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rtl81x9.c revision 1.86
      1 /*	$NetBSD: rtl81x9.c,v 1.86 2009/04/27 14:52:50 tsutsui Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1997, 1998
      5  *	Bill Paul <wpaul (at) ctr.columbia.edu>.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by Bill Paul.
     18  * 4. Neither the name of the author nor the names of any co-contributors
     19  *    may be used to endorse or promote products derived from this software
     20  *    without specific prior written permission.
     21  *
     22  * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
     23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     25  * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR THE VOICES IN HIS HEAD
     26  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
     32  * THE POSSIBILITY OF SUCH DAMAGE.
     33  *
     34  *	FreeBSD Id: if_rl.c,v 1.17 1999/06/19 20:17:37 wpaul Exp
     35  */
     36 
     37 /*
     38  * RealTek 8129/8139 PCI NIC driver
     39  *
     40  * Supports several extremely cheap PCI 10/100 adapters based on
     41  * the RealTek chipset. Datasheets can be obtained from
     42  * www.realtek.com.tw.
     43  *
     44  * Written by Bill Paul <wpaul (at) ctr.columbia.edu>
     45  * Electrical Engineering Department
     46  * Columbia University, New York City
     47  */
     48 
     49 /*
     50  * The RealTek 8139 PCI NIC redefines the meaning of 'low end.' This is
     51  * probably the worst PCI ethernet controller ever made, with the possible
     52  * exception of the FEAST chip made by SMC. The 8139 supports bus-master
     53  * DMA, but it has a terrible interface that nullifies any performance
     54  * gains that bus-master DMA usually offers.
     55  *
     56  * For transmission, the chip offers a series of four TX descriptor
     57  * registers. Each transmit frame must be in a contiguous buffer, aligned
     58  * on a longword (32-bit) boundary. This means we almost always have to
     59  * do mbuf copies in order to transmit a frame, except in the unlikely
     60  * case where a) the packet fits into a single mbuf, and b) the packet
     61  * is 32-bit aligned within the mbuf's data area. The presence of only
     62  * four descriptor registers means that we can never have more than four
     63  * packets queued for transmission at any one time.
     64  *
     65  * Reception is not much better. The driver has to allocate a single large
     66  * buffer area (up to 64K in size) into which the chip will DMA received
     67  * frames. Because we don't know where within this region received packets
     68  * will begin or end, we have no choice but to copy data from the buffer
     69  * area into mbufs in order to pass the packets up to the higher protocol
     70  * levels.
     71  *
     72  * It's impossible given this rotten design to really achieve decent
     73  * performance at 100Mbps, unless you happen to have a 400MHz PII or
     74  * some equally overmuscled CPU to drive it.
     75  *
     76  * On the bright side, the 8139 does have a built-in PHY, although
     77  * rather than using an MDIO serial interface like most other NICs, the
     78  * PHY registers are directly accessible through the 8139's register
     79  * space. The 8139 supports autonegotiation, as well as a 64-bit multicast
     80  * filter.
     81  *
     82  * The 8129 chip is an older version of the 8139 that uses an external PHY
     83  * chip. The 8129 has a serial MDIO interface for accessing the MII where
     84  * the 8139 lets you directly access the on-board PHY registers. We need
     85  * to select which interface to use depending on the chip type.
     86  */
     87 
     88 #include <sys/cdefs.h>
     89 __KERNEL_RCSID(0, "$NetBSD: rtl81x9.c,v 1.86 2009/04/27 14:52:50 tsutsui Exp $");
     90 
     91 #include "bpfilter.h"
     92 #include "rnd.h"
     93 
     94 #include <sys/param.h>
     95 #include <sys/systm.h>
     96 #include <sys/callout.h>
     97 #include <sys/device.h>
     98 #include <sys/sockio.h>
     99 #include <sys/mbuf.h>
    100 #include <sys/malloc.h>
    101 #include <sys/kernel.h>
    102 #include <sys/socket.h>
    103 
    104 #include <uvm/uvm_extern.h>
    105 
    106 #include <net/if.h>
    107 #include <net/if_arp.h>
    108 #include <net/if_ether.h>
    109 #include <net/if_dl.h>
    110 #include <net/if_media.h>
    111 
    112 #if NBPFILTER > 0
    113 #include <net/bpf.h>
    114 #endif
    115 #if NRND > 0
    116 #include <sys/rnd.h>
    117 #endif
    118 
    119 #include <sys/bus.h>
    120 #include <machine/endian.h>
    121 
    122 #include <dev/mii/mii.h>
    123 #include <dev/mii/miivar.h>
    124 
    125 #include <dev/ic/rtl81x9reg.h>
    126 #include <dev/ic/rtl81x9var.h>
    127 
    128 static void rtk_reset(struct rtk_softc *);
    129 static void rtk_rxeof(struct rtk_softc *);
    130 static void rtk_txeof(struct rtk_softc *);
    131 static void rtk_start(struct ifnet *);
    132 static int rtk_ioctl(struct ifnet *, u_long, void *);
    133 static int rtk_init(struct ifnet *);
    134 static void rtk_stop(struct ifnet *, int);
    135 
    136 static void rtk_watchdog(struct ifnet *);
    137 
    138 static void rtk_eeprom_putbyte(struct rtk_softc *, int, int);
    139 static void rtk_mii_sync(struct rtk_softc *);
    140 static void rtk_mii_send(struct rtk_softc *, uint32_t, int);
    141 static int rtk_mii_readreg(struct rtk_softc *, struct rtk_mii_frame *);
    142 static int rtk_mii_writereg(struct rtk_softc *, struct rtk_mii_frame *);
    143 
    144 static int rtk_phy_readreg(device_t, int, int);
    145 static void rtk_phy_writereg(device_t, int, int, int);
    146 static void rtk_phy_statchg(device_t);
    147 static void rtk_tick(void *);
    148 
    149 static int rtk_enable(struct rtk_softc *);
    150 static void rtk_disable(struct rtk_softc *);
    151 
    152 static void rtk_list_tx_init(struct rtk_softc *);
    153 
    154 #define EE_SET(x)					\
    155 	CSR_WRITE_1(sc, RTK_EECMD,			\
    156 		CSR_READ_1(sc, RTK_EECMD) | (x))
    157 
    158 #define EE_CLR(x)					\
    159 	CSR_WRITE_1(sc, RTK_EECMD,			\
    160 		CSR_READ_1(sc, RTK_EECMD) & ~(x))
    161 
    162 #define EE_DELAY()	DELAY(100)
    163 
    164 #define ETHER_PAD_LEN (ETHER_MIN_LEN - ETHER_CRC_LEN)
    165 
    166 /*
    167  * Send a read command and address to the EEPROM, check for ACK.
    168  */
    169 static void
    170 rtk_eeprom_putbyte(struct rtk_softc *sc, int addr, int addr_len)
    171 {
    172 	int d, i;
    173 
    174 	d = (RTK_EECMD_READ << addr_len) | addr;
    175 
    176 	/*
    177 	 * Feed in each bit and stobe the clock.
    178 	 */
    179 	for (i = RTK_EECMD_LEN + addr_len; i > 0; i--) {
    180 		if (d & (1 << (i - 1))) {
    181 			EE_SET(RTK_EE_DATAIN);
    182 		} else {
    183 			EE_CLR(RTK_EE_DATAIN);
    184 		}
    185 		EE_DELAY();
    186 		EE_SET(RTK_EE_CLK);
    187 		EE_DELAY();
    188 		EE_CLR(RTK_EE_CLK);
    189 		EE_DELAY();
    190 	}
    191 }
    192 
    193 /*
    194  * Read a word of data stored in the EEPROM at address 'addr.'
    195  */
    196 uint16_t
    197 rtk_read_eeprom(struct rtk_softc *sc, int addr, int addr_len)
    198 {
    199 	uint16_t word;
    200 	int i;
    201 
    202 	/* Enter EEPROM access mode. */
    203 	CSR_WRITE_1(sc, RTK_EECMD, RTK_EEMODE_PROGRAM);
    204 	EE_DELAY();
    205 	EE_SET(RTK_EE_SEL);
    206 
    207 	/*
    208 	 * Send address of word we want to read.
    209 	 */
    210 	rtk_eeprom_putbyte(sc, addr, addr_len);
    211 
    212 	/*
    213 	 * Start reading bits from EEPROM.
    214 	 */
    215 	word = 0;
    216 	for (i = 16; i > 0; i--) {
    217 		EE_SET(RTK_EE_CLK);
    218 		EE_DELAY();
    219 		if (CSR_READ_1(sc, RTK_EECMD) & RTK_EE_DATAOUT)
    220 			word |= 1 << (i - 1);
    221 		EE_CLR(RTK_EE_CLK);
    222 		EE_DELAY();
    223 	}
    224 
    225 	/* Turn off EEPROM access mode. */
    226 	CSR_WRITE_1(sc, RTK_EECMD, RTK_EEMODE_OFF);
    227 
    228 	return word;
    229 }
    230 
    231 /*
    232  * MII access routines are provided for the 8129, which
    233  * doesn't have a built-in PHY. For the 8139, we fake things
    234  * up by diverting rtk_phy_readreg()/rtk_phy_writereg() to the
    235  * direct access PHY registers.
    236  */
    237 #define MII_SET(x)					\
    238 	CSR_WRITE_1(sc, RTK_MII,			\
    239 		CSR_READ_1(sc, RTK_MII) | (x))
    240 
    241 #define MII_CLR(x)					\
    242 	CSR_WRITE_1(sc, RTK_MII,			\
    243 		CSR_READ_1(sc, RTK_MII) & ~(x))
    244 
    245 /*
    246  * Sync the PHYs by setting data bit and strobing the clock 32 times.
    247  */
    248 static void
    249 rtk_mii_sync(struct rtk_softc *sc)
    250 {
    251 	int i;
    252 
    253 	MII_SET(RTK_MII_DIR|RTK_MII_DATAOUT);
    254 
    255 	for (i = 0; i < 32; i++) {
    256 		MII_SET(RTK_MII_CLK);
    257 		DELAY(1);
    258 		MII_CLR(RTK_MII_CLK);
    259 		DELAY(1);
    260 	}
    261 }
    262 
    263 /*
    264  * Clock a series of bits through the MII.
    265  */
    266 static void
    267 rtk_mii_send(struct rtk_softc *sc, uint32_t bits, int cnt)
    268 {
    269 	int i;
    270 
    271 	MII_CLR(RTK_MII_CLK);
    272 
    273 	for (i = cnt; i > 0; i--) {
    274 		if (bits & (1 << (i - 1))) {
    275 			MII_SET(RTK_MII_DATAOUT);
    276 		} else {
    277 			MII_CLR(RTK_MII_DATAOUT);
    278 		}
    279 		DELAY(1);
    280 		MII_CLR(RTK_MII_CLK);
    281 		DELAY(1);
    282 		MII_SET(RTK_MII_CLK);
    283 	}
    284 }
    285 
    286 /*
    287  * Read an PHY register through the MII.
    288  */
    289 static int
    290 rtk_mii_readreg(struct rtk_softc *sc, struct rtk_mii_frame *frame)
    291 {
    292 	int i, ack, s;
    293 
    294 	s = splnet();
    295 
    296 	/*
    297 	 * Set up frame for RX.
    298 	 */
    299 	frame->mii_stdelim = RTK_MII_STARTDELIM;
    300 	frame->mii_opcode = RTK_MII_READOP;
    301 	frame->mii_turnaround = 0;
    302 	frame->mii_data = 0;
    303 
    304 	CSR_WRITE_2(sc, RTK_MII, 0);
    305 
    306 	/*
    307 	 * Turn on data xmit.
    308 	 */
    309 	MII_SET(RTK_MII_DIR);
    310 
    311 	rtk_mii_sync(sc);
    312 
    313 	/*
    314 	 * Send command/address info.
    315 	 */
    316 	rtk_mii_send(sc, frame->mii_stdelim, 2);
    317 	rtk_mii_send(sc, frame->mii_opcode, 2);
    318 	rtk_mii_send(sc, frame->mii_phyaddr, 5);
    319 	rtk_mii_send(sc, frame->mii_regaddr, 5);
    320 
    321 	/* Idle bit */
    322 	MII_CLR((RTK_MII_CLK|RTK_MII_DATAOUT));
    323 	DELAY(1);
    324 	MII_SET(RTK_MII_CLK);
    325 	DELAY(1);
    326 
    327 	/* Turn off xmit. */
    328 	MII_CLR(RTK_MII_DIR);
    329 
    330 	/* Check for ack */
    331 	MII_CLR(RTK_MII_CLK);
    332 	DELAY(1);
    333 	ack = CSR_READ_2(sc, RTK_MII) & RTK_MII_DATAIN;
    334 	MII_SET(RTK_MII_CLK);
    335 	DELAY(1);
    336 
    337 	/*
    338 	 * Now try reading data bits. If the ack failed, we still
    339 	 * need to clock through 16 cycles to keep the PHY(s) in sync.
    340 	 */
    341 	if (ack) {
    342 		for (i = 0; i < 16; i++) {
    343 			MII_CLR(RTK_MII_CLK);
    344 			DELAY(1);
    345 			MII_SET(RTK_MII_CLK);
    346 			DELAY(1);
    347 		}
    348 		goto fail;
    349 	}
    350 
    351 	for (i = 16; i > 0; i--) {
    352 		MII_CLR(RTK_MII_CLK);
    353 		DELAY(1);
    354 		if (!ack) {
    355 			if (CSR_READ_2(sc, RTK_MII) & RTK_MII_DATAIN)
    356 				frame->mii_data |= 1 << (i - 1);
    357 			DELAY(1);
    358 		}
    359 		MII_SET(RTK_MII_CLK);
    360 		DELAY(1);
    361 	}
    362 
    363  fail:
    364 	MII_CLR(RTK_MII_CLK);
    365 	DELAY(1);
    366 	MII_SET(RTK_MII_CLK);
    367 	DELAY(1);
    368 
    369 	splx(s);
    370 
    371 	if (ack)
    372 		return 1;
    373 	return 0;
    374 }
    375 
    376 /*
    377  * Write to a PHY register through the MII.
    378  */
    379 static int
    380 rtk_mii_writereg(struct rtk_softc *sc, struct rtk_mii_frame *frame)
    381 {
    382 	int s;
    383 
    384 	s = splnet();
    385 	/*
    386 	 * Set up frame for TX.
    387 	 */
    388 	frame->mii_stdelim = RTK_MII_STARTDELIM;
    389 	frame->mii_opcode = RTK_MII_WRITEOP;
    390 	frame->mii_turnaround = RTK_MII_TURNAROUND;
    391 
    392 	/*
    393 	 * Turn on data output.
    394 	 */
    395 	MII_SET(RTK_MII_DIR);
    396 
    397 	rtk_mii_sync(sc);
    398 
    399 	rtk_mii_send(sc, frame->mii_stdelim, 2);
    400 	rtk_mii_send(sc, frame->mii_opcode, 2);
    401 	rtk_mii_send(sc, frame->mii_phyaddr, 5);
    402 	rtk_mii_send(sc, frame->mii_regaddr, 5);
    403 	rtk_mii_send(sc, frame->mii_turnaround, 2);
    404 	rtk_mii_send(sc, frame->mii_data, 16);
    405 
    406 	/* Idle bit. */
    407 	MII_SET(RTK_MII_CLK);
    408 	DELAY(1);
    409 	MII_CLR(RTK_MII_CLK);
    410 	DELAY(1);
    411 
    412 	/*
    413 	 * Turn off xmit.
    414 	 */
    415 	MII_CLR(RTK_MII_DIR);
    416 
    417 	splx(s);
    418 
    419 	return 0;
    420 }
    421 
    422 static int
    423 rtk_phy_readreg(device_t self, int phy, int reg)
    424 {
    425 	struct rtk_softc *sc = device_private(self);
    426 	struct rtk_mii_frame frame;
    427 	int rval;
    428 	int rtk8139_reg;
    429 
    430 	if ((sc->sc_quirk & RTKQ_8129) == 0) {
    431 		if (phy != 7)
    432 			return 0;
    433 
    434 		switch (reg) {
    435 		case MII_BMCR:
    436 			rtk8139_reg = RTK_BMCR;
    437 			break;
    438 		case MII_BMSR:
    439 			rtk8139_reg = RTK_BMSR;
    440 			break;
    441 		case MII_ANAR:
    442 			rtk8139_reg = RTK_ANAR;
    443 			break;
    444 		case MII_ANER:
    445 			rtk8139_reg = RTK_ANER;
    446 			break;
    447 		case MII_ANLPAR:
    448 			rtk8139_reg = RTK_LPAR;
    449 			break;
    450 		default:
    451 #if 0
    452 			printf("%s: bad phy register\n", device_xname(self));
    453 #endif
    454 			return 0;
    455 		}
    456 		rval = CSR_READ_2(sc, rtk8139_reg);
    457 		return rval;
    458 	}
    459 
    460 	memset(&frame, 0, sizeof(frame));
    461 
    462 	frame.mii_phyaddr = phy;
    463 	frame.mii_regaddr = reg;
    464 	rtk_mii_readreg(sc, &frame);
    465 
    466 	return frame.mii_data;
    467 }
    468 
    469 static void
    470 rtk_phy_writereg(device_t self, int phy, int reg, int data)
    471 {
    472 	struct rtk_softc *sc = device_private(self);
    473 	struct rtk_mii_frame frame;
    474 	int rtk8139_reg;
    475 
    476 	if ((sc->sc_quirk & RTKQ_8129) == 0) {
    477 		if (phy != 7)
    478 			return;
    479 
    480 		switch (reg) {
    481 		case MII_BMCR:
    482 			rtk8139_reg = RTK_BMCR;
    483 			break;
    484 		case MII_BMSR:
    485 			rtk8139_reg = RTK_BMSR;
    486 			break;
    487 		case MII_ANAR:
    488 			rtk8139_reg = RTK_ANAR;
    489 			break;
    490 		case MII_ANER:
    491 			rtk8139_reg = RTK_ANER;
    492 			break;
    493 		case MII_ANLPAR:
    494 			rtk8139_reg = RTK_LPAR;
    495 			break;
    496 		default:
    497 #if 0
    498 			printf("%s: bad phy register\n", device_xname(self));
    499 #endif
    500 			return;
    501 		}
    502 		CSR_WRITE_2(sc, rtk8139_reg, data);
    503 		return;
    504 	}
    505 
    506 	memset(&frame, 0, sizeof(frame));
    507 
    508 	frame.mii_phyaddr = phy;
    509 	frame.mii_regaddr = reg;
    510 	frame.mii_data = data;
    511 
    512 	rtk_mii_writereg(sc, &frame);
    513 }
    514 
    515 static void
    516 rtk_phy_statchg(device_t v)
    517 {
    518 
    519 	/* Nothing to do. */
    520 }
    521 
    522 #define	rtk_calchash(addr) \
    523 	(ether_crc32_be((addr), ETHER_ADDR_LEN) >> 26)
    524 
    525 /*
    526  * Program the 64-bit multicast hash filter.
    527  */
    528 void
    529 rtk_setmulti(struct rtk_softc *sc)
    530 {
    531 	struct ifnet *ifp;
    532 	uint32_t hashes[2] = { 0, 0 };
    533 	uint32_t rxfilt;
    534 	struct ether_multi *enm;
    535 	struct ether_multistep step;
    536 	int h, mcnt;
    537 
    538 	ifp = &sc->ethercom.ec_if;
    539 
    540 	rxfilt = CSR_READ_4(sc, RTK_RXCFG);
    541 
    542 	if (ifp->if_flags & IFF_PROMISC) {
    543  allmulti:
    544 		ifp->if_flags |= IFF_ALLMULTI;
    545 		rxfilt |= RTK_RXCFG_RX_MULTI;
    546 		CSR_WRITE_4(sc, RTK_RXCFG, rxfilt);
    547 		CSR_WRITE_4(sc, RTK_MAR0, 0xFFFFFFFF);
    548 		CSR_WRITE_4(sc, RTK_MAR4, 0xFFFFFFFF);
    549 		return;
    550 	}
    551 
    552 	/* first, zot all the existing hash bits */
    553 	CSR_WRITE_4(sc, RTK_MAR0, 0);
    554 	CSR_WRITE_4(sc, RTK_MAR4, 0);
    555 
    556 	/* now program new ones */
    557 	ETHER_FIRST_MULTI(step, &sc->ethercom, enm);
    558 	mcnt = 0;
    559 	while (enm != NULL) {
    560 		if (memcmp(enm->enm_addrlo, enm->enm_addrhi,
    561 		    ETHER_ADDR_LEN) != 0)
    562 			goto allmulti;
    563 
    564 		h = rtk_calchash(enm->enm_addrlo);
    565 		if (h < 32)
    566 			hashes[0] |= (1 << h);
    567 		else
    568 			hashes[1] |= (1 << (h - 32));
    569 		mcnt++;
    570 		ETHER_NEXT_MULTI(step, enm);
    571 	}
    572 
    573 	ifp->if_flags &= ~IFF_ALLMULTI;
    574 
    575 	if (mcnt)
    576 		rxfilt |= RTK_RXCFG_RX_MULTI;
    577 	else
    578 		rxfilt &= ~RTK_RXCFG_RX_MULTI;
    579 
    580 	CSR_WRITE_4(sc, RTK_RXCFG, rxfilt);
    581 
    582 	/*
    583 	 * For some unfathomable reason, RealTek decided to reverse
    584 	 * the order of the multicast hash registers in the PCI Express
    585 	 * parts. This means we have to write the hash pattern in reverse
    586 	 * order for those devices.
    587 	 */
    588 	if ((sc->sc_quirk & RTKQ_PCIE) != 0) {
    589 		CSR_WRITE_4(sc, RTK_MAR0, bswap32(hashes[1]));
    590 		CSR_WRITE_4(sc, RTK_MAR4, bswap32(hashes[0]));
    591 	} else {
    592 		CSR_WRITE_4(sc, RTK_MAR0, hashes[0]);
    593 		CSR_WRITE_4(sc, RTK_MAR4, hashes[1]);
    594 	}
    595 }
    596 
    597 void
    598 rtk_reset(struct rtk_softc *sc)
    599 {
    600 	int i;
    601 
    602 	CSR_WRITE_1(sc, RTK_COMMAND, RTK_CMD_RESET);
    603 
    604 	for (i = 0; i < RTK_TIMEOUT; i++) {
    605 		DELAY(10);
    606 		if ((CSR_READ_1(sc, RTK_COMMAND) & RTK_CMD_RESET) == 0)
    607 			break;
    608 	}
    609 	if (i == RTK_TIMEOUT)
    610 		printf("%s: reset never completed!\n",
    611 		    device_xname(sc->sc_dev));
    612 }
    613 
    614 /*
    615  * Attach the interface. Allocate softc structures, do ifmedia
    616  * setup and ethernet/BPF attach.
    617  */
    618 void
    619 rtk_attach(struct rtk_softc *sc)
    620 {
    621 	device_t self = sc->sc_dev;
    622 	struct ifnet *ifp;
    623 	struct rtk_tx_desc *txd;
    624 	uint16_t val;
    625 	uint8_t eaddr[ETHER_ADDR_LEN];
    626 	int error;
    627 	int i, addr_len;
    628 
    629 	callout_init(&sc->rtk_tick_ch, 0);
    630 
    631 	/*
    632 	 * Check EEPROM type 9346 or 9356.
    633 	 */
    634 	if (rtk_read_eeprom(sc, RTK_EE_ID, RTK_EEADDR_LEN1) == 0x8129)
    635 		addr_len = RTK_EEADDR_LEN1;
    636 	else
    637 		addr_len = RTK_EEADDR_LEN0;
    638 
    639 	/*
    640 	 * Get station address.
    641 	 */
    642 	val = rtk_read_eeprom(sc, RTK_EE_EADDR0, addr_len);
    643 	eaddr[0] = val & 0xff;
    644 	eaddr[1] = val >> 8;
    645 	val = rtk_read_eeprom(sc, RTK_EE_EADDR1, addr_len);
    646 	eaddr[2] = val & 0xff;
    647 	eaddr[3] = val >> 8;
    648 	val = rtk_read_eeprom(sc, RTK_EE_EADDR2, addr_len);
    649 	eaddr[4] = val & 0xff;
    650 	eaddr[5] = val >> 8;
    651 
    652 	if ((error = bus_dmamem_alloc(sc->sc_dmat,
    653 	    RTK_RXBUFLEN + 16, PAGE_SIZE, 0, &sc->sc_dmaseg, 1, &sc->sc_dmanseg,
    654 	    BUS_DMA_NOWAIT)) != 0) {
    655 		aprint_error_dev(self,
    656 		    "can't allocate recv buffer, error = %d\n", error);
    657 		goto fail_0;
    658 	}
    659 
    660 	if ((error = bus_dmamem_map(sc->sc_dmat, &sc->sc_dmaseg, sc->sc_dmanseg,
    661 	    RTK_RXBUFLEN + 16, (void **)&sc->rtk_rx_buf,
    662 	    BUS_DMA_NOWAIT|BUS_DMA_COHERENT)) != 0) {
    663 		aprint_error_dev(self,
    664 		    "can't map recv buffer, error = %d\n", error);
    665 		goto fail_1;
    666 	}
    667 
    668 	if ((error = bus_dmamap_create(sc->sc_dmat,
    669 	    RTK_RXBUFLEN + 16, 1, RTK_RXBUFLEN + 16, 0, BUS_DMA_NOWAIT,
    670 	    &sc->recv_dmamap)) != 0) {
    671 		aprint_error_dev(self,
    672 		    "can't create recv buffer DMA map, error = %d\n", error);
    673 		goto fail_2;
    674 	}
    675 
    676 	if ((error = bus_dmamap_load(sc->sc_dmat, sc->recv_dmamap,
    677 	    sc->rtk_rx_buf, RTK_RXBUFLEN + 16,
    678 	    NULL, BUS_DMA_READ|BUS_DMA_NOWAIT)) != 0) {
    679 		aprint_error_dev(self,
    680 		    "can't load recv buffer DMA map, error = %d\n", error);
    681 		goto fail_3;
    682 	}
    683 
    684 	for (i = 0; i < RTK_TX_LIST_CNT; i++) {
    685 		txd = &sc->rtk_tx_descs[i];
    686 		if ((error = bus_dmamap_create(sc->sc_dmat,
    687 		    MCLBYTES, 1, MCLBYTES, 0, BUS_DMA_NOWAIT,
    688 		    &txd->txd_dmamap)) != 0) {
    689 			aprint_error_dev(self,
    690 			    "can't create snd buffer DMA map, error = %d\n",
    691 			    error);
    692 			goto fail_4;
    693 		}
    694 		txd->txd_txaddr = RTK_TXADDR0 + (i * 4);
    695 		txd->txd_txstat = RTK_TXSTAT0 + (i * 4);
    696 	}
    697 	SIMPLEQ_INIT(&sc->rtk_tx_free);
    698 	SIMPLEQ_INIT(&sc->rtk_tx_dirty);
    699 
    700 	/*
    701 	 * From this point forward, the attachment cannot fail. A failure
    702 	 * before this releases all resources thar may have been
    703 	 * allocated.
    704 	 */
    705 	sc->sc_flags |= RTK_ATTACHED;
    706 
    707 	/* Reset the adapter. */
    708 	rtk_reset(sc);
    709 
    710 	aprint_normal_dev(self, "Ethernet address %s\n", ether_sprintf(eaddr));
    711 
    712 	ifp = &sc->ethercom.ec_if;
    713 	ifp->if_softc = sc;
    714 	strcpy(ifp->if_xname, device_xname(self));
    715 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
    716 	ifp->if_ioctl = rtk_ioctl;
    717 	ifp->if_start = rtk_start;
    718 	ifp->if_watchdog = rtk_watchdog;
    719 	ifp->if_init = rtk_init;
    720 	ifp->if_stop = rtk_stop;
    721 	IFQ_SET_READY(&ifp->if_snd);
    722 
    723 	/*
    724 	 * Do ifmedia setup.
    725 	 */
    726 	sc->mii.mii_ifp = ifp;
    727 	sc->mii.mii_readreg = rtk_phy_readreg;
    728 	sc->mii.mii_writereg = rtk_phy_writereg;
    729 	sc->mii.mii_statchg = rtk_phy_statchg;
    730 	sc->ethercom.ec_mii = &sc->mii;
    731 	ifmedia_init(&sc->mii.mii_media, IFM_IMASK, ether_mediachange,
    732 	    ether_mediastatus);
    733 	mii_attach(self, &sc->mii, 0xffffffff,
    734 	    MII_PHY_ANY, MII_OFFSET_ANY, 0);
    735 
    736 	/* Choose a default media. */
    737 	if (LIST_FIRST(&sc->mii.mii_phys) == NULL) {
    738 		ifmedia_add(&sc->mii.mii_media, IFM_ETHER|IFM_NONE, 0, NULL);
    739 		ifmedia_set(&sc->mii.mii_media, IFM_ETHER|IFM_NONE);
    740 	} else {
    741 		ifmedia_set(&sc->mii.mii_media, IFM_ETHER|IFM_AUTO);
    742 	}
    743 
    744 	/*
    745 	 * Call MI attach routines.
    746 	 */
    747 	if_attach(ifp);
    748 	ether_ifattach(ifp, eaddr);
    749 
    750 #if NRND > 0
    751 	rnd_attach_source(&sc->rnd_source, device_xname(self),
    752 	    RND_TYPE_NET, 0);
    753 #endif
    754 
    755 	return;
    756  fail_4:
    757 	for (i = 0; i < RTK_TX_LIST_CNT; i++) {
    758 		txd = &sc->rtk_tx_descs[i];
    759 		if (txd->txd_dmamap != NULL)
    760 			bus_dmamap_destroy(sc->sc_dmat, txd->txd_dmamap);
    761 	}
    762  fail_3:
    763 	bus_dmamap_destroy(sc->sc_dmat, sc->recv_dmamap);
    764  fail_2:
    765 	bus_dmamem_unmap(sc->sc_dmat, sc->rtk_rx_buf,
    766 	    RTK_RXBUFLEN + 16);
    767  fail_1:
    768 	bus_dmamem_free(sc->sc_dmat, &sc->sc_dmaseg, sc->sc_dmanseg);
    769  fail_0:
    770 	return;
    771 }
    772 
    773 /*
    774  * Initialize the transmit descriptors.
    775  */
    776 static void
    777 rtk_list_tx_init(struct rtk_softc *sc)
    778 {
    779 	struct rtk_tx_desc *txd;
    780 	int i;
    781 
    782 	while ((txd = SIMPLEQ_FIRST(&sc->rtk_tx_dirty)) != NULL)
    783 		SIMPLEQ_REMOVE_HEAD(&sc->rtk_tx_dirty, txd_q);
    784 	while ((txd = SIMPLEQ_FIRST(&sc->rtk_tx_free)) != NULL)
    785 		SIMPLEQ_REMOVE_HEAD(&sc->rtk_tx_free, txd_q);
    786 
    787 	for (i = 0; i < RTK_TX_LIST_CNT; i++) {
    788 		txd = &sc->rtk_tx_descs[i];
    789 		CSR_WRITE_4(sc, txd->txd_txaddr, 0);
    790 		SIMPLEQ_INSERT_TAIL(&sc->rtk_tx_free, txd, txd_q);
    791 	}
    792 }
    793 
    794 /*
    795  * rtk_activate:
    796  *     Handle device activation/deactivation requests.
    797  */
    798 int
    799 rtk_activate(device_t self, enum devact act)
    800 {
    801 	struct rtk_softc *sc = device_private(self);
    802 	int s, error;
    803 
    804 	error = 0;
    805 	s = splnet();
    806 	switch (act) {
    807 	case DVACT_ACTIVATE:
    808 		error = EOPNOTSUPP;
    809 		break;
    810 	case DVACT_DEACTIVATE:
    811 		mii_activate(&sc->mii, act, MII_PHY_ANY, MII_OFFSET_ANY);
    812 		if_deactivate(&sc->ethercom.ec_if);
    813 		break;
    814 	}
    815 	splx(s);
    816 
    817 	return error;
    818 }
    819 
    820 /*
    821  * rtk_detach:
    822  *     Detach a rtk interface.
    823  */
    824 int
    825 rtk_detach(struct rtk_softc *sc)
    826 {
    827 	struct ifnet *ifp = &sc->ethercom.ec_if;
    828 	struct rtk_tx_desc *txd;
    829 	int i;
    830 
    831 	/*
    832 	 * Succeed now if there isn't any work to do.
    833 	 */
    834 	if ((sc->sc_flags & RTK_ATTACHED) == 0)
    835 		return 0;
    836 
    837 	/* Unhook our tick handler. */
    838 	callout_stop(&sc->rtk_tick_ch);
    839 
    840 	/* Detach all PHYs. */
    841 	mii_detach(&sc->mii, MII_PHY_ANY, MII_OFFSET_ANY);
    842 
    843 	/* Delete all remaining media. */
    844 	ifmedia_delete_instance(&sc->mii.mii_media, IFM_INST_ANY);
    845 
    846 #if NRND > 0
    847 	rnd_detach_source(&sc->rnd_source);
    848 #endif
    849 
    850 	ether_ifdetach(ifp);
    851 	if_detach(ifp);
    852 
    853 	for (i = 0; i < RTK_TX_LIST_CNT; i++) {
    854 		txd = &sc->rtk_tx_descs[i];
    855 		if (txd->txd_dmamap != NULL)
    856 			bus_dmamap_destroy(sc->sc_dmat, txd->txd_dmamap);
    857 	}
    858 	bus_dmamap_destroy(sc->sc_dmat, sc->recv_dmamap);
    859 	bus_dmamem_unmap(sc->sc_dmat, sc->rtk_rx_buf,
    860 	    RTK_RXBUFLEN + 16);
    861 	bus_dmamem_free(sc->sc_dmat, &sc->sc_dmaseg, sc->sc_dmanseg);
    862 
    863 	return 0;
    864 }
    865 
    866 /*
    867  * rtk_enable:
    868  *     Enable the RTL81X9 chip.
    869  */
    870 int
    871 rtk_enable(struct rtk_softc *sc)
    872 {
    873 
    874 	if (RTK_IS_ENABLED(sc) == 0 && sc->sc_enable != NULL) {
    875 		if ((*sc->sc_enable)(sc) != 0) {
    876 			printf("%s: device enable failed\n",
    877 			    device_xname(sc->sc_dev));
    878 			return EIO;
    879 		}
    880 		sc->sc_flags |= RTK_ENABLED;
    881 	}
    882 	return 0;
    883 }
    884 
    885 /*
    886  * rtk_disable:
    887  *     Disable the RTL81X9 chip.
    888  */
    889 void
    890 rtk_disable(struct rtk_softc *sc)
    891 {
    892 
    893 	if (RTK_IS_ENABLED(sc) && sc->sc_disable != NULL) {
    894 		(*sc->sc_disable)(sc);
    895 		sc->sc_flags &= ~RTK_ENABLED;
    896 	}
    897 }
    898 
    899 /*
    900  * A frame has been uploaded: pass the resulting mbuf chain up to
    901  * the higher level protocols.
    902  *
    903  * You know there's something wrong with a PCI bus-master chip design.
    904  *
    905  * The receive operation is badly documented in the datasheet, so I'll
    906  * attempt to document it here. The driver provides a buffer area and
    907  * places its base address in the RX buffer start address register.
    908  * The chip then begins copying frames into the RX buffer. Each frame
    909  * is preceded by a 32-bit RX status word which specifies the length
    910  * of the frame and certain other status bits. Each frame (starting with
    911  * the status word) is also 32-bit aligned. The frame length is in the
    912  * first 16 bits of the status word; the lower 15 bits correspond with
    913  * the 'rx status register' mentioned in the datasheet.
    914  *
    915  * Note: to make the Alpha happy, the frame payload needs to be aligned
    916  * on a 32-bit boundary. To achieve this, we copy the data to mbuf
    917  * shifted forward 2 bytes.
    918  */
    919 static void
    920 rtk_rxeof(struct rtk_softc *sc)
    921 {
    922 	struct mbuf *m;
    923 	struct ifnet *ifp;
    924 	uint8_t *rxbufpos, *dst;
    925 	u_int total_len, wrap;
    926 	uint32_t rxstat;
    927 	uint16_t cur_rx, new_rx;
    928 	uint16_t limit;
    929 	uint16_t rx_bytes, max_bytes;
    930 
    931 	ifp = &sc->ethercom.ec_if;
    932 
    933 	cur_rx = (CSR_READ_2(sc, RTK_CURRXADDR) + 16) % RTK_RXBUFLEN;
    934 
    935 	/* Do not try to read past this point. */
    936 	limit = CSR_READ_2(sc, RTK_CURRXBUF) % RTK_RXBUFLEN;
    937 
    938 	if (limit < cur_rx)
    939 		max_bytes = (RTK_RXBUFLEN - cur_rx) + limit;
    940 	else
    941 		max_bytes = limit - cur_rx;
    942 	rx_bytes = 0;
    943 
    944 	while ((CSR_READ_1(sc, RTK_COMMAND) & RTK_CMD_EMPTY_RXBUF) == 0) {
    945 		rxbufpos = sc->rtk_rx_buf + cur_rx;
    946 		bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap, cur_rx,
    947 		    RTK_RXSTAT_LEN, BUS_DMASYNC_POSTREAD);
    948 		rxstat = le32toh(*(uint32_t *)rxbufpos);
    949 		bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap, cur_rx,
    950 		    RTK_RXSTAT_LEN, BUS_DMASYNC_PREREAD);
    951 
    952 		/*
    953 		 * Here's a totally undocumented fact for you. When the
    954 		 * RealTek chip is in the process of copying a packet into
    955 		 * RAM for you, the length will be 0xfff0. If you spot a
    956 		 * packet header with this value, you need to stop. The
    957 		 * datasheet makes absolutely no mention of this and
    958 		 * RealTek should be shot for this.
    959 		 */
    960 		total_len = rxstat >> 16;
    961 		if (total_len == RTK_RXSTAT_UNFINISHED)
    962 			break;
    963 
    964 		if ((rxstat & RTK_RXSTAT_RXOK) == 0 ||
    965 		    total_len < ETHER_MIN_LEN ||
    966 		    total_len > (MCLBYTES - RTK_ETHER_ALIGN)) {
    967 			ifp->if_ierrors++;
    968 
    969 			/*
    970 			 * submitted by:[netbsd-pcmcia:00484]
    971 			 *	Takahiro Kambe <taca (at) sky.yamashina.kyoto.jp>
    972 			 * obtain from:
    973 			 *     FreeBSD if_rl.c rev 1.24->1.25
    974 			 *
    975 			 */
    976 #if 0
    977 			if (rxstat & (RTK_RXSTAT_BADSYM|RTK_RXSTAT_RUNT|
    978 			    RTK_RXSTAT_GIANT|RTK_RXSTAT_CRCERR|
    979 			    RTK_RXSTAT_ALIGNERR)) {
    980 				CSR_WRITE_2(sc, RTK_COMMAND, RTK_CMD_TX_ENB);
    981 				CSR_WRITE_2(sc, RTK_COMMAND,
    982 				    RTK_CMD_TX_ENB|RTK_CMD_RX_ENB);
    983 				CSR_WRITE_4(sc, RTK_RXCFG, RTK_RXCFG_CONFIG);
    984 				CSR_WRITE_4(sc, RTK_RXADDR,
    985 				    sc->recv_dmamap->dm_segs[0].ds_addr);
    986 				cur_rx = 0;
    987 			}
    988 			break;
    989 #else
    990 			rtk_init(ifp);
    991 			return;
    992 #endif
    993 		}
    994 
    995 		/* No errors; receive the packet. */
    996 		rx_bytes += total_len + RTK_RXSTAT_LEN;
    997 
    998 		/*
    999 		 * Avoid trying to read more bytes than we know
   1000 		 * the chip has prepared for us.
   1001 		 */
   1002 		if (rx_bytes > max_bytes)
   1003 			break;
   1004 
   1005 		/*
   1006 		 * Skip the status word, wrapping around to the beginning
   1007 		 * of the Rx area, if necessary.
   1008 		 */
   1009 		cur_rx = (cur_rx + RTK_RXSTAT_LEN) % RTK_RXBUFLEN;
   1010 		rxbufpos = sc->rtk_rx_buf + cur_rx;
   1011 
   1012 		/*
   1013 		 * Compute the number of bytes at which the packet
   1014 		 * will wrap to the beginning of the ring buffer.
   1015 		 */
   1016 		wrap = RTK_RXBUFLEN - cur_rx;
   1017 
   1018 		/*
   1019 		 * Compute where the next pending packet is.
   1020 		 */
   1021 		if (total_len > wrap)
   1022 			new_rx = total_len - wrap;
   1023 		else
   1024 			new_rx = cur_rx + total_len;
   1025 		/* Round up to 32-bit boundary. */
   1026 		new_rx = roundup2(new_rx, sizeof(uint32_t)) % RTK_RXBUFLEN;
   1027 
   1028 		/*
   1029 		 * The RealTek chip includes the CRC with every
   1030 		 * incoming packet; trim it off here.
   1031 		 */
   1032 		total_len -= ETHER_CRC_LEN;
   1033 
   1034 		/*
   1035 		 * Now allocate an mbuf (and possibly a cluster) to hold
   1036 		 * the packet. Note we offset the packet 2 bytes so that
   1037 		 * data after the Ethernet header will be 4-byte aligned.
   1038 		 */
   1039 		MGETHDR(m, M_DONTWAIT, MT_DATA);
   1040 		if (m == NULL) {
   1041 			printf("%s: unable to allocate Rx mbuf\n",
   1042 			    device_xname(sc->sc_dev));
   1043 			ifp->if_ierrors++;
   1044 			goto next_packet;
   1045 		}
   1046 		if (total_len > (MHLEN - RTK_ETHER_ALIGN)) {
   1047 			MCLGET(m, M_DONTWAIT);
   1048 			if ((m->m_flags & M_EXT) == 0) {
   1049 				printf("%s: unable to allocate Rx cluster\n",
   1050 				    device_xname(sc->sc_dev));
   1051 				ifp->if_ierrors++;
   1052 				m_freem(m);
   1053 				m = NULL;
   1054 				goto next_packet;
   1055 			}
   1056 		}
   1057 		m->m_data += RTK_ETHER_ALIGN;	/* for alignment */
   1058 		m->m_pkthdr.rcvif = ifp;
   1059 		m->m_pkthdr.len = m->m_len = total_len;
   1060 		dst = mtod(m, void *);
   1061 
   1062 		/*
   1063 		 * If the packet wraps, copy up to the wrapping point.
   1064 		 */
   1065 		if (total_len > wrap) {
   1066 			bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap,
   1067 			    cur_rx, wrap, BUS_DMASYNC_POSTREAD);
   1068 			memcpy(dst, rxbufpos, wrap);
   1069 			bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap,
   1070 			    cur_rx, wrap, BUS_DMASYNC_PREREAD);
   1071 			cur_rx = 0;
   1072 			rxbufpos = sc->rtk_rx_buf;
   1073 			total_len -= wrap;
   1074 			dst += wrap;
   1075 		}
   1076 
   1077 		/*
   1078 		 * ...and now the rest.
   1079 		 */
   1080 		bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap,
   1081 		    cur_rx, total_len, BUS_DMASYNC_POSTREAD);
   1082 		memcpy(dst, rxbufpos, total_len);
   1083 		bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap,
   1084 		    cur_rx, total_len, BUS_DMASYNC_PREREAD);
   1085 
   1086  next_packet:
   1087 		CSR_WRITE_2(sc, RTK_CURRXADDR, (new_rx - 16) % RTK_RXBUFLEN);
   1088 		cur_rx = new_rx;
   1089 
   1090 		if (m == NULL)
   1091 			continue;
   1092 
   1093 		ifp->if_ipackets++;
   1094 
   1095 #if NBPFILTER > 0
   1096 		if (ifp->if_bpf)
   1097 			bpf_mtap(ifp->if_bpf, m);
   1098 #endif
   1099 		/* pass it on. */
   1100 		(*ifp->if_input)(ifp, m);
   1101 	}
   1102 }
   1103 
   1104 /*
   1105  * A frame was downloaded to the chip. It's safe for us to clean up
   1106  * the list buffers.
   1107  */
   1108 static void
   1109 rtk_txeof(struct rtk_softc *sc)
   1110 {
   1111 	struct ifnet *ifp;
   1112 	struct rtk_tx_desc *txd;
   1113 	uint32_t txstat;
   1114 
   1115 	ifp = &sc->ethercom.ec_if;
   1116 
   1117 	/*
   1118 	 * Go through our tx list and free mbufs for those
   1119 	 * frames that have been uploaded.
   1120 	 */
   1121 	while ((txd = SIMPLEQ_FIRST(&sc->rtk_tx_dirty)) != NULL) {
   1122 		txstat = CSR_READ_4(sc, txd->txd_txstat);
   1123 		if ((txstat & (RTK_TXSTAT_TX_OK|
   1124 		    RTK_TXSTAT_TX_UNDERRUN|RTK_TXSTAT_TXABRT)) == 0)
   1125 			break;
   1126 
   1127 		SIMPLEQ_REMOVE_HEAD(&sc->rtk_tx_dirty, txd_q);
   1128 
   1129 		bus_dmamap_sync(sc->sc_dmat, txd->txd_dmamap, 0,
   1130 		    txd->txd_dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
   1131 		bus_dmamap_unload(sc->sc_dmat, txd->txd_dmamap);
   1132 		m_freem(txd->txd_mbuf);
   1133 		txd->txd_mbuf = NULL;
   1134 
   1135 		ifp->if_collisions += (txstat & RTK_TXSTAT_COLLCNT) >> 24;
   1136 
   1137 		if (txstat & RTK_TXSTAT_TX_OK)
   1138 			ifp->if_opackets++;
   1139 		else {
   1140 			ifp->if_oerrors++;
   1141 
   1142 			/*
   1143 			 * Increase Early TX threshold if underrun occurred.
   1144 			 * Increase step 64 bytes.
   1145 			 */
   1146 			if (txstat & RTK_TXSTAT_TX_UNDERRUN) {
   1147 #ifdef DEBUG
   1148 				printf("%s: transmit underrun;",
   1149 				    device_xname(sc->sc_dev));
   1150 #endif
   1151 				if (sc->sc_txthresh < RTK_TXTH_MAX) {
   1152 					sc->sc_txthresh += 2;
   1153 #ifdef DEBUG
   1154 					printf(" new threshold: %d bytes",
   1155 					    sc->sc_txthresh * 32);
   1156 #endif
   1157 				}
   1158 #ifdef DEBUG
   1159 				printf("\n");
   1160 #endif
   1161 			}
   1162 			if (txstat & (RTK_TXSTAT_TXABRT|RTK_TXSTAT_OUTOFWIN))
   1163 				CSR_WRITE_4(sc, RTK_TXCFG, RTK_TXCFG_CONFIG);
   1164 		}
   1165 		SIMPLEQ_INSERT_TAIL(&sc->rtk_tx_free, txd, txd_q);
   1166 		ifp->if_flags &= ~IFF_OACTIVE;
   1167 	}
   1168 
   1169 	/* Clear the timeout timer if there is no pending packet. */
   1170 	if (SIMPLEQ_EMPTY(&sc->rtk_tx_dirty))
   1171 		ifp->if_timer = 0;
   1172 
   1173 }
   1174 
   1175 int
   1176 rtk_intr(void *arg)
   1177 {
   1178 	struct rtk_softc *sc;
   1179 	struct ifnet *ifp;
   1180 	uint16_t status;
   1181 	int handled;
   1182 
   1183 	sc = arg;
   1184 	ifp = &sc->ethercom.ec_if;
   1185 
   1186 	if (!device_has_power(sc->sc_dev))
   1187 		return 0;
   1188 
   1189 	/* Disable interrupts. */
   1190 	CSR_WRITE_2(sc, RTK_IMR, 0x0000);
   1191 
   1192 	handled = 0;
   1193 	for (;;) {
   1194 
   1195 		status = CSR_READ_2(sc, RTK_ISR);
   1196 
   1197 		if (status == 0xffff)
   1198 			break; /* Card is gone... */
   1199 
   1200 		if (status)
   1201 			CSR_WRITE_2(sc, RTK_ISR, status);
   1202 
   1203 		if ((status & RTK_INTRS) == 0)
   1204 			break;
   1205 
   1206 		handled = 1;
   1207 
   1208 		if (status & RTK_ISR_RX_OK)
   1209 			rtk_rxeof(sc);
   1210 
   1211 		if (status & RTK_ISR_RX_ERR)
   1212 			rtk_rxeof(sc);
   1213 
   1214 		if (status & (RTK_ISR_TX_OK|RTK_ISR_TX_ERR))
   1215 			rtk_txeof(sc);
   1216 
   1217 		if (status & RTK_ISR_SYSTEM_ERR) {
   1218 			rtk_reset(sc);
   1219 			rtk_init(ifp);
   1220 		}
   1221 	}
   1222 
   1223 	/* Re-enable interrupts. */
   1224 	CSR_WRITE_2(sc, RTK_IMR, RTK_INTRS);
   1225 
   1226 	if (IFQ_IS_EMPTY(&ifp->if_snd) == 0)
   1227 		rtk_start(ifp);
   1228 
   1229 #if NRND > 0
   1230 	if (RND_ENABLED(&sc->rnd_source))
   1231 		rnd_add_uint32(&sc->rnd_source, status);
   1232 #endif
   1233 
   1234 	return handled;
   1235 }
   1236 
   1237 /*
   1238  * Main transmit routine.
   1239  */
   1240 
   1241 static void
   1242 rtk_start(struct ifnet *ifp)
   1243 {
   1244 	struct rtk_softc *sc;
   1245 	struct rtk_tx_desc *txd;
   1246 	struct mbuf *m_head, *m_new;
   1247 	int error, len;
   1248 
   1249 	sc = ifp->if_softc;
   1250 
   1251 	while ((txd = SIMPLEQ_FIRST(&sc->rtk_tx_free)) != NULL) {
   1252 		IFQ_POLL(&ifp->if_snd, m_head);
   1253 		if (m_head == NULL)
   1254 			break;
   1255 		m_new = NULL;
   1256 
   1257 		/*
   1258 		 * Load the DMA map.  If this fails, the packet didn't
   1259 		 * fit in one DMA segment, and we need to copy.  Note,
   1260 		 * the packet must also be aligned.
   1261 		 * if the packet is too small, copy it too, so we're sure
   1262 		 * so have enouth room for the pad buffer.
   1263 		 */
   1264 		if ((mtod(m_head, uintptr_t) & 3) != 0 ||
   1265 		    m_head->m_pkthdr.len < ETHER_PAD_LEN ||
   1266 		    bus_dmamap_load_mbuf(sc->sc_dmat, txd->txd_dmamap,
   1267 			m_head, BUS_DMA_WRITE|BUS_DMA_NOWAIT) != 0) {
   1268 			MGETHDR(m_new, M_DONTWAIT, MT_DATA);
   1269 			if (m_new == NULL) {
   1270 				printf("%s: unable to allocate Tx mbuf\n",
   1271 				    device_xname(sc->sc_dev));
   1272 				break;
   1273 			}
   1274 			if (m_head->m_pkthdr.len > MHLEN) {
   1275 				MCLGET(m_new, M_DONTWAIT);
   1276 				if ((m_new->m_flags & M_EXT) == 0) {
   1277 					printf("%s: unable to allocate Tx "
   1278 					    "cluster\n",
   1279 					    device_xname(sc->sc_dev));
   1280 					m_freem(m_new);
   1281 					break;
   1282 				}
   1283 			}
   1284 			m_copydata(m_head, 0, m_head->m_pkthdr.len,
   1285 			    mtod(m_new, void *));
   1286 			m_new->m_pkthdr.len = m_new->m_len =
   1287 			    m_head->m_pkthdr.len;
   1288 			if (m_head->m_pkthdr.len < ETHER_PAD_LEN) {
   1289 				memset(
   1290 				    mtod(m_new, char *) + m_head->m_pkthdr.len,
   1291 				    0, ETHER_PAD_LEN - m_head->m_pkthdr.len);
   1292 				m_new->m_pkthdr.len = m_new->m_len =
   1293 				    ETHER_PAD_LEN;
   1294 			}
   1295 			error = bus_dmamap_load_mbuf(sc->sc_dmat,
   1296 			    txd->txd_dmamap, m_new,
   1297 			    BUS_DMA_WRITE|BUS_DMA_NOWAIT);
   1298 			if (error) {
   1299 				printf("%s: unable to load Tx buffer, "
   1300 				    "error = %d\n",
   1301 				    device_xname(sc->sc_dev), error);
   1302 				break;
   1303 			}
   1304 		}
   1305 		IFQ_DEQUEUE(&ifp->if_snd, m_head);
   1306 #if NBPFILTER > 0
   1307 		/*
   1308 		 * If there's a BPF listener, bounce a copy of this frame
   1309 		 * to him.
   1310 		 */
   1311 		if (ifp->if_bpf)
   1312 			bpf_mtap(ifp->if_bpf, m_head);
   1313 #endif
   1314 		if (m_new != NULL) {
   1315 			m_freem(m_head);
   1316 			m_head = m_new;
   1317 		}
   1318 		txd->txd_mbuf = m_head;
   1319 
   1320 		SIMPLEQ_REMOVE_HEAD(&sc->rtk_tx_free, txd_q);
   1321 		SIMPLEQ_INSERT_TAIL(&sc->rtk_tx_dirty, txd, txd_q);
   1322 
   1323 		/*
   1324 		 * Transmit the frame.
   1325 		 */
   1326 		bus_dmamap_sync(sc->sc_dmat,
   1327 		    txd->txd_dmamap, 0, txd->txd_dmamap->dm_mapsize,
   1328 		    BUS_DMASYNC_PREWRITE);
   1329 
   1330 		len = txd->txd_dmamap->dm_segs[0].ds_len;
   1331 
   1332 		CSR_WRITE_4(sc, txd->txd_txaddr,
   1333 		    txd->txd_dmamap->dm_segs[0].ds_addr);
   1334 		CSR_WRITE_4(sc, txd->txd_txstat,
   1335 		    RTK_TXSTAT_THRESH(sc->sc_txthresh) | len);
   1336 
   1337 		/*
   1338 		 * Set a timeout in case the chip goes out to lunch.
   1339 		 */
   1340 		ifp->if_timer = 5;
   1341 	}
   1342 
   1343 	/*
   1344 	 * We broke out of the loop because all our TX slots are
   1345 	 * full. Mark the NIC as busy until it drains some of the
   1346 	 * packets from the queue.
   1347 	 */
   1348 	if (SIMPLEQ_EMPTY(&sc->rtk_tx_free))
   1349 		ifp->if_flags |= IFF_OACTIVE;
   1350 }
   1351 
   1352 static int
   1353 rtk_init(struct ifnet *ifp)
   1354 {
   1355 	struct rtk_softc *sc = ifp->if_softc;
   1356 	int error, i;
   1357 	uint32_t rxcfg;
   1358 
   1359 	if ((error = rtk_enable(sc)) != 0)
   1360 		goto out;
   1361 
   1362 	/*
   1363 	 * Cancel pending I/O.
   1364 	 */
   1365 	rtk_stop(ifp, 0);
   1366 
   1367 	/* Init our MAC address */
   1368 	for (i = 0; i < ETHER_ADDR_LEN; i++) {
   1369 		CSR_WRITE_1(sc, RTK_IDR0 + i, CLLADDR(ifp->if_sadl)[i]);
   1370 	}
   1371 
   1372 	/* Init the RX buffer pointer register. */
   1373 	bus_dmamap_sync(sc->sc_dmat, sc->recv_dmamap, 0,
   1374 	    sc->recv_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
   1375 	CSR_WRITE_4(sc, RTK_RXADDR, sc->recv_dmamap->dm_segs[0].ds_addr);
   1376 
   1377 	/* Init TX descriptors. */
   1378 	rtk_list_tx_init(sc);
   1379 
   1380 	/* Init Early TX threshold. */
   1381 	sc->sc_txthresh = RTK_TXTH_256;
   1382 	/*
   1383 	 * Enable transmit and receive.
   1384 	 */
   1385 	CSR_WRITE_1(sc, RTK_COMMAND, RTK_CMD_TX_ENB|RTK_CMD_RX_ENB);
   1386 
   1387 	/*
   1388 	 * Set the initial TX and RX configuration.
   1389 	 */
   1390 	CSR_WRITE_4(sc, RTK_TXCFG, RTK_TXCFG_CONFIG);
   1391 	CSR_WRITE_4(sc, RTK_RXCFG, RTK_RXCFG_CONFIG);
   1392 
   1393 	/* Set the individual bit to receive frames for this host only. */
   1394 	rxcfg = CSR_READ_4(sc, RTK_RXCFG);
   1395 	rxcfg |= RTK_RXCFG_RX_INDIV;
   1396 
   1397 	/* If we want promiscuous mode, set the allframes bit. */
   1398 	if (ifp->if_flags & IFF_PROMISC) {
   1399 		rxcfg |= RTK_RXCFG_RX_ALLPHYS;
   1400 		CSR_WRITE_4(sc, RTK_RXCFG, rxcfg);
   1401 	} else {
   1402 		rxcfg &= ~RTK_RXCFG_RX_ALLPHYS;
   1403 		CSR_WRITE_4(sc, RTK_RXCFG, rxcfg);
   1404 	}
   1405 
   1406 	/*
   1407 	 * Set capture broadcast bit to capture broadcast frames.
   1408 	 */
   1409 	if (ifp->if_flags & IFF_BROADCAST) {
   1410 		rxcfg |= RTK_RXCFG_RX_BROAD;
   1411 		CSR_WRITE_4(sc, RTK_RXCFG, rxcfg);
   1412 	} else {
   1413 		rxcfg &= ~RTK_RXCFG_RX_BROAD;
   1414 		CSR_WRITE_4(sc, RTK_RXCFG, rxcfg);
   1415 	}
   1416 
   1417 	/*
   1418 	 * Program the multicast filter, if necessary.
   1419 	 */
   1420 	rtk_setmulti(sc);
   1421 
   1422 	/*
   1423 	 * Enable interrupts.
   1424 	 */
   1425 	CSR_WRITE_2(sc, RTK_IMR, RTK_INTRS);
   1426 
   1427 	/* Start RX/TX process. */
   1428 	CSR_WRITE_4(sc, RTK_MISSEDPKT, 0);
   1429 
   1430 	/* Enable receiver and transmitter. */
   1431 	CSR_WRITE_1(sc, RTK_COMMAND, RTK_CMD_TX_ENB|RTK_CMD_RX_ENB);
   1432 
   1433 	CSR_WRITE_1(sc, RTK_CFG1, RTK_CFG1_DRVLOAD|RTK_CFG1_FULLDUPLEX);
   1434 
   1435 	/*
   1436 	 * Set current media.
   1437 	 */
   1438 	if ((error = ether_mediachange(ifp)) != 0)
   1439 		goto out;
   1440 
   1441 	ifp->if_flags |= IFF_RUNNING;
   1442 	ifp->if_flags &= ~IFF_OACTIVE;
   1443 
   1444 	callout_reset(&sc->rtk_tick_ch, hz, rtk_tick, sc);
   1445 
   1446  out:
   1447 	if (error) {
   1448 		ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
   1449 		ifp->if_timer = 0;
   1450 		printf("%s: interface not running\n", device_xname(sc->sc_dev));
   1451 	}
   1452 	return error;
   1453 }
   1454 
   1455 static int
   1456 rtk_ioctl(struct ifnet *ifp, u_long command, void *data)
   1457 {
   1458 	struct rtk_softc *sc = ifp->if_softc;
   1459 	int s, error;
   1460 
   1461 	s = splnet();
   1462 	error = ether_ioctl(ifp, command, data);
   1463 	if (error == ENETRESET) {
   1464 		if (ifp->if_flags & IFF_RUNNING) {
   1465 			/*
   1466 			 * Multicast list has changed.  Set the
   1467 			 * hardware filter accordingly.
   1468 			 */
   1469 			rtk_setmulti(sc);
   1470 		}
   1471 		error = 0;
   1472 	}
   1473 	splx(s);
   1474 
   1475 	return error;
   1476 }
   1477 
   1478 static void
   1479 rtk_watchdog(struct ifnet *ifp)
   1480 {
   1481 	struct rtk_softc *sc;
   1482 
   1483 	sc = ifp->if_softc;
   1484 
   1485 	printf("%s: watchdog timeout\n", device_xname(sc->sc_dev));
   1486 	ifp->if_oerrors++;
   1487 	rtk_txeof(sc);
   1488 	rtk_rxeof(sc);
   1489 	rtk_init(ifp);
   1490 }
   1491 
   1492 /*
   1493  * Stop the adapter and free any mbufs allocated to the
   1494  * RX and TX lists.
   1495  */
   1496 static void
   1497 rtk_stop(struct ifnet *ifp, int disable)
   1498 {
   1499 	struct rtk_softc *sc = ifp->if_softc;
   1500 	struct rtk_tx_desc *txd;
   1501 
   1502 	callout_stop(&sc->rtk_tick_ch);
   1503 
   1504 	mii_down(&sc->mii);
   1505 
   1506 	CSR_WRITE_1(sc, RTK_COMMAND, 0x00);
   1507 	CSR_WRITE_2(sc, RTK_IMR, 0x0000);
   1508 
   1509 	/*
   1510 	 * Free the TX list buffers.
   1511 	 */
   1512 	while ((txd = SIMPLEQ_FIRST(&sc->rtk_tx_dirty)) != NULL) {
   1513 		SIMPLEQ_REMOVE_HEAD(&sc->rtk_tx_dirty, txd_q);
   1514 		bus_dmamap_unload(sc->sc_dmat, txd->txd_dmamap);
   1515 		m_freem(txd->txd_mbuf);
   1516 		txd->txd_mbuf = NULL;
   1517 		CSR_WRITE_4(sc, txd->txd_txaddr, 0);
   1518 	}
   1519 
   1520 	if (disable)
   1521 		rtk_disable(sc);
   1522 
   1523 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
   1524 	ifp->if_timer = 0;
   1525 }
   1526 
   1527 static void
   1528 rtk_tick(void *arg)
   1529 {
   1530 	struct rtk_softc *sc = arg;
   1531 	int s;
   1532 
   1533 	s = splnet();
   1534 	mii_tick(&sc->mii);
   1535 	splx(s);
   1536 
   1537 	callout_reset(&sc->rtk_tick_ch, hz, rtk_tick, sc);
   1538 }
   1539