xref: /netbsd-src/sys/arch/arm/imx/if_enet.c (revision e89934bbf778a6d6d6894877c4da59d0c7835b0f)
1 /*	$NetBSD: if_enet.c,v 1.10 2016/12/15 09:28:02 ozaki-r Exp $	*/
2 
3 /*
4  * Copyright (c) 2014 Ryo Shimizu <ryo@nerv.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
20  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
22  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
24  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
25  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 /*
30  * i.MX6,7 10/100/1000-Mbps ethernet MAC (ENET)
31  */
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: if_enet.c,v 1.10 2016/12/15 09:28:02 ozaki-r Exp $");
35 
36 #include "vlan.h"
37 
38 #include <sys/param.h>
39 #include <sys/bus.h>
40 #include <sys/mbuf.h>
41 #include <sys/device.h>
42 #include <sys/sockio.h>
43 #include <sys/kernel.h>
44 #include <sys/rndsource.h>
45 
46 #include <lib/libkern/libkern.h>
47 
48 #include <net/if.h>
49 #include <net/if_dl.h>
50 #include <net/if_media.h>
51 #include <net/if_ether.h>
52 #include <net/bpf.h>
53 #include <net/if_vlanvar.h>
54 
55 #include <netinet/in.h>
56 #include <netinet/in_systm.h>
57 #include <netinet/ip.h>
58 
59 #include <dev/mii/mii.h>
60 #include <dev/mii/miivar.h>
61 
62 #include <arm/imx/if_enetreg.h>
63 #include <arm/imx/if_enetvar.h>
64 
65 #undef DEBUG_ENET
66 #undef ENET_EVENT_COUNTER
67 
68 #define ENET_TICK	hz
69 
70 #ifdef DEBUG_ENET
71 int enet_debug = 0;
72 # define DEVICE_DPRINTF(args...)	\
73 	do { if (enet_debug) device_printf(sc->sc_dev, args); } while (0)
74 #else
75 # define DEVICE_DPRINTF(args...)
76 #endif
77 
78 
79 #define RXDESC_MAXBUFSIZE	0x07f0
80 				/* ENET does not work greather than 0x0800... */
81 
82 #undef ENET_SUPPORT_JUMBO	/* JUMBO FRAME SUPPORT is unstable */
83 #ifdef ENET_SUPPORT_JUMBO
84 # define ENET_MAX_PKT_LEN	4034	/* MAX FIFO LEN */
85 #else
86 # define ENET_MAX_PKT_LEN	1522
87 #endif
88 #define ENET_DEFAULT_PKT_LEN	1522	/* including VLAN tag */
89 #define MTU2FRAMESIZE(n)	\
90 	((n) + ETHER_HDR_LEN + ETHER_CRC_LEN + ETHER_VLAN_ENCAP_LEN)
91 
92 
93 #define ENET_MAX_PKT_NSEGS	64
94 
95 #define ENET_TX_NEXTIDX(idx)	(((idx) >= (ENET_TX_RING_CNT - 1)) ? 0 : ((idx) + 1))
96 #define ENET_RX_NEXTIDX(idx)	(((idx) >= (ENET_RX_RING_CNT - 1)) ? 0 : ((idx) + 1))
97 
98 #define TXDESC_WRITEOUT(idx)					\
99 	bus_dmamap_sync(sc->sc_dmat, sc->sc_txdesc_dmamap,	\
100 	    sizeof(struct enet_txdesc) * (idx),			\
101 	    sizeof(struct enet_txdesc),				\
102 	    BUS_DMASYNC_PREWRITE)
103 
104 #define TXDESC_READIN(idx)					\
105 	bus_dmamap_sync(sc->sc_dmat, sc->sc_txdesc_dmamap,	\
106 	    sizeof(struct enet_txdesc) * (idx),			\
107 	    sizeof(struct enet_txdesc),				\
108 	    BUS_DMASYNC_PREREAD)
109 
110 #define RXDESC_WRITEOUT(idx)					\
111 	bus_dmamap_sync(sc->sc_dmat, sc->sc_rxdesc_dmamap,	\
112 	    sizeof(struct enet_rxdesc) * (idx),			\
113 	    sizeof(struct enet_rxdesc),				\
114 	    BUS_DMASYNC_PREWRITE)
115 
116 #define RXDESC_READIN(idx)					\
117 	bus_dmamap_sync(sc->sc_dmat, sc->sc_rxdesc_dmamap,	\
118 	    sizeof(struct enet_rxdesc) * (idx),			\
119 	    sizeof(struct enet_rxdesc),				\
120 	    BUS_DMASYNC_PREREAD)
121 
122 #define ENET_REG_READ(sc, reg)					\
123 	bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, reg)
124 
125 #define ENET_REG_WRITE(sc, reg, value)				\
126 	bus_space_write_4((sc)->sc_iot, (sc)->sc_ioh, reg, value)
127 
128 #ifdef ENET_EVENT_COUNTER
129 static void enet_attach_evcnt(struct enet_softc *);
130 static void enet_update_evcnt(struct enet_softc *);
131 #endif
132 
133 static int enet_intr(void *);
134 static void enet_tick(void *);
135 static int enet_tx_intr(void *);
136 static int enet_rx_intr(void *);
137 static void enet_rx_csum(struct enet_softc *, struct ifnet *, struct mbuf *,
138                          int);
139 
140 static void enet_start(struct ifnet *);
141 static int enet_ifflags_cb(struct ethercom *);
142 static int enet_ioctl(struct ifnet *, u_long, void *);
143 static int enet_init(struct ifnet *);
144 static void enet_stop(struct ifnet *, int);
145 static void enet_watchdog(struct ifnet *);
146 static void enet_mediastatus(struct ifnet *, struct ifmediareq *);
147 
148 static int enet_miibus_readreg(device_t, int, int);
149 static void enet_miibus_writereg(device_t, int, int, int);
150 static void enet_miibus_statchg(struct ifnet *);
151 
152 static void enet_gethwaddr(struct enet_softc *, uint8_t *);
153 static void enet_sethwaddr(struct enet_softc *, uint8_t *);
154 static void enet_setmulti(struct enet_softc *);
155 static int enet_encap_mbufalign(struct mbuf **);
156 static int enet_encap_txring(struct enet_softc *, struct mbuf **);
157 static int enet_init_regs(struct enet_softc *, int);
158 static int enet_alloc_ring(struct enet_softc *);
159 static void enet_init_txring(struct enet_softc *);
160 static int enet_init_rxring(struct enet_softc *);
161 static void enet_reset_rxdesc(struct enet_softc *, int);
162 static int enet_alloc_rxbuf(struct enet_softc *, int);
163 static void enet_drain_txbuf(struct enet_softc *);
164 static void enet_drain_rxbuf(struct enet_softc *);
165 static int enet_alloc_dma(struct enet_softc *, size_t, void **,
166                           bus_dmamap_t *);
167 
168 CFATTACH_DECL_NEW(enet, sizeof(struct enet_softc),
169     enet_match, enet_attach, NULL, NULL);
170 
171 void
172 enet_attach_common(device_t self, bus_space_tag_t iot,
173     bus_dma_tag_t dmat, bus_addr_t addr, bus_size_t size, int irq)
174 {
175 	struct enet_softc *sc;
176 	struct ifnet *ifp;
177 
178 	sc = device_private(self);
179 	sc->sc_dev = self;
180 	sc->sc_iot = iot;
181 	sc->sc_addr = addr;
182 	sc->sc_dmat = dmat;
183 
184 	aprint_naive("\n");
185 	aprint_normal(": Gigabit Ethernet Controller\n");
186 	if (bus_space_map(sc->sc_iot, sc->sc_addr, size, 0,
187 	    &sc->sc_ioh)) {
188 		aprint_error_dev(self, "cannot map registers\n");
189 		return;
190 	}
191 
192 	/* allocate dma buffer */
193 	if (enet_alloc_ring(sc))
194 		return;
195 
196 #define IS_ENADDR_ZERO(enaddr)				\
197 	((enaddr[0] | enaddr[1] | enaddr[2] |		\
198 	 enaddr[3] | enaddr[4] | enaddr[5]) == 0)
199 
200 	if (IS_ENADDR_ZERO(sc->sc_enaddr)) {
201 		/* by any chance, mac-address is already set by bootloader? */
202 		enet_gethwaddr(sc, sc->sc_enaddr);
203 		if (IS_ENADDR_ZERO(sc->sc_enaddr)) {
204 			/* give up. set randomly */
205 			uint32_t eaddr = random();
206 			/* not multicast */
207 			sc->sc_enaddr[0] = (eaddr >> 24) & 0xfc;
208 			sc->sc_enaddr[1] = eaddr >> 16;
209 			sc->sc_enaddr[2] = eaddr >> 8;
210 			sc->sc_enaddr[3] = eaddr;
211 			eaddr = random();
212 			sc->sc_enaddr[4] = eaddr >> 8;
213 			sc->sc_enaddr[5] = eaddr;
214 
215 			aprint_error_dev(self,
216 			    "cannot get mac address. set randomly\n");
217 		}
218 	}
219 	enet_sethwaddr(sc, sc->sc_enaddr);
220 
221 	aprint_normal_dev(self, "Ethernet address %s\n",
222 	    ether_sprintf(sc->sc_enaddr));
223 
224 	enet_init_regs(sc, 1);
225 
226 	/* setup interrupt handlers */
227 	if ((sc->sc_ih = intr_establish(irq, IPL_NET,
228 	    IST_LEVEL, enet_intr, sc)) == NULL) {
229 		aprint_error_dev(self, "unable to establish interrupt\n");
230 		goto failure;
231 	}
232 
233 	if (sc->sc_imxtype == 7) {
234 		/* i.MX7 use 3 interrupts */
235 		if ((sc->sc_ih2 = intr_establish(irq + 1, IPL_NET,
236 		    IST_LEVEL, enet_intr, sc)) == NULL) {
237 			aprint_error_dev(self, "unable to establish 2nd interrupt\n");
238 			intr_disestablish(sc->sc_ih);
239 			goto failure;
240 		}
241 		if ((sc->sc_ih3 = intr_establish(irq + 2, IPL_NET,
242 		    IST_LEVEL, enet_intr, sc)) == NULL) {
243 			aprint_error_dev(self, "unable to establish 3rd interrupt\n");
244 			intr_disestablish(sc->sc_ih2);
245 			intr_disestablish(sc->sc_ih);
246 			goto failure;
247 		}
248 	}
249 
250 	/* callout will be scheduled from enet_init() */
251 	callout_init(&sc->sc_tick_ch, 0);
252 	callout_setfunc(&sc->sc_tick_ch, enet_tick, sc);
253 
254 	/* setup ifp */
255 	ifp = &sc->sc_ethercom.ec_if;
256 	strlcpy(ifp->if_xname, device_xname(sc->sc_dev), IFNAMSIZ);
257 	ifp->if_softc = sc;
258 	ifp->if_mtu = ETHERMTU;
259 	ifp->if_baudrate = IF_Gbps(1);
260 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
261 	ifp->if_ioctl = enet_ioctl;
262 	ifp->if_start = enet_start;
263 	ifp->if_init = enet_init;
264 	ifp->if_stop = enet_stop;
265 	ifp->if_watchdog = enet_watchdog;
266 
267 	sc->sc_ethercom.ec_capabilities |= ETHERCAP_VLAN_MTU;
268 #ifdef ENET_SUPPORT_JUMBO
269 	sc->sc_ethercom.ec_capabilities |= ETHERCAP_JUMBO_MTU;
270 #endif
271 
272 	ifp->if_capabilities = IFCAP_CSUM_IPv4_Tx | IFCAP_CSUM_IPv4_Rx |
273 	    IFCAP_CSUM_TCPv4_Tx | IFCAP_CSUM_UDPv4_Tx |
274 	    IFCAP_CSUM_TCPv4_Rx | IFCAP_CSUM_UDPv4_Rx |
275 	    IFCAP_CSUM_TCPv6_Tx | IFCAP_CSUM_UDPv6_Tx |
276 	    IFCAP_CSUM_TCPv6_Rx | IFCAP_CSUM_UDPv6_Rx;
277 
278 	IFQ_SET_MAXLEN(&ifp->if_snd, max(ENET_TX_RING_CNT, IFQ_MAXLEN));
279 	IFQ_SET_READY(&ifp->if_snd);
280 
281 	/* setup MII */
282 	sc->sc_ethercom.ec_mii = &sc->sc_mii;
283 	sc->sc_mii.mii_ifp = ifp;
284 	sc->sc_mii.mii_readreg = enet_miibus_readreg;
285 	sc->sc_mii.mii_writereg = enet_miibus_writereg;
286 	sc->sc_mii.mii_statchg = enet_miibus_statchg;
287 	ifmedia_init(&sc->sc_mii.mii_media, 0, ether_mediachange,
288 	    enet_mediastatus);
289 
290 	/* try to attach PHY */
291 	mii_attach(self, &sc->sc_mii, 0xffffffff, MII_PHY_ANY,
292 	    MII_OFFSET_ANY, 0);
293 	if (LIST_FIRST(&sc->sc_mii.mii_phys) == NULL) {
294 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER | IFM_MANUAL,
295 		    0, NULL);
296 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER | IFM_MANUAL);
297 	} else {
298 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER | IFM_AUTO);
299 	}
300 
301 	if_attach(ifp);
302 	ether_ifattach(ifp, sc->sc_enaddr);
303 	ether_set_ifflags_cb(&sc->sc_ethercom, enet_ifflags_cb);
304 
305 	rnd_attach_source(&sc->sc_rnd_source, device_xname(sc->sc_dev),
306 	    RND_TYPE_NET, RND_FLAG_DEFAULT);
307 
308 #ifdef ENET_EVENT_COUNTER
309 	enet_attach_evcnt(sc);
310 #endif
311 
312 	sc->sc_stopping = false;
313 
314 	return;
315 
316  failure:
317 	bus_space_unmap(sc->sc_iot, sc->sc_ioh, size);
318 	return;
319 }
320 
321 #ifdef ENET_EVENT_COUNTER
322 static void
323 enet_attach_evcnt(struct enet_softc *sc)
324 {
325 	const char *xname;
326 
327 	xname = device_xname(sc->sc_dev);
328 
329 #define ENET_EVCNT_ATTACH(name)	\
330 	evcnt_attach_dynamic(&sc->sc_ev_ ## name, EVCNT_TYPE_MISC,	\
331 	    NULL, xname, #name);
332 
333 	ENET_EVCNT_ATTACH(t_drop);
334 	ENET_EVCNT_ATTACH(t_packets);
335 	ENET_EVCNT_ATTACH(t_bc_pkt);
336 	ENET_EVCNT_ATTACH(t_mc_pkt);
337 	ENET_EVCNT_ATTACH(t_crc_align);
338 	ENET_EVCNT_ATTACH(t_undersize);
339 	ENET_EVCNT_ATTACH(t_oversize);
340 	ENET_EVCNT_ATTACH(t_frag);
341 	ENET_EVCNT_ATTACH(t_jab);
342 	ENET_EVCNT_ATTACH(t_col);
343 	ENET_EVCNT_ATTACH(t_p64);
344 	ENET_EVCNT_ATTACH(t_p65to127n);
345 	ENET_EVCNT_ATTACH(t_p128to255n);
346 	ENET_EVCNT_ATTACH(t_p256to511);
347 	ENET_EVCNT_ATTACH(t_p512to1023);
348 	ENET_EVCNT_ATTACH(t_p1024to2047);
349 	ENET_EVCNT_ATTACH(t_p_gte2048);
350 	ENET_EVCNT_ATTACH(t_octets);
351 	ENET_EVCNT_ATTACH(r_packets);
352 	ENET_EVCNT_ATTACH(r_bc_pkt);
353 	ENET_EVCNT_ATTACH(r_mc_pkt);
354 	ENET_EVCNT_ATTACH(r_crc_align);
355 	ENET_EVCNT_ATTACH(r_undersize);
356 	ENET_EVCNT_ATTACH(r_oversize);
357 	ENET_EVCNT_ATTACH(r_frag);
358 	ENET_EVCNT_ATTACH(r_jab);
359 	ENET_EVCNT_ATTACH(r_p64);
360 	ENET_EVCNT_ATTACH(r_p65to127);
361 	ENET_EVCNT_ATTACH(r_p128to255);
362 	ENET_EVCNT_ATTACH(r_p256to511);
363 	ENET_EVCNT_ATTACH(r_p512to1023);
364 	ENET_EVCNT_ATTACH(r_p1024to2047);
365 	ENET_EVCNT_ATTACH(r_p_gte2048);
366 	ENET_EVCNT_ATTACH(r_octets);
367 }
368 
369 static void
370 enet_update_evcnt(struct enet_softc *sc)
371 {
372 	sc->sc_ev_t_drop.ev_count += ENET_REG_READ(sc, ENET_RMON_T_DROP);
373 	sc->sc_ev_t_packets.ev_count += ENET_REG_READ(sc, ENET_RMON_T_PACKETS);
374 	sc->sc_ev_t_bc_pkt.ev_count += ENET_REG_READ(sc, ENET_RMON_T_BC_PKT);
375 	sc->sc_ev_t_mc_pkt.ev_count += ENET_REG_READ(sc, ENET_RMON_T_MC_PKT);
376 	sc->sc_ev_t_crc_align.ev_count += ENET_REG_READ(sc, ENET_RMON_T_CRC_ALIGN);
377 	sc->sc_ev_t_undersize.ev_count += ENET_REG_READ(sc, ENET_RMON_T_UNDERSIZE);
378 	sc->sc_ev_t_oversize.ev_count += ENET_REG_READ(sc, ENET_RMON_T_OVERSIZE);
379 	sc->sc_ev_t_frag.ev_count += ENET_REG_READ(sc, ENET_RMON_T_FRAG);
380 	sc->sc_ev_t_jab.ev_count += ENET_REG_READ(sc, ENET_RMON_T_JAB);
381 	sc->sc_ev_t_col.ev_count += ENET_REG_READ(sc, ENET_RMON_T_COL);
382 	sc->sc_ev_t_p64.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P64);
383 	sc->sc_ev_t_p65to127n.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P65TO127N);
384 	sc->sc_ev_t_p128to255n.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P128TO255N);
385 	sc->sc_ev_t_p256to511.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P256TO511);
386 	sc->sc_ev_t_p512to1023.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P512TO1023);
387 	sc->sc_ev_t_p1024to2047.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P1024TO2047);
388 	sc->sc_ev_t_p_gte2048.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P_GTE2048);
389 	sc->sc_ev_t_octets.ev_count += ENET_REG_READ(sc, ENET_RMON_T_OCTETS);
390 	sc->sc_ev_r_packets.ev_count += ENET_REG_READ(sc, ENET_RMON_R_PACKETS);
391 	sc->sc_ev_r_bc_pkt.ev_count += ENET_REG_READ(sc, ENET_RMON_R_BC_PKT);
392 	sc->sc_ev_r_mc_pkt.ev_count += ENET_REG_READ(sc, ENET_RMON_R_MC_PKT);
393 	sc->sc_ev_r_crc_align.ev_count += ENET_REG_READ(sc, ENET_RMON_R_CRC_ALIGN);
394 	sc->sc_ev_r_undersize.ev_count += ENET_REG_READ(sc, ENET_RMON_R_UNDERSIZE);
395 	sc->sc_ev_r_oversize.ev_count += ENET_REG_READ(sc, ENET_RMON_R_OVERSIZE);
396 	sc->sc_ev_r_frag.ev_count += ENET_REG_READ(sc, ENET_RMON_R_FRAG);
397 	sc->sc_ev_r_jab.ev_count += ENET_REG_READ(sc, ENET_RMON_R_JAB);
398 	sc->sc_ev_r_p64.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P64);
399 	sc->sc_ev_r_p65to127.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P65TO127);
400 	sc->sc_ev_r_p128to255.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P128TO255);
401 	sc->sc_ev_r_p256to511.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P256TO511);
402 	sc->sc_ev_r_p512to1023.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P512TO1023);
403 	sc->sc_ev_r_p1024to2047.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P1024TO2047);
404 	sc->sc_ev_r_p_gte2048.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P_GTE2048);
405 	sc->sc_ev_r_octets.ev_count += ENET_REG_READ(sc, ENET_RMON_R_OCTETS);
406 }
407 #endif /* ENET_EVENT_COUNTER */
408 
409 static void
410 enet_tick(void *arg)
411 {
412 	struct enet_softc *sc;
413 	struct mii_data *mii;
414 	struct ifnet *ifp;
415 	int s;
416 
417 	sc = arg;
418 	mii = &sc->sc_mii;
419 	ifp = &sc->sc_ethercom.ec_if;
420 
421 	s = splnet();
422 
423 	if (sc->sc_stopping)
424 		goto out;
425 
426 #ifdef ENET_EVENT_COUNTER
427 	enet_update_evcnt(sc);
428 #endif
429 
430 	/* update counters */
431 	ifp->if_ierrors += ENET_REG_READ(sc, ENET_RMON_R_UNDERSIZE);
432 	ifp->if_ierrors += ENET_REG_READ(sc, ENET_RMON_R_FRAG);
433 	ifp->if_ierrors += ENET_REG_READ(sc, ENET_RMON_R_JAB);
434 
435 	/* clear counters */
436 	ENET_REG_WRITE(sc, ENET_MIBC, ENET_MIBC_MIB_CLEAR);
437 	ENET_REG_WRITE(sc, ENET_MIBC, 0);
438 
439 	mii_tick(mii);
440  out:
441 
442 	if (!sc->sc_stopping)
443 		callout_schedule(&sc->sc_tick_ch, ENET_TICK);
444 
445 	splx(s);
446 }
447 
448 static int
449 enet_intr(void *arg)
450 {
451 	struct enet_softc *sc;
452 	struct ifnet *ifp;
453 	uint32_t status;
454 
455 	sc = arg;
456 	status = ENET_REG_READ(sc, ENET_EIR);
457 
458 	if (sc->sc_imxtype == 7) {
459 		if (status & (ENET_EIR_TXF|ENET_EIR_TXF1|ENET_EIR_TXF2))
460 			enet_tx_intr(arg);
461 		if (status & (ENET_EIR_RXF|ENET_EIR_RXF1|ENET_EIR_RXF2))
462 			enet_rx_intr(arg);
463 	} else {
464 		if (status & ENET_EIR_TXF)
465 			enet_tx_intr(arg);
466 		if (status & ENET_EIR_RXF)
467 			enet_rx_intr(arg);
468 	}
469 
470 	if (status & ENET_EIR_EBERR) {
471 		device_printf(sc->sc_dev, "Ethernet Bus Error\n");
472 		ifp = &sc->sc_ethercom.ec_if;
473 		enet_stop(ifp, 1);
474 		enet_init(ifp);
475 	} else {
476 		ENET_REG_WRITE(sc, ENET_EIR, status);
477 	}
478 
479 	rnd_add_uint32(&sc->sc_rnd_source, status);
480 
481 	return 1;
482 }
483 
484 static int
485 enet_tx_intr(void *arg)
486 {
487 	struct enet_softc *sc;
488 	struct ifnet *ifp;
489 	struct enet_txsoft *txs;
490 	int idx;
491 
492 	sc = (struct enet_softc *)arg;
493 	ifp = &sc->sc_ethercom.ec_if;
494 
495 	for (idx = sc->sc_tx_considx; idx != sc->sc_tx_prodidx;
496 	    idx = ENET_TX_NEXTIDX(idx)) {
497 
498 		txs = &sc->sc_txsoft[idx];
499 
500 		TXDESC_READIN(idx);
501 		if (sc->sc_txdesc_ring[idx].tx_flags1_len & TXFLAGS1_R) {
502 			/* This TX Descriptor has not been transmitted yet */
503 			break;
504 		}
505 
506 		/* txsoft is available on first segment (TXFLAGS1_T1) */
507 		if (sc->sc_txdesc_ring[idx].tx_flags1_len & TXFLAGS1_T1) {
508 			bus_dmamap_unload(sc->sc_dmat,
509 			    txs->txs_dmamap);
510 			m_freem(txs->txs_mbuf);
511 			ifp->if_opackets++;
512 		}
513 
514 		/* checking error */
515 		if (sc->sc_txdesc_ring[idx].tx_flags1_len & TXFLAGS1_L) {
516 			uint32_t flags2;
517 
518 			flags2 = sc->sc_txdesc_ring[idx].tx_flags2;
519 
520 			if (flags2 & (TXFLAGS2_TXE |
521 			    TXFLAGS2_UE | TXFLAGS2_EE | TXFLAGS2_FE |
522 			    TXFLAGS2_LCE | TXFLAGS2_OE | TXFLAGS2_TSE)) {
523 #ifdef DEBUG_ENET
524 				if (enet_debug) {
525 					char flagsbuf[128];
526 
527 					snprintb(flagsbuf, sizeof(flagsbuf),
528 					    "\20" "\20TRANSMIT" "\16UNDERFLOW"
529 					    "\15COLLISION" "\14FRAME"
530 					    "\13LATECOLLISION" "\12OVERFLOW",
531 					    flags2);
532 
533 					device_printf(sc->sc_dev,
534 					    "txdesc[%d]: transmit error: "
535 					    "flags2=%s\n", idx, flagsbuf);
536 				}
537 #endif /* DEBUG_ENET */
538 				ifp->if_oerrors++;
539 			}
540 		}
541 
542 		sc->sc_tx_free++;
543 	}
544 	sc->sc_tx_considx = idx;
545 
546 	if (sc->sc_tx_free > 0)
547 		ifp->if_flags &= ~IFF_OACTIVE;
548 
549 	/*
550 	 * No more pending TX descriptor,
551 	 * cancel the watchdog timer.
552 	 */
553 	if (sc->sc_tx_free == ENET_TX_RING_CNT)
554 		ifp->if_timer = 0;
555 
556 	return 1;
557 }
558 
559 static int
560 enet_rx_intr(void *arg)
561 {
562 	struct enet_softc *sc;
563 	struct ifnet *ifp;
564 	struct enet_rxsoft *rxs;
565 	int idx, len, amount;
566 	uint32_t flags1, flags2;
567 	struct mbuf *m, *m0, *mprev;
568 
569 	sc = arg;
570 	ifp = &sc->sc_ethercom.ec_if;
571 
572 	m0 = mprev = NULL;
573 	amount = 0;
574 	for (idx = sc->sc_rx_readidx; ; idx = ENET_RX_NEXTIDX(idx)) {
575 
576 		rxs = &sc->sc_rxsoft[idx];
577 
578 		RXDESC_READIN(idx);
579 		if (sc->sc_rxdesc_ring[idx].rx_flags1_len & RXFLAGS1_E) {
580 			/* This RX Descriptor has not been received yet */
581 			break;
582 		}
583 
584 		/*
585 		 * build mbuf from RX Descriptor if needed
586 		 */
587 		m = rxs->rxs_mbuf;
588 		rxs->rxs_mbuf = NULL;
589 
590 		flags1 = sc->sc_rxdesc_ring[idx].rx_flags1_len;
591 		len = RXFLAGS1_LEN(flags1);
592 
593 #define RACC_SHIFT16	2
594 		if (m0 == NULL) {
595 			m0 = m;
596 			m_adj(m0, RACC_SHIFT16);
597 			len -= RACC_SHIFT16;
598 			m->m_len = len;
599 			amount = len;
600 		} else {
601 			if (flags1 & RXFLAGS1_L)
602 				len = len - amount - RACC_SHIFT16;
603 
604 			m->m_len = len;
605 			amount += len;
606 			m->m_flags &= ~M_PKTHDR;
607 			mprev->m_next = m;
608 		}
609 		mprev = m;
610 
611 		flags2 = sc->sc_rxdesc_ring[idx].rx_flags2;
612 
613 		if (flags1 & RXFLAGS1_L) {
614 			/* last buffer */
615 			if ((amount < ETHER_HDR_LEN) ||
616 			    ((flags1 & (RXFLAGS1_LG | RXFLAGS1_NO |
617 			    RXFLAGS1_CR | RXFLAGS1_OV | RXFLAGS1_TR)) ||
618 			    (flags2 & (RXFLAGS2_ME | RXFLAGS2_PE |
619 			    RXFLAGS2_CE)))) {
620 
621 #ifdef DEBUG_ENET
622 				if (enet_debug) {
623 					char flags1buf[128], flags2buf[128];
624 					snprintb(flags1buf, sizeof(flags1buf),
625 					    "\20" "\31MISS" "\26LENGTHVIOLATION"
626 					    "\25NONOCTET" "\23CRC" "\22OVERRUN"
627 					    "\21TRUNCATED", flags1);
628 					snprintb(flags2buf, sizeof(flags2buf),
629 					    "\20" "\40MAC" "\33PHY"
630 					    "\32COLLISION", flags2);
631 
632 					DEVICE_DPRINTF(
633 					    "rxdesc[%d]: receive error: "
634 					    "flags1=%s,flags2=%s,len=%d\n",
635 					    idx, flags1buf, flags2buf, amount);
636 				}
637 #endif /* DEBUG_ENET */
638 				ifp->if_ierrors++;
639 				m_freem(m0);
640 
641 			} else {
642 				/* packet receive ok */
643 				m_set_rcvif(m0, ifp);
644 				m0->m_pkthdr.len = amount;
645 
646 				bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
647 				    rxs->rxs_dmamap->dm_mapsize,
648 				    BUS_DMASYNC_PREREAD);
649 
650 				if (ifp->if_csum_flags_rx & (M_CSUM_IPv4 |
651 				    M_CSUM_TCPv4 | M_CSUM_UDPv4 |
652 				    M_CSUM_TCPv6 | M_CSUM_UDPv6))
653 					enet_rx_csum(sc, ifp, m0, idx);
654 
655 				if_percpuq_enqueue(ifp->if_percpuq, m0);
656 			}
657 
658 			m0 = NULL;
659 			mprev = NULL;
660 			amount = 0;
661 
662 		} else {
663 			/* continued from previous buffer */
664 			bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
665 			    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
666 		}
667 
668 		bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
669 		if (enet_alloc_rxbuf(sc, idx) != 0) {
670 			panic("enet_alloc_rxbuf NULL\n");
671 		}
672 	}
673 	sc->sc_rx_readidx = idx;
674 
675 	/* re-enable RX DMA to make sure */
676 	ENET_REG_WRITE(sc, ENET_RDAR, ENET_RDAR_ACTIVE);
677 
678 	return 1;
679 }
680 
681 static void
682 enet_rx_csum(struct enet_softc *sc, struct ifnet *ifp, struct mbuf *m, int idx)
683 {
684 	uint32_t flags2;
685 	uint8_t proto;
686 
687 	flags2 = sc->sc_rxdesc_ring[idx].rx_flags2;
688 
689 	if (flags2 & RXFLAGS2_IPV6) {
690 		proto = sc->sc_rxdesc_ring[idx].rx_proto;
691 
692 		/* RXFLAGS2_PCR is valid when IPv6 and TCP/UDP */
693 		if ((proto == IPPROTO_TCP) &&
694 		    (ifp->if_csum_flags_rx & M_CSUM_TCPv6))
695 			m->m_pkthdr.csum_flags |= M_CSUM_TCPv6;
696 		else if ((proto == IPPROTO_UDP) &&
697 		    (ifp->if_csum_flags_rx & M_CSUM_UDPv6))
698 			m->m_pkthdr.csum_flags |= M_CSUM_UDPv6;
699 		else
700 			return;
701 
702 		/* IPv6 protocol checksum error */
703 		if (flags2 & RXFLAGS2_PCR)
704 			m->m_pkthdr.csum_flags |= M_CSUM_TCP_UDP_BAD;
705 
706 	} else {
707 		struct ether_header *eh;
708 		uint8_t *ip;
709 
710 		eh = mtod(m, struct ether_header *);
711 
712 		/* XXX: is an IPv4? */
713 		if (ntohs(eh->ether_type) != ETHERTYPE_IP)
714 			return;
715 		ip = (uint8_t *)(eh + 1);
716 		if ((ip[0] & 0xf0) == 0x40)
717 			return;
718 
719 		proto = sc->sc_rxdesc_ring[idx].rx_proto;
720 		if (flags2 & RXFLAGS2_ICE) {
721 			if (ifp->if_csum_flags_rx & M_CSUM_IPv4) {
722 				m->m_pkthdr.csum_flags |=
723 				    M_CSUM_IPv4 | M_CSUM_IPv4_BAD;
724 			}
725 		} else {
726 			if (ifp->if_csum_flags_rx & M_CSUM_IPv4) {
727 				m->m_pkthdr.csum_flags |= M_CSUM_IPv4;
728 			}
729 
730 			/*
731 			 * PCR is valid when
732 			 * ICE == 0 and FRAG == 0
733 			 */
734 			if (flags2 & RXFLAGS2_FRAG)
735 				return;
736 
737 			/*
738 			 * PCR is valid when proto is TCP or UDP
739 			 */
740 			if ((proto == IPPROTO_TCP) &&
741 			    (ifp->if_csum_flags_rx & M_CSUM_TCPv4))
742 				m->m_pkthdr.csum_flags |= M_CSUM_TCPv4;
743 			else if ((proto == IPPROTO_UDP) &&
744 			    (ifp->if_csum_flags_rx & M_CSUM_UDPv4))
745 				m->m_pkthdr.csum_flags |= M_CSUM_UDPv4;
746 			else
747 				return;
748 
749 			/* IPv4 protocol cksum error */
750 			if (flags2 & RXFLAGS2_PCR)
751 				m->m_pkthdr.csum_flags |= M_CSUM_TCP_UDP_BAD;
752 		}
753 	}
754 }
755 
756 static void
757 enet_setmulti(struct enet_softc *sc)
758 {
759 	struct ifnet *ifp;
760 	struct ether_multi *enm;
761 	struct ether_multistep step;
762 	int promisc;
763 	uint32_t crc;
764 	uint32_t gaddr[2];
765 
766 	ifp = &sc->sc_ethercom.ec_if;
767 
768 	promisc = 0;
769 	if ((ifp->if_flags & IFF_PROMISC) || sc->sc_ethercom.ec_multicnt > 0) {
770 		ifp->if_flags |= IFF_ALLMULTI;
771 		if (ifp->if_flags & IFF_PROMISC)
772 			promisc = 1;
773 		gaddr[0] = gaddr[1] = 0xffffffff;
774 	} else {
775 		gaddr[0] = gaddr[1] = 0;
776 
777 		ETHER_FIRST_MULTI(step, &sc->sc_ethercom, enm);
778 		while (enm != NULL) {
779 			crc = ether_crc32_le(enm->enm_addrlo, ETHER_ADDR_LEN);
780 			gaddr[crc >> 31] |= 1 << ((crc >> 26) & 0x1f);
781 			ETHER_NEXT_MULTI(step, enm);
782 		}
783 	}
784 
785 	ENET_REG_WRITE(sc, ENET_GAUR, gaddr[0]);
786 	ENET_REG_WRITE(sc, ENET_GALR, gaddr[1]);
787 
788 	if (promisc) {
789 		/* match all packet */
790 		ENET_REG_WRITE(sc, ENET_IAUR, 0xffffffff);
791 		ENET_REG_WRITE(sc, ENET_IALR, 0xffffffff);
792 	} else {
793 		/* don't match any packet */
794 		ENET_REG_WRITE(sc, ENET_IAUR, 0);
795 		ENET_REG_WRITE(sc, ENET_IALR, 0);
796 	}
797 }
798 
799 static void
800 enet_gethwaddr(struct enet_softc *sc, uint8_t *hwaddr)
801 {
802 	uint32_t paddr;
803 
804 	paddr = ENET_REG_READ(sc, ENET_PALR);
805 	hwaddr[0] = paddr >> 24;
806 	hwaddr[1] = paddr >> 16;
807 	hwaddr[2] = paddr >> 8;
808 	hwaddr[3] = paddr;
809 
810 	paddr = ENET_REG_READ(sc, ENET_PAUR);
811 	hwaddr[4] = paddr >> 24;
812 	hwaddr[5] = paddr >> 16;
813 }
814 
815 static void
816 enet_sethwaddr(struct enet_softc *sc, uint8_t *hwaddr)
817 {
818 	uint32_t paddr;
819 
820 	paddr = (hwaddr[0] << 24) | (hwaddr[1] << 16) | (hwaddr[2] << 8) |
821 	    hwaddr[3];
822 	ENET_REG_WRITE(sc, ENET_PALR, paddr);
823 	paddr = (hwaddr[4] << 24) | (hwaddr[5] << 16);
824 	ENET_REG_WRITE(sc, ENET_PAUR, paddr);
825 }
826 
827 /*
828  * ifnet interfaces
829  */
830 static int
831 enet_init(struct ifnet *ifp)
832 {
833 	struct enet_softc *sc;
834 	int s, error;
835 
836 	sc = ifp->if_softc;
837 
838 	s = splnet();
839 
840 	enet_init_regs(sc, 0);
841 	enet_init_txring(sc);
842 	error = enet_init_rxring(sc);
843 	if (error != 0) {
844 		enet_drain_rxbuf(sc);
845 		device_printf(sc->sc_dev, "Cannot allocate mbuf cluster\n");
846 		goto init_failure;
847 	}
848 
849 	/* reload mac address */
850 	memcpy(sc->sc_enaddr, CLLADDR(ifp->if_sadl), ETHER_ADDR_LEN);
851 	enet_sethwaddr(sc, sc->sc_enaddr);
852 
853 	/* program multicast address */
854 	enet_setmulti(sc);
855 
856 	/* update if_flags */
857 	ifp->if_flags |= IFF_RUNNING;
858 	ifp->if_flags &= ~IFF_OACTIVE;
859 
860 	/* update local copy of if_flags */
861 	sc->sc_if_flags = ifp->if_flags;
862 
863 	/* mii */
864 	mii_mediachg(&sc->sc_mii);
865 
866 	/* enable RX DMA */
867 	ENET_REG_WRITE(sc, ENET_RDAR, ENET_RDAR_ACTIVE);
868 
869 	sc->sc_stopping = false;
870 	callout_schedule(&sc->sc_tick_ch, ENET_TICK);
871 
872  init_failure:
873 	splx(s);
874 
875 	return error;
876 }
877 
878 static void
879 enet_start(struct ifnet *ifp)
880 {
881 	struct enet_softc *sc;
882 	struct mbuf *m;
883 	int npkt;
884 
885 	if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
886 		return;
887 
888 	sc = ifp->if_softc;
889 	for (npkt = 0; ; npkt++) {
890 		IFQ_POLL(&ifp->if_snd, m);
891 		if (m == NULL)
892 			break;
893 
894 		if (sc->sc_tx_free <= 0) {
895 			/* no tx descriptor now... */
896 			ifp->if_flags |= IFF_OACTIVE;
897 			DEVICE_DPRINTF("TX descriptor is full\n");
898 			break;
899 		}
900 
901 		IFQ_DEQUEUE(&ifp->if_snd, m);
902 
903 		if (enet_encap_txring(sc, &m) != 0) {
904 			/* too many mbuf chains? */
905 			ifp->if_flags |= IFF_OACTIVE;
906 			DEVICE_DPRINTF(
907 			    "TX descriptor is full. dropping packet\n");
908 			m_freem(m);
909 			ifp->if_oerrors++;
910 			break;
911 		}
912 
913 		/* Pass the packet to any BPF listeners */
914 		bpf_mtap(ifp, m);
915 	}
916 
917 	if (npkt) {
918 		/* enable TX DMA */
919 		ENET_REG_WRITE(sc, ENET_TDAR, ENET_TDAR_ACTIVE);
920 
921 		ifp->if_timer = 5;
922 	}
923 }
924 
925 static void
926 enet_stop(struct ifnet *ifp, int disable)
927 {
928 	struct enet_softc *sc;
929 	int s;
930 	uint32_t v;
931 
932 	sc = ifp->if_softc;
933 
934 	s = splnet();
935 
936 	sc->sc_stopping = true;
937 	callout_stop(&sc->sc_tick_ch);
938 
939 	/* clear ENET_ECR[ETHEREN] to abort receive and transmit */
940 	v = ENET_REG_READ(sc, ENET_ECR);
941 	ENET_REG_WRITE(sc, ENET_ECR, v & ~ENET_ECR_ETHEREN);
942 
943 	/* Mark the interface as down and cancel the watchdog timer. */
944 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
945 	ifp->if_timer = 0;
946 
947 	if (disable) {
948 		enet_drain_txbuf(sc);
949 		enet_drain_rxbuf(sc);
950 	}
951 
952 	splx(s);
953 }
954 
955 static void
956 enet_watchdog(struct ifnet *ifp)
957 {
958 	struct enet_softc *sc;
959 	int s;
960 
961 	sc = ifp->if_softc;
962 	s = splnet();
963 
964 	device_printf(sc->sc_dev, "watchdog timeout\n");
965 	ifp->if_oerrors++;
966 
967 	/* salvage packets left in descriptors */
968 	enet_tx_intr(sc);
969 	enet_rx_intr(sc);
970 
971 	/* reset */
972 	enet_stop(ifp, 1);
973 	enet_init(ifp);
974 
975 	splx(s);
976 }
977 
978 static void
979 enet_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
980 {
981 	struct enet_softc *sc = ifp->if_softc;
982 
983 	ether_mediastatus(ifp, ifmr);
984 	ifmr->ifm_active = (ifmr->ifm_active & ~IFM_ETH_FMASK)
985 	    | sc->sc_flowflags;
986 }
987 
988 static int
989 enet_ifflags_cb(struct ethercom *ec)
990 {
991 	struct ifnet *ifp = &ec->ec_if;
992 	struct enet_softc *sc = ifp->if_softc;
993 	int change = ifp->if_flags ^ sc->sc_if_flags;
994 
995 	if ((change & ~(IFF_CANTCHANGE | IFF_DEBUG)) != 0)
996 		return ENETRESET;
997 	else if ((change & (IFF_PROMISC | IFF_ALLMULTI)) == 0)
998 		return 0;
999 
1000 	enet_setmulti(sc);
1001 
1002 	sc->sc_if_flags = ifp->if_flags;
1003 	return 0;
1004 }
1005 
1006 static int
1007 enet_ioctl(struct ifnet *ifp, u_long command, void *data)
1008 {
1009 	struct enet_softc *sc;
1010 	struct ifreq *ifr;
1011 	int s, error;
1012 	uint32_t v;
1013 
1014 	sc = ifp->if_softc;
1015 	ifr = data;
1016 
1017 	error = 0;
1018 
1019 	s = splnet();
1020 
1021 	switch (command) {
1022 	case SIOCSIFMTU:
1023 		if (MTU2FRAMESIZE(ifr->ifr_mtu) > ENET_MAX_PKT_LEN) {
1024 			error = EINVAL;
1025 		} else {
1026 			ifp->if_mtu = ifr->ifr_mtu;
1027 
1028 			/* set maximum frame length */
1029 			v = MTU2FRAMESIZE(ifr->ifr_mtu);
1030 			ENET_REG_WRITE(sc, ENET_FTRL, v);
1031 			v = ENET_REG_READ(sc, ENET_RCR);
1032 			v &= ~ENET_RCR_MAX_FL(0x3fff);
1033 			v |= ENET_RCR_MAX_FL(ifp->if_mtu +
1034 			    ETHER_HDR_LEN + ETHER_CRC_LEN + ETHER_VLAN_ENCAP_LEN);
1035 			ENET_REG_WRITE(sc, ENET_RCR, v);
1036 		}
1037 		break;
1038 	case SIOCSIFMEDIA:
1039 	case SIOCGIFMEDIA:
1040 		/* Flow control requires full-duplex mode. */
1041 		if (IFM_SUBTYPE(ifr->ifr_media) == IFM_AUTO ||
1042 		    (ifr->ifr_media & IFM_FDX) == 0)
1043 			ifr->ifr_media &= ~IFM_ETH_FMASK;
1044 		if (IFM_SUBTYPE(ifr->ifr_media) != IFM_AUTO) {
1045 			if ((ifr->ifr_media & IFM_ETH_FMASK) == IFM_FLOW) {
1046 				/* We can do both TXPAUSE and RXPAUSE. */
1047 				ifr->ifr_media |=
1048 				    IFM_ETH_TXPAUSE | IFM_ETH_RXPAUSE;
1049 			}
1050 			sc->sc_flowflags = ifr->ifr_media & IFM_ETH_FMASK;
1051 		}
1052 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii.mii_media, command);
1053 		break;
1054 	default:
1055 		error = ether_ioctl(ifp, command, data);
1056 		if (error != ENETRESET)
1057 			break;
1058 
1059 		/* post-process */
1060 		error = 0;
1061 		switch (command) {
1062 		case SIOCSIFCAP:
1063 			error = (*ifp->if_init)(ifp);
1064 			break;
1065 		case SIOCADDMULTI:
1066 		case SIOCDELMULTI:
1067 			if (ifp->if_flags & IFF_RUNNING)
1068 				enet_setmulti(sc);
1069 			break;
1070 		}
1071 		break;
1072 	}
1073 
1074 	splx(s);
1075 
1076 	return error;
1077 }
1078 
1079 /*
1080  * for MII
1081  */
1082 static int
1083 enet_miibus_readreg(device_t dev, int phy, int reg)
1084 {
1085 	struct enet_softc *sc;
1086 	int timeout;
1087 	uint32_t val, status;
1088 
1089 	sc = device_private(dev);
1090 
1091 	/* clear MII update */
1092 	ENET_REG_WRITE(sc, ENET_EIR, ENET_EIR_MII);
1093 
1094 	/* read command */
1095 	ENET_REG_WRITE(sc, ENET_MMFR,
1096 	    ENET_MMFR_ST | ENET_MMFR_OP_READ | ENET_MMFR_TA |
1097 	    ENET_MMFR_PHY_REG(reg) | ENET_MMFR_PHY_ADDR(phy));
1098 
1099 	/* check MII update */
1100 	for (timeout = 5000; timeout > 0; --timeout) {
1101 		status = ENET_REG_READ(sc, ENET_EIR);
1102 		if (status & ENET_EIR_MII)
1103 			break;
1104 	}
1105 	if (timeout <= 0) {
1106 		DEVICE_DPRINTF("MII read timeout: reg=0x%02x\n",
1107 		    reg);
1108 		val = -1;
1109 	} else {
1110 		val = ENET_REG_READ(sc, ENET_MMFR) & ENET_MMFR_DATAMASK;
1111 	}
1112 
1113 	return val;
1114 }
1115 
1116 static void
1117 enet_miibus_writereg(device_t dev, int phy, int reg, int val)
1118 {
1119 	struct enet_softc *sc;
1120 	int timeout;
1121 
1122 	sc = device_private(dev);
1123 
1124 	/* clear MII update */
1125 	ENET_REG_WRITE(sc, ENET_EIR, ENET_EIR_MII);
1126 
1127 	/* write command */
1128 	ENET_REG_WRITE(sc, ENET_MMFR,
1129 	    ENET_MMFR_ST | ENET_MMFR_OP_WRITE | ENET_MMFR_TA |
1130 	    ENET_MMFR_PHY_REG(reg) | ENET_MMFR_PHY_ADDR(phy) |
1131 	    (ENET_MMFR_DATAMASK & val));
1132 
1133 	/* check MII update */
1134 	for (timeout = 5000; timeout > 0; --timeout) {
1135 		if (ENET_REG_READ(sc, ENET_EIR) & ENET_EIR_MII)
1136 			break;
1137 	}
1138 	if (timeout <= 0) {
1139 		DEVICE_DPRINTF("MII write timeout: reg=0x%02x\n",
1140 		    reg);
1141 	}
1142 }
1143 
1144 static void
1145 enet_miibus_statchg(struct ifnet *ifp)
1146 {
1147 	struct enet_softc *sc;
1148 	struct mii_data *mii;
1149 	struct ifmedia_entry *ife;
1150 	uint32_t ecr, ecr0;
1151 	uint32_t rcr, rcr0;
1152 	uint32_t tcr, tcr0;
1153 
1154 	sc = ifp->if_softc;
1155 	mii = &sc->sc_mii;
1156 	ife = mii->mii_media.ifm_cur;
1157 
1158 	/* get current status */
1159 	ecr0 = ecr = ENET_REG_READ(sc, ENET_ECR) & ~ENET_ECR_RESET;
1160 	rcr0 = rcr = ENET_REG_READ(sc, ENET_RCR);
1161 	tcr0 = tcr = ENET_REG_READ(sc, ENET_TCR);
1162 
1163 	if (IFM_SUBTYPE(mii->mii_media.ifm_cur->ifm_media) == IFM_AUTO &&
1164 	    (mii->mii_media_active & IFM_ETH_FMASK) != sc->sc_flowflags) {
1165 		sc->sc_flowflags = mii->mii_media_active & IFM_ETH_FMASK;
1166 		mii->mii_media_active &= ~IFM_ETH_FMASK;
1167 	}
1168 
1169 	if ((ife->ifm_media & IFM_GMASK) == IFM_FDX) {
1170 		tcr |= ENET_TCR_FDEN;	/* full duplex */
1171 		rcr &= ~ENET_RCR_DRT;;	/* enable receive on transmit */
1172 	} else {
1173 		tcr &= ~ENET_TCR_FDEN;	/* half duplex */
1174 		rcr |= ENET_RCR_DRT;	/* disable receive on transmit */
1175 	}
1176 
1177 	if ((tcr ^ tcr0) & ENET_TCR_FDEN) {
1178 		/*
1179 		 * need to reset because
1180 		 * FDEN can change when ECR[ETHEREN] is 0
1181 		 */
1182 		enet_init_regs(sc, 0);
1183 		return;
1184 	}
1185 
1186 	switch (IFM_SUBTYPE(ife->ifm_media)) {
1187 	case IFM_AUTO:
1188 	case IFM_1000_T:
1189 		ecr |= ENET_ECR_SPEED;		/* 1000Mbps mode */
1190 		break;
1191 	case IFM_100_TX:
1192 		ecr &= ~ENET_ECR_SPEED;		/* 100Mbps mode */
1193 		rcr &= ~ENET_RCR_RMII_10T;	/* 100Mbps mode */
1194 		break;
1195 	case IFM_10_T:
1196 		ecr &= ~ENET_ECR_SPEED;		/* 10Mbps mode */
1197 		rcr |= ENET_RCR_RMII_10T;	/* 10Mbps mode */
1198 		break;
1199 	default:
1200 		ecr = ecr0;
1201 		rcr = rcr0;
1202 		tcr = tcr0;
1203 		break;
1204 	}
1205 
1206 	if (sc->sc_flowflags & IFM_FLOW)
1207 		rcr |= ENET_RCR_FCE;
1208 	else
1209 		rcr &= ~ENET_RCR_FCE;
1210 
1211 	/* update registers if need change */
1212 	if (ecr != ecr0)
1213 		ENET_REG_WRITE(sc, ENET_ECR, ecr);
1214 	if (rcr != rcr0)
1215 		ENET_REG_WRITE(sc, ENET_RCR, rcr);
1216 	if (tcr != tcr0)
1217 		ENET_REG_WRITE(sc, ENET_TCR, tcr);
1218 }
1219 
1220 /*
1221  * handling descriptors
1222  */
1223 static void
1224 enet_init_txring(struct enet_softc *sc)
1225 {
1226 	int i;
1227 
1228 	/* build TX ring */
1229 	for (i = 0; i < ENET_TX_RING_CNT; i++) {
1230 		sc->sc_txdesc_ring[i].tx_flags1_len =
1231 		    ((i == (ENET_TX_RING_CNT - 1)) ? TXFLAGS1_W : 0);
1232 		sc->sc_txdesc_ring[i].tx_databuf = 0;
1233 		sc->sc_txdesc_ring[i].tx_flags2 = TXFLAGS2_INT;
1234 		sc->sc_txdesc_ring[i].tx__reserved1 = 0;
1235 		sc->sc_txdesc_ring[i].tx_flags3 = 0;
1236 		sc->sc_txdesc_ring[i].tx_1588timestamp = 0;
1237 		sc->sc_txdesc_ring[i].tx__reserved2 = 0;
1238 		sc->sc_txdesc_ring[i].tx__reserved3 = 0;
1239 
1240 		TXDESC_WRITEOUT(i);
1241 	}
1242 
1243 	sc->sc_tx_free = ENET_TX_RING_CNT;
1244 	sc->sc_tx_considx = 0;
1245 	sc->sc_tx_prodidx = 0;
1246 }
1247 
1248 static int
1249 enet_init_rxring(struct enet_softc *sc)
1250 {
1251 	int i, error;
1252 
1253 	/* build RX ring */
1254 	for (i = 0; i < ENET_RX_RING_CNT; i++) {
1255 		error = enet_alloc_rxbuf(sc, i);
1256 		if (error != 0)
1257 			return error;
1258 	}
1259 
1260 	sc->sc_rx_readidx = 0;
1261 
1262 	return 0;
1263 }
1264 
1265 static int
1266 enet_alloc_rxbuf(struct enet_softc *sc, int idx)
1267 {
1268 	struct mbuf *m;
1269 	int error;
1270 
1271 	KASSERT((idx >= 0) && (idx < ENET_RX_RING_CNT));
1272 
1273 	/* free mbuf if already allocated */
1274 	if (sc->sc_rxsoft[idx].rxs_mbuf != NULL) {
1275 		bus_dmamap_unload(sc->sc_dmat, sc->sc_rxsoft[idx].rxs_dmamap);
1276 		m_freem(sc->sc_rxsoft[idx].rxs_mbuf);
1277 		sc->sc_rxsoft[idx].rxs_mbuf = NULL;
1278 	}
1279 
1280 	/* allocate new mbuf cluster */
1281 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1282 	if (m == NULL)
1283 		return ENOBUFS;
1284 	MCLGET(m, M_DONTWAIT);
1285 	if (!(m->m_flags & M_EXT)) {
1286 		m_freem(m);
1287 		return ENOBUFS;
1288 	}
1289 	m->m_len = MCLBYTES;
1290 	m->m_next = NULL;
1291 
1292 	error = bus_dmamap_load(sc->sc_dmat, sc->sc_rxsoft[idx].rxs_dmamap,
1293 	    m->m_ext.ext_buf, m->m_ext.ext_size, NULL,
1294 	    BUS_DMA_READ | BUS_DMA_NOWAIT);
1295 	if (error) {
1296 		m_freem(m);
1297 		return error;
1298 	}
1299 
1300 	bus_dmamap_sync(sc->sc_dmat, sc->sc_rxsoft[idx].rxs_dmamap, 0,
1301 	    sc->sc_rxsoft[idx].rxs_dmamap->dm_mapsize,
1302 	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1303 
1304 	sc->sc_rxsoft[idx].rxs_mbuf = m;
1305 	enet_reset_rxdesc(sc, idx);
1306 	return 0;
1307 }
1308 
1309 static void
1310 enet_reset_rxdesc(struct enet_softc *sc, int idx)
1311 {
1312 	uint32_t paddr;
1313 
1314 	paddr = sc->sc_rxsoft[idx].rxs_dmamap->dm_segs[0].ds_addr;
1315 
1316 	sc->sc_rxdesc_ring[idx].rx_flags1_len =
1317 	    RXFLAGS1_E |
1318 	    ((idx == (ENET_RX_RING_CNT - 1)) ? RXFLAGS1_W : 0);
1319 	sc->sc_rxdesc_ring[idx].rx_databuf = paddr;
1320 	sc->sc_rxdesc_ring[idx].rx_flags2 =
1321 	    RXFLAGS2_INT;
1322 	sc->sc_rxdesc_ring[idx].rx_hl = 0;
1323 	sc->sc_rxdesc_ring[idx].rx_proto = 0;
1324 	sc->sc_rxdesc_ring[idx].rx_cksum = 0;
1325 	sc->sc_rxdesc_ring[idx].rx_flags3 = 0;
1326 	sc->sc_rxdesc_ring[idx].rx_1588timestamp = 0;
1327 	sc->sc_rxdesc_ring[idx].rx__reserved2 = 0;
1328 	sc->sc_rxdesc_ring[idx].rx__reserved3 = 0;
1329 
1330 	RXDESC_WRITEOUT(idx);
1331 }
1332 
1333 static void
1334 enet_drain_txbuf(struct enet_softc *sc)
1335 {
1336 	int idx;
1337 	struct enet_txsoft *txs;
1338 	struct ifnet *ifp;
1339 
1340 	ifp = &sc->sc_ethercom.ec_if;
1341 
1342 	for (idx = sc->sc_tx_considx; idx != sc->sc_tx_prodidx;
1343 	    idx = ENET_TX_NEXTIDX(idx)) {
1344 
1345 		/* txsoft[] is used only first segment */
1346 		txs = &sc->sc_txsoft[idx];
1347 		TXDESC_READIN(idx);
1348 		if (sc->sc_txdesc_ring[idx].tx_flags1_len & TXFLAGS1_T1) {
1349 			sc->sc_txdesc_ring[idx].tx_flags1_len = 0;
1350 			bus_dmamap_unload(sc->sc_dmat,
1351 			    txs->txs_dmamap);
1352 			m_freem(txs->txs_mbuf);
1353 
1354 			ifp->if_oerrors++;
1355 		}
1356 		sc->sc_tx_free++;
1357 	}
1358 }
1359 
1360 static void
1361 enet_drain_rxbuf(struct enet_softc *sc)
1362 {
1363 	int i;
1364 
1365 	for (i = 0; i < ENET_RX_RING_CNT; i++) {
1366 		if (sc->sc_rxsoft[i].rxs_mbuf != NULL) {
1367 			sc->sc_rxdesc_ring[i].rx_flags1_len = 0;
1368 			bus_dmamap_unload(sc->sc_dmat,
1369 			    sc->sc_rxsoft[i].rxs_dmamap);
1370 			m_freem(sc->sc_rxsoft[i].rxs_mbuf);
1371 			sc->sc_rxsoft[i].rxs_mbuf = NULL;
1372 		}
1373 	}
1374 }
1375 
1376 static int
1377 enet_alloc_ring(struct enet_softc *sc)
1378 {
1379 	int i, error;
1380 
1381 	/*
1382 	 * build DMA maps for TX.
1383 	 * TX descriptor must be able to contain mbuf chains,
1384 	 * so, make up ENET_MAX_PKT_NSEGS dmamap.
1385 	 */
1386 	for (i = 0; i < ENET_TX_RING_CNT; i++) {
1387 		error = bus_dmamap_create(sc->sc_dmat, ENET_MAX_PKT_LEN,
1388 		    ENET_MAX_PKT_NSEGS, ENET_MAX_PKT_LEN, 0, BUS_DMA_NOWAIT,
1389 		    &sc->sc_txsoft[i].txs_dmamap);
1390 
1391 		if (error) {
1392 			aprint_error_dev(sc->sc_dev,
1393 			    "can't create DMA map for TX descs\n");
1394 			goto fail_1;
1395 		}
1396 	}
1397 
1398 	/*
1399 	 * build DMA maps for RX.
1400 	 * RX descripter contains An mbuf cluster,
1401 	 * and make up a dmamap.
1402 	 */
1403 	for (i = 0; i < ENET_RX_RING_CNT; i++) {
1404 		error = bus_dmamap_create(sc->sc_dmat, MCLBYTES,
1405 		    1, MCLBYTES, 0, BUS_DMA_NOWAIT,
1406 		    &sc->sc_rxsoft[i].rxs_dmamap);
1407 		if (error) {
1408 			aprint_error_dev(sc->sc_dev,
1409 			    "can't create DMA map for RX descs\n");
1410 			goto fail_2;
1411 		}
1412 	}
1413 
1414 	if (enet_alloc_dma(sc, sizeof(struct enet_txdesc) * ENET_TX_RING_CNT,
1415 	    (void **)&(sc->sc_txdesc_ring), &(sc->sc_txdesc_dmamap)) != 0)
1416 		return -1;
1417 	memset(sc->sc_txdesc_ring, 0,
1418 	    sizeof(struct enet_txdesc) * ENET_TX_RING_CNT);
1419 
1420 	if (enet_alloc_dma(sc, sizeof(struct enet_rxdesc) * ENET_RX_RING_CNT,
1421 	    (void **)&(sc->sc_rxdesc_ring), &(sc->sc_rxdesc_dmamap)) != 0)
1422 		return -1;
1423 	memset(sc->sc_rxdesc_ring, 0,
1424 	    sizeof(struct enet_rxdesc) * ENET_RX_RING_CNT);
1425 
1426 	return 0;
1427 
1428  fail_2:
1429 	for (i = 0; i < ENET_RX_RING_CNT; i++) {
1430 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
1431 			bus_dmamap_destroy(sc->sc_dmat,
1432 			    sc->sc_rxsoft[i].rxs_dmamap);
1433 	}
1434  fail_1:
1435 	for (i = 0; i < ENET_TX_RING_CNT; i++) {
1436 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
1437 			bus_dmamap_destroy(sc->sc_dmat,
1438 			    sc->sc_txsoft[i].txs_dmamap);
1439 	}
1440 	return error;
1441 }
1442 
1443 static int
1444 enet_encap_mbufalign(struct mbuf **mp)
1445 {
1446 	struct mbuf *m, *m0, *mt, *p, *x;
1447 	void *ap;
1448 	uint32_t alignoff, chiplen;
1449 
1450 	/*
1451 	 * iMX6 SoC ethernet controller requires
1452 	 * address of buffer must aligned 8, and
1453 	 * length of buffer must be greater than 10 (first fragment only?)
1454 	 */
1455 #define ALIGNBYTE	8
1456 #define MINBUFSIZE	10
1457 #define ALIGN_PTR(p, align)	\
1458 	(void *)(((uintptr_t)(p) + ((align) - 1)) & -(align))
1459 
1460 	m0 = *mp;
1461 	mt = p = NULL;
1462 	for (m = m0; m != NULL; m = m->m_next) {
1463 		alignoff = (uintptr_t)m->m_data & (ALIGNBYTE - 1);
1464 		if (m->m_len < (ALIGNBYTE * 2)) {
1465 			/*
1466 			 * rearrange mbuf data aligned
1467 			 *
1468 			 *        align 8 *       *       *       *       *
1469 			 *               +0123456789abcdef0123456789abcdef0
1470 			 * FROM m->m_data[___________abcdefghijklmn_______]
1471 			 *
1472 			 *               +0123456789abcdef0123456789abcdef0
1473 			 * TO   m->m_data[________abcdefghijklm___________] or
1474 			 *      m->m_data[________________abcdefghijklmn__]
1475 			 */
1476 			if ((alignoff != 0) && (m->m_len != 0)) {
1477 				chiplen = ALIGNBYTE - alignoff;
1478 				if (M_LEADINGSPACE(m) >= alignoff) {
1479 					ap = m->m_data - alignoff;
1480 					memmove(ap, m->m_data, m->m_len);
1481 					m->m_data = ap;
1482 				} else if (M_TRAILINGSPACE(m) >= chiplen) {
1483 					ap = m->m_data + chiplen;
1484 					memmove(ap, m->m_data, m->m_len);
1485 					m->m_data = ap;
1486 				} else {
1487 					/*
1488 					 * no space to align data. (M_READONLY?)
1489 					 * allocate new mbuf aligned,
1490 					 * and copy to it.
1491 					 */
1492 					MGET(x, M_DONTWAIT, m->m_type);
1493 					if (x == NULL) {
1494 						m_freem(m);
1495 						return ENOBUFS;
1496 					}
1497 					MCLAIM(x, m->m_owner);
1498 					if (m->m_flags & M_PKTHDR)
1499 						M_MOVE_PKTHDR(x, m);
1500 					x->m_len = m->m_len;
1501 					x->m_data = ALIGN_PTR(x->m_data,
1502 					    ALIGNBYTE);
1503 					memcpy(mtod(x, void *), mtod(m, void *),
1504 					    m->m_len);
1505 					p->m_next = x;
1506 					x->m_next = m_free(m);
1507 					m = x;
1508 				}
1509 			}
1510 
1511 			/*
1512 			 * fill 1st mbuf at least 10byte
1513 			 *
1514 			 *        align 8 *       *       *       *       *
1515 			 *               +0123456789abcdef0123456789abcdef0
1516 			 * FROM m->m_data[________abcde___________________]
1517 			 *      m->m_data[__fg____________________________]
1518 			 *      m->m_data[_________________hi_____________]
1519 			 *      m->m_data[__________jk____________________]
1520 			 *      m->m_data[____l___________________________]
1521 			 *
1522 			 *               +0123456789abcdef0123456789abcdef0
1523 			 * TO   m->m_data[________abcdefghij______________]
1524 			 *      m->m_data[________________________________]
1525 			 *      m->m_data[________________________________]
1526 			 *      m->m_data[___________k____________________]
1527 			 *      m->m_data[____l___________________________]
1528 			 */
1529 			if (mt == NULL) {
1530 				mt = m;
1531 				while (mt->m_len == 0) {
1532 					mt = mt->m_next;
1533 					if (mt == NULL) {
1534 						m_freem(m);
1535 						return ENOBUFS;
1536 					}
1537 				}
1538 
1539 				/* mt = 1st mbuf, x = 2nd mbuf */
1540 				x = mt->m_next;
1541 				while (mt->m_len < MINBUFSIZE) {
1542 					if (x == NULL) {
1543 						m_freem(m);
1544 						return ENOBUFS;
1545 					}
1546 
1547 					alignoff = (uintptr_t)x->m_data &
1548 					    (ALIGNBYTE - 1);
1549 					chiplen = ALIGNBYTE - alignoff;
1550 					if (chiplen > x->m_len) {
1551 						chiplen = x->m_len;
1552 					} else if ((mt->m_len + chiplen) <
1553 					    MINBUFSIZE) {
1554 						/*
1555 						 * next mbuf should be greater
1556 						 * than ALIGNBYTE?
1557 						 */
1558 						if (x->m_len >= (chiplen +
1559 						    ALIGNBYTE * 2))
1560 							chiplen += ALIGNBYTE;
1561 						else
1562 							chiplen = x->m_len;
1563 					}
1564 
1565 					if (chiplen &&
1566 					    (M_TRAILINGSPACE(mt) < chiplen)) {
1567 						/*
1568 						 * move data to the begining of
1569 						 * m_dat[] (aligned) to en-
1570 						 * large trailingspace
1571 						 */
1572 						if (mt->m_flags & M_EXT) {
1573 							ap = mt->m_ext.ext_buf;
1574 						} else if (mt->m_flags &
1575 						    M_PKTHDR) {
1576 							ap = mt->m_pktdat;
1577 						} else {
1578 							ap = mt->m_dat;
1579 						}
1580 						ap = ALIGN_PTR(ap, ALIGNBYTE);
1581 						memcpy(ap, mt->m_data, mt->m_len);
1582 						mt->m_data = ap;
1583 					}
1584 
1585 					if (chiplen &&
1586 					    (M_TRAILINGSPACE(mt) >= chiplen)) {
1587 						memcpy(mt->m_data + mt->m_len,
1588 						    x->m_data, chiplen);
1589 						mt->m_len += chiplen;
1590 						m_adj(x, chiplen);
1591 					}
1592 
1593 					x = x->m_next;
1594 				}
1595 			}
1596 
1597 		} else {
1598 			mt = m;
1599 
1600 			/*
1601 			 * allocate new mbuf x, and rearrange as below;
1602 			 *
1603 			 *        align 8 *       *       *       *       *
1604 			 *               +0123456789abcdef0123456789abcdef0
1605 			 * FROM m->m_data[____________abcdefghijklmnopq___]
1606 			 *
1607 			 *               +0123456789abcdef0123456789abcdef0
1608 			 * TO   x->m_data[________abcdefghijkl____________]
1609 			 *      m->m_data[________________________mnopq___]
1610 			 *
1611 			 */
1612 			if (alignoff != 0) {
1613 				/* at least ALIGNBYTE */
1614 				chiplen = ALIGNBYTE - alignoff + ALIGNBYTE;
1615 
1616 				MGET(x, M_DONTWAIT, m->m_type);
1617 				if (x == NULL) {
1618 					m_freem(m);
1619 					return ENOBUFS;
1620 				}
1621 				MCLAIM(x, m->m_owner);
1622 				if (m->m_flags & M_PKTHDR)
1623 					M_MOVE_PKTHDR(x, m);
1624 				x->m_data = ALIGN_PTR(x->m_data, ALIGNBYTE);
1625 				memcpy(mtod(x, void *), mtod(m, void *),
1626 				    chiplen);
1627 				x->m_len = chiplen;
1628 				x->m_next = m;
1629 				m_adj(m, chiplen);
1630 
1631 				if (p == NULL)
1632 					m0 = x;
1633 				else
1634 					p->m_next = x;
1635 			}
1636 		}
1637 		p = m;
1638 	}
1639 	*mp = m0;
1640 
1641 	return 0;
1642 }
1643 
1644 static int
1645 enet_encap_txring(struct enet_softc *sc, struct mbuf **mp)
1646 {
1647 	bus_dmamap_t map;
1648 	struct mbuf *m;
1649 	int csumflags, idx, i, error;
1650 	uint32_t flags1, flags2;
1651 
1652 	idx = sc->sc_tx_prodidx;
1653 	map = sc->sc_txsoft[idx].txs_dmamap;
1654 
1655 	/* align mbuf data for claim of ENET */
1656 	error = enet_encap_mbufalign(mp);
1657 	if (error != 0)
1658 		return error;
1659 
1660 	m = *mp;
1661 	csumflags = m->m_pkthdr.csum_flags;
1662 
1663 	error = bus_dmamap_load_mbuf(sc->sc_dmat, map, m,
1664 	    BUS_DMA_NOWAIT);
1665 	if (error != 0) {
1666 		device_printf(sc->sc_dev,
1667 		    "Error mapping mbuf into TX chain: error=%d\n", error);
1668 		m_freem(m);
1669 		return error;
1670 	}
1671 
1672 	if (map->dm_nsegs > sc->sc_tx_free) {
1673 		bus_dmamap_unload(sc->sc_dmat, map);
1674 		device_printf(sc->sc_dev,
1675 		    "too many mbuf chain %d\n", map->dm_nsegs);
1676 		m_freem(m);
1677 		return ENOBUFS;
1678 	}
1679 
1680 	/* fill protocol cksum zero beforehand */
1681 	if (csumflags & (M_CSUM_UDPv4 | M_CSUM_TCPv4 |
1682 	    M_CSUM_UDPv6 | M_CSUM_TCPv6)) {
1683 		struct mbuf *m1;
1684 		int ehlen, moff;
1685 		uint16_t etype;
1686 
1687 		m_copydata(m, ETHER_ADDR_LEN * 2, sizeof(etype), &etype);
1688 		switch (ntohs(etype)) {
1689 		case ETHERTYPE_IP:
1690 		case ETHERTYPE_IPV6:
1691 			ehlen = ETHER_HDR_LEN;
1692 			break;
1693 		case ETHERTYPE_VLAN:
1694 			ehlen = ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN;
1695 			break;
1696 		default:
1697 			ehlen = 0;
1698 			break;
1699 		}
1700 
1701 		if (ehlen) {
1702 			m1 = m_getptr(m, ehlen +
1703 			    M_CSUM_DATA_IPv4_IPHL(m->m_pkthdr.csum_data) +
1704 			    M_CSUM_DATA_IPv4_OFFSET(m->m_pkthdr.csum_data),
1705 			    &moff);
1706 			if (m1 != NULL)
1707 				*(uint16_t *)(mtod(m1, char *) + moff) = 0;
1708 		}
1709 	}
1710 
1711 	bus_dmamap_sync(sc->sc_dmat, map, 0, map->dm_mapsize,
1712 	    BUS_DMASYNC_PREWRITE);
1713 
1714 	for (i = 0; i < map->dm_nsegs; i++) {
1715 		flags1 = TXFLAGS1_R;
1716 		flags2 = 0;
1717 
1718 		if (i == 0) {
1719 			flags1 |= TXFLAGS1_T1;	/* mark as first segment */
1720 			sc->sc_txsoft[idx].txs_mbuf = m;
1721 		}
1722 
1723 		/* checksum offloading */
1724 		if (csumflags & (M_CSUM_UDPv4 | M_CSUM_TCPv4 |
1725 		    M_CSUM_UDPv6 | M_CSUM_TCPv6))
1726 			flags2 |= TXFLAGS2_PINS;
1727 		if (csumflags & (M_CSUM_IPv4))
1728 			flags2 |= TXFLAGS2_IINS;
1729 
1730 		if (i == map->dm_nsegs - 1) {
1731 			/* mark last segment */
1732 			flags1 |= TXFLAGS1_L | TXFLAGS1_TC;
1733 			flags2 |= TXFLAGS2_INT;
1734 		}
1735 		if (idx == ENET_TX_RING_CNT - 1) {
1736 			/* mark end of ring */
1737 			flags1 |= TXFLAGS1_W;
1738 		}
1739 
1740 		sc->sc_txdesc_ring[idx].tx_databuf = map->dm_segs[i].ds_addr;
1741 		sc->sc_txdesc_ring[idx].tx_flags2 = flags2;
1742 		sc->sc_txdesc_ring[idx].tx_flags3 = 0;
1743 		TXDESC_WRITEOUT(idx);
1744 
1745 		sc->sc_txdesc_ring[idx].tx_flags1_len =
1746 		    flags1 | TXFLAGS1_LEN(map->dm_segs[i].ds_len);
1747 		TXDESC_WRITEOUT(idx);
1748 
1749 		idx = ENET_TX_NEXTIDX(idx);
1750 		sc->sc_tx_free--;
1751 	}
1752 
1753 	sc->sc_tx_prodidx = idx;
1754 
1755 	return 0;
1756 }
1757 
1758 /*
1759  * device initialize
1760  */
1761 static int
1762 enet_init_regs(struct enet_softc *sc, int init)
1763 {
1764 	struct mii_data *mii;
1765 	struct ifmedia_entry *ife;
1766 	paddr_t paddr;
1767 	uint32_t val;
1768 	int fulldup, ecr_speed, rcr_speed, flowctrl;
1769 
1770 	if (init) {
1771 		fulldup = 1;
1772 		ecr_speed = ENET_ECR_SPEED;
1773 		rcr_speed = 0;
1774 		flowctrl = 0;
1775 	} else {
1776 		mii = &sc->sc_mii;
1777 		ife = mii->mii_media.ifm_cur;
1778 
1779 		if ((ife->ifm_media & IFM_GMASK) == IFM_FDX)
1780 			fulldup = 1;
1781 		else
1782 			fulldup = 0;
1783 
1784 		switch (IFM_SUBTYPE(ife->ifm_media)) {
1785 		case IFM_10_T:
1786 			ecr_speed = 0;
1787 			rcr_speed = ENET_RCR_RMII_10T;
1788 			break;
1789 		case IFM_100_TX:
1790 			ecr_speed = 0;
1791 			rcr_speed = 0;
1792 			break;
1793 		default:
1794 			ecr_speed = ENET_ECR_SPEED;
1795 			rcr_speed = 0;
1796 			break;
1797 		}
1798 
1799 		flowctrl = sc->sc_flowflags & IFM_FLOW;
1800 	}
1801 
1802 	/* reset */
1803 	ENET_REG_WRITE(sc, ENET_ECR, ecr_speed | ENET_ECR_RESET);
1804 
1805 	/* mask and clear all interrupt */
1806 	ENET_REG_WRITE(sc, ENET_EIMR, 0);
1807 	ENET_REG_WRITE(sc, ENET_EIR, 0xffffffff);
1808 
1809 	/* full duplex */
1810 	ENET_REG_WRITE(sc, ENET_TCR, fulldup ? ENET_TCR_FDEN : 0);
1811 
1812 	/* clear and enable MIB register */
1813 	ENET_REG_WRITE(sc, ENET_MIBC, ENET_MIBC_MIB_CLEAR);
1814 	ENET_REG_WRITE(sc, ENET_MIBC, 0);
1815 
1816 	/* MII speed setup. MDCclk(=2.5MHz) = ENET_PLL/((val+1)*2) */
1817 	val = ((sc->sc_pllclock) / 500000 - 1) / 10;
1818 	ENET_REG_WRITE(sc, ENET_MSCR, val << 1);
1819 
1820 	/* Opcode/Pause Duration */
1821 	ENET_REG_WRITE(sc, ENET_OPD, 0x00010020);
1822 
1823 	/* Receive FIFO */
1824 	ENET_REG_WRITE(sc, ENET_RSFL, 16);	/* RxFIFO Section Full */
1825 	ENET_REG_WRITE(sc, ENET_RSEM, 0x84);	/* RxFIFO Section Empty */
1826 	ENET_REG_WRITE(sc, ENET_RAEM, 8);	/* RxFIFO Almost Empty */
1827 	ENET_REG_WRITE(sc, ENET_RAFL, 8);	/* RxFIFO Almost Full */
1828 
1829 	/* Transmit FIFO */
1830 	ENET_REG_WRITE(sc, ENET_TFWR, ENET_TFWR_STRFWD |
1831 	    ENET_TFWR_FIFO(128));		/* TxFIFO Watermark */
1832 	ENET_REG_WRITE(sc, ENET_TSEM, 0);	/* TxFIFO Section Empty */
1833 	ENET_REG_WRITE(sc, ENET_TAEM, 256);	/* TxFIFO Almost Empty */
1834 	ENET_REG_WRITE(sc, ENET_TAFL, 8);	/* TxFIFO Almost Full */
1835 	ENET_REG_WRITE(sc, ENET_TIPG, 12);	/* Tx Inter-Packet Gap */
1836 
1837 	/* hardware checksum is default off (override in TX descripter) */
1838 	ENET_REG_WRITE(sc, ENET_TACC, 0);
1839 
1840 	/*
1841 	 * align ethernet payload on 32bit, discard frames with MAC layer error,
1842 	 * and don't discard checksum error
1843 	 */
1844 	ENET_REG_WRITE(sc, ENET_RACC, ENET_RACC_SHIFT16 | ENET_RACC_LINEDIS);
1845 
1846 	/* maximum frame size */
1847 	val = ENET_DEFAULT_PKT_LEN;
1848 	ENET_REG_WRITE(sc, ENET_FTRL, val);	/* Frame Truncation Length */
1849 	ENET_REG_WRITE(sc, ENET_RCR,
1850 	    ENET_RCR_PADEN |			/* RX frame padding remove */
1851 	    ENET_RCR_RGMII_EN |			/* use RGMII */
1852 	    (flowctrl ? ENET_RCR_FCE : 0) |	/* flow control enable */
1853 	    rcr_speed |
1854 	    (fulldup ? 0 : ENET_RCR_DRT) |
1855 	    ENET_RCR_MAX_FL(val));
1856 
1857 	/* Maximum Receive BufSize per one descriptor */
1858 	ENET_REG_WRITE(sc, ENET_MRBR, RXDESC_MAXBUFSIZE);
1859 
1860 
1861 	/* TX/RX Descriptor Physical Address */
1862 	paddr = sc->sc_txdesc_dmamap->dm_segs[0].ds_addr;
1863 	ENET_REG_WRITE(sc, ENET_TDSR, paddr);
1864 	paddr = sc->sc_rxdesc_dmamap->dm_segs[0].ds_addr;
1865 	ENET_REG_WRITE(sc, ENET_RDSR, paddr);
1866 	/* sync cache */
1867 	bus_dmamap_sync(sc->sc_dmat, sc->sc_txdesc_dmamap, 0,
1868 	    sc->sc_txdesc_dmamap->dm_mapsize, BUS_DMASYNC_PREWRITE);
1869 	bus_dmamap_sync(sc->sc_dmat, sc->sc_rxdesc_dmamap, 0,
1870 	    sc->sc_rxdesc_dmamap->dm_mapsize, BUS_DMASYNC_PREWRITE);
1871 
1872 	/* enable interrupts */
1873 	val = ENET_EIMR|ENET_EIR_TXF|ENET_EIR_RXF|ENET_EIR_EBERR;
1874 	if (sc->sc_imxtype == 7)
1875 		val |= ENET_EIR_TXF2|ENET_EIR_RXF2|ENET_EIR_TXF1|ENET_EIR_RXF1;
1876 	ENET_REG_WRITE(sc, ENET_EIMR, val);
1877 
1878 	/* enable ether */
1879 	ENET_REG_WRITE(sc, ENET_ECR,
1880 #if _BYTE_ORDER == _LITTLE_ENDIAN
1881 	    ENET_ECR_DBSWP |
1882 #endif
1883 	    ENET_ECR_SPEED |	/* default 1000Mbps mode */
1884 	    ENET_ECR_EN1588 |	/* use enhanced TX/RX descriptor */
1885 	    ENET_ECR_ETHEREN);	/* Ethernet Enable */
1886 
1887 	return 0;
1888 }
1889 
1890 static int
1891 enet_alloc_dma(struct enet_softc *sc, size_t size, void **addrp,
1892               bus_dmamap_t *mapp)
1893 {
1894 	bus_dma_segment_t seglist[1];
1895 	int nsegs, error;
1896 
1897 	if ((error = bus_dmamem_alloc(sc->sc_dmat, size, PAGE_SIZE, 0, seglist,
1898 	    1, &nsegs, M_NOWAIT)) != 0) {
1899 		device_printf(sc->sc_dev,
1900 		    "unable to allocate DMA buffer, error=%d\n", error);
1901 		goto fail_alloc;
1902 	}
1903 
1904 	if ((error = bus_dmamem_map(sc->sc_dmat, seglist, 1, size, addrp,
1905 	    BUS_DMA_NOWAIT | BUS_DMA_COHERENT)) != 0) {
1906 		device_printf(sc->sc_dev,
1907 		    "unable to map DMA buffer, error=%d\n",
1908 		    error);
1909 		goto fail_map;
1910 	}
1911 
1912 	if ((error = bus_dmamap_create(sc->sc_dmat, size, 1, size, 0,
1913 	    BUS_DMA_NOWAIT, mapp)) != 0) {
1914 		device_printf(sc->sc_dev,
1915 		    "unable to create DMA map, error=%d\n", error);
1916 		goto fail_create;
1917 	}
1918 
1919 	if ((error = bus_dmamap_load(sc->sc_dmat, *mapp, *addrp, size, NULL,
1920 	    BUS_DMA_NOWAIT)) != 0) {
1921 		aprint_error_dev(sc->sc_dev,
1922 		    "unable to load DMA map, error=%d\n", error);
1923 		goto fail_load;
1924 	}
1925 
1926 	return 0;
1927 
1928  fail_load:
1929 	bus_dmamap_destroy(sc->sc_dmat, *mapp);
1930  fail_create:
1931 	bus_dmamem_unmap(sc->sc_dmat, *addrp, size);
1932  fail_map:
1933 	bus_dmamem_free(sc->sc_dmat, seglist, 1);
1934  fail_alloc:
1935 	return error;
1936 }
1937