xref: /freebsd/sys/arm/allwinner/if_emac.c (revision 85f87cf491bec6f90948a85b10f5523ea24db9e3)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2013 Ganbold Tsagaankhuu <ganbold@freebsd.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 AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 /* A10/A20 EMAC driver */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/kernel.h>
39 #include <sys/module.h>
40 #include <sys/bus.h>
41 #include <sys/lock.h>
42 #include <sys/mbuf.h>
43 #include <sys/mutex.h>
44 #include <sys/rman.h>
45 #include <sys/socket.h>
46 #include <sys/sockio.h>
47 #include <sys/sysctl.h>
48 #include <sys/gpio.h>
49 
50 #include <machine/bus.h>
51 #include <machine/resource.h>
52 #include <machine/intr.h>
53 
54 #include <net/if.h>
55 #include <net/if_var.h>
56 #include <net/if_arp.h>
57 #include <net/if_dl.h>
58 #include <net/if_media.h>
59 #include <net/if_types.h>
60 #include <net/if_mib.h>
61 #include <net/ethernet.h>
62 #include <net/if_vlan_var.h>
63 
64 #ifdef INET
65 #include <netinet/in.h>
66 #include <netinet/in_systm.h>
67 #include <netinet/in_var.h>
68 #include <netinet/ip.h>
69 #endif
70 
71 #include <net/bpf.h>
72 #include <net/bpfdesc.h>
73 
74 #include <dev/ofw/ofw_bus.h>
75 #include <dev/ofw/ofw_bus_subr.h>
76 
77 #include <dev/mii/mii.h>
78 #include <dev/mii/miivar.h>
79 
80 #include <arm/allwinner/if_emacreg.h>
81 #include <arm/allwinner/aw_sid.h>
82 
83 #include <dev/extres/clk/clk.h>
84 
85 #include "miibus_if.h"
86 
87 #include "gpio_if.h"
88 
89 #include "a10_sramc.h"
90 
91 struct emac_softc {
92 	struct ifnet		*emac_ifp;
93 	device_t		emac_dev;
94 	device_t		emac_miibus;
95 	bus_space_handle_t	emac_handle;
96 	bus_space_tag_t		emac_tag;
97 	struct resource		*emac_res;
98 	struct resource		*emac_irq;
99 	void			*emac_intrhand;
100 	clk_t			emac_clk;
101 	int			emac_if_flags;
102 	struct mtx		emac_mtx;
103 	struct callout		emac_tick_ch;
104 	int			emac_watchdog_timer;
105 	int			emac_rx_process_limit;
106 	int			emac_link;
107 	uint32_t		emac_fifo_mask;
108 };
109 
110 static int	emac_probe(device_t);
111 static int	emac_attach(device_t);
112 static int	emac_detach(device_t);
113 static int	emac_shutdown(device_t);
114 static int	emac_suspend(device_t);
115 static int	emac_resume(device_t);
116 
117 static int	emac_sys_setup(struct emac_softc *);
118 static void	emac_reset(struct emac_softc *);
119 
120 static void	emac_init_locked(struct emac_softc *);
121 static void	emac_start_locked(struct ifnet *);
122 static void	emac_init(void *);
123 static void	emac_stop_locked(struct emac_softc *);
124 static void	emac_intr(void *);
125 static int	emac_ioctl(struct ifnet *, u_long, caddr_t);
126 
127 static void	emac_rxeof(struct emac_softc *, int);
128 static void	emac_txeof(struct emac_softc *, uint32_t);
129 
130 static int	emac_miibus_readreg(device_t, int, int);
131 static int	emac_miibus_writereg(device_t, int, int, int);
132 static void	emac_miibus_statchg(device_t);
133 
134 static int	emac_ifmedia_upd(struct ifnet *);
135 static void	emac_ifmedia_sts(struct ifnet *, struct ifmediareq *);
136 
137 static int	sysctl_int_range(SYSCTL_HANDLER_ARGS, int, int);
138 static int	sysctl_hw_emac_proc_limit(SYSCTL_HANDLER_ARGS);
139 
140 #define	EMAC_READ_REG(sc, reg)		\
141     bus_space_read_4(sc->emac_tag, sc->emac_handle, reg)
142 #define	EMAC_WRITE_REG(sc, reg, val)	\
143     bus_space_write_4(sc->emac_tag, sc->emac_handle, reg, val)
144 
145 static int
146 emac_sys_setup(struct emac_softc *sc)
147 {
148 	int error;
149 
150 	/* Activate EMAC clock. */
151 	error = clk_get_by_ofw_index(sc->emac_dev, 0, 0, &sc->emac_clk);
152 	if (error != 0) {
153 		device_printf(sc->emac_dev, "cannot get clock\n");
154 		return (error);
155 	}
156 	error = clk_enable(sc->emac_clk);
157 	if (error != 0) {
158 		device_printf(sc->emac_dev, "cannot enable clock\n");
159 		return (error);
160 	}
161 
162 	/* Map sram. */
163 	a10_map_to_emac();
164 
165 	return (0);
166 }
167 
168 static void
169 emac_get_hwaddr(struct emac_softc *sc, uint8_t *hwaddr)
170 {
171 	uint32_t val0, val1, rnd;
172 	u_char rootkey[16];
173 	size_t rootkey_size;
174 
175 	/*
176 	 * Try to get MAC address from running hardware.
177 	 * If there is something non-zero there just use it.
178 	 *
179 	 * Otherwise set the address to a convenient locally assigned address,
180 	 * using the SID rootkey.
181 	 * This is was uboot does so we end up with the same mac as if uboot
182 	 * did set it.
183 	 * If we can't get the root key, generate a random one,
184 	 * 'bsd' + random 24 low-order bits. 'b' is 0x62, which has the locally
185 	 * assigned bit set, and the broadcast/multicast bit clear.
186 	 */
187 	val0 = EMAC_READ_REG(sc, EMAC_MAC_A0);
188 	val1 = EMAC_READ_REG(sc, EMAC_MAC_A1);
189 	if ((val0 | val1) != 0 && (val0 | val1) != 0xffffff) {
190 		hwaddr[0] = (val1 >> 16) & 0xff;
191 		hwaddr[1] = (val1 >> 8) & 0xff;
192 		hwaddr[2] = (val1 >> 0) & 0xff;
193 		hwaddr[3] = (val0 >> 16) & 0xff;
194 		hwaddr[4] = (val0 >> 8) & 0xff;
195 		hwaddr[5] = (val0 >> 0) & 0xff;
196 	} else {
197 		rootkey_size = sizeof(rootkey);
198 		if (aw_sid_get_fuse(AW_SID_FUSE_ROOTKEY, rootkey,
199 		    &rootkey_size) == 0) {
200 			hwaddr[0] = 0x2;
201 			hwaddr[1] = rootkey[3];
202 			hwaddr[2] = rootkey[12];
203 			hwaddr[3] = rootkey[13];
204 			hwaddr[4] = rootkey[14];
205 			hwaddr[5] = rootkey[15];
206 		}
207 		else {
208 			rnd = arc4random() & 0x00ffffff;
209 			hwaddr[0] = 'b';
210 			hwaddr[1] = 's';
211 			hwaddr[2] = 'd';
212 			hwaddr[3] = (rnd >> 16) & 0xff;
213 			hwaddr[4] = (rnd >> 8) & 0xff;
214 			hwaddr[5] = (rnd >> 0) & 0xff;
215 		}
216 	}
217 	if (bootverbose)
218 		printf("MAC address: %s\n", ether_sprintf(hwaddr));
219 }
220 
221 static void
222 emac_set_rx_mode(struct emac_softc *sc)
223 {
224 	struct ifnet *ifp;
225 	struct ifmultiaddr *ifma;
226 	uint32_t h, hashes[2];
227 	uint32_t rcr = 0;
228 
229 	EMAC_ASSERT_LOCKED(sc);
230 
231 	ifp = sc->emac_ifp;
232 
233 	rcr = EMAC_READ_REG(sc, EMAC_RX_CTL);
234 
235 	/* Unicast packet and DA filtering */
236 	rcr |= EMAC_RX_UCAD;
237 	rcr |= EMAC_RX_DAF;
238 
239 	hashes[0] = 0;
240 	hashes[1] = 0;
241 	if (ifp->if_flags & IFF_ALLMULTI) {
242 		hashes[0] = 0xffffffff;
243 		hashes[1] = 0xffffffff;
244 	} else {
245 		if_maddr_rlock(ifp);
246 		CK_STAILQ_FOREACH(ifma, &sc->emac_ifp->if_multiaddrs, ifma_link) {
247 			if (ifma->ifma_addr->sa_family != AF_LINK)
248 				continue;
249 			h = ether_crc32_be(LLADDR((struct sockaddr_dl *)
250 			    ifma->ifma_addr), ETHER_ADDR_LEN) >> 26;
251 			hashes[h >> 5] |= 1 << (h & 0x1f);
252 		}
253 		if_maddr_runlock(ifp);
254 	}
255 	rcr |= EMAC_RX_MCO;
256 	rcr |= EMAC_RX_MHF;
257 	EMAC_WRITE_REG(sc, EMAC_RX_HASH0, hashes[0]);
258 	EMAC_WRITE_REG(sc, EMAC_RX_HASH1, hashes[1]);
259 
260 	if (ifp->if_flags & IFF_BROADCAST) {
261 		rcr |= EMAC_RX_BCO;
262 		rcr |= EMAC_RX_MCO;
263 	}
264 
265 	if (ifp->if_flags & IFF_PROMISC)
266 		rcr |= EMAC_RX_PA;
267 	else
268 		rcr |= EMAC_RX_UCAD;
269 
270 	EMAC_WRITE_REG(sc, EMAC_RX_CTL, rcr);
271 }
272 
273 static void
274 emac_reset(struct emac_softc *sc)
275 {
276 
277 	EMAC_WRITE_REG(sc, EMAC_CTL, 0);
278 	DELAY(200);
279 	EMAC_WRITE_REG(sc, EMAC_CTL, 1);
280 	DELAY(200);
281 }
282 
283 static void
284 emac_drain_rxfifo(struct emac_softc *sc)
285 {
286 	uint32_t data;
287 
288 	while (EMAC_READ_REG(sc, EMAC_RX_FBC) > 0)
289 		data = EMAC_READ_REG(sc, EMAC_RX_IO_DATA);
290 }
291 
292 static void
293 emac_txeof(struct emac_softc *sc, uint32_t status)
294 {
295 	struct ifnet *ifp;
296 
297 	EMAC_ASSERT_LOCKED(sc);
298 
299 	ifp = sc->emac_ifp;
300 	status &= (EMAC_TX_FIFO0 | EMAC_TX_FIFO1);
301 	sc->emac_fifo_mask &= ~status;
302 	if (status == (EMAC_TX_FIFO0 | EMAC_TX_FIFO1))
303 		if_inc_counter(ifp, IFCOUNTER_OPACKETS, 2);
304 	else
305 		if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
306 	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
307 
308 	/* Unarm watchdog timer if no TX */
309 	sc->emac_watchdog_timer = 0;
310 }
311 
312 static void
313 emac_rxeof(struct emac_softc *sc, int count)
314 {
315 	struct ifnet *ifp;
316 	struct mbuf *m, *m0;
317 	uint32_t reg_val, rxcount;
318 	int16_t len;
319 	uint16_t status;
320 	int i;
321 
322 	ifp = sc->emac_ifp;
323 	for (; count > 0 &&
324 	    (ifp->if_drv_flags & IFF_DRV_RUNNING) != 0; count--) {
325 		/*
326 		 * Race warning: The first packet might arrive with
327 		 * the interrupts disabled, but the second will fix
328 		 */
329 		rxcount = EMAC_READ_REG(sc, EMAC_RX_FBC);
330 		if (!rxcount) {
331 			/* Had one stuck? */
332 			rxcount = EMAC_READ_REG(sc, EMAC_RX_FBC);
333 			if (!rxcount)
334 				return;
335 		}
336 		/* Check packet header */
337 		reg_val = EMAC_READ_REG(sc, EMAC_RX_IO_DATA);
338 		if (reg_val != EMAC_PACKET_HEADER) {
339 			/* Packet header is wrong */
340 			if (bootverbose)
341 				if_printf(ifp, "wrong packet header\n");
342 			/* Disable RX */
343 			reg_val = EMAC_READ_REG(sc, EMAC_CTL);
344 			reg_val &= ~EMAC_CTL_RX_EN;
345 			EMAC_WRITE_REG(sc, EMAC_CTL, reg_val);
346 
347 			/* Flush RX FIFO */
348 			reg_val = EMAC_READ_REG(sc, EMAC_RX_CTL);
349 			reg_val |= EMAC_RX_FLUSH_FIFO;
350 			EMAC_WRITE_REG(sc, EMAC_RX_CTL, reg_val);
351 			for (i = 100; i > 0; i--) {
352 				DELAY(100);
353 				if ((EMAC_READ_REG(sc, EMAC_RX_CTL) &
354 				    EMAC_RX_FLUSH_FIFO) == 0)
355 					break;
356 			}
357 			if (i == 0) {
358 				device_printf(sc->emac_dev,
359 				    "flush FIFO timeout\n");
360 				/* Reinitialize controller */
361 				emac_init_locked(sc);
362 				return;
363 			}
364 			/* Enable RX */
365 			reg_val = EMAC_READ_REG(sc, EMAC_CTL);
366 			reg_val |= EMAC_CTL_RX_EN;
367 			EMAC_WRITE_REG(sc, EMAC_CTL, reg_val);
368 
369 			return;
370 		}
371 
372 		/* Get packet size and status */
373 		reg_val = EMAC_READ_REG(sc, EMAC_RX_IO_DATA);
374 		len = reg_val & 0xffff;
375 		status = (reg_val >> 16) & 0xffff;
376 
377 		if (len < 64 || (status & EMAC_PKT_OK) == 0) {
378 			if (bootverbose)
379 				if_printf(ifp,
380 				    "bad packet: len = %i status = %i\n",
381 				    len, status);
382 			if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
383 			emac_drain_rxfifo(sc);
384 			continue;
385 		}
386 #if 0
387 		if (status & (EMAC_CRCERR | EMAC_LENERR)) {
388 			good_packet = 0;
389 			if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
390 			if (status & EMAC_CRCERR)
391 				if_printf(ifp, "crc error\n");
392 			if (status & EMAC_LENERR)
393 				if_printf(ifp, "length error\n");
394 		}
395 #endif
396 		m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
397 		if (m == NULL) {
398 			emac_drain_rxfifo(sc);
399 			return;
400 		}
401 		m->m_len = m->m_pkthdr.len = MCLBYTES;
402 
403 		/* Copy entire frame to mbuf first. */
404 		bus_space_read_multi_4(sc->emac_tag, sc->emac_handle,
405 		    EMAC_RX_IO_DATA, mtod(m, uint32_t *), roundup2(len, 4) / 4);
406 
407 		m->m_pkthdr.rcvif = ifp;
408 		m->m_len = m->m_pkthdr.len = len - ETHER_CRC_LEN;
409 
410 		/*
411 		 * Emac controller needs strict aligment, so to avoid
412 		 * copying over an entire frame to align, we allocate
413 		 * a new mbuf and copy ethernet header + IP header to
414 		 * the new mbuf. The new mbuf is prepended into the
415 		 * existing mbuf chain.
416 		 */
417 		if (m->m_len <= (MHLEN - ETHER_HDR_LEN)) {
418 			bcopy(m->m_data, m->m_data + ETHER_HDR_LEN, m->m_len);
419 			m->m_data += ETHER_HDR_LEN;
420 		} else if (m->m_len <= (MCLBYTES - ETHER_HDR_LEN) &&
421 		    m->m_len > (MHLEN - ETHER_HDR_LEN)) {
422 			MGETHDR(m0, M_NOWAIT, MT_DATA);
423 			if (m0 != NULL) {
424 				len = ETHER_HDR_LEN + m->m_pkthdr.l2hlen;
425 				bcopy(m->m_data, m0->m_data, len);
426 				m->m_data += len;
427 				m->m_len -= len;
428 				m0->m_len = len;
429 				M_MOVE_PKTHDR(m0, m);
430 				m0->m_next = m;
431 				m = m0;
432 			} else {
433 				if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
434 				m_freem(m);
435 				m = NULL;
436 				continue;
437 			}
438 		} else if (m->m_len > EMAC_MAC_MAXF) {
439 			if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
440 			m_freem(m);
441 			m = NULL;
442 			continue;
443 		}
444 		if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
445 		EMAC_UNLOCK(sc);
446 		(*ifp->if_input)(ifp, m);
447 		EMAC_LOCK(sc);
448 	}
449 }
450 
451 static void
452 emac_watchdog(struct emac_softc *sc)
453 {
454 	struct ifnet *ifp;
455 
456 	EMAC_ASSERT_LOCKED(sc);
457 
458 	if (sc->emac_watchdog_timer == 0 || --sc->emac_watchdog_timer)
459 		return;
460 
461 	ifp = sc->emac_ifp;
462 
463 	if (sc->emac_link == 0) {
464 		if (bootverbose)
465 			if_printf(sc->emac_ifp, "watchdog timeout "
466 			    "(missed link)\n");
467 	} else
468 		if_printf(sc->emac_ifp, "watchdog timeout -- resetting\n");
469 
470 	if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
471 	ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
472 	emac_init_locked(sc);
473 	if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
474 		emac_start_locked(ifp);
475 }
476 
477 static void
478 emac_tick(void *arg)
479 {
480 	struct emac_softc *sc;
481 	struct mii_data *mii;
482 
483 	sc = (struct emac_softc *)arg;
484 	mii = device_get_softc(sc->emac_miibus);
485 	mii_tick(mii);
486 
487 	emac_watchdog(sc);
488 	callout_reset(&sc->emac_tick_ch, hz, emac_tick, sc);
489 }
490 
491 static void
492 emac_init(void *xcs)
493 {
494 	struct emac_softc *sc;
495 
496 	sc = (struct emac_softc *)xcs;
497 	EMAC_LOCK(sc);
498 	emac_init_locked(sc);
499 	EMAC_UNLOCK(sc);
500 }
501 
502 static void
503 emac_init_locked(struct emac_softc *sc)
504 {
505 	struct ifnet *ifp;
506 	struct mii_data *mii;
507 	uint32_t reg_val;
508 	uint8_t *eaddr;
509 
510 	EMAC_ASSERT_LOCKED(sc);
511 
512 	ifp = sc->emac_ifp;
513 	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
514 		return;
515 
516 	/* Flush RX FIFO */
517 	reg_val = EMAC_READ_REG(sc, EMAC_RX_CTL);
518 	reg_val |= EMAC_RX_FLUSH_FIFO;
519 	EMAC_WRITE_REG(sc, EMAC_RX_CTL, reg_val);
520 	DELAY(1);
521 
522 	/* Soft reset MAC */
523 	reg_val = EMAC_READ_REG(sc, EMAC_MAC_CTL0);
524 	reg_val &= (~EMAC_MAC_CTL0_SOFT_RST);
525 	EMAC_WRITE_REG(sc, EMAC_MAC_CTL0, reg_val);
526 
527 	/* Set MII clock */
528 	reg_val = EMAC_READ_REG(sc, EMAC_MAC_MCFG);
529 	reg_val &= (~(0xf << 2));
530 	reg_val |= (0xd << 2);
531 	EMAC_WRITE_REG(sc, EMAC_MAC_MCFG, reg_val);
532 
533 	/* Clear RX counter */
534 	EMAC_WRITE_REG(sc, EMAC_RX_FBC, 0);
535 
536 	/* Disable all interrupt and clear interrupt status */
537 	EMAC_WRITE_REG(sc, EMAC_INT_CTL, 0);
538 	reg_val = EMAC_READ_REG(sc, EMAC_INT_STA);
539 	EMAC_WRITE_REG(sc, EMAC_INT_STA, reg_val);
540 	DELAY(1);
541 
542 	/* Set up TX */
543 	reg_val = EMAC_READ_REG(sc, EMAC_TX_MODE);
544 	reg_val |= EMAC_TX_AB_M;
545 	reg_val &= EMAC_TX_TM;
546 	EMAC_WRITE_REG(sc, EMAC_TX_MODE, reg_val);
547 
548 	/* Set up RX */
549 	reg_val = EMAC_READ_REG(sc, EMAC_RX_CTL);
550 	reg_val |= EMAC_RX_SETUP;
551 	reg_val &= EMAC_RX_TM;
552 	EMAC_WRITE_REG(sc, EMAC_RX_CTL, reg_val);
553 
554 	/* Set up MAC CTL0. */
555 	reg_val = EMAC_READ_REG(sc, EMAC_MAC_CTL0);
556 	reg_val |= EMAC_MAC_CTL0_SETUP;
557 	EMAC_WRITE_REG(sc, EMAC_MAC_CTL0, reg_val);
558 
559 	/* Set up MAC CTL1. */
560 	reg_val = EMAC_READ_REG(sc, EMAC_MAC_CTL1);
561 	reg_val |= EMAC_MAC_CTL1_SETUP;
562 	EMAC_WRITE_REG(sc, EMAC_MAC_CTL1, reg_val);
563 
564 	/* Set up IPGT */
565 	EMAC_WRITE_REG(sc, EMAC_MAC_IPGT, EMAC_MAC_IPGT_FD);
566 
567 	/* Set up IPGR */
568 	EMAC_WRITE_REG(sc, EMAC_MAC_IPGR, EMAC_MAC_NBTB_IPG2 |
569 	    (EMAC_MAC_NBTB_IPG1 << 8));
570 
571 	/* Set up Collison window */
572 	EMAC_WRITE_REG(sc, EMAC_MAC_CLRT, EMAC_MAC_RM | (EMAC_MAC_CW << 8));
573 
574 	/* Set up Max Frame Length */
575 	EMAC_WRITE_REG(sc, EMAC_MAC_MAXF, EMAC_MAC_MFL);
576 
577 	/* Setup ethernet address */
578 	eaddr = IF_LLADDR(ifp);
579 	EMAC_WRITE_REG(sc, EMAC_MAC_A1, eaddr[0] << 16 |
580 	    eaddr[1] << 8 | eaddr[2]);
581 	EMAC_WRITE_REG(sc, EMAC_MAC_A0, eaddr[3] << 16 |
582 	    eaddr[4] << 8 | eaddr[5]);
583 
584 	/* Setup rx filter */
585 	emac_set_rx_mode(sc);
586 
587 	/* Enable RX/TX0/RX Hlevel interrupt */
588 	reg_val = EMAC_READ_REG(sc, EMAC_INT_CTL);
589 	reg_val |= EMAC_INT_EN;
590 	EMAC_WRITE_REG(sc, EMAC_INT_CTL, reg_val);
591 
592 	ifp->if_drv_flags |= IFF_DRV_RUNNING;
593 	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
594 
595 	sc->emac_link = 0;
596 
597 	/* Switch to the current media. */
598 	mii = device_get_softc(sc->emac_miibus);
599 	mii_mediachg(mii);
600 
601 	callout_reset(&sc->emac_tick_ch, hz, emac_tick, sc);
602 }
603 
604 
605 static void
606 emac_start(struct ifnet *ifp)
607 {
608 	struct emac_softc *sc;
609 
610 	sc = ifp->if_softc;
611 	EMAC_LOCK(sc);
612 	emac_start_locked(ifp);
613 	EMAC_UNLOCK(sc);
614 }
615 
616 static void
617 emac_start_locked(struct ifnet *ifp)
618 {
619 	struct emac_softc *sc;
620 	struct mbuf *m, *m0;
621 	uint32_t fifo, reg;
622 
623 	sc = ifp->if_softc;
624 	if (ifp->if_drv_flags & IFF_DRV_OACTIVE)
625 		return;
626 	if (sc->emac_fifo_mask == (EMAC_TX_FIFO0 | EMAC_TX_FIFO1))
627 		return;
628 	if (sc->emac_link == 0)
629 		return;
630 	IFQ_DRV_DEQUEUE(&ifp->if_snd, m);
631 	if (m == NULL)
632 		return;
633 
634 	/* Select channel */
635 	if (sc->emac_fifo_mask & EMAC_TX_FIFO0)
636 		fifo = 1;
637 	else
638 		fifo = 0;
639 	sc->emac_fifo_mask |= (1 << fifo);
640 	if (sc->emac_fifo_mask == (EMAC_TX_FIFO0 | EMAC_TX_FIFO1))
641 		ifp->if_drv_flags |= IFF_DRV_OACTIVE;
642 	EMAC_WRITE_REG(sc, EMAC_TX_INS, fifo);
643 
644 	/*
645 	 * Emac controller wants 4 byte aligned TX buffers.
646 	 * We have to copy pretty much all the time.
647 	 */
648 	if (m->m_next != NULL || (mtod(m, uintptr_t) & 3) != 0) {
649 		m0 = m_defrag(m, M_NOWAIT);
650 		if (m0 == NULL) {
651 			m_freem(m);
652 			m = NULL;
653 			return;
654 		}
655 		m = m0;
656 	}
657 	/* Write data */
658 	bus_space_write_multi_4(sc->emac_tag, sc->emac_handle,
659 	    EMAC_TX_IO_DATA, mtod(m, uint32_t *),
660 	    roundup2(m->m_len, 4) / 4);
661 
662 	/* Send the data lengh. */
663 	reg = (fifo == 0) ? EMAC_TX_PL0 : EMAC_TX_PL1;
664 	EMAC_WRITE_REG(sc, reg, m->m_len);
665 
666 	/* Start translate from fifo to phy. */
667 	reg = (fifo == 0) ? EMAC_TX_CTL0 : EMAC_TX_CTL1;
668 	EMAC_WRITE_REG(sc, reg, EMAC_READ_REG(sc, reg) | 1);
669 
670 	/* Set timeout */
671 	sc->emac_watchdog_timer = 5;
672 
673 	/* Data have been sent to hardware, it is okay to free the mbuf now. */
674 	BPF_MTAP(ifp, m);
675 	m_freem(m);
676 }
677 
678 static void
679 emac_stop_locked(struct emac_softc *sc)
680 {
681 	struct ifnet *ifp;
682 	uint32_t reg_val;
683 
684 	EMAC_ASSERT_LOCKED(sc);
685 
686 	ifp = sc->emac_ifp;
687 	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
688 	sc->emac_link = 0;
689 
690 	/* Disable all interrupt and clear interrupt status */
691 	EMAC_WRITE_REG(sc, EMAC_INT_CTL, 0);
692 	reg_val = EMAC_READ_REG(sc, EMAC_INT_STA);
693 	EMAC_WRITE_REG(sc, EMAC_INT_STA, reg_val);
694 
695 	/* Disable RX/TX */
696 	reg_val = EMAC_READ_REG(sc, EMAC_CTL);
697 	reg_val &= ~(EMAC_CTL_RST | EMAC_CTL_TX_EN | EMAC_CTL_RX_EN);
698 	EMAC_WRITE_REG(sc, EMAC_CTL, reg_val);
699 
700 	callout_stop(&sc->emac_tick_ch);
701 }
702 
703 static void
704 emac_intr(void *arg)
705 {
706 	struct emac_softc *sc;
707 	struct ifnet *ifp;
708 	uint32_t reg_val;
709 
710 	sc = (struct emac_softc *)arg;
711 	EMAC_LOCK(sc);
712 
713 	/* Disable all interrupts */
714 	EMAC_WRITE_REG(sc, EMAC_INT_CTL, 0);
715 	/* Get EMAC interrupt status */
716 	reg_val = EMAC_READ_REG(sc, EMAC_INT_STA);
717 	/* Clear ISR status */
718 	EMAC_WRITE_REG(sc, EMAC_INT_STA, reg_val);
719 
720 	/* Received incoming packet */
721 	if (reg_val & EMAC_INT_STA_RX)
722 		emac_rxeof(sc, sc->emac_rx_process_limit);
723 
724 	/* Transmit Interrupt check */
725 	if (reg_val & EMAC_INT_STA_TX) {
726 		emac_txeof(sc, reg_val);
727 		ifp = sc->emac_ifp;
728 		if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))
729 			emac_start_locked(ifp);
730 	}
731 
732 	/* Re-enable interrupt mask */
733 	reg_val = EMAC_READ_REG(sc, EMAC_INT_CTL);
734 	reg_val |= EMAC_INT_EN;
735 	EMAC_WRITE_REG(sc, EMAC_INT_CTL, reg_val);
736 	EMAC_UNLOCK(sc);
737 }
738 
739 static int
740 emac_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
741 {
742 	struct emac_softc *sc;
743 	struct mii_data *mii;
744 	struct ifreq *ifr;
745 	int error = 0;
746 
747 	sc = ifp->if_softc;
748 	ifr = (struct ifreq *)data;
749 
750 	switch (command) {
751 	case SIOCSIFFLAGS:
752 		EMAC_LOCK(sc);
753 		if (ifp->if_flags & IFF_UP) {
754 			if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0) {
755 				if ((ifp->if_flags ^ sc->emac_if_flags) &
756 				    (IFF_PROMISC | IFF_ALLMULTI))
757 					emac_set_rx_mode(sc);
758 			} else
759 				emac_init_locked(sc);
760 		} else {
761 			if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
762 				emac_stop_locked(sc);
763 		}
764 		sc->emac_if_flags = ifp->if_flags;
765 		EMAC_UNLOCK(sc);
766 		break;
767 	case SIOCADDMULTI:
768 	case SIOCDELMULTI:
769 		EMAC_LOCK(sc);
770 		if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
771 			emac_set_rx_mode(sc);
772 		}
773 		EMAC_UNLOCK(sc);
774 		break;
775 	case SIOCGIFMEDIA:
776 	case SIOCSIFMEDIA:
777 		mii = device_get_softc(sc->emac_miibus);
778 		error = ifmedia_ioctl(ifp, ifr, &mii->mii_media, command);
779 		break;
780 	default:
781 		error = ether_ioctl(ifp, command, data);
782 		break;
783 	}
784 	return (error);
785 }
786 
787 static int
788 emac_probe(device_t dev)
789 {
790 
791 	if (!ofw_bus_status_okay(dev))
792 		return (ENXIO);
793 
794 	if (!ofw_bus_is_compatible(dev, "allwinner,sun4i-a10-emac"))
795 		return (ENXIO);
796 
797 	device_set_desc(dev, "A10/A20 EMAC ethernet controller");
798 	return (BUS_PROBE_DEFAULT);
799 }
800 
801 static int
802 emac_detach(device_t dev)
803 {
804 	struct emac_softc *sc;
805 
806 	sc = device_get_softc(dev);
807 	sc->emac_ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
808 	if (device_is_attached(dev)) {
809 		ether_ifdetach(sc->emac_ifp);
810 		EMAC_LOCK(sc);
811 		emac_stop_locked(sc);
812 		EMAC_UNLOCK(sc);
813 		callout_drain(&sc->emac_tick_ch);
814 	}
815 
816 	if (sc->emac_intrhand != NULL)
817 		bus_teardown_intr(sc->emac_dev, sc->emac_irq,
818 		    sc->emac_intrhand);
819 
820 	if (sc->emac_miibus != NULL) {
821 		device_delete_child(sc->emac_dev, sc->emac_miibus);
822 		bus_generic_detach(sc->emac_dev);
823 	}
824 
825 	if (sc->emac_clk != NULL)
826 		clk_disable(sc->emac_clk);
827 
828 	if (sc->emac_res != NULL)
829 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->emac_res);
830 
831 	if (sc->emac_irq != NULL)
832 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->emac_irq);
833 
834 	if (sc->emac_ifp != NULL)
835 		if_free(sc->emac_ifp);
836 
837 	if (mtx_initialized(&sc->emac_mtx))
838 		mtx_destroy(&sc->emac_mtx);
839 
840 	return (0);
841 }
842 
843 static int
844 emac_shutdown(device_t dev)
845 {
846 
847 	return (emac_suspend(dev));
848 }
849 
850 static int
851 emac_suspend(device_t dev)
852 {
853 	struct emac_softc *sc;
854 	struct ifnet *ifp;
855 
856 	sc = device_get_softc(dev);
857 
858 	EMAC_LOCK(sc);
859 	ifp = sc->emac_ifp;
860 	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) != 0)
861 		emac_stop_locked(sc);
862 	EMAC_UNLOCK(sc);
863 
864 	return (0);
865 }
866 
867 static int
868 emac_resume(device_t dev)
869 {
870 	struct emac_softc *sc;
871 	struct ifnet *ifp;
872 
873 	sc = device_get_softc(dev);
874 
875 	EMAC_LOCK(sc);
876 	ifp = sc->emac_ifp;
877 	if ((ifp->if_flags & IFF_UP) != 0) {
878 		ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
879 		emac_init_locked(sc);
880 	}
881 	EMAC_UNLOCK(sc);
882 
883 	return (0);
884 }
885 
886 static int
887 emac_attach(device_t dev)
888 {
889 	struct emac_softc *sc;
890 	struct ifnet *ifp;
891 	int error, rid;
892 	uint8_t eaddr[ETHER_ADDR_LEN];
893 
894 	sc = device_get_softc(dev);
895 	sc->emac_dev = dev;
896 
897 	error = 0;
898 	mtx_init(&sc->emac_mtx, device_get_nameunit(dev), MTX_NETWORK_LOCK,
899 	    MTX_DEF);
900 	callout_init_mtx(&sc->emac_tick_ch, &sc->emac_mtx, 0);
901 
902 	rid = 0;
903 	sc->emac_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
904 	    RF_ACTIVE);
905 	if (sc->emac_res == NULL) {
906 		device_printf(dev, "unable to map memory\n");
907 		error = ENXIO;
908 		goto fail;
909 	}
910 
911 	sc->emac_tag = rman_get_bustag(sc->emac_res);
912 	sc->emac_handle = rman_get_bushandle(sc->emac_res);
913 
914 	rid = 0;
915 	sc->emac_irq = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
916 	    RF_SHAREABLE | RF_ACTIVE);
917 	if (sc->emac_irq == NULL) {
918 		device_printf(dev, "cannot allocate IRQ resources.\n");
919 		error = ENXIO;
920 		goto fail;
921 	}
922 	/* Create device sysctl node. */
923 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
924 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
925 	    OID_AUTO, "process_limit", CTLTYPE_INT | CTLFLAG_RW,
926 	    &sc->emac_rx_process_limit, 0, sysctl_hw_emac_proc_limit, "I",
927 	    "max number of Rx events to process");
928 
929 	sc->emac_rx_process_limit = EMAC_PROC_DEFAULT;
930 	error = resource_int_value(device_get_name(dev), device_get_unit(dev),
931 	    "process_limit", &sc->emac_rx_process_limit);
932 	if (error == 0) {
933 		if (sc->emac_rx_process_limit < EMAC_PROC_MIN ||
934 		    sc->emac_rx_process_limit > EMAC_PROC_MAX) {
935 			device_printf(dev, "process_limit value out of range; "
936 			    "using default: %d\n", EMAC_PROC_DEFAULT);
937 			sc->emac_rx_process_limit = EMAC_PROC_DEFAULT;
938 		}
939 	}
940 	/* Setup EMAC */
941 	error = emac_sys_setup(sc);
942 	if (error != 0)
943 		goto fail;
944 
945 	emac_reset(sc);
946 
947 	ifp = sc->emac_ifp = if_alloc(IFT_ETHER);
948 	if (ifp == NULL) {
949 		device_printf(dev, "unable to allocate ifp\n");
950 		error = ENOSPC;
951 		goto fail;
952 	}
953 	ifp->if_softc = sc;
954 
955 	/* Setup MII */
956 	error = mii_attach(dev, &sc->emac_miibus, ifp, emac_ifmedia_upd,
957 	    emac_ifmedia_sts, BMSR_DEFCAPMASK, MII_PHY_ANY, MII_OFFSET_ANY, 0);
958 	if (error != 0) {
959 		device_printf(dev, "PHY probe failed\n");
960 		goto fail;
961 	}
962 
963 	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
964 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
965 	ifp->if_start = emac_start;
966 	ifp->if_ioctl = emac_ioctl;
967 	ifp->if_init = emac_init;
968 	IFQ_SET_MAXLEN(&ifp->if_snd, IFQ_MAXLEN);
969 
970 	/* Get MAC address */
971 	emac_get_hwaddr(sc, eaddr);
972 	ether_ifattach(ifp, eaddr);
973 
974 	/* VLAN capability setup. */
975 	ifp->if_capabilities |= IFCAP_VLAN_MTU;
976 	ifp->if_capenable = ifp->if_capabilities;
977 	/* Tell the upper layer we support VLAN over-sized frames. */
978 	ifp->if_hdrlen = sizeof(struct ether_vlan_header);
979 
980 	error = bus_setup_intr(dev, sc->emac_irq, INTR_TYPE_NET | INTR_MPSAFE,
981 	    NULL, emac_intr, sc, &sc->emac_intrhand);
982 	if (error != 0) {
983 		device_printf(dev, "could not set up interrupt handler.\n");
984 		ether_ifdetach(ifp);
985 		goto fail;
986 	}
987 
988 fail:
989 	if (error != 0)
990 		emac_detach(dev);
991 	return (error);
992 }
993 
994 static boolean_t
995 emac_miibus_iowait(struct emac_softc *sc)
996 {
997 	uint32_t timeout;
998 
999 	for (timeout = 100; timeout != 0; --timeout) {
1000 		DELAY(100);
1001 		if ((EMAC_READ_REG(sc, EMAC_MAC_MIND) & 0x1) == 0)
1002 			return (true);
1003 	}
1004 
1005 	return (false);
1006 }
1007 
1008 /*
1009  * The MII bus interface
1010  */
1011 static int
1012 emac_miibus_readreg(device_t dev, int phy, int reg)
1013 {
1014 	struct emac_softc *sc;
1015 	int rval;
1016 
1017 	sc = device_get_softc(dev);
1018 
1019 	/* Issue phy address and reg */
1020 	EMAC_WRITE_REG(sc, EMAC_MAC_MADR, (phy << 8) | reg);
1021 	/* Pull up the phy io line */
1022 	EMAC_WRITE_REG(sc, EMAC_MAC_MCMD, 0x1);
1023 	if (!emac_miibus_iowait(sc)) {
1024 		device_printf(dev, "timeout waiting for mii read\n");
1025 		return (0);
1026 	}
1027 	/* Push down the phy io line */
1028 	EMAC_WRITE_REG(sc, EMAC_MAC_MCMD, 0x0);
1029 	/* Read data */
1030 	rval = EMAC_READ_REG(sc, EMAC_MAC_MRDD);
1031 
1032 	return (rval);
1033 }
1034 
1035 static int
1036 emac_miibus_writereg(device_t dev, int phy, int reg, int data)
1037 {
1038 	struct emac_softc *sc;
1039 
1040 	sc = device_get_softc(dev);
1041 
1042 	/* Issue phy address and reg */
1043 	EMAC_WRITE_REG(sc, EMAC_MAC_MADR, (phy << 8) | reg);
1044 	/* Write data */
1045 	EMAC_WRITE_REG(sc, EMAC_MAC_MWTD, data);
1046 	/* Pull up the phy io line */
1047 	EMAC_WRITE_REG(sc, EMAC_MAC_MCMD, 0x1);
1048 	if (!emac_miibus_iowait(sc)) {
1049 		device_printf(dev, "timeout waiting for mii write\n");
1050 		return (0);
1051 	}
1052 	/* Push down the phy io line */
1053 	EMAC_WRITE_REG(sc, EMAC_MAC_MCMD, 0x0);
1054 
1055 	return (0);
1056 }
1057 
1058 static void
1059 emac_miibus_statchg(device_t dev)
1060 {
1061 	struct emac_softc *sc;
1062 	struct mii_data *mii;
1063 	struct ifnet *ifp;
1064 	uint32_t reg_val;
1065 
1066 	sc = device_get_softc(dev);
1067 
1068 	mii = device_get_softc(sc->emac_miibus);
1069 	ifp = sc->emac_ifp;
1070 	if (mii == NULL || ifp == NULL ||
1071 	    (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
1072 		return;
1073 
1074 	sc->emac_link = 0;
1075 	if ((mii->mii_media_status & (IFM_ACTIVE | IFM_AVALID)) ==
1076 	    (IFM_ACTIVE | IFM_AVALID)) {
1077 		switch (IFM_SUBTYPE(mii->mii_media_active)) {
1078 		case IFM_10_T:
1079 		case IFM_100_TX:
1080 			sc->emac_link = 1;
1081 			break;
1082 		default:
1083 			break;
1084 		}
1085 	}
1086 	/* Program MACs with resolved speed/duplex. */
1087 	if (sc->emac_link != 0) {
1088 		reg_val = EMAC_READ_REG(sc, EMAC_MAC_IPGT);
1089 		if ((IFM_OPTIONS(mii->mii_media_active) & IFM_FDX) != 0) {
1090 			reg_val &= ~EMAC_MAC_IPGT_HD;
1091 			reg_val |= EMAC_MAC_IPGT_FD;
1092 		} else {
1093 			reg_val &= ~EMAC_MAC_IPGT_FD;
1094 			reg_val |= EMAC_MAC_IPGT_HD;
1095 		}
1096 		EMAC_WRITE_REG(sc, EMAC_MAC_IPGT, reg_val);
1097 		/* Enable RX/TX */
1098 		reg_val = EMAC_READ_REG(sc, EMAC_CTL);
1099 		reg_val |= EMAC_CTL_RST | EMAC_CTL_TX_EN | EMAC_CTL_RX_EN;
1100 		EMAC_WRITE_REG(sc, EMAC_CTL, reg_val);
1101 	} else {
1102 		/* Disable RX/TX */
1103 		reg_val = EMAC_READ_REG(sc, EMAC_CTL);
1104 		reg_val &= ~(EMAC_CTL_RST | EMAC_CTL_TX_EN | EMAC_CTL_RX_EN);
1105 		EMAC_WRITE_REG(sc, EMAC_CTL, reg_val);
1106 	}
1107 }
1108 
1109 static int
1110 emac_ifmedia_upd(struct ifnet *ifp)
1111 {
1112 	struct emac_softc *sc;
1113 	struct mii_data *mii;
1114 	struct mii_softc *miisc;
1115 	int error;
1116 
1117 	sc = ifp->if_softc;
1118 	mii = device_get_softc(sc->emac_miibus);
1119 	EMAC_LOCK(sc);
1120 	LIST_FOREACH(miisc, &mii->mii_phys, mii_list)
1121 		PHY_RESET(miisc);
1122 	error = mii_mediachg(mii);
1123 	EMAC_UNLOCK(sc);
1124 
1125 	return (error);
1126 }
1127 
1128 static void
1129 emac_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr)
1130 {
1131 	struct emac_softc *sc;
1132 	struct mii_data *mii;
1133 
1134 	sc = ifp->if_softc;
1135 	mii = device_get_softc(sc->emac_miibus);
1136 
1137 	EMAC_LOCK(sc);
1138 	mii_pollstat(mii);
1139 	ifmr->ifm_active = mii->mii_media_active;
1140 	ifmr->ifm_status = mii->mii_media_status;
1141 	EMAC_UNLOCK(sc);
1142 }
1143 
1144 static device_method_t emac_methods[] = {
1145 	/* Device interface */
1146 	DEVMETHOD(device_probe,		emac_probe),
1147 	DEVMETHOD(device_attach,	emac_attach),
1148 	DEVMETHOD(device_detach,	emac_detach),
1149 	DEVMETHOD(device_shutdown,	emac_shutdown),
1150 	DEVMETHOD(device_suspend,	emac_suspend),
1151 	DEVMETHOD(device_resume,	emac_resume),
1152 
1153 	/* bus interface, for miibus */
1154 	DEVMETHOD(bus_print_child,	bus_generic_print_child),
1155 	DEVMETHOD(bus_driver_added,	bus_generic_driver_added),
1156 
1157 	/* MII interface */
1158 	DEVMETHOD(miibus_readreg,	emac_miibus_readreg),
1159 	DEVMETHOD(miibus_writereg,	emac_miibus_writereg),
1160 	DEVMETHOD(miibus_statchg,	emac_miibus_statchg),
1161 
1162 	DEVMETHOD_END
1163 };
1164 
1165 static driver_t emac_driver = {
1166 	"emac",
1167 	emac_methods,
1168 	sizeof(struct emac_softc)
1169 };
1170 
1171 static devclass_t emac_devclass;
1172 
1173 DRIVER_MODULE(emac, simplebus, emac_driver, emac_devclass, 0, 0);
1174 DRIVER_MODULE(miibus, emac, miibus_driver, miibus_devclass, 0, 0);
1175 MODULE_DEPEND(emac, miibus, 1, 1, 1);
1176 MODULE_DEPEND(emac, ether, 1, 1, 1);
1177 
1178 static int
1179 sysctl_int_range(SYSCTL_HANDLER_ARGS, int low, int high)
1180 {
1181 	int error, value;
1182 
1183 	if (arg1 == NULL)
1184 		return (EINVAL);
1185 	value = *(int *)arg1;
1186 	error = sysctl_handle_int(oidp, &value, 0, req);
1187 	if (error || req->newptr == NULL)
1188 		return (error);
1189 	if (value < low || value > high)
1190 		return (EINVAL);
1191 	*(int *)arg1 = value;
1192 
1193 	return (0);
1194 }
1195 
1196 static int
1197 sysctl_hw_emac_proc_limit(SYSCTL_HANDLER_ARGS)
1198 {
1199 
1200 	return (sysctl_int_range(oidp, arg1, arg2, req,
1201 	    EMAC_PROC_MIN, EMAC_PROC_MAX));
1202 }
1203