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if_mec.c revision 1.29
      1 /* $NetBSD: if_mec.c,v 1.29 2008/08/14 03:43:50 tsutsui Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2004 Izumi Tsutsui.  All rights reserved.
      5  *
      6  * Redistribution and use in source and binary forms, with or without
      7  * modification, are permitted provided that the following conditions
      8  * are met:
      9  * 1. Redistributions of source code must retain the above copyright
     10  *    notice, this list of conditions and the following disclaimer.
     11  * 2. Redistributions in binary form must reproduce the above copyright
     12  *    notice, this list of conditions and the following disclaimer in the
     13  *    documentation and/or other materials provided with the distribution.
     14  *
     15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     25  */
     26 
     27 /*
     28  * Copyright (c) 2003 Christopher SEKIYA
     29  * All rights reserved.
     30  *
     31  * Redistribution and use in source and binary forms, with or without
     32  * modification, are permitted provided that the following conditions
     33  * are met:
     34  * 1. Redistributions of source code must retain the above copyright
     35  *    notice, this list of conditions and the following disclaimer.
     36  * 2. Redistributions in binary form must reproduce the above copyright
     37  *    notice, this list of conditions and the following disclaimer in the
     38  *    documentation and/or other materials provided with the distribution.
     39  * 3. All advertising materials mentioning features or use of this software
     40  *    must display the following acknowledgement:
     41  *          This product includes software developed for the
     42  *          NetBSD Project.  See http://www.NetBSD.org/ for
     43  *          information about NetBSD.
     44  * 4. The name of the author may not be used to endorse or promote products
     45  *    derived from this software without specific prior written permission.
     46  *
     47  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     48  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     49  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     50  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     51  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     52  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     53  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     54  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     55  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     56  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     57  */
     58 
     59 /*
     60  * MACE MAC-110 Ethernet driver
     61  */
     62 
     63 #include <sys/cdefs.h>
     64 __KERNEL_RCSID(0, "$NetBSD: if_mec.c,v 1.29 2008/08/14 03:43:50 tsutsui Exp $");
     65 
     66 #include "opt_ddb.h"
     67 #include "bpfilter.h"
     68 #include "rnd.h"
     69 
     70 #include <sys/param.h>
     71 #include <sys/systm.h>
     72 #include <sys/device.h>
     73 #include <sys/callout.h>
     74 #include <sys/mbuf.h>
     75 #include <sys/malloc.h>
     76 #include <sys/kernel.h>
     77 #include <sys/socket.h>
     78 #include <sys/ioctl.h>
     79 #include <sys/errno.h>
     80 
     81 #if NRND > 0
     82 #include <sys/rnd.h>
     83 #endif
     84 
     85 #include <net/if.h>
     86 #include <net/if_dl.h>
     87 #include <net/if_media.h>
     88 #include <net/if_ether.h>
     89 
     90 #if NBPFILTER > 0
     91 #include <net/bpf.h>
     92 #endif
     93 
     94 #include <machine/bus.h>
     95 #include <machine/intr.h>
     96 #include <machine/machtype.h>
     97 
     98 #include <dev/mii/mii.h>
     99 #include <dev/mii/miivar.h>
    100 
    101 #include <sgimips/mace/macevar.h>
    102 #include <sgimips/mace/if_mecreg.h>
    103 
    104 #include <dev/arcbios/arcbios.h>
    105 #include <dev/arcbios/arcbiosvar.h>
    106 
    107 /* #define MEC_DEBUG */
    108 
    109 #ifdef MEC_DEBUG
    110 #define MEC_DEBUG_RESET		0x01
    111 #define MEC_DEBUG_START		0x02
    112 #define MEC_DEBUG_STOP		0x04
    113 #define MEC_DEBUG_INTR		0x08
    114 #define MEC_DEBUG_RXINTR	0x10
    115 #define MEC_DEBUG_TXINTR	0x20
    116 uint32_t mec_debug = 0;
    117 #define DPRINTF(x, y)	if (mec_debug & (x)) printf y
    118 #else
    119 #define DPRINTF(x, y)	/* nothing */
    120 #endif
    121 
    122 /*
    123  * Transmit descriptor list size
    124  */
    125 #define MEC_NTXDESC		64
    126 #define MEC_NTXDESC_MASK	(MEC_NTXDESC - 1)
    127 #define MEC_NEXTTX(x)		(((x) + 1) & MEC_NTXDESC_MASK)
    128 #define MEC_NTXDESC_RSVD	4
    129 #define MEC_NTXDESC_INTR	8
    130 
    131 /*
    132  * software state for TX
    133  */
    134 struct mec_txsoft {
    135 	struct mbuf *txs_mbuf;		/* head of our mbuf chain */
    136 	bus_dmamap_t txs_dmamap;	/* our DMA map */
    137 	uint32_t txs_flags;
    138 #define MEC_TXS_BUFLEN_MASK	0x0000007f	/* data len in txd_buf */
    139 #define MEC_TXS_TXDBUF		0x00000080	/* txd_buf is used */
    140 #define MEC_TXS_TXDPTR1		0x00000100	/* txd_ptr[0] is used */
    141 };
    142 
    143 /*
    144  * Transmit buffer descriptor
    145  */
    146 #define MEC_TXDESCSIZE		128
    147 #define MEC_NTXPTR		3
    148 #define MEC_TXD_BUFOFFSET	\
    149 	(sizeof(uint64_t) + MEC_NTXPTR * sizeof(uint64_t))
    150 #define MEC_TXD_BUFSIZE		(MEC_TXDESCSIZE - MEC_TXD_BUFOFFSET)
    151 #define MEC_TXD_BUFSTART(len)	(MEC_TXD_BUFSIZE - (len))
    152 #define MEC_TXD_ALIGN		8
    153 #define MEC_TXD_ROUNDUP(addr)	\
    154 	(((addr) + (MEC_TXD_ALIGN - 1)) & ~((uint64_t)MEC_TXD_ALIGN - 1))
    155 
    156 struct mec_txdesc {
    157 	volatile uint64_t txd_cmd;
    158 #define MEC_TXCMD_DATALEN	0x000000000000ffff	/* data length */
    159 #define MEC_TXCMD_BUFSTART	0x00000000007f0000	/* start byte offset */
    160 #define  TXCMD_BUFSTART(x)	((x) << 16)
    161 #define MEC_TXCMD_TERMDMA	0x0000000000800000	/* stop DMA on abort */
    162 #define MEC_TXCMD_TXINT		0x0000000001000000	/* INT after TX done */
    163 #define MEC_TXCMD_PTR1		0x0000000002000000	/* valid 1st txd_ptr */
    164 #define MEC_TXCMD_PTR2		0x0000000004000000	/* valid 2nd txd_ptr */
    165 #define MEC_TXCMD_PTR3		0x0000000008000000	/* valid 3rd txd_ptr */
    166 #define MEC_TXCMD_UNUSED	0xfffffffff0000000ULL	/* should be zero */
    167 
    168 #define txd_stat	txd_cmd
    169 #define MEC_TXSTAT_LEN		0x000000000000ffff	/* TX length */
    170 #define MEC_TXSTAT_COLCNT	0x00000000000f0000	/* collision count */
    171 #define MEC_TXSTAT_COLCNT_SHIFT	16
    172 #define MEC_TXSTAT_LATE_COL	0x0000000000100000	/* late collision */
    173 #define MEC_TXSTAT_CRCERROR	0x0000000000200000	/* */
    174 #define MEC_TXSTAT_DEFERRED	0x0000000000400000	/* */
    175 #define MEC_TXSTAT_SUCCESS	0x0000000000800000	/* TX complete */
    176 #define MEC_TXSTAT_TOOBIG	0x0000000001000000	/* */
    177 #define MEC_TXSTAT_UNDERRUN	0x0000000002000000	/* */
    178 #define MEC_TXSTAT_COLLISIONS	0x0000000004000000	/* */
    179 #define MEC_TXSTAT_EXDEFERRAL	0x0000000008000000	/* */
    180 #define MEC_TXSTAT_COLLIDED	0x0000000010000000	/* */
    181 #define MEC_TXSTAT_UNUSED	0x7fffffffe0000000ULL	/* should be zero */
    182 #define MEC_TXSTAT_SENT		0x8000000000000000ULL	/* packet sent */
    183 
    184 	uint64_t txd_ptr[MEC_NTXPTR];
    185 #define MEC_TXPTR_UNUSED2	0x0000000000000007	/* should be zero */
    186 #define MEC_TXPTR_DMAADDR	0x00000000fffffff8	/* TX DMA address */
    187 #define MEC_TXPTR_LEN		0x0000ffff00000000ULL	/* buffer length */
    188 #define  TXPTR_LEN(x)		((uint64_t)(x) << 32)
    189 #define MEC_TXPTR_UNUSED1	0xffff000000000000ULL	/* should be zero */
    190 
    191 	uint8_t txd_buf[MEC_TXD_BUFSIZE];
    192 };
    193 
    194 /*
    195  * Receive buffer size
    196  */
    197 #define MEC_NRXDESC		16
    198 #define MEC_NRXDESC_MASK	(MEC_NRXDESC - 1)
    199 #define MEC_NEXTRX(x)		(((x) + 1) & MEC_NRXDESC_MASK)
    200 
    201 /*
    202  * Receive buffer description
    203  */
    204 #define MEC_RXDESCSIZE		4096	/* umm, should be 4kbyte aligned */
    205 #define MEC_RXD_NRXPAD		3
    206 #define MEC_RXD_DMAOFFSET	(1 + MEC_RXD_NRXPAD)
    207 #define MEC_RXD_BUFOFFSET	(MEC_RXD_DMAOFFSET * sizeof(uint64_t))
    208 #define MEC_RXD_BUFSIZE		(MEC_RXDESCSIZE - MEC_RXD_BUFOFFSET)
    209 
    210 struct mec_rxdesc {
    211 	volatile uint64_t rxd_stat;
    212 #define MEC_RXSTAT_LEN		0x000000000000ffff	/* data length */
    213 #define MEC_RXSTAT_VIOLATION	0x0000000000010000	/* code violation (?) */
    214 #define MEC_RXSTAT_UNUSED2	0x0000000000020000	/* unknown (?) */
    215 #define MEC_RXSTAT_CRCERROR	0x0000000000040000	/* CRC error */
    216 #define MEC_RXSTAT_MULTICAST	0x0000000000080000	/* multicast packet */
    217 #define MEC_RXSTAT_BROADCAST	0x0000000000100000	/* broadcast packet */
    218 #define MEC_RXSTAT_INVALID	0x0000000000200000	/* invalid preamble */
    219 #define MEC_RXSTAT_LONGEVENT	0x0000000000400000	/* long packet */
    220 #define MEC_RXSTAT_BADPACKET	0x0000000000800000	/* bad packet */
    221 #define MEC_RXSTAT_CAREVENT	0x0000000001000000	/* carrier event */
    222 #define MEC_RXSTAT_MATCHMCAST	0x0000000002000000	/* match multicast */
    223 #define MEC_RXSTAT_MATCHMAC	0x0000000004000000	/* match MAC */
    224 #define MEC_RXSTAT_SEQNUM	0x00000000f8000000	/* sequence number */
    225 #define MEC_RXSTAT_CKSUM	0x0000ffff00000000ULL	/* IP checksum */
    226 #define MEC_RXSTAT_UNUSED1	0x7fff000000000000ULL	/* should be zero */
    227 #define MEC_RXSTAT_RECEIVED	0x8000000000000000ULL	/* set to 1 on RX */
    228 	uint64_t rxd_pad1[MEC_RXD_NRXPAD];
    229 	uint8_t  rxd_buf[MEC_RXD_BUFSIZE];
    230 };
    231 
    232 /*
    233  * control structures for DMA ops
    234  */
    235 struct mec_control_data {
    236 	/*
    237 	 * TX descriptors and buffers
    238 	 */
    239 	struct mec_txdesc mcd_txdesc[MEC_NTXDESC];
    240 
    241 	/*
    242 	 * RX descriptors and buffers
    243 	 */
    244 	struct mec_rxdesc mcd_rxdesc[MEC_NRXDESC];
    245 };
    246 
    247 /*
    248  * It _seems_ there are some restrictions on descriptor address:
    249  *
    250  * - Base address of txdescs should be 8kbyte aligned
    251  * - Each txdesc should be 128byte aligned
    252  * - Each rxdesc should be 4kbyte aligned
    253  *
    254  * So we should specify 8k align to allocalte txdescs.
    255  * In this case, sizeof(struct mec_txdesc) * MEC_NTXDESC is 8192
    256  * so rxdescs are also allocated at 4kbyte aligned.
    257  */
    258 #define MEC_CONTROL_DATA_ALIGN	(8 * 1024)
    259 
    260 #define MEC_CDOFF(x)	offsetof(struct mec_control_data, x)
    261 #define MEC_CDTXOFF(x)	MEC_CDOFF(mcd_txdesc[(x)])
    262 #define MEC_CDRXOFF(x)	MEC_CDOFF(mcd_rxdesc[(x)])
    263 
    264 /*
    265  * software state per device
    266  */
    267 struct mec_softc {
    268 	device_t sc_dev;		/* generic device structures */
    269 
    270 	bus_space_tag_t sc_st;		/* bus_space tag */
    271 	bus_space_handle_t sc_sh;	/* bus_space handle */
    272 	bus_dma_tag_t sc_dmat;		/* bus_dma tag */
    273 	void *sc_sdhook;		/* shutdown hook */
    274 
    275 	struct ethercom sc_ethercom;	/* Ethernet common part */
    276 
    277 	struct mii_data sc_mii;		/* MII/media information */
    278 	int sc_phyaddr;			/* MII address */
    279 	struct callout sc_tick_ch;	/* tick callout */
    280 
    281 	uint8_t sc_enaddr[ETHER_ADDR_LEN]; /* MAC address */
    282 
    283 	bus_dmamap_t sc_cddmamap;	/* bus_dma map for control data */
    284 #define sc_cddma	sc_cddmamap->dm_segs[0].ds_addr
    285 
    286 	/* pointer to allocated control data */
    287 	struct mec_control_data *sc_control_data;
    288 #define sc_txdesc	sc_control_data->mcd_txdesc
    289 #define sc_rxdesc	sc_control_data->mcd_rxdesc
    290 
    291 	/* software state for TX descs */
    292 	struct mec_txsoft sc_txsoft[MEC_NTXDESC];
    293 
    294 	int sc_txpending;		/* number of TX requests pending */
    295 	int sc_txdirty;			/* first dirty TX descriptor */
    296 	int sc_txlast;			/* last used TX descriptor */
    297 
    298 	int sc_rxptr;			/* next ready RX buffer */
    299 
    300 #if NRND > 0
    301 	rndsource_element_t sc_rnd_source; /* random source */
    302 #endif
    303 };
    304 
    305 #define MEC_CDTXADDR(sc, x)	((sc)->sc_cddma + MEC_CDTXOFF(x))
    306 #define MEC_CDRXADDR(sc, x)	((sc)->sc_cddma + MEC_CDRXOFF(x))
    307 
    308 #define MEC_TXDESCSYNC(sc, x, ops)					\
    309 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
    310 	    MEC_CDTXOFF(x), MEC_TXDESCSIZE, (ops))
    311 #define MEC_TXCMDSYNC(sc, x, ops)					\
    312 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
    313 	    MEC_CDTXOFF(x), sizeof(uint64_t), (ops))
    314 
    315 #define MEC_RXSTATSYNC(sc, x, ops)					\
    316 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
    317 	    MEC_CDRXOFF(x), sizeof(uint64_t), (ops))
    318 #define MEC_RXBUFSYNC(sc, x, len, ops)					\
    319 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
    320 	    MEC_CDRXOFF(x) + MEC_RXD_BUFOFFSET,				\
    321 	    MEC_ETHER_ALIGN + (len), (ops))
    322 
    323 /* XXX these values should be moved to <net/if_ether.h> ? */
    324 #define ETHER_PAD_LEN	(ETHER_MIN_LEN - ETHER_CRC_LEN)
    325 #define MEC_ETHER_ALIGN	2
    326 
    327 static int	mec_match(device_t, cfdata_t, void *);
    328 static void	mec_attach(device_t, device_t, void *);
    329 
    330 static int	mec_mii_readreg(device_t, int, int);
    331 static void	mec_mii_writereg(device_t, int, int, int);
    332 static int	mec_mii_wait(struct mec_softc *);
    333 static void	mec_statchg(device_t);
    334 
    335 static void	enaddr_aton(const char *, uint8_t *);
    336 
    337 static int	mec_init(struct ifnet * ifp);
    338 static void	mec_start(struct ifnet *);
    339 static void	mec_watchdog(struct ifnet *);
    340 static void	mec_tick(void *);
    341 static int	mec_ioctl(struct ifnet *, u_long, void *);
    342 static void	mec_reset(struct mec_softc *);
    343 static void	mec_setfilter(struct mec_softc *);
    344 static int	mec_intr(void *arg);
    345 static void	mec_stop(struct ifnet *, int);
    346 static void	mec_rxintr(struct mec_softc *);
    347 static void	mec_txintr(struct mec_softc *, uint32_t);
    348 static void	mec_shutdown(void *);
    349 
    350 CFATTACH_DECL_NEW(mec, sizeof(struct mec_softc),
    351     mec_match, mec_attach, NULL, NULL);
    352 
    353 static int mec_matched = 0;
    354 
    355 static int
    356 mec_match(device_t parent, cfdata_t cf, void *aux)
    357 {
    358 
    359 	/* allow only one device */
    360 	if (mec_matched)
    361 		return 0;
    362 
    363 	mec_matched = 1;
    364 	return 1;
    365 }
    366 
    367 static void
    368 mec_attach(device_t parent, device_t self, void *aux)
    369 {
    370 	struct mec_softc *sc = device_private(self);
    371 	struct mace_attach_args *maa = aux;
    372 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
    373 	uint64_t address, command;
    374 	const char *macaddr;
    375 	struct mii_softc *child;
    376 	bus_dma_segment_t seg;
    377 	int i, err, rseg;
    378 	bool mac_is_fake;
    379 
    380 	sc->sc_dev = self;
    381 	sc->sc_st = maa->maa_st;
    382 	if (bus_space_subregion(sc->sc_st, maa->maa_sh,
    383 	    maa->maa_offset, 0,	&sc->sc_sh) != 0) {
    384 		aprint_error(": can't map i/o space\n");
    385 		return;
    386 	}
    387 
    388 	/* set up DMA structures */
    389 	sc->sc_dmat = maa->maa_dmat;
    390 
    391 	/*
    392 	 * Allocate the control data structures, and create and load the
    393 	 * DMA map for it.
    394 	 */
    395 	if ((err = bus_dmamem_alloc(sc->sc_dmat,
    396 	    sizeof(struct mec_control_data), MEC_CONTROL_DATA_ALIGN, 0,
    397 	    &seg, 1, &rseg, BUS_DMA_NOWAIT)) != 0) {
    398 		aprint_error(": unable to allocate control data, error = %d\n",
    399 		    err);
    400 		goto fail_0;
    401 	}
    402 	/*
    403 	 * XXX needs re-think...
    404 	 * control data structures contain whole RX data buffer, so
    405 	 * BUS_DMA_COHERENT (which disables cache) may cause some performance
    406 	 * issue on copying data from the RX buffer to mbuf on normal memory,
    407 	 * though we have to make sure all bus_dmamap_sync(9) ops are called
    408 	 * properly in that case.
    409 	 */
    410 	if ((err = bus_dmamem_map(sc->sc_dmat, &seg, rseg,
    411 	    sizeof(struct mec_control_data),
    412 	    (void **)&sc->sc_control_data, /*BUS_DMA_COHERENT*/ 0)) != 0) {
    413 		aprint_error(": unable to map control data, error = %d\n", err);
    414 		goto fail_1;
    415 	}
    416 	memset(sc->sc_control_data, 0, sizeof(struct mec_control_data));
    417 
    418 	if ((err = bus_dmamap_create(sc->sc_dmat,
    419 	    sizeof(struct mec_control_data), 1,
    420 	    sizeof(struct mec_control_data), 0, 0, &sc->sc_cddmamap)) != 0) {
    421 		aprint_error(": unable to create control data DMA map,"
    422 		    " error = %d\n", err);
    423 		goto fail_2;
    424 	}
    425 	if ((err = bus_dmamap_load(sc->sc_dmat, sc->sc_cddmamap,
    426 	    sc->sc_control_data, sizeof(struct mec_control_data), NULL,
    427 	    BUS_DMA_NOWAIT)) != 0) {
    428 		aprint_error(": unable to load control data DMA map,"
    429 		    " error = %d\n", err);
    430 		goto fail_3;
    431 	}
    432 
    433 	/* create TX buffer DMA maps */
    434 	for (i = 0; i < MEC_NTXDESC; i++) {
    435 		if ((err = bus_dmamap_create(sc->sc_dmat,
    436 		    MCLBYTES, 1, MCLBYTES, PAGE_SIZE, 0,
    437 		    &sc->sc_txsoft[i].txs_dmamap)) != 0) {
    438 			aprint_error(": unable to create tx DMA map %d,"
    439 			    " error = %d\n", i, err);
    440 			goto fail_4;
    441 		}
    442 	}
    443 
    444 	callout_init(&sc->sc_tick_ch, 0);
    445 
    446 	/* get Ethernet address from ARCBIOS */
    447 	if ((macaddr = ARCBIOS->GetEnvironmentVariable("eaddr")) == NULL) {
    448 		aprint_error(": unable to get MAC address!\n");
    449 		goto fail_4;
    450 	}
    451 	/*
    452 	 * On some machines the DS2502 chip storing the serial number/
    453 	 * mac address is on the pci riser board - if this board is
    454 	 * missing, ARCBIOS will not know a good ethernet address (but
    455 	 * otherwise the machine will work fine).
    456 	 */
    457 	mac_is_fake = false;
    458 	if (strcmp(macaddr, "ff:ff:ff:ff:ff:ff") == 0) {
    459 		uint32_t ui = 0;
    460 		const char * netaddr =
    461 			ARCBIOS->GetEnvironmentVariable("netaddr");
    462 
    463 		/*
    464 		 * Create a MAC address by abusing the "netaddr" env var
    465 		 */
    466 		sc->sc_enaddr[0] = 0xf2;
    467 		sc->sc_enaddr[1] = 0x0b;
    468 		sc->sc_enaddr[2] = 0xa4;
    469 		if (netaddr) {
    470 			mac_is_fake = true;
    471 			while (*netaddr) {
    472 				int v = 0;
    473 				while (*netaddr && *netaddr != '.') {
    474 					if (*netaddr >= '0' && *netaddr <= '9')
    475 						v = v*10 + (*netaddr - '0');
    476 					netaddr++;
    477 				}
    478 				ui <<= 8;
    479 				ui |= v;
    480 				if (*netaddr == '.')
    481 					netaddr++;
    482 			}
    483 		}
    484 		memcpy(sc->sc_enaddr+3, ((uint8_t *)&ui)+1, 3);
    485 	}
    486 	if (!mac_is_fake)
    487 		enaddr_aton(macaddr, sc->sc_enaddr);
    488 
    489 	/* set the Ethernet address */
    490 	address = 0;
    491 	for (i = 0; i < ETHER_ADDR_LEN; i++) {
    492 		address = address << 8;
    493 		address |= sc->sc_enaddr[i];
    494 	}
    495 	bus_space_write_8(sc->sc_st, sc->sc_sh, MEC_STATION, address);
    496 
    497 	/* reset device */
    498 	mec_reset(sc);
    499 
    500 	command = bus_space_read_8(sc->sc_st, sc->sc_sh, MEC_MAC_CONTROL);
    501 
    502 	aprint_normal(": MAC-110 Ethernet, rev %u\n",
    503 	    (u_int)((command & MEC_MAC_REVISION) >> MEC_MAC_REVISION_SHIFT));
    504 
    505 	if (mac_is_fake)
    506 		aprint_normal_dev(self,
    507 		    "could not get ethernet address from firmware"
    508 		    " - generated one from the \"netaddr\" environment"
    509 		    " variable\n");
    510 	aprint_normal_dev(self, "Ethernet address %s\n",
    511 	    ether_sprintf(sc->sc_enaddr));
    512 
    513 	/* Done, now attach everything */
    514 
    515 	sc->sc_mii.mii_ifp = ifp;
    516 	sc->sc_mii.mii_readreg = mec_mii_readreg;
    517 	sc->sc_mii.mii_writereg = mec_mii_writereg;
    518 	sc->sc_mii.mii_statchg = mec_statchg;
    519 
    520 	/* Set up PHY properties */
    521 	sc->sc_ethercom.ec_mii = &sc->sc_mii;
    522 	ifmedia_init(&sc->sc_mii.mii_media, 0, ether_mediachange,
    523 	    ether_mediastatus);
    524 	mii_attach(self, &sc->sc_mii, 0xffffffff, MII_PHY_ANY,
    525 	    MII_OFFSET_ANY, 0);
    526 
    527 	child = LIST_FIRST(&sc->sc_mii.mii_phys);
    528 	if (child == NULL) {
    529 		/* No PHY attached */
    530 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER | IFM_MANUAL,
    531 		    0, NULL);
    532 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER | IFM_MANUAL);
    533 	} else {
    534 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER | IFM_AUTO);
    535 		sc->sc_phyaddr = child->mii_phy;
    536 	}
    537 
    538 	strcpy(ifp->if_xname, device_xname(self));
    539 	ifp->if_softc = sc;
    540 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
    541 	ifp->if_ioctl = mec_ioctl;
    542 	ifp->if_start = mec_start;
    543 	ifp->if_watchdog = mec_watchdog;
    544 	ifp->if_init = mec_init;
    545 	ifp->if_stop = mec_stop;
    546 	ifp->if_mtu = ETHERMTU;
    547 	IFQ_SET_READY(&ifp->if_snd);
    548 
    549 	if_attach(ifp);
    550 	ether_ifattach(ifp, sc->sc_enaddr);
    551 
    552 	/* establish interrupt */
    553 	cpu_intr_establish(maa->maa_intr, maa->maa_intrmask, mec_intr, sc);
    554 
    555 #if NRND > 0
    556 	rnd_attach_source(&sc->sc_rnd_source, device_xname(self),
    557 	    RND_TYPE_NET, 0);
    558 #endif
    559 
    560 	/* set shutdown hook to reset interface on powerdown */
    561 	sc->sc_sdhook = shutdownhook_establish(mec_shutdown, sc);
    562 
    563 	return;
    564 
    565 	/*
    566 	 * Free any resources we've allocated during the failed attach
    567 	 * attempt.  Do this in reverse order and fall though.
    568 	 */
    569  fail_4:
    570 	for (i = 0; i < MEC_NTXDESC; i++) {
    571 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
    572 			bus_dmamap_destroy(sc->sc_dmat,
    573 			    sc->sc_txsoft[i].txs_dmamap);
    574 	}
    575 	bus_dmamap_unload(sc->sc_dmat, sc->sc_cddmamap);
    576  fail_3:
    577 	bus_dmamap_destroy(sc->sc_dmat, sc->sc_cddmamap);
    578  fail_2:
    579 	bus_dmamem_unmap(sc->sc_dmat, (void *)sc->sc_control_data,
    580 	    sizeof(struct mec_control_data));
    581  fail_1:
    582 	bus_dmamem_free(sc->sc_dmat, &seg, rseg);
    583  fail_0:
    584 	return;
    585 }
    586 
    587 static int
    588 mec_mii_readreg(device_t self, int phy, int reg)
    589 {
    590 	struct mec_softc *sc = device_private(self);
    591 	bus_space_tag_t st = sc->sc_st;
    592 	bus_space_handle_t sh = sc->sc_sh;
    593 	uint64_t val;
    594 	int i;
    595 
    596 	if (mec_mii_wait(sc) != 0)
    597 		return 0;
    598 
    599 	bus_space_write_8(st, sh, MEC_PHY_ADDRESS,
    600 	    (phy << MEC_PHY_ADDR_DEVSHIFT) | (reg & MEC_PHY_ADDR_REGISTER));
    601 	delay(25);
    602 	bus_space_write_8(st, sh, MEC_PHY_READ_INITIATE, 1);
    603 	delay(25);
    604 	mec_mii_wait(sc);
    605 
    606 	for (i = 0; i < 20; i++) {
    607 		delay(30);
    608 
    609 		val = bus_space_read_8(st, sh, MEC_PHY_DATA);
    610 
    611 		if ((val & MEC_PHY_DATA_BUSY) == 0)
    612 			return val & MEC_PHY_DATA_VALUE;
    613 	}
    614 	return 0;
    615 }
    616 
    617 static void
    618 mec_mii_writereg(device_t self, int phy, int reg, int val)
    619 {
    620 	struct mec_softc *sc = device_private(self);
    621 	bus_space_tag_t st = sc->sc_st;
    622 	bus_space_handle_t sh = sc->sc_sh;
    623 
    624 	if (mec_mii_wait(sc) != 0) {
    625 		printf("timed out writing %x: %x\n", reg, val);
    626 		return;
    627 	}
    628 
    629 	bus_space_write_8(st, sh, MEC_PHY_ADDRESS,
    630 	    (phy << MEC_PHY_ADDR_DEVSHIFT) | (reg & MEC_PHY_ADDR_REGISTER));
    631 
    632 	delay(60);
    633 
    634 	bus_space_write_8(st, sh, MEC_PHY_DATA, val & MEC_PHY_DATA_VALUE);
    635 
    636 	delay(60);
    637 
    638 	mec_mii_wait(sc);
    639 }
    640 
    641 static int
    642 mec_mii_wait(struct mec_softc *sc)
    643 {
    644 	uint32_t busy;
    645 	int i, s;
    646 
    647 	for (i = 0; i < 100; i++) {
    648 		delay(30);
    649 
    650 		s = splhigh();
    651 		busy = bus_space_read_8(sc->sc_st, sc->sc_sh, MEC_PHY_DATA);
    652 		splx(s);
    653 
    654 		if ((busy & MEC_PHY_DATA_BUSY) == 0)
    655 			return 0;
    656 #if 0
    657 		if (busy == 0xffff) /* XXX ? */
    658 			return 0;
    659 #endif
    660 	}
    661 
    662 	printf("%s: MII timed out\n", device_xname(sc->sc_dev));
    663 	return 1;
    664 }
    665 
    666 static void
    667 mec_statchg(device_t self)
    668 {
    669 	struct mec_softc *sc = device_private(self);
    670 	bus_space_tag_t st = sc->sc_st;
    671 	bus_space_handle_t sh = sc->sc_sh;
    672 	uint32_t control;
    673 
    674 	control = bus_space_read_8(st, sh, MEC_MAC_CONTROL);
    675 	control &= ~(MEC_MAC_IPGT | MEC_MAC_IPGR1 | MEC_MAC_IPGR2 |
    676 	    MEC_MAC_FULL_DUPLEX | MEC_MAC_SPEED_SELECT);
    677 
    678 	/* must also set IPG here for duplex stuff ... */
    679 	if ((sc->sc_mii.mii_media_active & IFM_FDX) != 0) {
    680 		control |= MEC_MAC_FULL_DUPLEX;
    681 	} else {
    682 		/* set IPG */
    683 		control |= MEC_MAC_IPG_DEFAULT;
    684 	}
    685 
    686 	bus_space_write_8(st, sh, MEC_MAC_CONTROL, control);
    687 }
    688 
    689 /*
    690  * XXX
    691  * maybe this function should be moved to common part
    692  * (sgimips/machdep.c or elsewhere) for all on-board network devices.
    693  */
    694 static void
    695 enaddr_aton(const char *str, uint8_t *eaddr)
    696 {
    697 	int i;
    698 	char c;
    699 
    700 	for (i = 0; i < ETHER_ADDR_LEN; i++) {
    701 		if (*str == ':')
    702 			str++;
    703 
    704 		c = *str++;
    705 		if (isdigit(c)) {
    706 			eaddr[i] = (c - '0');
    707 		} else if (isxdigit(c)) {
    708 			eaddr[i] = (toupper(c) + 10 - 'A');
    709 		}
    710 		c = *str++;
    711 		if (isdigit(c)) {
    712 			eaddr[i] = (eaddr[i] << 4) | (c - '0');
    713 		} else if (isxdigit(c)) {
    714 			eaddr[i] = (eaddr[i] << 4) | (toupper(c) + 10 - 'A');
    715 		}
    716 	}
    717 }
    718 
    719 static int
    720 mec_init(struct ifnet *ifp)
    721 {
    722 	struct mec_softc *sc = ifp->if_softc;
    723 	bus_space_tag_t st = sc->sc_st;
    724 	bus_space_handle_t sh = sc->sc_sh;
    725 	struct mec_rxdesc *rxd;
    726 	int i, rc;
    727 
    728 	/* cancel any pending I/O */
    729 	mec_stop(ifp, 0);
    730 
    731 	/* reset device */
    732 	mec_reset(sc);
    733 
    734 	/* setup filter for multicast or promisc mode */
    735 	mec_setfilter(sc);
    736 
    737 	/* set the TX ring pointer to the base address */
    738 	bus_space_write_8(st, sh, MEC_TX_RING_BASE, MEC_CDTXADDR(sc, 0));
    739 
    740 	sc->sc_txpending = 0;
    741 	sc->sc_txdirty = 0;
    742 	sc->sc_txlast = MEC_NTXDESC - 1;
    743 
    744 	/* put RX buffers into FIFO */
    745 	for (i = 0; i < MEC_NRXDESC; i++) {
    746 		rxd = &sc->sc_rxdesc[i];
    747 		rxd->rxd_stat = 0;
    748 		MEC_RXSTATSYNC(sc, i, BUS_DMASYNC_PREREAD);
    749 		MEC_RXBUFSYNC(sc, i, ETHER_MAX_LEN, BUS_DMASYNC_PREREAD);
    750 		bus_space_write_8(st, sh, MEC_MCL_RX_FIFO, MEC_CDRXADDR(sc, i));
    751 	}
    752 	sc->sc_rxptr = 0;
    753 
    754 #if 0	/* XXX no info */
    755 	bus_space_write_8(st, sh, MEC_TIMER, 0);
    756 #endif
    757 
    758 	/*
    759 	 * MEC_DMA_TX_INT_ENABLE will be set later otherwise it causes
    760 	 * spurious interrupts when TX buffers are empty
    761 	 */
    762 	bus_space_write_8(st, sh, MEC_DMA_CONTROL,
    763 	    (MEC_RXD_DMAOFFSET << MEC_DMA_RX_DMA_OFFSET_SHIFT) |
    764 	    (MEC_NRXDESC << MEC_DMA_RX_INT_THRESH_SHIFT) |
    765 	    MEC_DMA_TX_DMA_ENABLE | /* MEC_DMA_TX_INT_ENABLE | */
    766 	    MEC_DMA_RX_DMA_ENABLE | MEC_DMA_RX_INT_ENABLE);
    767 
    768 	callout_reset(&sc->sc_tick_ch, hz, mec_tick, sc);
    769 
    770 	if ((rc = ether_mediachange(ifp)) != 0)
    771 		return rc;
    772 
    773 	ifp->if_flags |= IFF_RUNNING;
    774 	ifp->if_flags &= ~IFF_OACTIVE;
    775 	mec_start(ifp);
    776 
    777 	return 0;
    778 }
    779 
    780 static void
    781 mec_reset(struct mec_softc *sc)
    782 {
    783 	bus_space_tag_t st = sc->sc_st;
    784 	bus_space_handle_t sh = sc->sc_sh;
    785 	uint64_t control;
    786 
    787 	/* stop DMA first */
    788 	bus_space_write_8(st, sh, MEC_DMA_CONTROL, 0);
    789 
    790 	/* reset chip */
    791 	bus_space_write_8(st, sh, MEC_MAC_CONTROL, MEC_MAC_CORE_RESET);
    792 	delay(1000);
    793 	bus_space_write_8(st, sh, MEC_MAC_CONTROL, 0);
    794 	delay(1000);
    795 
    796 	/* Default to 100/half and let auto-negotiation work its magic */
    797 	control = MEC_MAC_SPEED_SELECT | MEC_MAC_FILTER_MATCHMULTI |
    798 	    MEC_MAC_IPG_DEFAULT;
    799 
    800 	bus_space_write_8(st, sh, MEC_MAC_CONTROL, control);
    801 	/* stop DMA again for sanity */
    802 	bus_space_write_8(st, sh, MEC_DMA_CONTROL, 0);
    803 
    804 	DPRINTF(MEC_DEBUG_RESET, ("mec: control now %llx\n",
    805 	    bus_space_read_8(st, sh, MEC_MAC_CONTROL)));
    806 }
    807 
    808 static void
    809 mec_start(struct ifnet *ifp)
    810 {
    811 	struct mec_softc *sc = ifp->if_softc;
    812 	struct mbuf *m0, *m;
    813 	struct mec_txdesc *txd;
    814 	struct mec_txsoft *txs;
    815 	bus_dmamap_t dmamap;
    816 	bus_space_tag_t st = sc->sc_st;
    817 	bus_space_handle_t sh = sc->sc_sh;
    818 	uint64_t txdaddr;
    819 	int error, firsttx, nexttx, opending;
    820 	int len, bufoff, buflen, unaligned, txdlen;
    821 
    822 	if ((ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)
    823 		return;
    824 
    825 	/*
    826 	 * Remember the previous txpending and the first transmit descriptor.
    827 	 */
    828 	opending = sc->sc_txpending;
    829 	firsttx = MEC_NEXTTX(sc->sc_txlast);
    830 
    831 	DPRINTF(MEC_DEBUG_START,
    832 	    ("mec_start: opending = %d, firsttx = %d\n", opending, firsttx));
    833 
    834 	while (sc->sc_txpending < MEC_NTXDESC - 1) {
    835 		/* Grab a packet off the queue. */
    836 		IFQ_POLL(&ifp->if_snd, m0);
    837 		if (m0 == NULL)
    838 			break;
    839 		m = NULL;
    840 
    841 		/*
    842 		 * Get the next available transmit descriptor.
    843 		 */
    844 		nexttx = MEC_NEXTTX(sc->sc_txlast);
    845 		txd = &sc->sc_txdesc[nexttx];
    846 		txs = &sc->sc_txsoft[nexttx];
    847 
    848 		buflen = 0;
    849 		bufoff = 0;
    850 		txdaddr = 0; /* XXX gcc */
    851 		txdlen = 0; /* XXX gcc */
    852 
    853 		len = m0->m_pkthdr.len;
    854 
    855 		DPRINTF(MEC_DEBUG_START,
    856 		    ("mec_start: len = %d, nexttx = %d\n", len, nexttx));
    857 
    858 		if (len < ETHER_PAD_LEN) {
    859 			/*
    860 			 * I don't know if MEC chip does auto padding,
    861 			 * so if the packet is small enough,
    862 			 * just copy it to the buffer in txdesc.
    863 			 * Maybe this is the simple way.
    864 			 */
    865 			DPRINTF(MEC_DEBUG_START, ("mec_start: short packet\n"));
    866 
    867 			IFQ_DEQUEUE(&ifp->if_snd, m0);
    868 			bufoff = MEC_TXD_BUFSTART(ETHER_PAD_LEN);
    869 			m_copydata(m0, 0, m0->m_pkthdr.len,
    870 			    txd->txd_buf + bufoff);
    871 			memset(txd->txd_buf + bufoff + len, 0,
    872 			    ETHER_PAD_LEN - len);
    873 			len = buflen = ETHER_PAD_LEN;
    874 
    875 			txs->txs_flags = MEC_TXS_TXDBUF | buflen;
    876 		} else {
    877 			/*
    878 			 * If the packet won't fit the buffer in txdesc,
    879 			 * we have to use concatenate pointer to handle it.
    880 			 * While MEC can handle up to three segments to
    881 			 * concatenate, MEC requires that both the second and
    882 			 * third segments have to be 8 byte aligned.
    883 			 * Since it's unlikely for mbuf clusters, we use
    884 			 * only the first concatenate pointer. If the packet
    885 			 * doesn't fit in one DMA segment, allocate new mbuf
    886 			 * and copy the packet to it.
    887 			 *
    888 			 * Besides, if the start address of the first segments
    889 			 * is not 8 byte aligned, such part have to be copied
    890 			 * to the txdesc buffer. (XXX see below comments)
    891 	                 */
    892 			DPRINTF(MEC_DEBUG_START, ("mec_start: long packet\n"));
    893 
    894 			dmamap = txs->txs_dmamap;
    895 			if (bus_dmamap_load_mbuf(sc->sc_dmat, dmamap, m0,
    896 			    BUS_DMA_WRITE | BUS_DMA_NOWAIT) != 0) {
    897 				DPRINTF(MEC_DEBUG_START,
    898 				    ("mec_start: re-allocating mbuf\n"));
    899 				MGETHDR(m, M_DONTWAIT, MT_DATA);
    900 				if (m == NULL) {
    901 					printf("%s: unable to allocate "
    902 					    "TX mbuf\n",
    903 					    device_xname(sc->sc_dev));
    904 					break;
    905 				}
    906 				if (len > (MHLEN - MEC_ETHER_ALIGN)) {
    907 					MCLGET(m, M_DONTWAIT);
    908 					if ((m->m_flags & M_EXT) == 0) {
    909 						printf("%s: unable to allocate "
    910 						    "TX cluster\n",
    911 						    device_xname(sc->sc_dev));
    912 						m_freem(m);
    913 						break;
    914 					}
    915 				}
    916 				/*
    917 				 * Each packet has the Ethernet header, so
    918 				 * in many case the header isn't 4-byte aligned
    919 				 * and data after the header is 4-byte aligned.
    920 				 * Thus adding 2-byte offset before copying to
    921 				 * new mbuf avoids unaligned copy and this may
    922 				 * improve some performance.
    923 				 * As noted above, unaligned part has to be
    924 				 * copied to txdesc buffer so this may cause
    925 				 * extra copy ops, but for now MEC always
    926 				 * requires some data in txdesc buffer,
    927 				 * so we always have to copy some data anyway.
    928 				 */
    929 				m->m_data += MEC_ETHER_ALIGN;
    930 				m_copydata(m0, 0, len, mtod(m, void *));
    931 				m->m_pkthdr.len = m->m_len = len;
    932 				error = bus_dmamap_load_mbuf(sc->sc_dmat,
    933 				    dmamap, m, BUS_DMA_WRITE | BUS_DMA_NOWAIT);
    934 				if (error) {
    935 					printf("%s: unable to load TX buffer, "
    936 					    "error = %d\n",
    937 					    device_xname(sc->sc_dev), error);
    938 					break;
    939 				}
    940 			}
    941 			IFQ_DEQUEUE(&ifp->if_snd, m0);
    942 			if (m != NULL) {
    943 				m_freem(m0);
    944 				m0 = m;
    945 			}
    946 
    947 			/* handle unaligned part */
    948 			txdaddr = MEC_TXD_ROUNDUP(dmamap->dm_segs[0].ds_addr);
    949 			txs->txs_flags = MEC_TXS_TXDPTR1;
    950 			unaligned =
    951 			    dmamap->dm_segs[0].ds_addr & (MEC_TXD_ALIGN - 1);
    952 			DPRINTF(MEC_DEBUG_START,
    953 			    ("mec_start: ds_addr = 0x%08x, unaligned = %d\n",
    954 			    (u_int)dmamap->dm_segs[0].ds_addr, unaligned));
    955 			if (unaligned != 0) {
    956 				buflen = MEC_TXD_ALIGN - unaligned;
    957 				bufoff = MEC_TXD_BUFSTART(buflen);
    958 				DPRINTF(MEC_DEBUG_START,
    959 				    ("mec_start: unaligned, "
    960 				    "buflen = %d, bufoff = %d\n",
    961 				    buflen, bufoff));
    962 				memcpy(txd->txd_buf + bufoff,
    963 				    mtod(m0, void *), buflen);
    964 				txs->txs_flags |= MEC_TXS_TXDBUF | buflen;
    965 			}
    966 #if 1
    967 			else {
    968 				/*
    969 				 * XXX needs hardware info XXX
    970 				 * It seems MEC always requires some data
    971 				 * in txd_buf[] even if buffer is
    972 				 * 8-byte aligned otherwise DMA abort error
    973 				 * occurs later...
    974 				 */
    975 				buflen = MEC_TXD_ALIGN;
    976 				bufoff = MEC_TXD_BUFSTART(buflen);
    977 				memcpy(txd->txd_buf + bufoff,
    978 				    mtod(m0, void *), buflen);
    979 				DPRINTF(MEC_DEBUG_START,
    980 				    ("mec_start: aligned, "
    981 				    "buflen = %d, bufoff = %d\n",
    982 				    buflen, bufoff));
    983 				txs->txs_flags |= MEC_TXS_TXDBUF | buflen;
    984 				txdaddr += MEC_TXD_ALIGN;
    985 			}
    986 #endif
    987 			txdlen  = len - buflen;
    988 			DPRINTF(MEC_DEBUG_START,
    989 			    ("mec_start: txdaddr = 0x%08llx, txdlen = %d\n",
    990 			    txdaddr, txdlen));
    991 
    992 			/*
    993 			 * sync the DMA map for TX mbuf
    994 			 *
    995 			 * XXX unaligned part doesn't have to be sync'ed,
    996 			 *     but it's harmless...
    997 			 */
    998 			bus_dmamap_sync(sc->sc_dmat, dmamap, 0,
    999 			    dmamap->dm_mapsize,	BUS_DMASYNC_PREWRITE);
   1000 		}
   1001 
   1002 #if NBPFILTER > 0
   1003 		/*
   1004 		 * Pass packet to bpf if there is a listener.
   1005 		 */
   1006 		if (ifp->if_bpf)
   1007 			bpf_mtap(ifp->if_bpf, m0);
   1008 #endif
   1009 
   1010 		/*
   1011 		 * setup the transmit descriptor.
   1012 		 */
   1013 		txd->txd_cmd = (len - 1);
   1014 
   1015 		/*
   1016 		 * Set MEC_TXCMD_TXINT every MEC_NTXDESC_INTR packets
   1017 		 * if more than half txdescs have been queued
   1018 		 * because TX_EMPTY interrupts will rarely happen
   1019 		 * if TX queue is so stacked.
   1020 		 */
   1021 		if (sc->sc_txpending > (MEC_NTXDESC / 2) &&
   1022 		    (nexttx & (MEC_NTXDESC_INTR - 1)) == 0)
   1023 			txd->txd_cmd |= MEC_TXCMD_TXINT;
   1024 
   1025 		if (txs->txs_flags & MEC_TXS_TXDBUF)
   1026 			txd->txd_cmd |= TXCMD_BUFSTART(MEC_TXDESCSIZE - buflen);
   1027 		if (txs->txs_flags & MEC_TXS_TXDPTR1) {
   1028 			txd->txd_cmd |= MEC_TXCMD_PTR1;
   1029 			txd->txd_ptr[0] = TXPTR_LEN(txdlen - 1) | txdaddr;
   1030 			/*
   1031 			 * Store a pointer to the packet so we can
   1032 			 * free it later.
   1033 			 */
   1034 			txs->txs_mbuf = m0;
   1035 		} else {
   1036 			txd->txd_ptr[0] = 0;
   1037 			/*
   1038 			 * In this case all data are copied to buffer in txdesc,
   1039 			 * we can free TX mbuf here.
   1040 			 */
   1041 			m_freem(m0);
   1042 		}
   1043 
   1044 		DPRINTF(MEC_DEBUG_START,
   1045 		    ("mec_start: txd_cmd = 0x%016llx, txd_ptr = 0x%016llx\n",
   1046 		    txd->txd_cmd, txd->txd_ptr[0]));
   1047 		DPRINTF(MEC_DEBUG_START,
   1048 		    ("mec_start: len = %d (0x%04x), buflen = %d (0x%02x)\n",
   1049 		    len, len, buflen, buflen));
   1050 
   1051 		/* sync TX descriptor */
   1052 		MEC_TXDESCSYNC(sc, nexttx,
   1053 		    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
   1054 
   1055 		/* start TX */
   1056 		bus_space_write_8(st, sh, MEC_TX_RING_PTR, MEC_NEXTTX(nexttx));
   1057 
   1058 		/* advance the TX pointer. */
   1059 		sc->sc_txpending++;
   1060 		sc->sc_txlast = nexttx;
   1061 	}
   1062 
   1063 	if (sc->sc_txpending == MEC_NTXDESC - 1) {
   1064 		/* No more slots; notify upper layer. */
   1065 		ifp->if_flags |= IFF_OACTIVE;
   1066 	}
   1067 
   1068 	if (sc->sc_txpending != opending) {
   1069 		/*
   1070 		 * If the transmitter was idle,
   1071 		 * reset the txdirty pointer and re-enable TX interrupt.
   1072 		 */
   1073 		if (opending == 0) {
   1074 			sc->sc_txdirty = firsttx;
   1075 			bus_space_write_8(st, sh, MEC_TX_ALIAS,
   1076 			    MEC_TX_ALIAS_INT_ENABLE);
   1077 		}
   1078 
   1079 		/* Set a watchdog timer in case the chip flakes out. */
   1080 		ifp->if_timer = 5;
   1081 	}
   1082 }
   1083 
   1084 static void
   1085 mec_stop(struct ifnet *ifp, int disable)
   1086 {
   1087 	struct mec_softc *sc = ifp->if_softc;
   1088 	struct mec_txsoft *txs;
   1089 	int i;
   1090 
   1091 	DPRINTF(MEC_DEBUG_STOP, ("mec_stop\n"));
   1092 
   1093 	ifp->if_timer = 0;
   1094 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
   1095 
   1096 	callout_stop(&sc->sc_tick_ch);
   1097 	mii_down(&sc->sc_mii);
   1098 
   1099 	/* release any TX buffers */
   1100 	for (i = 0; i < MEC_NTXDESC; i++) {
   1101 		txs = &sc->sc_txsoft[i];
   1102 		if ((txs->txs_flags & MEC_TXS_TXDPTR1) != 0) {
   1103 			bus_dmamap_unload(sc->sc_dmat, txs->txs_dmamap);
   1104 			m_freem(txs->txs_mbuf);
   1105 			txs->txs_mbuf = NULL;
   1106 		}
   1107 	}
   1108 }
   1109 
   1110 static int
   1111 mec_ioctl(struct ifnet *ifp, u_long cmd, void *data)
   1112 {
   1113 	int s, error;
   1114 
   1115 	s = splnet();
   1116 
   1117 	error = ether_ioctl(ifp, cmd, data);
   1118 	if (error == ENETRESET) {
   1119 		/*
   1120 		 * Multicast list has changed; set the hardware filter
   1121 		 * accordingly.
   1122 		 */
   1123 		if (ifp->if_flags & IFF_RUNNING)
   1124 			error = mec_init(ifp);
   1125 		else
   1126 			error = 0;
   1127 	}
   1128 
   1129 	/* Try to get more packets going. */
   1130 	mec_start(ifp);
   1131 
   1132 	splx(s);
   1133 	return error;
   1134 }
   1135 
   1136 static void
   1137 mec_watchdog(struct ifnet *ifp)
   1138 {
   1139 	struct mec_softc *sc = ifp->if_softc;
   1140 
   1141 	printf("%s: device timeout\n", device_xname(sc->sc_dev));
   1142 	ifp->if_oerrors++;
   1143 
   1144 	mec_init(ifp);
   1145 }
   1146 
   1147 static void
   1148 mec_tick(void *arg)
   1149 {
   1150 	struct mec_softc *sc = arg;
   1151 	int s;
   1152 
   1153 	s = splnet();
   1154 	mii_tick(&sc->sc_mii);
   1155 	splx(s);
   1156 
   1157 	callout_reset(&sc->sc_tick_ch, hz, mec_tick, sc);
   1158 }
   1159 
   1160 static void
   1161 mec_setfilter(struct mec_softc *sc)
   1162 {
   1163 	struct ethercom *ec = &sc->sc_ethercom;
   1164 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
   1165 	struct ether_multi *enm;
   1166 	struct ether_multistep step;
   1167 	bus_space_tag_t st = sc->sc_st;
   1168 	bus_space_handle_t sh = sc->sc_sh;
   1169 	uint64_t mchash;
   1170 	uint32_t control, hash;
   1171 	int mcnt;
   1172 
   1173 	control = bus_space_read_8(st, sh, MEC_MAC_CONTROL);
   1174 	control &= ~MEC_MAC_FILTER_MASK;
   1175 
   1176 	if (ifp->if_flags & IFF_PROMISC) {
   1177 		control |= MEC_MAC_FILTER_PROMISC;
   1178 		bus_space_write_8(st, sh, MEC_MULTICAST, 0xffffffffffffffffULL);
   1179 		bus_space_write_8(st, sh, MEC_MAC_CONTROL, control);
   1180 		return;
   1181 	}
   1182 
   1183 	mcnt = 0;
   1184 	mchash = 0;
   1185 	ETHER_FIRST_MULTI(step, ec, enm);
   1186 	while (enm != NULL) {
   1187 		if (memcmp(enm->enm_addrlo, enm->enm_addrhi, ETHER_ADDR_LEN)) {
   1188 			/* set allmulti for a range of multicast addresses */
   1189 			control |= MEC_MAC_FILTER_ALLMULTI;
   1190 			bus_space_write_8(st, sh, MEC_MULTICAST,
   1191 			    0xffffffffffffffffULL);
   1192 			bus_space_write_8(st, sh, MEC_MAC_CONTROL, control);
   1193 			return;
   1194 		}
   1195 
   1196 #define mec_calchash(addr)	(ether_crc32_be((addr), ETHER_ADDR_LEN) >> 26)
   1197 
   1198 		hash = mec_calchash(enm->enm_addrlo);
   1199 		mchash |= 1 << hash;
   1200 		mcnt++;
   1201 		ETHER_NEXT_MULTI(step, enm);
   1202 	}
   1203 
   1204 	ifp->if_flags &= ~IFF_ALLMULTI;
   1205 
   1206 	if (mcnt > 0)
   1207 		control |= MEC_MAC_FILTER_MATCHMULTI;
   1208 
   1209 	bus_space_write_8(st, sh, MEC_MULTICAST, mchash);
   1210 	bus_space_write_8(st, sh, MEC_MAC_CONTROL, control);
   1211 }
   1212 
   1213 static int
   1214 mec_intr(void *arg)
   1215 {
   1216 	struct mec_softc *sc = arg;
   1217 	bus_space_tag_t st = sc->sc_st;
   1218 	bus_space_handle_t sh = sc->sc_sh;
   1219 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
   1220 	uint32_t statreg, statack, txptr;
   1221 	int handled, sent;
   1222 
   1223 	DPRINTF(MEC_DEBUG_INTR, ("mec_intr: called\n"));
   1224 
   1225 	handled = sent = 0;
   1226 
   1227 	for (;;) {
   1228 		statreg = bus_space_read_8(st, sh, MEC_INT_STATUS);
   1229 
   1230 		DPRINTF(MEC_DEBUG_INTR,
   1231 		    ("mec_intr: INT_STAT = 0x%08x\n", statreg));
   1232 
   1233 		statack = statreg & MEC_INT_STATUS_MASK;
   1234 		if (statack == 0)
   1235 			break;
   1236 		bus_space_write_8(st, sh, MEC_INT_STATUS, statack);
   1237 
   1238 		handled = 1;
   1239 
   1240 		if (statack &
   1241 		    (MEC_INT_RX_THRESHOLD |
   1242 		     MEC_INT_RX_FIFO_UNDERFLOW)) {
   1243 			mec_rxintr(sc);
   1244 		}
   1245 
   1246 		if (statack &
   1247 		    (MEC_INT_TX_EMPTY |
   1248 		     MEC_INT_TX_PACKET_SENT |
   1249 		     MEC_INT_TX_ABORT)) {
   1250 			txptr = (statreg & MEC_INT_TX_RING_BUFFER_ALIAS)
   1251 			    >> MEC_INT_TX_RING_BUFFER_SHIFT;
   1252 			mec_txintr(sc, txptr);
   1253 			sent = 1;
   1254 			if ((statack & MEC_INT_TX_EMPTY) != 0) {
   1255 				/*
   1256 				 * disable TX interrupt to stop
   1257 				 * TX empty interrupt
   1258 				 */
   1259 				bus_space_write_8(st, sh, MEC_TX_ALIAS, 0);
   1260 				DPRINTF(MEC_DEBUG_INTR,
   1261 				    ("mec_intr: disable TX_INT\n"));
   1262 			}
   1263 		}
   1264 
   1265 		if (statack &
   1266 		    (MEC_INT_TX_LINK_FAIL |
   1267 		     MEC_INT_TX_MEM_ERROR |
   1268 		     MEC_INT_TX_ABORT |
   1269 		     MEC_INT_RX_FIFO_UNDERFLOW |
   1270 		     MEC_INT_RX_DMA_UNDERFLOW)) {
   1271 			printf("%s: mec_intr: interrupt status = 0x%08x\n",
   1272 			    device_xname(sc->sc_dev), statreg);
   1273 			mec_init(ifp);
   1274 			break;
   1275 		}
   1276 	}
   1277 
   1278 	if (sent && !IFQ_IS_EMPTY(&ifp->if_snd)) {
   1279 		/* try to get more packets going */
   1280 		mec_start(ifp);
   1281 	}
   1282 
   1283 #if NRND > 0
   1284 	if (handled)
   1285 		rnd_add_uint32(&sc->sc_rnd_source, statreg);
   1286 #endif
   1287 
   1288 	return handled;
   1289 }
   1290 
   1291 static void
   1292 mec_rxintr(struct mec_softc *sc)
   1293 {
   1294 	bus_space_tag_t st = sc->sc_st;
   1295 	bus_space_handle_t sh = sc->sc_sh;
   1296 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
   1297 	struct mbuf *m;
   1298 	struct mec_rxdesc *rxd;
   1299 	uint64_t rxstat;
   1300 	u_int len;
   1301 	int i;
   1302 
   1303 	DPRINTF(MEC_DEBUG_RXINTR, ("mec_rxintr: called\n"));
   1304 
   1305 	for (i = sc->sc_rxptr;; i = MEC_NEXTRX(i)) {
   1306 		rxd = &sc->sc_rxdesc[i];
   1307 
   1308 		MEC_RXSTATSYNC(sc, i, BUS_DMASYNC_POSTREAD);
   1309 		rxstat = rxd->rxd_stat;
   1310 
   1311 		DPRINTF(MEC_DEBUG_RXINTR,
   1312 		    ("mec_rxintr: rxstat = 0x%016llx, rxptr = %d\n",
   1313 		    rxstat, i));
   1314 		DPRINTF(MEC_DEBUG_RXINTR, ("mec_rxintr: rxfifo = 0x%08x\n",
   1315 		    (u_int)bus_space_read_8(st, sh, MEC_RX_FIFO)));
   1316 
   1317 		if ((rxstat & MEC_RXSTAT_RECEIVED) == 0) {
   1318 			MEC_RXSTATSYNC(sc, i, BUS_DMASYNC_PREREAD);
   1319 			break;
   1320 		}
   1321 
   1322 		len = rxstat & MEC_RXSTAT_LEN;
   1323 
   1324 		if (len < ETHER_MIN_LEN ||
   1325 		    len > (MCLBYTES - MEC_ETHER_ALIGN)) {
   1326 			/* invalid length packet; drop it. */
   1327 			DPRINTF(MEC_DEBUG_RXINTR,
   1328 			    ("mec_rxintr: wrong packet\n"));
   1329  dropit:
   1330 			ifp->if_ierrors++;
   1331 			rxd->rxd_stat = 0;
   1332 			MEC_RXSTATSYNC(sc, i, BUS_DMASYNC_PREREAD);
   1333 			bus_space_write_8(st, sh, MEC_MCL_RX_FIFO,
   1334 			    MEC_CDRXADDR(sc, i));
   1335 			continue;
   1336 		}
   1337 
   1338 		if (rxstat &
   1339 		    (MEC_RXSTAT_BADPACKET |
   1340 		     MEC_RXSTAT_LONGEVENT |
   1341 		     MEC_RXSTAT_INVALID   |
   1342 		     MEC_RXSTAT_CRCERROR  |
   1343 		     MEC_RXSTAT_VIOLATION)) {
   1344 			printf("%s: mec_rxintr: status = 0x%016llx\n",
   1345 			    device_xname(sc->sc_dev), rxstat);
   1346 			goto dropit;
   1347 		}
   1348 
   1349 		/*
   1350 		 * The MEC includes the CRC with every packet.  Trim
   1351 		 * it off here.
   1352 		 */
   1353 		len -= ETHER_CRC_LEN;
   1354 
   1355 		/*
   1356 		 * now allocate an mbuf (and possibly a cluster) to hold
   1357 		 * the received packet.
   1358 		 */
   1359 		MGETHDR(m, M_DONTWAIT, MT_DATA);
   1360 		if (m == NULL) {
   1361 			printf("%s: unable to allocate RX mbuf\n",
   1362 			    device_xname(sc->sc_dev));
   1363 			goto dropit;
   1364 		}
   1365 		if (len > (MHLEN - MEC_ETHER_ALIGN)) {
   1366 			MCLGET(m, M_DONTWAIT);
   1367 			if ((m->m_flags & M_EXT) == 0) {
   1368 				printf("%s: unable to allocate RX cluster\n",
   1369 				    device_xname(sc->sc_dev));
   1370 				m_freem(m);
   1371 				m = NULL;
   1372 				goto dropit;
   1373 			}
   1374 		}
   1375 
   1376 		/*
   1377 		 * Note MEC chip seems to insert 2 byte padding at the top of
   1378 		 * RX buffer, but we copy whole buffer to avoid unaligned copy.
   1379 		 */
   1380 		MEC_RXBUFSYNC(sc, i, len, BUS_DMASYNC_POSTREAD);
   1381 		memcpy(mtod(m, void *), rxd->rxd_buf, MEC_ETHER_ALIGN + len);
   1382 		MEC_RXBUFSYNC(sc, i, ETHER_MAX_LEN, BUS_DMASYNC_PREREAD);
   1383 		m->m_data += MEC_ETHER_ALIGN;
   1384 
   1385 		/* put RX buffer into FIFO again */
   1386 		rxd->rxd_stat = 0;
   1387 		MEC_RXSTATSYNC(sc, i, BUS_DMASYNC_PREREAD);
   1388 		bus_space_write_8(st, sh, MEC_MCL_RX_FIFO, MEC_CDRXADDR(sc, i));
   1389 
   1390 		m->m_pkthdr.rcvif = ifp;
   1391 		m->m_pkthdr.len = m->m_len = len;
   1392 
   1393 		ifp->if_ipackets++;
   1394 
   1395 #if NBPFILTER > 0
   1396 		/*
   1397 		 * Pass this up to any BPF listeners, but only
   1398 		 * pass it up the stack if it's for us.
   1399 		 */
   1400 		if (ifp->if_bpf)
   1401 			bpf_mtap(ifp->if_bpf, m);
   1402 #endif
   1403 
   1404 		/* Pass it on. */
   1405 		(*ifp->if_input)(ifp, m);
   1406 	}
   1407 
   1408 	/* update RX pointer */
   1409 	sc->sc_rxptr = i;
   1410 }
   1411 
   1412 static void
   1413 mec_txintr(struct mec_softc *sc, uint32_t txptr)
   1414 {
   1415 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
   1416 	struct mec_txdesc *txd;
   1417 	struct mec_txsoft *txs;
   1418 	bus_dmamap_t dmamap;
   1419 	uint64_t txstat;
   1420 	int i;
   1421 	u_int col;
   1422 
   1423 	DPRINTF(MEC_DEBUG_TXINTR, ("mec_txintr: called\n"));
   1424 
   1425 	for (i = sc->sc_txdirty; i != txptr && sc->sc_txpending != 0;
   1426 	    i = MEC_NEXTTX(i), sc->sc_txpending--) {
   1427 		txd = &sc->sc_txdesc[i];
   1428 
   1429 		MEC_TXDESCSYNC(sc, i,
   1430 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
   1431 
   1432 		txstat = txd->txd_stat;
   1433 		DPRINTF(MEC_DEBUG_TXINTR,
   1434 		    ("mec_txintr: dirty = %d, txstat = 0x%016llx\n",
   1435 		    i, txstat));
   1436 		if ((txstat & MEC_TXSTAT_SENT) == 0) {
   1437 			MEC_TXCMDSYNC(sc, i, BUS_DMASYNC_PREREAD);
   1438 			break;
   1439 		}
   1440 
   1441 		txs = &sc->sc_txsoft[i];
   1442 		if ((txs->txs_flags & MEC_TXS_TXDPTR1) != 0) {
   1443 			dmamap = txs->txs_dmamap;
   1444 			bus_dmamap_sync(sc->sc_dmat, dmamap, 0,
   1445 			    dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
   1446 			bus_dmamap_unload(sc->sc_dmat, dmamap);
   1447 			m_freem(txs->txs_mbuf);
   1448 			txs->txs_mbuf = NULL;
   1449 		}
   1450 
   1451 		col = (txstat & MEC_TXSTAT_COLCNT) >> MEC_TXSTAT_COLCNT_SHIFT;
   1452 		ifp->if_collisions += col;
   1453 
   1454 		if ((txstat & MEC_TXSTAT_SUCCESS) == 0) {
   1455 			printf("%s: TX error: txstat = 0x%016llx\n",
   1456 			    device_xname(sc->sc_dev), txstat);
   1457 			ifp->if_oerrors++;
   1458 		} else
   1459 			ifp->if_opackets++;
   1460 	}
   1461 
   1462 	/* update the dirty TX buffer pointer */
   1463 	sc->sc_txdirty = i;
   1464 	DPRINTF(MEC_DEBUG_INTR,
   1465 	    ("mec_txintr: sc_txdirty = %2d, sc_txpending = %2d\n",
   1466 	    sc->sc_txdirty, sc->sc_txpending));
   1467 
   1468 	/* cancel the watchdog timer if there are no pending TX packets */
   1469 	if (sc->sc_txpending == 0)
   1470 		ifp->if_timer = 0;
   1471 	if (sc->sc_txpending < MEC_NTXDESC - MEC_NTXDESC_RSVD)
   1472 		ifp->if_flags &= ~IFF_OACTIVE;
   1473 }
   1474 
   1475 static void
   1476 mec_shutdown(void *arg)
   1477 {
   1478 	struct mec_softc *sc = arg;
   1479 
   1480 	mec_stop(&sc->sc_ethercom.ec_if, 1);
   1481 	/* make sure to stop DMA etc. */
   1482 	mec_reset(sc);
   1483 }
   1484