drivers/net/meth.c

   1 /*
   2  * meth.c -- O2 Builtin 10/100 Ethernet driver
   3  *
   4  * Copyright (C) 2001 Ilya Volynets
   5  *
   6  *      This program is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU General Public License
   8  *      as published by the Free Software Foundation; either version
   9  *      2 of the License, or (at your option) any later version.
  10  */
  11 #include <linux/module.h>
  12 #include <linux/init.h>
  13
  14 #include <linux/sched.h>
  15 #include <linux/kernel.h> /* printk() */
  16 #include <linux/delay.h>
  17 #include <linux/slab.h>
  18 #include <linux/errno.h>  /* error codes */
  19 #include <linux/types.h>  /* size_t */
  20 #include <linux/interrupt.h> /* mark_bh */
  21
  22 #include <linux/in.h>
  23 #include <linux/netdevice.h>   /* struct device, and other headers */
  24 #include <linux/etherdevice.h> /* eth_type_trans */
  25 #include <linux/ip.h>          /* struct iphdr */
  26 #include <linux/tcp.h>         /* struct tcphdr */
  27 #include <linux/skbuff.h>
  28 #include <linux/mii.h> /*MII definitions */
  29
  30 #include <asm/ip32/crime.h>
  31 #include <asm/ip32/mace.h>
  32 #include <asm/ip32/ip32_ints.h>
  33
  34 #include <linux/slab.h>
  35 #include <asm/io.h>
  36 #include <asm/scatterlist.h>
  37 #include <linux/device.h> /* struct device, et al */
  38 #include <linux/dma-mapping.h>
  39
  40 #include "meth.h"
  41
  42 #include <linux/in6.h>
  43 #include <asm/checksum.h>
  44
  45 #ifndef MFE_DEBUG
  46 #define MFE_DEBUG 0
  47 #endif
  48
  49 #if MFE_DEBUG>=1
  50 #define DPRINTK(str,args...) printk (KERN_DEBUG "meth(%ld): %s: " str, jiffies, __FUNCTION__ , ## args)
  51 #define MFE_RX_DEBUG 2
  52 #else
  53 #define DPRINTK(str,args...)
  54 #define MFE_RX_DEBUG 0
  55 #endif
  56
  57
  58 static const char *meth_str="SGI O2 Fast Ethernet";
  59 MODULE_AUTHOR("Ilya Volynets <ilya@theIlya.com>");
  60 MODULE_DESCRIPTION("SGI O2 Builtin Fast Ethernet driver");
  61
  62 #define HAVE_TX_TIMEOUT
  63 /* The maximum time waited (in jiffies) before assuming a Tx failed. (400ms) */
  64 #define TX_TIMEOUT (400*HZ/1000)
  65
  66 #ifdef HAVE_TX_TIMEOUT
  67 static int timeout = TX_TIMEOUT;
  68 MODULE_PARM(timeout, "i");
  69 #endif
  70
  71 /*
  72  * This structure is private to each device. It is used to pass
  73  * packets in and out, so there is place for a packet
  74  */
  75
  76 typedef struct meth_private {
  77         struct net_device_stats stats;
  78         volatile struct meth_regs *regs;
  79         u64 mode; /* in-memory copy of MAC control register */
  80         int  phy_addr; /* address of phy, used by mdio_* functions, initialized in mdio_probe*/
  81         tx_packet *tx_ring;
  82         dma_addr_t tx_ring_dma;
  83         int free_space;
  84         struct sk_buff *tx_skbs[TX_RING_ENTRIES];
  85         dma_addr_t      tx_skb_dmas[TX_RING_ENTRIES];
  86         int tx_read,tx_write;
  87         int tx_count;
  88
  89         rx_packet *rx_ring[RX_RING_ENTRIES];
  90         dma_addr_t rx_ring_dmas[RX_RING_ENTRIES];
  91         int rx_write;
  92
  93         spinlock_t meth_lock;
  94 } meth_private;
  95
  96 void meth_tx_timeout (struct net_device *dev);
  97 irqreturn_t meth_interrupt(int irq, void *dev_id, struct pt_regs *pregs);
  98
  99 /* global, initialized in ip32-setup.c */
 100 char o2meth_eaddr[8]={0,0,0,0,0,0,0,0};
 101
 102 static inline void load_eaddr(struct net_device *dev,
 103                               volatile struct meth_regs *regs)
 104 {
 105         int i;
 106         DPRINTK("Loading MAC Address: %02x:%02x:%02x:%02x:%02x:%02x\n",
 107                 (int)o2meth_eaddr[0]&0xFF,(int)o2meth_eaddr[1]&0xFF,(int)o2meth_eaddr[2]&0xFF,
 108                 (int)o2meth_eaddr[3]&0xFF,(int)o2meth_eaddr[4]&0xFF,(int)o2meth_eaddr[5]&0xFF);
 109         for (i=0; i<6; i++)
 110                 dev->dev_addr[i]=o2meth_eaddr[i];
 111         regs->mac_addr=(*(u64*)o2meth_eaddr)>>16;
 112 }
 113
 114 /*
 115  *Waits for BUSY status of mdio bus to clear
 116  */
 117 #define WAIT_FOR_PHY(___regs, ___rval)                  \
 118         while((___rval=___regs->phy_data)&MDIO_BUSY){   \
 119                 udelay(25);                             \
 120         }
 121 /*read phy register, return value read */
 122 static int mdio_read(meth_private *priv,int phyreg)
 123 {
 124         volatile meth_regs* regs=priv->regs;
 125         volatile u32 rval;
 126         WAIT_FOR_PHY(regs,rval);
 127         regs->phy_registers=(priv->phy_addr<<5)|(phyreg&0x1f);
 128         udelay(25);
 129         regs->phy_trans_go=1;
 130         udelay(25);
 131         WAIT_FOR_PHY(regs,rval);
 132         return rval&MDIO_DATA_MASK;
 133 }
 134
 135 static int mdio_probe(meth_private *priv)
 136 {
 137         int i, p2, p3;
 138         DPRINTK("Detecting PHY kind\n");
 139         /* check if phy is detected already */
 140         if(priv->phy_addr>=0&&priv->phy_addr<32)
 141                 return 0;
 142         spin_lock(&priv->meth_lock);
 143         for (i=0;i<32;++i){
 144                 priv->phy_addr=(char)i;
 145                 p2=mdio_read(priv,2);
 146 #ifdef MFE_DEBUG
 147                 p3=mdio_read(priv,3);
 148                 switch ((p2<<12)|(p3>>4)){
 149                 case PHY_QS6612X:
 150                         DPRINTK("PHY is QS6612X\n");
 151                         break;
 152                 case PHY_ICS1889:
 153                         DPRINTK("PHY is ICS1889\n");
 154                         break;
 155                 case PHY_ICS1890:
 156                         DPRINTK("PHY is ICS1890\n");
 157                         break;
 158                 case PHY_DP83840:
 159                         DPRINTK("PHY is DP83840\n");
 160                         break;
 161                 }
 162 #endif
 163                 if(p2!=0xffff&&p2!=0x0000){
 164                         DPRINTK("PHY code: %x\n",(p2<<12)|(p3>>4));
 165                         break;
 166                 }
 167         }
 168         spin_unlock(&priv->meth_lock);
 169         if(priv->phy_addr<32) {
 170                 return 0;
 171         }
 172         DPRINTK("Oopsie! PHY is not known!\n");
 173         priv->phy_addr=-1;
 174         return -ENODEV;
 175 }
 176
 177 static void meth_check_link(struct net_device *dev)
 178 {
 179         struct meth_private *priv = (struct meth_private *) dev->priv;
 180         int mii_partner = mdio_read(priv, 5);
 181         int mii_advertising = mdio_read(priv, 4);
 182         int negotiated = mii_advertising & mii_partner;
 183         int duplex, speed;
 184
 185         if (mii_partner == 0xffff)
 186                 return;
 187
 188         duplex = ((negotiated & 0x0100) || (negotiated & 0x01C0) == 0x0040)?METH_PHY_FDX:0;
 189         speed = (negotiated & 0x0380)?METH_100MBIT:0;
 190
 191         if ((priv->mode & METH_PHY_FDX) ^ duplex)
 192         {
 193                 DPRINTK("Setting %s-duplex\n", duplex ? "full" : "half");
 194                 if (duplex)
 195                         priv->mode |= METH_PHY_FDX;
 196                 else
 197                         priv->mode &= ~METH_PHY_FDX;
 198                 priv->regs->mac_ctrl = priv->mode;
 199         }
 200
 201         if ((priv->mode & METH_100MBIT) ^ speed)
 202         {
 203                 DPRINTK("Setting %dMbs mode\n", speed ? 100 : 10);
 204                 if (duplex)
 205                         priv->mode |= METH_100MBIT;
 206                 else
 207                         priv->mode &= ~METH_100MBIT;
 208                 priv->regs->mac_ctrl = priv->mode;
 209         }
 210 }
 211
 212
 213 static int meth_init_tx_ring(meth_private *priv)
 214 {
 215         /* Init TX ring */
 216         DPRINTK("Initializing TX ring\n");
 217         priv->tx_ring = dma_alloc_coherent(NULL, TX_RING_BUFFER_SIZE,
 218                                            &priv->tx_ring_dma, GFP_ATOMIC);
 219         if (!priv->tx_ring)
 220                 return -ENOMEM;
 221         memset(priv->tx_ring, 0, TX_RING_BUFFER_SIZE);
 222         priv->tx_count = priv->tx_read = priv->tx_write = 0;
 223         priv->regs->tx_ring_base = priv->tx_ring_dma;
 224         priv->free_space = TX_RING_ENTRIES;
 225         /* Now init skb save area */
 226         memset(priv->tx_skbs,0,sizeof(priv->tx_skbs));
 227         memset(priv->tx_skb_dmas,0,sizeof(priv->tx_skb_dmas));
 228         DPRINTK("Done with TX ring init\n");
 229         return 0;
 230 }
 231
 232 static int meth_init_rx_ring(meth_private *priv)
 233 {
 234         int i;
 235         for(i=0;i<RX_RING_ENTRIES;i++){
 236                 priv->rx_ring[i] = dma_alloc_coherent(NULL, METH_RX_BUFF_SIZE,
 237                                                       &priv->rx_ring_dmas[i],0);
 238                 /* I'll need to re-sync it after each RX */
 239                 priv->regs->rx_fifo=priv->rx_ring_dmas[i];
 240         }
 241         priv->rx_write = 0;
 242         DPRINTK("Done with RX ring\n");
 243         return 0;
 244 }
 245 static void meth_free_tx_ring(meth_private *priv)
 246 {
 247         int i;
 248
 249         /* Remove any pending skb */
 250         for (i = 0; i < TX_RING_ENTRIES; i++) {
 251                 if (priv->tx_skbs[i])
 252                         dev_kfree_skb(priv->tx_skbs[i]);
 253                 priv->tx_skbs[i] = NULL;
 254         }
 255         dma_free_coherent(NULL, TX_RING_BUFFER_SIZE, priv->tx_ring,
 256                           priv->tx_ring_dma);
 257 }
 258 static void meth_free_rx_ring(meth_private *priv)
 259 {
 260         int i;
 261
 262         for(i=0;i<RX_RING_ENTRIES;i++)
 263                 dma_free_coherent(NULL, METH_RX_BUFF_SIZE, priv->rx_ring[i],
 264                                   priv->rx_ring_dmas[i]);
 265 }
 266
 267 int meth_reset(struct net_device *dev)
 268 {
 269         struct meth_private *priv = (struct meth_private *) dev->priv;
 270
 271         /* Reset card */
 272         priv->regs->mac_ctrl = SGI_MAC_RESET;
 273         priv->regs->mac_ctrl = 0;
 274         udelay(25);
 275
 276         /* Load ethernet address */
 277         load_eaddr(dev, priv->regs);
 278         /* Should load some "errata", but later */
 279
 280         /* Check for device */
 281         if(mdio_probe(priv) < 0) {
 282                 DPRINTK("Unable to find PHY\n");
 283                 return -ENODEV;
 284         }
 285
 286         /* Initial mode -- 10|Half-duplex|Accept normal packets */
 287         priv->mode=METH_ACCEPT_MCAST|METH_DEFAULT_IPG;
 288         if(dev->flags | IFF_PROMISC)
 289                 priv->mode |= METH_PROMISC;
 290         priv->regs->mac_ctrl = priv->mode;
 291
 292         /* Autonegociate speed and duplex mode */
 293         meth_check_link(dev);
 294
 295         /* Now set dma control, but don't enable DMA, yet */
 296         priv->regs->dma_ctrl= (4 << METH_RX_OFFSET_SHIFT) |
 297                 (RX_RING_ENTRIES << METH_RX_DEPTH_SHIFT);
 298
 299         return(0);
 300 }
 301
 302 /*============End Helper Routines=====================*/
 303
 304 /*
 305  * Open and close
 306  */
 307
 308 int meth_open(struct net_device *dev)
 309 {
 310         meth_private *priv=dev->priv;
 311         volatile meth_regs *regs=priv->regs;
 312         int ret;
 313
 314         /* Initialize the hardware */
 315         if((ret=meth_reset(dev)) < 0)
 316                 return ret;
 317
 318         /* Allocate the ring buffers */
 319         if((ret=meth_init_tx_ring(priv))<0||(ret=meth_init_rx_ring(priv))<0){
 320                 meth_free_tx_ring(priv);
 321                 meth_free_rx_ring(priv);
 322                 return ret;
 323         }
 324
 325         DPRINTK("Will set dma_ctl now\n");
 326         /* Start DMA */
 327         regs->dma_ctrl|=
 328                 METH_DMA_TX_EN|/*METH_DMA_TX_INT_EN|*/
 329                 METH_DMA_RX_EN|METH_DMA_RX_INT_EN;
 330
 331         if(request_irq(dev->irq,meth_interrupt,SA_SHIRQ,meth_str,dev)){
 332                 printk(KERN_ERR "%s: Can't get irq %d\n", dev->name, dev->irq);
 333                 return -EAGAIN;
 334         }
 335         DPRINTK("About to start queue\n");
 336         netif_start_queue(dev);
 337         DPRINTK("Opened... DMA control=0x%08lx\n", regs->dma_ctrl);
 338         return 0;
 339 }
 340
 341 int meth_release(struct net_device *dev)
 342 {
 343         meth_private *priv=dev->priv;
 344         netif_stop_queue(dev); /* can't transmit any more */
 345         /* shut down dma */
 346         ((meth_private*)(dev->priv))->regs->dma_ctrl&=
 347                 ~(METH_DMA_TX_EN|METH_DMA_TX_INT_EN|
 348                   METH_DMA_RX_EN|METH_DMA_RX_INT_EN);
 349         free_irq(dev->irq, dev);
 350         meth_free_tx_ring(priv);
 351         meth_free_rx_ring(priv);
 352         return 0;
 353 }
 354
 355 /*
 356  * Configuration changes (passed on by ifconfig)
 357  */
 358 int meth_config(struct net_device *dev, struct ifmap *map)
 359 {
 360         if (dev->flags & IFF_UP) /* can't act on a running interface */
 361                 return -EBUSY;
 362
 363         /* Don't allow changing the I/O address */
 364         if (map->base_addr != dev->base_addr) {
 365                 printk(KERN_WARNING "meth: Can't change I/O address\n");
 366                 return -EOPNOTSUPP;
 367         }
 368
 369         /* Don't allow changing the IRQ */
 370         if (map->irq != dev->irq) {
 371                 printk(KERN_WARNING "meth: Can't change IRQ\n");
 372                 return -EOPNOTSUPP;
 373         }
 374         DPRINTK("Configured\n");
 375
 376         /* ignore other fields */
 377         return 0;
 378 }
 379
 380 /*
 381  * Receive a packet: retrieve, encapsulate and pass over to upper levels
 382  */
 383 void meth_rx(struct net_device* dev)
 384 {
 385         struct sk_buff *skb;
 386         struct meth_private *priv = (struct meth_private *) dev->priv;
 387         rx_packet *rxb;
 388         int twptr=priv->rx_write;
 389         u64 status;
 390         spin_lock(&(priv->meth_lock));
 391         while ((status=(rxb=priv->rx_ring[priv->rx_write])->status.raw)&0x8000000000000000)
 392         {
 393                 int len=(status&0xFFFF) - 4; /* omit CRC */
 394                 /* length sanity check */
 395                 if(len < 60 || len > 1518) {
 396                         printk(KERN_DEBUG "%s: bogus packet size: %d, status=%#2lx.\n",
 397                                dev->name, priv->rx_write, rxb->status.raw);
 398                         priv->stats.rx_errors++;
 399                         priv->stats.rx_length_errors++;
 400                 }
 401                 if(!(status&METH_RX_STATUS_ERRORS)){
 402                         skb=alloc_skb(len+2,GFP_ATOMIC);/* Should be atomic -- we are in interrupt */
 403                         if(!skb){
 404                                 /* Ouch! No memory! Drop packet on the floor */
 405                                 priv->stats.rx_dropped++;
 406                         } else {
 407                                 skb_reserve(skb, 2); /* align IP on 16B boundary */
 408                                 memcpy(skb_put(skb, len), rxb->buf, len);
 409                                 /* Write metadata, and then pass to the receive level */
 410                                 skb->dev = dev;
 411                                 skb->protocol = eth_type_trans(skb, dev);
 412
 413                                 dev->last_rx = jiffies;
 414                                 priv->stats.rx_packets++;
 415                                 priv->stats.rx_bytes+=len;
 416                                 netif_rx(skb);
 417                         }
 418                 } else {
 419                         printk(KERN_WARNING "meth: RX error: status=0x%016lx\n",status);
 420                         if(status&METH_RX_ST_RCV_CODE_VIOLATION)
 421                                 printk(KERN_WARNING "Receive Code Violation\n");
 422                         if(status&METH_RX_ST_CRC_ERR)
 423                                 printk(KERN_WARNING "CRC error\n");
 424                         if(status&METH_RX_ST_INV_PREAMBLE_CTX)
 425                                 printk(KERN_WARNING "Invalid Preamble Context\n");
 426                         if(status&METH_RX_ST_LONG_EVT_SEEN)
 427                                 printk(KERN_WARNING "Long Event Seen...\n");
 428                         if(status&METH_RX_ST_BAD_PACKET)
 429                                 printk(KERN_WARNING "Bad Packet\n");
 430                         if(status&METH_RX_ST_CARRIER_EVT_SEEN)
 431                                 printk(KERN_WARNING "Carrier Event Seen\n");
 432                 }
 433                 rxb->status.raw=0;
 434                 priv->regs->rx_fifo=priv->rx_ring_dmas[priv->rx_write];
 435                 priv->rx_write=(priv->rx_write+1)&(RX_RING_ENTRIES-1);
 436                 if(priv->rx_write==twptr) {
 437                         DPRINTK("going rounds\n");
 438                 }
 439         }
 440         spin_unlock(&(priv->meth_lock));
 441 }
 442
 443 static int meth_tx_full(struct net_device *dev)
 444 {
 445         struct meth_private *priv = (struct meth_private *) dev->priv;
 446
 447         return(priv->tx_count >= TX_RING_ENTRIES-1);
 448 }
 449
 450 void meth_tx_cleanup(struct net_device* dev, int rptr)
 451 {
 452         meth_private *priv=dev->priv;
 453         tx_packet* status;
 454         struct sk_buff *skb;
 455
 456         spin_lock(&priv->meth_lock);
 457
 458         /* Stop DMA */
 459         priv->regs->dma_ctrl &= ~(METH_DMA_TX_INT_EN);
 460
 461         while(priv->tx_read != rptr){
 462                 skb = priv->tx_skbs[priv->tx_read];
 463                 status = &priv->tx_ring[priv->tx_read];
 464                 if(!status->header.res.sent)
 465                         break;
 466                 if(status->header.raw & METH_TX_STATUS_DONE) {
 467                         priv->stats.tx_packets++;
 468                         priv->stats.tx_bytes += skb->len;
 469                 }
 470                 dev_kfree_skb_irq(skb);
 471                 priv->tx_skbs[priv->tx_read] = NULL;
 472                 status->header.raw = 0;
 473                 priv->tx_read = (priv->tx_read+1)&(TX_RING_ENTRIES-1);
 474                 priv->tx_count --;
 475         }
 476
 477         /* wake up queue if it was stopped */
 478         if (netif_queue_stopped(dev) && ! meth_tx_full(dev)) {
 479                 netif_wake_queue(dev);
 480         }
 481
 482         spin_unlock(priv->meth_lock);
 483 }
 484
 485 /*
 486  * The typical interrupt entry point
 487  */
 488 irqreturn_t meth_interrupt(int irq, void *dev_id, struct pt_regs *pregs)
 489 {
 490         struct meth_private *priv;
 491         u32 status;
 492         /*
 493          * As usual, check the "device" pointer for shared handlers.
 494          * Then assign "struct device *dev"
 495          */
 496         struct net_device *dev = (struct net_device *)dev_id;
 497         /* ... and check with hw if it's really ours */
 498
 499         if (!dev /*paranoid*/ ) return IRQ_HANDLED;
 500
 501         priv = (struct meth_private *) dev->priv;
 502
 503         status = priv->regs->int_flags;
 504
 505         if (status & (METH_INT_RX_THRESHOLD|METH_INT_RX_UNDERFLOW)) {
 506                 /* send it to meth_rx for handling */
 507                 meth_rx(dev);
 508         }
 509
 510         if (status & (METH_INT_TX_EMPTY|METH_INT_TX_PKT)) {
 511                 /* a transmission is over: free the skb */
 512                 meth_tx_cleanup(dev, (priv->regs->tx_info&TX_INFO_RPTR)>>16);
 513         }
 514         /* check for errors too... */
 515         if (status & (METH_INT_TX_LINK_FAIL))
 516                 printk(KERN_WARNING "meth: link failure\n");
 517         if (status & (METH_INT_MEM_ERROR))
 518                 printk(KERN_WARNING "meth: memory error\n");
 519         if (status & (METH_INT_TX_ABORT))
 520                 printk(KERN_WARNING "meth: aborted\n");
 521         if (status & (METH_INT_RX_OVERFLOW))
 522                 printk(KERN_WARNING "meth: RX overflow\n");
 523         if (status & (METH_INT_RX_UNDERFLOW))
 524                 printk(KERN_WARNING "meth: RX underflow\n");
 525
 526 #define METH_INT_ERROR  (METH_INT_TX_LINK_FAIL| \
 527                         METH_INT_MEM_ERROR| \
 528                         METH_INT_TX_ABORT| \
 529                         METH_INT_RX_OVERFLOW| \
 530                         METH_INT_RX_UNDERFLOW)
 531         if( status & METH_INT_ERROR) {
 532                 printk(KERN_WARNING "meth: error status: 0x%08x\n",status);
 533                 netif_wake_queue(dev);
 534         }
 535         priv->regs->int_flags=status&0xff; /* clear interrupts */
 536         return IRQ_HANDLED;
 537 }
 538
 539 /*
 540  * Transmits packets that fit into TX descriptor (are <=120B)
 541  */
 542 static void meth_tx_short_prepare(meth_private* priv, struct sk_buff* skb)
 543 {
 544         tx_packet *desc=&priv->tx_ring[priv->tx_write];
 545         int len = (skb->len<ETH_ZLEN)?ETH_ZLEN:skb->len;
 546
 547         /* maybe I should set whole thing to 0 first... */
 548         memcpy(desc->data.dt+(120-len),skb->data,skb->len);
 549         if(skb->len < len)
 550                 memset(desc->data.dt+120-len+skb->len,0,len-skb->len);
 551         desc->header.raw=METH_TX_CMD_INT_EN|(len-1)|((128-len)<<16);
 552 }
 553 #define TX_CATBUF1 BIT(25)
 554 static void meth_tx_1page_prepare(meth_private* priv, struct sk_buff* skb)
 555 {
 556         tx_packet *desc=&priv->tx_ring[priv->tx_write];
 557         void *buffer_data = (void *)(((u64)skb->data + 7ULL) & (~7ULL));
 558         int unaligned_len = (int)((u64)buffer_data - (u64)skb->data);
 559         int buffer_len = skb->len - unaligned_len;
 560         dma_addr_t catbuf;
 561
 562         desc->header.raw=METH_TX_CMD_INT_EN|TX_CATBUF1|(skb->len-1);
 563
 564         /* unaligned part */
 565         if(unaligned_len){
 566                 memcpy(desc->data.dt+(120-unaligned_len),
 567                        skb->data, unaligned_len);
 568                 desc->header.raw |= (128-unaligned_len) << 16;
 569         }
 570
 571         /* first page */
 572         catbuf = dma_map_single(NULL, buffer_data, buffer_len,
 573                                 DMA_TO_DEVICE);
 574         desc->data.cat_buf[0].form.start_addr = catbuf >> 3;
 575         desc->data.cat_buf[0].form.len = buffer_len-1;
 576 }
 577 #define TX_CATBUF2 BIT(26)
 578 static void meth_tx_2page_prepare(meth_private* priv, struct sk_buff* skb)
 579 {
 580         tx_packet *desc=&priv->tx_ring[priv->tx_write];
 581         void *buffer1_data = (void *)(((u64)skb->data + 7ULL) & (~7ULL));
 582         void *buffer2_data = (void *)PAGE_ALIGN((u64)skb->data);
 583         int unaligned_len = (int)((u64)buffer1_data - (u64)skb->data);
 584         int buffer1_len = (int)((u64)buffer2_data - (u64)buffer1_data);
 585         int buffer2_len = skb->len - buffer1_len - unaligned_len;
 586         dma_addr_t catbuf1, catbuf2;
 587
 588         desc->header.raw=METH_TX_CMD_INT_EN|TX_CATBUF1|TX_CATBUF2|(skb->len-1);
 589         /* unaligned part */
 590         if(unaligned_len){
 591                 memcpy(desc->data.dt+(120-unaligned_len),
 592                        skb->data, unaligned_len);
 593                 desc->header.raw |= (128-unaligned_len) << 16;
 594         }
 595
 596         /* first page */
 597         catbuf1 = dma_map_single(NULL, buffer1_data, buffer1_len,
 598                                  DMA_TO_DEVICE);
 599         desc->data.cat_buf[0].form.start_addr = catbuf1 >> 3;
 600         desc->data.cat_buf[0].form.len = buffer1_len-1;
 601         /* second page */
 602         catbuf2 = dma_map_single(NULL, buffer2_data, buffer2_len,
 603                                  DMA_TO_DEVICE);
 604         desc->data.cat_buf[1].form.start_addr = catbuf2 >> 3;
 605         desc->data.cat_buf[1].form.len = buffer2_len-1;
 606 }
 607
 608 void meth_add_to_tx_ring(meth_private *priv, struct sk_buff* skb)
 609 {
 610         if(skb->len <= 120) {
 611                 /* Whole packet fits into descriptor */
 612                 meth_tx_short_prepare(priv,skb);
 613         } else if(PAGE_ALIGN((u64)skb->data) !=
 614                   PAGE_ALIGN((u64)skb->data+skb->len-1)) {
 615                 /* Packet crosses page boundary */
 616                 meth_tx_2page_prepare(priv,skb);
 617         } else {
 618                 /* Packet is in one page */
 619                 meth_tx_1page_prepare(priv,skb);
 620         }
 621
 622         /* Remember the skb, so we can free it at interrupt time */
 623         priv->tx_skbs[priv->tx_write] = skb;
 624         priv->tx_write = (priv->tx_write+1) & (TX_RING_ENTRIES-1);
 625         priv->regs->tx_info = priv->tx_write;
 626         priv->tx_count ++;
 627         /* Enable DMA transfer */
 628         priv->regs->dma_ctrl |= METH_DMA_TX_INT_EN;
 629 }
 630
 631 /*
 632  * Transmit a packet (called by the kernel)
 633  */
 634 int meth_tx(struct sk_buff *skb, struct net_device *dev)
 635 {
 636         struct meth_private *priv = (struct meth_private *) dev->priv;
 637
 638         spin_lock(&priv->meth_lock);
 639
 640         meth_add_to_tx_ring(priv, skb);
 641         dev->trans_start = jiffies; /* save the timestamp */
 642
 643         /* If TX ring is full, tell the upper layer to stop sending packets */
 644         if (meth_tx_full(dev)) {
 645                 printk("TX full: stopping\n");
 646                 netif_stop_queue(dev);
 647         }
 648
 649         spin_unlock(&priv->meth_lock);
 650
 651         return 0;
 652 }
 653
 654 /*
 655  * Deal with a transmit timeout.
 656  */
 657
 658 void meth_tx_timeout (struct net_device *dev)
 659 {
 660         struct meth_private *priv = (struct meth_private *) dev->priv;
 661
 662         printk(KERN_WARNING "%s: transmit timed out\n", dev->name);
 663
 664         /* Protect against concurrent rx interrupts */
 665         spin_lock(&priv->meth_lock);
 666
 667         /* Try to reset the interface. */
 668         meth_reset(dev);
 669
 670         priv->stats.tx_errors++;
 671
 672         /* Clear all rings */
 673         meth_free_tx_ring(priv);
 674         meth_free_rx_ring(priv);
 675         meth_init_tx_ring(priv);
 676         meth_init_rx_ring(priv);
 677
 678         /* Restart dma */
 679         priv->regs->dma_ctrl|=METH_DMA_TX_EN|METH_DMA_RX_EN|METH_DMA_RX_INT_EN;
 680
 681         /* Enable interrupt */
 682         spin_unlock(&priv->meth_lock);
 683
 684         dev->trans_start = jiffies;
 685         netif_wake_queue(dev);
 686
 687         return;
 688 }
 689
 690 /*
 691  * Ioctl commands
 692  */
 693 int meth_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 694 {
 695
 696         DPRINTK("ioctl\n");
 697         return 0;
 698 }
 699
 700 /*
 701  * Return statistics to the caller
 702  */
 703 struct net_device_stats *meth_stats(struct net_device *dev)
 704 {
 705         struct meth_private *priv = (struct meth_private *) dev->priv;
 706         return &priv->stats;
 707 }
 708
 709 /*
 710  * The init function (sometimes called probe).
 711  * It is invoked by register_netdev()
 712  */
 713 int meth_init(struct net_device *dev)
 714 {
 715         meth_private *priv=(meth_private*)dev->priv;
 716         /*
 717          * Then, assign other fields in dev, using ether_setup() and some
 718          * hand assignments
 719          */
 720         ether_setup(dev); /* assign some of the fields */
 721
 722         dev->open            = meth_open;
 723         dev->stop            = meth_release;
 724         dev->set_config      = meth_config;
 725         dev->hard_start_xmit = meth_tx;
 726         dev->do_ioctl        = meth_ioctl;
 727         dev->get_stats       = meth_stats;
 728 #ifdef HAVE_TX_TIMEOUT
 729         dev->tx_timeout      = meth_tx_timeout;
 730         dev->watchdog_timeo  = timeout;
 731 #endif
 732         dev->irq                 = MACE_ETHERNET_IRQ;
 733         SET_MODULE_OWNER(dev);
 734
 735         spin_lock_init(&((struct meth_private *) dev->priv)->meth_lock);
 736         /*
 737          * Make the usual checks: check_region(), probe irq, ...  -ENODEV
 738          * should be returned if no device found.  No resource should be
 739          * grabbed: this is done on open().
 740          */
 741         priv->regs=(meth_regs*)SGI_MFE;
 742         dev->base_addr=SGI_MFE;
 743         priv->phy_addr = -1; /* No phy is known yet... */
 744
 745         printk("SGI O2 Fast Ethernet rev. %ld\n", priv->regs->mac_ctrl >> 29);
 746
 747         return 0;
 748 }
 749
 750 /*
 751  * The devices
 752  */
 753
 754 struct net_device *meth_dev;
 755
 756 /*
 757  * Finally, the module stuff
 758  */
 759
 760 int meth_init_module(void)
 761 {
 762         int result, device_present = 0;
 763
 764         meth_dev=alloc_etherdev(sizeof(meth_private));
 765         meth_init(meth_dev);
 766
 767         if ( (result = register_netdev(meth_dev)) )
 768                 printk("meth: error %i registering device \"%s\"\n",
 769                        result, meth_dev->name);
 770         else device_present++;
 771
 772         return device_present ? 0 : -ENODEV;
 773 }
 774
 775 void meth_cleanup(void)
 776 {
 777         unregister_netdev(meth_dev);
 778         kfree(meth_dev);
 779         return;
 780 }
 781
 782 module_init(meth_init_module);
 783 module_exit(meth_cleanup);