xref: /netbsd-src/sys/arch/arm/imx/if_enet.c (revision c9496f6b604074a9451a67df576a5b423068e71e)
1 /*	$NetBSD: if_enet.c,v 1.11 2017/06/09 18:14:59 ryo 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 1.11 2017/06/09 18:14:59 ryo 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)	\
96 	(((idx) >= (ENET_TX_RING_CNT - 1)) ? 0 : ((idx) + 1))
97 #define ENET_RX_NEXTIDX(idx)	\
98 	(((idx) >= (ENET_RX_RING_CNT - 1)) ? 0 : ((idx) + 1))
99 
100 #define TXDESC_WRITEOUT(idx)					\
101 	bus_dmamap_sync(sc->sc_dmat, sc->sc_txdesc_dmamap,	\
102 	    sizeof(struct enet_txdesc) * (idx),			\
103 	    sizeof(struct enet_txdesc),				\
104 	    BUS_DMASYNC_PREWRITE)
105 
106 #define TXDESC_READIN(idx)					\
107 	bus_dmamap_sync(sc->sc_dmat, sc->sc_txdesc_dmamap,	\
108 	    sizeof(struct enet_txdesc) * (idx),			\
109 	    sizeof(struct enet_txdesc),				\
110 	    BUS_DMASYNC_PREREAD)
111 
112 #define RXDESC_WRITEOUT(idx)					\
113 	bus_dmamap_sync(sc->sc_dmat, sc->sc_rxdesc_dmamap,	\
114 	    sizeof(struct enet_rxdesc) * (idx),			\
115 	    sizeof(struct enet_rxdesc),				\
116 	    BUS_DMASYNC_PREWRITE)
117 
118 #define RXDESC_READIN(idx)					\
119 	bus_dmamap_sync(sc->sc_dmat, sc->sc_rxdesc_dmamap,	\
120 	    sizeof(struct enet_rxdesc) * (idx),			\
121 	    sizeof(struct enet_rxdesc),				\
122 	    BUS_DMASYNC_PREREAD)
123 
124 #define ENET_REG_READ(sc, reg)					\
125 	bus_space_read_4((sc)->sc_iot, (sc)->sc_ioh, reg)
126 
127 #define ENET_REG_WRITE(sc, reg, value)				\
128 	bus_space_write_4((sc)->sc_iot, (sc)->sc_ioh, reg, value)
129 
130 #ifdef ENET_EVENT_COUNTER
131 static void enet_attach_evcnt(struct enet_softc *);
132 static void enet_update_evcnt(struct enet_softc *);
133 #endif
134 
135 static int enet_intr(void *);
136 static void enet_tick(void *);
137 static int enet_tx_intr(void *);
138 static int enet_rx_intr(void *);
139 static void enet_rx_csum(struct enet_softc *, struct ifnet *, struct mbuf *,
140                          int);
141 
142 static void enet_start(struct ifnet *);
143 static int enet_ifflags_cb(struct ethercom *);
144 static int enet_ioctl(struct ifnet *, u_long, void *);
145 static int enet_init(struct ifnet *);
146 static void enet_stop(struct ifnet *, int);
147 static void enet_watchdog(struct ifnet *);
148 static void enet_mediastatus(struct ifnet *, struct ifmediareq *);
149 
150 static int enet_miibus_readreg(device_t, int, int);
151 static void enet_miibus_writereg(device_t, int, int, int);
152 static void enet_miibus_statchg(struct ifnet *);
153 
154 static void enet_gethwaddr(struct enet_softc *, uint8_t *);
155 static void enet_sethwaddr(struct enet_softc *, uint8_t *);
156 static void enet_setmulti(struct enet_softc *);
157 static int enet_encap_mbufalign(struct mbuf **);
158 static int enet_encap_txring(struct enet_softc *, struct mbuf **);
159 static int enet_init_regs(struct enet_softc *, int);
160 static int enet_alloc_ring(struct enet_softc *);
161 static void enet_init_txring(struct enet_softc *);
162 static int enet_init_rxring(struct enet_softc *);
163 static void enet_reset_rxdesc(struct enet_softc *, int);
164 static int enet_alloc_rxbuf(struct enet_softc *, int);
165 static void enet_drain_txbuf(struct enet_softc *);
166 static void enet_drain_rxbuf(struct enet_softc *);
167 static int enet_alloc_dma(struct enet_softc *, size_t, void **,
168                           bus_dmamap_t *);
169 
170 CFATTACH_DECL_NEW(enet, sizeof(struct enet_softc),
171     enet_match, enet_attach, NULL, NULL);
172 
173 void
174 enet_attach_common(device_t self, bus_space_tag_t iot,
175     bus_dma_tag_t dmat, bus_addr_t addr, bus_size_t size, int irq)
176 {
177 	struct enet_softc *sc;
178 	struct ifnet *ifp;
179 
180 	sc = device_private(self);
181 	sc->sc_dev = self;
182 	sc->sc_iot = iot;
183 	sc->sc_addr = addr;
184 	sc->sc_dmat = dmat;
185 
186 	aprint_naive("\n");
187 	aprint_normal(": Gigabit Ethernet Controller\n");
188 	if (bus_space_map(sc->sc_iot, sc->sc_addr, size, 0,
189 	    &sc->sc_ioh)) {
190 		aprint_error_dev(self, "cannot map registers\n");
191 		return;
192 	}
193 
194 	/* allocate dma buffer */
195 	if (enet_alloc_ring(sc))
196 		return;
197 
198 #define IS_ENADDR_ZERO(enaddr)				\
199 	((enaddr[0] | enaddr[1] | enaddr[2] |		\
200 	 enaddr[3] | enaddr[4] | enaddr[5]) == 0)
201 
202 	if (IS_ENADDR_ZERO(sc->sc_enaddr)) {
203 		/* by any chance, mac-address is already set by bootloader? */
204 		enet_gethwaddr(sc, sc->sc_enaddr);
205 		if (IS_ENADDR_ZERO(sc->sc_enaddr)) {
206 			/* give up. set randomly */
207 			uint32_t eaddr = random();
208 			/* not multicast */
209 			sc->sc_enaddr[0] = (eaddr >> 24) & 0xfc;
210 			sc->sc_enaddr[1] = eaddr >> 16;
211 			sc->sc_enaddr[2] = eaddr >> 8;
212 			sc->sc_enaddr[3] = eaddr;
213 			eaddr = random();
214 			sc->sc_enaddr[4] = eaddr >> 8;
215 			sc->sc_enaddr[5] = eaddr;
216 
217 			aprint_error_dev(self,
218 			    "cannot get mac address. set randomly\n");
219 		}
220 	}
221 	enet_sethwaddr(sc, sc->sc_enaddr);
222 
223 	aprint_normal_dev(self, "Ethernet address %s\n",
224 	    ether_sprintf(sc->sc_enaddr));
225 
226 	enet_init_regs(sc, 1);
227 
228 	/* setup interrupt handlers */
229 	if ((sc->sc_ih = intr_establish(irq, IPL_NET,
230 	    IST_LEVEL, enet_intr, sc)) == NULL) {
231 		aprint_error_dev(self, "unable to establish interrupt\n");
232 		goto failure;
233 	}
234 
235 	if (sc->sc_imxtype == 7) {
236 		/* i.MX7 use 3 interrupts */
237 		if ((sc->sc_ih2 = intr_establish(irq + 1, IPL_NET,
238 		    IST_LEVEL, enet_intr, sc)) == NULL) {
239 			aprint_error_dev(self,
240 			    "unable to establish 2nd interrupt\n");
241 			intr_disestablish(sc->sc_ih);
242 			goto failure;
243 		}
244 		if ((sc->sc_ih3 = intr_establish(irq + 2, IPL_NET,
245 		    IST_LEVEL, enet_intr, sc)) == NULL) {
246 			aprint_error_dev(self,
247 			    "unable to establish 3rd interrupt\n");
248 			intr_disestablish(sc->sc_ih2);
249 			intr_disestablish(sc->sc_ih);
250 			goto failure;
251 		}
252 	}
253 
254 	/* callout will be scheduled from enet_init() */
255 	callout_init(&sc->sc_tick_ch, 0);
256 	callout_setfunc(&sc->sc_tick_ch, enet_tick, sc);
257 
258 	/* setup ifp */
259 	ifp = &sc->sc_ethercom.ec_if;
260 	strlcpy(ifp->if_xname, device_xname(sc->sc_dev), IFNAMSIZ);
261 	ifp->if_softc = sc;
262 	ifp->if_mtu = ETHERMTU;
263 	ifp->if_baudrate = IF_Gbps(1);
264 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
265 	ifp->if_ioctl = enet_ioctl;
266 	ifp->if_start = enet_start;
267 	ifp->if_init = enet_init;
268 	ifp->if_stop = enet_stop;
269 	ifp->if_watchdog = enet_watchdog;
270 
271 	sc->sc_ethercom.ec_capabilities |= ETHERCAP_VLAN_MTU;
272 #ifdef ENET_SUPPORT_JUMBO
273 	sc->sc_ethercom.ec_capabilities |= ETHERCAP_JUMBO_MTU;
274 #endif
275 
276 	ifp->if_capabilities = IFCAP_CSUM_IPv4_Tx | IFCAP_CSUM_IPv4_Rx |
277 	    IFCAP_CSUM_TCPv4_Tx | IFCAP_CSUM_UDPv4_Tx |
278 	    IFCAP_CSUM_TCPv4_Rx | IFCAP_CSUM_UDPv4_Rx |
279 	    IFCAP_CSUM_TCPv6_Tx | IFCAP_CSUM_UDPv6_Tx |
280 	    IFCAP_CSUM_TCPv6_Rx | IFCAP_CSUM_UDPv6_Rx;
281 
282 	IFQ_SET_MAXLEN(&ifp->if_snd, max(ENET_TX_RING_CNT, IFQ_MAXLEN));
283 	IFQ_SET_READY(&ifp->if_snd);
284 
285 	/* setup MII */
286 	sc->sc_ethercom.ec_mii = &sc->sc_mii;
287 	sc->sc_mii.mii_ifp = ifp;
288 	sc->sc_mii.mii_readreg = enet_miibus_readreg;
289 	sc->sc_mii.mii_writereg = enet_miibus_writereg;
290 	sc->sc_mii.mii_statchg = enet_miibus_statchg;
291 	ifmedia_init(&sc->sc_mii.mii_media, 0, ether_mediachange,
292 	    enet_mediastatus);
293 
294 	/* try to attach PHY */
295 	mii_attach(self, &sc->sc_mii, 0xffffffff, MII_PHY_ANY,
296 	    MII_OFFSET_ANY, 0);
297 	if (LIST_FIRST(&sc->sc_mii.mii_phys) == NULL) {
298 		ifmedia_add(&sc->sc_mii.mii_media, IFM_ETHER | IFM_MANUAL,
299 		    0, NULL);
300 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER | IFM_MANUAL);
301 	} else {
302 		ifmedia_set(&sc->sc_mii.mii_media, IFM_ETHER | IFM_AUTO);
303 	}
304 
305 	if_attach(ifp);
306 	ether_ifattach(ifp, sc->sc_enaddr);
307 	ether_set_ifflags_cb(&sc->sc_ethercom, enet_ifflags_cb);
308 
309 	rnd_attach_source(&sc->sc_rnd_source, device_xname(sc->sc_dev),
310 	    RND_TYPE_NET, RND_FLAG_DEFAULT);
311 
312 #ifdef ENET_EVENT_COUNTER
313 	enet_attach_evcnt(sc);
314 #endif
315 
316 	sc->sc_stopping = false;
317 
318 	return;
319 
320  failure:
321 	bus_space_unmap(sc->sc_iot, sc->sc_ioh, size);
322 	return;
323 }
324 
325 #ifdef ENET_EVENT_COUNTER
326 static void
327 enet_attach_evcnt(struct enet_softc *sc)
328 {
329 	const char *xname;
330 
331 	xname = device_xname(sc->sc_dev);
332 
333 #define ENET_EVCNT_ATTACH(name)	\
334 	evcnt_attach_dynamic(&sc->sc_ev_ ## name, EVCNT_TYPE_MISC,	\
335 	    NULL, xname, #name);
336 
337 	ENET_EVCNT_ATTACH(t_drop);
338 	ENET_EVCNT_ATTACH(t_packets);
339 	ENET_EVCNT_ATTACH(t_bc_pkt);
340 	ENET_EVCNT_ATTACH(t_mc_pkt);
341 	ENET_EVCNT_ATTACH(t_crc_align);
342 	ENET_EVCNT_ATTACH(t_undersize);
343 	ENET_EVCNT_ATTACH(t_oversize);
344 	ENET_EVCNT_ATTACH(t_frag);
345 	ENET_EVCNT_ATTACH(t_jab);
346 	ENET_EVCNT_ATTACH(t_col);
347 	ENET_EVCNT_ATTACH(t_p64);
348 	ENET_EVCNT_ATTACH(t_p65to127n);
349 	ENET_EVCNT_ATTACH(t_p128to255n);
350 	ENET_EVCNT_ATTACH(t_p256to511);
351 	ENET_EVCNT_ATTACH(t_p512to1023);
352 	ENET_EVCNT_ATTACH(t_p1024to2047);
353 	ENET_EVCNT_ATTACH(t_p_gte2048);
354 	ENET_EVCNT_ATTACH(t_octets);
355 	ENET_EVCNT_ATTACH(r_packets);
356 	ENET_EVCNT_ATTACH(r_bc_pkt);
357 	ENET_EVCNT_ATTACH(r_mc_pkt);
358 	ENET_EVCNT_ATTACH(r_crc_align);
359 	ENET_EVCNT_ATTACH(r_undersize);
360 	ENET_EVCNT_ATTACH(r_oversize);
361 	ENET_EVCNT_ATTACH(r_frag);
362 	ENET_EVCNT_ATTACH(r_jab);
363 	ENET_EVCNT_ATTACH(r_p64);
364 	ENET_EVCNT_ATTACH(r_p65to127);
365 	ENET_EVCNT_ATTACH(r_p128to255);
366 	ENET_EVCNT_ATTACH(r_p256to511);
367 	ENET_EVCNT_ATTACH(r_p512to1023);
368 	ENET_EVCNT_ATTACH(r_p1024to2047);
369 	ENET_EVCNT_ATTACH(r_p_gte2048);
370 	ENET_EVCNT_ATTACH(r_octets);
371 }
372 
373 static void
374 enet_update_evcnt(struct enet_softc *sc)
375 {
376 	sc->sc_ev_t_drop.ev_count += ENET_REG_READ(sc, ENET_RMON_T_DROP);
377 	sc->sc_ev_t_packets.ev_count += ENET_REG_READ(sc, ENET_RMON_T_PACKETS);
378 	sc->sc_ev_t_bc_pkt.ev_count += ENET_REG_READ(sc, ENET_RMON_T_BC_PKT);
379 	sc->sc_ev_t_mc_pkt.ev_count += ENET_REG_READ(sc, ENET_RMON_T_MC_PKT);
380 	sc->sc_ev_t_crc_align.ev_count += ENET_REG_READ(sc, ENET_RMON_T_CRC_ALIGN);
381 	sc->sc_ev_t_undersize.ev_count += ENET_REG_READ(sc, ENET_RMON_T_UNDERSIZE);
382 	sc->sc_ev_t_oversize.ev_count += ENET_REG_READ(sc, ENET_RMON_T_OVERSIZE);
383 	sc->sc_ev_t_frag.ev_count += ENET_REG_READ(sc, ENET_RMON_T_FRAG);
384 	sc->sc_ev_t_jab.ev_count += ENET_REG_READ(sc, ENET_RMON_T_JAB);
385 	sc->sc_ev_t_col.ev_count += ENET_REG_READ(sc, ENET_RMON_T_COL);
386 	sc->sc_ev_t_p64.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P64);
387 	sc->sc_ev_t_p65to127n.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P65TO127N);
388 	sc->sc_ev_t_p128to255n.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P128TO255N);
389 	sc->sc_ev_t_p256to511.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P256TO511);
390 	sc->sc_ev_t_p512to1023.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P512TO1023);
391 	sc->sc_ev_t_p1024to2047.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P1024TO2047);
392 	sc->sc_ev_t_p_gte2048.ev_count += ENET_REG_READ(sc, ENET_RMON_T_P_GTE2048);
393 	sc->sc_ev_t_octets.ev_count += ENET_REG_READ(sc, ENET_RMON_T_OCTETS);
394 	sc->sc_ev_r_packets.ev_count += ENET_REG_READ(sc, ENET_RMON_R_PACKETS);
395 	sc->sc_ev_r_bc_pkt.ev_count += ENET_REG_READ(sc, ENET_RMON_R_BC_PKT);
396 	sc->sc_ev_r_mc_pkt.ev_count += ENET_REG_READ(sc, ENET_RMON_R_MC_PKT);
397 	sc->sc_ev_r_crc_align.ev_count += ENET_REG_READ(sc, ENET_RMON_R_CRC_ALIGN);
398 	sc->sc_ev_r_undersize.ev_count += ENET_REG_READ(sc, ENET_RMON_R_UNDERSIZE);
399 	sc->sc_ev_r_oversize.ev_count += ENET_REG_READ(sc, ENET_RMON_R_OVERSIZE);
400 	sc->sc_ev_r_frag.ev_count += ENET_REG_READ(sc, ENET_RMON_R_FRAG);
401 	sc->sc_ev_r_jab.ev_count += ENET_REG_READ(sc, ENET_RMON_R_JAB);
402 	sc->sc_ev_r_p64.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P64);
403 	sc->sc_ev_r_p65to127.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P65TO127);
404 	sc->sc_ev_r_p128to255.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P128TO255);
405 	sc->sc_ev_r_p256to511.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P256TO511);
406 	sc->sc_ev_r_p512to1023.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P512TO1023);
407 	sc->sc_ev_r_p1024to2047.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P1024TO2047);
408 	sc->sc_ev_r_p_gte2048.ev_count += ENET_REG_READ(sc, ENET_RMON_R_P_GTE2048);
409 	sc->sc_ev_r_octets.ev_count += ENET_REG_READ(sc, ENET_RMON_R_OCTETS);
410 }
411 #endif /* ENET_EVENT_COUNTER */
412 
413 static void
414 enet_tick(void *arg)
415 {
416 	struct enet_softc *sc;
417 	struct mii_data *mii;
418 	struct ifnet *ifp;
419 	int s;
420 
421 	sc = arg;
422 	mii = &sc->sc_mii;
423 	ifp = &sc->sc_ethercom.ec_if;
424 
425 	s = splnet();
426 
427 	if (sc->sc_stopping)
428 		goto out;
429 
430 #ifdef ENET_EVENT_COUNTER
431 	enet_update_evcnt(sc);
432 #endif
433 
434 	/* update counters */
435 	ifp->if_ierrors += ENET_REG_READ(sc, ENET_RMON_R_UNDERSIZE);
436 	ifp->if_ierrors += ENET_REG_READ(sc, ENET_RMON_R_FRAG);
437 	ifp->if_ierrors += ENET_REG_READ(sc, ENET_RMON_R_JAB);
438 
439 	/* clear counters */
440 	ENET_REG_WRITE(sc, ENET_MIBC, ENET_MIBC_MIB_CLEAR);
441 	ENET_REG_WRITE(sc, ENET_MIBC, 0);
442 
443 	mii_tick(mii);
444  out:
445 
446 	if (!sc->sc_stopping)
447 		callout_schedule(&sc->sc_tick_ch, ENET_TICK);
448 
449 	splx(s);
450 }
451 
452 static int
453 enet_intr(void *arg)
454 {
455 	struct enet_softc *sc;
456 	struct ifnet *ifp;
457 	uint32_t status;
458 
459 	sc = arg;
460 	status = ENET_REG_READ(sc, ENET_EIR);
461 
462 	if (sc->sc_imxtype == 7) {
463 		if (status & (ENET_EIR_TXF|ENET_EIR_TXF1|ENET_EIR_TXF2))
464 			enet_tx_intr(arg);
465 		if (status & (ENET_EIR_RXF|ENET_EIR_RXF1|ENET_EIR_RXF2))
466 			enet_rx_intr(arg);
467 	} else {
468 		if (status & ENET_EIR_TXF)
469 			enet_tx_intr(arg);
470 		if (status & ENET_EIR_RXF)
471 			enet_rx_intr(arg);
472 	}
473 
474 	if (status & ENET_EIR_EBERR) {
475 		device_printf(sc->sc_dev, "Ethernet Bus Error\n");
476 		ifp = &sc->sc_ethercom.ec_if;
477 		enet_stop(ifp, 1);
478 		enet_init(ifp);
479 	} else {
480 		ENET_REG_WRITE(sc, ENET_EIR, status);
481 	}
482 
483 	rnd_add_uint32(&sc->sc_rnd_source, status);
484 
485 	return 1;
486 }
487 
488 static int
489 enet_tx_intr(void *arg)
490 {
491 	struct enet_softc *sc;
492 	struct ifnet *ifp;
493 	struct enet_txsoft *txs;
494 	int idx;
495 
496 	sc = (struct enet_softc *)arg;
497 	ifp = &sc->sc_ethercom.ec_if;
498 
499 	for (idx = sc->sc_tx_considx; idx != sc->sc_tx_prodidx;
500 	    idx = ENET_TX_NEXTIDX(idx)) {
501 
502 		txs = &sc->sc_txsoft[idx];
503 
504 		TXDESC_READIN(idx);
505 		if (sc->sc_txdesc_ring[idx].tx_flags1_len & TXFLAGS1_R) {
506 			/* This TX Descriptor has not been transmitted yet */
507 			break;
508 		}
509 
510 		/* txsoft is available on first segment (TXFLAGS1_T1) */
511 		if (sc->sc_txdesc_ring[idx].tx_flags1_len & TXFLAGS1_T1) {
512 			bus_dmamap_unload(sc->sc_dmat,
513 			    txs->txs_dmamap);
514 			m_freem(txs->txs_mbuf);
515 			ifp->if_opackets++;
516 		}
517 
518 		/* checking error */
519 		if (sc->sc_txdesc_ring[idx].tx_flags1_len & TXFLAGS1_L) {
520 			uint32_t flags2;
521 
522 			flags2 = sc->sc_txdesc_ring[idx].tx_flags2;
523 
524 			if (flags2 & (TXFLAGS2_TXE |
525 			    TXFLAGS2_UE | TXFLAGS2_EE | TXFLAGS2_FE |
526 			    TXFLAGS2_LCE | TXFLAGS2_OE | TXFLAGS2_TSE)) {
527 #ifdef DEBUG_ENET
528 				if (enet_debug) {
529 					char flagsbuf[128];
530 
531 					snprintb(flagsbuf, sizeof(flagsbuf),
532 					    "\20" "\20TRANSMIT" "\16UNDERFLOW"
533 					    "\15COLLISION" "\14FRAME"
534 					    "\13LATECOLLISION" "\12OVERFLOW",
535 					    flags2);
536 
537 					device_printf(sc->sc_dev,
538 					    "txdesc[%d]: transmit error: "
539 					    "flags2=%s\n", idx, flagsbuf);
540 				}
541 #endif /* DEBUG_ENET */
542 				ifp->if_oerrors++;
543 			}
544 		}
545 
546 		sc->sc_tx_free++;
547 	}
548 	sc->sc_tx_considx = idx;
549 
550 	if (sc->sc_tx_free > 0)
551 		ifp->if_flags &= ~IFF_OACTIVE;
552 
553 	/*
554 	 * No more pending TX descriptor,
555 	 * cancel the watchdog timer.
556 	 */
557 	if (sc->sc_tx_free == ENET_TX_RING_CNT)
558 		ifp->if_timer = 0;
559 
560 	return 1;
561 }
562 
563 static int
564 enet_rx_intr(void *arg)
565 {
566 	struct enet_softc *sc;
567 	struct ifnet *ifp;
568 	struct enet_rxsoft *rxs;
569 	int idx, len, amount;
570 	uint32_t flags1, flags2;
571 	struct mbuf *m, *m0, *mprev;
572 
573 	sc = arg;
574 	ifp = &sc->sc_ethercom.ec_if;
575 
576 	m0 = mprev = NULL;
577 	amount = 0;
578 	for (idx = sc->sc_rx_readidx; ; idx = ENET_RX_NEXTIDX(idx)) {
579 
580 		rxs = &sc->sc_rxsoft[idx];
581 
582 		RXDESC_READIN(idx);
583 		if (sc->sc_rxdesc_ring[idx].rx_flags1_len & RXFLAGS1_E) {
584 			/* This RX Descriptor has not been received yet */
585 			break;
586 		}
587 
588 		/*
589 		 * build mbuf from RX Descriptor if needed
590 		 */
591 		m = rxs->rxs_mbuf;
592 		rxs->rxs_mbuf = NULL;
593 
594 		flags1 = sc->sc_rxdesc_ring[idx].rx_flags1_len;
595 		len = RXFLAGS1_LEN(flags1);
596 
597 #define RACC_SHIFT16	2
598 		if (m0 == NULL) {
599 			m0 = m;
600 			m_adj(m0, RACC_SHIFT16);
601 			len -= RACC_SHIFT16;
602 			m->m_len = len;
603 			amount = len;
604 		} else {
605 			if (flags1 & RXFLAGS1_L)
606 				len = len - amount - RACC_SHIFT16;
607 
608 			m->m_len = len;
609 			amount += len;
610 			m->m_flags &= ~M_PKTHDR;
611 			mprev->m_next = m;
612 		}
613 		mprev = m;
614 
615 		flags2 = sc->sc_rxdesc_ring[idx].rx_flags2;
616 
617 		if (flags1 & RXFLAGS1_L) {
618 			/* last buffer */
619 			if ((amount < ETHER_HDR_LEN) ||
620 			    ((flags1 & (RXFLAGS1_LG | RXFLAGS1_NO |
621 			    RXFLAGS1_CR | RXFLAGS1_OV | RXFLAGS1_TR)) ||
622 			    (flags2 & (RXFLAGS2_ME | RXFLAGS2_PE |
623 			    RXFLAGS2_CE)))) {
624 
625 #ifdef DEBUG_ENET
626 				if (enet_debug) {
627 					char flags1buf[128], flags2buf[128];
628 					snprintb(flags1buf, sizeof(flags1buf),
629 					    "\20" "\31MISS" "\26LENGTHVIOLATION"
630 					    "\25NONOCTET" "\23CRC" "\22OVERRUN"
631 					    "\21TRUNCATED", flags1);
632 					snprintb(flags2buf, sizeof(flags2buf),
633 					    "\20" "\40MAC" "\33PHY"
634 					    "\32COLLISION", flags2);
635 
636 					DEVICE_DPRINTF(
637 					    "rxdesc[%d]: receive error: "
638 					    "flags1=%s,flags2=%s,len=%d\n",
639 					    idx, flags1buf, flags2buf, amount);
640 				}
641 #endif /* DEBUG_ENET */
642 				ifp->if_ierrors++;
643 				m_freem(m0);
644 
645 			} else {
646 				/* packet receive ok */
647 				m_set_rcvif(m0, ifp);
648 				m0->m_pkthdr.len = amount;
649 
650 				bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
651 				    rxs->rxs_dmamap->dm_mapsize,
652 				    BUS_DMASYNC_PREREAD);
653 
654 				if (ifp->if_csum_flags_rx & (M_CSUM_IPv4 |
655 				    M_CSUM_TCPv4 | M_CSUM_UDPv4 |
656 				    M_CSUM_TCPv6 | M_CSUM_UDPv6))
657 					enet_rx_csum(sc, ifp, m0, idx);
658 
659 				if_percpuq_enqueue(ifp->if_percpuq, m0);
660 			}
661 
662 			m0 = NULL;
663 			mprev = NULL;
664 			amount = 0;
665 
666 		} else {
667 			/* continued from previous buffer */
668 			bus_dmamap_sync(sc->sc_dmat, rxs->rxs_dmamap, 0,
669 			    rxs->rxs_dmamap->dm_mapsize, BUS_DMASYNC_PREREAD);
670 		}
671 
672 		bus_dmamap_unload(sc->sc_dmat, rxs->rxs_dmamap);
673 		if (enet_alloc_rxbuf(sc, idx) != 0) {
674 			panic("enet_alloc_rxbuf NULL\n");
675 		}
676 	}
677 	sc->sc_rx_readidx = idx;
678 
679 	/* re-enable RX DMA to make sure */
680 	ENET_REG_WRITE(sc, ENET_RDAR, ENET_RDAR_ACTIVE);
681 
682 	return 1;
683 }
684 
685 static void
686 enet_rx_csum(struct enet_softc *sc, struct ifnet *ifp, struct mbuf *m, int idx)
687 {
688 	uint32_t flags2;
689 	uint8_t proto;
690 
691 	flags2 = sc->sc_rxdesc_ring[idx].rx_flags2;
692 
693 	if (flags2 & RXFLAGS2_IPV6) {
694 		proto = sc->sc_rxdesc_ring[idx].rx_proto;
695 
696 		/* RXFLAGS2_PCR is valid when IPv6 and TCP/UDP */
697 		if ((proto == IPPROTO_TCP) &&
698 		    (ifp->if_csum_flags_rx & M_CSUM_TCPv6))
699 			m->m_pkthdr.csum_flags |= M_CSUM_TCPv6;
700 		else if ((proto == IPPROTO_UDP) &&
701 		    (ifp->if_csum_flags_rx & M_CSUM_UDPv6))
702 			m->m_pkthdr.csum_flags |= M_CSUM_UDPv6;
703 		else
704 			return;
705 
706 		/* IPv6 protocol checksum error */
707 		if (flags2 & RXFLAGS2_PCR)
708 			m->m_pkthdr.csum_flags |= M_CSUM_TCP_UDP_BAD;
709 
710 	} else {
711 		struct ether_header *eh;
712 		uint8_t *ip;
713 
714 		eh = mtod(m, struct ether_header *);
715 
716 		/* XXX: is an IPv4? */
717 		if (ntohs(eh->ether_type) != ETHERTYPE_IP)
718 			return;
719 		ip = (uint8_t *)(eh + 1);
720 		if ((ip[0] & 0xf0) == 0x40)
721 			return;
722 
723 		proto = sc->sc_rxdesc_ring[idx].rx_proto;
724 		if (flags2 & RXFLAGS2_ICE) {
725 			if (ifp->if_csum_flags_rx & M_CSUM_IPv4) {
726 				m->m_pkthdr.csum_flags |=
727 				    M_CSUM_IPv4 | M_CSUM_IPv4_BAD;
728 			}
729 		} else {
730 			if (ifp->if_csum_flags_rx & M_CSUM_IPv4) {
731 				m->m_pkthdr.csum_flags |= M_CSUM_IPv4;
732 			}
733 
734 			/*
735 			 * PCR is valid when
736 			 * ICE == 0 and FRAG == 0
737 			 */
738 			if (flags2 & RXFLAGS2_FRAG)
739 				return;
740 
741 			/*
742 			 * PCR is valid when proto is TCP or UDP
743 			 */
744 			if ((proto == IPPROTO_TCP) &&
745 			    (ifp->if_csum_flags_rx & M_CSUM_TCPv4))
746 				m->m_pkthdr.csum_flags |= M_CSUM_TCPv4;
747 			else if ((proto == IPPROTO_UDP) &&
748 			    (ifp->if_csum_flags_rx & M_CSUM_UDPv4))
749 				m->m_pkthdr.csum_flags |= M_CSUM_UDPv4;
750 			else
751 				return;
752 
753 			/* IPv4 protocol cksum error */
754 			if (flags2 & RXFLAGS2_PCR)
755 				m->m_pkthdr.csum_flags |= M_CSUM_TCP_UDP_BAD;
756 		}
757 	}
758 }
759 
760 static void
761 enet_setmulti(struct enet_softc *sc)
762 {
763 	struct ifnet *ifp;
764 	struct ether_multi *enm;
765 	struct ether_multistep step;
766 	int promisc;
767 	uint32_t crc;
768 	uint32_t gaddr[2];
769 
770 	ifp = &sc->sc_ethercom.ec_if;
771 
772 	promisc = 0;
773 	if ((ifp->if_flags & IFF_PROMISC) || sc->sc_ethercom.ec_multicnt > 0) {
774 		ifp->if_flags |= IFF_ALLMULTI;
775 		if (ifp->if_flags & IFF_PROMISC)
776 			promisc = 1;
777 		gaddr[0] = gaddr[1] = 0xffffffff;
778 	} else {
779 		gaddr[0] = gaddr[1] = 0;
780 
781 		ETHER_FIRST_MULTI(step, &sc->sc_ethercom, enm);
782 		while (enm != NULL) {
783 			crc = ether_crc32_le(enm->enm_addrlo, ETHER_ADDR_LEN);
784 			gaddr[crc >> 31] |= 1 << ((crc >> 26) & 0x1f);
785 			ETHER_NEXT_MULTI(step, enm);
786 		}
787 	}
788 
789 	ENET_REG_WRITE(sc, ENET_GAUR, gaddr[0]);
790 	ENET_REG_WRITE(sc, ENET_GALR, gaddr[1]);
791 
792 	if (promisc) {
793 		/* match all packet */
794 		ENET_REG_WRITE(sc, ENET_IAUR, 0xffffffff);
795 		ENET_REG_WRITE(sc, ENET_IALR, 0xffffffff);
796 	} else {
797 		/* don't match any packet */
798 		ENET_REG_WRITE(sc, ENET_IAUR, 0);
799 		ENET_REG_WRITE(sc, ENET_IALR, 0);
800 	}
801 }
802 
803 static void
804 enet_gethwaddr(struct enet_softc *sc, uint8_t *hwaddr)
805 {
806 	uint32_t paddr;
807 
808 	paddr = ENET_REG_READ(sc, ENET_PALR);
809 	hwaddr[0] = paddr >> 24;
810 	hwaddr[1] = paddr >> 16;
811 	hwaddr[2] = paddr >> 8;
812 	hwaddr[3] = paddr;
813 
814 	paddr = ENET_REG_READ(sc, ENET_PAUR);
815 	hwaddr[4] = paddr >> 24;
816 	hwaddr[5] = paddr >> 16;
817 }
818 
819 static void
820 enet_sethwaddr(struct enet_softc *sc, uint8_t *hwaddr)
821 {
822 	uint32_t paddr;
823 
824 	paddr = (hwaddr[0] << 24) | (hwaddr[1] << 16) | (hwaddr[2] << 8) |
825 	    hwaddr[3];
826 	ENET_REG_WRITE(sc, ENET_PALR, paddr);
827 	paddr = (hwaddr[4] << 24) | (hwaddr[5] << 16);
828 	ENET_REG_WRITE(sc, ENET_PAUR, paddr);
829 }
830 
831 /*
832  * ifnet interfaces
833  */
834 static int
835 enet_init(struct ifnet *ifp)
836 {
837 	struct enet_softc *sc;
838 	int s, error;
839 
840 	sc = ifp->if_softc;
841 
842 	s = splnet();
843 
844 	enet_init_regs(sc, 0);
845 	enet_init_txring(sc);
846 	error = enet_init_rxring(sc);
847 	if (error != 0) {
848 		enet_drain_rxbuf(sc);
849 		device_printf(sc->sc_dev, "Cannot allocate mbuf cluster\n");
850 		goto init_failure;
851 	}
852 
853 	/* reload mac address */
854 	memcpy(sc->sc_enaddr, CLLADDR(ifp->if_sadl), ETHER_ADDR_LEN);
855 	enet_sethwaddr(sc, sc->sc_enaddr);
856 
857 	/* program multicast address */
858 	enet_setmulti(sc);
859 
860 	/* update if_flags */
861 	ifp->if_flags |= IFF_RUNNING;
862 	ifp->if_flags &= ~IFF_OACTIVE;
863 
864 	/* update local copy of if_flags */
865 	sc->sc_if_flags = ifp->if_flags;
866 
867 	/* mii */
868 	mii_mediachg(&sc->sc_mii);
869 
870 	/* enable RX DMA */
871 	ENET_REG_WRITE(sc, ENET_RDAR, ENET_RDAR_ACTIVE);
872 
873 	sc->sc_stopping = false;
874 	callout_schedule(&sc->sc_tick_ch, ENET_TICK);
875 
876  init_failure:
877 	splx(s);
878 
879 	return error;
880 }
881 
882 static void
883 enet_start(struct ifnet *ifp)
884 {
885 	struct enet_softc *sc;
886 	struct mbuf *m;
887 	int npkt;
888 
889 	if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
890 		return;
891 
892 	sc = ifp->if_softc;
893 	for (npkt = 0; ; npkt++) {
894 		IFQ_POLL(&ifp->if_snd, m);
895 		if (m == NULL)
896 			break;
897 
898 		if (sc->sc_tx_free <= 0) {
899 			/* no tx descriptor now... */
900 			ifp->if_flags |= IFF_OACTIVE;
901 			DEVICE_DPRINTF("TX descriptor is full\n");
902 			break;
903 		}
904 
905 		IFQ_DEQUEUE(&ifp->if_snd, m);
906 
907 		if (enet_encap_txring(sc, &m) != 0) {
908 			/* too many mbuf chains? */
909 			ifp->if_flags |= IFF_OACTIVE;
910 			DEVICE_DPRINTF(
911 			    "TX descriptor is full. dropping packet\n");
912 			m_freem(m);
913 			ifp->if_oerrors++;
914 			break;
915 		}
916 
917 		/* Pass the packet to any BPF listeners */
918 		bpf_mtap(ifp, m);
919 	}
920 
921 	if (npkt) {
922 		/* enable TX DMA */
923 		ENET_REG_WRITE(sc, ENET_TDAR, ENET_TDAR_ACTIVE);
924 
925 		ifp->if_timer = 5;
926 	}
927 }
928 
929 static void
930 enet_stop(struct ifnet *ifp, int disable)
931 {
932 	struct enet_softc *sc;
933 	int s;
934 	uint32_t v;
935 
936 	sc = ifp->if_softc;
937 
938 	s = splnet();
939 
940 	sc->sc_stopping = true;
941 	callout_stop(&sc->sc_tick_ch);
942 
943 	/* clear ENET_ECR[ETHEREN] to abort receive and transmit */
944 	v = ENET_REG_READ(sc, ENET_ECR);
945 	ENET_REG_WRITE(sc, ENET_ECR, v & ~ENET_ECR_ETHEREN);
946 
947 	/* Mark the interface as down and cancel the watchdog timer. */
948 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
949 	ifp->if_timer = 0;
950 
951 	if (disable) {
952 		enet_drain_txbuf(sc);
953 		enet_drain_rxbuf(sc);
954 	}
955 
956 	splx(s);
957 }
958 
959 static void
960 enet_watchdog(struct ifnet *ifp)
961 {
962 	struct enet_softc *sc;
963 	int s;
964 
965 	sc = ifp->if_softc;
966 	s = splnet();
967 
968 	device_printf(sc->sc_dev, "watchdog timeout\n");
969 	ifp->if_oerrors++;
970 
971 	/* salvage packets left in descriptors */
972 	enet_tx_intr(sc);
973 	enet_rx_intr(sc);
974 
975 	/* reset */
976 	enet_stop(ifp, 1);
977 	enet_init(ifp);
978 
979 	splx(s);
980 }
981 
982 static void
983 enet_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
984 {
985 	struct enet_softc *sc = ifp->if_softc;
986 
987 	ether_mediastatus(ifp, ifmr);
988 	ifmr->ifm_active = (ifmr->ifm_active & ~IFM_ETH_FMASK)
989 	    | sc->sc_flowflags;
990 }
991 
992 static int
993 enet_ifflags_cb(struct ethercom *ec)
994 {
995 	struct ifnet *ifp = &ec->ec_if;
996 	struct enet_softc *sc = ifp->if_softc;
997 	int change = ifp->if_flags ^ sc->sc_if_flags;
998 
999 	if ((change & ~(IFF_CANTCHANGE | IFF_DEBUG)) != 0)
1000 		return ENETRESET;
1001 	else if ((change & (IFF_PROMISC | IFF_ALLMULTI)) == 0)
1002 		return 0;
1003 
1004 	enet_setmulti(sc);
1005 
1006 	sc->sc_if_flags = ifp->if_flags;
1007 	return 0;
1008 }
1009 
1010 static int
1011 enet_ioctl(struct ifnet *ifp, u_long command, void *data)
1012 {
1013 	struct enet_softc *sc;
1014 	struct ifreq *ifr;
1015 	int s, error;
1016 	uint32_t v;
1017 
1018 	sc = ifp->if_softc;
1019 	ifr = data;
1020 
1021 	error = 0;
1022 
1023 	s = splnet();
1024 
1025 	switch (command) {
1026 	case SIOCSIFMTU:
1027 		if (MTU2FRAMESIZE(ifr->ifr_mtu) > ENET_MAX_PKT_LEN) {
1028 			error = EINVAL;
1029 		} else {
1030 			ifp->if_mtu = ifr->ifr_mtu;
1031 
1032 			/* set maximum frame length */
1033 			v = MTU2FRAMESIZE(ifr->ifr_mtu);
1034 			ENET_REG_WRITE(sc, ENET_FTRL, v);
1035 			v = ENET_REG_READ(sc, ENET_RCR);
1036 			v &= ~ENET_RCR_MAX_FL(0x3fff);
1037 			v |= ENET_RCR_MAX_FL(ifp->if_mtu + ETHER_HDR_LEN +
1038 			    ETHER_CRC_LEN + ETHER_VLAN_ENCAP_LEN);
1039 			ENET_REG_WRITE(sc, ENET_RCR, v);
1040 		}
1041 		break;
1042 	case SIOCSIFMEDIA:
1043 	case SIOCGIFMEDIA:
1044 		/* Flow control requires full-duplex mode. */
1045 		if (IFM_SUBTYPE(ifr->ifr_media) == IFM_AUTO ||
1046 		    (ifr->ifr_media & IFM_FDX) == 0)
1047 			ifr->ifr_media &= ~IFM_ETH_FMASK;
1048 		if (IFM_SUBTYPE(ifr->ifr_media) != IFM_AUTO) {
1049 			if ((ifr->ifr_media & IFM_ETH_FMASK) == IFM_FLOW) {
1050 				/* We can do both TXPAUSE and RXPAUSE. */
1051 				ifr->ifr_media |=
1052 				    IFM_ETH_TXPAUSE | IFM_ETH_RXPAUSE;
1053 			}
1054 			sc->sc_flowflags = ifr->ifr_media & IFM_ETH_FMASK;
1055 		}
1056 		error = ifmedia_ioctl(ifp, ifr, &sc->sc_mii.mii_media, command);
1057 		break;
1058 	default:
1059 		error = ether_ioctl(ifp, command, data);
1060 		if (error != ENETRESET)
1061 			break;
1062 
1063 		/* post-process */
1064 		error = 0;
1065 		switch (command) {
1066 		case SIOCSIFCAP:
1067 			error = (*ifp->if_init)(ifp);
1068 			break;
1069 		case SIOCADDMULTI:
1070 		case SIOCDELMULTI:
1071 			if (ifp->if_flags & IFF_RUNNING)
1072 				enet_setmulti(sc);
1073 			break;
1074 		}
1075 		break;
1076 	}
1077 
1078 	splx(s);
1079 
1080 	return error;
1081 }
1082 
1083 /*
1084  * for MII
1085  */
1086 static int
1087 enet_miibus_readreg(device_t dev, int phy, int reg)
1088 {
1089 	struct enet_softc *sc;
1090 	int timeout;
1091 	uint32_t val, status;
1092 
1093 	sc = device_private(dev);
1094 
1095 	/* clear MII update */
1096 	ENET_REG_WRITE(sc, ENET_EIR, ENET_EIR_MII);
1097 
1098 	/* read command */
1099 	ENET_REG_WRITE(sc, ENET_MMFR,
1100 	    ENET_MMFR_ST | ENET_MMFR_OP_READ | ENET_MMFR_TA |
1101 	    ENET_MMFR_PHY_REG(reg) | ENET_MMFR_PHY_ADDR(phy));
1102 
1103 	/* check MII update */
1104 	for (timeout = 5000; timeout > 0; --timeout) {
1105 		status = ENET_REG_READ(sc, ENET_EIR);
1106 		if (status & ENET_EIR_MII)
1107 			break;
1108 	}
1109 	if (timeout <= 0) {
1110 		DEVICE_DPRINTF("MII read timeout: reg=0x%02x\n",
1111 		    reg);
1112 		val = -1;
1113 	} else {
1114 		val = ENET_REG_READ(sc, ENET_MMFR) & ENET_MMFR_DATAMASK;
1115 	}
1116 
1117 	return val;
1118 }
1119 
1120 static void
1121 enet_miibus_writereg(device_t dev, int phy, int reg, int val)
1122 {
1123 	struct enet_softc *sc;
1124 	int timeout;
1125 
1126 	sc = device_private(dev);
1127 
1128 	/* clear MII update */
1129 	ENET_REG_WRITE(sc, ENET_EIR, ENET_EIR_MII);
1130 
1131 	/* write command */
1132 	ENET_REG_WRITE(sc, ENET_MMFR,
1133 	    ENET_MMFR_ST | ENET_MMFR_OP_WRITE | ENET_MMFR_TA |
1134 	    ENET_MMFR_PHY_REG(reg) | ENET_MMFR_PHY_ADDR(phy) |
1135 	    (ENET_MMFR_DATAMASK & val));
1136 
1137 	/* check MII update */
1138 	for (timeout = 5000; timeout > 0; --timeout) {
1139 		if (ENET_REG_READ(sc, ENET_EIR) & ENET_EIR_MII)
1140 			break;
1141 	}
1142 	if (timeout <= 0) {
1143 		DEVICE_DPRINTF("MII write timeout: reg=0x%02x\n",
1144 		    reg);
1145 	}
1146 }
1147 
1148 static void
1149 enet_miibus_statchg(struct ifnet *ifp)
1150 {
1151 	struct enet_softc *sc;
1152 	struct mii_data *mii;
1153 	struct ifmedia_entry *ife;
1154 	uint32_t ecr, ecr0;
1155 	uint32_t rcr, rcr0;
1156 	uint32_t tcr, tcr0;
1157 
1158 	sc = ifp->if_softc;
1159 	mii = &sc->sc_mii;
1160 	ife = mii->mii_media.ifm_cur;
1161 
1162 	/* get current status */
1163 	ecr0 = ecr = ENET_REG_READ(sc, ENET_ECR) & ~ENET_ECR_RESET;
1164 	rcr0 = rcr = ENET_REG_READ(sc, ENET_RCR);
1165 	tcr0 = tcr = ENET_REG_READ(sc, ENET_TCR);
1166 
1167 	if (IFM_SUBTYPE(mii->mii_media.ifm_cur->ifm_media) == IFM_AUTO &&
1168 	    (mii->mii_media_active & IFM_ETH_FMASK) != sc->sc_flowflags) {
1169 		sc->sc_flowflags = mii->mii_media_active & IFM_ETH_FMASK;
1170 		mii->mii_media_active &= ~IFM_ETH_FMASK;
1171 	}
1172 
1173 	if ((ife->ifm_media & IFM_GMASK) == IFM_FDX) {
1174 		tcr |= ENET_TCR_FDEN;	/* full duplex */
1175 		rcr &= ~ENET_RCR_DRT;;	/* enable receive on transmit */
1176 	} else {
1177 		tcr &= ~ENET_TCR_FDEN;	/* half duplex */
1178 		rcr |= ENET_RCR_DRT;	/* disable receive on transmit */
1179 	}
1180 
1181 	if ((tcr ^ tcr0) & ENET_TCR_FDEN) {
1182 		/*
1183 		 * need to reset because
1184 		 * FDEN can change when ECR[ETHEREN] is 0
1185 		 */
1186 		enet_init_regs(sc, 0);
1187 		return;
1188 	}
1189 
1190 	switch (IFM_SUBTYPE(ife->ifm_media)) {
1191 	case IFM_AUTO:
1192 	case IFM_1000_T:
1193 		ecr |= ENET_ECR_SPEED;		/* 1000Mbps mode */
1194 		rcr &= ~ENET_RCR_RMII_10T;
1195 		break;
1196 	case IFM_100_TX:
1197 		ecr &= ~ENET_ECR_SPEED;		/* 100Mbps mode */
1198 		rcr &= ~ENET_RCR_RMII_10T;	/* 100Mbps mode */
1199 		break;
1200 	case IFM_10_T:
1201 		ecr &= ~ENET_ECR_SPEED;		/* 10Mbps mode */
1202 		rcr |= ENET_RCR_RMII_10T;	/* 10Mbps mode */
1203 		break;
1204 	default:
1205 		ecr = ecr0;
1206 		rcr = rcr0;
1207 		tcr = tcr0;
1208 		break;
1209 	}
1210 
1211 	if (sc->sc_rgmii == 0)
1212 		ecr &= ~ENET_ECR_SPEED;
1213 
1214 	if (sc->sc_flowflags & IFM_FLOW)
1215 		rcr |= ENET_RCR_FCE;
1216 	else
1217 		rcr &= ~ENET_RCR_FCE;
1218 
1219 	/* update registers if need change */
1220 	if (ecr != ecr0)
1221 		ENET_REG_WRITE(sc, ENET_ECR, ecr);
1222 	if (rcr != rcr0)
1223 		ENET_REG_WRITE(sc, ENET_RCR, rcr);
1224 	if (tcr != tcr0)
1225 		ENET_REG_WRITE(sc, ENET_TCR, tcr);
1226 }
1227 
1228 /*
1229  * handling descriptors
1230  */
1231 static void
1232 enet_init_txring(struct enet_softc *sc)
1233 {
1234 	int i;
1235 
1236 	/* build TX ring */
1237 	for (i = 0; i < ENET_TX_RING_CNT; i++) {
1238 		sc->sc_txdesc_ring[i].tx_flags1_len =
1239 		    ((i == (ENET_TX_RING_CNT - 1)) ? TXFLAGS1_W : 0);
1240 		sc->sc_txdesc_ring[i].tx_databuf = 0;
1241 		sc->sc_txdesc_ring[i].tx_flags2 = TXFLAGS2_INT;
1242 		sc->sc_txdesc_ring[i].tx__reserved1 = 0;
1243 		sc->sc_txdesc_ring[i].tx_flags3 = 0;
1244 		sc->sc_txdesc_ring[i].tx_1588timestamp = 0;
1245 		sc->sc_txdesc_ring[i].tx__reserved2 = 0;
1246 		sc->sc_txdesc_ring[i].tx__reserved3 = 0;
1247 
1248 		TXDESC_WRITEOUT(i);
1249 	}
1250 
1251 	sc->sc_tx_free = ENET_TX_RING_CNT;
1252 	sc->sc_tx_considx = 0;
1253 	sc->sc_tx_prodidx = 0;
1254 }
1255 
1256 static int
1257 enet_init_rxring(struct enet_softc *sc)
1258 {
1259 	int i, error;
1260 
1261 	/* build RX ring */
1262 	for (i = 0; i < ENET_RX_RING_CNT; i++) {
1263 		error = enet_alloc_rxbuf(sc, i);
1264 		if (error != 0)
1265 			return error;
1266 	}
1267 
1268 	sc->sc_rx_readidx = 0;
1269 
1270 	return 0;
1271 }
1272 
1273 static int
1274 enet_alloc_rxbuf(struct enet_softc *sc, int idx)
1275 {
1276 	struct mbuf *m;
1277 	int error;
1278 
1279 	KASSERT((idx >= 0) && (idx < ENET_RX_RING_CNT));
1280 
1281 	/* free mbuf if already allocated */
1282 	if (sc->sc_rxsoft[idx].rxs_mbuf != NULL) {
1283 		bus_dmamap_unload(sc->sc_dmat, sc->sc_rxsoft[idx].rxs_dmamap);
1284 		m_freem(sc->sc_rxsoft[idx].rxs_mbuf);
1285 		sc->sc_rxsoft[idx].rxs_mbuf = NULL;
1286 	}
1287 
1288 	/* allocate new mbuf cluster */
1289 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1290 	if (m == NULL)
1291 		return ENOBUFS;
1292 	MCLGET(m, M_DONTWAIT);
1293 	if (!(m->m_flags & M_EXT)) {
1294 		m_freem(m);
1295 		return ENOBUFS;
1296 	}
1297 	m->m_len = MCLBYTES;
1298 	m->m_next = NULL;
1299 
1300 	error = bus_dmamap_load(sc->sc_dmat, sc->sc_rxsoft[idx].rxs_dmamap,
1301 	    m->m_ext.ext_buf, m->m_ext.ext_size, NULL,
1302 	    BUS_DMA_READ | BUS_DMA_NOWAIT);
1303 	if (error) {
1304 		m_freem(m);
1305 		return error;
1306 	}
1307 
1308 	bus_dmamap_sync(sc->sc_dmat, sc->sc_rxsoft[idx].rxs_dmamap, 0,
1309 	    sc->sc_rxsoft[idx].rxs_dmamap->dm_mapsize,
1310 	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1311 
1312 	sc->sc_rxsoft[idx].rxs_mbuf = m;
1313 	enet_reset_rxdesc(sc, idx);
1314 	return 0;
1315 }
1316 
1317 static void
1318 enet_reset_rxdesc(struct enet_softc *sc, int idx)
1319 {
1320 	uint32_t paddr;
1321 
1322 	paddr = sc->sc_rxsoft[idx].rxs_dmamap->dm_segs[0].ds_addr;
1323 
1324 	sc->sc_rxdesc_ring[idx].rx_flags1_len =
1325 	    RXFLAGS1_E |
1326 	    ((idx == (ENET_RX_RING_CNT - 1)) ? RXFLAGS1_W : 0);
1327 	sc->sc_rxdesc_ring[idx].rx_databuf = paddr;
1328 	sc->sc_rxdesc_ring[idx].rx_flags2 =
1329 	    RXFLAGS2_INT;
1330 	sc->sc_rxdesc_ring[idx].rx_hl = 0;
1331 	sc->sc_rxdesc_ring[idx].rx_proto = 0;
1332 	sc->sc_rxdesc_ring[idx].rx_cksum = 0;
1333 	sc->sc_rxdesc_ring[idx].rx_flags3 = 0;
1334 	sc->sc_rxdesc_ring[idx].rx_1588timestamp = 0;
1335 	sc->sc_rxdesc_ring[idx].rx__reserved2 = 0;
1336 	sc->sc_rxdesc_ring[idx].rx__reserved3 = 0;
1337 
1338 	RXDESC_WRITEOUT(idx);
1339 }
1340 
1341 static void
1342 enet_drain_txbuf(struct enet_softc *sc)
1343 {
1344 	int idx;
1345 	struct enet_txsoft *txs;
1346 	struct ifnet *ifp;
1347 
1348 	ifp = &sc->sc_ethercom.ec_if;
1349 
1350 	for (idx = sc->sc_tx_considx; idx != sc->sc_tx_prodidx;
1351 	    idx = ENET_TX_NEXTIDX(idx)) {
1352 
1353 		/* txsoft[] is used only first segment */
1354 		txs = &sc->sc_txsoft[idx];
1355 		TXDESC_READIN(idx);
1356 		if (sc->sc_txdesc_ring[idx].tx_flags1_len & TXFLAGS1_T1) {
1357 			sc->sc_txdesc_ring[idx].tx_flags1_len = 0;
1358 			bus_dmamap_unload(sc->sc_dmat,
1359 			    txs->txs_dmamap);
1360 			m_freem(txs->txs_mbuf);
1361 
1362 			ifp->if_oerrors++;
1363 		}
1364 		sc->sc_tx_free++;
1365 	}
1366 }
1367 
1368 static void
1369 enet_drain_rxbuf(struct enet_softc *sc)
1370 {
1371 	int i;
1372 
1373 	for (i = 0; i < ENET_RX_RING_CNT; i++) {
1374 		if (sc->sc_rxsoft[i].rxs_mbuf != NULL) {
1375 			sc->sc_rxdesc_ring[i].rx_flags1_len = 0;
1376 			bus_dmamap_unload(sc->sc_dmat,
1377 			    sc->sc_rxsoft[i].rxs_dmamap);
1378 			m_freem(sc->sc_rxsoft[i].rxs_mbuf);
1379 			sc->sc_rxsoft[i].rxs_mbuf = NULL;
1380 		}
1381 	}
1382 }
1383 
1384 static int
1385 enet_alloc_ring(struct enet_softc *sc)
1386 {
1387 	int i, error;
1388 
1389 	/*
1390 	 * build DMA maps for TX.
1391 	 * TX descriptor must be able to contain mbuf chains,
1392 	 * so, make up ENET_MAX_PKT_NSEGS dmamap.
1393 	 */
1394 	for (i = 0; i < ENET_TX_RING_CNT; i++) {
1395 		error = bus_dmamap_create(sc->sc_dmat, ENET_MAX_PKT_LEN,
1396 		    ENET_MAX_PKT_NSEGS, ENET_MAX_PKT_LEN, 0, BUS_DMA_NOWAIT,
1397 		    &sc->sc_txsoft[i].txs_dmamap);
1398 
1399 		if (error) {
1400 			aprint_error_dev(sc->sc_dev,
1401 			    "can't create DMA map for TX descs\n");
1402 			goto fail_1;
1403 		}
1404 	}
1405 
1406 	/*
1407 	 * build DMA maps for RX.
1408 	 * RX descripter contains An mbuf cluster,
1409 	 * and make up a dmamap.
1410 	 */
1411 	for (i = 0; i < ENET_RX_RING_CNT; i++) {
1412 		error = bus_dmamap_create(sc->sc_dmat, MCLBYTES,
1413 		    1, MCLBYTES, 0, BUS_DMA_NOWAIT,
1414 		    &sc->sc_rxsoft[i].rxs_dmamap);
1415 		if (error) {
1416 			aprint_error_dev(sc->sc_dev,
1417 			    "can't create DMA map for RX descs\n");
1418 			goto fail_2;
1419 		}
1420 	}
1421 
1422 	if (enet_alloc_dma(sc, sizeof(struct enet_txdesc) * ENET_TX_RING_CNT,
1423 	    (void **)&(sc->sc_txdesc_ring), &(sc->sc_txdesc_dmamap)) != 0)
1424 		return -1;
1425 	memset(sc->sc_txdesc_ring, 0,
1426 	    sizeof(struct enet_txdesc) * ENET_TX_RING_CNT);
1427 
1428 	if (enet_alloc_dma(sc, sizeof(struct enet_rxdesc) * ENET_RX_RING_CNT,
1429 	    (void **)&(sc->sc_rxdesc_ring), &(sc->sc_rxdesc_dmamap)) != 0)
1430 		return -1;
1431 	memset(sc->sc_rxdesc_ring, 0,
1432 	    sizeof(struct enet_rxdesc) * ENET_RX_RING_CNT);
1433 
1434 	return 0;
1435 
1436  fail_2:
1437 	for (i = 0; i < ENET_RX_RING_CNT; i++) {
1438 		if (sc->sc_rxsoft[i].rxs_dmamap != NULL)
1439 			bus_dmamap_destroy(sc->sc_dmat,
1440 			    sc->sc_rxsoft[i].rxs_dmamap);
1441 	}
1442  fail_1:
1443 	for (i = 0; i < ENET_TX_RING_CNT; i++) {
1444 		if (sc->sc_txsoft[i].txs_dmamap != NULL)
1445 			bus_dmamap_destroy(sc->sc_dmat,
1446 			    sc->sc_txsoft[i].txs_dmamap);
1447 	}
1448 	return error;
1449 }
1450 
1451 static int
1452 enet_encap_mbufalign(struct mbuf **mp)
1453 {
1454 	struct mbuf *m, *m0, *mt, *p, *x;
1455 	void *ap;
1456 	uint32_t alignoff, chiplen;
1457 
1458 	/*
1459 	 * iMX6 SoC ethernet controller requires
1460 	 * address of buffer must aligned 8, and
1461 	 * length of buffer must be greater than 10 (first fragment only?)
1462 	 */
1463 #define ALIGNBYTE	8
1464 #define MINBUFSIZE	10
1465 #define ALIGN_PTR(p, align)	\
1466 	(void *)(((uintptr_t)(p) + ((align) - 1)) & -(align))
1467 
1468 	m0 = *mp;
1469 	mt = p = NULL;
1470 	for (m = m0; m != NULL; m = m->m_next) {
1471 		alignoff = (uintptr_t)m->m_data & (ALIGNBYTE - 1);
1472 		if (m->m_len < (ALIGNBYTE * 2)) {
1473 			/*
1474 			 * rearrange mbuf data aligned
1475 			 *
1476 			 *        align 8 *       *       *       *       *
1477 			 *               +0123456789abcdef0123456789abcdef0
1478 			 * FROM m->m_data[___________abcdefghijklmn_______]
1479 			 *
1480 			 *               +0123456789abcdef0123456789abcdef0
1481 			 * TO   m->m_data[________abcdefghijklm___________] or
1482 			 *      m->m_data[________________abcdefghijklmn__]
1483 			 */
1484 			if ((alignoff != 0) && (m->m_len != 0)) {
1485 				chiplen = ALIGNBYTE - alignoff;
1486 				if (M_LEADINGSPACE(m) >= alignoff) {
1487 					ap = m->m_data - alignoff;
1488 					memmove(ap, m->m_data, m->m_len);
1489 					m->m_data = ap;
1490 				} else if (M_TRAILINGSPACE(m) >= chiplen) {
1491 					ap = m->m_data + chiplen;
1492 					memmove(ap, m->m_data, m->m_len);
1493 					m->m_data = ap;
1494 				} else {
1495 					/*
1496 					 * no space to align data. (M_READONLY?)
1497 					 * allocate new mbuf aligned,
1498 					 * and copy to it.
1499 					 */
1500 					MGET(x, M_DONTWAIT, m->m_type);
1501 					if (x == NULL) {
1502 						m_freem(m);
1503 						return ENOBUFS;
1504 					}
1505 					MCLAIM(x, m->m_owner);
1506 					if (m->m_flags & M_PKTHDR)
1507 						M_MOVE_PKTHDR(x, m);
1508 					x->m_len = m->m_len;
1509 					x->m_data = ALIGN_PTR(x->m_data,
1510 					    ALIGNBYTE);
1511 					memcpy(mtod(x, void *), mtod(m, void *),
1512 					    m->m_len);
1513 					p->m_next = x;
1514 					x->m_next = m_free(m);
1515 					m = x;
1516 				}
1517 			}
1518 
1519 			/*
1520 			 * fill 1st mbuf at least 10byte
1521 			 *
1522 			 *        align 8 *       *       *       *       *
1523 			 *               +0123456789abcdef0123456789abcdef0
1524 			 * FROM m->m_data[________abcde___________________]
1525 			 *      m->m_data[__fg____________________________]
1526 			 *      m->m_data[_________________hi_____________]
1527 			 *      m->m_data[__________jk____________________]
1528 			 *      m->m_data[____l___________________________]
1529 			 *
1530 			 *               +0123456789abcdef0123456789abcdef0
1531 			 * TO   m->m_data[________abcdefghij______________]
1532 			 *      m->m_data[________________________________]
1533 			 *      m->m_data[________________________________]
1534 			 *      m->m_data[___________k____________________]
1535 			 *      m->m_data[____l___________________________]
1536 			 */
1537 			if (mt == NULL) {
1538 				mt = m;
1539 				while (mt->m_len == 0) {
1540 					mt = mt->m_next;
1541 					if (mt == NULL) {
1542 						m_freem(m);
1543 						return ENOBUFS;
1544 					}
1545 				}
1546 
1547 				/* mt = 1st mbuf, x = 2nd mbuf */
1548 				x = mt->m_next;
1549 				while (mt->m_len < MINBUFSIZE) {
1550 					if (x == NULL) {
1551 						m_freem(m);
1552 						return ENOBUFS;
1553 					}
1554 
1555 					alignoff = (uintptr_t)x->m_data &
1556 					    (ALIGNBYTE - 1);
1557 					chiplen = ALIGNBYTE - alignoff;
1558 					if (chiplen > x->m_len) {
1559 						chiplen = x->m_len;
1560 					} else if ((mt->m_len + chiplen) <
1561 					    MINBUFSIZE) {
1562 						/*
1563 						 * next mbuf should be greater
1564 						 * than ALIGNBYTE?
1565 						 */
1566 						if (x->m_len >= (chiplen +
1567 						    ALIGNBYTE * 2))
1568 							chiplen += ALIGNBYTE;
1569 						else
1570 							chiplen = x->m_len;
1571 					}
1572 
1573 					if (chiplen &&
1574 					    (M_TRAILINGSPACE(mt) < chiplen)) {
1575 						/*
1576 						 * move data to the begining of
1577 						 * m_dat[] (aligned) to en-
1578 						 * large trailingspace
1579 						 */
1580 						if (mt->m_flags & M_EXT) {
1581 							ap = mt->m_ext.ext_buf;
1582 						} else if (mt->m_flags &
1583 						    M_PKTHDR) {
1584 							ap = mt->m_pktdat;
1585 						} else {
1586 							ap = mt->m_dat;
1587 						}
1588 						ap = ALIGN_PTR(ap, ALIGNBYTE);
1589 						memcpy(ap, mt->m_data,
1590 						    mt->m_len);
1591 						mt->m_data = ap;
1592 					}
1593 
1594 					if (chiplen &&
1595 					    (M_TRAILINGSPACE(mt) >= chiplen)) {
1596 						memcpy(mt->m_data + mt->m_len,
1597 						    x->m_data, chiplen);
1598 						mt->m_len += chiplen;
1599 						m_adj(x, chiplen);
1600 					}
1601 
1602 					x = x->m_next;
1603 				}
1604 			}
1605 
1606 		} else {
1607 			mt = m;
1608 
1609 			/*
1610 			 * allocate new mbuf x, and rearrange as below;
1611 			 *
1612 			 *        align 8 *       *       *       *       *
1613 			 *               +0123456789abcdef0123456789abcdef0
1614 			 * FROM m->m_data[____________abcdefghijklmnopq___]
1615 			 *
1616 			 *               +0123456789abcdef0123456789abcdef0
1617 			 * TO   x->m_data[________abcdefghijkl____________]
1618 			 *      m->m_data[________________________mnopq___]
1619 			 *
1620 			 */
1621 			if (alignoff != 0) {
1622 				/* at least ALIGNBYTE */
1623 				chiplen = ALIGNBYTE - alignoff + ALIGNBYTE;
1624 
1625 				MGET(x, M_DONTWAIT, m->m_type);
1626 				if (x == NULL) {
1627 					m_freem(m);
1628 					return ENOBUFS;
1629 				}
1630 				MCLAIM(x, m->m_owner);
1631 				if (m->m_flags & M_PKTHDR)
1632 					M_MOVE_PKTHDR(x, m);
1633 				x->m_data = ALIGN_PTR(x->m_data, ALIGNBYTE);
1634 				memcpy(mtod(x, void *), mtod(m, void *),
1635 				    chiplen);
1636 				x->m_len = chiplen;
1637 				x->m_next = m;
1638 				m_adj(m, chiplen);
1639 
1640 				if (p == NULL)
1641 					m0 = x;
1642 				else
1643 					p->m_next = x;
1644 			}
1645 		}
1646 		p = m;
1647 	}
1648 	*mp = m0;
1649 
1650 	return 0;
1651 }
1652 
1653 static int
1654 enet_encap_txring(struct enet_softc *sc, struct mbuf **mp)
1655 {
1656 	bus_dmamap_t map;
1657 	struct mbuf *m;
1658 	int csumflags, idx, i, error;
1659 	uint32_t flags1, flags2;
1660 
1661 	idx = sc->sc_tx_prodidx;
1662 	map = sc->sc_txsoft[idx].txs_dmamap;
1663 
1664 	/* align mbuf data for claim of ENET */
1665 	error = enet_encap_mbufalign(mp);
1666 	if (error != 0)
1667 		return error;
1668 
1669 	m = *mp;
1670 	csumflags = m->m_pkthdr.csum_flags;
1671 
1672 	error = bus_dmamap_load_mbuf(sc->sc_dmat, map, m,
1673 	    BUS_DMA_NOWAIT);
1674 	if (error != 0) {
1675 		device_printf(sc->sc_dev,
1676 		    "Error mapping mbuf into TX chain: error=%d\n", error);
1677 		m_freem(m);
1678 		return error;
1679 	}
1680 
1681 	if (map->dm_nsegs > sc->sc_tx_free) {
1682 		bus_dmamap_unload(sc->sc_dmat, map);
1683 		device_printf(sc->sc_dev,
1684 		    "too many mbuf chain %d\n", map->dm_nsegs);
1685 		m_freem(m);
1686 		return ENOBUFS;
1687 	}
1688 
1689 	/* fill protocol cksum zero beforehand */
1690 	if (csumflags & (M_CSUM_UDPv4 | M_CSUM_TCPv4 |
1691 	    M_CSUM_UDPv6 | M_CSUM_TCPv6)) {
1692 		struct mbuf *m1;
1693 		int ehlen, moff;
1694 		uint16_t etype;
1695 
1696 		m_copydata(m, ETHER_ADDR_LEN * 2, sizeof(etype), &etype);
1697 		switch (ntohs(etype)) {
1698 		case ETHERTYPE_IP:
1699 		case ETHERTYPE_IPV6:
1700 			ehlen = ETHER_HDR_LEN;
1701 			break;
1702 		case ETHERTYPE_VLAN:
1703 			ehlen = ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN;
1704 			break;
1705 		default:
1706 			ehlen = 0;
1707 			break;
1708 		}
1709 
1710 		if (ehlen) {
1711 			m1 = m_getptr(m, ehlen +
1712 			    M_CSUM_DATA_IPv4_IPHL(m->m_pkthdr.csum_data) +
1713 			    M_CSUM_DATA_IPv4_OFFSET(m->m_pkthdr.csum_data),
1714 			    &moff);
1715 			if (m1 != NULL)
1716 				*(uint16_t *)(mtod(m1, char *) + moff) = 0;
1717 		}
1718 	}
1719 
1720 	bus_dmamap_sync(sc->sc_dmat, map, 0, map->dm_mapsize,
1721 	    BUS_DMASYNC_PREWRITE);
1722 
1723 	for (i = 0; i < map->dm_nsegs; i++) {
1724 		flags1 = TXFLAGS1_R;
1725 		flags2 = 0;
1726 
1727 		if (i == 0) {
1728 			flags1 |= TXFLAGS1_T1;	/* mark as first segment */
1729 			sc->sc_txsoft[idx].txs_mbuf = m;
1730 		}
1731 
1732 		/* checksum offloading */
1733 		if (csumflags & (M_CSUM_UDPv4 | M_CSUM_TCPv4 |
1734 		    M_CSUM_UDPv6 | M_CSUM_TCPv6))
1735 			flags2 |= TXFLAGS2_PINS;
1736 		if (csumflags & (M_CSUM_IPv4))
1737 			flags2 |= TXFLAGS2_IINS;
1738 
1739 		if (i == map->dm_nsegs - 1) {
1740 			/* mark last segment */
1741 			flags1 |= TXFLAGS1_L | TXFLAGS1_TC;
1742 			flags2 |= TXFLAGS2_INT;
1743 		}
1744 		if (idx == ENET_TX_RING_CNT - 1) {
1745 			/* mark end of ring */
1746 			flags1 |= TXFLAGS1_W;
1747 		}
1748 
1749 		sc->sc_txdesc_ring[idx].tx_databuf = map->dm_segs[i].ds_addr;
1750 		sc->sc_txdesc_ring[idx].tx_flags2 = flags2;
1751 		sc->sc_txdesc_ring[idx].tx_flags3 = 0;
1752 		TXDESC_WRITEOUT(idx);
1753 
1754 		sc->sc_txdesc_ring[idx].tx_flags1_len =
1755 		    flags1 | TXFLAGS1_LEN(map->dm_segs[i].ds_len);
1756 		TXDESC_WRITEOUT(idx);
1757 
1758 		idx = ENET_TX_NEXTIDX(idx);
1759 		sc->sc_tx_free--;
1760 	}
1761 
1762 	sc->sc_tx_prodidx = idx;
1763 
1764 	return 0;
1765 }
1766 
1767 /*
1768  * device initialize
1769  */
1770 static int
1771 enet_init_regs(struct enet_softc *sc, int init)
1772 {
1773 	struct mii_data *mii;
1774 	struct ifmedia_entry *ife;
1775 	paddr_t paddr;
1776 	uint32_t val;
1777 	int miimode, fulldup, ecr_speed, rcr_speed, flowctrl;
1778 
1779 	if (init) {
1780 		fulldup = 1;
1781 		ecr_speed = ENET_ECR_SPEED;
1782 		rcr_speed = 0;
1783 		flowctrl = 0;
1784 	} else {
1785 		mii = &sc->sc_mii;
1786 		ife = mii->mii_media.ifm_cur;
1787 
1788 		if ((ife->ifm_media & IFM_GMASK) == IFM_FDX)
1789 			fulldup = 1;
1790 		else
1791 			fulldup = 0;
1792 
1793 		switch (IFM_SUBTYPE(ife->ifm_media)) {
1794 		case IFM_10_T:
1795 			ecr_speed = 0;
1796 			rcr_speed = ENET_RCR_RMII_10T;
1797 			break;
1798 		case IFM_100_TX:
1799 			ecr_speed = 0;
1800 			rcr_speed = 0;
1801 			break;
1802 		default:
1803 			ecr_speed = ENET_ECR_SPEED;
1804 			rcr_speed = 0;
1805 			break;
1806 		}
1807 
1808 		flowctrl = sc->sc_flowflags & IFM_FLOW;
1809 	}
1810 
1811 	if (sc->sc_rgmii == 0)
1812 		ecr_speed = 0;
1813 
1814 	/* reset */
1815 	ENET_REG_WRITE(sc, ENET_ECR, ecr_speed | ENET_ECR_RESET);
1816 
1817 	/* mask and clear all interrupt */
1818 	ENET_REG_WRITE(sc, ENET_EIMR, 0);
1819 	ENET_REG_WRITE(sc, ENET_EIR, 0xffffffff);
1820 
1821 	/* full duplex */
1822 	ENET_REG_WRITE(sc, ENET_TCR, fulldup ? ENET_TCR_FDEN : 0);
1823 
1824 	/* clear and enable MIB register */
1825 	ENET_REG_WRITE(sc, ENET_MIBC, ENET_MIBC_MIB_CLEAR);
1826 	ENET_REG_WRITE(sc, ENET_MIBC, 0);
1827 
1828 	/* MII speed setup. MDCclk(=2.5MHz) = ENET_PLL/((val+1)*2) */
1829 	val = ((sc->sc_pllclock) / 500000 - 1) / 10;
1830 	ENET_REG_WRITE(sc, ENET_MSCR, val << 1);
1831 
1832 	/* Opcode/Pause Duration */
1833 	ENET_REG_WRITE(sc, ENET_OPD, 0x00010020);
1834 
1835 	/* Receive FIFO */
1836 	ENET_REG_WRITE(sc, ENET_RSFL, 16);	/* RxFIFO Section Full */
1837 	ENET_REG_WRITE(sc, ENET_RSEM, 0x84);	/* RxFIFO Section Empty */
1838 	ENET_REG_WRITE(sc, ENET_RAEM, 8);	/* RxFIFO Almost Empty */
1839 	ENET_REG_WRITE(sc, ENET_RAFL, 8);	/* RxFIFO Almost Full */
1840 
1841 	/* Transmit FIFO */
1842 	ENET_REG_WRITE(sc, ENET_TFWR, ENET_TFWR_STRFWD |
1843 	    ENET_TFWR_FIFO(128));		/* TxFIFO Watermark */
1844 	ENET_REG_WRITE(sc, ENET_TSEM, 0);	/* TxFIFO Section Empty */
1845 	ENET_REG_WRITE(sc, ENET_TAEM, 256);	/* TxFIFO Almost Empty */
1846 	ENET_REG_WRITE(sc, ENET_TAFL, 8);	/* TxFIFO Almost Full */
1847 	ENET_REG_WRITE(sc, ENET_TIPG, 12);	/* Tx Inter-Packet Gap */
1848 
1849 	/* hardware checksum is default off (override in TX descripter) */
1850 	ENET_REG_WRITE(sc, ENET_TACC, 0);
1851 
1852 	/*
1853 	 * align ethernet payload on 32bit, discard frames with MAC layer error,
1854 	 * and don't discard checksum error
1855 	 */
1856 	ENET_REG_WRITE(sc, ENET_RACC, ENET_RACC_SHIFT16 | ENET_RACC_LINEDIS);
1857 
1858 	/* maximum frame size */
1859 	val = ENET_DEFAULT_PKT_LEN;
1860 	ENET_REG_WRITE(sc, ENET_FTRL, val);	/* Frame Truncation Length */
1861 
1862 	if (sc->sc_rgmii == 0)
1863 		miimode = ENET_RCR_RMII_MODE | ENET_RCR_MII_MODE;
1864 	else
1865 		miimode = ENET_RCR_RGMII_EN;
1866 	ENET_REG_WRITE(sc, ENET_RCR,
1867 	    ENET_RCR_PADEN |			/* RX frame padding remove */
1868 	    miimode |
1869 	    (flowctrl ? ENET_RCR_FCE : 0) |	/* flow control enable */
1870 	    rcr_speed |
1871 	    (fulldup ? 0 : ENET_RCR_DRT) |
1872 	    ENET_RCR_MAX_FL(val));
1873 
1874 	/* Maximum Receive BufSize per one descriptor */
1875 	ENET_REG_WRITE(sc, ENET_MRBR, RXDESC_MAXBUFSIZE);
1876 
1877 
1878 	/* TX/RX Descriptor Physical Address */
1879 	paddr = sc->sc_txdesc_dmamap->dm_segs[0].ds_addr;
1880 	ENET_REG_WRITE(sc, ENET_TDSR, paddr);
1881 	paddr = sc->sc_rxdesc_dmamap->dm_segs[0].ds_addr;
1882 	ENET_REG_WRITE(sc, ENET_RDSR, paddr);
1883 	/* sync cache */
1884 	bus_dmamap_sync(sc->sc_dmat, sc->sc_txdesc_dmamap, 0,
1885 	    sc->sc_txdesc_dmamap->dm_mapsize, BUS_DMASYNC_PREWRITE);
1886 	bus_dmamap_sync(sc->sc_dmat, sc->sc_rxdesc_dmamap, 0,
1887 	    sc->sc_rxdesc_dmamap->dm_mapsize, BUS_DMASYNC_PREWRITE);
1888 
1889 	/* enable interrupts */
1890 	val = ENET_EIMR|ENET_EIR_TXF|ENET_EIR_RXF|ENET_EIR_EBERR;
1891 	if (sc->sc_imxtype == 7)
1892 		val |= ENET_EIR_TXF2|ENET_EIR_RXF2|ENET_EIR_TXF1|ENET_EIR_RXF1;
1893 	ENET_REG_WRITE(sc, ENET_EIMR, val);
1894 
1895 	/* enable ether */
1896 	ENET_REG_WRITE(sc, ENET_ECR,
1897 #if _BYTE_ORDER == _LITTLE_ENDIAN
1898 	    ENET_ECR_DBSWP |
1899 #endif
1900 	    ecr_speed |
1901 	    ENET_ECR_EN1588 |	/* use enhanced TX/RX descriptor */
1902 	    ENET_ECR_ETHEREN);	/* Ethernet Enable */
1903 
1904 	return 0;
1905 }
1906 
1907 static int
1908 enet_alloc_dma(struct enet_softc *sc, size_t size, void **addrp,
1909               bus_dmamap_t *mapp)
1910 {
1911 	bus_dma_segment_t seglist[1];
1912 	int nsegs, error;
1913 
1914 	if ((error = bus_dmamem_alloc(sc->sc_dmat, size, PAGE_SIZE, 0, seglist,
1915 	    1, &nsegs, M_NOWAIT)) != 0) {
1916 		device_printf(sc->sc_dev,
1917 		    "unable to allocate DMA buffer, error=%d\n", error);
1918 		goto fail_alloc;
1919 	}
1920 
1921 	if ((error = bus_dmamem_map(sc->sc_dmat, seglist, 1, size, addrp,
1922 	    BUS_DMA_NOWAIT | BUS_DMA_COHERENT)) != 0) {
1923 		device_printf(sc->sc_dev,
1924 		    "unable to map DMA buffer, error=%d\n",
1925 		    error);
1926 		goto fail_map;
1927 	}
1928 
1929 	if ((error = bus_dmamap_create(sc->sc_dmat, size, 1, size, 0,
1930 	    BUS_DMA_NOWAIT, mapp)) != 0) {
1931 		device_printf(sc->sc_dev,
1932 		    "unable to create DMA map, error=%d\n", error);
1933 		goto fail_create;
1934 	}
1935 
1936 	if ((error = bus_dmamap_load(sc->sc_dmat, *mapp, *addrp, size, NULL,
1937 	    BUS_DMA_NOWAIT)) != 0) {
1938 		aprint_error_dev(sc->sc_dev,
1939 		    "unable to load DMA map, error=%d\n", error);
1940 		goto fail_load;
1941 	}
1942 
1943 	return 0;
1944 
1945  fail_load:
1946 	bus_dmamap_destroy(sc->sc_dmat, *mapp);
1947  fail_create:
1948 	bus_dmamem_unmap(sc->sc_dmat, *addrp, size);
1949  fail_map:
1950 	bus_dmamem_free(sc->sc_dmat, seglist, 1);
1951  fail_alloc:
1952 	return error;
1953 }
1954