1 /* 2 * Copyright (c) 1996 Gardner Buchanan <gbuchanan@shl.com> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by Gardner Buchanan. 16 * 4. The name of Gardner Buchanan may not be used to endorse or promote 17 * products derived from this software without specific prior written 18 * permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 23 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 29 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 * 31 * $FreeBSD: src/sys/dev/sn/if_sn.c,v 1.7.2.3 2001/02/04 04:38:38 toshi Exp $ 32 * $DragonFly: src/sys/dev/netif/sn/if_sn.c,v 1.12 2005/01/23 20:21:31 joerg Exp $ 33 */ 34 35 /* 36 * This is a driver for SMC's 9000 series of Ethernet adapters. 37 * 38 * This FreeBSD driver is derived from the smc9194 Linux driver by 39 * Erik Stahlman and is Copyright (C) 1996 by Erik Stahlman. 40 * This driver also shamelessly borrows from the FreeBSD ep driver 41 * which is Copyright (C) 1994 Herb Peyerl <hpeyerl@novatel.ca> 42 * All rights reserved. 43 * 44 * It is set up for my SMC91C92 equipped Ampro LittleBoard embedded 45 * PC. It is adapted from Erik Stahlman's Linux driver which worked 46 * with his EFA Info*Express SVC VLB adaptor. According to SMC's databook, 47 * it will work for the entire SMC 9xxx series. (Ha Ha) 48 * 49 * "Features" of the SMC chip: 50 * 4608 byte packet memory. (for the 91C92. Others have more) 51 * EEPROM for configuration 52 * AUI/TP selection 53 * 54 * Authors: 55 * Erik Stahlman erik@vt.edu 56 * Herb Peyerl hpeyerl@novatel.ca 57 * Andres Vega Garcia avega@sophia.inria.fr 58 * Serge Babkin babkin@hq.icb.chel.su 59 * Gardner Buchanan gbuchanan@shl.com 60 * 61 * Sources: 62 * o SMC databook 63 * o "smc9194.c:v0.10(FIXED) 02/15/96 by Erik Stahlman (erik@vt.edu)" 64 * o "if_ep.c,v 1.19 1995/01/24 20:53:45 davidg Exp" 65 * 66 * Known Bugs: 67 * o The hardware multicast filter isn't used yet. 68 * o Setting of the hardware address isn't supported. 69 * o Hardware padding isn't used. 70 */ 71 72 /* 73 * Modifications for Megahertz X-Jack Ethernet Card (XJ-10BT) 74 * 75 * Copyright (c) 1996 by Tatsumi Hosokawa <hosokawa@jp.FreeBSD.org> 76 * BSD-nomads, Tokyo, Japan. 77 */ 78 /* 79 * Multicast support by Kei TANAKA <kei@pal.xerox.com> 80 * Special thanks to itojun@itojun.org 81 */ 82 83 #undef SN_DEBUG /* (by hosokawa) */ 84 85 #include <sys/param.h> 86 #include <sys/systm.h> 87 #include <sys/kernel.h> 88 #include <sys/errno.h> 89 #include <sys/sockio.h> 90 #include <sys/malloc.h> 91 #include <sys/mbuf.h> 92 #include <sys/socket.h> 93 #include <sys/syslog.h> 94 95 #include <sys/module.h> 96 #include <sys/bus.h> 97 98 #include <machine/bus.h> 99 #include <machine/resource.h> 100 #include <sys/rman.h> 101 102 #include <net/ethernet.h> 103 #include <net/if.h> 104 #include <net/if_arp.h> 105 #include <net/if_dl.h> 106 #include <net/if_types.h> 107 #include <net/if_mib.h> 108 109 #ifdef INET 110 #include <netinet/in.h> 111 #include <netinet/in_systm.h> 112 #include <netinet/in_var.h> 113 #include <netinet/ip.h> 114 #endif 115 116 #ifdef NS 117 #include <netns/ns.h> 118 #include <netns/ns_if.h> 119 #endif 120 121 #include <net/bpf.h> 122 #include <net/bpfdesc.h> 123 124 #include <machine/clock.h> 125 126 #include "if_snreg.h" 127 #include "if_snvar.h" 128 129 /* Exported variables */ 130 devclass_t sn_devclass; 131 132 static int snioctl(struct ifnet * ifp, u_long, caddr_t, struct ucred *); 133 134 static void snresume(struct ifnet *); 135 136 void sninit(void *); 137 void snread(struct ifnet *); 138 void snreset(struct sn_softc *); 139 void snstart(struct ifnet *); 140 void snstop(struct sn_softc *); 141 void snwatchdog(struct ifnet *); 142 143 static void sn_setmcast(struct sn_softc *); 144 static int sn_getmcf(struct arpcom *ac, u_char *mcf); 145 static u_int smc_crc(u_char *); 146 147 DECLARE_DUMMY_MODULE(if_sn); 148 149 /* I (GB) have been unlucky getting the hardware padding 150 * to work properly. 151 */ 152 #define SW_PAD 153 154 static const char *chip_ids[15] = { 155 NULL, NULL, NULL, 156 /* 3 */ "SMC91C90/91C92", 157 /* 4 */ "SMC91C94", 158 /* 5 */ "SMC91C95", 159 NULL, 160 /* 7 */ "SMC91C100", 161 /* 8 */ "SMC91C100FD", 162 NULL, NULL, NULL, 163 NULL, NULL, NULL 164 }; 165 166 int 167 sn_attach(device_t dev) 168 { 169 struct sn_softc *sc = device_get_softc(dev); 170 struct ifnet *ifp = &sc->arpcom.ac_if; 171 u_short i; 172 u_char *p; 173 struct ifaddr *ifa; 174 struct sockaddr_dl *sdl; 175 int rev; 176 u_short address; 177 int j; 178 179 sn_activate(dev); 180 181 snstop(sc); 182 183 sc->dev = dev; 184 sc->pages_wanted = -1; 185 186 device_printf(dev, " "); 187 188 SMC_SELECT_BANK(3); 189 rev = inw(BASE + REVISION_REG_W); 190 if (chip_ids[(rev >> 4) & 0xF]) 191 printf("%s ", chip_ids[(rev >> 4) & 0xF]); 192 193 SMC_SELECT_BANK(1); 194 i = inw(BASE + CONFIG_REG_W); 195 printf("%s\n", i & CR_AUI_SELECT ? "AUI" : "UTP"); 196 197 if (sc->pccard_enaddr) 198 for (j = 0; j < 3; j++) { 199 u_short w; 200 201 w = (u_short)sc->arpcom.ac_enaddr[j * 2] | 202 (((u_short)sc->arpcom.ac_enaddr[j * 2 + 1]) << 8); 203 outw(BASE + IAR_ADDR0_REG_W + j * 2, w); 204 } 205 206 /* 207 * Read the station address from the chip. The MAC address is bank 1, 208 * regs 4 - 9 209 */ 210 SMC_SELECT_BANK(1); 211 p = (u_char *) & sc->arpcom.ac_enaddr; 212 for (i = 0; i < 6; i += 2) { 213 address = inw(BASE + IAR_ADDR0_REG_W + i); 214 p[i + 1] = address >> 8; 215 p[i] = address & 0xFF; 216 } 217 ifp->if_softc = sc; 218 if_initname(ifp, "sn", device_get_unit(dev)); 219 ifp->if_mtu = ETHERMTU; 220 ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST; 221 ifp->if_start = snstart; 222 ifp->if_ioctl = snioctl; 223 ifp->if_watchdog = snwatchdog; 224 ifp->if_init = sninit; 225 ifp->if_snd.ifq_maxlen = IFQ_MAXLEN; 226 ifp->if_timer = 0; 227 228 ether_ifattach(ifp, sc->arpcom.ac_enaddr); 229 230 /* 231 * Fill the hardware address into ifa_addr if we find an AF_LINK 232 * entry. We need to do this so bpf's can get the hardware addr of 233 * this card. netstat likes this too! 234 */ 235 ifa = TAILQ_FIRST(&ifp->if_addrhead); 236 while ((ifa != 0) && (ifa->ifa_addr != 0) && 237 (ifa->ifa_addr->sa_family != AF_LINK)) 238 ifa = TAILQ_NEXT(ifa, ifa_link); 239 240 if ((ifa != 0) && (ifa->ifa_addr != 0)) { 241 sdl = (struct sockaddr_dl *) ifa->ifa_addr; 242 sdl->sdl_type = IFT_ETHER; 243 sdl->sdl_alen = ETHER_ADDR_LEN; 244 sdl->sdl_slen = 0; 245 bcopy(sc->arpcom.ac_enaddr, LLADDR(sdl), ETHER_ADDR_LEN); 246 } 247 248 return 0; 249 } 250 251 252 /* 253 * Reset and initialize the chip 254 */ 255 void 256 sninit(void *xsc) 257 { 258 struct sn_softc *sc = xsc; 259 struct ifnet *ifp = &sc->arpcom.ac_if; 260 int s; 261 int flags; 262 int mask; 263 264 s = splimp(); 265 266 /* 267 * This resets the registers mostly to defaults, but doesn't affect 268 * EEPROM. After the reset cycle, we pause briefly for the chip to 269 * be happy. 270 */ 271 SMC_SELECT_BANK(0); 272 outw(BASE + RECV_CONTROL_REG_W, RCR_SOFTRESET); 273 SMC_DELAY(); 274 outw(BASE + RECV_CONTROL_REG_W, 0x0000); 275 SMC_DELAY(); 276 SMC_DELAY(); 277 278 outw(BASE + TXMIT_CONTROL_REG_W, 0x0000); 279 280 /* 281 * Set the control register to automatically release succesfully 282 * transmitted packets (making the best use out of our limited 283 * memory) and to enable the EPH interrupt on certain TX errors. 284 */ 285 SMC_SELECT_BANK(1); 286 outw(BASE + CONTROL_REG_W, (CTR_AUTO_RELEASE | CTR_TE_ENABLE | 287 CTR_CR_ENABLE | CTR_LE_ENABLE)); 288 289 /* Set squelch level to 240mV (default 480mV) */ 290 flags = inw(BASE + CONFIG_REG_W); 291 flags |= CR_SET_SQLCH; 292 outw(BASE + CONFIG_REG_W, flags); 293 294 /* 295 * Reset the MMU and wait for it to be un-busy. 296 */ 297 SMC_SELECT_BANK(2); 298 outw(BASE + MMU_CMD_REG_W, MMUCR_RESET); 299 while (inw(BASE + MMU_CMD_REG_W) & MMUCR_BUSY) /* NOTHING */ 300 ; 301 302 /* 303 * Disable all interrupts 304 */ 305 outb(BASE + INTR_MASK_REG_B, 0x00); 306 307 sn_setmcast(sc); 308 309 /* 310 * Set the transmitter control. We want it enabled. 311 */ 312 flags = TCR_ENABLE; 313 314 #ifndef SW_PAD 315 /* 316 * I (GB) have been unlucky getting this to work. 317 */ 318 flags |= TCR_PAD_ENABLE; 319 #endif /* SW_PAD */ 320 321 outw(BASE + TXMIT_CONTROL_REG_W, flags); 322 323 324 /* 325 * Now, enable interrupts 326 */ 327 SMC_SELECT_BANK(2); 328 329 mask = IM_EPH_INT | 330 IM_RX_OVRN_INT | 331 IM_RCV_INT | 332 IM_TX_INT; 333 334 outb(BASE + INTR_MASK_REG_B, mask); 335 sc->intr_mask = mask; 336 sc->pages_wanted = -1; 337 338 339 /* 340 * Mark the interface running but not active. 341 */ 342 ifp->if_flags |= IFF_RUNNING; 343 ifp->if_flags &= ~IFF_OACTIVE; 344 345 /* 346 * Attempt to push out any waiting packets. 347 */ 348 snstart(ifp); 349 350 splx(s); 351 } 352 353 354 void 355 snstart(struct ifnet *ifp) 356 { 357 struct sn_softc *sc = ifp->if_softc; 358 u_int len; 359 struct mbuf *m; 360 struct mbuf *top; 361 int s, pad; 362 int mask; 363 u_short length; 364 u_short numPages; 365 u_char packet_no; 366 int time_out; 367 368 s = splimp(); 369 370 if (sc->arpcom.ac_if.if_flags & IFF_OACTIVE) { 371 splx(s); 372 return; 373 } 374 if (sc->pages_wanted != -1) { 375 splx(s); 376 printf("%s: snstart() while memory allocation pending\n", 377 ifp->if_xname); 378 return; 379 } 380 startagain: 381 382 /* 383 * Sneak a peek at the next packet 384 */ 385 m = sc->arpcom.ac_if.if_snd.ifq_head; 386 if (m == 0) { 387 splx(s); 388 return; 389 } 390 /* 391 * Compute the frame length and set pad to give an overall even 392 * number of bytes. Below we assume that the packet length is even. 393 */ 394 for (len = 0, top = m; m; m = m->m_next) 395 len += m->m_len; 396 397 pad = (len & 1); 398 399 /* 400 * We drop packets that are too large. Perhaps we should truncate 401 * them instead? 402 */ 403 if (len + pad > ETHER_MAX_LEN - ETHER_CRC_LEN) { 404 printf("%s: large packet discarded (A)\n", ifp->if_xname); 405 ++sc->arpcom.ac_if.if_oerrors; 406 IF_DEQUEUE(&sc->arpcom.ac_if.if_snd, m); 407 m_freem(m); 408 goto readcheck; 409 } 410 #ifdef SW_PAD 411 412 /* 413 * If HW padding is not turned on, then pad to ETHER_MIN_LEN. 414 */ 415 if (len < ETHER_MIN_LEN - ETHER_CRC_LEN) 416 pad = ETHER_MIN_LEN - ETHER_CRC_LEN - len; 417 418 #endif /* SW_PAD */ 419 420 length = pad + len; 421 422 /* 423 * The MMU wants the number of pages to be the number of 256 byte 424 * 'pages', minus 1 (A packet can't ever have 0 pages. We also 425 * include space for the status word, byte count and control bytes in 426 * the allocation request. 427 */ 428 numPages = (length + 6) >> 8; 429 430 431 /* 432 * Now, try to allocate the memory 433 */ 434 SMC_SELECT_BANK(2); 435 outw(BASE + MMU_CMD_REG_W, MMUCR_ALLOC | numPages); 436 437 /* 438 * Wait a short amount of time to see if the allocation request 439 * completes. Otherwise, I enable the interrupt and wait for 440 * completion asyncronously. 441 */ 442 443 time_out = MEMORY_WAIT_TIME; 444 do { 445 if (inb(BASE + INTR_STAT_REG_B) & IM_ALLOC_INT) 446 break; 447 } while (--time_out); 448 449 if (!time_out) { 450 451 /* 452 * No memory now. Oh well, wait until the chip finds memory 453 * later. Remember how many pages we were asking for and 454 * enable the allocation completion interrupt. Also set a 455 * watchdog in case we miss the interrupt. We mark the 456 * interface active since there is no point in attempting an 457 * snstart() until after the memory is available. 458 */ 459 mask = inb(BASE + INTR_MASK_REG_B) | IM_ALLOC_INT; 460 outb(BASE + INTR_MASK_REG_B, mask); 461 sc->intr_mask = mask; 462 463 sc->arpcom.ac_if.if_timer = 1; 464 sc->arpcom.ac_if.if_flags |= IFF_OACTIVE; 465 sc->pages_wanted = numPages; 466 467 splx(s); 468 return; 469 } 470 /* 471 * The memory allocation completed. Check the results. 472 */ 473 packet_no = inb(BASE + ALLOC_RESULT_REG_B); 474 if (packet_no & ARR_FAILED) { 475 printf("%s: Memory allocation failed\n", ifp->if_xname); 476 goto startagain; 477 } 478 /* 479 * We have a packet number, so tell the card to use it. 480 */ 481 outb(BASE + PACKET_NUM_REG_B, packet_no); 482 483 /* 484 * Point to the beginning of the packet 485 */ 486 outw(BASE + POINTER_REG_W, PTR_AUTOINC | 0x0000); 487 488 /* 489 * Send the packet length (+6 for status, length and control byte) 490 * and the status word (set to zeros) 491 */ 492 outw(BASE + DATA_REG_W, 0); 493 outb(BASE + DATA_REG_B, (length + 6) & 0xFF); 494 outb(BASE + DATA_REG_B, (length + 6) >> 8); 495 496 /* 497 * Get the packet from the kernel. This will include the Ethernet 498 * frame header, MAC Addresses etc. 499 */ 500 IF_DEQUEUE(&sc->arpcom.ac_if.if_snd, m); 501 502 /* 503 * Push out the data to the card. 504 */ 505 for (top = m; m != 0; m = m->m_next) { 506 507 /* 508 * Push out words. 509 */ 510 outsw(BASE + DATA_REG_W, mtod(m, caddr_t), m->m_len / 2); 511 512 /* 513 * Push out remaining byte. 514 */ 515 if (m->m_len & 1) 516 outb(BASE + DATA_REG_B, *(mtod(m, caddr_t) + m->m_len - 1)); 517 } 518 519 /* 520 * Push out padding. 521 */ 522 while (pad > 1) { 523 outw(BASE + DATA_REG_W, 0); 524 pad -= 2; 525 } 526 if (pad) 527 outb(BASE + DATA_REG_B, 0); 528 529 /* 530 * Push out control byte and unused packet byte The control byte is 0 531 * meaning the packet is even lengthed and no special CRC handling is 532 * desired. 533 */ 534 outw(BASE + DATA_REG_W, 0); 535 536 /* 537 * Enable the interrupts and let the chipset deal with it Also set a 538 * watchdog in case we miss the interrupt. 539 */ 540 mask = inb(BASE + INTR_MASK_REG_B) | (IM_TX_INT | IM_TX_EMPTY_INT); 541 outb(BASE + INTR_MASK_REG_B, mask); 542 sc->intr_mask = mask; 543 544 outw(BASE + MMU_CMD_REG_W, MMUCR_ENQUEUE); 545 546 sc->arpcom.ac_if.if_flags |= IFF_OACTIVE; 547 sc->arpcom.ac_if.if_timer = 1; 548 549 BPF_MTAP(ifp, top); 550 551 sc->arpcom.ac_if.if_opackets++; 552 m_freem(top); 553 554 555 readcheck: 556 557 /* 558 * Is another packet coming in? We don't want to overflow the tiny 559 * RX FIFO. If nothing has arrived then attempt to queue another 560 * transmit packet. 561 */ 562 if (inw(BASE + FIFO_PORTS_REG_W) & FIFO_REMPTY) 563 goto startagain; 564 565 splx(s); 566 return; 567 } 568 569 570 571 /* Resume a packet transmit operation after a memory allocation 572 * has completed. 573 * 574 * This is basically a hacked up copy of snstart() which handles 575 * a completed memory allocation the same way snstart() does. 576 * It then passes control to snstart to handle any other queued 577 * packets. 578 */ 579 static void 580 snresume(struct ifnet *ifp) 581 { 582 struct sn_softc *sc = ifp->if_softc; 583 u_int len; 584 struct mbuf *m; 585 struct mbuf *top; 586 int pad; 587 int mask; 588 u_short length; 589 u_short numPages; 590 u_short pages_wanted; 591 u_char packet_no; 592 593 if (sc->pages_wanted < 0) 594 return; 595 596 pages_wanted = sc->pages_wanted; 597 sc->pages_wanted = -1; 598 599 /* 600 * Sneak a peek at the next packet 601 */ 602 m = sc->arpcom.ac_if.if_snd.ifq_head; 603 if (m == 0) { 604 printf("%s: snresume() with nothing to send\n", ifp->if_xname); 605 return; 606 } 607 /* 608 * Compute the frame length and set pad to give an overall even 609 * number of bytes. Below we assume that the packet length is even. 610 */ 611 for (len = 0, top = m; m; m = m->m_next) 612 len += m->m_len; 613 614 pad = (len & 1); 615 616 /* 617 * We drop packets that are too large. Perhaps we should truncate 618 * them instead? 619 */ 620 if (len + pad > ETHER_MAX_LEN - ETHER_CRC_LEN) { 621 printf("%s: large packet discarded (B)\n", ifp->if_xname); 622 ++sc->arpcom.ac_if.if_oerrors; 623 IF_DEQUEUE(&sc->arpcom.ac_if.if_snd, m); 624 m_freem(m); 625 return; 626 } 627 #ifdef SW_PAD 628 629 /* 630 * If HW padding is not turned on, then pad to ETHER_MIN_LEN. 631 */ 632 if (len < ETHER_MIN_LEN - ETHER_CRC_LEN) 633 pad = ETHER_MIN_LEN - ETHER_CRC_LEN - len; 634 635 #endif /* SW_PAD */ 636 637 length = pad + len; 638 639 640 /* 641 * The MMU wants the number of pages to be the number of 256 byte 642 * 'pages', minus 1 (A packet can't ever have 0 pages. We also 643 * include space for the status word, byte count and control bytes in 644 * the allocation request. 645 */ 646 numPages = (length + 6) >> 8; 647 648 649 SMC_SELECT_BANK(2); 650 651 /* 652 * The memory allocation completed. Check the results. If it failed, 653 * we simply set a watchdog timer and hope for the best. 654 */ 655 packet_no = inb(BASE + ALLOC_RESULT_REG_B); 656 if (packet_no & ARR_FAILED) { 657 printf("%s: Memory allocation failed. Weird.\n", ifp->if_xname); 658 sc->arpcom.ac_if.if_timer = 1; 659 goto try_start; 660 } 661 /* 662 * We have a packet number, so tell the card to use it. 663 */ 664 outb(BASE + PACKET_NUM_REG_B, packet_no); 665 666 /* 667 * Now, numPages should match the pages_wanted recorded when the 668 * memory allocation was initiated. 669 */ 670 if (pages_wanted != numPages) { 671 printf("%s: memory allocation wrong size. Weird.\n", ifp->if_xname); 672 /* 673 * If the allocation was the wrong size we simply release the 674 * memory once it is granted. Wait for the MMU to be un-busy. 675 */ 676 while (inw(BASE + MMU_CMD_REG_W) & MMUCR_BUSY) /* NOTHING */ 677 ; 678 outw(BASE + MMU_CMD_REG_W, MMUCR_FREEPKT); 679 680 return; 681 } 682 /* 683 * Point to the beginning of the packet 684 */ 685 outw(BASE + POINTER_REG_W, PTR_AUTOINC | 0x0000); 686 687 /* 688 * Send the packet length (+6 for status, length and control byte) 689 * and the status word (set to zeros) 690 */ 691 outw(BASE + DATA_REG_W, 0); 692 outb(BASE + DATA_REG_B, (length + 6) & 0xFF); 693 outb(BASE + DATA_REG_B, (length + 6) >> 8); 694 695 /* 696 * Get the packet from the kernel. This will include the Ethernet 697 * frame header, MAC Addresses etc. 698 */ 699 IF_DEQUEUE(&sc->arpcom.ac_if.if_snd, m); 700 701 /* 702 * Push out the data to the card. 703 */ 704 for (top = m; m != 0; m = m->m_next) { 705 706 /* 707 * Push out words. 708 */ 709 outsw(BASE + DATA_REG_W, mtod(m, caddr_t), m->m_len / 2); 710 711 /* 712 * Push out remaining byte. 713 */ 714 if (m->m_len & 1) 715 outb(BASE + DATA_REG_B, *(mtod(m, caddr_t) + m->m_len - 1)); 716 } 717 718 /* 719 * Push out padding. 720 */ 721 while (pad > 1) { 722 outw(BASE + DATA_REG_W, 0); 723 pad -= 2; 724 } 725 if (pad) 726 outb(BASE + DATA_REG_B, 0); 727 728 /* 729 * Push out control byte and unused packet byte The control byte is 0 730 * meaning the packet is even lengthed and no special CRC handling is 731 * desired. 732 */ 733 outw(BASE + DATA_REG_W, 0); 734 735 /* 736 * Enable the interrupts and let the chipset deal with it Also set a 737 * watchdog in case we miss the interrupt. 738 */ 739 mask = inb(BASE + INTR_MASK_REG_B) | (IM_TX_INT | IM_TX_EMPTY_INT); 740 outb(BASE + INTR_MASK_REG_B, mask); 741 sc->intr_mask = mask; 742 outw(BASE + MMU_CMD_REG_W, MMUCR_ENQUEUE); 743 744 BPF_MTAP(ifp, top); 745 746 sc->arpcom.ac_if.if_opackets++; 747 m_freem(top); 748 749 try_start: 750 751 /* 752 * Now pass control to snstart() to queue any additional packets 753 */ 754 sc->arpcom.ac_if.if_flags &= ~IFF_OACTIVE; 755 snstart(ifp); 756 757 /* 758 * We've sent something, so we're active. Set a watchdog in case the 759 * TX_EMPTY interrupt is lost. 760 */ 761 sc->arpcom.ac_if.if_flags |= IFF_OACTIVE; 762 sc->arpcom.ac_if.if_timer = 1; 763 764 return; 765 } 766 767 768 void 769 sn_intr(void *arg) 770 { 771 int status, interrupts; 772 struct sn_softc *sc = (struct sn_softc *) arg; 773 struct ifnet *ifp = &sc->arpcom.ac_if; 774 int x; 775 776 /* 777 * Chip state registers 778 */ 779 u_char mask; 780 u_char packet_no; 781 u_short tx_status; 782 u_short card_stats; 783 784 /* 785 * if_ep.c did this, so I do too. Yet if_ed.c doesn't. I wonder... 786 */ 787 x = splbio(); 788 789 /* 790 * Clear the watchdog. 791 */ 792 ifp->if_timer = 0; 793 794 SMC_SELECT_BANK(2); 795 796 /* 797 * Obtain the current interrupt mask and clear the hardware mask 798 * while servicing interrupts. 799 */ 800 mask = inb(BASE + INTR_MASK_REG_B); 801 outb(BASE + INTR_MASK_REG_B, 0x00); 802 803 /* 804 * Get the set of interrupts which occurred and eliminate any which 805 * are masked. 806 */ 807 interrupts = inb(BASE + INTR_STAT_REG_B); 808 status = interrupts & mask; 809 810 /* 811 * Now, process each of the interrupt types. 812 */ 813 814 /* 815 * Receive Overrun. 816 */ 817 if (status & IM_RX_OVRN_INT) { 818 819 /* 820 * Acknowlege Interrupt 821 */ 822 SMC_SELECT_BANK(2); 823 outb(BASE + INTR_ACK_REG_B, IM_RX_OVRN_INT); 824 825 ++sc->arpcom.ac_if.if_ierrors; 826 } 827 /* 828 * Got a packet. 829 */ 830 if (status & IM_RCV_INT) { 831 #if 1 832 int packet_number; 833 834 SMC_SELECT_BANK(2); 835 packet_number = inw(BASE + FIFO_PORTS_REG_W); 836 837 if (packet_number & FIFO_REMPTY) { 838 839 /* 840 * we got called , but nothing was on the FIFO 841 */ 842 printf("sn: Receive interrupt with nothing on FIFO\n"); 843 844 goto out; 845 } 846 #endif 847 snread(ifp); 848 } 849 /* 850 * An on-card memory allocation came through. 851 */ 852 if (status & IM_ALLOC_INT) { 853 854 /* 855 * Disable this interrupt. 856 */ 857 mask &= ~IM_ALLOC_INT; 858 sc->arpcom.ac_if.if_flags &= ~IFF_OACTIVE; 859 snresume(&sc->arpcom.ac_if); 860 } 861 /* 862 * TX Completion. Handle a transmit error message. This will only be 863 * called when there is an error, because of the AUTO_RELEASE mode. 864 */ 865 if (status & IM_TX_INT) { 866 867 /* 868 * Acknowlege Interrupt 869 */ 870 SMC_SELECT_BANK(2); 871 outb(BASE + INTR_ACK_REG_B, IM_TX_INT); 872 873 packet_no = inw(BASE + FIFO_PORTS_REG_W); 874 packet_no &= FIFO_TX_MASK; 875 876 /* 877 * select this as the packet to read from 878 */ 879 outb(BASE + PACKET_NUM_REG_B, packet_no); 880 881 /* 882 * Position the pointer to the first word from this packet 883 */ 884 outw(BASE + POINTER_REG_W, PTR_AUTOINC | PTR_READ | 0x0000); 885 886 /* 887 * Fetch the TX status word. The value found here will be a 888 * copy of the EPH_STATUS_REG_W at the time the transmit 889 * failed. 890 */ 891 tx_status = inw(BASE + DATA_REG_W); 892 893 if (tx_status & EPHSR_TX_SUC) { 894 device_printf(sc->dev, 895 "Successful packet caused interrupt\n"); 896 } else { 897 ++sc->arpcom.ac_if.if_oerrors; 898 } 899 900 if (tx_status & EPHSR_LATCOL) 901 ++sc->arpcom.ac_if.if_collisions; 902 903 /* 904 * Some of these errors will have disabled transmit. 905 * Re-enable transmit now. 906 */ 907 SMC_SELECT_BANK(0); 908 909 #ifdef SW_PAD 910 outw(BASE + TXMIT_CONTROL_REG_W, TCR_ENABLE); 911 #else 912 outw(BASE + TXMIT_CONTROL_REG_W, TCR_ENABLE | TCR_PAD_ENABLE); 913 #endif /* SW_PAD */ 914 915 /* 916 * kill the failed packet. Wait for the MMU to be un-busy. 917 */ 918 SMC_SELECT_BANK(2); 919 while (inw(BASE + MMU_CMD_REG_W) & MMUCR_BUSY) /* NOTHING */ 920 ; 921 outw(BASE + MMU_CMD_REG_W, MMUCR_FREEPKT); 922 923 /* 924 * Attempt to queue more transmits. 925 */ 926 sc->arpcom.ac_if.if_flags &= ~IFF_OACTIVE; 927 snstart(&sc->arpcom.ac_if); 928 } 929 /* 930 * Transmit underrun. We use this opportunity to update transmit 931 * statistics from the card. 932 */ 933 if (status & IM_TX_EMPTY_INT) { 934 935 /* 936 * Acknowlege Interrupt 937 */ 938 SMC_SELECT_BANK(2); 939 outb(BASE + INTR_ACK_REG_B, IM_TX_EMPTY_INT); 940 941 /* 942 * Disable this interrupt. 943 */ 944 mask &= ~IM_TX_EMPTY_INT; 945 946 SMC_SELECT_BANK(0); 947 card_stats = inw(BASE + COUNTER_REG_W); 948 949 /* 950 * Single collisions 951 */ 952 sc->arpcom.ac_if.if_collisions += card_stats & ECR_COLN_MASK; 953 954 /* 955 * Multiple collisions 956 */ 957 sc->arpcom.ac_if.if_collisions += (card_stats & ECR_MCOLN_MASK) >> 4; 958 959 SMC_SELECT_BANK(2); 960 961 /* 962 * Attempt to enqueue some more stuff. 963 */ 964 sc->arpcom.ac_if.if_flags &= ~IFF_OACTIVE; 965 snstart(&sc->arpcom.ac_if); 966 } 967 /* 968 * Some other error. Try to fix it by resetting the adapter. 969 */ 970 if (status & IM_EPH_INT) { 971 snstop(sc); 972 sninit(sc); 973 } 974 975 out: 976 /* 977 * Handled all interrupt sources. 978 */ 979 980 SMC_SELECT_BANK(2); 981 982 /* 983 * Reestablish interrupts from mask which have not been deselected 984 * during this interrupt. Note that the hardware mask, which was set 985 * to 0x00 at the start of this service routine, may have been 986 * updated by one or more of the interrupt handers and we must let 987 * those new interrupts stay enabled here. 988 */ 989 mask |= inb(BASE + INTR_MASK_REG_B); 990 outb(BASE + INTR_MASK_REG_B, mask); 991 sc->intr_mask = mask; 992 993 splx(x); 994 } 995 996 void 997 snread(struct ifnet *ifp) 998 { 999 struct sn_softc *sc = ifp->if_softc; 1000 struct mbuf *m; 1001 short status; 1002 int packet_number; 1003 u_short packet_length; 1004 u_char *data; 1005 1006 SMC_SELECT_BANK(2); 1007 #if 0 1008 packet_number = inw(BASE + FIFO_PORTS_REG_W); 1009 1010 if (packet_number & FIFO_REMPTY) { 1011 1012 /* 1013 * we got called , but nothing was on the FIFO 1014 */ 1015 printf("sn: Receive interrupt with nothing on FIFO\n"); 1016 return; 1017 } 1018 #endif 1019 read_another: 1020 1021 /* 1022 * Start reading from the start of the packet. Since PTR_RCV is set, 1023 * packet number is found in FIFO_PORTS_REG_W, FIFO_RX_MASK. 1024 */ 1025 outw(BASE + POINTER_REG_W, PTR_READ | PTR_RCV | PTR_AUTOINC | 0x0000); 1026 1027 /* 1028 * First two words are status and packet_length 1029 */ 1030 status = inw(BASE + DATA_REG_W); 1031 packet_length = inw(BASE + DATA_REG_W) & RLEN_MASK; 1032 1033 /* 1034 * The packet length contains 3 extra words: status, length, and a 1035 * extra word with the control byte. 1036 */ 1037 packet_length -= 6; 1038 1039 /* 1040 * Account for receive errors and discard. 1041 */ 1042 if (status & RS_ERRORS) { 1043 ++ifp->if_ierrors; 1044 goto out; 1045 } 1046 /* 1047 * A packet is received. 1048 */ 1049 1050 /* 1051 * Adjust for odd-length packet. 1052 */ 1053 if (status & RS_ODDFRAME) 1054 packet_length++; 1055 1056 /* 1057 * Allocate a header mbuf from the kernel. 1058 */ 1059 MGETHDR(m, MB_DONTWAIT, MT_DATA); 1060 if (m == NULL) 1061 goto out; 1062 1063 m->m_pkthdr.rcvif = ifp; 1064 m->m_pkthdr.len = m->m_len = packet_length; 1065 1066 /* 1067 * Attach an mbuf cluster 1068 */ 1069 MCLGET(m, MB_DONTWAIT); 1070 1071 /* 1072 * Insist on getting a cluster 1073 */ 1074 if ((m->m_flags & M_EXT) == 0) { 1075 m_freem(m); 1076 ++ifp->if_ierrors; 1077 printf("sn: snread() kernel memory allocation problem\n"); 1078 goto out; 1079 } 1080 1081 /* 1082 * Get packet, including link layer address, from interface. 1083 */ 1084 1085 data = mtod(m, u_char *); 1086 insw(BASE + DATA_REG_W, data, packet_length >> 1); 1087 if (packet_length & 1) { 1088 data += packet_length & ~1; 1089 *data = inb(BASE + DATA_REG_B); 1090 } 1091 ++ifp->if_ipackets; 1092 1093 m->m_pkthdr.len = m->m_len = packet_length; 1094 1095 (*ifp->if_input)(ifp, m); 1096 1097 out: 1098 1099 /* 1100 * Error or good, tell the card to get rid of this packet Wait for 1101 * the MMU to be un-busy. 1102 */ 1103 SMC_SELECT_BANK(2); 1104 while (inw(BASE + MMU_CMD_REG_W) & MMUCR_BUSY) /* NOTHING */ 1105 ; 1106 outw(BASE + MMU_CMD_REG_W, MMUCR_RELEASE); 1107 1108 /* 1109 * Check whether another packet is ready 1110 */ 1111 packet_number = inw(BASE + FIFO_PORTS_REG_W); 1112 if (packet_number & FIFO_REMPTY) { 1113 return; 1114 } 1115 goto read_another; 1116 } 1117 1118 1119 /* 1120 * Handle IOCTLS. This function is completely stolen from if_ep.c 1121 * As with its progenitor, it does not handle hardware address 1122 * changes. 1123 */ 1124 static int 1125 snioctl(struct ifnet *ifp, u_long cmd, caddr_t data, struct ucred *cr) 1126 { 1127 struct sn_softc *sc = ifp->if_softc; 1128 int s, error = 0; 1129 1130 s = splimp(); 1131 1132 switch (cmd) { 1133 case SIOCSIFADDR: 1134 case SIOCGIFADDR: 1135 case SIOCSIFMTU: 1136 error = ether_ioctl(ifp, cmd, data); 1137 break; 1138 1139 case SIOCSIFFLAGS: 1140 if ((ifp->if_flags & IFF_UP) == 0 && ifp->if_flags & IFF_RUNNING) { 1141 ifp->if_flags &= ~IFF_RUNNING; 1142 snstop(sc); 1143 break; 1144 } else { 1145 /* reinitialize card on any parameter change */ 1146 sninit(sc); 1147 break; 1148 } 1149 break; 1150 1151 #ifdef notdef 1152 case SIOCGHWADDR: 1153 bcopy((caddr_t) sc->sc_addr, (caddr_t) & ifr->ifr_data, 1154 sizeof(sc->sc_addr)); 1155 break; 1156 #endif 1157 1158 case SIOCADDMULTI: 1159 /* update multicast filter list. */ 1160 sn_setmcast(sc); 1161 error = 0; 1162 break; 1163 case SIOCDELMULTI: 1164 /* update multicast filter list. */ 1165 sn_setmcast(sc); 1166 error = 0; 1167 break; 1168 default: 1169 error = EINVAL; 1170 } 1171 1172 splx(s); 1173 1174 return (error); 1175 } 1176 1177 void 1178 snreset(struct sn_softc *sc) 1179 { 1180 int s; 1181 1182 s = splimp(); 1183 snstop(sc); 1184 sninit(sc); 1185 1186 splx(s); 1187 } 1188 1189 void 1190 snwatchdog(struct ifnet *ifp) 1191 { 1192 int s; 1193 s = splimp(); 1194 sn_intr(ifp->if_softc); 1195 splx(s); 1196 } 1197 1198 1199 /* 1. zero the interrupt mask 1200 * 2. clear the enable receive flag 1201 * 3. clear the enable xmit flags 1202 */ 1203 void 1204 snstop(struct sn_softc *sc) 1205 { 1206 1207 struct ifnet *ifp = &sc->arpcom.ac_if; 1208 1209 /* 1210 * Clear interrupt mask; disable all interrupts. 1211 */ 1212 SMC_SELECT_BANK(2); 1213 outb(BASE + INTR_MASK_REG_B, 0x00); 1214 1215 /* 1216 * Disable transmitter and Receiver 1217 */ 1218 SMC_SELECT_BANK(0); 1219 outw(BASE + RECV_CONTROL_REG_W, 0x0000); 1220 outw(BASE + TXMIT_CONTROL_REG_W, 0x0000); 1221 1222 /* 1223 * Cancel watchdog. 1224 */ 1225 ifp->if_timer = 0; 1226 } 1227 1228 1229 int 1230 sn_activate(device_t dev) 1231 { 1232 struct sn_softc *sc = device_get_softc(dev); 1233 int err; 1234 1235 sc->port_rid = 0; 1236 sc->port_res = bus_alloc_resource(dev, SYS_RES_IOPORT, &sc->port_rid, 1237 0, ~0, SMC_IO_EXTENT, RF_ACTIVE); 1238 if (!sc->port_res) { 1239 #ifdef SN_DEBUG 1240 device_printf(dev, "Cannot allocate ioport\n"); 1241 #endif 1242 return ENOMEM; 1243 } 1244 1245 sc->irq_rid = 0; 1246 sc->irq_res = bus_alloc_resource(dev, SYS_RES_IRQ, &sc->irq_rid, 1247 0, ~0, 1, RF_ACTIVE); 1248 if (!sc->irq_res) { 1249 #ifdef SN_DEBUG 1250 device_printf(dev, "Cannot allocate irq\n"); 1251 #endif 1252 sn_deactivate(dev); 1253 return ENOMEM; 1254 } 1255 if ((err = bus_setup_intr(dev, sc->irq_res, INTR_TYPE_NET, sn_intr, sc, 1256 &sc->intrhand)) != 0) { 1257 sn_deactivate(dev); 1258 return err; 1259 } 1260 1261 sc->sn_io_addr = rman_get_start(sc->port_res); 1262 return (0); 1263 } 1264 1265 void 1266 sn_deactivate(device_t dev) 1267 { 1268 struct sn_softc *sc = device_get_softc(dev); 1269 1270 if (sc->intrhand) 1271 bus_teardown_intr(dev, sc->irq_res, sc->intrhand); 1272 sc->intrhand = 0; 1273 if (sc->port_res) 1274 bus_release_resource(dev, SYS_RES_IOPORT, sc->port_rid, 1275 sc->port_res); 1276 sc->port_res = 0; 1277 if (sc->irq_res) 1278 bus_release_resource(dev, SYS_RES_IRQ, sc->irq_rid, 1279 sc->irq_res); 1280 sc->irq_res = 0; 1281 return; 1282 } 1283 1284 /* 1285 * Function: sn_probe( device_t dev, int pccard ) 1286 * 1287 * Purpose: 1288 * Tests to see if a given ioaddr points to an SMC9xxx chip. 1289 * Tries to cause as little damage as possible if it's not a SMC chip. 1290 * Returns a 0 on success 1291 * 1292 * Algorithm: 1293 * (1) see if the high byte of BANK_SELECT is 0x33 1294 * (2) compare the ioaddr with the base register's address 1295 * (3) see if I recognize the chip ID in the appropriate register 1296 * 1297 * 1298 */ 1299 int 1300 sn_probe(device_t dev, int pccard) 1301 { 1302 struct sn_softc *sc = device_get_softc(dev); 1303 u_int bank; 1304 u_short revision_register; 1305 u_short base_address_register; 1306 u_short ioaddr; 1307 int err; 1308 1309 if ((err = sn_activate(dev)) != 0) 1310 return err; 1311 1312 ioaddr = sc->sn_io_addr; 1313 1314 /* 1315 * First, see if the high byte is 0x33 1316 */ 1317 bank = inw(ioaddr + BANK_SELECT_REG_W); 1318 if ((bank & BSR_DETECT_MASK) != BSR_DETECT_VALUE) { 1319 #ifdef SN_DEBUG 1320 device_printf(dev, "test1 failed\n"); 1321 #endif 1322 goto error; 1323 } 1324 /* 1325 * The above MIGHT indicate a device, but I need to write to further 1326 * test this. Go to bank 0, then test that the register still 1327 * reports the high byte is 0x33. 1328 */ 1329 outw(ioaddr + BANK_SELECT_REG_W, 0x0000); 1330 bank = inw(ioaddr + BANK_SELECT_REG_W); 1331 if ((bank & BSR_DETECT_MASK) != BSR_DETECT_VALUE) { 1332 #ifdef SN_DEBUG 1333 device_printf(dev, "test2 failed\n"); 1334 #endif 1335 goto error; 1336 } 1337 /* 1338 * well, we've already written once, so hopefully another time won't 1339 * hurt. This time, I need to switch the bank register to bank 1, so 1340 * I can access the base address register. The contents of the 1341 * BASE_ADDR_REG_W register, after some jiggery pokery, is expected 1342 * to match the I/O port address where the adapter is being probed. 1343 */ 1344 outw(ioaddr + BANK_SELECT_REG_W, 0x0001); 1345 base_address_register = inw(ioaddr + BASE_ADDR_REG_W); 1346 1347 /* 1348 * This test is nonsence on PC-card architecture, so if 1349 * pccard == 1, skip this test. (hosokawa) 1350 */ 1351 if (!pccard && (ioaddr != (base_address_register >> 3 & 0x3E0))) { 1352 1353 /* 1354 * Well, the base address register didn't match. Must not 1355 * have been a SMC chip after all. 1356 */ 1357 /* 1358 * printf("sn: ioaddr %x doesn't match card configuration 1359 * (%x)\n", ioaddr, base_address_register >> 3 & 0x3E0 ); 1360 */ 1361 1362 #ifdef SN_DEBUG 1363 device_printf(dev, "test3 failed ioaddr = 0x%x, " 1364 "base_address_register = 0x%x\n", ioaddr, 1365 base_address_register >> 3 & 0x3E0); 1366 #endif 1367 goto error; 1368 } 1369 /* 1370 * Check if the revision register is something that I recognize. 1371 * These might need to be added to later, as future revisions could 1372 * be added. 1373 */ 1374 outw(ioaddr + BANK_SELECT_REG_W, 0x3); 1375 revision_register = inw(ioaddr + REVISION_REG_W); 1376 if (!chip_ids[(revision_register >> 4) & 0xF]) { 1377 1378 /* 1379 * I don't regonize this chip, so... 1380 */ 1381 #ifdef SN_DEBUG 1382 device_printf(dev, "test4 failed\n"); 1383 #endif 1384 goto error; 1385 } 1386 /* 1387 * at this point I'll assume that the chip is an SMC9xxx. It might be 1388 * prudent to check a listing of MAC addresses against the hardware 1389 * address, or do some other tests. 1390 */ 1391 sn_deactivate(dev); 1392 return 0; 1393 error: 1394 sn_deactivate(dev); 1395 return ENXIO; 1396 } 1397 1398 #define MCFSZ 8 1399 1400 static void 1401 sn_setmcast(struct sn_softc *sc) 1402 { 1403 struct ifnet *ifp = (struct ifnet *)sc; 1404 int flags; 1405 1406 /* 1407 * Set the receiver filter. We want receive enabled and auto strip 1408 * of CRC from received packet. If we are promiscuous then set that 1409 * bit too. 1410 */ 1411 flags = RCR_ENABLE | RCR_STRIP_CRC; 1412 1413 if (ifp->if_flags & IFF_PROMISC) { 1414 flags |= RCR_PROMISC | RCR_ALMUL; 1415 } else if (ifp->if_flags & IFF_ALLMULTI) { 1416 flags |= RCR_ALMUL; 1417 } else { 1418 u_char mcf[MCFSZ]; 1419 if (sn_getmcf(&sc->arpcom, mcf)) { 1420 /* set filter */ 1421 SMC_SELECT_BANK(3); 1422 outw(BASE + MULTICAST1_REG_W, 1423 ((u_short)mcf[1] << 8) | mcf[0]); 1424 outw(BASE + MULTICAST2_REG_W, 1425 ((u_short)mcf[3] << 8) | mcf[2]); 1426 outw(BASE + MULTICAST3_REG_W, 1427 ((u_short)mcf[5] << 8) | mcf[4]); 1428 outw(BASE + MULTICAST4_REG_W, 1429 ((u_short)mcf[7] << 8) | mcf[6]); 1430 } else { 1431 flags |= RCR_ALMUL; 1432 } 1433 } 1434 SMC_SELECT_BANK(0); 1435 outw(BASE + RECV_CONTROL_REG_W, flags); 1436 } 1437 1438 static int 1439 sn_getmcf(struct arpcom *ac, u_char *mcf) 1440 { 1441 int i; 1442 u_int index, index2; 1443 u_char *af = (u_char *) mcf; 1444 struct ifmultiaddr *ifma; 1445 1446 bzero(mcf, MCFSZ); 1447 1448 for (ifma = ac->ac_if.if_multiaddrs.lh_first; ifma; 1449 ifma = ifma->ifma_link.le_next) { 1450 if (ifma->ifma_addr->sa_family != AF_LINK) 1451 return 0; 1452 index = smc_crc(LLADDR((struct sockaddr_dl *)ifma->ifma_addr)) & 0x3f; 1453 index2 = 0; 1454 for (i = 0; i < 6; i++) { 1455 index2 <<= 1; 1456 index2 |= (index & 0x01); 1457 index >>= 1; 1458 } 1459 af[index2 >> 3] |= 1 << (index2 & 7); 1460 } 1461 return 1; /* use multicast filter */ 1462 } 1463 1464 static u_int 1465 smc_crc(u_char *s) 1466 { 1467 int perByte; 1468 int perBit; 1469 const u_int poly = 0xedb88320; 1470 u_int v = 0xffffffff; 1471 u_char c; 1472 1473 for (perByte = 0; perByte < ETHER_ADDR_LEN; perByte++) { 1474 c = s[perByte]; 1475 for (perBit = 0; perBit < 8; perBit++) { 1476 v = (v >> 1)^(((v ^ c) & 0x01) ? poly : 0); 1477 c >>= 1; 1478 } 1479 } 1480 return v; 1481 } 1482