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 } 482