linux/drivers/net/ethernet/seeq/sgiseeq.c
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   1/*
   2 * sgiseeq.c: Seeq8003 ethernet driver for SGI machines.
   3 *
   4 * Copyright (C) 1996 David S. Miller (davem@davemloft.net)
   5 */
   6
   7#undef DEBUG
   8
   9#include <linux/dma-mapping.h>
  10#include <linux/kernel.h>
  11#include <linux/module.h>
  12#include <linux/slab.h>
  13#include <linux/errno.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
  29static 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 */
  63static int rx_copybreak = 100;
  64
  65#define PAD_SIZE    (128 - sizeof(struct hpc_dma_desc) - sizeof(void *))
  66
  67struct sgiseeq_rx_desc {
  68        volatile struct hpc_dma_desc rdma;
  69        u8 padding[PAD_SIZE];
  70        struct sk_buff *skb;
  71};
  72
  73struct 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 */
  84struct 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
  89struct 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
 112static 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
 118static 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
 124static 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
 131static 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
 141static 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
 149static 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
 160static 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
 178static 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
 218static 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
 241static struct sgiseeq_private *gpriv;
 242static struct net_device *gdev;
 243
 244static 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
 286static 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
 313static 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
 326static 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
 336static 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 (!ether_addr_equal(rd->skb->data + 6, dev->dev_addr)) {
 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                                }
 375memory_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                                        dev->stats.rx_dropped++;
 384                                }
 385                        } else {
 386                                /* Silently drop my own packets */
 387                                newskb = rd->skb;
 388                        }
 389                } else {
 390                        record_rx_errors(dev, pkt_status);
 391                        newskb = rd->skb;
 392                }
 393                rd->skb = newskb;
 394                rd->rdma.pbuf = dma_map_single(dev->dev.parent,
 395                                               newskb->data - 2,
 396                                               PKT_BUF_SZ, DMA_FROM_DEVICE);
 397
 398                /* Return the entry to the ring pool. */
 399                rd->rdma.cntinfo = RCNTINFO_INIT;
 400                sp->rx_new = NEXT_RX(sp->rx_new);
 401                dma_sync_desc_dev(dev, rd);
 402                rd = &sp->rx_desc[sp->rx_new];
 403                dma_sync_desc_cpu(dev, rd);
 404        }
 405        dma_sync_desc_cpu(dev, &sp->rx_desc[orig_end]);
 406        sp->rx_desc[orig_end].rdma.cntinfo &= ~(HPCDMA_EOR);
 407        dma_sync_desc_dev(dev, &sp->rx_desc[orig_end]);
 408        dma_sync_desc_cpu(dev, &sp->rx_desc[PREV_RX(sp->rx_new)]);
 409        sp->rx_desc[PREV_RX(sp->rx_new)].rdma.cntinfo |= HPCDMA_EOR;
 410        dma_sync_desc_dev(dev, &sp->rx_desc[PREV_RX(sp->rx_new)]);
 411        rx_maybe_restart(sp, hregs, sregs);
 412}
 413
 414static inline void tx_maybe_reset_collisions(struct sgiseeq_private *sp,
 415                                             struct sgiseeq_regs *sregs)
 416{
 417        if (sp->is_edlc) {
 418                sregs->rw.wregs.control = sp->control & ~(SEEQ_CTRL_XCNT);
 419                sregs->rw.wregs.control = sp->control;
 420        }
 421}
 422
 423static inline void kick_tx(struct net_device *dev,
 424                           struct sgiseeq_private *sp,
 425                           struct hpc3_ethregs *hregs)
 426{
 427        struct sgiseeq_tx_desc *td;
 428        int i = sp->tx_old;
 429
 430        /* If the HPC aint doin nothin, and there are more packets
 431         * with ETXD cleared and XIU set we must make very certain
 432         * that we restart the HPC else we risk locking up the
 433         * adapter.  The following code is only safe iff the HPCDMA
 434         * is not active!
 435         */
 436        td = &sp->tx_desc[i];
 437        dma_sync_desc_cpu(dev, td);
 438        while ((td->tdma.cntinfo & (HPCDMA_XIU | HPCDMA_ETXD)) ==
 439              (HPCDMA_XIU | HPCDMA_ETXD)) {
 440                i = NEXT_TX(i);
 441                td = &sp->tx_desc[i];
 442                dma_sync_desc_cpu(dev, td);
 443        }
 444        if (td->tdma.cntinfo & HPCDMA_XIU) {
 445                hregs->tx_ndptr = VIRT_TO_DMA(sp, td);
 446                hregs->tx_ctrl = HPC3_ETXCTRL_ACTIVE;
 447        }
 448}
 449
 450static inline void sgiseeq_tx(struct net_device *dev, struct sgiseeq_private *sp,
 451                              struct hpc3_ethregs *hregs,
 452                              struct sgiseeq_regs *sregs)
 453{
 454        struct sgiseeq_tx_desc *td;
 455        unsigned long status = hregs->tx_ctrl;
 456        int j;
 457
 458        tx_maybe_reset_collisions(sp, sregs);
 459
 460        if (!(status & (HPC3_ETXCTRL_ACTIVE | SEEQ_TSTAT_PTRANS))) {
 461                /* Oops, HPC detected some sort of error. */
 462                if (status & SEEQ_TSTAT_R16)
 463                        dev->stats.tx_aborted_errors++;
 464                if (status & SEEQ_TSTAT_UFLOW)
 465                        dev->stats.tx_fifo_errors++;
 466                if (status & SEEQ_TSTAT_LCLS)
 467                        dev->stats.collisions++;
 468        }
 469
 470        /* Ack 'em... */
 471        for (j = sp->tx_old; j != sp->tx_new; j = NEXT_TX(j)) {
 472                td = &sp->tx_desc[j];
 473
 474                dma_sync_desc_cpu(dev, td);
 475                if (!(td->tdma.cntinfo & (HPCDMA_XIU)))
 476                        break;
 477                if (!(td->tdma.cntinfo & (HPCDMA_ETXD))) {
 478                        if (!(status & HPC3_ETXCTRL_ACTIVE)) {
 479                                hregs->tx_ndptr = VIRT_TO_DMA(sp, td);
 480                                hregs->tx_ctrl = HPC3_ETXCTRL_ACTIVE;
 481                        }
 482                        break;
 483                }
 484                dev->stats.tx_packets++;
 485                sp->tx_old = NEXT_TX(sp->tx_old);
 486                td->tdma.cntinfo &= ~(HPCDMA_XIU | HPCDMA_XIE);
 487                td->tdma.cntinfo |= HPCDMA_EOX;
 488                if (td->skb) {
 489                        dev_kfree_skb_any(td->skb);
 490                        td->skb = NULL;
 491                }
 492                dma_sync_desc_dev(dev, td);
 493        }
 494}
 495
 496static irqreturn_t sgiseeq_interrupt(int irq, void *dev_id)
 497{
 498        struct net_device *dev = (struct net_device *) dev_id;
 499        struct sgiseeq_private *sp = netdev_priv(dev);
 500        struct hpc3_ethregs *hregs = sp->hregs;
 501        struct sgiseeq_regs *sregs = sp->sregs;
 502
 503        spin_lock(&sp->tx_lock);
 504
 505        /* Ack the IRQ and set software state. */
 506        hregs->reset = HPC3_ERST_CLRIRQ;
 507
 508        /* Always check for received packets. */
 509        sgiseeq_rx(dev, sp, hregs, sregs);
 510
 511        /* Only check for tx acks if we have something queued. */
 512        if (sp->tx_old != sp->tx_new)
 513                sgiseeq_tx(dev, sp, hregs, sregs);
 514
 515        if ((TX_BUFFS_AVAIL(sp) > 0) && netif_queue_stopped(dev)) {
 516                netif_wake_queue(dev);
 517        }
 518        spin_unlock(&sp->tx_lock);
 519
 520        return IRQ_HANDLED;
 521}
 522
 523static int sgiseeq_open(struct net_device *dev)
 524{
 525        struct sgiseeq_private *sp = netdev_priv(dev);
 526        struct sgiseeq_regs *sregs = sp->sregs;
 527        unsigned int irq = dev->irq;
 528        int err;
 529
 530        if (request_irq(irq, sgiseeq_interrupt, 0, sgiseeqstr, dev)) {
 531                printk(KERN_ERR "Seeq8003: Can't get irq %d\n", dev->irq);
 532                return -EAGAIN;
 533        }
 534
 535        err = init_seeq(dev, sp, sregs);
 536        if (err)
 537                goto out_free_irq;
 538
 539        netif_start_queue(dev);
 540
 541        return 0;
 542
 543out_free_irq:
 544        free_irq(irq, dev);
 545
 546        return err;
 547}
 548
 549static int sgiseeq_close(struct net_device *dev)
 550{
 551        struct sgiseeq_private *sp = netdev_priv(dev);
 552        struct sgiseeq_regs *sregs = sp->sregs;
 553        unsigned int irq = dev->irq;
 554
 555        netif_stop_queue(dev);
 556
 557        /* Shutdown the Seeq. */
 558        reset_hpc3_and_seeq(sp->hregs, sregs);
 559        free_irq(irq, dev);
 560        seeq_purge_ring(dev);
 561
 562        return 0;
 563}
 564
 565static inline int sgiseeq_reset(struct net_device *dev)
 566{
 567        struct sgiseeq_private *sp = netdev_priv(dev);
 568        struct sgiseeq_regs *sregs = sp->sregs;
 569        int err;
 570
 571        err = init_seeq(dev, sp, sregs);
 572        if (err)
 573                return err;
 574
 575        netif_trans_update(dev); /* prevent tx timeout */
 576        netif_wake_queue(dev);
 577
 578        return 0;
 579}
 580
 581static int sgiseeq_start_xmit(struct sk_buff *skb, struct net_device *dev)
 582{
 583        struct sgiseeq_private *sp = netdev_priv(dev);
 584        struct hpc3_ethregs *hregs = sp->hregs;
 585        unsigned long flags;
 586        struct sgiseeq_tx_desc *td;
 587        int len, entry;
 588
 589        spin_lock_irqsave(&sp->tx_lock, flags);
 590
 591        /* Setup... */
 592        len = skb->len;
 593        if (len < ETH_ZLEN) {
 594                if (skb_padto(skb, ETH_ZLEN)) {
 595                        spin_unlock_irqrestore(&sp->tx_lock, flags);
 596                        return NETDEV_TX_OK;
 597                }
 598                len = ETH_ZLEN;
 599        }
 600
 601        dev->stats.tx_bytes += len;
 602        entry = sp->tx_new;
 603        td = &sp->tx_desc[entry];
 604        dma_sync_desc_cpu(dev, td);
 605
 606        /* Create entry.  There are so many races with adding a new
 607         * descriptor to the chain:
 608         * 1) Assume that the HPC is off processing a DMA chain while
 609         *    we are changing all of the following.
 610         * 2) Do no allow the HPC to look at a new descriptor until
 611         *    we have completely set up it's state.  This means, do
 612         *    not clear HPCDMA_EOX in the current last descritptor
 613         *    until the one we are adding looks consistent and could
 614         *    be processes right now.
 615         * 3) The tx interrupt code must notice when we've added a new
 616         *    entry and the HPC got to the end of the chain before we
 617         *    added this new entry and restarted it.
 618         */
 619        td->skb = skb;
 620        td->tdma.pbuf = dma_map_single(dev->dev.parent, skb->data,
 621                                       len, DMA_TO_DEVICE);
 622        td->tdma.cntinfo = (len & HPCDMA_BCNT) |
 623                           HPCDMA_XIU | HPCDMA_EOXP | HPCDMA_XIE | HPCDMA_EOX;
 624        dma_sync_desc_dev(dev, td);
 625        if (sp->tx_old != sp->tx_new) {
 626                struct sgiseeq_tx_desc *backend;
 627
 628                backend = &sp->tx_desc[PREV_TX(sp->tx_new)];
 629                dma_sync_desc_cpu(dev, backend);
 630                backend->tdma.cntinfo &= ~HPCDMA_EOX;
 631                dma_sync_desc_dev(dev, backend);
 632        }
 633        sp->tx_new = NEXT_TX(sp->tx_new); /* Advance. */
 634
 635        /* Maybe kick the HPC back into motion. */
 636        if (!(hregs->tx_ctrl & HPC3_ETXCTRL_ACTIVE))
 637                kick_tx(dev, sp, hregs);
 638
 639        if (!TX_BUFFS_AVAIL(sp))
 640                netif_stop_queue(dev);
 641        spin_unlock_irqrestore(&sp->tx_lock, flags);
 642
 643        return NETDEV_TX_OK;
 644}
 645
 646static void timeout(struct net_device *dev)
 647{
 648        printk(KERN_NOTICE "%s: transmit timed out, resetting\n", dev->name);
 649        sgiseeq_reset(dev);
 650
 651        netif_trans_update(dev); /* prevent tx timeout */
 652        netif_wake_queue(dev);
 653}
 654
 655static void sgiseeq_set_multicast(struct net_device *dev)
 656{
 657        struct sgiseeq_private *sp = netdev_priv(dev);
 658        unsigned char oldmode = sp->mode;
 659
 660        if(dev->flags & IFF_PROMISC)
 661                sp->mode = SEEQ_RCMD_RANY;
 662        else if ((dev->flags & IFF_ALLMULTI) || !netdev_mc_empty(dev))
 663                sp->mode = SEEQ_RCMD_RBMCAST;
 664        else
 665                sp->mode = SEEQ_RCMD_RBCAST;
 666
 667        /* XXX I know this sucks, but is there a better way to reprogram
 668         * XXX the receiver? At least, this shouldn't happen too often.
 669         */
 670
 671        if (oldmode != sp->mode)
 672                sgiseeq_reset(dev);
 673}
 674
 675static inline void setup_tx_ring(struct net_device *dev,
 676                                 struct sgiseeq_tx_desc *buf,
 677                                 int nbufs)
 678{
 679        struct sgiseeq_private *sp = netdev_priv(dev);
 680        int i = 0;
 681
 682        while (i < (nbufs - 1)) {
 683                buf[i].tdma.pnext = VIRT_TO_DMA(sp, buf + i + 1);
 684                buf[i].tdma.pbuf = 0;
 685                dma_sync_desc_dev(dev, &buf[i]);
 686                i++;
 687        }
 688        buf[i].tdma.pnext = VIRT_TO_DMA(sp, buf);
 689        dma_sync_desc_dev(dev, &buf[i]);
 690}
 691
 692static inline void setup_rx_ring(struct net_device *dev,
 693                                 struct sgiseeq_rx_desc *buf,
 694                                 int nbufs)
 695{
 696        struct sgiseeq_private *sp = netdev_priv(dev);
 697        int i = 0;
 698
 699        while (i < (nbufs - 1)) {
 700                buf[i].rdma.pnext = VIRT_TO_DMA(sp, buf + i + 1);
 701                buf[i].rdma.pbuf = 0;
 702                dma_sync_desc_dev(dev, &buf[i]);
 703                i++;
 704        }
 705        buf[i].rdma.pbuf = 0;
 706        buf[i].rdma.pnext = VIRT_TO_DMA(sp, buf);
 707        dma_sync_desc_dev(dev, &buf[i]);
 708}
 709
 710static const struct net_device_ops sgiseeq_netdev_ops = {
 711        .ndo_open               = sgiseeq_open,
 712        .ndo_stop               = sgiseeq_close,
 713        .ndo_start_xmit         = sgiseeq_start_xmit,
 714        .ndo_tx_timeout         = timeout,
 715        .ndo_set_rx_mode        = sgiseeq_set_multicast,
 716        .ndo_set_mac_address    = sgiseeq_set_mac_address,
 717        .ndo_change_mtu         = eth_change_mtu,
 718        .ndo_validate_addr      = eth_validate_addr,
 719};
 720
 721static int sgiseeq_probe(struct platform_device *pdev)
 722{
 723        struct sgiseeq_platform_data *pd = dev_get_platdata(&pdev->dev);
 724        struct hpc3_regs *hpcregs = pd->hpc;
 725        struct sgiseeq_init_block *sr;
 726        unsigned int irq = pd->irq;
 727        struct sgiseeq_private *sp;
 728        struct net_device *dev;
 729        int err;
 730
 731        dev = alloc_etherdev(sizeof (struct sgiseeq_private));
 732        if (!dev) {
 733                err = -ENOMEM;
 734                goto err_out;
 735        }
 736
 737        platform_set_drvdata(pdev, dev);
 738        sp = netdev_priv(dev);
 739
 740        /* Make private data page aligned */
 741        sr = dma_alloc_noncoherent(&pdev->dev, sizeof(*sp->srings),
 742                                &sp->srings_dma, GFP_KERNEL);
 743        if (!sr) {
 744                printk(KERN_ERR "Sgiseeq: Page alloc failed, aborting.\n");
 745                err = -ENOMEM;
 746                goto err_out_free_dev;
 747        }
 748        sp->srings = sr;
 749        sp->rx_desc = sp->srings->rxvector;
 750        sp->tx_desc = sp->srings->txvector;
 751        spin_lock_init(&sp->tx_lock);
 752
 753        /* A couple calculations now, saves many cycles later. */
 754        setup_rx_ring(dev, sp->rx_desc, SEEQ_RX_BUFFERS);
 755        setup_tx_ring(dev, sp->tx_desc, SEEQ_TX_BUFFERS);
 756
 757        memcpy(dev->dev_addr, pd->mac, ETH_ALEN);
 758
 759#ifdef DEBUG
 760        gpriv = sp;
 761        gdev = dev;
 762#endif
 763        sp->sregs = (struct sgiseeq_regs *) &hpcregs->eth_ext[0];
 764        sp->hregs = &hpcregs->ethregs;
 765        sp->name = sgiseeqstr;
 766        sp->mode = SEEQ_RCMD_RBCAST;
 767
 768        /* Setup PIO and DMA transfer timing */
 769        sp->hregs->pconfig = 0x161;
 770        sp->hregs->dconfig = HPC3_EDCFG_FIRQ | HPC3_EDCFG_FEOP |
 771                             HPC3_EDCFG_FRXDC | HPC3_EDCFG_PTO | 0x026;
 772
 773        /* Setup PIO and DMA transfer timing */
 774        sp->hregs->pconfig = 0x161;
 775        sp->hregs->dconfig = HPC3_EDCFG_FIRQ | HPC3_EDCFG_FEOP |
 776                             HPC3_EDCFG_FRXDC | HPC3_EDCFG_PTO | 0x026;
 777
 778        /* Reset the chip. */
 779        hpc3_eth_reset(sp->hregs);
 780
 781        sp->is_edlc = !(sp->sregs->rw.rregs.collision_tx[0] & 0xff);
 782        if (sp->is_edlc)
 783                sp->control = SEEQ_CTRL_XCNT | SEEQ_CTRL_ACCNT |
 784                              SEEQ_CTRL_SFLAG | SEEQ_CTRL_ESHORT |
 785                              SEEQ_CTRL_ENCARR;
 786
 787        dev->netdev_ops         = &sgiseeq_netdev_ops;
 788        dev->watchdog_timeo     = (200 * HZ) / 1000;
 789        dev->irq                = irq;
 790
 791        if (register_netdev(dev)) {
 792                printk(KERN_ERR "Sgiseeq: Cannot register net device, "
 793                       "aborting.\n");
 794                err = -ENODEV;
 795                goto err_out_free_page;
 796        }
 797
 798        printk(KERN_INFO "%s: %s %pM\n", dev->name, sgiseeqstr, dev->dev_addr);
 799
 800        return 0;
 801
 802err_out_free_page:
 803        free_page((unsigned long) sp->srings);
 804err_out_free_dev:
 805        free_netdev(dev);
 806
 807err_out:
 808        return err;
 809}
 810
 811static int __exit sgiseeq_remove(struct platform_device *pdev)
 812{
 813        struct net_device *dev = platform_get_drvdata(pdev);
 814        struct sgiseeq_private *sp = netdev_priv(dev);
 815
 816        unregister_netdev(dev);
 817        dma_free_noncoherent(&pdev->dev, sizeof(*sp->srings), sp->srings,
 818                             sp->srings_dma);
 819        free_netdev(dev);
 820
 821        return 0;
 822}
 823
 824static struct platform_driver sgiseeq_driver = {
 825        .probe  = sgiseeq_probe,
 826        .remove = __exit_p(sgiseeq_remove),
 827        .driver = {
 828                .name   = "sgiseeq",
 829        }
 830};
 831
 832module_platform_driver(sgiseeq_driver);
 833
 834MODULE_DESCRIPTION("SGI Seeq 8003 driver");
 835MODULE_AUTHOR("Linux/MIPS Mailing List <linux-mips@linux-mips.org>");
 836MODULE_LICENSE("GPL");
 837MODULE_ALIAS("platform:sgiseeq");
 838