drivers/net/de620.c

/* */
This source file includes following definitions.
de620_ready
de620_send_command
de620_put_byte
de620_read_byte
de620_write_block
de620_read_block
de620_set_delay
de620_set_register
de620_get_register
de620_open
de620_close
get_stats
de620_set_multicast_list
de620_start_xmit
de620_interrupt
de620_rx_intr
adapter_init
de620_probe
ReadAWord
read_eeprom
init_module
cleanup_module
   1 /*
   2  *      de620.c $Revision: 1.40 $ BETA
   3  *
   4  *
   5  *      Linux driver for the D-Link DE-620 Ethernet pocket adapter.
   6  *
   7  *      Portions (C) Copyright 1993, 1994 by Bjorn Ekwall <bj0rn@blox.se>
   8  *
   9  *      Based on adapter information gathered from DOS packetdriver
  10  *      sources from D-Link Inc:  (Special thanks to Henry Ngai of D-Link.)
  11  *              Portions (C) Copyright D-Link SYSTEM Inc. 1991, 1992
  12  *              Copyright, 1988, Russell Nelson, Crynwr Software
  13  *
  14  *      Adapted to the sample network driver core for linux,
  15  *      written by: Donald Becker <becker@super.org>
  16  *              (Now at <becker@cesdis.gsfc.nasa.gov>
  17  *
  18  *      Valuable assistance from:
  19  *              J. Joshua Kopper <kopper@rtsg.mot.com>
  20  *              Olav Kvittem <Olav.Kvittem@uninett.no>
  21  *              Germano Caronni <caronni@nessie.cs.id.ethz.ch>
  22  *              Jeremy Fitzhardinge <jeremy@suite.sw.oz.au>
  23  *
  24  *****************************************************************************/
  25 /*
  26  *      This program is free software; you can redistribute it and/or modify
  27  *      it under the terms of the GNU General Public License as published by
  28  *      the Free Software Foundation; either version 2, or (at your option)
  29  *      any later version.
  30  *
  31  *      This program is distributed in the hope that it will be useful,
  32  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  33  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  34  *      GNU General Public License for more details.
  35  *
  36  *      You should have received a copy of the GNU General Public License
  37  *      along with this program; if not, write to the Free Software
  38  *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 
  39  *
  40  *****************************************************************************/
  41 static const char *version =
  42         "de620.c: $Revision: 1.40 $,  Bjorn Ekwall <bj0rn@blox.se>\n";
  43 
  44 /***********************************************************************
  45  *
  46  * "Tuning" section.
  47  *
  48  * Compile-time options: (see below for descriptions)
  49  * -DDE620_IO=0x378     (lpt1)
  50  * -DDE620_IRQ=7        (lpt1)
  51  * -DDE602_DEBUG=...
  52  * -DSHUTDOWN_WHEN_LOST
  53  * -DCOUNT_LOOPS
  54  * -DLOWSPEED
  55  * -DREAD_DELAY
  56  * -DWRITE_DELAY
  57  */
  58 
  59 /*
  60  * This driver assumes that the printer port is a "normal",
  61  * dumb, uni-directional port!
  62  * If your port is "fancy" in any way, please try to set it to "normal"
  63  * with your BIOS setup.  I have no access to machines with bi-directional
  64  * ports, so I can't test such a driver :-(
  65  * (Yes, I _know_ it is possible to use DE620 with bidirectional ports...)
  66  *
  67  * There are some clones of DE620 out there, with different names.
  68  * If the current driver does not recognize a clone, try to change
  69  * the following #define to:
  70  *
  71  * #define DE620_CLONE 1
  72  */
  73 #define DE620_CLONE 0
  74 
  75 /*
  76  * If the adapter has problems with high speeds, enable this #define
  77  * otherwise full printerport speed will be attempted.
  78  *
  79  * You can tune the READ_DELAY/WRITE_DELAY below if you enable LOWSPEED
  80  *
  81 #define LOWSPEED
  82  */
  83 
  84 #ifndef READ_DELAY
  85 #define READ_DELAY 100  /* adapter internal read delay in 100ns units */
  86 #endif
  87 
  88 #ifndef WRITE_DELAY
  89 #define WRITE_DELAY 100 /* adapter internal write delay in 100ns units */
  90 #endif
  91 
  92 /*
  93  * Enable this #define if you want the adapter to do a "ifconfig down" on
  94  * itself when we have detected that something is possibly wrong with it.
  95  * The default behaviour is to retry with "adapter_init()" until success.
  96  * This should be used for debugging purposes only.
  97  *
  98 #define SHUTDOWN_WHEN_LOST
  99  */
 100 
 101 /*
 102  * Enable debugging by "-DDE620_DEBUG=3" when compiling,
 103  * OR in "./CONFIG"
 104  * OR by enabling the following #define
 105  *
 106  * use 0 for production, 1 for verification, >2 for debug
 107  *
 108 #define DE620_DEBUG 3
 109  */
 110 
 111 #ifdef LOWSPEED
 112 /*
 113  * Enable this #define if you want to see debugging output that show how long
 114  * we have to wait before the DE-620 is ready for the next read/write/command.
 115  *
 116 #define COUNT_LOOPS
 117  */
 118 #endif
 119 
 120 #include <linux/module.h>
 121 
 122 #include <linux/kernel.h>
 123 #include <linux/sched.h>
 124 #include <linux/types.h>
 125 #include <linux/fcntl.h>
 126 #include <linux/string.h>
 127 #include <linux/interrupt.h>
 128 #include <linux/ioport.h>
 129 #include <asm/io.h>
 130 #include <linux/in.h>
 131 #include <linux/ptrace.h>
 132 #include <asm/system.h>
 133 #include <linux/errno.h>
 134 
 135 #include <linux/inet.h>
 136 #include <linux/netdevice.h>
 137 #include <linux/etherdevice.h>
 138 #include <linux/skbuff.h>
 139 
 140 /* Constant definitions for the DE-620 registers, commands and bits */
 141 #include "de620.h"
 142 
 143 #define netstats enet_statistics
 144 typedef unsigned char byte;
 145 
 146 /*******************************************************
 147  *                                                     *
 148  * Definition of D-Link DE-620 Ethernet Pocket adapter *
 149  * See also "de620.h"                                  *
 150  *                                                     *
 151  *******************************************************/
 152 #ifndef DE620_IO /* Compile-time configurable */
 153 #define DE620_IO 0x378
 154 #endif
 155 
 156 #ifndef DE620_IRQ /* Compile-time configurable */
 157 #define DE620_IRQ       7
 158 #endif
 159 
 160 #define DATA_PORT       (dev->base_addr)
 161 #define STATUS_PORT     (dev->base_addr + 1)
 162 #define COMMAND_PORT    (dev->base_addr + 2)
 163 
 164 #define RUNT 60         /* Too small Ethernet packet */
 165 #define GIANT 1514      /* largest legal size packet, no fcs */
 166 
 167 #ifdef DE620_DEBUG /* Compile-time configurable */
 168 #define PRINTK(x) if (de620_debug >= 2) printk x
 169 #else
 170 #define DE620_DEBUG 0
 171 #define PRINTK(x) /**/
 172 #endif
 173 
 174 
 175 /*
 176  * Force media with insmod:
 177  *      insmod de620.o bnc=1
 178  * or
 179  *      insmod de620.o utp=1
 180  *
 181  * Force io and/or irq with insmod:
 182  *      insmod de620.o io=0x378 irq=7
 183  *
 184  * Make a clone skip the Ethernet-address range check:
 185  *      insmod de620.o clone=1
 186  */
 187 static int bnc = 0;
 188 static int utp = 0;
 189 static int io  = DE620_IO;
 190 static int irq = DE620_IRQ;
 191 static int clone = DE620_CLONE;
 192 
 193 static unsigned int de620_debug = DE620_DEBUG;
 194 
 195 /***********************************************
 196  *                                             *
 197  * Index to functions, as function prototypes. *
 198  *                                             *
 199  ***********************************************/
 200 
 201 /*
 202  * Routines used internally. (See also "convenience macros.. below")
 203  */
 204 
 205 /* Put in the device structure. */
 206 static int      de620_open(struct device *);
 207 static int      de620_close(struct device *);
 208 static struct netstats *get_stats(struct device *);
 209 static void     de620_set_multicast_list(struct device *);
 210 static int      de620_start_xmit(struct sk_buff *, struct device *);
 211 
 212 /* Dispatch from interrupts. */
 213 static void     de620_interrupt(int, struct pt_regs *);
 214 static int      de620_rx_intr(struct device *);
 215 
 216 /* Initialization */
 217 static int      adapter_init(struct device *);
 218 int             de620_probe(struct device *);
 219 static int      read_eeprom(struct device *);
 220 
 221 
 222 /*
 223  * D-Link driver variables:
 224  */
 225 #define SCR_DEF NIBBLEMODE |INTON | SLEEP | AUTOTX
 226 #define TCR_DEF RXPB                    /* not used: | TXSUCINT | T16INT */
 227 #define DE620_RX_START_PAGE 12          /* 12 pages (=3k) reserved for tx */
 228 #define DEF_NIC_CMD IRQEN | ICEN | DS1
 229 
 230 static volatile byte    NIC_Cmd;
 231 static volatile byte    next_rx_page;
 232 static byte             first_rx_page;
 233 static byte             last_rx_page;
 234 static byte             EIPRegister;
 235 
 236 static struct nic {
 237         byte    NodeID[6];
 238         byte    RAM_Size;
 239         byte    Model;
 240         byte    Media;
 241         byte    SCR;
 242 } nic_data;
 243 
 244 /**********************************************************
 245  *                                                        *
 246  * Convenience macros/functions for D-Link DE-620 adapter *
 247  *                                                        *
 248  **********************************************************/
 249 #define de620_tx_buffs(dd) (inb(STATUS_PORT) & (TXBF0 | TXBF1))
 250 #define de620_flip_ds(dd) NIC_Cmd ^= DS0 | DS1; outb(NIC_Cmd, COMMAND_PORT);
 251 
 252 /* Check for ready-status, and return a nibble (high 4 bits) for data input */
 253 #ifdef COUNT_LOOPS
 254 static int tot_cnt;
 255 #endif
 256 static inline byte
 257 de620_ready(struct device *dev)
     /*  */
 258 {
 259         byte value;
 260         register short int cnt = 0;
 261 
 262         while ((((value = inb(STATUS_PORT)) & READY) == 0) && (cnt <= 1000))
 263                 ++cnt;
 264 
 265 #ifdef COUNT_LOOPS
 266         tot_cnt += cnt;
 267 #endif
 268         return value & 0xf0; /* nibble */
 269 }
 270 
 271 static inline void
 272 de620_send_command(struct device *dev, byte cmd)
     /*  */
 273 {
 274         de620_ready(dev);
 275         if (cmd == W_DUMMY)
 276                 outb(NIC_Cmd, COMMAND_PORT);
 277 
 278         outb(cmd, DATA_PORT);
 279 
 280         outb(NIC_Cmd ^ CS0, COMMAND_PORT);
 281         de620_ready(dev);
 282         outb(NIC_Cmd, COMMAND_PORT);
 283 }
 284 
 285 static inline void
 286 de620_put_byte(struct device *dev, byte value)
     /*  */
 287 {
 288         /* The de620_ready() makes 7 loops, on the average, on a DX2/66 */
 289         de620_ready(dev);
 290         outb(value, DATA_PORT);
 291         de620_flip_ds(dev);
 292 }
 293 
 294 static inline byte
 295 de620_read_byte(struct device *dev)
     /*  */
 296 {
 297         byte value;
 298 
 299         /* The de620_ready() makes 7 loops, on the average, on a DX2/66 */
 300         value = de620_ready(dev); /* High nibble */
 301         de620_flip_ds(dev);
 302         value |= de620_ready(dev) >> 4; /* Low nibble */
 303         return value;
 304 }
 305 
 306 static inline void
 307 de620_write_block(struct device *dev, byte *buffer, int count)
     /*  */
 308 {
 309 #ifndef LOWSPEED
 310         byte uflip = NIC_Cmd ^ (DS0 | DS1);
 311         byte dflip = NIC_Cmd;
 312 #else /* LOWSPEED */
 313 #ifdef COUNT_LOOPS
 314         int bytes = count;
 315 #endif /* COUNT_LOOPS */
 316 #endif /* LOWSPEED */
 317 
 318 #ifdef LOWSPEED
 319 #ifdef COUNT_LOOPS
 320         tot_cnt = 0;
 321 #endif /* COUNT_LOOPS */
 322         /* No further optimization useful, the limit is in the adapter. */
 323         for ( ; count > 0; --count, ++buffer) {
 324                 de620_put_byte(dev,*buffer);
 325         }
 326         de620_send_command(dev,W_DUMMY);
 327 #ifdef COUNT_LOOPS
 328         /* trial debug output: loops per byte in de620_ready() */
 329         printk("WRITE(%d)\n", tot_cnt/((bytes?bytes:1)));
 330 #endif /* COUNT_LOOPS */
 331 #else /* not LOWSPEED */
 332         for ( ; count > 0; count -=2) {
 333                 outb(*buffer++, DATA_PORT);
 334                 outb(uflip, COMMAND_PORT);
 335                 outb(*buffer++, DATA_PORT);
 336                 outb(dflip, COMMAND_PORT);
 337         }
 338         de620_send_command(dev,W_DUMMY);
 339 #endif /* LOWSPEED */
 340 }
 341 
 342 static inline void
 343 de620_read_block(struct device *dev, byte *data, int count)
     /*  */
 344 {
 345 #ifndef LOWSPEED
 346         byte value;
 347         byte uflip = NIC_Cmd ^ (DS0 | DS1);
 348         byte dflip = NIC_Cmd;
 349 #else /* LOWSPEED */
 350 #ifdef COUNT_LOOPS
 351         int bytes = count;
 352 
 353         tot_cnt = 0;
 354 #endif /* COUNT_LOOPS */
 355 #endif /* LOWSPEED */
 356 
 357 #ifdef LOWSPEED
 358         /* No further optimization useful, the limit is in the adapter. */
 359         while (count-- > 0) {
 360                 *data++ = de620_read_byte(dev);
 361                 de620_flip_ds(dev);
 362         }
 363 #ifdef COUNT_LOOPS
 364         /* trial debug output: loops per byte in de620_ready() */
 365         printk("READ(%d)\n", tot_cnt/(2*(bytes?bytes:1)));
 366 #endif /* COUNT_LOOPS */
 367 #else /* not LOWSPEED */
 368         while (count-- > 0) {
 369                 value = inb(STATUS_PORT) & 0xf0; /* High nibble */
 370                 outb(uflip, COMMAND_PORT);
 371                 *data++ = value | inb(STATUS_PORT) >> 4; /* Low nibble */
 372                 outb(dflip , COMMAND_PORT);
 373         }
 374 #endif /* LOWSPEED */
 375 }
 376 
 377 static inline void
 378 de620_set_delay(struct device *dev)
     /*  */
 379 {
 380         de620_ready(dev);
 381         outb(W_DFR, DATA_PORT);
 382         outb(NIC_Cmd ^ CS0, COMMAND_PORT);
 383 
 384         de620_ready(dev);
 385 #ifdef LOWSPEED
 386         outb(WRITE_DELAY, DATA_PORT);
 387 #else
 388         outb(0, DATA_PORT);
 389 #endif
 390         de620_flip_ds(dev);
 391 
 392         de620_ready(dev);
 393 #ifdef LOWSPEED
 394         outb(READ_DELAY, DATA_PORT);
 395 #else
 396         outb(0, DATA_PORT);
 397 #endif
 398         de620_flip_ds(dev);
 399 }
 400 
 401 static inline void
 402 de620_set_register(struct device *dev, byte reg, byte value)
     /*  */
 403 {
 404         de620_ready(dev);
 405         outb(reg, DATA_PORT);
 406         outb(NIC_Cmd ^ CS0, COMMAND_PORT);
 407 
 408         de620_put_byte(dev, value);
 409 }
 410 
 411 static inline byte
 412 de620_get_register(struct device *dev, byte reg)
     /*  */
 413 {
 414         byte value;
 415 
 416         de620_send_command(dev,reg);
 417         value = de620_read_byte(dev);
 418         de620_send_command(dev,W_DUMMY);
 419 
 420         return value;
 421 }
 422 
 423 /*********************************************************************
 424  *
 425  * Open/initialize the board.
 426  *
 427  * This routine should set everything up anew at each open, even
 428  * registers that "should" only need to be set once at boot, so that
 429  * there is a non-reboot way to recover if something goes wrong.
 430  *
 431  */
 432 static int
 433 de620_open(struct device *dev)
     /*  */
 434 {
 435         if (request_irq(dev->irq, de620_interrupt, 0, "de620")) {
 436                 printk ("%s: unable to get IRQ %d\n", dev->name, dev->irq);
 437                 return 1;
 438         }
 439         irq2dev_map[dev->irq] = dev;
 440 
 441         MOD_INC_USE_COUNT;
 442         if (adapter_init(dev)) {
 443                 return 1;
 444         }
 445         dev->start = 1;
 446         return 0;
 447 }
 448 
 449 /************************************************
 450  *
 451  * The inverse routine to de620_open().
 452  *
 453  */
 454 static int
 455 de620_close(struct device *dev)
     /*  */
 456 {
 457         /* disable recv */
 458         de620_set_register(dev, W_TCR, RXOFF);
 459 
 460         free_irq(dev->irq);
 461         irq2dev_map[dev->irq] = NULL;
 462 
 463         dev->start = 0;
 464         MOD_DEC_USE_COUNT;
 465         return 0;
 466 }
 467 
 468 /*********************************************
 469  *
 470  * Return current statistics
 471  *
 472  */
 473 static struct netstats *
 474 get_stats(struct device *dev)
     /*  */
 475 {
 476         return (struct netstats *)(dev->priv);
 477 }
 478 
 479 /*********************************************
 480  *
 481  * Set or clear the multicast filter for this adaptor.
 482  * (no real multicast implemented for the DE-620, but she can be promiscuous...)
 483  *
 484  */
 485 
 486 static void de620_set_multicast_list(struct device *dev)
     /*  */
 487 {
 488         if (dev->mc_count || dev->flags&(IFF_ALLMULTI|IFF_PROMISC)) 
 489         { /* Enable promiscuous mode */
 490                 /*
 491                  *      We must make the kernel realise we had to move
 492                  *      into promisc mode or we start all out war on
 493                  *      the cable. - AC
 494                  */
 495                 dev->flags|=IFF_PROMISC;                
 496         
 497                 de620_set_register(dev, W_TCR, (TCR_DEF & ~RXPBM) | RXALL);
 498         }
 499         else 
 500         { /* Disable promiscuous mode, use normal mode */
 501                 de620_set_register(dev, W_TCR, TCR_DEF);
 502         }
 503 }
 504 
 505 /*******************************************************
 506  *
 507  * Copy a buffer to the adapter transmit page memory.
 508  * Start sending.
 509  */
 510 static int
 511 de620_start_xmit(struct sk_buff *skb, struct device *dev)
     /*  */
 512 {
 513         unsigned long flags;
 514         int len;
 515         int tickssofar;
 516         byte *buffer = skb->data;
 517         byte using_txbuf;
 518 
 519         /*
 520          * If some higher layer thinks we've missed a
 521          * tx-done interrupt we are passed NULL.
 522          * Caution: dev_tint() handles the cli()/sti() itself.
 523          */
 524 
 525         if (skb == NULL) {
 526                 dev_tint(dev);
 527                 return 0;
 528         }
 529 
 530         using_txbuf = de620_tx_buffs(dev); /* Peek at the adapter */
 531         dev->tbusy = (using_txbuf == (TXBF0 | TXBF1)); /* Boolean! */
 532 
 533         if (dev->tbusy) {       /* Do timeouts, to avoid hangs. */
 534                 tickssofar = jiffies - dev->trans_start;
 535 
 536                 if (tickssofar < 5)
 537                         return 1;
 538 
 539                 /* else */
 540                 printk("%s: transmit timed out (%d), %s?\n",
 541                         dev->name,
 542                         tickssofar,
 543                         "network cable problem"
 544                         );
 545                 /* Restart the adapter. */
 546                 if (adapter_init(dev)) /* maybe close it */
 547                         return 1;
 548         }
 549 
 550         if ((len = skb->len) < RUNT)
 551                 len = RUNT;
 552         if (len & 1) /* send an even number of bytes */
 553                 ++len;
 554 
 555         /* Start real output */
 556         save_flags(flags);
 557         cli();
 558 
 559         PRINTK(("de620_start_xmit: len=%d, bufs 0x%02x\n",
 560                 (int)skb->len, using_txbuf));
 561 
 562         /* select a free tx buffer. if there is one... */
 563         switch (using_txbuf) {
 564         default: /* both are free: use TXBF0 */
 565         case TXBF1: /* use TXBF0 */
 566                 de620_send_command(dev,W_CR | RW0);
 567                 using_txbuf |= TXBF0;
 568                 break;
 569 
 570         case TXBF0: /* use TXBF1 */
 571                 de620_send_command(dev,W_CR | RW1);
 572                 using_txbuf |= TXBF1;
 573                 break;
 574 
 575         case (TXBF0 | TXBF1): /* NONE!!! */
 576                 printk("de620: Ouch! No tx-buffer available!\n");
 577                 restore_flags(flags);
 578                 return 1;
 579                 break;
 580         }
 581         de620_write_block(dev, buffer, len);
 582 
 583         dev->trans_start = jiffies;
 584         dev->tbusy = (using_txbuf == (TXBF0 | TXBF1)); /* Boolean! */
 585 
 586         ((struct netstats *)(dev->priv))->tx_packets++;
 587         
 588         restore_flags(flags); /* interrupts maybe back on */
 589         
 590         dev_kfree_skb (skb, FREE_WRITE);
 591 
 592         return 0;
 593 }
 594 
 595 /*****************************************************
 596  *
 597  * Handle the network interface interrupts.
 598  *
 599  */
 600 static void
 601 de620_interrupt(int irq_in, struct pt_regs *regs)
     /*  */
 602 {
 603         struct device *dev = irq2dev_map[irq_in];
 604         byte irq_status;
 605         int bogus_count = 0;
 606         int again = 0;
 607 
 608         /* This might be deleted now, no crummy drivers present :-) Or..? */
 609         if ((dev == NULL) || (irq != irq_in)) {
 610                 printk("%s: bogus interrupt %d\n", dev?dev->name:"de620", irq_in);
 611                 return;
 612         }
 613 
 614         cli();
 615         dev->interrupt = 1;
 616 
 617         /* Read the status register (_not_ the status port) */
 618         irq_status = de620_get_register(dev, R_STS);
 619 
 620         PRINTK(("de620_interrupt (%2.2X)\n", irq_status));
 621 
 622         if (irq_status & RXGOOD) {
 623                 do {
 624                         again = de620_rx_intr(dev);
 625                         PRINTK(("again=%d\n", again));
 626                 }
 627                 while (again && (++bogus_count < 100));
 628         }
 629 
 630         dev->tbusy = (de620_tx_buffs(dev) == (TXBF0 | TXBF1)); /* Boolean! */
 631 
 632         dev->interrupt = 0;
 633         sti();
 634         return;
 635 }
 636 
 637 /**************************************
 638  *
 639  * Get a packet from the adapter
 640  *
 641  * Send it "upstairs"
 642  *
 643  */
 644 static int
 645 de620_rx_intr(struct device *dev)
     /*  */
 646 {
 647         struct header_buf {
 648                 byte            status;
 649                 byte            Rx_NextPage;
 650                 unsigned short  Rx_ByteCount;
 651         } header_buf;
 652         struct sk_buff *skb;
 653         int size;
 654         byte *buffer;
 655         byte pagelink;
 656         byte curr_page;
 657 
 658         PRINTK(("de620_rx_intr: next_rx_page = %d\n", next_rx_page));
 659 
 660         /* Tell the adapter that we are going to read data, and from where */
 661         de620_send_command(dev, W_CR | RRN);
 662         de620_set_register(dev, W_RSA1, next_rx_page);
 663         de620_set_register(dev, W_RSA0, 0);
 664 
 665         /* Deep breath, and away we goooooo */
 666         de620_read_block(dev, (byte *)&header_buf, sizeof(struct header_buf));
 667         PRINTK(("page status=0x%02x, nextpage=%d, packetsize=%d\n",
 668         header_buf.status, header_buf.Rx_NextPage, header_buf.Rx_ByteCount));
 669 
 670         /* Plausible page header? */
 671         pagelink = header_buf.Rx_NextPage;
 672         if ((pagelink < first_rx_page) || (last_rx_page < pagelink)) {
 673                 /* Ouch... Forget it! Skip all and start afresh... */
 674                 printk("%s: Ring overrun? Restoring...\n", dev->name);
 675                 /* You win some, you loose some. And sometimes plenty... */
 676                 adapter_init(dev);
 677                 ((struct netstats *)(dev->priv))->rx_over_errors++;
 678                 return 0;
 679         }
 680 
 681         /* OK, this look good, so far. Let's see if it's consistent... */
 682         /* Let's compute the start of the next packet, based on where we are */
 683         pagelink = next_rx_page +
 684                 ((header_buf.Rx_ByteCount + (4 - 1 + 0x100)) >> 8);
 685 
 686         /* Are we going to wrap around the page counter? */
 687         if (pagelink > last_rx_page)
 688                 pagelink -= (last_rx_page - first_rx_page + 1);
 689 
 690         /* Is the _computed_ next page number equal to what the adapter says? */
 691         if (pagelink != header_buf.Rx_NextPage) {
 692                 /* Naah, we'll skip this packet. Probably bogus data as well */
 693                 printk("%s: Page link out of sync! Restoring...\n", dev->name);
 694                 next_rx_page = header_buf.Rx_NextPage; /* at least a try... */
 695                 de620_send_command(dev, W_DUMMY);
 696                 de620_set_register(dev, W_NPRF, next_rx_page);
 697                 ((struct netstats *)(dev->priv))->rx_over_errors++;
 698                 return 0;
 699         }
 700         next_rx_page = pagelink;
 701 
 702         size = header_buf.Rx_ByteCount - 4;
 703         if ((size < RUNT) || (GIANT < size)) {
 704                 printk("%s: Illegal packet size: %d!\n", dev->name, size);
 705         }
 706         else { /* Good packet? */
 707                 skb = dev_alloc_skb(size+2);
 708                 if (skb == NULL) { /* Yeah, but no place to put it... */
 709                         printk("%s: Couldn't allocate a sk_buff of size %d.\n",
 710                                 dev->name, size);
 711                         ((struct netstats *)(dev->priv))->rx_dropped++;
 712                 }
 713                 else { /* Yep! Go get it! */
 714                         skb_reserve(skb,2);     /* Align */
 715                         skb->dev = dev;
 716                         skb->free = 1;
 717                         /* skb->data points to the start of sk_buff data area */
 718                         buffer = skb_put(skb,size);
 719                         /* copy the packet into the buffer */
 720                         de620_read_block(dev, buffer, size);
 721                         PRINTK(("Read %d bytes\n", size));
 722                         skb->protocol=eth_type_trans(skb,dev);
 723                         netif_rx(skb); /* deliver it "upstairs" */
 724                         /* count all receives */
 725                         ((struct netstats *)(dev->priv))->rx_packets++;
 726                 }
 727         }
 728 
 729         /* Let's peek ahead to see if we have read the last current packet */
 730         /* NOTE! We're _not_ checking the 'EMPTY'-flag! This seems better... */
 731         curr_page = de620_get_register(dev, R_CPR);
 732         de620_set_register(dev, W_NPRF, next_rx_page);
 733         PRINTK(("next_rx_page=%d CPR=%d\n", next_rx_page, curr_page));
 734 
 735         return (next_rx_page != curr_page); /* That was slightly tricky... */
 736 }
 737 
 738 /*********************************************
 739  *
 740  * Reset the adapter to a known state
 741  *
 742  */
 743 static int
 744 adapter_init(struct device *dev)
     /*  */
 745 {
 746         int i;
 747         static int was_down = 0;
 748 
 749         if ((nic_data.Model == 3) || (nic_data.Model == 0)) { /* CT */
 750                 EIPRegister = NCTL0;
 751                 if (nic_data.Media != 1)
 752                         EIPRegister |= NIS0;    /* not BNC */
 753         }
 754         else if (nic_data.Model == 2) { /* UTP */
 755                 EIPRegister = NCTL0 | NIS0;
 756         }
 757 
 758         if (utp)
 759                 EIPRegister = NCTL0 | NIS0;
 760         if (bnc)
 761                 EIPRegister = NCTL0;
 762 
 763         de620_send_command(dev, W_CR | RNOP | CLEAR);
 764         de620_send_command(dev, W_CR | RNOP);
 765 
 766         de620_set_register(dev, W_SCR, SCR_DEF);
 767         /* disable recv to wait init */
 768         de620_set_register(dev, W_TCR, RXOFF);
 769 
 770         /* Set the node ID in the adapter */
 771         for (i = 0; i < 6; ++i) { /* W_PARn = 0xaa + n */
 772                 de620_set_register(dev, W_PAR0 + i, dev->dev_addr[i]);
 773         }
 774 
 775         de620_set_register(dev, W_EIP, EIPRegister);
 776 
 777         next_rx_page = first_rx_page = DE620_RX_START_PAGE;
 778         if (nic_data.RAM_Size)
 779                 last_rx_page = nic_data.RAM_Size - 1;
 780         else /* 64k RAM */
 781                 last_rx_page = 255;
 782 
 783         de620_set_register(dev, W_SPR, first_rx_page); /* Start Page Register*/
 784         de620_set_register(dev, W_EPR, last_rx_page);  /* End Page Register */
 785         de620_set_register(dev, W_CPR, first_rx_page);/*Current Page Register*/
 786         de620_send_command(dev, W_NPR | first_rx_page); /* Next Page Register*/
 787         de620_send_command(dev, W_DUMMY);
 788         de620_set_delay(dev);
 789 
 790         /* Final sanity check: Anybody out there? */
 791         /* Let's hope some bits from the statusregister make a good check */
 792 #define CHECK_MASK (  0 | TXSUC |  T16  |  0  | RXCRC | RXSHORT |  0  |  0  )
 793 #define CHECK_OK   (  0 |   0   |  0    |  0  |   0   |   0     |  0  |  0  )
 794         /* success:   X     0      0       X      0       0        X     X  */
 795         /* ignore:   EEDI                RXGOOD                   COLS  LNKS*/
 796 
 797         if (((i = de620_get_register(dev, R_STS)) & CHECK_MASK) != CHECK_OK) {
 798                 printk("Something has happened to the DE-620!  Please check it"
 799 #ifdef SHUTDOWN_WHEN_LOST
 800                         " and do a new ifconfig"
 801 #endif
 802                         "! (%02x)\n", i);
 803 #ifdef SHUTDOWN_WHEN_LOST
 804                 /* Goodbye, cruel world... */
 805                 dev->flags &= ~IFF_UP;
 806                 de620_close(dev);
 807 #endif
 808                 was_down = 1;
 809                 return 1; /* failed */
 810         }
 811         if (was_down) {
 812                 printk("Thanks, I feel much better now!\n");
 813                 was_down = 0;
 814         }
 815 
 816         /* All OK, go ahead... */
 817         de620_set_register(dev, W_TCR, TCR_DEF);
 818 
 819         return 0; /* all ok */
 820 }
 821 
 822 /******************************************************************************
 823  *
 824  * Only start-up code below
 825  *
 826  */
 827 /****************************************
 828  *
 829  * Check if there is a DE-620 connected
 830  */
 831 int
 832 de620_probe(struct device *dev)
     /*  */
 833 {
 834         static struct netstats de620_netstats;
 835         int i;
 836         byte checkbyte = 0xa5;
 837 
 838         /*
 839          * This is where the base_addr and irq gets set.
 840          * Tunable at compile-time and insmod-time
 841          */
 842         dev->base_addr = io;
 843         dev->irq       = irq;
 844 
 845         if (de620_debug)
 846                 printk(version);
 847 
 848         printk("D-Link DE-620 pocket adapter");
 849 
 850         /* Initially, configure basic nibble mode, so we can read the EEPROM */
 851         NIC_Cmd = DEF_NIC_CMD;
 852         de620_set_register(dev, W_EIP, EIPRegister);
 853 
 854         /* Anybody out there? */
 855         de620_set_register(dev, W_CPR, checkbyte);
 856         checkbyte = de620_get_register(dev, R_CPR);
 857 
 858         if ((checkbyte != 0xa5) || (read_eeprom(dev) != 0)) {
 859                 printk(" not identified in the printer port\n");
 860                 return ENODEV;
 861         }
 862 
 863 #if 0 /* Not yet */
 864         if (check_region(dev->base_addr, 3)) {
 865                 printk(", port 0x%x busy\n", dev->base_addr);
 866                 return EBUSY;
 867         }
 868 #endif
 869         request_region(dev->base_addr, 3, "de620");
 870 
 871         /* else, got it! */
 872         printk(", Ethernet Address: %2.2X",
 873                 dev->dev_addr[0] = nic_data.NodeID[0]);
 874         for (i = 1; i < ETH_ALEN; i++) {
 875                 printk(":%2.2X", dev->dev_addr[i] = nic_data.NodeID[i]);
 876                 dev->broadcast[i] = 0xff;
 877         }
 878 
 879         printk(" (%dk RAM,",
 880                 (nic_data.RAM_Size) ? (nic_data.RAM_Size >> 2) : 64);
 881 
 882         if (nic_data.Media == 1)
 883                 printk(" BNC)\n");
 884         else
 885                 printk(" UTP)\n");
 886 
 887         /* Initialize the device structure. */
 888         /*dev->priv = kmalloc(sizeof(struct netstats), GFP_KERNEL);*/
 889         dev->priv = &de620_netstats;
 890 
 891         memset(dev->priv, 0, sizeof(struct netstats));
 892         dev->get_stats = get_stats;
 893         dev->open = de620_open;
 894         dev->stop = de620_close;
 895         dev->hard_start_xmit = &de620_start_xmit;
 896         dev->set_multicast_list = &de620_set_multicast_list;
 897         /* base_addr and irq are already set, see above! */
 898 
 899         ether_setup(dev);
 900         
 901         /* dump eeprom */
 902         if (de620_debug) {
 903                 printk("\nEEPROM contents:\n");
 904                 printk("RAM_Size = 0x%02X\n", nic_data.RAM_Size);
 905                 printk("NodeID = %02X:%02X:%02X:%02X:%02X:%02X\n",
 906                         nic_data.NodeID[0], nic_data.NodeID[1],
 907                         nic_data.NodeID[2], nic_data.NodeID[3],
 908                         nic_data.NodeID[4], nic_data.NodeID[5]);
 909                 printk("Model = %d\n", nic_data.Model);
 910                 printk("Media = %d\n", nic_data.Media);
 911                 printk("SCR = 0x%02x\n", nic_data.SCR);
 912         }
 913 
 914         return 0;
 915 }
 916 
 917 /**********************************
 918  *
 919  * Read info from on-board EEPROM
 920  *
 921  * Note: Bitwise serial I/O to/from the EEPROM vi the status _register_!
 922  */
 923 #define sendit(dev,data) de620_set_register(dev, W_EIP, data | EIPRegister);
 924 
 925 static unsigned short
 926 ReadAWord(struct device *dev, int from)
     /*  */
 927 {
 928         unsigned short data;
 929         int nbits;
 930 
 931         /* cs   [__~~] SET SEND STATE */
 932         /* di   [____]                */
 933         /* sck  [_~~_]                */
 934         sendit(dev, 0); sendit(dev, 1); sendit(dev, 5); sendit(dev, 4);
 935 
 936         /* Send the 9-bit address from where we want to read the 16-bit word */
 937         for (nbits = 9; nbits > 0; --nbits, from <<= 1) {
 938                 if (from & 0x0100) { /* bit set? */
 939                         /* cs    [~~~~] SEND 1 */
 940                         /* di    [~~~~]        */
 941                         /* sck   [_~~_]        */
 942                         sendit(dev, 6); sendit(dev, 7); sendit(dev, 7); sendit(dev, 6);
 943                 }
 944                 else {
 945                         /* cs    [~~~~] SEND 0 */
 946                         /* di    [____]        */
 947                         /* sck   [_~~_]        */
 948                         sendit(dev, 4); sendit(dev, 5); sendit(dev, 5); sendit(dev, 4);
 949                 }
 950         }
 951 
 952         /* Shift in the 16-bit word. The bits appear serially in EEDI (=0x80) */
 953         for (data = 0, nbits = 16; nbits > 0; --nbits) {
 954                 /* cs    [~~~~] SEND 0 */
 955                 /* di    [____]        */
 956                 /* sck   [_~~_]        */
 957                 sendit(dev, 4); sendit(dev, 5); sendit(dev, 5); sendit(dev, 4);
 958                 data = (data << 1) | ((de620_get_register(dev, R_STS) & EEDI) >> 7);
 959         }
 960         /* cs    [____] RESET SEND STATE */
 961         /* di    [____]                  */
 962         /* sck   [_~~_]                  */
 963         sendit(dev, 0); sendit(dev, 1); sendit(dev, 1); sendit(dev, 0);
 964 
 965         return data;
 966 }
 967 
 968 static int
 969 read_eeprom(struct device *dev)
     /*  */
 970 {
 971         unsigned short wrd;
 972 
 973         /* D-Link Ethernet addresses are in the series  00:80:c8:7X:XX:XX:XX */
 974         wrd = ReadAWord(dev, 0x1aa);    /* bytes 0 + 1 of NodeID */
 975         if (!clone && (wrd != htons(0x0080))) /* Valid D-Link ether sequence? */
 976                 return -1; /* Nope, not a DE-620 */
 977         nic_data.NodeID[0] = wrd & 0xff;
 978         nic_data.NodeID[1] = wrd >> 8;
 979 
 980         wrd = ReadAWord(dev, 0x1ab);    /* bytes 2 + 3 of NodeID */
 981         if (!clone && ((wrd & 0xff) != 0xc8)) /* Valid D-Link ether sequence? */
 982                 return -1; /* Nope, not a DE-620 */
 983         nic_data.NodeID[2] = wrd & 0xff;
 984         nic_data.NodeID[3] = wrd >> 8;
 985 
 986         wrd = ReadAWord(dev, 0x1ac);    /* bytes 4 + 5 of NodeID */
 987         nic_data.NodeID[4] = wrd & 0xff;
 988         nic_data.NodeID[5] = wrd >> 8;
 989 
 990         wrd = ReadAWord(dev, 0x1ad);    /* RAM size in pages (256 bytes). 0 = 64k */
 991         nic_data.RAM_Size = (wrd >> 8);
 992 
 993         wrd = ReadAWord(dev, 0x1ae);    /* hardware model (CT = 3) */
 994         nic_data.Model = (wrd & 0xff);
 995 
 996         wrd = ReadAWord(dev, 0x1af); /* media (indicates BNC/UTP) */
 997         nic_data.Media = (wrd & 0xff);
 998 
 999         wrd = ReadAWord(dev, 0x1a8); /* System Configuration Register */
1000         nic_data.SCR = (wrd >> 8);
1001 
1002         return 0; /* no errors */
1003 }
1004 
1005 /******************************************************************************
1006  *
1007  * Loadable module skeleton
1008  *
1009  */
1010 #ifdef MODULE
1011 static char nullname[8] = "";
1012 static struct device de620_dev = {
1013         nullname, 0, 0, 0, 0, 0, 0, 0, 0, 0, NULL, de620_probe };
1014 
1015 int
1016 init_module(void)
     /*  */
1017 {
1018         if (register_netdev(&de620_dev) != 0)
1019                 return -EIO;
1020         return 0;
1021 }
1022 
1023 void
1024 cleanup_module(void)
     /*  */
1025 {
1026         unregister_netdev(&de620_dev);
1027         release_region(de620_dev.base_addr, 3);
1028 }
1029 #endif /* MODULE */
1030 
1031 /*
1032  * (add '-DMODULE' when compiling as loadable module)
1033  *
1034  * compile-command:
1035  *      gcc -D__KERNEL__ -Wall -Wstrict-prototypes -O2 \
1036  *       -fomit-frame-pointer -m486 \
1037  *      -I/usr/src/linux/include -I../../net/inet -c de620.c
1038 */
1039 /*
1040  * Local variables:
1041  *  kernel-compile-command: "gcc -D__KERNEL__ -Ilinux/include -I../../net/inet -Wall -Wstrict-prototypes -O2 -m486 -c de620.c"
1042  *  module-compile-command: "gcc -D__KERNEL__ -DMODULE -Ilinux/include -I../../net/inet -Wall -Wstrict-prototypes -O2 -m486 -c de620.c"
1043  *  compile-command: "gcc -D__KERNEL__ -DMODULE -Ilinux/include -I../../net/inet -Wall -Wstrict-prototypes -O2 -m486 -c de620.c"
1044  * End:
1045  */
/* */
root/drivers/net/de620.c

DEFINITIONS
