arch/all-pc/boot/grub/netboot/epic100.c

   1 /* epic100.c: A SMC 83c170 EPIC/100 fast ethernet driver for Etherboot */
   2
   3 #define LINUX_OUT_MACROS
   4
   5 #include "etherboot.h"
   6 #include "nic.h"
   7 #include "cards.h"
   8 #include "timer.h"
   9 #include "epic100.h"
  10
  11 #undef  virt_to_bus
  12 #define virt_to_bus(x)  ((unsigned long)x)
  13
  14 #define TX_RING_SIZE    2       /* use at least 2 buffers for TX */
  15 #define RX_RING_SIZE    2
  16
  17 #define PKT_BUF_SZ      1536    /* Size of each temporary Tx/Rx buffer.*/
  18
  19 /*
  20 #define DEBUG_RX
  21 #define DEBUG_TX
  22 #define DEBUG_EEPROM
  23 */
  24
  25 #define EPIC_DEBUG 0    /* debug level */
  26
  27 /* The EPIC100 Rx and Tx buffer descriptors. */
  28 struct epic_rx_desc {
  29     unsigned short status;
  30     unsigned short rxlength;
  31     unsigned long  bufaddr;
  32     unsigned short buflength;
  33     unsigned short control;
  34     unsigned long  next;
  35 };
  36
  37 /* description of the tx descriptors control bits commonly used */
  38 #define TD_STDFLAGS     TD_LASTDESC
  39
  40 struct epic_tx_desc {
  41     unsigned short status;
  42     unsigned short txlength;
  43     unsigned long  bufaddr;
  44     unsigned short buflength;
  45     unsigned short control;
  46     unsigned long  next;
  47 };
  48
  49 #define delay(nanosec)   do { int _i = 3; while (--_i > 0) \
  50                                      { __SLOW_DOWN_IO; }} while (0)
  51
  52 static void     epic100_open(void);
  53 static void     epic100_init_ring(void);
  54 static void     epic100_disable(struct nic *nic);
  55 static int      epic100_poll(struct nic *nic);
  56 static void     epic100_transmit(struct nic *nic, const char *destaddr,
  57                                  unsigned int type, unsigned int len, const char *data);
  58 static int      read_eeprom(int location);
  59 static int      mii_read(int phy_id, int location);
  60
  61 static int      ioaddr;
  62
  63 static int      command;
  64 static int      intstat;
  65 static int      intmask;
  66 static int      genctl ;
  67 static int      eectl  ;
  68 static int      test   ;
  69 static int      mmctl  ;
  70 static int      mmdata ;
  71 static int      lan0   ;
  72 static int      rxcon  ;
  73 static int      txcon  ;
  74 static int      prcdar ;
  75 static int      ptcdar ;
  76 static int      eththr ;
  77
  78 static unsigned int     cur_rx, cur_tx;         /* The next free ring entry */
  79 #ifdef  DEBUG_EEPROM
  80 static unsigned short   eeprom[64];
  81 #endif
  82 static signed char      phys[4];                /* MII device addresses. */
  83 static struct epic_rx_desc      rx_ring[RX_RING_SIZE];
  84 static struct epic_tx_desc      tx_ring[TX_RING_SIZE];
  85 #ifdef  USE_LOWMEM_BUFFER
  86 #define rx_packet ((char *)0x10000 - PKT_BUF_SZ * RX_RING_SIZE)
  87 #define tx_packet ((char *)0x10000 - PKT_BUF_SZ * RX_RING_SIZE - PKT_BUF_SZ * TX_RING_SIZE)
  88 #else
  89 static char             rx_packet[PKT_BUF_SZ * RX_RING_SIZE];
  90 static char             tx_packet[PKT_BUF_SZ * TX_RING_SIZE];
  91 #endif
  92
  93 /***********************************************************************/
  94 /*                    Externally visible functions                     */
  95 /***********************************************************************/
  96
  97     static void
  98 epic100_reset(struct nic *nic)
  99 {
 100     /* Soft reset the chip. */
 101     outl(GC_SOFT_RESET, genctl);
 102 }
 103
 104     struct nic*
 105 epic100_probe(struct nic *nic, unsigned short *probeaddrs)
 106 {
 107     unsigned short sum = 0;
 108     unsigned short value;
 109     int i;
 110     unsigned short* ap;
 111     unsigned int phy, phy_idx;
 112
 113     if (probeaddrs == 0 || probeaddrs[0] == 0)
 114         return 0;
 115
 116     /* Ideally we would detect all network cards in slot order.  That would
 117        be best done a central PCI probe dispatch, which wouldn't work
 118        well with the current structure.  So instead we detect just the
 119        Epic cards in slot order. */
 120
 121     ioaddr = probeaddrs[0] & ~3; /* Mask the bit that says "this is an io addr" */
 122
 123     /* compute all used static epic100 registers address */
 124     command = ioaddr + COMMAND;         /* Control Register */
 125     intstat = ioaddr + INTSTAT;         /* Interrupt Status */
 126     intmask = ioaddr + INTMASK;         /* Interrupt Mask */
 127     genctl  = ioaddr + GENCTL;          /* General Control */
 128     eectl   = ioaddr + EECTL;           /* EEPROM Control  */
 129     test    = ioaddr + TEST;            /* Test register (clocks) */
 130     mmctl   = ioaddr + MMCTL;           /* MII Management Interface Control */
 131     mmdata  = ioaddr + MMDATA;          /* MII Management Interface Data */
 132     lan0    = ioaddr + LAN0;            /* MAC address. (0x40-0x48) */
 133     rxcon   = ioaddr + RXCON;           /* Receive Control */
 134     txcon   = ioaddr + TXCON;           /* Transmit Control */
 135     prcdar  = ioaddr + PRCDAR;          /* PCI Receive Current Descr Address */
 136     ptcdar  = ioaddr + PTCDAR;          /* PCI Transmit Current Descr Address */
 137     eththr  = ioaddr + ETHTHR;          /* Early Transmit Threshold */
 138
 139     /* Reset the chip & bring it out of low-power mode. */
 140     outl(GC_SOFT_RESET, genctl);
 141
 142     /* Disable ALL interrupts by setting the interrupt mask. */
 143     outl(INTR_DISABLE, intmask);
 144
 145     /*
 146      * set the internal clocks:
 147      * Application Note 7.15 says:
 148      *    In order to set the CLOCK TEST bit in the TEST register,
 149      *    perform the following:
 150      *
 151      *        Write 0x0008 to the test register at least sixteen
 152      *        consecutive times.
 153      *
 154      * The CLOCK TEST bit is Write-Only. Writing it several times
 155      * consecutively insures a successful write to the bit...
 156      */
 157
 158     for (i = 0; i < 16; i++) {
 159         outl(0x00000008, test);
 160     }
 161
 162 #ifdef  DEBUG_EEPROM
 163     for (i = 0; i < 64; i++) {
 164         value = read_eeprom(i);
 165         eeprom[i] = value;
 166         sum += value;
 167     }
 168
 169 #if     (EPIC_DEBUG > 1)
 170     printf("EEPROM contents\n");
 171     for (i = 0; i < 64; i++) {
 172         printf(" %hhX%s", eeprom[i], i % 16 == 15 ? "\n" : "");
 173     }
 174 #endif
 175 #endif
 176
 177     /* This could also be read from the EEPROM. */
 178     ap = (unsigned short*)nic->node_addr;
 179     for (i = 0; i < 3; i++)
 180         *ap++ = inw(lan0 + i*4);
 181
 182     printf(" I/O %#hX %! ", ioaddr, nic->node_addr);
 183
 184     /* Find the connected MII xcvrs. */
 185     for (phy = 0, phy_idx = 0; phy < 32 && phy_idx < sizeof(phys); phy++) {
 186         int mii_status = mii_read(phy, 0);
 187
 188         if (mii_status != 0xffff  && mii_status != 0x0000) {
 189             phys[phy_idx++] = phy;
 190 #if     (EPIC_DEBUG > 1)
 191             printf("MII transceiver found at address %d.\n", phy);
 192 #endif
 193         }
 194     }
 195     if (phy_idx == 0) {
 196 #if     (EPIC_DEBUG > 1)
 197         printf("***WARNING***: No MII transceiver found!\n");
 198 #endif
 199         /* Use the known PHY address of the EPII. */
 200         phys[0] = 3;
 201     }
 202
 203     epic100_open();
 204
 205     nic->reset    = epic100_reset;
 206     nic->poll     = epic100_poll;
 207     nic->transmit = epic100_transmit;
 208     nic->disable  = epic100_disable;
 209
 210     return nic;
 211 }
 212
 213     static void
 214 epic100_open(void)
 215 {
 216     int mii_reg5;
 217     int full_duplex = 0;
 218     unsigned long tmp;
 219
 220     epic100_init_ring();
 221
 222     /* Pull the chip out of low-power mode, and set for PCI read multiple. */
 223     outl(GC_RX_FIFO_THR_64 | GC_MRC_READ_MULT | GC_ONE_COPY, genctl);
 224
 225     outl(TX_FIFO_THRESH, eththr);
 226
 227     tmp = TC_EARLY_TX_ENABLE | TX_SLOT_TIME;
 228
 229     mii_reg5 = mii_read(phys[0], 5);
 230     if (mii_reg5 != 0xffff && (mii_reg5 & 0x0100)) {
 231         full_duplex = 1;
 232         printf(" full-duplex mode");
 233         tmp |= TC_LM_FULL_DPX;
 234     } else
 235         tmp |= TC_LM_NORMAL;
 236
 237     outl(tmp, txcon);
 238
 239     /* Give adress of RX and TX ring to the chip */
 240     outl(virt_to_bus(&rx_ring), prcdar);
 241     outl(virt_to_bus(&tx_ring), ptcdar);
 242
 243     /* Start the chip's Rx process: receive unicast and broadcast */
 244     outl(0x04, rxcon);
 245     outl(CR_START_RX | CR_QUEUE_RX, command);
 246
 247     putchar('\n');
 248 }
 249
 250 /* Initialize the Rx and Tx rings. */
 251     static void
 252 epic100_init_ring(void)
 253 {
 254     int i;
 255     char* p;
 256
 257     cur_rx = cur_tx = 0;
 258
 259     p = &rx_packet[0];
 260     for (i = 0; i < RX_RING_SIZE; i++) {
 261         rx_ring[i].status    = RRING_OWN;       /* Owned by Epic chip */
 262         rx_ring[i].buflength = PKT_BUF_SZ;
 263         rx_ring[i].bufaddr   = virt_to_bus(p + (PKT_BUF_SZ * i));
 264         rx_ring[i].control   = 0;
 265         rx_ring[i].next      = virt_to_bus(&(rx_ring[i + 1]) );
 266     }
 267     /* Mark the last entry as wrapping the ring. */
 268     rx_ring[i-1].next = virt_to_bus(&rx_ring[0]);
 269
 270     /*
 271      *The Tx buffer descriptor is filled in as needed,
 272      * but we do need to clear the ownership bit.
 273      */
 274     p = &tx_packet[0];
 275
 276     for (i = 0; i < TX_RING_SIZE; i++) {
 277         tx_ring[i].status  = 0;                 /* Owned by CPU */
 278         tx_ring[i].bufaddr = virt_to_bus(p + (PKT_BUF_SZ * i));
 279         tx_ring[i].control = TD_STDFLAGS;
 280         tx_ring[i].next    = virt_to_bus(&(tx_ring[i + 1]) );
 281     }
 282     tx_ring[i-1].next = virt_to_bus(&tx_ring[0]);
 283 }
 284
 285 /* function: epic100_transmit
 286  * This transmits a packet.
 287  *
 288  * Arguments: char d[6]:          destination ethernet address.
 289  *            unsigned short t:   ethernet protocol type.
 290  *            unsigned short s:   size of the data-part of the packet.
 291  *            char *p:            the data for the packet.
 292  * returns:   void.
 293  */
 294     static void
 295 epic100_transmit(struct nic *nic, const char *destaddr, unsigned int type,
 296                  unsigned int len, const char *data)
 297 {
 298     unsigned short nstype;
 299     char* txp;
 300     int entry;
 301
 302     /* Calculate the next Tx descriptor entry. */
 303     entry = cur_tx % TX_RING_SIZE;
 304
 305     if ((tx_ring[entry].status & TRING_OWN) == TRING_OWN) {
 306         printf("eth_transmit: Unable to transmit. status=%hX. Resetting...\n",
 307                tx_ring[entry].status);
 308
 309         epic100_open();
 310         return;
 311     }
 312
 313     txp = (char*)tx_ring[entry].bufaddr;
 314
 315     memcpy(txp, destaddr, ETH_ALEN);
 316     memcpy(txp + ETH_ALEN, nic->node_addr, ETH_ALEN);
 317     nstype = htons(type);
 318     memcpy(txp + 12, (char*)&nstype, 2);
 319     memcpy(txp + ETH_HLEN, data, len);
 320
 321     len += ETH_HLEN;
 322
 323     /*
 324      * Caution: the write order is important here,
 325      * set the base address with the "ownership"
 326      * bits last.
 327      */
 328     tx_ring[entry].txlength  = (len >= 60 ? len : 60);
 329     tx_ring[entry].buflength = len;
 330     tx_ring[entry].status    = TRING_OWN;       /* Pass ownership to the chip. */
 331
 332     cur_tx++;
 333
 334     /* Trigger an immediate transmit demand. */
 335     outl(CR_QUEUE_TX, command);
 336
 337     load_timer2(10*TICKS_PER_MS);         /* timeout 10 ms for transmit */
 338     while ((tx_ring[entry].status & TRING_OWN) && timer2_running())
 339         /* Wait */;
 340
 341     if ((tx_ring[entry].status & TRING_OWN) != 0)
 342         printf("Oops, transmitter timeout, status=%hX\n",
 343             tx_ring[entry].status);
 344 }
 345
 346 /* function: epic100_poll / eth_poll
 347  * This receives a packet from the network.
 348  *
 349  * Arguments: none
 350  *
 351  * returns:   1 if a packet was received.
 352  *            0 if no pacet was received.
 353  * side effects:
 354  *            returns the packet in the array nic->packet.
 355  *            returns the length of the packet in nic->packetlen.
 356  */
 357
 358     static int
 359 epic100_poll(struct nic *nic)
 360 {
 361     int entry;
 362     int status;
 363     int retcode;
 364
 365     entry = cur_rx % RX_RING_SIZE;
 366
 367     if ((status = rx_ring[entry].status & RRING_OWN) == RRING_OWN)
 368         return (0);
 369
 370     /* We own the next entry, it's a new packet. Send it up. */
 371
 372 #if     (EPIC_DEBUG > 4)
 373     printf("epic_poll: entry %d status %hX\n", entry, status);
 374 #endif
 375
 376     cur_rx++;
 377     if (status & 0x2000) {
 378         printf("epic_poll: Giant packet\n");
 379         retcode = 0;
 380     } else if (status & 0x0006) {
 381         /* Rx Frame errors are counted in hardware. */
 382         printf("epic_poll: Frame received with errors\n");
 383         retcode = 0;
 384     } else {
 385         /* Omit the four octet CRC from the length. */
 386         nic->packetlen = rx_ring[entry].rxlength - 4;
 387         memcpy(nic->packet, (char*)rx_ring[entry].bufaddr, nic->packetlen);
 388         retcode = 1;
 389     }
 390
 391     /* Clear all error sources. */
 392     outl(status & INTR_CLEARERRS, intstat);
 393
 394     /* Give the descriptor back to the chip */
 395     rx_ring[entry].status = RRING_OWN;
 396
 397     /* Restart Receiver */
 398     outl(CR_START_RX | CR_QUEUE_RX, command);
 399
 400     return retcode;
 401 }
 402
 403
 404     static void
 405 epic100_disable(struct nic *nic)
 406 {
 407 }
 408
 409
 410 #ifdef  DEBUG_EEPROM
 411 /* Serial EEPROM section. */
 412
 413 /*  EEPROM_Ctrl bits. */
 414 #define EE_SHIFT_CLK    0x04    /* EEPROM shift clock. */
 415 #define EE_CS           0x02    /* EEPROM chip select. */
 416 #define EE_DATA_WRITE   0x08    /* EEPROM chip data in. */
 417 #define EE_WRITE_0      0x01
 418 #define EE_WRITE_1      0x09
 419 #define EE_DATA_READ    0x10    /* EEPROM chip data out. */
 420 #define EE_ENB          (0x0001 | EE_CS)
 421
 422 /* The EEPROM commands include the alway-set leading bit. */
 423 #define EE_WRITE_CMD    (5 << 6)
 424 #define EE_READ_CMD     (6 << 6)
 425 #define EE_ERASE_CMD    (7 << 6)
 426
 427 #define eeprom_delay(n) delay(n)
 428
 429     static int
 430 read_eeprom(int location)
 431 {
 432     int i;
 433     int retval = 0;
 434     int read_cmd = location | EE_READ_CMD;
 435
 436     outl(EE_ENB & ~EE_CS, eectl);
 437     outl(EE_ENB, eectl);
 438
 439     /* Shift the read command bits out. */
 440     for (i = 10; i >= 0; i--) {
 441         short dataval = (read_cmd & (1 << i)) ? EE_DATA_WRITE : 0;
 442         outl(EE_ENB | dataval, eectl);
 443         eeprom_delay(100);
 444         outl(EE_ENB | dataval | EE_SHIFT_CLK, eectl);
 445         eeprom_delay(150);
 446         outl(EE_ENB | dataval, eectl);  /* Finish EEPROM a clock tick. */
 447         eeprom_delay(250);
 448     }
 449     outl(EE_ENB, eectl);
 450
 451     for (i = 16; i > 0; i--) {
 452         outl(EE_ENB | EE_SHIFT_CLK, eectl);
 453         eeprom_delay(100);
 454         retval = (retval << 1) | ((inl(eectl) & EE_DATA_READ) ? 1 : 0);
 455         outl(EE_ENB, eectl);
 456         eeprom_delay(100);
 457     }
 458
 459     /* Terminate the EEPROM access. */
 460     outl(EE_ENB & ~EE_CS, eectl);
 461     return retval;
 462 }
 463 #endif
 464
 465
 466 #define MII_READOP      1
 467 #define MII_WRITEOP     2
 468
 469     static int
 470 mii_read(int phy_id, int location)
 471 {
 472     int i;
 473
 474     outl((phy_id << 9) | (location << 4) | MII_READOP, mmctl);
 475     /* Typical operation takes < 50 ticks. */
 476
 477     for (i = 4000; i > 0; i--)
 478         if ((inl(mmctl) & MII_READOP) == 0)
 479             break;
 480     return inw(mmdata);
 481 }