root/drivers/net/atp.c

/* [previous][next][first][last][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. atp_init
  2. atp_probe1
  3. get_node_ID
  4. eeprom_op
  5. net_open
  6. hardware_init
  7. trigger_send
  8. write_packet
  9. net_send_packet
  10. net_interrupt
  11. net_rx
  12. read_block
  13. net_close
  14. net_get_stats
  15. set_multicast_list

   1 /* atp.c: Attached (pocket) ethernet adaptor driver for linux. */
   2 /*
   3         Written 1993 by Donald Becker.
   4         Copyright 1993 United States Government as represented by the Director,
   5         National Security Agency.  This software may only be used and distributed
   6         according to the terms of the GNU Public License as modified by SRC,
   7         incorporated herein by reference.
   8 
   9         The author may be reached as becker@super.org or
  10         C/O Supercomputing Research Ctr., 17100 Science Dr., Bowie MD 20715
  11 
  12 */
  13 
  14 static char *version =
  15         "atp.c:v0.04 2/25/94 Donald Becker (becker@super.org)\n";
  16 
  17 /*
  18         This file is a device driver for the RealTek (aka AT-Lan-Tec) pocket
  19         ethernet adaptor.  This is a common low-cost OEM pocket ethernet
  20         adaptor, sold under many names.
  21 
  22   Sources:
  23         This driver was written from the packet driver assembly code provided by
  24         Vincent Bono of AT-Lan-Tec.      Ever try to figure out how a complicated
  25         device works just from the assembly code?  It ain't pretty.  The following
  26         description is written based on guesses and writing lots of special-purpose
  27         code to test my theorized operation.
  28 
  29                                         Theory of Operation
  30         
  31         The RTL8002 adaptor seems to be built around a custom spin of the SEEQ
  32         controller core.  It probably has a 16K or 64K internal packet buffer, of
  33         which the first 4K is devoted to transmit and the rest to receive.
  34         The controller maintains the queue of received packet and the packet buffer
  35         access pointer internally, with only 'reset to beginning' and 'skip to next
  36         packet' commands visible.  The transmit packet queue holds two (or more?)
  37         packets: both 'retransmit this packet' (due to collision) and 'transmit next
  38         packet' commands must be started by hand.
  39 
  40         The station address is stored in a standard bit-serial EEPROM which must be
  41         read (ughh) by the device driver.  (Provisions have been made for
  42         substituting a 74S288 PROM, but I haven't gotten reports of any models
  43         using it.)  Unlike built-in devices, a pocket adaptor can temporarily lose
  44         power without indication to the device driver.  The major effect is that
  45         the station address, receive filter (promiscuous, etc.) and transceiver
  46         must be reset.
  47 
  48         The controller itself has 16 registers, some of which use only the lower
  49         bits.  The registers are read and written 4 bits at a time.  The four bit
  50         register address is presented on the data lines along with a few additional
  51         timing and control bits.  The data is then read from status port or written
  52         to the data port.
  53 
  54         Since the bulk data transfer of the actual packets through the slow
  55         parallel port dominates the driver's running time, four distinct data
  56         (non-register) transfer modes are provided by the adaptor, two in each
  57         direction.  In the first mode timing for the nibble transfers is
  58         provided through the data port.  In the second mode the same timing is
  59         provided through the control port.  In either case the data is read from
  60         the status port and written to the data port, just as it is accessing
  61         registers.
  62 
  63         In addition to the basic data transfer methods, several more are modes are
  64         created by adding some delay by doing multiple reads of the data to allow
  65         it to stabilize.  This delay seems to be needed on most machines.
  66 
  67         The data transfer mode is stored in the 'dev->if_port' field.  Its default
  68         value is '4'.  It may be overridden at boot-time using the third parameter
  69         to the "ether=..." initialization.
  70 
  71         The header file <atp.h> provides inline functions that encapsulate the
  72         register and data access methods.  These functions are hand-tuned to
  73         generate reasonable object code.  This header file also documents my
  74         interpretations of the device registers.
  75 */
  76 
  77 #include <linux/config.h>               /* Used only to override default values. */
  78 #include <linux/kernel.h>
  79 #include <linux/sched.h>
  80 #include <linux/types.h>
  81 #include <linux/fcntl.h>
  82 #include <linux/interrupt.h>
  83 #include <linux/ptrace.h>
  84 #include <linux/ioport.h>
  85 #include <linux/in.h>
  86 #include <linux/malloc.h>
  87 #include <linux/string.h>
  88 #include <asm/system.h>
  89 #include <asm/bitops.h>
  90 #include <asm/io.h>
  91 #include <asm/dma.h>
  92 #include <errno.h>
  93 
  94 #include <linux/netdevice.h>
  95 #include <linux/etherdevice.h>
  96 #include <linux/skbuff.h>
  97 
  98 #include "atp.h"
  99 
 100 /* Compatibility definitions for earlier kernel versions. */
 101 #ifndef HAVE_AUTOIRQ
 102 /* From auto_irq.c, in ioport.h for later versions. */
 103 extern void autoirq_setup(int waittime);
 104 extern int autoirq_report(int waittime);
 105 /* The map from IRQ number (as passed to the interrupt handler) to
 106    'struct device'. */
 107 extern struct device *irq2dev_map[16];
 108 #endif
 109 
 110 #ifndef HAVE_ALLOC_SKB
 111 #define alloc_skb(size, priority) (struct sk_buff *) kmalloc(size,priority)
 112 #define kfree_skbmem(addr, size) kfree_s(addr,size);
 113 #endif
 114 
 115 #ifndef HAVE_PORTRESERVE
 116 #define check_region(ioaddr, size)              0
 117 #define snarf_region(ioaddr, size);             do ; while (0)
 118 #endif
 119 
 120 /* use 0 for production, 1 for verification, >2 for debug */
 121 #ifndef NET_DEBUG
 122 #define NET_DEBUG 4
 123 #endif
 124 static unsigned int net_debug = NET_DEBUG;
 125 
 126 /* The number of low I/O ports used by the ethercard. */
 127 #define ETHERCARD_TOTAL_SIZE    3
 128 
 129 /* Index to functions, as function prototypes. */
 130 
 131 extern int atp_probe(struct device *dev);
 132 
 133 static int atp_probe1(struct device *dev, short ioaddr);
 134 static void get_node_ID(struct device *dev);
 135 static unsigned short eeprom_op(short ioaddr, unsigned int cmd);
 136 static int net_open(struct device *dev);
 137 static void hardware_init(struct device *dev);
 138 static void write_packet(short ioaddr, int length, unsigned char *packet, int mode);
 139 static void trigger_send(short ioaddr, int length);
 140 static int      net_send_packet(struct sk_buff *skb, struct device *dev);
 141 static void net_interrupt(int reg_ptr);
 142 static void net_rx(struct device *dev);
 143 static void read_block(short ioaddr, int length, unsigned char *buffer, int data_mode);
 144 static int net_close(struct device *dev);
 145 static struct enet_statistics *net_get_stats(struct device *dev);
 146 static void set_multicast_list(struct device *dev, int num_addrs, void *addrs);
 147 
 148 
 149 /* Check for a network adaptor of this type, and return '0' iff one exists.
 150    If dev->base_addr == 0, probe all likely locations.
 151    If dev->base_addr == 1, always return failure.
 152    If dev->base_addr == 2, allocate space for the device and return success
 153    (detachable devices only).
 154    */
 155 int
 156 atp_init(struct device *dev)
     /* [previous][next][first][last][top][bottom][index][help] */
 157 {
 158         int *port, ports[] = {0x378, 0x278, 0x3bc, 0};
 159         int base_addr = dev->base_addr;
 160 
 161         if (base_addr > 0x1ff)          /* Check a single specified location. */
 162                 return atp_probe1(dev, base_addr);
 163         else if (base_addr == 1)        /* Don't probe at all. */
 164                 return ENXIO;
 165 
 166         for (port = ports; *port; port++) {
 167                 int ioaddr = *port;
 168                 outb(0x57, ioaddr + PAR_DATA);
 169                 if (inb(ioaddr + PAR_DATA) != 0x57)
 170                         continue;
 171                 if (atp_probe1(dev, ioaddr) == 0)
 172                         return 0;
 173         }
 174 
 175         return ENODEV;
 176 }
 177 
 178 static int atp_probe1(struct device *dev, short ioaddr)
     /* [previous][next][first][last][top][bottom][index][help] */
 179 {
 180         int saved_ctrl_reg, status;
 181 
 182         outb(0xff, ioaddr + PAR_DATA);
 183         /* Save the original value of the Control register, in case we guessed
 184            wrong. */
 185         saved_ctrl_reg = inb(ioaddr + PAR_CONTROL);
 186         /* IRQEN=0, SLCTB=high INITB=high, AUTOFDB=high, STBB=high. */
 187         outb(0x04, ioaddr + PAR_CONTROL);
 188         write_reg_high(ioaddr, CMR1, CMR1h_RESET);
 189         eeprom_delay(2048);
 190         status = read_nibble(ioaddr, CMR1);
 191 
 192         if ((status & 0x78) != 0x08) {
 193                 /* The pocket adaptor probe failed, restore the control register. */
 194                 outb(saved_ctrl_reg, ioaddr + PAR_CONTROL);
 195                 return 1;
 196         }
 197         status = read_nibble(ioaddr, CMR2_h);
 198         if ((status & 0x78) != 0x10) {
 199                 outb(saved_ctrl_reg, ioaddr + PAR_CONTROL);
 200                 return 1;
 201         }
 202         /* Find the IRQ used by triggering an interrupt. */
 203         write_reg_byte(ioaddr, CMR2, 0x01);                     /* No accept mode, IRQ out. */
 204         write_reg_high(ioaddr, CMR1, CMR1h_RxENABLE | CMR1h_TxENABLE);  /* Enable Tx and Rx. */
 205 
 206         /* Omit autoIRQ routine for now. Use "table lookup" instead.  Uhgggh. */
 207         if (ioaddr == 0x378)
 208                 dev->irq = 7;
 209         else
 210                 dev->irq = 5;
 211         write_reg_high(ioaddr, CMR1, CMR1h_TxRxOFF); /* Disable Tx and Rx units. */
 212         write_reg(ioaddr, CMR2, CMR2_NULL);
 213 
 214         dev->base_addr = ioaddr;
 215 
 216         /* Read the station address PROM.  */
 217         get_node_ID(dev);
 218 
 219         printk("%s: Pocket adaptor found at %#3x, IRQ %d, SAPROM "
 220                    "%02X:%02X:%02X:%02X:%02X:%02X.\n", dev->name, dev->base_addr,
 221                    dev->irq, dev->dev_addr[0], dev->dev_addr[1], dev->dev_addr[2],
 222                    dev->dev_addr[3], dev->dev_addr[4], dev->dev_addr[5]);
 223 
 224         /* Leave the hardware in a reset state. */
 225     write_reg_high(ioaddr, CMR1, CMR1h_RESET);
 226 
 227         if (net_debug)
 228                 printk(version);
 229 
 230         /* Initialize the device structure. */
 231         ether_setup(dev);
 232         dev->priv = kmalloc(sizeof(struct net_local), GFP_KERNEL);
 233         memset(dev->priv, 0, sizeof(struct net_local));
 234 
 235 
 236         {
 237                 struct net_local *lp = (struct net_local *)dev->priv;
 238                 lp->addr_mode = CMR2h_Normal;
 239         }
 240 
 241         /* For the ATP adaptor the "if_port" is really the data transfer mode. */
 242         dev->if_port = (dev->mem_start & 0xf) ? dev->mem_start & 0x7 : 4;
 243         if (dev->mem_end & 0xf)
 244                 net_debug = dev->mem_end & 7;
 245 
 246         dev->open               = net_open;
 247         dev->stop               = net_close;
 248         dev->hard_start_xmit = net_send_packet;
 249         dev->get_stats  = net_get_stats;
 250         dev->set_multicast_list = &set_multicast_list;
 251 
 252         return 0;
 253 }
 254 
 255 /* Read the station address PROM, usually a word-wide EEPROM. */
 256 static void get_node_ID(struct device *dev)
     /* [previous][next][first][last][top][bottom][index][help] */
 257 {
 258         short ioaddr = dev->base_addr;
 259         int sa_offset = 0;
 260         int i;
 261         
 262         write_reg(ioaddr, CMR2, CMR2_EEPROM);     /* Point to the EEPROM control registers. */
 263         
 264         /* Some adaptors have the station address at offset 15 instead of offset
 265            zero.  Check for it, and fix it if needed. */
 266         if (eeprom_op(ioaddr, EE_READ(0)) == 0xffff)
 267                 sa_offset = 15;
 268         
 269         for (i = 0; i < 3; i++)
 270                 ((unsigned short *)dev->dev_addr)[i] =
 271                         ntohs(eeprom_op(ioaddr, EE_READ(sa_offset + i)));
 272         
 273         write_reg(ioaddr, CMR2, CMR2_NULL);
 274 }
 275 
 276 /*
 277   An EEPROM read command starts by shifting out 0x60+address, and then
 278   shifting in the serial data. See the NatSemi databook for details.
 279  *                 ________________
 280  * CS : __|
 281  *                         ___     ___
 282  * CLK: ______|   |___|   |
 283  *               __ _______ _______
 284  * DI :  __X_______X_______X
 285  * DO :  _________X_______X
 286  */
 287 
 288 static unsigned short eeprom_op(short ioaddr, unsigned int cmd)
     /* [previous][next][first][last][top][bottom][index][help] */
 289 {
 290         unsigned eedata_out = 0;
 291         int num_bits = EE_CMD_SIZE;
 292         
 293         while (--num_bits >= 0) {
 294                 char outval = test_bit(num_bits, &cmd) ? EE_DATA_WRITE : 0;
 295                 write_reg_high(ioaddr, PROM_CMD, outval | EE_CLK_LOW);
 296                 eeprom_delay(5);
 297                 write_reg_high(ioaddr, PROM_CMD, outval | EE_CLK_HIGH);
 298                 eedata_out <<= 1;
 299                 if (read_nibble(ioaddr, PROM_DATA) & EE_DATA_READ)
 300                         eedata_out++;
 301                 eeprom_delay(5);
 302         }
 303         write_reg_high(ioaddr, PROM_CMD, EE_CLK_LOW & ~EE_CS);
 304         return eedata_out;
 305 }
 306 
 307 
 308 /* Open/initialize the board.  This is called (in the current kernel)
 309    sometime after booting when the 'ifconfig' program is run.
 310 
 311    This routine sets everything up anew at each open, even
 312    registers that "should" only need to be set once at boot, so that
 313    there is non-reboot way to recover if something goes wrong.
 314 
 315    This is an attachable device: if there is no dev->priv entry then it wasn't
 316    probed for at boot-time, and we need to probe for it again.
 317    */
 318 static int net_open(struct device *dev)
     /* [previous][next][first][last][top][bottom][index][help] */
 319 {
 320 
 321         /* The interrupt line is turned off (tri-stated) when the device isn't in
 322            use.  That's especially important for "attached" interfaces where the
 323            port or interrupt may be shared. */
 324         if (irq2dev_map[dev->irq] != 0
 325                 || (irq2dev_map[dev->irq] = dev) == 0
 326                 || request_irq(dev->irq, &net_interrupt, 0, "atp")) {
 327                 return -EAGAIN;
 328         }
 329 
 330         hardware_init(dev);
 331         dev->start = 1;
 332         return 0;
 333 }
 334 
 335 /* This routine resets the hardware.  We initialize everything, assuming that
 336    the hardware may have been temporarily detached. */
 337 static void hardware_init(struct device *dev)
     /* [previous][next][first][last][top][bottom][index][help] */
 338 {
 339         struct net_local *lp = (struct net_local *)dev->priv;
 340         int ioaddr = dev->base_addr;
 341     int i;
 342 
 343         write_reg_high(ioaddr, CMR1, CMR1h_RESET);
 344         
 345     for (i = 0; i < 6; i++)
 346                 write_reg_byte(ioaddr, PAR0 + i, dev->dev_addr[i]);
 347 
 348         write_reg_high(ioaddr, CMR2, lp->addr_mode);
 349 
 350         if (net_debug > 2) {
 351                 printk("%s: Reset: current Rx mode %d.\n", dev->name,
 352                            (read_nibble(ioaddr, CMR2_h) >> 3) & 0x0f);
 353         }
 354 
 355     write_reg(ioaddr, CMR2, CMR2_IRQOUT);
 356     write_reg_high(ioaddr, CMR1, CMR1h_RxENABLE | CMR1h_TxENABLE);
 357 
 358         /* Enable the interrupt line from the serial port. */
 359         outb(Ctrl_SelData + Ctrl_IRQEN, ioaddr + PAR_CONTROL);
 360 
 361         /* Unmask the interesting interrupts. */
 362     write_reg(ioaddr, IMR, ISR_RxOK | ISR_TxErr | ISR_TxOK);
 363     write_reg_high(ioaddr, IMR, ISRh_RxErr);
 364 
 365         lp->tx_unit_busy = 0;
 366     lp->pac_cnt_in_tx_buf = 0;
 367         lp->saved_tx_size = 0;
 368 
 369         dev->tbusy = 0;
 370         dev->interrupt = 0;
 371 }
 372 
 373 static void trigger_send(short ioaddr, int length)
     /* [previous][next][first][last][top][bottom][index][help] */
 374 {
 375         write_reg_byte(ioaddr, TxCNT0, length & 0xff);
 376         write_reg(ioaddr, TxCNT1, length >> 8);
 377         write_reg(ioaddr, CMR1, CMR1_Xmit);
 378 }
 379 
 380 static void write_packet(short ioaddr, int length, unsigned char *packet, int data_mode)
     /* [previous][next][first][last][top][bottom][index][help] */
 381 {
 382     length = (length + 1) & ~1;         /* Round up to word length. */
 383     outb(EOC+MAR, ioaddr + PAR_DATA);
 384     if ((data_mode & 1) == 0) {
 385                 /* Write the packet out, starting with the write addr. */
 386                 outb(WrAddr+MAR, ioaddr + PAR_DATA);
 387                 do {
 388                         write_byte_mode0(ioaddr, *packet++);
 389                 } while (--length > 0) ;
 390     } else {
 391                 /* Write the packet out in slow mode. */
 392                 unsigned char outbyte = *packet++;
 393 
 394                 outb(Ctrl_LNibWrite + Ctrl_IRQEN, ioaddr + PAR_CONTROL);
 395                 outb(WrAddr+MAR, ioaddr + PAR_DATA);
 396 
 397                 outb((outbyte & 0x0f)|0x40, ioaddr + PAR_DATA);
 398                 outb(outbyte & 0x0f, ioaddr + PAR_DATA);
 399                 outbyte >>= 4;
 400                 outb(outbyte & 0x0f, ioaddr + PAR_DATA);
 401                 outb(Ctrl_HNibWrite + Ctrl_IRQEN, ioaddr + PAR_CONTROL);
 402                 while (--length > 0)
 403                         write_byte_mode1(ioaddr, *packet++);
 404     }
 405     /* Terminate the Tx frame.  End of write: ECB. */
 406     outb(0xff, ioaddr + PAR_DATA);
 407     outb(Ctrl_HNibWrite | Ctrl_SelData | Ctrl_IRQEN, ioaddr + PAR_CONTROL);
 408 }
 409 
 410 static int
 411 net_send_packet(struct sk_buff *skb, struct device *dev)
     /* [previous][next][first][last][top][bottom][index][help] */
 412 {
 413         struct net_local *lp = (struct net_local *)dev->priv;
 414         int ioaddr = dev->base_addr;
 415 
 416         if (dev->tbusy) {
 417                 /* If we get here, some higher level has decided we are broken.
 418                    There should really be a "kick me" function call instead. */
 419                 int tickssofar = jiffies - dev->trans_start;
 420                 if (tickssofar < 5)
 421                         return 1;
 422                 printk("%s: transmit timed out, %s?\n", dev->name,
 423                            inb(ioaddr + PAR_CONTROL) & 0x10 ? "network cable problem"
 424                            :  "IRQ conflict");
 425                 lp->stats.tx_errors++;
 426                 /* Try to restart the adaptor. */
 427                 hardware_init(dev);
 428                 dev->tbusy=0;
 429                 dev->trans_start = jiffies;
 430         }
 431 
 432         /* If some higher layer thinks we've missed an tx-done interrupt
 433            we are passed NULL. Caution: dev_tint() handles the cli()/sti()
 434            itself. */
 435         if (skb == NULL) {
 436                 dev_tint(dev);
 437                 return 0;
 438         }
 439 
 440         /* Block a timer-based transmit from overlapping.  This could better be
 441            done with atomic_swap(1, dev->tbusy), but set_bit() works as well. */
 442         if (set_bit(0, (void*)&dev->tbusy) != 0)
 443                 printk("%s: Transmitter access conflict.\n", dev->name);
 444         else {
 445                 short length = ETH_ZLEN < skb->len ? skb->len : ETH_ZLEN;
 446                 unsigned char *buf = skb->data;
 447                 int flags;
 448 
 449                 /* Disable interrupts by writing 0x00 to the Interrupt Mask Register.
 450                    This sequence must not be interrupted by an incoming packet. */
 451                 save_flags(flags);
 452                 cli();
 453                 write_reg(ioaddr, IMR, 0);
 454                 write_reg_high(ioaddr, IMR, 0);
 455                 restore_flags(flags);
 456 
 457                 write_packet(ioaddr, length, buf, dev->if_port);
 458 
 459                 lp->pac_cnt_in_tx_buf++;
 460                 if (lp->tx_unit_busy == 0) {
 461                         trigger_send(ioaddr, length);
 462                         lp->saved_tx_size = 0;                          /* Redundant */
 463                         lp->re_tx = 0;
 464                         lp->tx_unit_busy = 1;
 465                 } else
 466                         lp->saved_tx_size = length;
 467 
 468                 dev->trans_start = jiffies;
 469                 /* Re-enable the LPT interrupts. */
 470                 write_reg(ioaddr, IMR, ISR_RxOK | ISR_TxErr | ISR_TxOK);
 471                 write_reg_high(ioaddr, IMR, ISRh_RxErr);
 472         }
 473 
 474         dev_kfree_skb (skb, FREE_WRITE);
 475 
 476         return 0;
 477 }
 478 
 479 /* The typical workload of the driver:
 480    Handle the network interface interrupts. */
 481 static void
 482 net_interrupt(int reg_ptr)
     /* [previous][next][first][last][top][bottom][index][help] */
 483 {
 484         int irq = -(((struct pt_regs *)reg_ptr)->orig_eax+2);
 485         struct device *dev = (struct device *)(irq2dev_map[irq]);
 486         struct net_local *lp;
 487         int ioaddr, status, boguscount = 20;
 488         static int num_tx_since_rx = 0;
 489 
 490         if (dev == NULL) {
 491                 printk ("ATP_interrupt(): irq %d for unknown device.\n", irq);
 492                 return;
 493         }
 494         dev->interrupt = 1;
 495 
 496         ioaddr = dev->base_addr;
 497         lp = (struct net_local *)dev->priv;
 498 
 499         /* Disable additional spurious interrupts. */
 500         outb(Ctrl_SelData, ioaddr + PAR_CONTROL);
 501 
 502         /* The adaptor's output is currently the IRQ line, switch it to data. */
 503         write_reg(ioaddr, CMR2, CMR2_NULL);
 504         write_reg(ioaddr, IMR, 0);
 505 
 506         if (net_debug > 5) printk("%s: In interrupt ", dev->name);
 507     while (--boguscount > 0) {
 508                 status = read_nibble(ioaddr, ISR);
 509                 if (net_debug > 5) printk("loop status %02x..", status);
 510 
 511                 if (status & (ISR_RxOK<<3)) {
 512                         write_reg(ioaddr, ISR, ISR_RxOK); /* Clear the Rx interrupt. */
 513                         do {
 514                                 int read_status = read_nibble(ioaddr, CMR1);
 515                                 if (net_debug > 6)
 516                                         printk("handling Rx packet %02x..", read_status);
 517                                 /* We acknowledged the normal Rx interrupt, so if the interrupt
 518                                    is still outstanding we must have a Rx error. */
 519                                 if (read_status & (CMR1_IRQ << 3)) { /* Overrun. */
 520                                         lp->stats.rx_over_errors++;
 521                                         /* Set to no-accept mode long enough to remove a packet. */
 522                                         write_reg_high(ioaddr, CMR2, CMR2h_OFF);
 523                                         net_rx(dev);
 524                                         /* Clear the interrupt and return to normal Rx mode. */
 525                                         write_reg_high(ioaddr, ISR, ISRh_RxErr);
 526                                         write_reg_high(ioaddr, CMR2, lp->addr_mode);
 527                                 } else if ((read_status & (CMR1_BufEnb << 3)) == 0) {
 528                                         net_rx(dev);
 529                                         dev->last_rx = jiffies;
 530                                         num_tx_since_rx = 0;
 531                                 } else
 532                                         break;
 533                         } while (--boguscount > 0);
 534                 } else if (status & ((ISR_TxErr + ISR_TxOK)<<3)) {
 535                         if (net_debug > 6)  printk("handling Tx done..");
 536                         /* Clear the Tx interrupt.  We should check for too many failures
 537                            and reinitialize the adaptor. */
 538                         write_reg(ioaddr, ISR, ISR_TxErr + ISR_TxOK);
 539                         if (status & (ISR_TxErr<<3)) {
 540                                 lp->stats.collisions++;
 541                                 if (++lp->re_tx > 15) {
 542                                         lp->stats.tx_aborted_errors++;
 543                                         hardware_init(dev);
 544                                         break;
 545                                 }
 546                                 /* Attempt to retransmit. */
 547                                 if (net_debug > 6)  printk("attempting to ReTx");
 548                                 write_reg(ioaddr, CMR1, CMR1_ReXmit + CMR1_Xmit);
 549                         } else {
 550                                 /* Finish up the transmit. */
 551                                 lp->stats.tx_packets++;
 552                                 lp->pac_cnt_in_tx_buf--;
 553                                 if ( lp->saved_tx_size) {
 554                                         trigger_send(ioaddr, lp->saved_tx_size);
 555                                         lp->saved_tx_size = 0;
 556                                         lp->re_tx = 0;
 557                                 } else
 558                                         lp->tx_unit_busy = 0;
 559                                 dev->tbusy = 0;
 560                                 mark_bh(NET_BH);        /* Inform upper layers. */
 561                         }
 562                         num_tx_since_rx++;
 563                 } else if (num_tx_since_rx > 8
 564                                    && jiffies > dev->last_rx + 100) {
 565                         if (net_debug > 2)
 566                                 printk("%s: Missed packet? No Rx after %d Tx and %ld jiffies"
 567                                            " status %02x  CMR1 %02x.\n", dev->name,
 568                                            num_tx_since_rx, jiffies - dev->last_rx, status,
 569                                            (read_nibble(ioaddr, CMR1) >> 3) & 15);
 570                         lp->stats.rx_missed_errors++;
 571                         hardware_init(dev);
 572                         num_tx_since_rx = 0;
 573                         break;
 574                 } else
 575                         break;
 576     }
 577 
 578         /* This following code fixes a rare (and very difficult to track down)
 579            problem where the adaptor forgets its ethernet address. */
 580         {
 581                 int i;
 582                 for (i = 0; i < 6; i++)
 583                         write_reg_byte(ioaddr, PAR0 + i, dev->dev_addr[i]);
 584         }
 585 
 586         /* Tell the adaptor that it can go back to using the output line as IRQ. */
 587     write_reg(ioaddr, CMR2, CMR2_IRQOUT);
 588         /* Enable the physical interrupt line, which is sure to be low until.. */
 589         outb(Ctrl_SelData + Ctrl_IRQEN, ioaddr + PAR_CONTROL);
 590         /* .. we enable the interrupt sources. */
 591         write_reg(ioaddr, IMR, ISR_RxOK | ISR_TxErr | ISR_TxOK);
 592         write_reg_high(ioaddr, IMR, ISRh_RxErr);                        /* Hmmm, really needed? */
 593 
 594         if (net_debug > 5) printk("exiting interrupt.\n");
 595 
 596         dev->interrupt = 0;
 597 
 598         return;
 599 }
 600 
 601 /* We have a good packet(s), get it/them out of the buffers. */
 602 static void net_rx(struct device *dev)
     /* [previous][next][first][last][top][bottom][index][help] */
 603 {
 604         struct net_local *lp = (struct net_local *)dev->priv;
 605         int ioaddr = dev->base_addr;
 606 #ifdef notdef
 607         ushort header[4];
 608 #else
 609         struct rx_header rx_head;
 610 #endif
 611 
 612         /* Process the received packet. */
 613         outb(EOC+MAR, ioaddr + PAR_DATA);
 614         read_block(ioaddr, 8, (unsigned char*)&rx_head, dev->if_port);
 615         if (net_debug > 5)
 616                 printk(" rx_count %04x %04x %04x %04x..", rx_head.pad,
 617                            rx_head.rx_count, rx_head.rx_status, rx_head.cur_addr);
 618         if ((rx_head.rx_status & 0x77) != 0x01) {
 619                 lp->stats.rx_errors++;
 620                 /* Ackkk!  I don't have any documentation on what the error bits mean!
 621                    The best I can do is slap the device around a bit. */
 622                 if (net_debug > 3) printk("%s: Unknown ATP Rx error %04x.\n",
 623                                                                   dev->name, rx_head.rx_status);
 624                 hardware_init(dev);
 625                 return;
 626         } else {
 627                 /* Malloc up new buffer. */
 628                 int pkt_len = (rx_head.rx_count & 0x7ff) - 4;           /* The "-4" is omits the FCS (CRC). */
 629                 struct sk_buff *skb;
 630                 
 631                 skb = alloc_skb(pkt_len, GFP_ATOMIC);
 632                 if (skb == NULL) {
 633                         printk("%s: Memory squeeze, dropping packet.\n", dev->name);
 634                         lp->stats.rx_dropped++;
 635                         goto done;
 636                 }
 637                 skb->len = pkt_len;
 638                 skb->dev = dev;
 639                 
 640                 read_block(ioaddr, pkt_len, skb->data, dev->if_port);
 641 
 642                 if (net_debug > 6) {
 643                         unsigned char *data = skb->data;
 644                         printk(" data %02x%02x%02x %02x%02x%02x %02x%02x%02x"
 645                                    "%02x%02x%02x %02x%02x..",
 646                                    data[0], data[1], data[2], data[3], data[4], data[5],
 647                                    data[6], data[7], data[8], data[9], data[10], data[11],
 648                                    data[12], data[13]);
 649                 }
 650                 
 651                 netif_rx(skb);
 652                 lp->stats.rx_packets++;
 653         }
 654  done:
 655         write_reg(ioaddr, CMR1, CMR1_NextPkt);
 656         return;
 657 }
 658 
 659 static void read_block(short ioaddr, int length, unsigned char *p, int data_mode)
     /* [previous][next][first][last][top][bottom][index][help] */
 660 {
 661 
 662         if (data_mode <= 3) { /* Mode 0 or 1 */
 663                 outb(Ctrl_LNibRead, ioaddr + PAR_CONTROL);
 664                 outb(length == 8  ?  RdAddr | HNib | MAR  :  RdAddr | MAR,
 665                          ioaddr + PAR_DATA);
 666                 if (data_mode <= 1) { /* Mode 0 or 1 */
 667                         do  *p++ = read_byte_mode0(ioaddr);  while (--length > 0);
 668                 } else  /* Mode 2 or 3 */
 669                         do  *p++ = read_byte_mode2(ioaddr);  while (--length > 0);
 670         } else if (data_mode <= 5)
 671                 do      *p++ = read_byte_mode4(ioaddr);  while (--length > 0);
 672         else
 673                 do      *p++ = read_byte_mode6(ioaddr);  while (--length > 0);
 674 
 675     outb(EOC+HNib+MAR, ioaddr + PAR_DATA);
 676         outb(Ctrl_SelData, ioaddr + PAR_CONTROL);
 677 }
 678 
 679 /* The inverse routine to net_open(). */
 680 static int
 681 net_close(struct device *dev)
     /* [previous][next][first][last][top][bottom][index][help] */
 682 {
 683         struct net_local *lp = (struct net_local *)dev->priv;
 684         int ioaddr = dev->base_addr;
 685 
 686         dev->tbusy = 1;
 687         dev->start = 0;
 688 
 689         /* Flush the Tx and disable Rx here. */
 690         lp->addr_mode = CMR2h_OFF;
 691         write_reg_high(ioaddr, CMR2, CMR2h_OFF);
 692 
 693         /* Free the IRQ line. */
 694         outb(0x00, ioaddr + PAR_CONTROL);
 695         free_irq(dev->irq);
 696         irq2dev_map[dev->irq] = 0;
 697 
 698         /* Leave the hardware in a reset state. */
 699     write_reg_high(ioaddr, CMR1, CMR1h_RESET);
 700 
 701         return 0;
 702 }
 703 
 704 /* Get the current statistics.  This may be called with the card open or
 705    closed. */
 706 static struct enet_statistics *
 707 net_get_stats(struct device *dev)
     /* [previous][next][first][last][top][bottom][index][help] */
 708 {
 709         struct net_local *lp = (struct net_local *)dev->priv;
 710         return &lp->stats;
 711 }
 712 
 713 /* Set or clear the multicast filter for this adaptor.
 714    num_addrs == -1      Promiscuous mode, receive all packets
 715    num_addrs == 0       Normal mode, clear multicast list
 716    num_addrs > 0        Multicast mode, receive normal and MC packets, and do
 717                         best-effort filtering.
 718  */
 719 static void
 720 set_multicast_list(struct device *dev, int num_addrs, void *addrs)
     /* [previous][next][first][last][top][bottom][index][help] */
 721 {
 722         struct net_local *lp = (struct net_local *)dev->priv;
 723         short ioaddr = dev->base_addr;
 724         lp->addr_mode = num_addrs ? CMR2h_PROMISC : CMR2h_Normal;
 725         write_reg_high(ioaddr, CMR2, lp->addr_mode);
 726 }
 727 
 728 /*
 729  * Local variables:
 730  *  compile-command: "gcc -D__KERNEL__ -I/usr/src/linux/net/inet -Wall -Wstrict-prototypes -O6 -m486 -c atp.c"
 731  *  version-control: t
 732  *  kept-new-versions: 5
 733  *  tab-width: 4
 734  * End:
 735  */

/* [previous][next][first][last][top][bottom][index][help] */