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