
 401                 rd->rdma.cntinfo = RCNTINFO_INIT;
 402                 sp->rx_new = NEXT_RX(sp->rx_new);
 403                 dma_sync_desc_dev(dev, rd);
 404                 rd = &sp->rx_desc[sp->rx_new];
 405                 dma_sync_desc_cpu(dev, rd);
 406         }
 407         dma_sync_desc_cpu(dev, &sp->rx_desc[orig_end]);
 408         sp->rx_desc[orig_end].rdma.cntinfo &= ~(HPCDMA_EOR);
 409         dma_sync_desc_dev(dev, &sp->rx_desc[orig_end]);
 410         dma_sync_desc_cpu(dev, &sp->rx_desc[PREV_RX(sp->rx_new)]);
 411         sp->rx_desc[PREV_RX(sp->rx_new)].rdma.cntinfo |= HPCDMA_EOR;
 412         dma_sync_desc_dev(dev, &sp->rx_desc[PREV_RX(sp->rx_new)]);
 413         rx_maybe_restart(sp, hregs, sregs);
 414 }
 415
 416 static inline void tx_maybe_reset_collisions(struct sgiseeq_private *sp,
 417                                              struct sgiseeq_regs *sregs)
 418 {
 419         if (sp->is_edlc) {
 420                 sregs->rw.wregs.control = sp->control & ~(SEEQ_CTRL_XCNT);
 421                 sregs->rw.wregs.control = sp->control;
 422         }
 423 }
 424
 425 static inline void kick_tx(struct net_device *dev,
 426                            struct sgiseeq_private *sp,
 427                            struct hpc3_ethregs *hregs)
 428 {
 429         struct sgiseeq_tx_desc *td;
 430         int i = sp->tx_old;
 431
 432         /* If the HPC aint doin nothin, and there are more packets
 433          * with ETXD cleared and XIU set we must make very certain
 434          * that we restart the HPC else we risk locking up the
 435          * adapter.  The following code is only safe iff the HPCDMA
 436          * is not active!
 437          */
 438         td = &sp->tx_desc[i];
 439         dma_sync_desc_cpu(dev, td);
 440         while ((td->tdma.cntinfo & (HPCDMA_XIU | HPCDMA_ETXD)) ==
 441               (HPCDMA_XIU | HPCDMA_ETXD)) {
 442                 i = NEXT_TX(i);
 443                 td = &sp->tx_desc[i];
 444                 dma_sync_desc_cpu(dev, td);
 445         }
 446         if (td->tdma.cntinfo & HPCDMA_XIU) {
 447                 hregs->tx_ndptr = VIRT_TO_DMA(sp, td);
 448                 hregs->tx_ctrl = HPC3_ETXCTRL_ACTIVE;
 449         }
 450 }
 451
 452 static inline void sgiseeq_tx(struct net_device *dev, struct sgiseeq_private *sp,
 453                               struct hpc3_ethregs *hregs,
 454                               struct sgiseeq_regs *sregs)
 455 {
 456         struct sgiseeq_tx_desc *td;
 457         unsigned long status = hregs->tx_ctrl;
 458         int j;
 459
 460         tx_maybe_reset_collisions(sp, sregs);
 461
 462         if (!(status & (HPC3_ETXCTRL_ACTIVE | SEEQ_TSTAT_PTRANS))) {
 463                 /* Oops, HPC detected some sort of error. */
 464                 if (status & SEEQ_TSTAT_R16)
 465                         dev->stats.tx_aborted_errors++;
 466                 if (status & SEEQ_TSTAT_UFLOW)
 467                         dev->stats.tx_fifo_errors++;
 468                 if (status & SEEQ_TSTAT_LCLS)
 469                         dev->stats.collisions++;
 470         }
 471
 472         /* Ack 'em... */
 473         for (j = sp->tx_old; j != sp->tx_new; j = NEXT_TX(j)) {
 474                 td = &sp->tx_desc[j];
 475
 476                 dma_sync_desc_cpu(dev, td);
 477                 if (!(td->tdma.cntinfo & (HPCDMA_XIU)))
 478                         break;
 479                 if (!(td->tdma.cntinfo & (HPCDMA_ETXD))) {
 480                         if (!(status & HPC3_ETXCTRL_ACTIVE)) {
 481                                 hregs->tx_ndptr = VIRT_TO_DMA(sp, td);
 482                                 hregs->tx_ctrl = HPC3_ETXCTRL_ACTIVE;
 483                         }
 484                         break;
 485                 }
 486                 dev->stats.tx_packets++;
 487                 sp->tx_old = NEXT_TX(sp->tx_old);
 488                 td->tdma.cntinfo &= ~(HPCDMA_XIU | HPCDMA_XIE);
 489                 td->tdma.cntinfo |= HPCDMA_EOX;
 490                 if (td->skb) {
 491                         dev_kfree_skb_any(td->skb);
 492                         td->skb = NULL;
 493                 }
 494                 dma_sync_desc_dev(dev, td);
 495         }
 496 }
 497
 498 static irqreturn_t sgiseeq_interrupt(int irq, void *dev_id)
 499 {
 500         struct net_device *dev = (struct net_device *) dev_id;
 501         struct sgiseeq_private *sp = netdev_priv(dev);
 502         struct hpc3_ethregs *hregs = sp->hregs;
 503         struct sgiseeq_regs *sregs = sp->sregs;
 504
 505         spin_lock(&sp->tx_lock);
 506
 507         /* Ack the IRQ and set software state. */
 508         hregs->reset = HPC3_ERST_CLRIRQ;
 509
 510         /* Always check for received packets. */
 511         sgiseeq_rx(dev, sp, hregs, sregs);
 512
 513         /* Only check for tx acks if we have something queued. */
 514         if (sp->tx_old != sp->tx_new)
 515                 sgiseeq_tx(dev, sp, hregs, sregs);
 516
 517         if ((TX_BUFFS_AVAIL(sp) > 0) && netif_queue_stopped(dev)) {
 518                 netif_wake_queue(dev);
 519         }
 520         spin_unlock(&sp->tx_lock);
 521
 522         return IRQ_HANDLED;
 523 }
 524
 525 static int sgiseeq_open(struct net_device *dev)
 526 {
 527         struct sgiseeq_private *sp = netdev_priv(dev);
 528         struct sgiseeq_regs *sregs = sp->sregs;
 529         unsigned int irq = dev->irq;
 530         int err;
 531
 532         if (request_irq(irq, sgiseeq_interrupt, 0, sgiseeqstr, dev)) {
 533                 printk(KERN_ERR "Seeq8003: Can't get irq %d\n", dev->irq);
 534                 return -EAGAIN;
 535         }
 536
 537         err = init_seeq(dev, sp, sregs);
 538         if (err)
 539                 goto out_free_irq;
 540
 541         netif_start_queue(dev);
 542
 543         return 0;
 544
 545 out_free_irq:
 546         free_irq(irq, dev);
 547
 548         return err;
 549 }
 550
 551 static int sgiseeq_close(struct net_device *dev)
 552 {
 553         struct sgiseeq_private *sp = netdev_priv(dev);
 554         struct sgiseeq_regs *sregs = sp->sregs;
 555         unsigned int irq = dev->irq;
 556
 557         netif_stop_queue(dev);
 558
 559         /* Shutdown the Seeq. */
 560         reset_hpc3_and_seeq(sp->hregs, sregs);
 561         free_irq(irq, dev);
 562         seeq_purge_ring(dev);
 563
 564         return 0;
 565 }
 566
 567 static inline int sgiseeq_reset(struct net_device *dev)
 568 {
 569         struct sgiseeq_private *sp = netdev_priv(dev);
 570         struct sgiseeq_regs *sregs = sp->sregs;
 571         int err;
 572
 573         err = init_seeq(dev, sp, sregs);
 574         if (err)
 575                 return err;
 576
 577         dev->trans_start = jiffies; /* prevent tx timeout */
 578         netif_wake_queue(dev);
 579
 580         return 0;
 581 }
 582
 583 static int sgiseeq_start_xmit(struct sk_buff *skb, struct net_device *dev)
 584 {
 585         struct sgiseeq_private *sp = netdev_priv(dev);
 586         struct hpc3_ethregs *hregs = sp->hregs;
 587         unsigned long flags;
 588         struct sgiseeq_tx_desc *td;
 589         int len, entry;
 590
 591         spin_lock_irqsave(&sp->tx_lock, flags);
 592
 593         /* Setup... */
 594         len = skb->len;
 595         if (len < ETH_ZLEN) {
 596                 if (skb_padto(skb, ETH_ZLEN)) {
 597                         spin_unlock_irqrestore(&sp->tx_lock, flags);
 598                         return NETDEV_TX_OK;
 599                 }
 600                 len = ETH_ZLEN;
 601         }
 602
 603         dev->stats.tx_bytes += len;
 604         entry = sp->tx_new;
 605         td = &sp->tx_desc[entry];
 606         dma_sync_desc_cpu(dev, td);
 607
 608         /* Create entry.  There are so many races with adding a new
 609          * descriptor to the chain:
 610          * 1) Assume that the HPC is off processing a DMA chain while
 611          *    we are changing all of the following.
 612          * 2) Do no allow the HPC to look at a new descriptor until
 613          *    we have completely set up it's state.  This means, do
 614          *    not clear HPCDMA_EOX in the current last descritptor
 615          *    until the one we are adding looks consistent and could
 616          *    be processes right now.
 617          * 3) The tx interrupt code must notice when we've added a new
 618          *    entry and the HPC got to the end of the chain before we
 619          *    added this new entry and restarted it.
 620          */
 621         td->skb = skb;
 622         td->tdma.pbuf = dma_map_single(dev->dev.parent, skb->data,
 623                                        len, DMA_TO_DEVICE);
 624         td->tdma.cntinfo = (len & HPCDMA_BCNT) |
 625                            HPCDMA_XIU | HPCDMA_EOXP | HPCDMA_XIE | HPCDMA_EOX;
 626         dma_sync_desc_dev(dev, td);
 627         if (sp->tx_old != sp->tx_new) {
 628                 struct sgiseeq_tx_desc *backend;
 629
 630                 backend = &sp->tx_desc[PREV_TX(sp->tx_new)];
 631                 dma_sync_desc_cpu(dev, backend);
 632                 backend->tdma.cntinfo &= ~HPCDMA_EOX;
 633                 dma_sync_desc_dev(dev, backend);
 634         }
 635         sp->tx_new = NEXT_TX(sp->tx_new); /* Advance. */
 636
 637         /* Maybe kick the HPC back into motion. */
 638         if (!(hregs->tx_ctrl & HPC3_ETXCTRL_ACTIVE))
 639                 kick_tx(dev, sp, hregs);
 640
 641         if (!TX_BUFFS_AVAIL(sp))
 642                 netif_stop_queue(dev);
 643         spin_unlock_irqrestore(&sp->tx_lock, flags);
 644
 645         return NETDEV_TX_OK;
 646 }
 647
 648 static void timeout(struct net_device *dev)
 649 {
 650         printk(KERN_NOTICE "%s: transmit timed out, resetting\n", dev->name);
 651         sgiseeq_reset(dev);
 652
 653         dev->trans_start = jiffies; /* prevent tx timeout */
 654         netif_wake_queue(dev);
 655 }
 656
 657 static void sgiseeq_set_multicast(struct net_device *dev)
 658 {
 659         struct sgiseeq_private *sp = netdev_priv(dev);
 660         unsigned char oldmode = sp->mode;
 661
 662         if(dev->flags & IFF_PROMISC)
 663                 sp->mode = SEEQ_RCMD_RANY;
 664         else if ((dev->flags & IFF_ALLMULTI) || !netdev_mc_empty(dev))
 665                 sp->mode = SEEQ_RCMD_RBMCAST;
 666         else
 667                 sp->mode = SEEQ_RCMD_RBCAST;
 668
 669         /* XXX I know this sucks, but is there a better way to reprogram
 670          * XXX the receiver? At least, this shouldn't happen too often.
 671          */
 672
 673         if (oldmode != sp->mode)
 674                 sgiseeq_reset(dev);
 675 }
 676
 677 static inline void setup_tx_ring(struct net_device *dev,
 678                                  struct sgiseeq_tx_desc *buf,
 679                                  int nbufs)
 680 {
 681         struct sgiseeq_private *sp = netdev_priv(dev);
 682         int i = 0;
 683
 684         while (i < (nbufs - 1)) {
 685                 buf[i].tdma.pnext = VIRT_TO_DMA(sp, buf + i + 1);
 686                 buf[i].tdma.pbuf = 0;
 687                 dma_sync_desc_dev(dev, &buf[i]);
 688                 i++;
 689         }
 690         buf[i].tdma.pnext = VIRT_TO_DMA(sp, buf);
 691         dma_sync_desc_dev(dev, &buf[i]);
 692 }
 693
 694 static inline void setup_rx_ring(struct net_device *dev,
 695                                  struct sgiseeq_rx_desc *buf,
 696                                  int nbufs)
 697 {
 698         struct sgiseeq_private *sp = netdev_priv(dev);
 699         int i = 0;
 700
 701         while (i < (nbufs - 1)) {
 702                 buf[i].rdma.pnext = VIRT_TO_DMA(sp, buf + i + 1);
 703                 buf[i].rdma.pbuf = 0;
 704                 dma_sync_desc_dev(dev, &buf[i]);
 705                 i++;
 706         }
 707         buf[i].rdma.pbuf = 0;
 708         buf[i].rdma.pnext = VIRT_TO_DMA(sp, buf);
 709         dma_sync_desc_dev(dev, &buf[i]);
 710 }
 711
 712 static const struct net_device_ops sgiseeq_netdev_ops = {
 713         .ndo_open               = sgiseeq_open,
 714         .ndo_stop               = sgiseeq_close,
 715         .ndo_start_xmit         = sgiseeq_start_xmit,
 716         .ndo_tx_timeout         = timeout,
 717         .ndo_set_multicast_list = sgiseeq_set_multicast,
 718         .ndo_set_mac_address    = sgiseeq_set_mac_address,
 719         .ndo_change_mtu         = eth_change_mtu,
 720         .ndo_validate_addr      = eth_validate_addr,
 721 };
 722
 723 static int __devinit sgiseeq_probe(struct platform_device *pdev)
 724 {
 725         struct sgiseeq_platform_data *pd = pdev->dev.platform_data;
 726         struct hpc3_regs *hpcregs = pd->hpc;
 727         struct sgiseeq_init_block *sr;
 728         unsigned int irq = pd->irq;
 729         struct sgiseeq_private *sp;
 730         struct net_device *dev;
 731         int err;
 732
 733         dev = alloc_etherdev(sizeof (struct sgiseeq_private));
 734         if (!dev) {
 735                 printk(KERN_ERR "Sgiseeq: Etherdev alloc failed, aborting.\n");
 736                 err = -ENOMEM;
 737                 goto err_out;
 738         }
 739
 740         platform_set_drvdata(pdev, dev);
 741         sp = netdev_priv(dev);
 742
 743         /* Make private data page aligned */
 744         sr = dma_alloc_noncoherent(&pdev->dev, sizeof(*sp->srings),
 745                                 &sp->srings_dma, GFP_KERNEL);
 746         if (!sr) {
 747                 printk(KERN_ERR "Sgiseeq: Page alloc failed, aborting.\n");
 748                 err = -ENOMEM;
 749                 goto err_out_free_dev;
 750         }
 751         sp->srings = sr;
 752         sp->rx_desc = sp->srings->rxvector;
 753         sp->tx_desc = sp->srings->txvector;
 754
 755         /* A couple calculations now, saves many cycles later. */
 756         setup_rx_ring(dev, sp->rx_desc, SEEQ_RX_BUFFERS);
 757         setup_tx_ring(dev, sp->tx_desc, SEEQ_TX_BUFFERS);
 758
 759         memcpy(dev->dev_addr, pd->mac, ETH_ALEN);
 760
 761 #ifdef DEBUG
 762         gpriv = sp;
 763         gdev = dev;
 764 #endif
 765         sp->sregs = (struct sgiseeq_regs *) &hpcregs->eth_ext[0];
 766         sp->hregs = &hpcregs->ethregs;
 767         sp->name = sgiseeqstr;
 768         sp->mode = SEEQ_RCMD_RBCAST;
 769
 770         /* Setup PIO and DMA transfer timing */
 771         sp->hregs->pconfig = 0x161;
 772         sp->hregs->dconfig = HPC3_EDCFG_FIRQ | HPC3_EDCFG_FEOP |
 773                              HPC3_EDCFG_FRXDC | HPC3_EDCFG_PTO | 0x026;
 774
 775         /* Setup PIO and DMA transfer timing */
 776         sp->hregs->pconfig = 0x161;
 777         sp->hregs->dconfig = HPC3_EDCFG_FIRQ | HPC3_EDCFG_FEOP |
 778                              HPC3_EDCFG_FRXDC | HPC3_EDCFG_PTO | 0x026;
 779
 780         /* Reset the chip. */
 781         hpc3_eth_reset(sp->hregs);
 782
 783         sp->is_edlc = !(sp->sregs->rw.rregs.collision_tx[0] & 0xff);
 784         if (sp->is_edlc)
 785                 sp->control = SEEQ_CTRL_XCNT | SEEQ_CTRL_ACCNT |
 786                               SEEQ_CTRL_SFLAG | SEEQ_CTRL_ESHORT |
 787                               SEEQ_CTRL_ENCARR;
 788
 789         dev->netdev_ops         = &sgiseeq_netdev_ops;
 790         dev->watchdog_timeo     = (200 * HZ) / 1000;
 791         dev->irq                = irq;
 792
 793         if (register_netdev(dev)) {
 794                 printk(KERN_ERR "Sgiseeq: Cannot register net device, "
 795                        "aborting.\n");
 796                 err = -ENODEV;
 797                 goto err_out_free_page;
 798         }
 799
 800         printk(KERN_INFO "%s: %s %pM\n", dev->name, sgiseeqstr, dev->dev_addr);
 801
 802         return 0;
 803
 804 err_out_free_page:
 805         free_page((unsigned long) sp->srings);
 806 err_out_free_dev:
 807         free_netdev(dev);
 808
 809 err_out:
 810         return err;
 811 }
 812
 813 static int __exit sgiseeq_remove(struct platform_device *pdev)
 814 {
 815         struct net_device *dev = platform_get_drvdata(pdev);
 816         struct sgiseeq_private *sp = netdev_priv(dev);
 817
 818         unregister_netdev(dev);
 819         dma_free_noncoherent(&pdev->dev, sizeof(*sp->srings), sp->srings,
 820                              sp->srings_dma);
 821         free_netdev(dev);
 822         platform_set_drvdata(pdev, NULL);
 823
 824         return 0;
 825 }
 826
 827 static struct platform_driver sgiseeq_driver = {
 828         .probe  = sgiseeq_probe,
 829         .remove = __exit_p(sgiseeq_remove),
 830         .driver = {
 831                 .name   = "sgiseeq",
 832                 .owner  = THIS_MODULE,
 833         }
 834 };
 835
 836 static int __init sgiseeq_module_init(void)
 837 {
 838         if (platform_driver_register(&sgiseeq_driver)) {
 839                 printk(KERN_ERR "Driver registration failed\n");
 840                 return -ENODEV;
 841         }
 842
 843         return 0;
 844 }
 845
 846 static void __exit sgiseeq_module_exit(void)
 847 {
 848         platform_driver_unregister(&sgiseeq_driver);
 849 }
 850
 851 module_init(sgiseeq_module_init);
 852 module_exit(sgiseeq_module_exit);
 853
 854 MODULE_DESCRIPTION("SGI Seeq 8003 driver");
 855 MODULE_AUTHOR("Linux/MIPS Mailing List <linux-mips@linux-mips.org>");
 856 MODULE_LICENSE("GPL");
 857 MODULE_ALIAS("platform:sgiseeq");