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if_emac.c revision 1.45
      1 /*	$NetBSD: if_emac.c,v 1.45 2016/06/10 13:27:12 ozaki-r Exp $	*/
      2 
      3 /*
      4  * Copyright 2001, 2002 Wasabi Systems, Inc.
      5  * All rights reserved.
      6  *
      7  * Written by Simon Burge and Jason Thorpe for Wasabi Systems, Inc.
      8  *
      9  * Redistribution and use in source and binary forms, with or without
     10  * modification, are permitted provided that the following conditions
     11  * are met:
     12  * 1. Redistributions of source code must retain the above copyright
     13  *    notice, this list of conditions and the following disclaimer.
     14  * 2. Redistributions in binary form must reproduce the above copyright
     15  *    notice, this list of conditions and the following disclaimer in the
     16  *    documentation and/or other materials provided with the distribution.
     17  * 3. All advertising materials mentioning features or use of this software
     18  *    must display the following acknowledgement:
     19  *      This product includes software developed for the NetBSD Project by
     20  *      Wasabi Systems, Inc.
     21  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
     22  *    or promote products derived from this software without specific prior
     23  *    written permission.
     24  *
     25  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
     26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
     29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     35  * POSSIBILITY OF SUCH DAMAGE.
     36  */
     37 
     38 /*
     39  * emac(4) supports following ibm4xx's EMACs.
     40  *   XXXX: ZMII and 'TCP Accelaration Hardware' not support yet...
     41  *
     42  *            tested
     43  *            ------
     44  * 405EP	-  10/100 x2
     45  * 405EX/EXr	o  10/100/1000 x2 (EXr x1), STA v2, 256bit hash-Table, RGMII
     46  * 405GP/GPr	o  10/100
     47  * 440EP	-  10/100 x2, ZMII
     48  * 440GP	-  10/100 x2, ZMII
     49  * 440GX	-  10/100/1000 x4, ZMII/RGMII(ch 2, 3), TAH(ch 2, 3)
     50  * 440SP	-  10/100/1000
     51  * 440SPe	-  10/100/1000, STA v2
     52  */
     53 
     54 #include <sys/cdefs.h>
     55 __KERNEL_RCSID(0, "$NetBSD: if_emac.c,v 1.45 2016/06/10 13:27:12 ozaki-r Exp $");
     56 
     57 #include "opt_emac.h"
     58 
     59 #include <sys/param.h>
     60 #include <sys/systm.h>
     61 #include <sys/mbuf.h>
     62 #include <sys/kernel.h>
     63 #include <sys/socket.h>
     64 #include <sys/ioctl.h>
     65 #include <sys/cpu.h>
     66 #include <sys/device.h>
     67 
     68 #include <uvm/uvm_extern.h>		/* for PAGE_SIZE */
     69 
     70 #include <net/if.h>
     71 #include <net/if_dl.h>
     72 #include <net/if_media.h>
     73 #include <net/if_ether.h>
     74 
     75 #include <net/bpf.h>
     76 
     77 #include <powerpc/ibm4xx/cpu.h>
     78 #include <powerpc/ibm4xx/dcr4xx.h>
     79 #include <powerpc/ibm4xx/mal405gp.h>
     80 #include <powerpc/ibm4xx/dev/emacreg.h>
     81 #include <powerpc/ibm4xx/dev/if_emacreg.h>
     82 #include <powerpc/ibm4xx/dev/if_emacvar.h>
     83 #include <powerpc/ibm4xx/dev/malvar.h>
     84 #include <powerpc/ibm4xx/dev/opbreg.h>
     85 #include <powerpc/ibm4xx/dev/opbvar.h>
     86 #include <powerpc/ibm4xx/dev/plbvar.h>
     87 #if defined(EMAC_ZMII_PHY) || defined(EMAC_RGMII_PHY)
     88 #include <powerpc/ibm4xx/dev/rmiivar.h>
     89 #endif
     90 
     91 #include <dev/mii/miivar.h>
     92 
     93 #include "locators.h"
     94 
     95 
     96 /*
     97  * Transmit descriptor list size.  There are two Tx channels, each with
     98  * up to 256 hardware descriptors available.  We currently use one Tx
     99  * channel.  We tell the upper layers that they can queue a lot of
    100  * packets, and we go ahead and manage up to 64 of them at a time.  We
    101  * allow up to 16 DMA segments per packet.
    102  */
    103 #define	EMAC_NTXSEGS		16
    104 #define	EMAC_TXQUEUELEN		64
    105 #define	EMAC_TXQUEUELEN_MASK	(EMAC_TXQUEUELEN - 1)
    106 #define	EMAC_TXQUEUE_GC		(EMAC_TXQUEUELEN / 4)
    107 #define	EMAC_NTXDESC		256
    108 #define	EMAC_NTXDESC_MASK	(EMAC_NTXDESC - 1)
    109 #define	EMAC_NEXTTX(x)		(((x) + 1) & EMAC_NTXDESC_MASK)
    110 #define	EMAC_NEXTTXS(x)		(((x) + 1) & EMAC_TXQUEUELEN_MASK)
    111 
    112 /*
    113  * Receive descriptor list size.  There is one Rx channel with up to 256
    114  * hardware descriptors available.  We allocate 64 receive descriptors,
    115  * each with a 2k buffer (MCLBYTES).
    116  */
    117 #define	EMAC_NRXDESC		64
    118 #define	EMAC_NRXDESC_MASK	(EMAC_NRXDESC - 1)
    119 #define	EMAC_NEXTRX(x)		(((x) + 1) & EMAC_NRXDESC_MASK)
    120 #define	EMAC_PREVRX(x)		(((x) - 1) & EMAC_NRXDESC_MASK)
    121 
    122 /*
    123  * Transmit/receive descriptors that are DMA'd to the EMAC.
    124  */
    125 struct emac_control_data {
    126 	struct mal_descriptor ecd_txdesc[EMAC_NTXDESC];
    127 	struct mal_descriptor ecd_rxdesc[EMAC_NRXDESC];
    128 };
    129 
    130 #define	EMAC_CDOFF(x)		offsetof(struct emac_control_data, x)
    131 #define	EMAC_CDTXOFF(x)		EMAC_CDOFF(ecd_txdesc[(x)])
    132 #define	EMAC_CDRXOFF(x)		EMAC_CDOFF(ecd_rxdesc[(x)])
    133 
    134 /*
    135  * Software state for transmit jobs.
    136  */
    137 struct emac_txsoft {
    138 	struct mbuf *txs_mbuf;		/* head of mbuf chain */
    139 	bus_dmamap_t txs_dmamap;	/* our DMA map */
    140 	int txs_firstdesc;		/* first descriptor in packet */
    141 	int txs_lastdesc;		/* last descriptor in packet */
    142 	int txs_ndesc;			/* # of descriptors used */
    143 };
    144 
    145 /*
    146  * Software state for receive descriptors.
    147  */
    148 struct emac_rxsoft {
    149 	struct mbuf *rxs_mbuf;		/* head of mbuf chain */
    150 	bus_dmamap_t rxs_dmamap;	/* our DMA map */
    151 };
    152 
    153 /*
    154  * Software state per device.
    155  */
    156 struct emac_softc {
    157 	device_t sc_dev;		/* generic device information */
    158 	int sc_instance;		/* instance no. */
    159 	bus_space_tag_t sc_st;		/* bus space tag */
    160 	bus_space_handle_t sc_sh;	/* bus space handle */
    161 	bus_dma_tag_t sc_dmat;		/* bus DMA tag */
    162 	struct ethercom sc_ethercom;	/* ethernet common data */
    163 	void *sc_sdhook;		/* shutdown hook */
    164 	void *sc_powerhook;		/* power management hook */
    165 
    166 	struct mii_data sc_mii;		/* MII/media information */
    167 	struct callout sc_callout;	/* tick callout */
    168 
    169 	uint32_t sc_mr1;		/* copy of Mode Register 1 */
    170 	uint32_t sc_stacr_read;		/* Read opcode of STAOPC of STACR */
    171 	uint32_t sc_stacr_write;	/* Write opcode of STAOPC of STACR */
    172 	uint32_t sc_stacr_bits;		/* misc bits of STACR */
    173 	bool sc_stacr_completed;	/* Operation completed of STACR */
    174 	int sc_htsize;			/* Hash Table size */
    175 
    176 	bus_dmamap_t sc_cddmamap;	/* control data dma map */
    177 #define	sc_cddma	sc_cddmamap->dm_segs[0].ds_addr
    178 
    179 	/* Software state for transmit/receive descriptors. */
    180 	struct emac_txsoft sc_txsoft[EMAC_TXQUEUELEN];
    181 	struct emac_rxsoft sc_rxsoft[EMAC_NRXDESC];
    182 
    183 	/* Control data structures. */
    184 	struct emac_control_data *sc_control_data;
    185 #define	sc_txdescs	sc_control_data->ecd_txdesc
    186 #define	sc_rxdescs	sc_control_data->ecd_rxdesc
    187 
    188 #ifdef EMAC_EVENT_COUNTERS
    189 	struct evcnt sc_ev_rxintr;	/* Rx interrupts */
    190 	struct evcnt sc_ev_txintr;	/* Tx interrupts */
    191 	struct evcnt sc_ev_rxde;	/* Rx descriptor interrupts */
    192 	struct evcnt sc_ev_txde;	/* Tx descriptor interrupts */
    193 	struct evcnt sc_ev_intr;	/* General EMAC interrupts */
    194 
    195 	struct evcnt sc_ev_txreap;	/* Calls to Tx descriptor reaper */
    196 	struct evcnt sc_ev_txsstall;	/* Tx stalled due to no txs */
    197 	struct evcnt sc_ev_txdstall;	/* Tx stalled due to no txd */
    198 	struct evcnt sc_ev_txdrop;	/* Tx packets dropped (too many segs) */
    199 	struct evcnt sc_ev_tu;		/* Tx underrun */
    200 #endif /* EMAC_EVENT_COUNTERS */
    201 
    202 	int sc_txfree;			/* number of free Tx descriptors */
    203 	int sc_txnext;			/* next ready Tx descriptor */
    204 
    205 	int sc_txsfree;			/* number of free Tx jobs */
    206 	int sc_txsnext;			/* next ready Tx job */
    207 	int sc_txsdirty;		/* dirty Tx jobs */
    208 
    209 	int sc_rxptr;			/* next ready RX descriptor/descsoft */
    210 
    211 	void (*sc_rmii_enable)(device_t, int);		/* reduced MII enable */
    212 	void (*sc_rmii_disable)(device_t, int);		/* reduced MII disable*/
    213 	void (*sc_rmii_speed)(device_t, int, int);	/* reduced MII speed */
    214 };
    215 
    216 #ifdef EMAC_EVENT_COUNTERS
    217 #define	EMAC_EVCNT_INCR(ev)	(ev)->ev_count++
    218 #else
    219 #define	EMAC_EVCNT_INCR(ev)	/* nothing */
    220 #endif
    221 
    222 #define	EMAC_CDTXADDR(sc, x)	((sc)->sc_cddma + EMAC_CDTXOFF((x)))
    223 #define	EMAC_CDRXADDR(sc, x)	((sc)->sc_cddma + EMAC_CDRXOFF((x)))
    224 
    225 #define	EMAC_CDTXSYNC(sc, x, n, ops)					\
    226 do {									\
    227 	int __x, __n;							\
    228 									\
    229 	__x = (x);							\
    230 	__n = (n);							\
    231 									\
    232 	/* If it will wrap around, sync to the end of the ring. */	\
    233 	if ((__x + __n) > EMAC_NTXDESC) {				\
    234 		bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,	\
    235 		    EMAC_CDTXOFF(__x), sizeof(struct mal_descriptor) *	\
    236 		    (EMAC_NTXDESC - __x), (ops));			\
    237 		__n -= (EMAC_NTXDESC - __x);				\
    238 		__x = 0;						\
    239 	}								\
    240 									\
    241 	/* Now sync whatever is left. */				\
    242 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
    243 	    EMAC_CDTXOFF(__x), sizeof(struct mal_descriptor) * __n, (ops)); \
    244 } while (/*CONSTCOND*/0)
    245 
    246 #define	EMAC_CDRXSYNC(sc, x, ops)					\
    247 do {									\
    248 	bus_dmamap_sync((sc)->sc_dmat, (sc)->sc_cddmamap,		\
    249 	    EMAC_CDRXOFF((x)), sizeof(struct mal_descriptor), (ops));	\
    250 } while (/*CONSTCOND*/0)
    251 
    252 #define	EMAC_INIT_RXDESC(sc, x)						\
    253 do {									\
    254 	struct emac_rxsoft *__rxs = &(sc)->sc_rxsoft[(x)];		\
    255 	struct mal_descriptor *__rxd = &(sc)->sc_rxdescs[(x)];		\
    256 	struct mbuf *__m = __rxs->rxs_mbuf;				\
    257 									\
    258 	/*								\
    259 	 * Note: We scoot the packet forward 2 bytes in the buffer	\
    260 	 * so that the payload after the Ethernet header is aligned	\
    261 	 * to a 4-byte boundary.					\
    262 	 */								\
    263 	__m->m_data = __m->m_ext.ext_buf + 2;				\
    264 									\
    265 	__rxd->md_data = __rxs->rxs_dmamap->dm_segs[0].ds_addr + 2;	\
    266 	__rxd->md_data_len = __m->m_ext.ext_size - 2;			\
    267 	__rxd->md_stat_ctrl = MAL_RX_EMPTY | MAL_RX_INTERRUPT |		\
    268 	    /* Set wrap on last descriptor. */				\
    269 	    (((x) == EMAC_NRXDESC - 1) ? MAL_RX_WRAP : 0);		\
    270 	EMAC_CDRXSYNC((sc), (x), BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE); \
    271 } while (/*CONSTCOND*/0)
    272 
    273 #define	EMAC_WRITE(sc, reg, val) \
    274 	bus_space_write_stream_4((sc)->sc_st, (sc)->sc_sh, (reg), (val))
    275 #define	EMAC_READ(sc, reg) \
    276 	bus_space_read_stream_4((sc)->sc_st, (sc)->sc_sh, (reg))
    277 
    278 #define	EMAC_SET_FILTER(aht, crc) \
    279 do {									\
    280 	(aht)[3 - (((crc) >> 26) >> 4)] |= 1 << (((crc) >> 26) & 0xf);	\
    281 } while (/*CONSTCOND*/0)
    282 #define	EMAC_SET_FILTER256(aht, crc) \
    283 do {									\
    284 	(aht)[7 - (((crc) >> 24) >> 5)] |= 1 << (((crc) >> 24) & 0x1f);	\
    285 } while (/*CONSTCOND*/0)
    286 
    287 static int	emac_match(device_t, cfdata_t, void *);
    288 static void	emac_attach(device_t, device_t, void *);
    289 
    290 static int	emac_intr(void *);
    291 static void	emac_shutdown(void *);
    292 
    293 static void	emac_start(struct ifnet *);
    294 static int	emac_ioctl(struct ifnet *, u_long, void *);
    295 static int	emac_init(struct ifnet *);
    296 static void	emac_stop(struct ifnet *, int);
    297 static void	emac_watchdog(struct ifnet *);
    298 
    299 static int	emac_add_rxbuf(struct emac_softc *, int);
    300 static void	emac_rxdrain(struct emac_softc *);
    301 static int	emac_set_filter(struct emac_softc *);
    302 static int	emac_txreap(struct emac_softc *);
    303 
    304 static void	emac_soft_reset(struct emac_softc *);
    305 static void	emac_smart_reset(struct emac_softc *);
    306 
    307 static int	emac_mii_readreg(device_t, int, int);
    308 static void	emac_mii_writereg(device_t, int, int, int);
    309 static void	emac_mii_statchg(struct ifnet *);
    310 static uint32_t	emac_mii_wait(struct emac_softc *);
    311 static void	emac_mii_tick(void *);
    312 
    313 int		emac_copy_small = 0;
    314 
    315 CFATTACH_DECL_NEW(emac, sizeof(struct emac_softc),
    316     emac_match, emac_attach, NULL, NULL);
    317 
    318 
    319 static int
    320 emac_match(device_t parent, cfdata_t cf, void *aux)
    321 {
    322 	struct opb_attach_args *oaa = aux;
    323 
    324 	/* match only on-chip ethernet devices */
    325 	if (strcmp(oaa->opb_name, cf->cf_name) == 0)
    326 		return 1;
    327 
    328 	return 0;
    329 }
    330 
    331 static void
    332 emac_attach(device_t parent, device_t self, void *aux)
    333 {
    334 	struct opb_attach_args *oaa = aux;
    335 	struct emac_softc *sc = device_private(self);
    336 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
    337 	struct mii_data *mii = &sc->sc_mii;
    338 	const char * xname = device_xname(self);
    339 	bus_dma_segment_t seg;
    340 	int error, i, nseg, opb_freq, opbc, mii_phy = MII_PHY_ANY;
    341 	const uint8_t *enaddr;
    342 	prop_dictionary_t dict = device_properties(self);
    343 	prop_data_t ea;
    344 
    345 	bus_space_map(oaa->opb_bt, oaa->opb_addr, EMAC_NREG, 0, &sc->sc_sh);
    346 
    347 	sc->sc_dev = self;
    348 	sc->sc_instance = oaa->opb_instance;
    349 	sc->sc_st = oaa->opb_bt;
    350 	sc->sc_dmat = oaa->opb_dmat;
    351 
    352 	callout_init(&sc->sc_callout, 0);
    353 
    354 	aprint_naive("\n");
    355 	aprint_normal(": Ethernet Media Access Controller\n");
    356 
    357 	/* Fetch the Ethernet address. */
    358 	ea = prop_dictionary_get(dict, "mac-address");
    359 	if (ea == NULL) {
    360 		aprint_error_dev(self, "unable to get mac-address property\n");
    361 		return;
    362 	}
    363 	KASSERT(prop_object_type(ea) == PROP_TYPE_DATA);
    364 	KASSERT(prop_data_size(ea) == ETHER_ADDR_LEN);
    365 	enaddr = prop_data_data_nocopy(ea);
    366 	aprint_normal_dev(self, "Ethernet address %s\n", ether_sprintf(enaddr));
    367 
    368 #if defined(EMAC_ZMII_PHY) || defined(EMAC_RGMII_PHY)
    369 	/* Fetch the MII offset. */
    370 	prop_dictionary_get_uint32(dict, "mii-phy", &mii_phy);
    371 
    372 #ifdef EMAC_ZMII_PHY
    373 	if (oaa->opb_flags & OPB_FLAGS_EMAC_RMII_ZMII)
    374 		zmii_attach(parent, sc->sc_instance, &sc->sc_rmii_enable,
    375 		    &sc->sc_rmii_disable, &sc->sc_rmii_speed);
    376 #endif
    377 #ifdef EMAC_RGMII_PHY
    378 	if (oaa->opb_flags & OPB_FLAGS_EMAC_RMII_RGMII)
    379 		rgmii_attach(parent, sc->sc_instance, &sc->sc_rmii_enable,
    380 		    &sc->sc_rmii_disable, &sc->sc_rmii_speed);
    381 #endif
    382 #endif
    383 
    384 	/*
    385 	 * Allocate the control data structures, and create and load the
    386 	 * DMA map for it.
    387 	 */
    388 	if ((error = bus_dmamem_alloc(sc->sc_dmat,
    389 	    sizeof(struct emac_control_data), 0, 0, &seg, 1, &nseg, 0)) != 0) {
    390 		aprint_error_dev(self,
    391 		    "unable to allocate control data, error = %d\n", error);
    392 		goto fail_0;
    393 	}
    394 
    395 	if ((error = bus_dmamem_map(sc->sc_dmat, &seg, nseg,
    396 	    sizeof(struct emac_control_data), (void **)&sc->sc_control_data,
    397 	    BUS_DMA_COHERENT)) != 0) {
    398 		aprint_error_dev(self,
    399 		    "unable to map control data, error = %d\n", error);
    400 		goto fail_1;
    401 	}
    402 
    403 	if ((error = bus_dmamap_create(sc->sc_dmat,
    404 	    sizeof(struct emac_control_data), 1,
    405 	    sizeof(struct emac_control_data), 0, 0, &sc->sc_cddmamap)) != 0) {
    406 		aprint_error_dev(self,
    407 		    "unable to create control data DMA map, error = %d\n",
    408 		    error);
    409 		goto fail_2;
    410 	}
    411 
    412 	if ((error = bus_dmamap_load(sc->sc_dmat, sc->sc_cddmamap,
    413 	    sc->sc_control_data, sizeof(struct emac_control_data), NULL,
    414 	    0)) != 0) {
    415 		aprint_error_dev(self,
    416 		    "unable to load control data DMA map, error = %d\n", error);
    417 		goto fail_3;
    418 	}
    419 
    420 	/*
    421 	 * Create the transmit buffer DMA maps.
    422 	 */
    423 	for (i = 0; i < EMAC_TXQUEUELEN; i++) {
    424 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES,
    425 		    EMAC_NTXSEGS, MCLBYTES, 0, 0,
    426 		    &sc->sc_txsoft[i].txs_dmamap)) != 0) {
    427 			aprint_error_dev(self,
    428 			    "unable to create tx DMA map %d, error = %d\n",
    429 			    i, error);
    430 			goto fail_4;
    431 		}
    432 	}
    433 
    434 	/*
    435 	 * Create the receive buffer DMA maps.
    436 	 */
    437 	for (i = 0; i < EMAC_NRXDESC; i++) {
    438 		if ((error = bus_dmamap_create(sc->sc_dmat, MCLBYTES, 1,
    439 		    MCLBYTES, 0, 0, &sc->sc_rxsoft[i].rxs_dmamap)) != 0) {
    440 			aprint_error_dev(self,
    441 			    "unable to create rx DMA map %d, error = %d\n",
    442 			    i, error);
    443 			goto fail_5;
    444 		}
    445 		sc->sc_rxsoft[i].rxs_mbuf = NULL;
    446 	}
    447 
    448 	/* Soft Reset the EMAC.  The chip to a known state. */
    449 	emac_soft_reset(sc);
    450 
    451 	opb_freq = opb_get_frequency();
    452 	switch (opb_freq) {
    453 	case  50000000: opbc =  STACR_OPBC_50MHZ; break;
    454 	case  66666666: opbc =  STACR_OPBC_66MHZ; break;
    455 	case  83333333: opbc =  STACR_OPBC_83MHZ; break;
    456 	case 100000000: opbc = STACR_OPBC_100MHZ; break;
    457 
    458 	default:
    459 		if (opb_freq > 100000000) {
    460 			opbc = STACR_OPBC_A100MHZ;
    461 			break;
    462 		}
    463 		aprint_error_dev(self, "unsupport OPB frequency %dMHz\n",
    464 		    opb_freq / 1000 / 1000);
    465 		goto fail_5;
    466 	}
    467 	if (oaa->opb_flags & OPB_FLAGS_EMAC_GBE) {
    468 		sc->sc_mr1 =
    469 		    MR1_RFS_GBE(MR1__FS_16KB)	|
    470 		    MR1_TFS_GBE(MR1__FS_16KB)	|
    471 		    MR1_TR0_MULTIPLE		|
    472 		    MR1_OBCI(opbc);
    473 		sc->sc_ethercom.ec_capabilities |= ETHERCAP_JUMBO_MTU;
    474 
    475 		if (oaa->opb_flags & OPB_FLAGS_EMAC_STACV2) {
    476 			sc->sc_stacr_read = STACR_STAOPC_READ;
    477 			sc->sc_stacr_write = STACR_STAOPC_WRITE;
    478 			sc->sc_stacr_bits = STACR_OC;
    479 			sc->sc_stacr_completed = false;
    480 		} else {
    481 			sc->sc_stacr_read = STACR_READ;
    482 			sc->sc_stacr_write = STACR_WRITE;
    483 			sc->sc_stacr_completed = true;
    484 		}
    485 	} else {
    486 		/*
    487 		 * Set up Mode Register 1 - set receive and transmit FIFOs to
    488 		 * maximum size, allow transmit of multiple packets (only
    489 		 * channel 0 is used).
    490 		 *
    491 		 * XXX: Allow pause packets??
    492 		 */
    493 		sc->sc_mr1 =
    494 		    MR1_RFS(MR1__FS_4KB) |
    495 		    MR1_TFS(MR1__FS_2KB) |
    496 		    MR1_TR0_MULTIPLE;
    497 
    498 		sc->sc_stacr_read = STACR_READ;
    499 		sc->sc_stacr_write = STACR_WRITE;
    500 		sc->sc_stacr_bits = STACR_OPBC(opbc);
    501 		sc->sc_stacr_completed = true;
    502 	}
    503 
    504 	intr_establish(oaa->opb_irq, IST_LEVEL, IPL_NET, emac_intr, sc);
    505 	mal_intr_establish(sc->sc_instance, sc);
    506 
    507 	if (oaa->opb_flags & OPB_FLAGS_EMAC_HT256)
    508 		sc->sc_htsize = 256;
    509 	else
    510 		sc->sc_htsize = 64;
    511 
    512 	/* Clear all interrupts */
    513 	EMAC_WRITE(sc, EMAC_ISR, ISR_ALL);
    514 
    515 	/*
    516 	 * Initialise the media structures.
    517 	 */
    518 	mii->mii_ifp = ifp;
    519 	mii->mii_readreg = emac_mii_readreg;
    520 	mii->mii_writereg = emac_mii_writereg;
    521 	mii->mii_statchg = emac_mii_statchg;
    522 
    523 	sc->sc_ethercom.ec_mii = mii;
    524 	ifmedia_init(&mii->mii_media, 0, ether_mediachange, ether_mediastatus);
    525 	mii_attach(self, mii, 0xffffffff, mii_phy, MII_OFFSET_ANY,
    526 	    MIIF_DOPAUSE);
    527 	if (LIST_FIRST(&mii->mii_phys) == NULL) {
    528 		ifmedia_add(&mii->mii_media, IFM_ETHER|IFM_NONE, 0, NULL);
    529 		ifmedia_set(&mii->mii_media, IFM_ETHER|IFM_NONE);
    530 	} else
    531 		ifmedia_set(&mii->mii_media, IFM_ETHER|IFM_AUTO);
    532 
    533 	ifp = &sc->sc_ethercom.ec_if;
    534 	strcpy(ifp->if_xname, xname);
    535 	ifp->if_softc = sc;
    536 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
    537 	ifp->if_start = emac_start;
    538 	ifp->if_ioctl = emac_ioctl;
    539 	ifp->if_init = emac_init;
    540 	ifp->if_stop = emac_stop;
    541 	ifp->if_watchdog = emac_watchdog;
    542 	IFQ_SET_READY(&ifp->if_snd);
    543 
    544 	/*
    545 	 * We can support 802.1Q VLAN-sized frames.
    546 	 */
    547 	sc->sc_ethercom.ec_capabilities |= ETHERCAP_VLAN_MTU;
    548 
    549 	/*
    550 	 * Attach the interface.
    551 	 */
    552 	if_attach(ifp);
    553 	ether_ifattach(ifp, enaddr);
    554 
    555 #ifdef EMAC_EVENT_COUNTERS
    556 	/*
    557 	 * Attach the event counters.
    558 	 */
    559 	evcnt_attach_dynamic(&sc->sc_ev_txintr, EVCNT_TYPE_INTR,
    560 	    NULL, xname, "txintr");
    561 	evcnt_attach_dynamic(&sc->sc_ev_rxintr, EVCNT_TYPE_INTR,
    562 	    NULL, xname, "rxintr");
    563 	evcnt_attach_dynamic(&sc->sc_ev_txde, EVCNT_TYPE_INTR,
    564 	    NULL, xname, "txde");
    565 	evcnt_attach_dynamic(&sc->sc_ev_rxde, EVCNT_TYPE_INTR,
    566 	    NULL, xname, "rxde");
    567 	evcnt_attach_dynamic(&sc->sc_ev_intr, EVCNT_TYPE_INTR,
    568 	    NULL, xname, "intr");
    569 
    570 	evcnt_attach_dynamic(&sc->sc_ev_txreap, EVCNT_TYPE_MISC,
    571 	    NULL, xname, "txreap");
    572 	evcnt_attach_dynamic(&sc->sc_ev_txsstall, EVCNT_TYPE_MISC,
    573 	    NULL, xname, "txsstall");
    574 	evcnt_attach_dynamic(&sc->sc_ev_txdstall, EVCNT_TYPE_MISC,
    575 	    NULL, xname, "txdstall");
    576 	evcnt_attach_dynamic(&sc->sc_ev_txdrop, EVCNT_TYPE_MISC,
    577 	    NULL, xname, "txdrop");
    578 	evcnt_attach_dynamic(&sc->sc_ev_tu, EVCNT_TYPE_MISC,
    579 	    NULL, xname, "tu");
    580 #endif /* EMAC_EVENT_COUNTERS */
    581 
    582 	/*
    583 	 * Make sure the interface is shutdown during reboot.
    584 	 */
    585 	sc->sc_sdhook = shutdownhook_establish(emac_shutdown, sc);
    586 	if (sc->sc_sdhook == NULL)
    587 		aprint_error_dev(self,
    588 		    "WARNING: unable to establish shutdown hook\n");
    589 
    590 	return;
    591 
    592 	/*
    593 	 * Free any resources we've allocated during the failed attach
    594 	 * attempt.  Do this in reverse order and fall through.
    595 	 */
    596 fail_5:
    597 	for (i = 0; i < EMAC_NRXDESC; i++) {
    598 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
    599 			bus_dmamap_destroy(sc->sc_dmat,
    600 			    sc->sc_rxsoft[i].rxs_dmamap);
    601 	}
    602 fail_4:
    603 	for (i = 0; i < EMAC_TXQUEUELEN; i++) {
    604 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
    605 			bus_dmamap_destroy(sc->sc_dmat,
    606 			    sc->sc_txsoft[i].txs_dmamap);
    607 	}
    608 	bus_dmamap_unload(sc->sc_dmat, sc->sc_cddmamap);
    609 fail_3:
    610 	bus_dmamap_destroy(sc->sc_dmat, sc->sc_cddmamap);
    611 fail_2:
    612 	bus_dmamem_unmap(sc->sc_dmat, (void *)sc->sc_control_data,
    613 	    sizeof(struct emac_control_data));
    614 fail_1:
    615 	bus_dmamem_free(sc->sc_dmat, &seg, nseg);
    616 fail_0:
    617 	return;
    618 }
    619 
    620 /*
    621  * EMAC General interrupt handler
    622  */
    623 static int
    624 emac_intr(void *arg)
    625 {
    626 	struct emac_softc *sc = arg;
    627 	uint32_t status;
    628 
    629 	EMAC_EVCNT_INCR(&sc->sc_ev_intr);
    630 	status = EMAC_READ(sc, EMAC_ISR);
    631 
    632 	/* Clear the interrupt status bits. */
    633 	EMAC_WRITE(sc, EMAC_ISR, status);
    634 
    635 	return 1;
    636 }
    637 
    638 static void
    639 emac_shutdown(void *arg)
    640 {
    641 	struct emac_softc *sc = arg;
    642 
    643 	emac_stop(&sc->sc_ethercom.ec_if, 0);
    644 }
    645 
    646 
    647 /*
    648  * ifnet interface functions
    649  */
    650 
    651 static void
    652 emac_start(struct ifnet *ifp)
    653 {
    654 	struct emac_softc *sc = ifp->if_softc;
    655 	struct mbuf *m0;
    656 	struct emac_txsoft *txs;
    657 	bus_dmamap_t dmamap;
    658 	int error, firsttx, nexttx, lasttx, ofree, seg;
    659 
    660 	lasttx = 0;	/* XXX gcc */
    661 
    662 	if ((ifp->if_flags & (IFF_RUNNING|IFF_OACTIVE)) != IFF_RUNNING)
    663 		return;
    664 
    665 	/*
    666 	 * Remember the previous number of free descriptors.
    667 	 */
    668 	ofree = sc->sc_txfree;
    669 
    670 	/*
    671 	 * Loop through the send queue, setting up transmit descriptors
    672 	 * until we drain the queue, or use up all available transmit
    673 	 * descriptors.
    674 	 */
    675 	for (;;) {
    676 		/* Grab a packet off the queue. */
    677 		IFQ_POLL(&ifp->if_snd, m0);
    678 		if (m0 == NULL)
    679 			break;
    680 
    681 		/*
    682 		 * Get a work queue entry.  Reclaim used Tx descriptors if
    683 		 * we are running low.
    684 		 */
    685 		if (sc->sc_txsfree < EMAC_TXQUEUE_GC) {
    686 			emac_txreap(sc);
    687 			if (sc->sc_txsfree == 0) {
    688 				EMAC_EVCNT_INCR(&sc->sc_ev_txsstall);
    689 				break;
    690 			}
    691 		}
    692 
    693 		txs = &sc->sc_txsoft[sc->sc_txsnext];
    694 		dmamap = txs->txs_dmamap;
    695 
    696 		/*
    697 		 * Load the DMA map.  If this fails, the packet either
    698 		 * didn't fit in the alloted number of segments, or we
    699 		 * were short on resources.  In this case, we'll copy
    700 		 * and try again.
    701 		 */
    702 		error = bus_dmamap_load_mbuf(sc->sc_dmat, dmamap, m0,
    703 		    BUS_DMA_WRITE|BUS_DMA_NOWAIT);
    704 		if (error) {
    705 			if (error == EFBIG) {
    706 				EMAC_EVCNT_INCR(&sc->sc_ev_txdrop);
    707 				aprint_error_ifnet(ifp,
    708 				    "Tx packet consumes too many "
    709 				    "DMA segments, dropping...\n");
    710 				    IFQ_DEQUEUE(&ifp->if_snd, m0);
    711 				    m_freem(m0);
    712 				    continue;
    713 			}
    714 			/* Short on resources, just stop for now. */
    715 			break;
    716 		}
    717 
    718 		/*
    719 		 * Ensure we have enough descriptors free to describe
    720 		 * the packet.
    721 		 */
    722 		if (dmamap->dm_nsegs > sc->sc_txfree) {
    723 			/*
    724 			 * Not enough free descriptors to transmit this
    725 			 * packet.  We haven't committed anything yet,
    726 			 * so just unload the DMA map, put the packet
    727 			 * back on the queue, and punt.  Notify the upper
    728 			 * layer that there are not more slots left.
    729 			 *
    730 			 */
    731 			ifp->if_flags |= IFF_OACTIVE;
    732 			bus_dmamap_unload(sc->sc_dmat, dmamap);
    733 			EMAC_EVCNT_INCR(&sc->sc_ev_txdstall);
    734 			break;
    735 		}
    736 
    737 		IFQ_DEQUEUE(&ifp->if_snd, m0);
    738 
    739 		/*
    740 		 * WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
    741 		 */
    742 
    743 		/* Sync the DMA map. */
    744 		bus_dmamap_sync(sc->sc_dmat, dmamap, 0, dmamap->dm_mapsize,
    745 		    BUS_DMASYNC_PREWRITE);
    746 
    747 		/*
    748 		 * Store a pointer to the packet so that we can free it
    749 		 * later.
    750 		 */
    751 		txs->txs_mbuf = m0;
    752 		txs->txs_firstdesc = sc->sc_txnext;
    753 		txs->txs_ndesc = dmamap->dm_nsegs;
    754 
    755 		/*
    756 		 * Initialize the transmit descriptor.
    757 		 */
    758 		firsttx = sc->sc_txnext;
    759 		for (nexttx = sc->sc_txnext, seg = 0;
    760 		     seg < dmamap->dm_nsegs;
    761 		     seg++, nexttx = EMAC_NEXTTX(nexttx)) {
    762 			struct mal_descriptor *txdesc =
    763 			    &sc->sc_txdescs[nexttx];
    764 
    765 			/*
    766 			 * If this is the first descriptor we're
    767 			 * enqueueing, don't set the TX_READY bit just
    768 			 * yet.  That could cause a race condition.
    769 			 * We'll do it below.
    770 			 */
    771 			txdesc->md_data = dmamap->dm_segs[seg].ds_addr;
    772 			txdesc->md_data_len = dmamap->dm_segs[seg].ds_len;
    773 			txdesc->md_stat_ctrl =
    774 			    (txdesc->md_stat_ctrl & MAL_TX_WRAP) |
    775 			    (nexttx == firsttx ? 0 : MAL_TX_READY) |
    776 			    EMAC_TXC_GFCS | EMAC_TXC_GPAD;
    777 			lasttx = nexttx;
    778 		}
    779 
    780 		/* Set the LAST bit on the last segment. */
    781 		sc->sc_txdescs[lasttx].md_stat_ctrl |= MAL_TX_LAST;
    782 
    783 		/*
    784 		 * Set up last segment descriptor to send an interrupt after
    785 		 * that descriptor is transmitted, and bypass existing Tx
    786 		 * descriptor reaping method (for now...).
    787 		 */
    788 		sc->sc_txdescs[lasttx].md_stat_ctrl |= MAL_TX_INTERRUPT;
    789 
    790 
    791 		txs->txs_lastdesc = lasttx;
    792 
    793 		/* Sync the descriptors we're using. */
    794 		EMAC_CDTXSYNC(sc, sc->sc_txnext, dmamap->dm_nsegs,
    795 		    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
    796 
    797 		/*
    798 		 * The entire packet chain is set up.  Give the
    799 		 * first descriptor to the chip now.
    800 		 */
    801 		sc->sc_txdescs[firsttx].md_stat_ctrl |= MAL_TX_READY;
    802 		EMAC_CDTXSYNC(sc, firsttx, 1,
    803 		    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
    804 		/*
    805 		 * Tell the EMAC that a new packet is available.
    806 		 */
    807 		EMAC_WRITE(sc, EMAC_TMR0, TMR0_GNP0 | TMR0_TFAE_2);
    808 
    809 		/* Advance the tx pointer. */
    810 		sc->sc_txfree -= txs->txs_ndesc;
    811 		sc->sc_txnext = nexttx;
    812 
    813 		sc->sc_txsfree--;
    814 		sc->sc_txsnext = EMAC_NEXTTXS(sc->sc_txsnext);
    815 
    816 		/*
    817 		 * Pass the packet to any BPF listeners.
    818 		 */
    819 		bpf_mtap(ifp, m0);
    820 	}
    821 
    822 	if (sc->sc_txfree == 0)
    823 		/* No more slots left; notify upper layer. */
    824 		ifp->if_flags |= IFF_OACTIVE;
    825 
    826 	if (sc->sc_txfree != ofree)
    827 		/* Set a watchdog timer in case the chip flakes out. */
    828 		ifp->if_timer = 5;
    829 }
    830 
    831 static int
    832 emac_ioctl(struct ifnet *ifp, u_long cmd, void *data)
    833 {
    834 	struct emac_softc *sc = ifp->if_softc;
    835 	int s, error;
    836 
    837 	s = splnet();
    838 
    839 	switch (cmd) {
    840 	case SIOCSIFMTU:
    841 	{
    842 		struct ifreq *ifr = (struct ifreq *)data;
    843 		int maxmtu;
    844 
    845 		if (sc->sc_ethercom.ec_capabilities & ETHERCAP_JUMBO_MTU)
    846 			maxmtu = EMAC_MAX_MTU;
    847 		else
    848 			maxmtu = ETHERMTU;
    849 
    850 		if (ifr->ifr_mtu < ETHERMIN || ifr->ifr_mtu > maxmtu)
    851 			error = EINVAL;
    852 		else if ((error = ifioctl_common(ifp, cmd, data)) != ENETRESET)
    853 			break;
    854 		else if (ifp->if_flags & IFF_UP)
    855 			error = emac_init(ifp);
    856 		else
    857 			error = 0;
    858 		break;
    859 	}
    860 
    861 	default:
    862 		error = ether_ioctl(ifp, cmd, data);
    863 		if (error == ENETRESET) {
    864 			/*
    865 			 * Multicast list has changed; set the hardware filter
    866 			 * accordingly.
    867 			 */
    868 			if (ifp->if_flags & IFF_RUNNING)
    869 				error = emac_set_filter(sc);
    870 			else
    871 				error = 0;
    872 		}
    873 	}
    874 
    875 	/* try to get more packets going */
    876 	emac_start(ifp);
    877 
    878 	splx(s);
    879 	return error;
    880 }
    881 
    882 static int
    883 emac_init(struct ifnet *ifp)
    884 {
    885 	struct emac_softc *sc = ifp->if_softc;
    886 	struct emac_rxsoft *rxs;
    887 	const uint8_t *enaddr = CLLADDR(ifp->if_sadl);
    888 	int error, i;
    889 
    890 	error = 0;
    891 
    892 	/* Cancel any pending I/O. */
    893 	emac_stop(ifp, 0);
    894 
    895 	/* Reset the chip to a known state. */
    896 	emac_soft_reset(sc);
    897 
    898 	/*
    899 	 * Initialise the transmit descriptor ring.
    900 	 */
    901 	memset(sc->sc_txdescs, 0, sizeof(sc->sc_txdescs));
    902 	/* set wrap on last descriptor */
    903 	sc->sc_txdescs[EMAC_NTXDESC - 1].md_stat_ctrl |= MAL_TX_WRAP;
    904 	EMAC_CDTXSYNC(sc, 0, EMAC_NTXDESC,
    905 	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
    906 	sc->sc_txfree = EMAC_NTXDESC;
    907 	sc->sc_txnext = 0;
    908 
    909 	/*
    910 	 * Initialise the transmit job descriptors.
    911 	 */
    912 	for (i = 0; i < EMAC_TXQUEUELEN; i++)
    913 		sc->sc_txsoft[i].txs_mbuf = NULL;
    914 	sc->sc_txsfree = EMAC_TXQUEUELEN;
    915 	sc->sc_txsnext = 0;
    916 	sc->sc_txsdirty = 0;
    917 
    918 	/*
    919 	 * Initialise the receiver descriptor and receive job
    920 	 * descriptor rings.
    921 	 */
    922 	for (i = 0; i < EMAC_NRXDESC; i++) {
    923 		rxs = &sc->sc_rxsoft[i];
    924 		if (rxs->rxs_mbuf == NULL) {
    925 			if ((error = emac_add_rxbuf(sc, i)) != 0) {
    926 				aprint_error_ifnet(ifp,
    927 				    "unable to allocate or map rx buffer %d,"
    928 				    " error = %d\n",
    929 				    i, error);
    930 				/*
    931 				 * XXX Should attempt to run with fewer receive
    932 				 * XXX buffers instead of just failing.
    933 				 */
    934 				emac_rxdrain(sc);
    935 				goto out;
    936 			}
    937 		} else
    938 			EMAC_INIT_RXDESC(sc, i);
    939 	}
    940 	sc->sc_rxptr = 0;
    941 
    942 	/*
    943 	 * Set the current media.
    944 	 */
    945 	if ((error = ether_mediachange(ifp)) != 0)
    946 		goto out;
    947 
    948 	/*
    949 	 * Load the MAC address.
    950 	 */
    951 	EMAC_WRITE(sc, EMAC_IAHR, enaddr[0] << 8 | enaddr[1]);
    952 	EMAC_WRITE(sc, EMAC_IALR,
    953 	    enaddr[2] << 24 | enaddr[3] << 16 | enaddr[4] << 8 | enaddr[5]);
    954 
    955 	/* Enable the transmit and receive channel on the MAL. */
    956 	error = mal_start(sc->sc_instance,
    957 	    EMAC_CDTXADDR(sc, 0), EMAC_CDRXADDR(sc, 0));
    958 	if (error)
    959 		goto out;
    960 
    961 	sc->sc_mr1 &= ~MR1_JPSM;
    962 	if (ifp->if_mtu > ETHERMTU)
    963 		/* Enable Jumbo Packet Support Mode */
    964 		sc->sc_mr1 |= MR1_JPSM;
    965 
    966 	/* Set fifos, media modes. */
    967 	EMAC_WRITE(sc, EMAC_MR1, sc->sc_mr1);
    968 
    969 	/*
    970 	 * Enable Individual and (possibly) Broadcast Address modes,
    971 	 * runt packets, and strip padding.
    972 	 */
    973 	EMAC_WRITE(sc, EMAC_RMR, RMR_IAE | RMR_RRP | RMR_SP | RMR_TFAE_2 |
    974 	    (ifp->if_flags & IFF_PROMISC ? RMR_PME : 0) |
    975 	    (ifp->if_flags & IFF_BROADCAST ? RMR_BAE : 0));
    976 
    977 	/*
    978 	 * Set multicast filter.
    979 	 */
    980 	emac_set_filter(sc);
    981 
    982 	/*
    983 	 * Set low- and urgent-priority request thresholds.
    984 	 */
    985 	EMAC_WRITE(sc, EMAC_TMR1,
    986 	    ((7 << TMR1_TLR_SHIFT) & TMR1_TLR_MASK) | /* 16 word burst */
    987 	    ((15 << TMR1_TUR_SHIFT) & TMR1_TUR_MASK));
    988 	/*
    989 	 * Set Transmit Request Threshold Register.
    990 	 */
    991 	EMAC_WRITE(sc, EMAC_TRTR, TRTR_256);
    992 
    993 	/*
    994 	 * Set high and low receive watermarks.
    995 	 */
    996 	EMAC_WRITE(sc, EMAC_RWMR,
    997 	    30 << RWMR_RLWM_SHIFT | 64 << RWMR_RLWM_SHIFT);
    998 
    999 	/*
   1000 	 * Set frame gap.
   1001 	 */
   1002 	EMAC_WRITE(sc, EMAC_IPGVR, 8);
   1003 
   1004 	/*
   1005 	 * Set interrupt status enable bits for EMAC.
   1006 	 */
   1007 	EMAC_WRITE(sc, EMAC_ISER,
   1008 	    ISR_TXPE |		/* TX Parity Error */
   1009 	    ISR_RXPE |		/* RX Parity Error */
   1010 	    ISR_TXUE |		/* TX Underrun Event */
   1011 	    ISR_RXOE |		/* RX Overrun Event */
   1012 	    ISR_OVR  |		/* Overrun Error */
   1013 	    ISR_PP   |		/* Pause Packet */
   1014 	    ISR_BP   |		/* Bad Packet */
   1015 	    ISR_RP   |		/* Runt Packet */
   1016 	    ISR_SE   |		/* Short Event */
   1017 	    ISR_ALE  |		/* Alignment Error */
   1018 	    ISR_BFCS |		/* Bad FCS */
   1019 	    ISR_PTLE |		/* Packet Too Long Error */
   1020 	    ISR_ORE  |		/* Out of Range Error */
   1021 	    ISR_IRE  |		/* In Range Error */
   1022 	    ISR_SE0  |		/* Signal Quality Error 0 (SQE) */
   1023 	    ISR_TE0  |		/* Transmit Error 0 */
   1024 	    ISR_MOS  |		/* MMA Operation Succeeded */
   1025 	    ISR_MOF);		/* MMA Operation Failed */
   1026 
   1027 	/*
   1028 	 * Enable the transmit and receive channel on the EMAC.
   1029 	 */
   1030 	EMAC_WRITE(sc, EMAC_MR0, MR0_TXE | MR0_RXE);
   1031 
   1032 	/*
   1033 	 * Start the one second MII clock.
   1034 	 */
   1035 	callout_reset(&sc->sc_callout, hz, emac_mii_tick, sc);
   1036 
   1037 	/*
   1038 	 * ... all done!
   1039 	 */
   1040 	ifp->if_flags |= IFF_RUNNING;
   1041 	ifp->if_flags &= ~IFF_OACTIVE;
   1042 
   1043  out:
   1044 	if (error) {
   1045 		ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
   1046 		ifp->if_timer = 0;
   1047 		aprint_error_ifnet(ifp, "interface not running\n");
   1048 	}
   1049 	return error;
   1050 }
   1051 
   1052 static void
   1053 emac_stop(struct ifnet *ifp, int disable)
   1054 {
   1055 	struct emac_softc *sc = ifp->if_softc;
   1056 	struct emac_txsoft *txs;
   1057 	int i;
   1058 
   1059 	/* Stop the one second clock. */
   1060 	callout_stop(&sc->sc_callout);
   1061 
   1062 	/* Down the MII */
   1063 	mii_down(&sc->sc_mii);
   1064 
   1065 	/* Disable interrupts. */
   1066 	EMAC_WRITE(sc, EMAC_ISER, 0);
   1067 
   1068 	/* Disable the receive and transmit channels. */
   1069 	mal_stop(sc->sc_instance);
   1070 
   1071 	/* Disable the transmit enable and receive MACs. */
   1072 	EMAC_WRITE(sc, EMAC_MR0,
   1073 	    EMAC_READ(sc, EMAC_MR0) & ~(MR0_TXE | MR0_RXE));
   1074 
   1075 	/* Release any queued transmit buffers. */
   1076 	for (i = 0; i < EMAC_TXQUEUELEN; i++) {
   1077 		txs = &sc->sc_txsoft[i];
   1078 		if (txs->txs_mbuf != NULL) {
   1079 			bus_dmamap_unload(sc->sc_dmat, txs->txs_dmamap);
   1080 			m_freem(txs->txs_mbuf);
   1081 			txs->txs_mbuf = NULL;
   1082 		}
   1083 	}
   1084 
   1085 	if (disable)
   1086 		emac_rxdrain(sc);
   1087 
   1088 	/*
   1089 	 * Mark the interface down and cancel the watchdog timer.
   1090 	 */
   1091 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
   1092 	ifp->if_timer = 0;
   1093 }
   1094 
   1095 static void
   1096 emac_watchdog(struct ifnet *ifp)
   1097 {
   1098 	struct emac_softc *sc = ifp->if_softc;
   1099 
   1100 	/*
   1101 	 * Since we're not interrupting every packet, sweep
   1102 	 * up before we report an error.
   1103 	 */
   1104 	emac_txreap(sc);
   1105 
   1106 	if (sc->sc_txfree != EMAC_NTXDESC) {
   1107 		aprint_error_ifnet(ifp,
   1108 		    "device timeout (txfree %d txsfree %d txnext %d)\n",
   1109 		    sc->sc_txfree, sc->sc_txsfree, sc->sc_txnext);
   1110 		ifp->if_oerrors++;
   1111 
   1112 		/* Reset the interface. */
   1113 		(void)emac_init(ifp);
   1114 	} else if (ifp->if_flags & IFF_DEBUG)
   1115 		aprint_error_ifnet(ifp, "recovered from device timeout\n");
   1116 
   1117 	/* try to get more packets going */
   1118 	emac_start(ifp);
   1119 }
   1120 
   1121 static int
   1122 emac_add_rxbuf(struct emac_softc *sc, int idx)
   1123 {
   1124 	struct emac_rxsoft *rxs = &sc->sc_rxsoft[idx];
   1125 	struct mbuf *m;
   1126 	int error;
   1127 
   1128 	MGETHDR(m, M_DONTWAIT, MT_DATA);
   1129 	if (m == NULL)
   1130 		return ENOBUFS;
   1131 
   1132 	MCLGET(m, M_DONTWAIT);
   1133 	if ((m->m_flags & M_EXT) == 0) {
   1134 		m_freem(m);
   1135 		return ENOBUFS;
   1136 	}
   1137 
   1138 	if (rxs->rxs_mbuf != NULL)
   1139 		bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
   1140 
   1141 	rxs->rxs_mbuf = m;
   1142 
   1143 	error = bus_dmamap_load(sc->sc_dmat, rxs->rxs_dmamap,
   1144 	    m->m_ext.ext_buf, m->m_ext.ext_size, NULL, BUS_DMA_NOWAIT);
   1145 	if (error) {
   1146 		aprint_error_dev(sc->sc_dev,
   1147 		    "can't load rx DMA map %d, error = %d\n", idx, error);
   1148 		panic("emac_add_rxbuf");		/* XXX */
   1149 	}
   1150 
   1151 	bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
   1152 	    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
   1153 
   1154 	EMAC_INIT_RXDESC(sc, idx);
   1155 
   1156 	return 0;
   1157 }
   1158 
   1159 static void
   1160 emac_rxdrain(struct emac_softc *sc)
   1161 {
   1162 	struct emac_rxsoft *rxs;
   1163 	int i;
   1164 
   1165 	for (i = 0; i < EMAC_NRXDESC; i++) {
   1166 		rxs = &sc->sc_rxsoft[i];
   1167 		if (rxs->rxs_mbuf != NULL) {
   1168 			bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
   1169 			m_freem(rxs->rxs_mbuf);
   1170 			rxs->rxs_mbuf = NULL;
   1171 		}
   1172 	}
   1173 }
   1174 
   1175 static int
   1176 emac_set_filter(struct emac_softc *sc)
   1177 {
   1178 	struct ether_multistep step;
   1179 	struct ether_multi *enm;
   1180 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
   1181 	uint32_t rmr, crc, mask, tmp, reg, gaht[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };
   1182 	int regs, cnt = 0, i;
   1183 
   1184 	if (sc->sc_htsize == 256) {
   1185 		reg = EMAC_GAHT256(0);
   1186 		regs = 8;
   1187 	} else {
   1188 		reg = EMAC_GAHT64(0);
   1189 		regs = 4;
   1190 	}
   1191 	mask = (1ULL << (sc->sc_htsize / regs)) - 1;
   1192 
   1193 	rmr = EMAC_READ(sc, EMAC_RMR);
   1194 	rmr &= ~(RMR_PMME | RMR_MAE);
   1195 	ifp->if_flags &= ~IFF_ALLMULTI;
   1196 
   1197 	ETHER_FIRST_MULTI(step, &sc->sc_ethercom, enm);
   1198 	while (enm != NULL) {
   1199 		if (memcmp(enm->enm_addrlo,
   1200 		    enm->enm_addrhi, ETHER_ADDR_LEN) != 0) {
   1201 			/*
   1202 			 * We must listen to a range of multicast addresses.
   1203 			 * For now, just accept all multicasts, rather than
   1204 			 * trying to set only those filter bits needed to match
   1205 			 * the range.  (At this time, the only use of address
   1206 			 * ranges is for IP multicast routing, for which the
   1207 			 * range is big enough to require all bits set.)
   1208 			 */
   1209 			gaht[0] = gaht[1] = gaht[2] = gaht[3] =
   1210 			    gaht[4] = gaht[5] = gaht[6] = gaht[7] = mask;
   1211 			break;
   1212 		}
   1213 
   1214 		crc = ether_crc32_be(enm->enm_addrlo, ETHER_ADDR_LEN);
   1215 
   1216 		if (sc->sc_htsize == 256)
   1217 			EMAC_SET_FILTER256(gaht, crc);
   1218 		else
   1219 			EMAC_SET_FILTER(gaht, crc);
   1220 
   1221 		ETHER_NEXT_MULTI(step, enm);
   1222 		cnt++;
   1223 	}
   1224 
   1225 	for (i = 1, tmp = gaht[0]; i < regs; i++)
   1226 		tmp &= gaht[i];
   1227 	if (tmp == mask) {
   1228 		/* All categories are true. */
   1229 		ifp->if_flags |= IFF_ALLMULTI;
   1230 		rmr |= RMR_PMME;
   1231 	} else if (cnt != 0) {
   1232 		/* Some categories are true. */
   1233 		for (i = 0; i < regs; i++)
   1234 			EMAC_WRITE(sc, reg + (i << 2), gaht[i]);
   1235 		rmr |= RMR_MAE;
   1236 	}
   1237 	EMAC_WRITE(sc, EMAC_RMR, rmr);
   1238 
   1239 	return 0;
   1240 }
   1241 
   1242 /*
   1243  * Reap completed Tx descriptors.
   1244  */
   1245 static int
   1246 emac_txreap(struct emac_softc *sc)
   1247 {
   1248 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
   1249 	struct emac_txsoft *txs;
   1250 	int handled, i;
   1251 	uint32_t txstat;
   1252 
   1253 	EMAC_EVCNT_INCR(&sc->sc_ev_txreap);
   1254 	handled = 0;
   1255 
   1256 	ifp->if_flags &= ~IFF_OACTIVE;
   1257 
   1258 	/*
   1259 	 * Go through our Tx list and free mbufs for those
   1260 	 * frames that have been transmitted.
   1261 	 */
   1262 	for (i = sc->sc_txsdirty; sc->sc_txsfree != EMAC_TXQUEUELEN;
   1263 	    i = EMAC_NEXTTXS(i), sc->sc_txsfree++) {
   1264 		txs = &sc->sc_txsoft[i];
   1265 
   1266 		EMAC_CDTXSYNC(sc, txs->txs_lastdesc,
   1267 		    txs->txs_dmamap->dm_nsegs,
   1268 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
   1269 
   1270 		txstat = sc->sc_txdescs[txs->txs_lastdesc].md_stat_ctrl;
   1271 		if (txstat & MAL_TX_READY)
   1272 			break;
   1273 
   1274 		handled = 1;
   1275 
   1276 		/*
   1277 		 * Check for errors and collisions.
   1278 		 */
   1279 		if (txstat & (EMAC_TXS_UR | EMAC_TXS_ED))
   1280 			ifp->if_oerrors++;
   1281 
   1282 #ifdef EMAC_EVENT_COUNTERS
   1283 		if (txstat & EMAC_TXS_UR)
   1284 			EMAC_EVCNT_INCR(&sc->sc_ev_tu);
   1285 #endif /* EMAC_EVENT_COUNTERS */
   1286 
   1287 		if (txstat &
   1288 		    (EMAC_TXS_EC | EMAC_TXS_MC | EMAC_TXS_SC | EMAC_TXS_LC)) {
   1289 			if (txstat & EMAC_TXS_EC)
   1290 				ifp->if_collisions += 16;
   1291 			else if (txstat & EMAC_TXS_MC)
   1292 				ifp->if_collisions += 2;	/* XXX? */
   1293 			else if (txstat & EMAC_TXS_SC)
   1294 				ifp->if_collisions++;
   1295 			if (txstat & EMAC_TXS_LC)
   1296 				ifp->if_collisions++;
   1297 		} else
   1298 			ifp->if_opackets++;
   1299 
   1300 		if (ifp->if_flags & IFF_DEBUG) {
   1301 			if (txstat & EMAC_TXS_ED)
   1302 				aprint_error_ifnet(ifp, "excessive deferral\n");
   1303 			if (txstat & EMAC_TXS_EC)
   1304 				aprint_error_ifnet(ifp,
   1305 				    "excessive collisions\n");
   1306 		}
   1307 
   1308 		sc->sc_txfree += txs->txs_ndesc;
   1309 		bus_dmamap_sync(sc->sc_dmat, txs->txs_dmamap,
   1310 		    0, txs->txs_dmamap->dm_mapsize, BUS_DMASYNC_POSTWRITE);
   1311 		bus_dmamap_unload(sc->sc_dmat, txs->txs_dmamap);
   1312 		m_freem(txs->txs_mbuf);
   1313 		txs->txs_mbuf = NULL;
   1314 	}
   1315 
   1316 	/* Update the dirty transmit buffer pointer. */
   1317 	sc->sc_txsdirty = i;
   1318 
   1319 	/*
   1320 	 * If there are no more pending transmissions, cancel the watchdog
   1321 	 * timer.
   1322 	 */
   1323 	if (sc->sc_txsfree == EMAC_TXQUEUELEN)
   1324 		ifp->if_timer = 0;
   1325 
   1326 	return handled;
   1327 }
   1328 
   1329 
   1330 /*
   1331  * Reset functions
   1332  */
   1333 
   1334 static void
   1335 emac_soft_reset(struct emac_softc *sc)
   1336 {
   1337 	uint32_t sdr;
   1338 	int t = 0;
   1339 
   1340 	/*
   1341 	 * The PHY must provide a TX Clk in order perform a soft reset the
   1342 	 * EMAC.  If none is present, select the internal clock,
   1343 	 * SDR0_MFR[E0CS,E1CS].  After the soft reset, select the external
   1344 	 * clock.
   1345 	 */
   1346 
   1347 	sdr = mfsdr(DCR_SDR0_MFR);
   1348 	sdr |= SDR0_MFR_ECS(sc->sc_instance);
   1349 	mtsdr(DCR_SDR0_MFR, sdr);
   1350 
   1351 	EMAC_WRITE(sc, EMAC_MR0, MR0_SRST);
   1352 
   1353 	sdr = mfsdr(DCR_SDR0_MFR);
   1354 	sdr &= ~SDR0_MFR_ECS(sc->sc_instance);
   1355 	mtsdr(DCR_SDR0_MFR, sdr);
   1356 
   1357 	delay(5);
   1358 
   1359 	/* wait finish */
   1360 	while (EMAC_READ(sc, EMAC_MR0) & MR0_SRST) {
   1361 		if (++t == 1000000 /* 1sec XXXXX */) {
   1362 			aprint_error_dev(sc->sc_dev, "Soft Reset failed\n");
   1363 			return;
   1364 		}
   1365 		delay(1);
   1366 	}
   1367 }
   1368 
   1369 static void
   1370 emac_smart_reset(struct emac_softc *sc)
   1371 {
   1372 	uint32_t mr0;
   1373 	int t = 0;
   1374 
   1375 	mr0 = EMAC_READ(sc, EMAC_MR0);
   1376 	if (mr0 & (MR0_TXE | MR0_RXE)) {
   1377 		mr0 &= ~(MR0_TXE | MR0_RXE);
   1378 		EMAC_WRITE(sc, EMAC_MR0, mr0);
   1379 
   1380 		/* wait idel state */
   1381 		while ((EMAC_READ(sc, EMAC_MR0) & (MR0_TXI | MR0_RXI)) !=
   1382 		    (MR0_TXI | MR0_RXI)) {
   1383 			if (++t == 1000000 /* 1sec XXXXX */) {
   1384 				aprint_error_dev(sc->sc_dev,
   1385 				    "Smart Reset failed\n");
   1386 				return;
   1387 			}
   1388 			delay(1);
   1389 		}
   1390 	}
   1391 }
   1392 
   1393 
   1394 /*
   1395  * MII related functions
   1396  */
   1397 
   1398 static int
   1399 emac_mii_readreg(device_t self, int phy, int reg)
   1400 {
   1401 	struct emac_softc *sc = device_private(self);
   1402 	uint32_t sta_reg;
   1403 
   1404 	if (sc->sc_rmii_enable)
   1405 		sc->sc_rmii_enable(device_parent(self), sc->sc_instance);
   1406 
   1407 	/* wait for PHY data transfer to complete */
   1408 	if (emac_mii_wait(sc))
   1409 		goto fail;
   1410 
   1411 	sta_reg =
   1412 	    sc->sc_stacr_read		|
   1413 	    (reg << STACR_PRA_SHIFT)	|
   1414 	    (phy << STACR_PCDA_SHIFT)	|
   1415 	    sc->sc_stacr_bits;
   1416 	EMAC_WRITE(sc, EMAC_STACR, sta_reg);
   1417 
   1418 	if (emac_mii_wait(sc))
   1419 		goto fail;
   1420 	sta_reg = EMAC_READ(sc, EMAC_STACR);
   1421 
   1422 	if (sc->sc_rmii_disable)
   1423 		sc->sc_rmii_disable(device_parent(self), sc->sc_instance);
   1424 
   1425 	if (sta_reg & STACR_PHYE)
   1426 		return 0;
   1427 	return sta_reg >> STACR_PHYD_SHIFT;
   1428 
   1429 fail:
   1430 	if (sc->sc_rmii_disable)
   1431 		sc->sc_rmii_disable(device_parent(self), sc->sc_instance);
   1432 	return 0;
   1433 }
   1434 
   1435 static void
   1436 emac_mii_writereg(device_t self, int phy, int reg, int val)
   1437 {
   1438 	struct emac_softc *sc = device_private(self);
   1439 	uint32_t sta_reg;
   1440 
   1441 	if (sc->sc_rmii_enable)
   1442 		sc->sc_rmii_enable(device_parent(self), sc->sc_instance);
   1443 
   1444 	/* wait for PHY data transfer to complete */
   1445 	if (emac_mii_wait(sc))
   1446 		goto out;
   1447 
   1448 	sta_reg =
   1449 	    (val << STACR_PHYD_SHIFT)	|
   1450 	    sc->sc_stacr_write		|
   1451 	    (reg << STACR_PRA_SHIFT)	|
   1452 	    (phy << STACR_PCDA_SHIFT)	|
   1453 	    sc->sc_stacr_bits;
   1454 	EMAC_WRITE(sc, EMAC_STACR, sta_reg);
   1455 
   1456 	if (emac_mii_wait(sc))
   1457 		goto out;
   1458 	if (EMAC_READ(sc, EMAC_STACR) & STACR_PHYE)
   1459 		aprint_error_dev(sc->sc_dev, "MII PHY Error\n");
   1460 
   1461 out:
   1462 	if (sc->sc_rmii_disable)
   1463 		sc->sc_rmii_disable(device_parent(self), sc->sc_instance);
   1464 }
   1465 
   1466 static void
   1467 emac_mii_statchg(struct ifnet *ifp)
   1468 {
   1469 	struct emac_softc *sc = ifp->if_softc;
   1470 	struct mii_data *mii = &sc->sc_mii;
   1471 
   1472 	/*
   1473 	 * MR1 can only be written immediately after a reset...
   1474 	 */
   1475 	emac_smart_reset(sc);
   1476 
   1477 	sc->sc_mr1 &= ~(MR1_FDE | MR1_ILE | MR1_EIFC | MR1_MF_MASK | MR1_IST);
   1478 	if (mii->mii_media_active & IFM_FDX)
   1479 		sc->sc_mr1 |= (MR1_FDE | MR1_EIFC | MR1_IST);
   1480 	if (mii->mii_media_active & IFM_FLOW)
   1481 		sc->sc_mr1 |= MR1_EIFC;
   1482 	if (mii->mii_media_active & IFM_LOOP)
   1483 		sc->sc_mr1 |= MR1_ILE;
   1484 	switch (IFM_SUBTYPE(mii->mii_media_active)) {
   1485 	case IFM_1000_T:
   1486 		sc->sc_mr1 |= (MR1_MF_1000MBS | MR1_IST);
   1487 		break;
   1488 
   1489 	case IFM_100_TX:
   1490 		sc->sc_mr1 |= (MR1_MF_100MBS | MR1_IST);
   1491 		break;
   1492 
   1493 	case IFM_10_T:
   1494 		sc->sc_mr1 |= MR1_MF_10MBS;
   1495 		break;
   1496 
   1497 	case IFM_NONE:
   1498 		break;
   1499 
   1500 	default:
   1501 		aprint_error_dev(sc->sc_dev, "unknown sub-type %d\n",
   1502 		    IFM_SUBTYPE(mii->mii_media_active));
   1503 		break;
   1504 	}
   1505 	if (sc->sc_rmii_speed)
   1506 		sc->sc_rmii_speed(device_parent(sc->sc_dev), sc->sc_instance,
   1507 		    IFM_SUBTYPE(mii->mii_media_active));
   1508 
   1509 	EMAC_WRITE(sc, EMAC_MR1, sc->sc_mr1);
   1510 
   1511 	/* Enable TX and RX if already RUNNING */
   1512 	if (ifp->if_flags & IFF_RUNNING)
   1513 		EMAC_WRITE(sc, EMAC_MR0, MR0_TXE | MR0_RXE);
   1514 }
   1515 
   1516 static uint32_t
   1517 emac_mii_wait(struct emac_softc *sc)
   1518 {
   1519 	int i;
   1520 	uint32_t oc;
   1521 
   1522 	/* wait for PHY data transfer to complete */
   1523 	i = 0;
   1524 	oc = EMAC_READ(sc, EMAC_STACR) & STACR_OC;
   1525 	while ((oc == STACR_OC) != sc->sc_stacr_completed) {
   1526 		delay(7);
   1527 		if (i++ > 5) {
   1528 			aprint_error_dev(sc->sc_dev, "MII timed out\n");
   1529 			return -1;
   1530 		}
   1531 		oc = EMAC_READ(sc, EMAC_STACR) & STACR_OC;
   1532 	}
   1533 	return 0;
   1534 }
   1535 
   1536 static void
   1537 emac_mii_tick(void *arg)
   1538 {
   1539 	struct emac_softc *sc = arg;
   1540 	int s;
   1541 
   1542 	if (!device_is_active(sc->sc_dev))
   1543 		return;
   1544 
   1545 	s = splnet();
   1546 	mii_tick(&sc->sc_mii);
   1547 	splx(s);
   1548 
   1549 	callout_reset(&sc->sc_callout, hz, emac_mii_tick, sc);
   1550 }
   1551 
   1552 int
   1553 emac_txeob_intr(void *arg)
   1554 {
   1555 	struct emac_softc *sc = arg;
   1556 	int handled = 0;
   1557 
   1558 	EMAC_EVCNT_INCR(&sc->sc_ev_txintr);
   1559 	handled |= emac_txreap(sc);
   1560 
   1561 	/* try to get more packets going */
   1562 	emac_start(&sc->sc_ethercom.ec_if);
   1563 
   1564 	return handled;
   1565 }
   1566 
   1567 int
   1568 emac_rxeob_intr(void *arg)
   1569 {
   1570 	struct emac_softc *sc = arg;
   1571 	struct ifnet *ifp = &sc->sc_ethercom.ec_if;
   1572 	struct emac_rxsoft *rxs;
   1573 	struct mbuf *m;
   1574 	uint32_t rxstat;
   1575 	int i, len;
   1576 
   1577 	EMAC_EVCNT_INCR(&sc->sc_ev_rxintr);
   1578 
   1579 	for (i = sc->sc_rxptr; ; i = EMAC_NEXTRX(i)) {
   1580 		rxs = &sc->sc_rxsoft[i];
   1581 
   1582 		EMAC_CDRXSYNC(sc, i,
   1583 		    BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE);
   1584 
   1585 		rxstat = sc->sc_rxdescs[i].md_stat_ctrl;
   1586 
   1587 		if (rxstat & MAL_RX_EMPTY) {
   1588 			/*
   1589 			 * We have processed all of the receive buffers.
   1590 			 */
   1591 			/* Flush current empty descriptor */
   1592 			EMAC_CDRXSYNC(sc, i,
   1593 			    BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE);
   1594 			break;
   1595 		}
   1596 
   1597 		/*
   1598 		 * If an error occurred, update stats, clear the status
   1599 		 * word, and leave the packet buffer in place.  It will
   1600 		 * simply be reused the next time the ring comes around.
   1601 		 */
   1602 		if (rxstat & (EMAC_RXS_OE | EMAC_RXS_BP | EMAC_RXS_SE |
   1603 		    EMAC_RXS_AE | EMAC_RXS_BFCS | EMAC_RXS_PTL | EMAC_RXS_ORE |
   1604 		    EMAC_RXS_IRE)) {
   1605 #define	PRINTERR(bit, str)					\
   1606 			if (rxstat & (bit))			\
   1607 				aprint_error_ifnet(ifp,		\
   1608 				    "receive error: %s\n", str)
   1609 			ifp->if_ierrors++;
   1610 			PRINTERR(EMAC_RXS_OE, "overrun error");
   1611 			PRINTERR(EMAC_RXS_BP, "bad packet");
   1612 			PRINTERR(EMAC_RXS_RP, "runt packet");
   1613 			PRINTERR(EMAC_RXS_SE, "short event");
   1614 			PRINTERR(EMAC_RXS_AE, "alignment error");
   1615 			PRINTERR(EMAC_RXS_BFCS, "bad FCS");
   1616 			PRINTERR(EMAC_RXS_PTL, "packet too long");
   1617 			PRINTERR(EMAC_RXS_ORE, "out of range error");
   1618 			PRINTERR(EMAC_RXS_IRE, "in range error");
   1619 #undef PRINTERR
   1620 			EMAC_INIT_RXDESC(sc, i);
   1621 			continue;
   1622 		}
   1623 
   1624 		bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
   1625 		    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_POSTREAD);
   1626 
   1627 		/*
   1628 		 * No errors; receive the packet.  Note, the 405GP emac
   1629 		 * includes the CRC with every packet.
   1630 		 */
   1631 		len = sc->sc_rxdescs[i].md_data_len - ETHER_CRC_LEN;
   1632 
   1633 		/*
   1634 		 * If the packet is small enough to fit in a
   1635 		 * single header mbuf, allocate one and copy
   1636 		 * the data into it.  This greatly reduces
   1637 		 * memory consumption when we receive lots
   1638 		 * of small packets.
   1639 		 *
   1640 		 * Otherwise, we add a new buffer to the receive
   1641 		 * chain.  If this fails, we drop the packet and
   1642 		 * recycle the old buffer.
   1643 		 */
   1644 		if (emac_copy_small != 0 && len <= MHLEN) {
   1645 			MGETHDR(m, M_DONTWAIT, MT_DATA);
   1646 			if (m == NULL)
   1647 				goto dropit;
   1648 			memcpy(mtod(m, void *),
   1649 			    mtod(rxs->rxs_mbuf, void *), len);
   1650 			EMAC_INIT_RXDESC(sc, i);
   1651 			bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
   1652 			    rxs->rxs_dmamap->dm_mapsize,
   1653 			    BUS_DMASYNC_PREREAD);
   1654 		} else {
   1655 			m = rxs->rxs_mbuf;
   1656 			if (emac_add_rxbuf(sc, i) != 0) {
   1657  dropit:
   1658 				ifp->if_ierrors++;
   1659 				EMAC_INIT_RXDESC(sc, i);
   1660 				bus_dmamap_sync(sc->sc_dmat,
   1661 				    rxs->rxs_dmamap, 0,
   1662 				    rxs->rxs_dmamap->dm_mapsize,
   1663 				    BUS_DMASYNC_PREREAD);
   1664 				continue;
   1665 			}
   1666 		}
   1667 
   1668 		ifp->if_ipackets++;
   1669 		m_set_rcvif(m, ifp);
   1670 		m->m_pkthdr.len = m->m_len = len;
   1671 
   1672 		/*
   1673 		 * Pass this up to any BPF listeners, but only
   1674 		 * pass it up the stack if it's for us.
   1675 		 */
   1676 		bpf_mtap(ifp, m);
   1677 
   1678 		/* Pass it on. */
   1679 		if_percpuq_enqueue(ifp->if_percpuq, m);
   1680 	}
   1681 
   1682 	/* Update the receive pointer. */
   1683 	sc->sc_rxptr = i;
   1684 
   1685 	return 1;
   1686 }
   1687 
   1688 int
   1689 emac_txde_intr(void *arg)
   1690 {
   1691 	struct emac_softc *sc = arg;
   1692 
   1693 	EMAC_EVCNT_INCR(&sc->sc_ev_txde);
   1694 	aprint_error_dev(sc->sc_dev, "emac_txde_intr\n");
   1695 	return 1;
   1696 }
   1697 
   1698 int
   1699 emac_rxde_intr(void *arg)
   1700 {
   1701 	struct emac_softc *sc = arg;
   1702 	int i;
   1703 
   1704 	EMAC_EVCNT_INCR(&sc->sc_ev_rxde);
   1705 	aprint_error_dev(sc->sc_dev, "emac_rxde_intr\n");
   1706 	/*
   1707 	 * XXX!
   1708 	 * This is a bit drastic; we just drop all descriptors that aren't
   1709 	 * "clean".  We should probably send any that are up the stack.
   1710 	 */
   1711 	for (i = 0; i < EMAC_NRXDESC; i++) {
   1712 		EMAC_CDRXSYNC(sc, i,
   1713 		    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
   1714 
   1715 		if (sc->sc_rxdescs[i].md_data_len != MCLBYTES)
   1716 			EMAC_INIT_RXDESC(sc, i);
   1717 	}
   1718 
   1719 	return 1;
   1720 }
   1721