xref: /dflybsd-src/sys/dev/netif/em/if_em.c (revision 9ed293e071aa5626e1e68861be45f0002c7b0d8c)
1 /*
2  * Copyright (c) 2004 Joerg Sonnenberger <joerg@bec.de>.  All rights reserved.
3  *
4  * Copyright (c) 2001-2008, Intel Corporation
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 are met:
9  *
10  *  1. Redistributions of source code must retain the above copyright notice,
11  *     this list of conditions and the following disclaimer.
12  *
13  *  2. Redistributions in binary form must reproduce the above copyright
14  *     notice, this list of conditions and the following disclaimer in the
15  *     documentation and/or other materials provided with the distribution.
16  *
17  *  3. Neither the name of the Intel Corporation nor the names of its
18  *     contributors may be used to endorse or promote products derived from
19  *     this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
22  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
25  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  *
33  *
34  * Copyright (c) 2005 The DragonFly Project.  All rights reserved.
35  *
36  * This code is derived from software contributed to The DragonFly Project
37  * by Matthew Dillon <dillon@backplane.com>
38  *
39  * Redistribution and use in source and binary forms, with or without
40  * modification, are permitted provided that the following conditions
41  * are met:
42  *
43  * 1. Redistributions of source code must retain the above copyright
44  *    notice, this list of conditions and the following disclaimer.
45  * 2. Redistributions in binary form must reproduce the above copyright
46  *    notice, this list of conditions and the following disclaimer in
47  *    the documentation and/or other materials provided with the
48  *    distribution.
49  * 3. Neither the name of The DragonFly Project nor the names of its
50  *    contributors may be used to endorse or promote products derived
51  *    from this software without specific, prior written permission.
52  *
53  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
54  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
55  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
56  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
57  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
58  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
59  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
60  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
61  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
62  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
63  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64  * SUCH DAMAGE.
65  *
66  */
67 /*
68  * SERIALIZATION API RULES:
69  *
70  * - If the driver uses the same serializer for the interrupt as for the
71  *   ifnet, most of the serialization will be done automatically for the
72  *   driver.
73  *
74  * - ifmedia entry points will be serialized by the ifmedia code using the
75  *   ifnet serializer.
76  *
77  * - if_* entry points except for if_input will be serialized by the IF
78  *   and protocol layers.
79  *
80  * - The device driver must be sure to serialize access from timeout code
81  *   installed by the device driver.
82  *
83  * - The device driver typically holds the serializer at the time it wishes
84  *   to call if_input.
85  *
86  * - We must call lwkt_serialize_handler_enable() prior to enabling the
87  *   hardware interrupt and lwkt_serialize_handler_disable() after disabling
88  *   the hardware interrupt in order to avoid handler execution races from
89  *   scheduled interrupt threads.
90  *
91  *   NOTE!  Since callers into the device driver hold the ifnet serializer,
92  *   the device driver may be holding a serializer at the time it calls
93  *   if_input even if it is not serializer-aware.
94  */
95 
96 #include "opt_ifpoll.h"
97 
98 #include <sys/param.h>
99 #include <sys/bus.h>
100 #include <sys/endian.h>
101 #include <sys/interrupt.h>
102 #include <sys/kernel.h>
103 #include <sys/ktr.h>
104 #include <sys/malloc.h>
105 #include <sys/mbuf.h>
106 #include <sys/proc.h>
107 #include <sys/rman.h>
108 #include <sys/serialize.h>
109 #include <sys/socket.h>
110 #include <sys/sockio.h>
111 #include <sys/sysctl.h>
112 #include <sys/systm.h>
113 
114 #include <net/bpf.h>
115 #include <net/ethernet.h>
116 #include <net/if.h>
117 #include <net/if_arp.h>
118 #include <net/if_dl.h>
119 #include <net/if_media.h>
120 #include <net/if_poll.h>
121 #include <net/ifq_var.h>
122 #include <net/vlan/if_vlan_var.h>
123 #include <net/vlan/if_vlan_ether.h>
124 
125 #include <netinet/ip.h>
126 #include <netinet/tcp.h>
127 #include <netinet/udp.h>
128 
129 #include <bus/pci/pcivar.h>
130 #include <bus/pci/pcireg.h>
131 
132 #include <dev/netif/ig_hal/e1000_api.h>
133 #include <dev/netif/ig_hal/e1000_82571.h>
134 #include <dev/netif/em/if_em.h>
135 
136 #define EM_NAME	"Intel(R) PRO/1000 Network Connection "
137 #define EM_VER	" 7.2.4"
138 
139 #define _EM_DEVICE(id, ret)	\
140 	{ EM_VENDOR_ID, E1000_DEV_ID_##id, ret, EM_NAME #id EM_VER }
141 #define EM_EMX_DEVICE(id)	_EM_DEVICE(id, -100)
142 #define EM_DEVICE(id)		_EM_DEVICE(id, 0)
143 #define EM_DEVICE_NULL	{ 0, 0, 0, NULL }
144 
145 static const struct em_vendor_info em_vendor_info_array[] = {
146 	EM_DEVICE(82540EM),
147 	EM_DEVICE(82540EM_LOM),
148 	EM_DEVICE(82540EP),
149 	EM_DEVICE(82540EP_LOM),
150 	EM_DEVICE(82540EP_LP),
151 
152 	EM_DEVICE(82541EI),
153 	EM_DEVICE(82541ER),
154 	EM_DEVICE(82541ER_LOM),
155 	EM_DEVICE(82541EI_MOBILE),
156 	EM_DEVICE(82541GI),
157 	EM_DEVICE(82541GI_LF),
158 	EM_DEVICE(82541GI_MOBILE),
159 
160 	EM_DEVICE(82542),
161 
162 	EM_DEVICE(82543GC_FIBER),
163 	EM_DEVICE(82543GC_COPPER),
164 
165 	EM_DEVICE(82544EI_COPPER),
166 	EM_DEVICE(82544EI_FIBER),
167 	EM_DEVICE(82544GC_COPPER),
168 	EM_DEVICE(82544GC_LOM),
169 
170 	EM_DEVICE(82545EM_COPPER),
171 	EM_DEVICE(82545EM_FIBER),
172 	EM_DEVICE(82545GM_COPPER),
173 	EM_DEVICE(82545GM_FIBER),
174 	EM_DEVICE(82545GM_SERDES),
175 
176 	EM_DEVICE(82546EB_COPPER),
177 	EM_DEVICE(82546EB_FIBER),
178 	EM_DEVICE(82546EB_QUAD_COPPER),
179 	EM_DEVICE(82546GB_COPPER),
180 	EM_DEVICE(82546GB_FIBER),
181 	EM_DEVICE(82546GB_SERDES),
182 	EM_DEVICE(82546GB_PCIE),
183 	EM_DEVICE(82546GB_QUAD_COPPER),
184 	EM_DEVICE(82546GB_QUAD_COPPER_KSP3),
185 
186 	EM_DEVICE(82547EI),
187 	EM_DEVICE(82547EI_MOBILE),
188 	EM_DEVICE(82547GI),
189 
190 	EM_EMX_DEVICE(82571EB_COPPER),
191 	EM_EMX_DEVICE(82571EB_FIBER),
192 	EM_EMX_DEVICE(82571EB_SERDES),
193 	EM_EMX_DEVICE(82571EB_SERDES_DUAL),
194 	EM_EMX_DEVICE(82571EB_SERDES_QUAD),
195 	EM_EMX_DEVICE(82571EB_QUAD_COPPER),
196 	EM_EMX_DEVICE(82571EB_QUAD_COPPER_BP),
197 	EM_EMX_DEVICE(82571EB_QUAD_COPPER_LP),
198 	EM_EMX_DEVICE(82571EB_QUAD_FIBER),
199 	EM_EMX_DEVICE(82571PT_QUAD_COPPER),
200 
201 	EM_EMX_DEVICE(82572EI_COPPER),
202 	EM_EMX_DEVICE(82572EI_FIBER),
203 	EM_EMX_DEVICE(82572EI_SERDES),
204 	EM_EMX_DEVICE(82572EI),
205 
206 	EM_EMX_DEVICE(82573E),
207 	EM_EMX_DEVICE(82573E_IAMT),
208 	EM_EMX_DEVICE(82573L),
209 
210 	EM_DEVICE(82583V),
211 
212 	EM_EMX_DEVICE(80003ES2LAN_COPPER_SPT),
213 	EM_EMX_DEVICE(80003ES2LAN_SERDES_SPT),
214 	EM_EMX_DEVICE(80003ES2LAN_COPPER_DPT),
215 	EM_EMX_DEVICE(80003ES2LAN_SERDES_DPT),
216 
217 	EM_DEVICE(ICH8_IGP_M_AMT),
218 	EM_DEVICE(ICH8_IGP_AMT),
219 	EM_DEVICE(ICH8_IGP_C),
220 	EM_DEVICE(ICH8_IFE),
221 	EM_DEVICE(ICH8_IFE_GT),
222 	EM_DEVICE(ICH8_IFE_G),
223 	EM_DEVICE(ICH8_IGP_M),
224 	EM_DEVICE(ICH8_82567V_3),
225 
226 	EM_DEVICE(ICH9_IGP_M_AMT),
227 	EM_DEVICE(ICH9_IGP_AMT),
228 	EM_DEVICE(ICH9_IGP_C),
229 	EM_DEVICE(ICH9_IGP_M),
230 	EM_DEVICE(ICH9_IGP_M_V),
231 	EM_DEVICE(ICH9_IFE),
232 	EM_DEVICE(ICH9_IFE_GT),
233 	EM_DEVICE(ICH9_IFE_G),
234 	EM_DEVICE(ICH9_BM),
235 
236 	EM_EMX_DEVICE(82574L),
237 	EM_EMX_DEVICE(82574LA),
238 
239 	EM_DEVICE(ICH10_R_BM_LM),
240 	EM_DEVICE(ICH10_R_BM_LF),
241 	EM_DEVICE(ICH10_R_BM_V),
242 	EM_DEVICE(ICH10_D_BM_LM),
243 	EM_DEVICE(ICH10_D_BM_LF),
244 	EM_DEVICE(ICH10_D_BM_V),
245 
246 	EM_DEVICE(PCH_M_HV_LM),
247 	EM_DEVICE(PCH_M_HV_LC),
248 	EM_DEVICE(PCH_D_HV_DM),
249 	EM_DEVICE(PCH_D_HV_DC),
250 
251 	EM_DEVICE(PCH2_LV_LM),
252 	EM_DEVICE(PCH2_LV_V),
253 
254 	/* required last entry */
255 	EM_DEVICE_NULL
256 };
257 
258 static int	em_probe(device_t);
259 static int	em_attach(device_t);
260 static int	em_detach(device_t);
261 static int	em_shutdown(device_t);
262 static int	em_suspend(device_t);
263 static int	em_resume(device_t);
264 
265 static void	em_init(void *);
266 static void	em_stop(struct adapter *);
267 static int	em_ioctl(struct ifnet *, u_long, caddr_t, struct ucred *);
268 static void	em_start(struct ifnet *);
269 #ifdef IFPOLL_ENABLE
270 static void	em_npoll(struct ifnet *, struct ifpoll_info *);
271 static void	em_npoll_compat(struct ifnet *, void *, int);
272 #endif
273 static void	em_watchdog(struct ifnet *);
274 static void	em_media_status(struct ifnet *, struct ifmediareq *);
275 static int	em_media_change(struct ifnet *);
276 static void	em_timer(void *);
277 
278 static void	em_intr(void *);
279 static void	em_intr_mask(void *);
280 static void	em_intr_body(struct adapter *, boolean_t);
281 static void	em_rxeof(struct adapter *, int);
282 static void	em_txeof(struct adapter *);
283 static void	em_tx_collect(struct adapter *);
284 static void	em_tx_purge(struct adapter *);
285 static void	em_enable_intr(struct adapter *);
286 static void	em_disable_intr(struct adapter *);
287 
288 static int	em_dma_malloc(struct adapter *, bus_size_t,
289 		    struct em_dma_alloc *);
290 static void	em_dma_free(struct adapter *, struct em_dma_alloc *);
291 static void	em_init_tx_ring(struct adapter *);
292 static int	em_init_rx_ring(struct adapter *);
293 static int	em_create_tx_ring(struct adapter *);
294 static int	em_create_rx_ring(struct adapter *);
295 static void	em_destroy_tx_ring(struct adapter *, int);
296 static void	em_destroy_rx_ring(struct adapter *, int);
297 static int	em_newbuf(struct adapter *, int, int);
298 static int	em_encap(struct adapter *, struct mbuf **, int *, int *);
299 static void	em_rxcsum(struct adapter *, struct e1000_rx_desc *,
300 		    struct mbuf *);
301 static int	em_txcsum(struct adapter *, struct mbuf *,
302 		    uint32_t *, uint32_t *);
303 static int	em_tso_pullup(struct adapter *, struct mbuf **);
304 static int	em_tso_setup(struct adapter *, struct mbuf *,
305 		    uint32_t *, uint32_t *);
306 
307 static int	em_get_hw_info(struct adapter *);
308 static int 	em_is_valid_eaddr(const uint8_t *);
309 static int	em_alloc_pci_res(struct adapter *);
310 static void	em_free_pci_res(struct adapter *);
311 static int	em_reset(struct adapter *);
312 static void	em_setup_ifp(struct adapter *);
313 static void	em_init_tx_unit(struct adapter *);
314 static void	em_init_rx_unit(struct adapter *);
315 static void	em_update_stats(struct adapter *);
316 static void	em_set_promisc(struct adapter *);
317 static void	em_disable_promisc(struct adapter *);
318 static void	em_set_multi(struct adapter *);
319 static void	em_update_link_status(struct adapter *);
320 static void	em_smartspeed(struct adapter *);
321 static void	em_set_itr(struct adapter *, uint32_t);
322 static void	em_disable_aspm(struct adapter *);
323 
324 /* Hardware workarounds */
325 static int	em_82547_fifo_workaround(struct adapter *, int);
326 static void	em_82547_update_fifo_head(struct adapter *, int);
327 static int	em_82547_tx_fifo_reset(struct adapter *);
328 static void	em_82547_move_tail(void *);
329 static void	em_82547_move_tail_serialized(struct adapter *);
330 static uint32_t	em_82544_fill_desc(bus_addr_t, uint32_t, PDESC_ARRAY);
331 
332 static void	em_print_debug_info(struct adapter *);
333 static void	em_print_nvm_info(struct adapter *);
334 static void	em_print_hw_stats(struct adapter *);
335 
336 static int	em_sysctl_stats(SYSCTL_HANDLER_ARGS);
337 static int	em_sysctl_debug_info(SYSCTL_HANDLER_ARGS);
338 static int	em_sysctl_int_throttle(SYSCTL_HANDLER_ARGS);
339 static int	em_sysctl_int_tx_nsegs(SYSCTL_HANDLER_ARGS);
340 static void	em_add_sysctl(struct adapter *adapter);
341 
342 /* Management and WOL Support */
343 static void	em_get_mgmt(struct adapter *);
344 static void	em_rel_mgmt(struct adapter *);
345 static void	em_get_hw_control(struct adapter *);
346 static void	em_rel_hw_control(struct adapter *);
347 static void	em_enable_wol(device_t);
348 
349 static device_method_t em_methods[] = {
350 	/* Device interface */
351 	DEVMETHOD(device_probe,		em_probe),
352 	DEVMETHOD(device_attach,	em_attach),
353 	DEVMETHOD(device_detach,	em_detach),
354 	DEVMETHOD(device_shutdown,	em_shutdown),
355 	DEVMETHOD(device_suspend,	em_suspend),
356 	DEVMETHOD(device_resume,	em_resume),
357 	{ 0, 0 }
358 };
359 
360 static driver_t em_driver = {
361 	"em",
362 	em_methods,
363 	sizeof(struct adapter),
364 };
365 
366 static devclass_t em_devclass;
367 
368 DECLARE_DUMMY_MODULE(if_em);
369 MODULE_DEPEND(em, ig_hal, 1, 1, 1);
370 DRIVER_MODULE(if_em, pci, em_driver, em_devclass, NULL, NULL);
371 
372 /*
373  * Tunables
374  */
375 static int	em_int_throttle_ceil = EM_DEFAULT_ITR;
376 static int	em_rxd = EM_DEFAULT_RXD;
377 static int	em_txd = EM_DEFAULT_TXD;
378 static int	em_smart_pwr_down = 0;
379 
380 /* Controls whether promiscuous also shows bad packets */
381 static int	em_debug_sbp = FALSE;
382 
383 static int	em_82573_workaround = 1;
384 static int	em_msi_enable = 1;
385 
386 TUNABLE_INT("hw.em.int_throttle_ceil", &em_int_throttle_ceil);
387 TUNABLE_INT("hw.em.rxd", &em_rxd);
388 TUNABLE_INT("hw.em.txd", &em_txd);
389 TUNABLE_INT("hw.em.smart_pwr_down", &em_smart_pwr_down);
390 TUNABLE_INT("hw.em.sbp", &em_debug_sbp);
391 TUNABLE_INT("hw.em.82573_workaround", &em_82573_workaround);
392 TUNABLE_INT("hw.em.msi.enable", &em_msi_enable);
393 
394 /* Global used in WOL setup with multiport cards */
395 static int	em_global_quad_port_a = 0;
396 
397 /* Set this to one to display debug statistics */
398 static int	em_display_debug_stats = 0;
399 
400 #if !defined(KTR_IF_EM)
401 #define KTR_IF_EM	KTR_ALL
402 #endif
403 KTR_INFO_MASTER(if_em);
404 KTR_INFO(KTR_IF_EM, if_em, intr_beg, 0, "intr begin");
405 KTR_INFO(KTR_IF_EM, if_em, intr_end, 1, "intr end");
406 KTR_INFO(KTR_IF_EM, if_em, pkt_receive, 4, "rx packet");
407 KTR_INFO(KTR_IF_EM, if_em, pkt_txqueue, 5, "tx packet");
408 KTR_INFO(KTR_IF_EM, if_em, pkt_txclean, 6, "tx clean");
409 #define logif(name)	KTR_LOG(if_em_ ## name)
410 
411 static int
412 em_probe(device_t dev)
413 {
414 	const struct em_vendor_info *ent;
415 	uint16_t vid, did;
416 
417 	vid = pci_get_vendor(dev);
418 	did = pci_get_device(dev);
419 
420 	for (ent = em_vendor_info_array; ent->desc != NULL; ++ent) {
421 		if (vid == ent->vendor_id && did == ent->device_id) {
422 			device_set_desc(dev, ent->desc);
423 			device_set_async_attach(dev, TRUE);
424 			return (ent->ret);
425 		}
426 	}
427 	return (ENXIO);
428 }
429 
430 static int
431 em_attach(device_t dev)
432 {
433 	struct adapter *adapter = device_get_softc(dev);
434 	struct ifnet *ifp = &adapter->arpcom.ac_if;
435 	int tsize, rsize;
436 	int error = 0;
437 	uint16_t eeprom_data, device_id, apme_mask;
438 	driver_intr_t *intr_func;
439 
440 	adapter->dev = adapter->osdep.dev = dev;
441 
442 	callout_init_mp(&adapter->timer);
443 	callout_init_mp(&adapter->tx_fifo_timer);
444 
445 	/* Determine hardware and mac info */
446 	error = em_get_hw_info(adapter);
447 	if (error) {
448 		device_printf(dev, "Identify hardware failed\n");
449 		goto fail;
450 	}
451 
452 	/* Setup PCI resources */
453 	error = em_alloc_pci_res(adapter);
454 	if (error) {
455 		device_printf(dev, "Allocation of PCI resources failed\n");
456 		goto fail;
457 	}
458 
459 	/*
460 	 * For ICH8 and family we need to map the flash memory,
461 	 * and this must happen after the MAC is identified.
462 	 */
463 	if (adapter->hw.mac.type == e1000_ich8lan ||
464 	    adapter->hw.mac.type == e1000_ich9lan ||
465 	    adapter->hw.mac.type == e1000_ich10lan ||
466 	    adapter->hw.mac.type == e1000_pchlan ||
467 	    adapter->hw.mac.type == e1000_pch2lan) {
468 		adapter->flash_rid = EM_BAR_FLASH;
469 
470 		adapter->flash = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
471 					&adapter->flash_rid, RF_ACTIVE);
472 		if (adapter->flash == NULL) {
473 			device_printf(dev, "Mapping of Flash failed\n");
474 			error = ENXIO;
475 			goto fail;
476 		}
477 		adapter->osdep.flash_bus_space_tag =
478 		    rman_get_bustag(adapter->flash);
479 		adapter->osdep.flash_bus_space_handle =
480 		    rman_get_bushandle(adapter->flash);
481 
482 		/*
483 		 * This is used in the shared code
484 		 * XXX this goof is actually not used.
485 		 */
486 		adapter->hw.flash_address = (uint8_t *)adapter->flash;
487 	}
488 
489 	switch (adapter->hw.mac.type) {
490 	case e1000_82571:
491 	case e1000_82572:
492 		/*
493 		 * Pullup extra 4bytes into the first data segment, see:
494 		 * 82571/82572 specification update errata #7
495 		 *
496 		 * NOTE:
497 		 * 4bytes instead of 2bytes, which are mentioned in the
498 		 * errata, are pulled; mainly to keep rest of the data
499 		 * properly aligned.
500 		 */
501 		adapter->flags |= EM_FLAG_TSO_PULLEX;
502 		/* FALL THROUGH */
503 
504 	case e1000_82573:
505 	case e1000_82574:
506 	case e1000_80003es2lan:
507 		adapter->flags |= EM_FLAG_TSO;
508 		break;
509 
510 	default:
511 		break;
512 	}
513 
514 	/* Do Shared Code initialization */
515 	if (e1000_setup_init_funcs(&adapter->hw, TRUE)) {
516 		device_printf(dev, "Setup of Shared code failed\n");
517 		error = ENXIO;
518 		goto fail;
519 	}
520 
521 	e1000_get_bus_info(&adapter->hw);
522 
523 	/*
524 	 * Validate number of transmit and receive descriptors.  It
525 	 * must not exceed hardware maximum, and must be multiple
526 	 * of E1000_DBA_ALIGN.
527 	 */
528 	if ((em_txd * sizeof(struct e1000_tx_desc)) % EM_DBA_ALIGN != 0 ||
529 	    (adapter->hw.mac.type >= e1000_82544 && em_txd > EM_MAX_TXD) ||
530 	    (adapter->hw.mac.type < e1000_82544 && em_txd > EM_MAX_TXD_82543) ||
531 	    em_txd < EM_MIN_TXD) {
532 		device_printf(dev, "Using %d TX descriptors instead of %d!\n",
533 		    EM_DEFAULT_TXD, em_txd);
534 		adapter->num_tx_desc = EM_DEFAULT_TXD;
535 	} else {
536 		adapter->num_tx_desc = em_txd;
537 	}
538 	if ((em_rxd * sizeof(struct e1000_rx_desc)) % EM_DBA_ALIGN != 0 ||
539 	    (adapter->hw.mac.type >= e1000_82544 && em_rxd > EM_MAX_RXD) ||
540 	    (adapter->hw.mac.type < e1000_82544 && em_rxd > EM_MAX_RXD_82543) ||
541 	    em_rxd < EM_MIN_RXD) {
542 		device_printf(dev, "Using %d RX descriptors instead of %d!\n",
543 		    EM_DEFAULT_RXD, em_rxd);
544 		adapter->num_rx_desc = EM_DEFAULT_RXD;
545 	} else {
546 		adapter->num_rx_desc = em_rxd;
547 	}
548 
549 	adapter->hw.mac.autoneg = DO_AUTO_NEG;
550 	adapter->hw.phy.autoneg_wait_to_complete = FALSE;
551 	adapter->hw.phy.autoneg_advertised = AUTONEG_ADV_DEFAULT;
552 	adapter->rx_buffer_len = MCLBYTES;
553 
554 	/*
555 	 * Interrupt throttle rate
556 	 */
557 	if (em_int_throttle_ceil == 0) {
558 		adapter->int_throttle_ceil = 0;
559 	} else {
560 		int throttle = em_int_throttle_ceil;
561 
562 		if (throttle < 0)
563 			throttle = EM_DEFAULT_ITR;
564 
565 		/* Recalculate the tunable value to get the exact frequency. */
566 		throttle = 1000000000 / 256 / throttle;
567 
568 		/* Upper 16bits of ITR is reserved and should be zero */
569 		if (throttle & 0xffff0000)
570 			throttle = 1000000000 / 256 / EM_DEFAULT_ITR;
571 
572 		adapter->int_throttle_ceil = 1000000000 / 256 / throttle;
573 	}
574 
575 	e1000_init_script_state_82541(&adapter->hw, TRUE);
576 	e1000_set_tbi_compatibility_82543(&adapter->hw, TRUE);
577 
578 	/* Copper options */
579 	if (adapter->hw.phy.media_type == e1000_media_type_copper) {
580 		adapter->hw.phy.mdix = AUTO_ALL_MODES;
581 		adapter->hw.phy.disable_polarity_correction = FALSE;
582 		adapter->hw.phy.ms_type = EM_MASTER_SLAVE;
583 	}
584 
585 	/* Set the frame limits assuming standard ethernet sized frames. */
586 	adapter->max_frame_size = ETHERMTU + ETHER_HDR_LEN + ETHER_CRC_LEN;
587 	adapter->min_frame_size = ETH_ZLEN + ETHER_CRC_LEN;
588 
589 	/* This controls when hardware reports transmit completion status. */
590 	adapter->hw.mac.report_tx_early = 1;
591 
592 	/*
593 	 * Create top level busdma tag
594 	 */
595 	error = bus_dma_tag_create(NULL, 1, 0,
596 			BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR,
597 			NULL, NULL,
598 			BUS_SPACE_MAXSIZE_32BIT, 0, BUS_SPACE_MAXSIZE_32BIT,
599 			0, &adapter->parent_dtag);
600 	if (error) {
601 		device_printf(dev, "could not create top level DMA tag\n");
602 		goto fail;
603 	}
604 
605 	/*
606 	 * Allocate Transmit Descriptor ring
607 	 */
608 	tsize = roundup2(adapter->num_tx_desc * sizeof(struct e1000_tx_desc),
609 			 EM_DBA_ALIGN);
610 	error = em_dma_malloc(adapter, tsize, &adapter->txdma);
611 	if (error) {
612 		device_printf(dev, "Unable to allocate tx_desc memory\n");
613 		goto fail;
614 	}
615 	adapter->tx_desc_base = adapter->txdma.dma_vaddr;
616 
617 	/*
618 	 * Allocate Receive Descriptor ring
619 	 */
620 	rsize = roundup2(adapter->num_rx_desc * sizeof(struct e1000_rx_desc),
621 			 EM_DBA_ALIGN);
622 	error = em_dma_malloc(adapter, rsize, &adapter->rxdma);
623 	if (error) {
624 		device_printf(dev, "Unable to allocate rx_desc memory\n");
625 		goto fail;
626 	}
627 	adapter->rx_desc_base = adapter->rxdma.dma_vaddr;
628 
629 	/* Allocate multicast array memory. */
630 	adapter->mta = kmalloc(ETH_ADDR_LEN * MAX_NUM_MULTICAST_ADDRESSES,
631 	    M_DEVBUF, M_WAITOK);
632 
633 	/* Indicate SOL/IDER usage */
634 	if (e1000_check_reset_block(&adapter->hw)) {
635 		device_printf(dev,
636 		    "PHY reset is blocked due to SOL/IDER session.\n");
637 	}
638 
639 	/*
640 	 * Start from a known state, this is important in reading the
641 	 * nvm and mac from that.
642 	 */
643 	e1000_reset_hw(&adapter->hw);
644 
645 	/* Make sure we have a good EEPROM before we read from it */
646 	if (e1000_validate_nvm_checksum(&adapter->hw) < 0) {
647 		/*
648 		 * Some PCI-E parts fail the first check due to
649 		 * the link being in sleep state, call it again,
650 		 * if it fails a second time its a real issue.
651 		 */
652 		if (e1000_validate_nvm_checksum(&adapter->hw) < 0) {
653 			device_printf(dev,
654 			    "The EEPROM Checksum Is Not Valid\n");
655 			error = EIO;
656 			goto fail;
657 		}
658 	}
659 
660 	/* Copy the permanent MAC address out of the EEPROM */
661 	if (e1000_read_mac_addr(&adapter->hw) < 0) {
662 		device_printf(dev, "EEPROM read error while reading MAC"
663 		    " address\n");
664 		error = EIO;
665 		goto fail;
666 	}
667 	if (!em_is_valid_eaddr(adapter->hw.mac.addr)) {
668 		device_printf(dev, "Invalid MAC address\n");
669 		error = EIO;
670 		goto fail;
671 	}
672 
673 	/* Allocate transmit descriptors and buffers */
674 	error = em_create_tx_ring(adapter);
675 	if (error) {
676 		device_printf(dev, "Could not setup transmit structures\n");
677 		goto fail;
678 	}
679 
680 	/* Allocate receive descriptors and buffers */
681 	error = em_create_rx_ring(adapter);
682 	if (error) {
683 		device_printf(dev, "Could not setup receive structures\n");
684 		goto fail;
685 	}
686 
687 	/* Manually turn off all interrupts */
688 	E1000_WRITE_REG(&adapter->hw, E1000_IMC, 0xffffffff);
689 
690 	/* Determine if we have to control management hardware */
691 	if (e1000_enable_mng_pass_thru(&adapter->hw))
692 		adapter->flags |= EM_FLAG_HAS_MGMT;
693 
694 	/*
695 	 * Setup Wake-on-Lan
696 	 */
697 	apme_mask = EM_EEPROM_APME;
698 	eeprom_data = 0;
699 	switch (adapter->hw.mac.type) {
700 	case e1000_82542:
701 	case e1000_82543:
702 		break;
703 
704 	case e1000_82573:
705 	case e1000_82583:
706 		adapter->flags |= EM_FLAG_HAS_AMT;
707 		/* FALL THROUGH */
708 
709 	case e1000_82546:
710 	case e1000_82546_rev_3:
711 	case e1000_82571:
712 	case e1000_82572:
713 	case e1000_80003es2lan:
714 		if (adapter->hw.bus.func == 1) {
715 			e1000_read_nvm(&adapter->hw,
716 			    NVM_INIT_CONTROL3_PORT_B, 1, &eeprom_data);
717 		} else {
718 			e1000_read_nvm(&adapter->hw,
719 			    NVM_INIT_CONTROL3_PORT_A, 1, &eeprom_data);
720 		}
721 		break;
722 
723 	case e1000_ich8lan:
724 	case e1000_ich9lan:
725 	case e1000_ich10lan:
726 	case e1000_pchlan:
727 	case e1000_pch2lan:
728 		apme_mask = E1000_WUC_APME;
729 		adapter->flags |= EM_FLAG_HAS_AMT;
730 		eeprom_data = E1000_READ_REG(&adapter->hw, E1000_WUC);
731 		break;
732 
733 	default:
734 		e1000_read_nvm(&adapter->hw,
735 		    NVM_INIT_CONTROL3_PORT_A, 1, &eeprom_data);
736 		break;
737 	}
738 	if (eeprom_data & apme_mask)
739 		adapter->wol = E1000_WUFC_MAG | E1000_WUFC_MC;
740 
741 	/*
742          * We have the eeprom settings, now apply the special cases
743          * where the eeprom may be wrong or the board won't support
744          * wake on lan on a particular port
745 	 */
746 	device_id = pci_get_device(dev);
747         switch (device_id) {
748 	case E1000_DEV_ID_82546GB_PCIE:
749 		adapter->wol = 0;
750 		break;
751 
752 	case E1000_DEV_ID_82546EB_FIBER:
753 	case E1000_DEV_ID_82546GB_FIBER:
754 	case E1000_DEV_ID_82571EB_FIBER:
755 		/*
756 		 * Wake events only supported on port A for dual fiber
757 		 * regardless of eeprom setting
758 		 */
759 		if (E1000_READ_REG(&adapter->hw, E1000_STATUS) &
760 		    E1000_STATUS_FUNC_1)
761 			adapter->wol = 0;
762 		break;
763 
764 	case E1000_DEV_ID_82546GB_QUAD_COPPER_KSP3:
765 	case E1000_DEV_ID_82571EB_QUAD_COPPER:
766 	case E1000_DEV_ID_82571EB_QUAD_FIBER:
767 	case E1000_DEV_ID_82571EB_QUAD_COPPER_LP:
768                 /* if quad port adapter, disable WoL on all but port A */
769 		if (em_global_quad_port_a != 0)
770 			adapter->wol = 0;
771 		/* Reset for multiple quad port adapters */
772 		if (++em_global_quad_port_a == 4)
773 			em_global_quad_port_a = 0;
774                 break;
775 	}
776 
777 	/* XXX disable wol */
778 	adapter->wol = 0;
779 
780 	/* Setup OS specific network interface */
781 	em_setup_ifp(adapter);
782 
783 	/* Add sysctl tree, must after em_setup_ifp() */
784 	em_add_sysctl(adapter);
785 
786 #ifdef IFPOLL_ENABLE
787 	/* Polling setup */
788 	ifpoll_compat_setup(&adapter->npoll,
789 	    &adapter->sysctl_ctx, adapter->sysctl_tree, device_get_unit(dev),
790 	    ifp->if_serializer);
791 #endif
792 
793 	/* Reset the hardware */
794 	error = em_reset(adapter);
795 	if (error) {
796 		device_printf(dev, "Unable to reset the hardware\n");
797 		goto fail;
798 	}
799 
800 	/* Initialize statistics */
801 	em_update_stats(adapter);
802 
803 	adapter->hw.mac.get_link_status = 1;
804 	em_update_link_status(adapter);
805 
806 	/* Do we need workaround for 82544 PCI-X adapter? */
807 	if (adapter->hw.bus.type == e1000_bus_type_pcix &&
808 	    adapter->hw.mac.type == e1000_82544)
809 		adapter->pcix_82544 = TRUE;
810 	else
811 		adapter->pcix_82544 = FALSE;
812 
813 	if (adapter->pcix_82544) {
814 		/*
815 		 * 82544 on PCI-X may split one TX segment
816 		 * into two TX descs, so we double its number
817 		 * of spare TX desc here.
818 		 */
819 		adapter->spare_tx_desc = 2 * EM_TX_SPARE;
820 	} else {
821 		adapter->spare_tx_desc = EM_TX_SPARE;
822 	}
823 	if (adapter->flags & EM_FLAG_TSO)
824 		adapter->spare_tx_desc = EM_TX_SPARE_TSO;
825 	adapter->tx_wreg_nsegs = 8;
826 
827 	/*
828 	 * Keep following relationship between spare_tx_desc, oact_tx_desc
829 	 * and tx_int_nsegs:
830 	 * (spare_tx_desc + EM_TX_RESERVED) <=
831 	 * oact_tx_desc <= EM_TX_OACTIVE_MAX <= tx_int_nsegs
832 	 */
833 	adapter->oact_tx_desc = adapter->num_tx_desc / 8;
834 	if (adapter->oact_tx_desc > EM_TX_OACTIVE_MAX)
835 		adapter->oact_tx_desc = EM_TX_OACTIVE_MAX;
836 	if (adapter->oact_tx_desc < adapter->spare_tx_desc + EM_TX_RESERVED)
837 		adapter->oact_tx_desc = adapter->spare_tx_desc + EM_TX_RESERVED;
838 
839 	adapter->tx_int_nsegs = adapter->num_tx_desc / 16;
840 	if (adapter->tx_int_nsegs < adapter->oact_tx_desc)
841 		adapter->tx_int_nsegs = adapter->oact_tx_desc;
842 
843 	/* Non-AMT based hardware can now take control from firmware */
844 	if ((adapter->flags & (EM_FLAG_HAS_MGMT | EM_FLAG_HAS_AMT)) ==
845 	    EM_FLAG_HAS_MGMT && adapter->hw.mac.type >= e1000_82571)
846 		em_get_hw_control(adapter);
847 
848 	/*
849 	 * Missing Interrupt Following ICR read:
850 	 *
851 	 * 82571/82572 specification update errata #76
852 	 * 82573 specification update errata #31
853 	 * 82574 specification update errata #12
854 	 * 82583 specification update errata #4
855 	 */
856 	intr_func = em_intr;
857 	if ((adapter->flags & EM_FLAG_SHARED_INTR) &&
858 	    (adapter->hw.mac.type == e1000_82571 ||
859 	     adapter->hw.mac.type == e1000_82572 ||
860 	     adapter->hw.mac.type == e1000_82573 ||
861 	     adapter->hw.mac.type == e1000_82574 ||
862 	     adapter->hw.mac.type == e1000_82583))
863 		intr_func = em_intr_mask;
864 
865 	error = bus_setup_intr(dev, adapter->intr_res, INTR_MPSAFE,
866 			       intr_func, adapter, &adapter->intr_tag,
867 			       ifp->if_serializer);
868 	if (error) {
869 		device_printf(dev, "Failed to register interrupt handler");
870 		ether_ifdetach(&adapter->arpcom.ac_if);
871 		goto fail;
872 	}
873 
874 	ifp->if_cpuid = rman_get_cpuid(adapter->intr_res);
875 	KKASSERT(ifp->if_cpuid >= 0 && ifp->if_cpuid < ncpus);
876 	return (0);
877 fail:
878 	em_detach(dev);
879 	return (error);
880 }
881 
882 static int
883 em_detach(device_t dev)
884 {
885 	struct adapter *adapter = device_get_softc(dev);
886 
887 	if (device_is_attached(dev)) {
888 		struct ifnet *ifp = &adapter->arpcom.ac_if;
889 
890 		lwkt_serialize_enter(ifp->if_serializer);
891 
892 		em_stop(adapter);
893 
894 		e1000_phy_hw_reset(&adapter->hw);
895 
896 		em_rel_mgmt(adapter);
897 		em_rel_hw_control(adapter);
898 
899 		if (adapter->wol) {
900 			E1000_WRITE_REG(&adapter->hw, E1000_WUC,
901 					E1000_WUC_PME_EN);
902 			E1000_WRITE_REG(&adapter->hw, E1000_WUFC, adapter->wol);
903 			em_enable_wol(dev);
904 		}
905 
906 		bus_teardown_intr(dev, adapter->intr_res, adapter->intr_tag);
907 
908 		lwkt_serialize_exit(ifp->if_serializer);
909 
910 		ether_ifdetach(ifp);
911 	} else if (adapter->memory != NULL) {
912 		em_rel_hw_control(adapter);
913 	}
914 	bus_generic_detach(dev);
915 
916 	em_free_pci_res(adapter);
917 
918 	em_destroy_tx_ring(adapter, adapter->num_tx_desc);
919 	em_destroy_rx_ring(adapter, adapter->num_rx_desc);
920 
921 	/* Free Transmit Descriptor ring */
922 	if (adapter->tx_desc_base)
923 		em_dma_free(adapter, &adapter->txdma);
924 
925 	/* Free Receive Descriptor ring */
926 	if (adapter->rx_desc_base)
927 		em_dma_free(adapter, &adapter->rxdma);
928 
929 	/* Free top level busdma tag */
930 	if (adapter->parent_dtag != NULL)
931 		bus_dma_tag_destroy(adapter->parent_dtag);
932 
933 	/* Free sysctl tree */
934 	if (adapter->sysctl_tree != NULL)
935 		sysctl_ctx_free(&adapter->sysctl_ctx);
936 
937 	if (adapter->mta != NULL)
938 		kfree(adapter->mta, M_DEVBUF);
939 
940 	return (0);
941 }
942 
943 static int
944 em_shutdown(device_t dev)
945 {
946 	return em_suspend(dev);
947 }
948 
949 static int
950 em_suspend(device_t dev)
951 {
952 	struct adapter *adapter = device_get_softc(dev);
953 	struct ifnet *ifp = &adapter->arpcom.ac_if;
954 
955 	lwkt_serialize_enter(ifp->if_serializer);
956 
957 	em_stop(adapter);
958 
959 	em_rel_mgmt(adapter);
960 	em_rel_hw_control(adapter);
961 
962 	if (adapter->wol) {
963 		E1000_WRITE_REG(&adapter->hw, E1000_WUC, E1000_WUC_PME_EN);
964 		E1000_WRITE_REG(&adapter->hw, E1000_WUFC, adapter->wol);
965 		em_enable_wol(dev);
966 	}
967 
968 	lwkt_serialize_exit(ifp->if_serializer);
969 
970 	return bus_generic_suspend(dev);
971 }
972 
973 static int
974 em_resume(device_t dev)
975 {
976 	struct adapter *adapter = device_get_softc(dev);
977 	struct ifnet *ifp = &adapter->arpcom.ac_if;
978 
979 	lwkt_serialize_enter(ifp->if_serializer);
980 
981 	em_init(adapter);
982 	em_get_mgmt(adapter);
983 	if_devstart(ifp);
984 
985 	lwkt_serialize_exit(ifp->if_serializer);
986 
987 	return bus_generic_resume(dev);
988 }
989 
990 static void
991 em_start(struct ifnet *ifp)
992 {
993 	struct adapter *adapter = ifp->if_softc;
994 	struct mbuf *m_head;
995 	int idx = -1, nsegs = 0;
996 
997 	ASSERT_SERIALIZED(ifp->if_serializer);
998 
999 	if ((ifp->if_flags & IFF_RUNNING) == 0 || ifq_is_oactive(&ifp->if_snd))
1000 		return;
1001 
1002 	if (!adapter->link_active) {
1003 		ifq_purge(&ifp->if_snd);
1004 		return;
1005 	}
1006 
1007 	while (!ifq_is_empty(&ifp->if_snd)) {
1008 		/* Now do we at least have a minimal? */
1009 		if (EM_IS_OACTIVE(adapter)) {
1010 			em_tx_collect(adapter);
1011 			if (EM_IS_OACTIVE(adapter)) {
1012 				ifq_set_oactive(&ifp->if_snd);
1013 				adapter->no_tx_desc_avail1++;
1014 				break;
1015 			}
1016 		}
1017 
1018 		logif(pkt_txqueue);
1019 		m_head = ifq_dequeue(&ifp->if_snd, NULL);
1020 		if (m_head == NULL)
1021 			break;
1022 
1023 		if (em_encap(adapter, &m_head, &nsegs, &idx)) {
1024 			ifp->if_oerrors++;
1025 			em_tx_collect(adapter);
1026 			continue;
1027 		}
1028 
1029 		if (nsegs >= adapter->tx_wreg_nsegs && idx >= 0) {
1030 			E1000_WRITE_REG(&adapter->hw, E1000_TDT(0), idx);
1031 			nsegs = 0;
1032 			idx = -1;
1033 		}
1034 
1035 		/* Send a copy of the frame to the BPF listener */
1036 		ETHER_BPF_MTAP(ifp, m_head);
1037 
1038 		/* Set timeout in case hardware has problems transmitting. */
1039 		ifp->if_timer = EM_TX_TIMEOUT;
1040 	}
1041 	if (idx >= 0)
1042 		E1000_WRITE_REG(&adapter->hw, E1000_TDT(0), idx);
1043 }
1044 
1045 static int
1046 em_ioctl(struct ifnet *ifp, u_long command, caddr_t data, struct ucred *cr)
1047 {
1048 	struct adapter *adapter = ifp->if_softc;
1049 	struct ifreq *ifr = (struct ifreq *)data;
1050 	uint16_t eeprom_data = 0;
1051 	int max_frame_size, mask, reinit;
1052 	int error = 0;
1053 
1054 	ASSERT_SERIALIZED(ifp->if_serializer);
1055 
1056 	switch (command) {
1057 	case SIOCSIFMTU:
1058 		switch (adapter->hw.mac.type) {
1059 		case e1000_82573:
1060 			/*
1061 			 * 82573 only supports jumbo frames
1062 			 * if ASPM is disabled.
1063 			 */
1064 			e1000_read_nvm(&adapter->hw,
1065 			    NVM_INIT_3GIO_3, 1, &eeprom_data);
1066 			if (eeprom_data & NVM_WORD1A_ASPM_MASK) {
1067 				max_frame_size = ETHER_MAX_LEN;
1068 				break;
1069 			}
1070 			/* FALL THROUGH */
1071 
1072 		/* Limit Jumbo Frame size */
1073 		case e1000_82571:
1074 		case e1000_82572:
1075 		case e1000_ich9lan:
1076 		case e1000_ich10lan:
1077 		case e1000_pch2lan:
1078 		case e1000_82574:
1079 		case e1000_82583:
1080 		case e1000_80003es2lan:
1081 			max_frame_size = 9234;
1082 			break;
1083 
1084 		case e1000_pchlan:
1085 			max_frame_size = 4096;
1086 			break;
1087 
1088 		/* Adapters that do not support jumbo frames */
1089 		case e1000_82542:
1090 		case e1000_ich8lan:
1091 			max_frame_size = ETHER_MAX_LEN;
1092 			break;
1093 
1094 		default:
1095 			max_frame_size = MAX_JUMBO_FRAME_SIZE;
1096 			break;
1097 		}
1098 		if (ifr->ifr_mtu > max_frame_size - ETHER_HDR_LEN -
1099 		    ETHER_CRC_LEN) {
1100 			error = EINVAL;
1101 			break;
1102 		}
1103 
1104 		ifp->if_mtu = ifr->ifr_mtu;
1105 		adapter->max_frame_size =
1106 		    ifp->if_mtu + ETHER_HDR_LEN + ETHER_CRC_LEN;
1107 
1108 		if (ifp->if_flags & IFF_RUNNING)
1109 			em_init(adapter);
1110 		break;
1111 
1112 	case SIOCSIFFLAGS:
1113 		if (ifp->if_flags & IFF_UP) {
1114 			if ((ifp->if_flags & IFF_RUNNING)) {
1115 				if ((ifp->if_flags ^ adapter->if_flags) &
1116 				    (IFF_PROMISC | IFF_ALLMULTI)) {
1117 					em_disable_promisc(adapter);
1118 					em_set_promisc(adapter);
1119 				}
1120 			} else {
1121 				em_init(adapter);
1122 			}
1123 		} else if (ifp->if_flags & IFF_RUNNING) {
1124 			em_stop(adapter);
1125 		}
1126 		adapter->if_flags = ifp->if_flags;
1127 		break;
1128 
1129 	case SIOCADDMULTI:
1130 	case SIOCDELMULTI:
1131 		if (ifp->if_flags & IFF_RUNNING) {
1132 			em_disable_intr(adapter);
1133 			em_set_multi(adapter);
1134 			if (adapter->hw.mac.type == e1000_82542 &&
1135 			    adapter->hw.revision_id == E1000_REVISION_2)
1136 				em_init_rx_unit(adapter);
1137 #ifdef IFPOLL_ENABLE
1138 			if (!(ifp->if_flags & IFF_NPOLLING))
1139 #endif
1140 				em_enable_intr(adapter);
1141 		}
1142 		break;
1143 
1144 	case SIOCSIFMEDIA:
1145 		/* Check SOL/IDER usage */
1146 		if (e1000_check_reset_block(&adapter->hw)) {
1147 			device_printf(adapter->dev, "Media change is"
1148 			    " blocked due to SOL/IDER session.\n");
1149 			break;
1150 		}
1151 		/* FALL THROUGH */
1152 
1153 	case SIOCGIFMEDIA:
1154 		error = ifmedia_ioctl(ifp, ifr, &adapter->media, command);
1155 		break;
1156 
1157 	case SIOCSIFCAP:
1158 		reinit = 0;
1159 		mask = ifr->ifr_reqcap ^ ifp->if_capenable;
1160 		if (mask & IFCAP_RXCSUM) {
1161 			ifp->if_capenable ^= IFCAP_RXCSUM;
1162 			reinit = 1;
1163 		}
1164 		if (mask & IFCAP_TXCSUM) {
1165 			ifp->if_capenable ^= IFCAP_TXCSUM;
1166 			if (ifp->if_capenable & IFCAP_TXCSUM)
1167 				ifp->if_hwassist |= EM_CSUM_FEATURES;
1168 			else
1169 				ifp->if_hwassist &= ~EM_CSUM_FEATURES;
1170 		}
1171 		if (mask & IFCAP_TSO) {
1172 			ifp->if_capenable ^= IFCAP_TSO;
1173 			if (ifp->if_capenable & IFCAP_TSO)
1174 				ifp->if_hwassist |= CSUM_TSO;
1175 			else
1176 				ifp->if_hwassist &= ~CSUM_TSO;
1177 		}
1178 		if (mask & IFCAP_VLAN_HWTAGGING) {
1179 			ifp->if_capenable ^= IFCAP_VLAN_HWTAGGING;
1180 			reinit = 1;
1181 		}
1182 		if (reinit && (ifp->if_flags & IFF_RUNNING))
1183 			em_init(adapter);
1184 		break;
1185 
1186 	default:
1187 		error = ether_ioctl(ifp, command, data);
1188 		break;
1189 	}
1190 	return (error);
1191 }
1192 
1193 static void
1194 em_watchdog(struct ifnet *ifp)
1195 {
1196 	struct adapter *adapter = ifp->if_softc;
1197 
1198 	ASSERT_SERIALIZED(ifp->if_serializer);
1199 
1200 	/*
1201 	 * The timer is set to 5 every time start queues a packet.
1202 	 * Then txeof keeps resetting it as long as it cleans at
1203 	 * least one descriptor.
1204 	 * Finally, anytime all descriptors are clean the timer is
1205 	 * set to 0.
1206 	 */
1207 
1208 	if (E1000_READ_REG(&adapter->hw, E1000_TDT(0)) ==
1209 	    E1000_READ_REG(&adapter->hw, E1000_TDH(0))) {
1210 		/*
1211 		 * If we reach here, all TX jobs are completed and
1212 		 * the TX engine should have been idled for some time.
1213 		 * We don't need to call if_devstart() here.
1214 		 */
1215 		ifq_clr_oactive(&ifp->if_snd);
1216 		ifp->if_timer = 0;
1217 		return;
1218 	}
1219 
1220 	/*
1221 	 * If we are in this routine because of pause frames, then
1222 	 * don't reset the hardware.
1223 	 */
1224 	if (E1000_READ_REG(&adapter->hw, E1000_STATUS) &
1225 	    E1000_STATUS_TXOFF) {
1226 		ifp->if_timer = EM_TX_TIMEOUT;
1227 		return;
1228 	}
1229 
1230 	if (e1000_check_for_link(&adapter->hw) == 0)
1231 		if_printf(ifp, "watchdog timeout -- resetting\n");
1232 
1233 	ifp->if_oerrors++;
1234 	adapter->watchdog_events++;
1235 
1236 	em_init(adapter);
1237 
1238 	if (!ifq_is_empty(&ifp->if_snd))
1239 		if_devstart(ifp);
1240 }
1241 
1242 static void
1243 em_init(void *xsc)
1244 {
1245 	struct adapter *adapter = xsc;
1246 	struct ifnet *ifp = &adapter->arpcom.ac_if;
1247 	device_t dev = adapter->dev;
1248 	uint32_t pba;
1249 
1250 	ASSERT_SERIALIZED(ifp->if_serializer);
1251 
1252 	em_stop(adapter);
1253 
1254 	/*
1255 	 * Packet Buffer Allocation (PBA)
1256 	 * Writing PBA sets the receive portion of the buffer
1257 	 * the remainder is used for the transmit buffer.
1258 	 *
1259 	 * Devices before the 82547 had a Packet Buffer of 64K.
1260 	 *   Default allocation: PBA=48K for Rx, leaving 16K for Tx.
1261 	 * After the 82547 the buffer was reduced to 40K.
1262 	 *   Default allocation: PBA=30K for Rx, leaving 10K for Tx.
1263 	 *   Note: default does not leave enough room for Jumbo Frame >10k.
1264 	 */
1265 	switch (adapter->hw.mac.type) {
1266 	case e1000_82547:
1267 	case e1000_82547_rev_2: /* 82547: Total Packet Buffer is 40K */
1268 		if (adapter->max_frame_size > 8192)
1269 			pba = E1000_PBA_22K; /* 22K for Rx, 18K for Tx */
1270 		else
1271 			pba = E1000_PBA_30K; /* 30K for Rx, 10K for Tx */
1272 		adapter->tx_fifo_head = 0;
1273 		adapter->tx_head_addr = pba << EM_TX_HEAD_ADDR_SHIFT;
1274 		adapter->tx_fifo_size =
1275 		    (E1000_PBA_40K - pba) << EM_PBA_BYTES_SHIFT;
1276 		break;
1277 
1278 	/* Total Packet Buffer on these is 48K */
1279 	case e1000_82571:
1280 	case e1000_82572:
1281 	case e1000_80003es2lan:
1282 		pba = E1000_PBA_32K; /* 32K for Rx, 16K for Tx */
1283 		break;
1284 
1285 	case e1000_82573: /* 82573: Total Packet Buffer is 32K */
1286 		pba = E1000_PBA_12K; /* 12K for Rx, 20K for Tx */
1287 		break;
1288 
1289 	case e1000_82574:
1290 	case e1000_82583:
1291 		pba = E1000_PBA_20K; /* 20K for Rx, 20K for Tx */
1292 		break;
1293 
1294 	case e1000_ich8lan:
1295 		pba = E1000_PBA_8K;
1296 		break;
1297 
1298 	case e1000_ich9lan:
1299 	case e1000_ich10lan:
1300 #define E1000_PBA_10K	0x000A
1301 		pba = E1000_PBA_10K;
1302 		break;
1303 
1304 	case e1000_pchlan:
1305 	case e1000_pch2lan:
1306 		pba = E1000_PBA_26K;
1307 		break;
1308 
1309 	default:
1310 		/* Devices before 82547 had a Packet Buffer of 64K.   */
1311 		if (adapter->max_frame_size > 8192)
1312 			pba = E1000_PBA_40K; /* 40K for Rx, 24K for Tx */
1313 		else
1314 			pba = E1000_PBA_48K; /* 48K for Rx, 16K for Tx */
1315 	}
1316 	E1000_WRITE_REG(&adapter->hw, E1000_PBA, pba);
1317 
1318 	/* Get the latest mac address, User can use a LAA */
1319         bcopy(IF_LLADDR(ifp), adapter->hw.mac.addr, ETHER_ADDR_LEN);
1320 
1321 	/* Put the address into the Receive Address Array */
1322 	e1000_rar_set(&adapter->hw, adapter->hw.mac.addr, 0);
1323 
1324 	/*
1325 	 * With the 82571 adapter, RAR[0] may be overwritten
1326 	 * when the other port is reset, we make a duplicate
1327 	 * in RAR[14] for that eventuality, this assures
1328 	 * the interface continues to function.
1329 	 */
1330 	if (adapter->hw.mac.type == e1000_82571) {
1331 		e1000_set_laa_state_82571(&adapter->hw, TRUE);
1332 		e1000_rar_set(&adapter->hw, adapter->hw.mac.addr,
1333 		    E1000_RAR_ENTRIES - 1);
1334 	}
1335 
1336 	/* Reset the hardware */
1337 	if (em_reset(adapter)) {
1338 		device_printf(dev, "Unable to reset the hardware\n");
1339 		/* XXX em_stop()? */
1340 		return;
1341 	}
1342 	em_update_link_status(adapter);
1343 
1344 	/* Setup VLAN support, basic and offload if available */
1345 	E1000_WRITE_REG(&adapter->hw, E1000_VET, ETHERTYPE_VLAN);
1346 
1347 	if (ifp->if_capenable & IFCAP_VLAN_HWTAGGING) {
1348 		uint32_t ctrl;
1349 
1350 		ctrl = E1000_READ_REG(&adapter->hw, E1000_CTRL);
1351 		ctrl |= E1000_CTRL_VME;
1352 		E1000_WRITE_REG(&adapter->hw, E1000_CTRL, ctrl);
1353 	}
1354 
1355 	/* Configure for OS presence */
1356 	em_get_mgmt(adapter);
1357 
1358 	/* Prepare transmit descriptors and buffers */
1359 	em_init_tx_ring(adapter);
1360 	em_init_tx_unit(adapter);
1361 
1362 	/* Setup Multicast table */
1363 	em_set_multi(adapter);
1364 
1365 	/* Prepare receive descriptors and buffers */
1366 	if (em_init_rx_ring(adapter)) {
1367 		device_printf(dev, "Could not setup receive structures\n");
1368 		em_stop(adapter);
1369 		return;
1370 	}
1371 	em_init_rx_unit(adapter);
1372 
1373 	/* Don't lose promiscuous settings */
1374 	em_set_promisc(adapter);
1375 
1376 	ifp->if_flags |= IFF_RUNNING;
1377 	ifq_clr_oactive(&ifp->if_snd);
1378 
1379 	callout_reset(&adapter->timer, hz, em_timer, adapter);
1380 	e1000_clear_hw_cntrs_base_generic(&adapter->hw);
1381 
1382 	/* MSI/X configuration for 82574 */
1383 	if (adapter->hw.mac.type == e1000_82574) {
1384 		int tmp;
1385 
1386 		tmp = E1000_READ_REG(&adapter->hw, E1000_CTRL_EXT);
1387 		tmp |= E1000_CTRL_EXT_PBA_CLR;
1388 		E1000_WRITE_REG(&adapter->hw, E1000_CTRL_EXT, tmp);
1389 		/*
1390 		 * XXX MSIX
1391 		 * Set the IVAR - interrupt vector routing.
1392 		 * Each nibble represents a vector, high bit
1393 		 * is enable, other 3 bits are the MSIX table
1394 		 * entry, we map RXQ0 to 0, TXQ0 to 1, and
1395 		 * Link (other) to 2, hence the magic number.
1396 		 */
1397 		E1000_WRITE_REG(&adapter->hw, E1000_IVAR, 0x800A0908);
1398 	}
1399 
1400 #ifdef IFPOLL_ENABLE
1401 	/*
1402 	 * Only enable interrupts if we are not polling, make sure
1403 	 * they are off otherwise.
1404 	 */
1405 	if (ifp->if_flags & IFF_NPOLLING)
1406 		em_disable_intr(adapter);
1407 	else
1408 #endif /* IFPOLL_ENABLE */
1409 		em_enable_intr(adapter);
1410 
1411 	/* AMT based hardware can now take control from firmware */
1412 	if ((adapter->flags & (EM_FLAG_HAS_MGMT | EM_FLAG_HAS_AMT)) ==
1413 	    (EM_FLAG_HAS_MGMT | EM_FLAG_HAS_AMT) &&
1414 	    adapter->hw.mac.type >= e1000_82571)
1415 		em_get_hw_control(adapter);
1416 
1417 	/* Don't reset the phy next time init gets called */
1418 	adapter->hw.phy.reset_disable = TRUE;
1419 }
1420 
1421 #ifdef IFPOLL_ENABLE
1422 
1423 static void
1424 em_npoll_compat(struct ifnet *ifp, void *arg __unused, int count)
1425 {
1426 	struct adapter *adapter = ifp->if_softc;
1427 
1428 	ASSERT_SERIALIZED(ifp->if_serializer);
1429 
1430 	if (adapter->npoll.ifpc_stcount-- == 0) {
1431 		uint32_t reg_icr;
1432 
1433 		adapter->npoll.ifpc_stcount = adapter->npoll.ifpc_stfrac;
1434 
1435 		reg_icr = E1000_READ_REG(&adapter->hw, E1000_ICR);
1436 		if (reg_icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC)) {
1437 			callout_stop(&adapter->timer);
1438 			adapter->hw.mac.get_link_status = 1;
1439 			em_update_link_status(adapter);
1440 			callout_reset(&adapter->timer, hz, em_timer, adapter);
1441 		}
1442 	}
1443 
1444 	em_rxeof(adapter, count);
1445 	em_txeof(adapter);
1446 
1447 	if (!ifq_is_empty(&ifp->if_snd))
1448 		if_devstart(ifp);
1449 }
1450 
1451 static void
1452 em_npoll(struct ifnet *ifp, struct ifpoll_info *info)
1453 {
1454 	struct adapter *adapter = ifp->if_softc;
1455 
1456 	ASSERT_SERIALIZED(ifp->if_serializer);
1457 
1458 	if (info != NULL) {
1459 		int cpuid = adapter->npoll.ifpc_cpuid;
1460 
1461                 info->ifpi_rx[cpuid].poll_func = em_npoll_compat;
1462 		info->ifpi_rx[cpuid].arg = NULL;
1463 		info->ifpi_rx[cpuid].serializer = ifp->if_serializer;
1464 
1465 		if (ifp->if_flags & IFF_RUNNING)
1466 			em_disable_intr(adapter);
1467 		ifp->if_npoll_cpuid = cpuid;
1468 	} else {
1469 		if (ifp->if_flags & IFF_RUNNING)
1470 			em_enable_intr(adapter);
1471 		ifp->if_npoll_cpuid = -1;
1472 	}
1473 }
1474 
1475 #endif /* IFPOLL_ENABLE */
1476 
1477 static void
1478 em_intr(void *xsc)
1479 {
1480 	em_intr_body(xsc, TRUE);
1481 }
1482 
1483 static void
1484 em_intr_body(struct adapter *adapter, boolean_t chk_asserted)
1485 {
1486 	struct ifnet *ifp = &adapter->arpcom.ac_if;
1487 	uint32_t reg_icr;
1488 
1489 	logif(intr_beg);
1490 	ASSERT_SERIALIZED(ifp->if_serializer);
1491 
1492 	reg_icr = E1000_READ_REG(&adapter->hw, E1000_ICR);
1493 
1494 	if (chk_asserted &&
1495 	    ((adapter->hw.mac.type >= e1000_82571 &&
1496 	      (reg_icr & E1000_ICR_INT_ASSERTED) == 0) ||
1497 	     reg_icr == 0)) {
1498 		logif(intr_end);
1499 		return;
1500 	}
1501 
1502 	/*
1503 	 * XXX: some laptops trigger several spurious interrupts
1504 	 * on em(4) when in the resume cycle. The ICR register
1505 	 * reports all-ones value in this case. Processing such
1506 	 * interrupts would lead to a freeze. I don't know why.
1507 	 */
1508 	if (reg_icr == 0xffffffff) {
1509 		logif(intr_end);
1510 		return;
1511 	}
1512 
1513 	if (ifp->if_flags & IFF_RUNNING) {
1514 		if (reg_icr &
1515 		    (E1000_ICR_RXT0 | E1000_ICR_RXDMT0 | E1000_ICR_RXO))
1516 			em_rxeof(adapter, -1);
1517 		if (reg_icr & E1000_ICR_TXDW) {
1518 			em_txeof(adapter);
1519 			if (!ifq_is_empty(&ifp->if_snd))
1520 				if_devstart(ifp);
1521 		}
1522 	}
1523 
1524 	/* Link status change */
1525 	if (reg_icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC)) {
1526 		callout_stop(&adapter->timer);
1527 		adapter->hw.mac.get_link_status = 1;
1528 		em_update_link_status(adapter);
1529 
1530 		/* Deal with TX cruft when link lost */
1531 		em_tx_purge(adapter);
1532 
1533 		callout_reset(&adapter->timer, hz, em_timer, adapter);
1534 	}
1535 
1536 	if (reg_icr & E1000_ICR_RXO)
1537 		adapter->rx_overruns++;
1538 
1539 	logif(intr_end);
1540 }
1541 
1542 static void
1543 em_intr_mask(void *xsc)
1544 {
1545 	struct adapter *adapter = xsc;
1546 
1547 	E1000_WRITE_REG(&adapter->hw, E1000_IMC, 0xffffffff);
1548 	/*
1549 	 * NOTE:
1550 	 * ICR.INT_ASSERTED bit will never be set if IMS is 0,
1551 	 * so don't check it.
1552 	 */
1553 	em_intr_body(adapter, FALSE);
1554 	E1000_WRITE_REG(&adapter->hw, E1000_IMS, IMS_ENABLE_MASK);
1555 }
1556 
1557 static void
1558 em_media_status(struct ifnet *ifp, struct ifmediareq *ifmr)
1559 {
1560 	struct adapter *adapter = ifp->if_softc;
1561 	u_char fiber_type = IFM_1000_SX;
1562 
1563 	ASSERT_SERIALIZED(ifp->if_serializer);
1564 
1565 	em_update_link_status(adapter);
1566 
1567 	ifmr->ifm_status = IFM_AVALID;
1568 	ifmr->ifm_active = IFM_ETHER;
1569 
1570 	if (!adapter->link_active)
1571 		return;
1572 
1573 	ifmr->ifm_status |= IFM_ACTIVE;
1574 
1575 	if (adapter->hw.phy.media_type == e1000_media_type_fiber ||
1576 	    adapter->hw.phy.media_type == e1000_media_type_internal_serdes) {
1577 		if (adapter->hw.mac.type == e1000_82545)
1578 			fiber_type = IFM_1000_LX;
1579 		ifmr->ifm_active |= fiber_type | IFM_FDX;
1580 	} else {
1581 		switch (adapter->link_speed) {
1582 		case 10:
1583 			ifmr->ifm_active |= IFM_10_T;
1584 			break;
1585 		case 100:
1586 			ifmr->ifm_active |= IFM_100_TX;
1587 			break;
1588 
1589 		case 1000:
1590 			ifmr->ifm_active |= IFM_1000_T;
1591 			break;
1592 		}
1593 		if (adapter->link_duplex == FULL_DUPLEX)
1594 			ifmr->ifm_active |= IFM_FDX;
1595 		else
1596 			ifmr->ifm_active |= IFM_HDX;
1597 	}
1598 }
1599 
1600 static int
1601 em_media_change(struct ifnet *ifp)
1602 {
1603 	struct adapter *adapter = ifp->if_softc;
1604 	struct ifmedia *ifm = &adapter->media;
1605 
1606 	ASSERT_SERIALIZED(ifp->if_serializer);
1607 
1608 	if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER)
1609 		return (EINVAL);
1610 
1611 	switch (IFM_SUBTYPE(ifm->ifm_media)) {
1612 	case IFM_AUTO:
1613 		adapter->hw.mac.autoneg = DO_AUTO_NEG;
1614 		adapter->hw.phy.autoneg_advertised = AUTONEG_ADV_DEFAULT;
1615 		break;
1616 
1617 	case IFM_1000_LX:
1618 	case IFM_1000_SX:
1619 	case IFM_1000_T:
1620 		adapter->hw.mac.autoneg = DO_AUTO_NEG;
1621 		adapter->hw.phy.autoneg_advertised = ADVERTISE_1000_FULL;
1622 		break;
1623 
1624 	case IFM_100_TX:
1625 		adapter->hw.mac.autoneg = FALSE;
1626 		adapter->hw.phy.autoneg_advertised = 0;
1627 		if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
1628 			adapter->hw.mac.forced_speed_duplex = ADVERTISE_100_FULL;
1629 		else
1630 			adapter->hw.mac.forced_speed_duplex = ADVERTISE_100_HALF;
1631 		break;
1632 
1633 	case IFM_10_T:
1634 		adapter->hw.mac.autoneg = FALSE;
1635 		adapter->hw.phy.autoneg_advertised = 0;
1636 		if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
1637 			adapter->hw.mac.forced_speed_duplex = ADVERTISE_10_FULL;
1638 		else
1639 			adapter->hw.mac.forced_speed_duplex = ADVERTISE_10_HALF;
1640 		break;
1641 
1642 	default:
1643 		if_printf(ifp, "Unsupported media type\n");
1644 		break;
1645 	}
1646 
1647 	/*
1648 	 * As the speed/duplex settings my have changed we need to
1649 	 * reset the PHY.
1650 	 */
1651 	adapter->hw.phy.reset_disable = FALSE;
1652 
1653 	em_init(adapter);
1654 
1655 	return (0);
1656 }
1657 
1658 static int
1659 em_encap(struct adapter *adapter, struct mbuf **m_headp,
1660     int *segs_used, int *idx)
1661 {
1662 	bus_dma_segment_t segs[EM_MAX_SCATTER];
1663 	bus_dmamap_t map;
1664 	struct em_buffer *tx_buffer, *tx_buffer_mapped;
1665 	struct e1000_tx_desc *ctxd = NULL;
1666 	struct mbuf *m_head = *m_headp;
1667 	uint32_t txd_upper, txd_lower, txd_used, cmd = 0;
1668 	int maxsegs, nsegs, i, j, first, last = 0, error;
1669 
1670 	if (m_head->m_pkthdr.csum_flags & CSUM_TSO) {
1671 		error = em_tso_pullup(adapter, m_headp);
1672 		if (error)
1673 			return error;
1674 		m_head = *m_headp;
1675 	}
1676 
1677 	txd_upper = txd_lower = 0;
1678 	txd_used = 0;
1679 
1680 	/*
1681 	 * Capture the first descriptor index, this descriptor
1682 	 * will have the index of the EOP which is the only one
1683 	 * that now gets a DONE bit writeback.
1684 	 */
1685 	first = adapter->next_avail_tx_desc;
1686 	tx_buffer = &adapter->tx_buffer_area[first];
1687 	tx_buffer_mapped = tx_buffer;
1688 	map = tx_buffer->map;
1689 
1690 	maxsegs = adapter->num_tx_desc_avail - EM_TX_RESERVED;
1691 	KASSERT(maxsegs >= adapter->spare_tx_desc,
1692 		("not enough spare TX desc"));
1693 	if (adapter->pcix_82544) {
1694 		/* Half it; see the comment in em_attach() */
1695 		maxsegs >>= 1;
1696 	}
1697 	if (maxsegs > EM_MAX_SCATTER)
1698 		maxsegs = EM_MAX_SCATTER;
1699 
1700 	error = bus_dmamap_load_mbuf_defrag(adapter->txtag, map, m_headp,
1701 			segs, maxsegs, &nsegs, BUS_DMA_NOWAIT);
1702 	if (error) {
1703 		if (error == ENOBUFS)
1704 			adapter->mbuf_alloc_failed++;
1705 		else
1706 			adapter->no_tx_dma_setup++;
1707 
1708 		m_freem(*m_headp);
1709 		*m_headp = NULL;
1710 		return error;
1711 	}
1712         bus_dmamap_sync(adapter->txtag, map, BUS_DMASYNC_PREWRITE);
1713 
1714 	m_head = *m_headp;
1715 	adapter->tx_nsegs += nsegs;
1716 	*segs_used += nsegs;
1717 
1718 	if (m_head->m_pkthdr.csum_flags & CSUM_TSO) {
1719 		/* TSO will consume one TX desc */
1720 		i = em_tso_setup(adapter, m_head, &txd_upper, &txd_lower);
1721 		adapter->tx_nsegs += i;
1722 		*segs_used += i;
1723 	} else if (m_head->m_pkthdr.csum_flags & EM_CSUM_FEATURES) {
1724 		/* TX csum offloading will consume one TX desc */
1725 		i = em_txcsum(adapter, m_head, &txd_upper, &txd_lower);
1726 		adapter->tx_nsegs += i;
1727 		*segs_used += i;
1728 	}
1729 	i = adapter->next_avail_tx_desc;
1730 
1731 	/* Set up our transmit descriptors */
1732 	for (j = 0; j < nsegs; j++) {
1733 		/* If adapter is 82544 and on PCIX bus */
1734 		if(adapter->pcix_82544) {
1735 			DESC_ARRAY desc_array;
1736 			uint32_t array_elements, counter;
1737 
1738 			/*
1739 			 * Check the Address and Length combination and
1740 			 * split the data accordingly
1741 			 */
1742 			array_elements = em_82544_fill_desc(segs[j].ds_addr,
1743 						segs[j].ds_len, &desc_array);
1744 			for (counter = 0; counter < array_elements; counter++) {
1745 				KKASSERT(txd_used < adapter->num_tx_desc_avail);
1746 
1747 				tx_buffer = &adapter->tx_buffer_area[i];
1748 				ctxd = &adapter->tx_desc_base[i];
1749 
1750 				ctxd->buffer_addr = htole64(
1751 				    desc_array.descriptor[counter].address);
1752 				ctxd->lower.data = htole32(
1753 				    E1000_TXD_CMD_IFCS | txd_lower |
1754 				    desc_array.descriptor[counter].length);
1755 				ctxd->upper.data = htole32(txd_upper);
1756 
1757 				last = i;
1758 				if (++i == adapter->num_tx_desc)
1759 					i = 0;
1760 
1761 				txd_used++;
1762                         }
1763 		} else {
1764 			tx_buffer = &adapter->tx_buffer_area[i];
1765 			ctxd = &adapter->tx_desc_base[i];
1766 
1767 			ctxd->buffer_addr = htole64(segs[j].ds_addr);
1768 			ctxd->lower.data = htole32(E1000_TXD_CMD_IFCS |
1769 						   txd_lower | segs[j].ds_len);
1770 			ctxd->upper.data = htole32(txd_upper);
1771 
1772 			last = i;
1773 			if (++i == adapter->num_tx_desc)
1774 				i = 0;
1775 		}
1776 	}
1777 
1778 	adapter->next_avail_tx_desc = i;
1779 	if (adapter->pcix_82544) {
1780 		KKASSERT(adapter->num_tx_desc_avail > txd_used);
1781 		adapter->num_tx_desc_avail -= txd_used;
1782 	} else {
1783 		KKASSERT(adapter->num_tx_desc_avail > nsegs);
1784 		adapter->num_tx_desc_avail -= nsegs;
1785 	}
1786 
1787         /* Handle VLAN tag */
1788 	if (m_head->m_flags & M_VLANTAG) {
1789 		/* Set the vlan id. */
1790 		ctxd->upper.fields.special =
1791 		    htole16(m_head->m_pkthdr.ether_vlantag);
1792 
1793 		/* Tell hardware to add tag */
1794 		ctxd->lower.data |= htole32(E1000_TXD_CMD_VLE);
1795 	}
1796 
1797 	tx_buffer->m_head = m_head;
1798 	tx_buffer_mapped->map = tx_buffer->map;
1799 	tx_buffer->map = map;
1800 
1801 	if (adapter->tx_nsegs >= adapter->tx_int_nsegs) {
1802 		adapter->tx_nsegs = 0;
1803 
1804 		/*
1805 		 * Report Status (RS) is turned on
1806 		 * every tx_int_nsegs descriptors.
1807 		 */
1808 		cmd = E1000_TXD_CMD_RS;
1809 
1810 		/*
1811 		 * Keep track of the descriptor, which will
1812 		 * be written back by hardware.
1813 		 */
1814 		adapter->tx_dd[adapter->tx_dd_tail] = last;
1815 		EM_INC_TXDD_IDX(adapter->tx_dd_tail);
1816 		KKASSERT(adapter->tx_dd_tail != adapter->tx_dd_head);
1817 	}
1818 
1819 	/*
1820 	 * Last Descriptor of Packet needs End Of Packet (EOP)
1821 	 */
1822 	ctxd->lower.data |= htole32(E1000_TXD_CMD_EOP | cmd);
1823 
1824 	if (adapter->hw.mac.type == e1000_82547) {
1825 		/*
1826 		 * Advance the Transmit Descriptor Tail (TDT), this tells the
1827 		 * E1000 that this frame is available to transmit.
1828 		 */
1829 		if (adapter->link_duplex == HALF_DUPLEX) {
1830 			em_82547_move_tail_serialized(adapter);
1831 		} else {
1832 			E1000_WRITE_REG(&adapter->hw, E1000_TDT(0), i);
1833 			em_82547_update_fifo_head(adapter,
1834 			    m_head->m_pkthdr.len);
1835 		}
1836 	} else {
1837 		/*
1838 		 * Defer TDT updating, until enough descriptors are setup
1839 		 */
1840 		*idx = i;
1841 	}
1842 	return (0);
1843 }
1844 
1845 /*
1846  * 82547 workaround to avoid controller hang in half-duplex environment.
1847  * The workaround is to avoid queuing a large packet that would span
1848  * the internal Tx FIFO ring boundary.  We need to reset the FIFO pointers
1849  * in this case.  We do that only when FIFO is quiescent.
1850  */
1851 static void
1852 em_82547_move_tail_serialized(struct adapter *adapter)
1853 {
1854 	struct e1000_tx_desc *tx_desc;
1855 	uint16_t hw_tdt, sw_tdt, length = 0;
1856 	bool eop = 0;
1857 
1858 	ASSERT_SERIALIZED(adapter->arpcom.ac_if.if_serializer);
1859 
1860 	hw_tdt = E1000_READ_REG(&adapter->hw, E1000_TDT(0));
1861 	sw_tdt = adapter->next_avail_tx_desc;
1862 
1863 	while (hw_tdt != sw_tdt) {
1864 		tx_desc = &adapter->tx_desc_base[hw_tdt];
1865 		length += tx_desc->lower.flags.length;
1866 		eop = tx_desc->lower.data & E1000_TXD_CMD_EOP;
1867 		if (++hw_tdt == adapter->num_tx_desc)
1868 			hw_tdt = 0;
1869 
1870 		if (eop) {
1871 			if (em_82547_fifo_workaround(adapter, length)) {
1872 				adapter->tx_fifo_wrk_cnt++;
1873 				callout_reset(&adapter->tx_fifo_timer, 1,
1874 					em_82547_move_tail, adapter);
1875 				break;
1876 			}
1877 			E1000_WRITE_REG(&adapter->hw, E1000_TDT(0), hw_tdt);
1878 			em_82547_update_fifo_head(adapter, length);
1879 			length = 0;
1880 		}
1881 	}
1882 }
1883 
1884 static void
1885 em_82547_move_tail(void *xsc)
1886 {
1887 	struct adapter *adapter = xsc;
1888 	struct ifnet *ifp = &adapter->arpcom.ac_if;
1889 
1890 	lwkt_serialize_enter(ifp->if_serializer);
1891 	em_82547_move_tail_serialized(adapter);
1892 	lwkt_serialize_exit(ifp->if_serializer);
1893 }
1894 
1895 static int
1896 em_82547_fifo_workaround(struct adapter *adapter, int len)
1897 {
1898 	int fifo_space, fifo_pkt_len;
1899 
1900 	fifo_pkt_len = roundup2(len + EM_FIFO_HDR, EM_FIFO_HDR);
1901 
1902 	if (adapter->link_duplex == HALF_DUPLEX) {
1903 		fifo_space = adapter->tx_fifo_size - adapter->tx_fifo_head;
1904 
1905 		if (fifo_pkt_len >= (EM_82547_PKT_THRESH + fifo_space)) {
1906 			if (em_82547_tx_fifo_reset(adapter))
1907 				return (0);
1908 			else
1909 				return (1);
1910 		}
1911 	}
1912 	return (0);
1913 }
1914 
1915 static void
1916 em_82547_update_fifo_head(struct adapter *adapter, int len)
1917 {
1918 	int fifo_pkt_len = roundup2(len + EM_FIFO_HDR, EM_FIFO_HDR);
1919 
1920 	/* tx_fifo_head is always 16 byte aligned */
1921 	adapter->tx_fifo_head += fifo_pkt_len;
1922 	if (adapter->tx_fifo_head >= adapter->tx_fifo_size)
1923 		adapter->tx_fifo_head -= adapter->tx_fifo_size;
1924 }
1925 
1926 static int
1927 em_82547_tx_fifo_reset(struct adapter *adapter)
1928 {
1929 	uint32_t tctl;
1930 
1931 	if ((E1000_READ_REG(&adapter->hw, E1000_TDT(0)) ==
1932 	     E1000_READ_REG(&adapter->hw, E1000_TDH(0))) &&
1933 	    (E1000_READ_REG(&adapter->hw, E1000_TDFT) ==
1934 	     E1000_READ_REG(&adapter->hw, E1000_TDFH)) &&
1935 	    (E1000_READ_REG(&adapter->hw, E1000_TDFTS) ==
1936 	     E1000_READ_REG(&adapter->hw, E1000_TDFHS)) &&
1937 	    (E1000_READ_REG(&adapter->hw, E1000_TDFPC) == 0)) {
1938 		/* Disable TX unit */
1939 		tctl = E1000_READ_REG(&adapter->hw, E1000_TCTL);
1940 		E1000_WRITE_REG(&adapter->hw, E1000_TCTL,
1941 		    tctl & ~E1000_TCTL_EN);
1942 
1943 		/* Reset FIFO pointers */
1944 		E1000_WRITE_REG(&adapter->hw, E1000_TDFT,
1945 		    adapter->tx_head_addr);
1946 		E1000_WRITE_REG(&adapter->hw, E1000_TDFH,
1947 		    adapter->tx_head_addr);
1948 		E1000_WRITE_REG(&adapter->hw, E1000_TDFTS,
1949 		    adapter->tx_head_addr);
1950 		E1000_WRITE_REG(&adapter->hw, E1000_TDFHS,
1951 		    adapter->tx_head_addr);
1952 
1953 		/* Re-enable TX unit */
1954 		E1000_WRITE_REG(&adapter->hw, E1000_TCTL, tctl);
1955 		E1000_WRITE_FLUSH(&adapter->hw);
1956 
1957 		adapter->tx_fifo_head = 0;
1958 		adapter->tx_fifo_reset_cnt++;
1959 
1960 		return (TRUE);
1961 	} else {
1962 		return (FALSE);
1963 	}
1964 }
1965 
1966 static void
1967 em_set_promisc(struct adapter *adapter)
1968 {
1969 	struct ifnet *ifp = &adapter->arpcom.ac_if;
1970 	uint32_t reg_rctl;
1971 
1972 	reg_rctl = E1000_READ_REG(&adapter->hw, E1000_RCTL);
1973 
1974 	if (ifp->if_flags & IFF_PROMISC) {
1975 		reg_rctl |= (E1000_RCTL_UPE | E1000_RCTL_MPE);
1976 		/* Turn this on if you want to see bad packets */
1977 		if (em_debug_sbp)
1978 			reg_rctl |= E1000_RCTL_SBP;
1979 		E1000_WRITE_REG(&adapter->hw, E1000_RCTL, reg_rctl);
1980 	} else if (ifp->if_flags & IFF_ALLMULTI) {
1981 		reg_rctl |= E1000_RCTL_MPE;
1982 		reg_rctl &= ~E1000_RCTL_UPE;
1983 		E1000_WRITE_REG(&adapter->hw, E1000_RCTL, reg_rctl);
1984 	}
1985 }
1986 
1987 static void
1988 em_disable_promisc(struct adapter *adapter)
1989 {
1990 	uint32_t reg_rctl;
1991 
1992 	reg_rctl = E1000_READ_REG(&adapter->hw, E1000_RCTL);
1993 
1994 	reg_rctl &= ~E1000_RCTL_UPE;
1995 	reg_rctl &= ~E1000_RCTL_MPE;
1996 	reg_rctl &= ~E1000_RCTL_SBP;
1997 	E1000_WRITE_REG(&adapter->hw, E1000_RCTL, reg_rctl);
1998 }
1999 
2000 static void
2001 em_set_multi(struct adapter *adapter)
2002 {
2003 	struct ifnet *ifp = &adapter->arpcom.ac_if;
2004 	struct ifmultiaddr *ifma;
2005 	uint32_t reg_rctl = 0;
2006 	uint8_t *mta;
2007 	int mcnt = 0;
2008 
2009 	mta = adapter->mta;
2010 	bzero(mta, ETH_ADDR_LEN * MAX_NUM_MULTICAST_ADDRESSES);
2011 
2012 	if (adapter->hw.mac.type == e1000_82542 &&
2013 	    adapter->hw.revision_id == E1000_REVISION_2) {
2014 		reg_rctl = E1000_READ_REG(&adapter->hw, E1000_RCTL);
2015 		if (adapter->hw.bus.pci_cmd_word & CMD_MEM_WRT_INVALIDATE)
2016 			e1000_pci_clear_mwi(&adapter->hw);
2017 		reg_rctl |= E1000_RCTL_RST;
2018 		E1000_WRITE_REG(&adapter->hw, E1000_RCTL, reg_rctl);
2019 		msec_delay(5);
2020 	}
2021 
2022 	TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
2023 		if (ifma->ifma_addr->sa_family != AF_LINK)
2024 			continue;
2025 
2026 		if (mcnt == MAX_NUM_MULTICAST_ADDRESSES)
2027 			break;
2028 
2029 		bcopy(LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
2030 		    &mta[mcnt * ETHER_ADDR_LEN], ETHER_ADDR_LEN);
2031 		mcnt++;
2032 	}
2033 
2034 	if (mcnt >= MAX_NUM_MULTICAST_ADDRESSES) {
2035 		reg_rctl = E1000_READ_REG(&adapter->hw, E1000_RCTL);
2036 		reg_rctl |= E1000_RCTL_MPE;
2037 		E1000_WRITE_REG(&adapter->hw, E1000_RCTL, reg_rctl);
2038 	} else {
2039 		e1000_update_mc_addr_list(&adapter->hw, mta, mcnt);
2040 	}
2041 
2042 	if (adapter->hw.mac.type == e1000_82542 &&
2043 	    adapter->hw.revision_id == E1000_REVISION_2) {
2044 		reg_rctl = E1000_READ_REG(&adapter->hw, E1000_RCTL);
2045 		reg_rctl &= ~E1000_RCTL_RST;
2046 		E1000_WRITE_REG(&adapter->hw, E1000_RCTL, reg_rctl);
2047 		msec_delay(5);
2048 		if (adapter->hw.bus.pci_cmd_word & CMD_MEM_WRT_INVALIDATE)
2049 			e1000_pci_set_mwi(&adapter->hw);
2050 	}
2051 }
2052 
2053 /*
2054  * This routine checks for link status and updates statistics.
2055  */
2056 static void
2057 em_timer(void *xsc)
2058 {
2059 	struct adapter *adapter = xsc;
2060 	struct ifnet *ifp = &adapter->arpcom.ac_if;
2061 
2062 	lwkt_serialize_enter(ifp->if_serializer);
2063 
2064 	em_update_link_status(adapter);
2065 	em_update_stats(adapter);
2066 
2067 	/* Reset LAA into RAR[0] on 82571 */
2068 	if (e1000_get_laa_state_82571(&adapter->hw) == TRUE)
2069 		e1000_rar_set(&adapter->hw, adapter->hw.mac.addr, 0);
2070 
2071 	if (em_display_debug_stats && (ifp->if_flags & IFF_RUNNING))
2072 		em_print_hw_stats(adapter);
2073 
2074 	em_smartspeed(adapter);
2075 
2076 	callout_reset(&adapter->timer, hz, em_timer, adapter);
2077 
2078 	lwkt_serialize_exit(ifp->if_serializer);
2079 }
2080 
2081 static void
2082 em_update_link_status(struct adapter *adapter)
2083 {
2084 	struct e1000_hw *hw = &adapter->hw;
2085 	struct ifnet *ifp = &adapter->arpcom.ac_if;
2086 	device_t dev = adapter->dev;
2087 	uint32_t link_check = 0;
2088 
2089 	/* Get the cached link value or read phy for real */
2090 	switch (hw->phy.media_type) {
2091 	case e1000_media_type_copper:
2092 		if (hw->mac.get_link_status) {
2093 			/* Do the work to read phy */
2094 			e1000_check_for_link(hw);
2095 			link_check = !hw->mac.get_link_status;
2096 			if (link_check) /* ESB2 fix */
2097 				e1000_cfg_on_link_up(hw);
2098 		} else {
2099 			link_check = TRUE;
2100 		}
2101 		break;
2102 
2103 	case e1000_media_type_fiber:
2104 		e1000_check_for_link(hw);
2105 		link_check =
2106 			E1000_READ_REG(hw, E1000_STATUS) & E1000_STATUS_LU;
2107 		break;
2108 
2109 	case e1000_media_type_internal_serdes:
2110 		e1000_check_for_link(hw);
2111 		link_check = adapter->hw.mac.serdes_has_link;
2112 		break;
2113 
2114 	case e1000_media_type_unknown:
2115 	default:
2116 		break;
2117 	}
2118 
2119 	/* Now check for a transition */
2120 	if (link_check && adapter->link_active == 0) {
2121 		e1000_get_speed_and_duplex(hw, &adapter->link_speed,
2122 		    &adapter->link_duplex);
2123 
2124 		/*
2125 		 * Check if we should enable/disable SPEED_MODE bit on
2126 		 * 82571/82572
2127 		 */
2128 		if (adapter->link_speed != SPEED_1000 &&
2129 		    (hw->mac.type == e1000_82571 ||
2130 		     hw->mac.type == e1000_82572)) {
2131 			int tarc0;
2132 
2133 			tarc0 = E1000_READ_REG(hw, E1000_TARC(0));
2134 			tarc0 &= ~SPEED_MODE_BIT;
2135 			E1000_WRITE_REG(hw, E1000_TARC(0), tarc0);
2136 		}
2137 		if (bootverbose) {
2138 			device_printf(dev, "Link is up %d Mbps %s\n",
2139 			    adapter->link_speed,
2140 			    ((adapter->link_duplex == FULL_DUPLEX) ?
2141 			    "Full Duplex" : "Half Duplex"));
2142 		}
2143 		adapter->link_active = 1;
2144 		adapter->smartspeed = 0;
2145 		ifp->if_baudrate = adapter->link_speed * 1000000;
2146 		ifp->if_link_state = LINK_STATE_UP;
2147 		if_link_state_change(ifp);
2148 	} else if (!link_check && adapter->link_active == 1) {
2149 		ifp->if_baudrate = adapter->link_speed = 0;
2150 		adapter->link_duplex = 0;
2151 		if (bootverbose)
2152 			device_printf(dev, "Link is Down\n");
2153 		adapter->link_active = 0;
2154 #if 0
2155 		/* Link down, disable watchdog */
2156 		if->if_timer = 0;
2157 #endif
2158 		ifp->if_link_state = LINK_STATE_DOWN;
2159 		if_link_state_change(ifp);
2160 	}
2161 }
2162 
2163 static void
2164 em_stop(struct adapter *adapter)
2165 {
2166 	struct ifnet *ifp = &adapter->arpcom.ac_if;
2167 	int i;
2168 
2169 	ASSERT_SERIALIZED(ifp->if_serializer);
2170 
2171 	em_disable_intr(adapter);
2172 
2173 	callout_stop(&adapter->timer);
2174 	callout_stop(&adapter->tx_fifo_timer);
2175 
2176 	ifp->if_flags &= ~IFF_RUNNING;
2177 	ifq_clr_oactive(&ifp->if_snd);
2178 	ifp->if_timer = 0;
2179 
2180 	e1000_reset_hw(&adapter->hw);
2181 	if (adapter->hw.mac.type >= e1000_82544)
2182 		E1000_WRITE_REG(&adapter->hw, E1000_WUC, 0);
2183 
2184 	for (i = 0; i < adapter->num_tx_desc; i++) {
2185 		struct em_buffer *tx_buffer = &adapter->tx_buffer_area[i];
2186 
2187 		if (tx_buffer->m_head != NULL) {
2188 			bus_dmamap_unload(adapter->txtag, tx_buffer->map);
2189 			m_freem(tx_buffer->m_head);
2190 			tx_buffer->m_head = NULL;
2191 		}
2192 	}
2193 
2194 	for (i = 0; i < adapter->num_rx_desc; i++) {
2195 		struct em_buffer *rx_buffer = &adapter->rx_buffer_area[i];
2196 
2197 		if (rx_buffer->m_head != NULL) {
2198 			bus_dmamap_unload(adapter->rxtag, rx_buffer->map);
2199 			m_freem(rx_buffer->m_head);
2200 			rx_buffer->m_head = NULL;
2201 		}
2202 	}
2203 
2204 	if (adapter->fmp != NULL)
2205 		m_freem(adapter->fmp);
2206 	adapter->fmp = NULL;
2207 	adapter->lmp = NULL;
2208 
2209 	adapter->csum_flags = 0;
2210 	adapter->csum_lhlen = 0;
2211 	adapter->csum_iphlen = 0;
2212 	adapter->csum_thlen = 0;
2213 	adapter->csum_mss = 0;
2214 	adapter->csum_pktlen = 0;
2215 
2216 	adapter->tx_dd_head = 0;
2217 	adapter->tx_dd_tail = 0;
2218 	adapter->tx_nsegs = 0;
2219 }
2220 
2221 static int
2222 em_get_hw_info(struct adapter *adapter)
2223 {
2224 	device_t dev = adapter->dev;
2225 
2226 	/* Save off the information about this board */
2227 	adapter->hw.vendor_id = pci_get_vendor(dev);
2228 	adapter->hw.device_id = pci_get_device(dev);
2229 	adapter->hw.revision_id = pci_get_revid(dev);
2230 	adapter->hw.subsystem_vendor_id = pci_get_subvendor(dev);
2231 	adapter->hw.subsystem_device_id = pci_get_subdevice(dev);
2232 
2233 	/* Do Shared Code Init and Setup */
2234 	if (e1000_set_mac_type(&adapter->hw))
2235 		return ENXIO;
2236 	return 0;
2237 }
2238 
2239 static int
2240 em_alloc_pci_res(struct adapter *adapter)
2241 {
2242 	device_t dev = adapter->dev;
2243 	u_int intr_flags;
2244 	int val, rid, msi_enable;
2245 
2246 	/* Enable bus mastering */
2247 	pci_enable_busmaster(dev);
2248 
2249 	adapter->memory_rid = EM_BAR_MEM;
2250 	adapter->memory = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
2251 				&adapter->memory_rid, RF_ACTIVE);
2252 	if (adapter->memory == NULL) {
2253 		device_printf(dev, "Unable to allocate bus resource: memory\n");
2254 		return (ENXIO);
2255 	}
2256 	adapter->osdep.mem_bus_space_tag =
2257 	    rman_get_bustag(adapter->memory);
2258 	adapter->osdep.mem_bus_space_handle =
2259 	    rman_get_bushandle(adapter->memory);
2260 
2261 	/* XXX This is quite goofy, it is not actually used */
2262 	adapter->hw.hw_addr = (uint8_t *)&adapter->osdep.mem_bus_space_handle;
2263 
2264 	/* Only older adapters use IO mapping */
2265 	if (adapter->hw.mac.type > e1000_82543 &&
2266 	    adapter->hw.mac.type < e1000_82571) {
2267 		/* Figure our where our IO BAR is ? */
2268 		for (rid = PCIR_BAR(0); rid < PCIR_CARDBUSCIS;) {
2269 			val = pci_read_config(dev, rid, 4);
2270 			if (EM_BAR_TYPE(val) == EM_BAR_TYPE_IO) {
2271 				adapter->io_rid = rid;
2272 				break;
2273 			}
2274 			rid += 4;
2275 			/* check for 64bit BAR */
2276 			if (EM_BAR_MEM_TYPE(val) == EM_BAR_MEM_TYPE_64BIT)
2277 				rid += 4;
2278 		}
2279 		if (rid >= PCIR_CARDBUSCIS) {
2280 			device_printf(dev, "Unable to locate IO BAR\n");
2281 			return (ENXIO);
2282 		}
2283 		adapter->ioport = bus_alloc_resource_any(dev, SYS_RES_IOPORT,
2284 					&adapter->io_rid, RF_ACTIVE);
2285 		if (adapter->ioport == NULL) {
2286 			device_printf(dev, "Unable to allocate bus resource: "
2287 			    "ioport\n");
2288 			return (ENXIO);
2289 		}
2290 		adapter->hw.io_base = 0;
2291 		adapter->osdep.io_bus_space_tag =
2292 		    rman_get_bustag(adapter->ioport);
2293 		adapter->osdep.io_bus_space_handle =
2294 		    rman_get_bushandle(adapter->ioport);
2295 	}
2296 
2297 	/*
2298 	 * Don't enable MSI-X on 82574, see:
2299 	 * 82574 specification update errata #15
2300 	 *
2301 	 * Don't enable MSI on PCI/PCI-X chips, see:
2302 	 * 82540 specification update errata #6
2303 	 * 82545 specification update errata #4
2304 	 *
2305 	 * Don't enable MSI on 82571/82572, see:
2306 	 * 82571/82572 specification update errata #63
2307 	 */
2308 	msi_enable = em_msi_enable;
2309 	if (msi_enable &&
2310 	    (!pci_is_pcie(dev) ||
2311 	     adapter->hw.mac.type == e1000_82571 ||
2312 	     adapter->hw.mac.type == e1000_82572))
2313 		msi_enable = 0;
2314 
2315 	adapter->intr_type = pci_alloc_1intr(dev, msi_enable,
2316 	    &adapter->intr_rid, &intr_flags);
2317 
2318 	if (adapter->intr_type == PCI_INTR_TYPE_LEGACY) {
2319 		int unshared;
2320 
2321 		unshared = device_getenv_int(dev, "irq.unshared", 0);
2322 		if (!unshared) {
2323 			adapter->flags |= EM_FLAG_SHARED_INTR;
2324 			if (bootverbose)
2325 				device_printf(dev, "IRQ shared\n");
2326 		} else {
2327 			intr_flags &= ~RF_SHAREABLE;
2328 			if (bootverbose)
2329 				device_printf(dev, "IRQ unshared\n");
2330 		}
2331 	}
2332 
2333 	adapter->intr_res = bus_alloc_resource_any(dev, SYS_RES_IRQ,
2334 	    &adapter->intr_rid, intr_flags);
2335 	if (adapter->intr_res == NULL) {
2336 		device_printf(dev, "Unable to allocate bus resource: "
2337 		    "interrupt\n");
2338 		return (ENXIO);
2339 	}
2340 
2341 	adapter->hw.bus.pci_cmd_word = pci_read_config(dev, PCIR_COMMAND, 2);
2342 	adapter->hw.back = &adapter->osdep;
2343 	return (0);
2344 }
2345 
2346 static void
2347 em_free_pci_res(struct adapter *adapter)
2348 {
2349 	device_t dev = adapter->dev;
2350 
2351 	if (adapter->intr_res != NULL) {
2352 		bus_release_resource(dev, SYS_RES_IRQ,
2353 		    adapter->intr_rid, adapter->intr_res);
2354 	}
2355 
2356 	if (adapter->intr_type == PCI_INTR_TYPE_MSI)
2357 		pci_release_msi(dev);
2358 
2359 	if (adapter->memory != NULL) {
2360 		bus_release_resource(dev, SYS_RES_MEMORY,
2361 		    adapter->memory_rid, adapter->memory);
2362 	}
2363 
2364 	if (adapter->flash != NULL) {
2365 		bus_release_resource(dev, SYS_RES_MEMORY,
2366 		    adapter->flash_rid, adapter->flash);
2367 	}
2368 
2369 	if (adapter->ioport != NULL) {
2370 		bus_release_resource(dev, SYS_RES_IOPORT,
2371 		    adapter->io_rid, adapter->ioport);
2372 	}
2373 }
2374 
2375 static int
2376 em_reset(struct adapter *adapter)
2377 {
2378 	device_t dev = adapter->dev;
2379 	uint16_t rx_buffer_size;
2380 
2381 	/* When hardware is reset, fifo_head is also reset */
2382 	adapter->tx_fifo_head = 0;
2383 
2384 	/* Set up smart power down as default off on newer adapters. */
2385 	if (!em_smart_pwr_down &&
2386 	    (adapter->hw.mac.type == e1000_82571 ||
2387 	     adapter->hw.mac.type == e1000_82572)) {
2388 		uint16_t phy_tmp = 0;
2389 
2390 		/* Speed up time to link by disabling smart power down. */
2391 		e1000_read_phy_reg(&adapter->hw,
2392 		    IGP02E1000_PHY_POWER_MGMT, &phy_tmp);
2393 		phy_tmp &= ~IGP02E1000_PM_SPD;
2394 		e1000_write_phy_reg(&adapter->hw,
2395 		    IGP02E1000_PHY_POWER_MGMT, phy_tmp);
2396 	}
2397 
2398 	/*
2399 	 * These parameters control the automatic generation (Tx) and
2400 	 * response (Rx) to Ethernet PAUSE frames.
2401 	 * - High water mark should allow for at least two frames to be
2402 	 *   received after sending an XOFF.
2403 	 * - Low water mark works best when it is very near the high water mark.
2404 	 *   This allows the receiver to restart by sending XON when it has
2405 	 *   drained a bit. Here we use an arbitary value of 1500 which will
2406 	 *   restart after one full frame is pulled from the buffer. There
2407 	 *   could be several smaller frames in the buffer and if so they will
2408 	 *   not trigger the XON until their total number reduces the buffer
2409 	 *   by 1500.
2410 	 * - The pause time is fairly large at 1000 x 512ns = 512 usec.
2411 	 */
2412 	rx_buffer_size =
2413 		(E1000_READ_REG(&adapter->hw, E1000_PBA) & 0xffff) << 10;
2414 
2415 	adapter->hw.fc.high_water = rx_buffer_size -
2416 				    roundup2(adapter->max_frame_size, 1024);
2417 	adapter->hw.fc.low_water = adapter->hw.fc.high_water - 1500;
2418 
2419 	if (adapter->hw.mac.type == e1000_80003es2lan)
2420 		adapter->hw.fc.pause_time = 0xFFFF;
2421 	else
2422 		adapter->hw.fc.pause_time = EM_FC_PAUSE_TIME;
2423 
2424 	adapter->hw.fc.send_xon = TRUE;
2425 
2426 	adapter->hw.fc.requested_mode = e1000_fc_full;
2427 
2428 	/* Workaround: no TX flow ctrl for PCH */
2429 	if (adapter->hw.mac.type == e1000_pchlan)
2430 		adapter->hw.fc.requested_mode = e1000_fc_rx_pause;
2431 
2432 	/* Override - settings for PCH2LAN, ya its magic :) */
2433 	if (adapter->hw.mac.type == e1000_pch2lan) {
2434 		adapter->hw.fc.high_water = 0x5C20;
2435 		adapter->hw.fc.low_water = 0x5048;
2436 		adapter->hw.fc.pause_time = 0x0650;
2437 		adapter->hw.fc.refresh_time = 0x0400;
2438 
2439 		/* Jumbos need adjusted PBA */
2440 		if (adapter->arpcom.ac_if.if_mtu > ETHERMTU)
2441 			E1000_WRITE_REG(&adapter->hw, E1000_PBA, 12);
2442 		else
2443 			E1000_WRITE_REG(&adapter->hw, E1000_PBA, 26);
2444 	}
2445 
2446 	/* Issue a global reset */
2447 	e1000_reset_hw(&adapter->hw);
2448 	if (adapter->hw.mac.type >= e1000_82544)
2449 		E1000_WRITE_REG(&adapter->hw, E1000_WUC, 0);
2450 	em_disable_aspm(adapter);
2451 
2452 	if (e1000_init_hw(&adapter->hw) < 0) {
2453 		device_printf(dev, "Hardware Initialization Failed\n");
2454 		return (EIO);
2455 	}
2456 
2457 	E1000_WRITE_REG(&adapter->hw, E1000_VET, ETHERTYPE_VLAN);
2458 	e1000_get_phy_info(&adapter->hw);
2459 	e1000_check_for_link(&adapter->hw);
2460 
2461 	return (0);
2462 }
2463 
2464 static void
2465 em_setup_ifp(struct adapter *adapter)
2466 {
2467 	struct ifnet *ifp = &adapter->arpcom.ac_if;
2468 
2469 	if_initname(ifp, device_get_name(adapter->dev),
2470 		    device_get_unit(adapter->dev));
2471 	ifp->if_softc = adapter;
2472 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
2473 	ifp->if_init =  em_init;
2474 	ifp->if_ioctl = em_ioctl;
2475 	ifp->if_start = em_start;
2476 #ifdef IFPOLL_ENABLE
2477 	ifp->if_npoll = em_npoll;
2478 #endif
2479 	ifp->if_watchdog = em_watchdog;
2480 	ifq_set_maxlen(&ifp->if_snd, adapter->num_tx_desc - 1);
2481 	ifq_set_ready(&ifp->if_snd);
2482 
2483 	ether_ifattach(ifp, adapter->hw.mac.addr, NULL);
2484 
2485 	ifp->if_capabilities = IFCAP_VLAN_HWTAGGING | IFCAP_VLAN_MTU;
2486 	if (adapter->hw.mac.type >= e1000_82543)
2487 		ifp->if_capabilities |= IFCAP_HWCSUM;
2488 	if (adapter->flags & EM_FLAG_TSO)
2489 		ifp->if_capabilities |= IFCAP_TSO;
2490 	ifp->if_capenable = ifp->if_capabilities;
2491 
2492 	if (ifp->if_capenable & IFCAP_TXCSUM)
2493 		ifp->if_hwassist |= EM_CSUM_FEATURES;
2494 	if (ifp->if_capenable & IFCAP_TSO)
2495 		ifp->if_hwassist |= CSUM_TSO;
2496 
2497 	/*
2498 	 * Tell the upper layer(s) we support long frames.
2499 	 */
2500 	ifp->if_data.ifi_hdrlen = sizeof(struct ether_vlan_header);
2501 
2502 	/*
2503 	 * Specify the media types supported by this adapter and register
2504 	 * callbacks to update media and link information
2505 	 */
2506 	ifmedia_init(&adapter->media, IFM_IMASK,
2507 		     em_media_change, em_media_status);
2508 	if (adapter->hw.phy.media_type == e1000_media_type_fiber ||
2509 	    adapter->hw.phy.media_type == e1000_media_type_internal_serdes) {
2510 		u_char fiber_type = IFM_1000_SX; /* default type */
2511 
2512 		if (adapter->hw.mac.type == e1000_82545)
2513 			fiber_type = IFM_1000_LX;
2514 		ifmedia_add(&adapter->media, IFM_ETHER | fiber_type | IFM_FDX,
2515 			    0, NULL);
2516 		ifmedia_add(&adapter->media, IFM_ETHER | fiber_type, 0, NULL);
2517 	} else {
2518 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_10_T, 0, NULL);
2519 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_10_T | IFM_FDX,
2520 			    0, NULL);
2521 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_100_TX,
2522 			    0, NULL);
2523 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_100_TX | IFM_FDX,
2524 			    0, NULL);
2525 		if (adapter->hw.phy.type != e1000_phy_ife) {
2526 			ifmedia_add(&adapter->media,
2527 				IFM_ETHER | IFM_1000_T | IFM_FDX, 0, NULL);
2528 			ifmedia_add(&adapter->media,
2529 				IFM_ETHER | IFM_1000_T, 0, NULL);
2530 		}
2531 	}
2532 	ifmedia_add(&adapter->media, IFM_ETHER | IFM_AUTO, 0, NULL);
2533 	ifmedia_set(&adapter->media, IFM_ETHER | IFM_AUTO);
2534 }
2535 
2536 
2537 /*
2538  * Workaround for SmartSpeed on 82541 and 82547 controllers
2539  */
2540 static void
2541 em_smartspeed(struct adapter *adapter)
2542 {
2543 	uint16_t phy_tmp;
2544 
2545 	if (adapter->link_active || adapter->hw.phy.type != e1000_phy_igp ||
2546 	    adapter->hw.mac.autoneg == 0 ||
2547 	    (adapter->hw.phy.autoneg_advertised & ADVERTISE_1000_FULL) == 0)
2548 		return;
2549 
2550 	if (adapter->smartspeed == 0) {
2551 		/*
2552 		 * If Master/Slave config fault is asserted twice,
2553 		 * we assume back-to-back
2554 		 */
2555 		e1000_read_phy_reg(&adapter->hw, PHY_1000T_STATUS, &phy_tmp);
2556 		if (!(phy_tmp & SR_1000T_MS_CONFIG_FAULT))
2557 			return;
2558 		e1000_read_phy_reg(&adapter->hw, PHY_1000T_STATUS, &phy_tmp);
2559 		if (phy_tmp & SR_1000T_MS_CONFIG_FAULT) {
2560 			e1000_read_phy_reg(&adapter->hw,
2561 			    PHY_1000T_CTRL, &phy_tmp);
2562 			if (phy_tmp & CR_1000T_MS_ENABLE) {
2563 				phy_tmp &= ~CR_1000T_MS_ENABLE;
2564 				e1000_write_phy_reg(&adapter->hw,
2565 				    PHY_1000T_CTRL, phy_tmp);
2566 				adapter->smartspeed++;
2567 				if (adapter->hw.mac.autoneg &&
2568 				    !e1000_phy_setup_autoneg(&adapter->hw) &&
2569 				    !e1000_read_phy_reg(&adapter->hw,
2570 				     PHY_CONTROL, &phy_tmp)) {
2571 					phy_tmp |= MII_CR_AUTO_NEG_EN |
2572 						   MII_CR_RESTART_AUTO_NEG;
2573 					e1000_write_phy_reg(&adapter->hw,
2574 					    PHY_CONTROL, phy_tmp);
2575 				}
2576 			}
2577 		}
2578 		return;
2579 	} else if (adapter->smartspeed == EM_SMARTSPEED_DOWNSHIFT) {
2580 		/* If still no link, perhaps using 2/3 pair cable */
2581 		e1000_read_phy_reg(&adapter->hw, PHY_1000T_CTRL, &phy_tmp);
2582 		phy_tmp |= CR_1000T_MS_ENABLE;
2583 		e1000_write_phy_reg(&adapter->hw, PHY_1000T_CTRL, phy_tmp);
2584 		if (adapter->hw.mac.autoneg &&
2585 		    !e1000_phy_setup_autoneg(&adapter->hw) &&
2586 		    !e1000_read_phy_reg(&adapter->hw, PHY_CONTROL, &phy_tmp)) {
2587 			phy_tmp |= MII_CR_AUTO_NEG_EN | MII_CR_RESTART_AUTO_NEG;
2588 			e1000_write_phy_reg(&adapter->hw, PHY_CONTROL, phy_tmp);
2589 		}
2590 	}
2591 
2592 	/* Restart process after EM_SMARTSPEED_MAX iterations */
2593 	if (adapter->smartspeed++ == EM_SMARTSPEED_MAX)
2594 		adapter->smartspeed = 0;
2595 }
2596 
2597 static int
2598 em_dma_malloc(struct adapter *adapter, bus_size_t size,
2599 	      struct em_dma_alloc *dma)
2600 {
2601 	dma->dma_vaddr = bus_dmamem_coherent_any(adapter->parent_dtag,
2602 				EM_DBA_ALIGN, size, BUS_DMA_WAITOK,
2603 				&dma->dma_tag, &dma->dma_map,
2604 				&dma->dma_paddr);
2605 	if (dma->dma_vaddr == NULL)
2606 		return ENOMEM;
2607 	else
2608 		return 0;
2609 }
2610 
2611 static void
2612 em_dma_free(struct adapter *adapter, struct em_dma_alloc *dma)
2613 {
2614 	if (dma->dma_tag == NULL)
2615 		return;
2616 	bus_dmamap_unload(dma->dma_tag, dma->dma_map);
2617 	bus_dmamem_free(dma->dma_tag, dma->dma_vaddr, dma->dma_map);
2618 	bus_dma_tag_destroy(dma->dma_tag);
2619 }
2620 
2621 static int
2622 em_create_tx_ring(struct adapter *adapter)
2623 {
2624 	device_t dev = adapter->dev;
2625 	struct em_buffer *tx_buffer;
2626 	int error, i;
2627 
2628 	adapter->tx_buffer_area =
2629 		kmalloc(sizeof(struct em_buffer) * adapter->num_tx_desc,
2630 			M_DEVBUF, M_WAITOK | M_ZERO);
2631 
2632 	/*
2633 	 * Create DMA tags for tx buffers
2634 	 */
2635 	error = bus_dma_tag_create(adapter->parent_dtag, /* parent */
2636 			1, 0,			/* alignment, bounds */
2637 			BUS_SPACE_MAXADDR,	/* lowaddr */
2638 			BUS_SPACE_MAXADDR,	/* highaddr */
2639 			NULL, NULL,		/* filter, filterarg */
2640 			EM_TSO_SIZE,		/* maxsize */
2641 			EM_MAX_SCATTER,		/* nsegments */
2642 			PAGE_SIZE,		/* maxsegsize */
2643 			BUS_DMA_WAITOK | BUS_DMA_ALLOCNOW |
2644 			BUS_DMA_ONEBPAGE,	/* flags */
2645 			&adapter->txtag);
2646 	if (error) {
2647 		device_printf(dev, "Unable to allocate TX DMA tag\n");
2648 		kfree(adapter->tx_buffer_area, M_DEVBUF);
2649 		adapter->tx_buffer_area = NULL;
2650 		return error;
2651 	}
2652 
2653 	/*
2654 	 * Create DMA maps for tx buffers
2655 	 */
2656 	for (i = 0; i < adapter->num_tx_desc; i++) {
2657 		tx_buffer = &adapter->tx_buffer_area[i];
2658 
2659 		error = bus_dmamap_create(adapter->txtag,
2660 					  BUS_DMA_WAITOK | BUS_DMA_ONEBPAGE,
2661 					  &tx_buffer->map);
2662 		if (error) {
2663 			device_printf(dev, "Unable to create TX DMA map\n");
2664 			em_destroy_tx_ring(adapter, i);
2665 			return error;
2666 		}
2667 	}
2668 	return (0);
2669 }
2670 
2671 static void
2672 em_init_tx_ring(struct adapter *adapter)
2673 {
2674 	/* Clear the old ring contents */
2675 	bzero(adapter->tx_desc_base,
2676 	    (sizeof(struct e1000_tx_desc)) * adapter->num_tx_desc);
2677 
2678 	/* Reset state */
2679 	adapter->next_avail_tx_desc = 0;
2680 	adapter->next_tx_to_clean = 0;
2681 	adapter->num_tx_desc_avail = adapter->num_tx_desc;
2682 }
2683 
2684 static void
2685 em_init_tx_unit(struct adapter *adapter)
2686 {
2687 	uint32_t tctl, tarc, tipg = 0;
2688 	uint64_t bus_addr;
2689 
2690 	/* Setup the Base and Length of the Tx Descriptor Ring */
2691 	bus_addr = adapter->txdma.dma_paddr;
2692 	E1000_WRITE_REG(&adapter->hw, E1000_TDLEN(0),
2693 	    adapter->num_tx_desc * sizeof(struct e1000_tx_desc));
2694 	E1000_WRITE_REG(&adapter->hw, E1000_TDBAH(0),
2695 	    (uint32_t)(bus_addr >> 32));
2696 	E1000_WRITE_REG(&adapter->hw, E1000_TDBAL(0),
2697 	    (uint32_t)bus_addr);
2698 	/* Setup the HW Tx Head and Tail descriptor pointers */
2699 	E1000_WRITE_REG(&adapter->hw, E1000_TDT(0), 0);
2700 	E1000_WRITE_REG(&adapter->hw, E1000_TDH(0), 0);
2701 
2702 	/* Set the default values for the Tx Inter Packet Gap timer */
2703 	switch (adapter->hw.mac.type) {
2704 	case e1000_82542:
2705 		tipg = DEFAULT_82542_TIPG_IPGT;
2706 		tipg |= DEFAULT_82542_TIPG_IPGR1 << E1000_TIPG_IPGR1_SHIFT;
2707 		tipg |= DEFAULT_82542_TIPG_IPGR2 << E1000_TIPG_IPGR2_SHIFT;
2708 		break;
2709 
2710 	case e1000_80003es2lan:
2711 		tipg = DEFAULT_82543_TIPG_IPGR1;
2712 		tipg |= DEFAULT_80003ES2LAN_TIPG_IPGR2 <<
2713 		    E1000_TIPG_IPGR2_SHIFT;
2714 		break;
2715 
2716 	default:
2717 		if (adapter->hw.phy.media_type == e1000_media_type_fiber ||
2718 		    adapter->hw.phy.media_type ==
2719 		    e1000_media_type_internal_serdes)
2720 			tipg = DEFAULT_82543_TIPG_IPGT_FIBER;
2721 		else
2722 			tipg = DEFAULT_82543_TIPG_IPGT_COPPER;
2723 		tipg |= DEFAULT_82543_TIPG_IPGR1 << E1000_TIPG_IPGR1_SHIFT;
2724 		tipg |= DEFAULT_82543_TIPG_IPGR2 << E1000_TIPG_IPGR2_SHIFT;
2725 		break;
2726 	}
2727 
2728 	E1000_WRITE_REG(&adapter->hw, E1000_TIPG, tipg);
2729 
2730 	/* NOTE: 0 is not allowed for TIDV */
2731 	E1000_WRITE_REG(&adapter->hw, E1000_TIDV, 1);
2732 	if(adapter->hw.mac.type >= e1000_82540)
2733 		E1000_WRITE_REG(&adapter->hw, E1000_TADV, 0);
2734 
2735 	if (adapter->hw.mac.type == e1000_82571 ||
2736 	    adapter->hw.mac.type == e1000_82572) {
2737 		tarc = E1000_READ_REG(&adapter->hw, E1000_TARC(0));
2738 		tarc |= SPEED_MODE_BIT;
2739 		E1000_WRITE_REG(&adapter->hw, E1000_TARC(0), tarc);
2740 	} else if (adapter->hw.mac.type == e1000_80003es2lan) {
2741 		tarc = E1000_READ_REG(&adapter->hw, E1000_TARC(0));
2742 		tarc |= 1;
2743 		E1000_WRITE_REG(&adapter->hw, E1000_TARC(0), tarc);
2744 		tarc = E1000_READ_REG(&adapter->hw, E1000_TARC(1));
2745 		tarc |= 1;
2746 		E1000_WRITE_REG(&adapter->hw, E1000_TARC(1), tarc);
2747 	}
2748 
2749 	/* Program the Transmit Control Register */
2750 	tctl = E1000_READ_REG(&adapter->hw, E1000_TCTL);
2751 	tctl &= ~E1000_TCTL_CT;
2752 	tctl |= E1000_TCTL_PSP | E1000_TCTL_RTLC | E1000_TCTL_EN |
2753 		(E1000_COLLISION_THRESHOLD << E1000_CT_SHIFT);
2754 
2755 	if (adapter->hw.mac.type >= e1000_82571)
2756 		tctl |= E1000_TCTL_MULR;
2757 
2758 	/* This write will effectively turn on the transmit unit. */
2759 	E1000_WRITE_REG(&adapter->hw, E1000_TCTL, tctl);
2760 }
2761 
2762 static void
2763 em_destroy_tx_ring(struct adapter *adapter, int ndesc)
2764 {
2765 	struct em_buffer *tx_buffer;
2766 	int i;
2767 
2768 	if (adapter->tx_buffer_area == NULL)
2769 		return;
2770 
2771 	for (i = 0; i < ndesc; i++) {
2772 		tx_buffer = &adapter->tx_buffer_area[i];
2773 
2774 		KKASSERT(tx_buffer->m_head == NULL);
2775 		bus_dmamap_destroy(adapter->txtag, tx_buffer->map);
2776 	}
2777 	bus_dma_tag_destroy(adapter->txtag);
2778 
2779 	kfree(adapter->tx_buffer_area, M_DEVBUF);
2780 	adapter->tx_buffer_area = NULL;
2781 }
2782 
2783 /*
2784  * The offload context needs to be set when we transfer the first
2785  * packet of a particular protocol (TCP/UDP).  This routine has been
2786  * enhanced to deal with inserted VLAN headers.
2787  *
2788  * If the new packet's ether header length, ip header length and
2789  * csum offloading type are same as the previous packet, we should
2790  * avoid allocating a new csum context descriptor; mainly to take
2791  * advantage of the pipeline effect of the TX data read request.
2792  *
2793  * This function returns number of TX descrptors allocated for
2794  * csum context.
2795  */
2796 static int
2797 em_txcsum(struct adapter *adapter, struct mbuf *mp,
2798 	  uint32_t *txd_upper, uint32_t *txd_lower)
2799 {
2800 	struct e1000_context_desc *TXD;
2801 	int curr_txd, ehdrlen, csum_flags;
2802 	uint32_t cmd, hdr_len, ip_hlen;
2803 
2804 	csum_flags = mp->m_pkthdr.csum_flags & EM_CSUM_FEATURES;
2805 	ip_hlen = mp->m_pkthdr.csum_iphlen;
2806 	ehdrlen = mp->m_pkthdr.csum_lhlen;
2807 
2808 	if (adapter->csum_lhlen == ehdrlen &&
2809 	    adapter->csum_iphlen == ip_hlen &&
2810 	    adapter->csum_flags == csum_flags) {
2811 		/*
2812 		 * Same csum offload context as the previous packets;
2813 		 * just return.
2814 		 */
2815 		*txd_upper = adapter->csum_txd_upper;
2816 		*txd_lower = adapter->csum_txd_lower;
2817 		return 0;
2818 	}
2819 
2820 	/*
2821 	 * Setup a new csum offload context.
2822 	 */
2823 
2824 	curr_txd = adapter->next_avail_tx_desc;
2825 	TXD = (struct e1000_context_desc *)&adapter->tx_desc_base[curr_txd];
2826 
2827 	cmd = 0;
2828 
2829 	/* Setup of IP header checksum. */
2830 	if (csum_flags & CSUM_IP) {
2831 		/*
2832 		 * Start offset for header checksum calculation.
2833 		 * End offset for header checksum calculation.
2834 		 * Offset of place to put the checksum.
2835 		 */
2836 		TXD->lower_setup.ip_fields.ipcss = ehdrlen;
2837 		TXD->lower_setup.ip_fields.ipcse =
2838 		    htole16(ehdrlen + ip_hlen - 1);
2839 		TXD->lower_setup.ip_fields.ipcso =
2840 		    ehdrlen + offsetof(struct ip, ip_sum);
2841 		cmd |= E1000_TXD_CMD_IP;
2842 		*txd_upper |= E1000_TXD_POPTS_IXSM << 8;
2843 	}
2844 	hdr_len = ehdrlen + ip_hlen;
2845 
2846 	if (csum_flags & CSUM_TCP) {
2847 		/*
2848 		 * Start offset for payload checksum calculation.
2849 		 * End offset for payload checksum calculation.
2850 		 * Offset of place to put the checksum.
2851 		 */
2852 		TXD->upper_setup.tcp_fields.tucss = hdr_len;
2853 		TXD->upper_setup.tcp_fields.tucse = htole16(0);
2854 		TXD->upper_setup.tcp_fields.tucso =
2855 		    hdr_len + offsetof(struct tcphdr, th_sum);
2856 		cmd |= E1000_TXD_CMD_TCP;
2857 		*txd_upper |= E1000_TXD_POPTS_TXSM << 8;
2858 	} else if (csum_flags & CSUM_UDP) {
2859 		/*
2860 		 * Start offset for header checksum calculation.
2861 		 * End offset for header checksum calculation.
2862 		 * Offset of place to put the checksum.
2863 		 */
2864 		TXD->upper_setup.tcp_fields.tucss = hdr_len;
2865 		TXD->upper_setup.tcp_fields.tucse = htole16(0);
2866 		TXD->upper_setup.tcp_fields.tucso =
2867 		    hdr_len + offsetof(struct udphdr, uh_sum);
2868 		*txd_upper |= E1000_TXD_POPTS_TXSM << 8;
2869 	}
2870 
2871 	*txd_lower = E1000_TXD_CMD_DEXT |	/* Extended descr type */
2872 		     E1000_TXD_DTYP_D;		/* Data descr */
2873 
2874 	/* Save the information for this csum offloading context */
2875 	adapter->csum_lhlen = ehdrlen;
2876 	adapter->csum_iphlen = ip_hlen;
2877 	adapter->csum_flags = csum_flags;
2878 	adapter->csum_txd_upper = *txd_upper;
2879 	adapter->csum_txd_lower = *txd_lower;
2880 
2881 	TXD->tcp_seg_setup.data = htole32(0);
2882 	TXD->cmd_and_length =
2883 	    htole32(E1000_TXD_CMD_IFCS | E1000_TXD_CMD_DEXT | cmd);
2884 
2885 	if (++curr_txd == adapter->num_tx_desc)
2886 		curr_txd = 0;
2887 
2888 	KKASSERT(adapter->num_tx_desc_avail > 0);
2889 	adapter->num_tx_desc_avail--;
2890 
2891 	adapter->next_avail_tx_desc = curr_txd;
2892 	return 1;
2893 }
2894 
2895 static void
2896 em_txeof(struct adapter *adapter)
2897 {
2898 	struct ifnet *ifp = &adapter->arpcom.ac_if;
2899 	struct em_buffer *tx_buffer;
2900 	int first, num_avail;
2901 
2902 	if (adapter->tx_dd_head == adapter->tx_dd_tail)
2903 		return;
2904 
2905 	if (adapter->num_tx_desc_avail == adapter->num_tx_desc)
2906 		return;
2907 
2908 	num_avail = adapter->num_tx_desc_avail;
2909 	first = adapter->next_tx_to_clean;
2910 
2911 	while (adapter->tx_dd_head != adapter->tx_dd_tail) {
2912 		struct e1000_tx_desc *tx_desc;
2913 		int dd_idx = adapter->tx_dd[adapter->tx_dd_head];
2914 
2915 		tx_desc = &adapter->tx_desc_base[dd_idx];
2916 		if (tx_desc->upper.fields.status & E1000_TXD_STAT_DD) {
2917 			EM_INC_TXDD_IDX(adapter->tx_dd_head);
2918 
2919 			if (++dd_idx == adapter->num_tx_desc)
2920 				dd_idx = 0;
2921 
2922 			while (first != dd_idx) {
2923 				logif(pkt_txclean);
2924 
2925 				num_avail++;
2926 
2927 				tx_buffer = &adapter->tx_buffer_area[first];
2928 				if (tx_buffer->m_head) {
2929 					ifp->if_opackets++;
2930 					bus_dmamap_unload(adapter->txtag,
2931 							  tx_buffer->map);
2932 					m_freem(tx_buffer->m_head);
2933 					tx_buffer->m_head = NULL;
2934 				}
2935 
2936 				if (++first == adapter->num_tx_desc)
2937 					first = 0;
2938 			}
2939 		} else {
2940 			break;
2941 		}
2942 	}
2943 	adapter->next_tx_to_clean = first;
2944 	adapter->num_tx_desc_avail = num_avail;
2945 
2946 	if (adapter->tx_dd_head == adapter->tx_dd_tail) {
2947 		adapter->tx_dd_head = 0;
2948 		adapter->tx_dd_tail = 0;
2949 	}
2950 
2951 	if (!EM_IS_OACTIVE(adapter)) {
2952 		ifq_clr_oactive(&ifp->if_snd);
2953 
2954 		/* All clean, turn off the timer */
2955 		if (adapter->num_tx_desc_avail == adapter->num_tx_desc)
2956 			ifp->if_timer = 0;
2957 	}
2958 }
2959 
2960 static void
2961 em_tx_collect(struct adapter *adapter)
2962 {
2963 	struct ifnet *ifp = &adapter->arpcom.ac_if;
2964 	struct em_buffer *tx_buffer;
2965 	int tdh, first, num_avail, dd_idx = -1;
2966 
2967 	if (adapter->num_tx_desc_avail == adapter->num_tx_desc)
2968 		return;
2969 
2970 	tdh = E1000_READ_REG(&adapter->hw, E1000_TDH(0));
2971 	if (tdh == adapter->next_tx_to_clean)
2972 		return;
2973 
2974 	if (adapter->tx_dd_head != adapter->tx_dd_tail)
2975 		dd_idx = adapter->tx_dd[adapter->tx_dd_head];
2976 
2977 	num_avail = adapter->num_tx_desc_avail;
2978 	first = adapter->next_tx_to_clean;
2979 
2980 	while (first != tdh) {
2981 		logif(pkt_txclean);
2982 
2983 		num_avail++;
2984 
2985 		tx_buffer = &adapter->tx_buffer_area[first];
2986 		if (tx_buffer->m_head) {
2987 			ifp->if_opackets++;
2988 			bus_dmamap_unload(adapter->txtag,
2989 					  tx_buffer->map);
2990 			m_freem(tx_buffer->m_head);
2991 			tx_buffer->m_head = NULL;
2992 		}
2993 
2994 		if (first == dd_idx) {
2995 			EM_INC_TXDD_IDX(adapter->tx_dd_head);
2996 			if (adapter->tx_dd_head == adapter->tx_dd_tail) {
2997 				adapter->tx_dd_head = 0;
2998 				adapter->tx_dd_tail = 0;
2999 				dd_idx = -1;
3000 			} else {
3001 				dd_idx = adapter->tx_dd[adapter->tx_dd_head];
3002 			}
3003 		}
3004 
3005 		if (++first == adapter->num_tx_desc)
3006 			first = 0;
3007 	}
3008 	adapter->next_tx_to_clean = first;
3009 	adapter->num_tx_desc_avail = num_avail;
3010 
3011 	if (!EM_IS_OACTIVE(adapter)) {
3012 		ifq_clr_oactive(&ifp->if_snd);
3013 
3014 		/* All clean, turn off the timer */
3015 		if (adapter->num_tx_desc_avail == adapter->num_tx_desc)
3016 			ifp->if_timer = 0;
3017 	}
3018 }
3019 
3020 /*
3021  * When Link is lost sometimes there is work still in the TX ring
3022  * which will result in a watchdog, rather than allow that do an
3023  * attempted cleanup and then reinit here.  Note that this has been
3024  * seens mostly with fiber adapters.
3025  */
3026 static void
3027 em_tx_purge(struct adapter *adapter)
3028 {
3029 	struct ifnet *ifp = &adapter->arpcom.ac_if;
3030 
3031 	if (!adapter->link_active && ifp->if_timer) {
3032 		em_tx_collect(adapter);
3033 		if (ifp->if_timer) {
3034 			if_printf(ifp, "Link lost, TX pending, reinit\n");
3035 			ifp->if_timer = 0;
3036 			em_init(adapter);
3037 		}
3038 	}
3039 }
3040 
3041 static int
3042 em_newbuf(struct adapter *adapter, int i, int init)
3043 {
3044 	struct mbuf *m;
3045 	bus_dma_segment_t seg;
3046 	bus_dmamap_t map;
3047 	struct em_buffer *rx_buffer;
3048 	int error, nseg;
3049 
3050 	m = m_getcl(init ? MB_WAIT : MB_DONTWAIT, MT_DATA, M_PKTHDR);
3051 	if (m == NULL) {
3052 		adapter->mbuf_cluster_failed++;
3053 		if (init) {
3054 			if_printf(&adapter->arpcom.ac_if,
3055 				  "Unable to allocate RX mbuf\n");
3056 		}
3057 		return (ENOBUFS);
3058 	}
3059 	m->m_len = m->m_pkthdr.len = MCLBYTES;
3060 
3061 	if (adapter->max_frame_size <= MCLBYTES - ETHER_ALIGN)
3062 		m_adj(m, ETHER_ALIGN);
3063 
3064 	error = bus_dmamap_load_mbuf_segment(adapter->rxtag,
3065 			adapter->rx_sparemap, m,
3066 			&seg, 1, &nseg, BUS_DMA_NOWAIT);
3067 	if (error) {
3068 		m_freem(m);
3069 		if (init) {
3070 			if_printf(&adapter->arpcom.ac_if,
3071 				  "Unable to load RX mbuf\n");
3072 		}
3073 		return (error);
3074 	}
3075 
3076 	rx_buffer = &adapter->rx_buffer_area[i];
3077 	if (rx_buffer->m_head != NULL)
3078 		bus_dmamap_unload(adapter->rxtag, rx_buffer->map);
3079 
3080 	map = rx_buffer->map;
3081 	rx_buffer->map = adapter->rx_sparemap;
3082 	adapter->rx_sparemap = map;
3083 
3084 	rx_buffer->m_head = m;
3085 
3086 	adapter->rx_desc_base[i].buffer_addr = htole64(seg.ds_addr);
3087 	return (0);
3088 }
3089 
3090 static int
3091 em_create_rx_ring(struct adapter *adapter)
3092 {
3093 	device_t dev = adapter->dev;
3094 	struct em_buffer *rx_buffer;
3095 	int i, error;
3096 
3097 	adapter->rx_buffer_area =
3098 		kmalloc(sizeof(struct em_buffer) * adapter->num_rx_desc,
3099 			M_DEVBUF, M_WAITOK | M_ZERO);
3100 
3101 	/*
3102 	 * Create DMA tag for rx buffers
3103 	 */
3104 	error = bus_dma_tag_create(adapter->parent_dtag, /* parent */
3105 			1, 0,			/* alignment, bounds */
3106 			BUS_SPACE_MAXADDR,	/* lowaddr */
3107 			BUS_SPACE_MAXADDR,	/* highaddr */
3108 			NULL, NULL,		/* filter, filterarg */
3109 			MCLBYTES,		/* maxsize */
3110 			1,			/* nsegments */
3111 			MCLBYTES,		/* maxsegsize */
3112 			BUS_DMA_WAITOK | BUS_DMA_ALLOCNOW, /* flags */
3113 			&adapter->rxtag);
3114 	if (error) {
3115 		device_printf(dev, "Unable to allocate RX DMA tag\n");
3116 		kfree(adapter->rx_buffer_area, M_DEVBUF);
3117 		adapter->rx_buffer_area = NULL;
3118 		return error;
3119 	}
3120 
3121 	/*
3122 	 * Create spare DMA map for rx buffers
3123 	 */
3124 	error = bus_dmamap_create(adapter->rxtag, BUS_DMA_WAITOK,
3125 				  &adapter->rx_sparemap);
3126 	if (error) {
3127 		device_printf(dev, "Unable to create spare RX DMA map\n");
3128 		bus_dma_tag_destroy(adapter->rxtag);
3129 		kfree(adapter->rx_buffer_area, M_DEVBUF);
3130 		adapter->rx_buffer_area = NULL;
3131 		return error;
3132 	}
3133 
3134 	/*
3135 	 * Create DMA maps for rx buffers
3136 	 */
3137 	for (i = 0; i < adapter->num_rx_desc; i++) {
3138 		rx_buffer = &adapter->rx_buffer_area[i];
3139 
3140 		error = bus_dmamap_create(adapter->rxtag, BUS_DMA_WAITOK,
3141 					  &rx_buffer->map);
3142 		if (error) {
3143 			device_printf(dev, "Unable to create RX DMA map\n");
3144 			em_destroy_rx_ring(adapter, i);
3145 			return error;
3146 		}
3147 	}
3148 	return (0);
3149 }
3150 
3151 static int
3152 em_init_rx_ring(struct adapter *adapter)
3153 {
3154 	int i, error;
3155 
3156 	/* Reset descriptor ring */
3157 	bzero(adapter->rx_desc_base,
3158 	    (sizeof(struct e1000_rx_desc)) * adapter->num_rx_desc);
3159 
3160 	/* Allocate new ones. */
3161 	for (i = 0; i < adapter->num_rx_desc; i++) {
3162 		error = em_newbuf(adapter, i, 1);
3163 		if (error)
3164 			return (error);
3165 	}
3166 
3167 	/* Setup our descriptor pointers */
3168 	adapter->next_rx_desc_to_check = 0;
3169 
3170 	return (0);
3171 }
3172 
3173 static void
3174 em_init_rx_unit(struct adapter *adapter)
3175 {
3176 	struct ifnet *ifp = &adapter->arpcom.ac_if;
3177 	uint64_t bus_addr;
3178 	uint32_t rctl;
3179 
3180 	/*
3181 	 * Make sure receives are disabled while setting
3182 	 * up the descriptor ring
3183 	 */
3184 	rctl = E1000_READ_REG(&adapter->hw, E1000_RCTL);
3185 	E1000_WRITE_REG(&adapter->hw, E1000_RCTL, rctl & ~E1000_RCTL_EN);
3186 
3187 	if (adapter->hw.mac.type >= e1000_82540) {
3188 		uint32_t itr;
3189 
3190 		/*
3191 		 * Set the interrupt throttling rate. Value is calculated
3192 		 * as ITR = 1 / (INT_THROTTLE_CEIL * 256ns)
3193 		 */
3194 		if (adapter->int_throttle_ceil)
3195 			itr = 1000000000 / 256 / adapter->int_throttle_ceil;
3196 		else
3197 			itr = 0;
3198 		em_set_itr(adapter, itr);
3199 	}
3200 
3201 	/* Disable accelerated ackknowledge */
3202 	if (adapter->hw.mac.type == e1000_82574) {
3203 		E1000_WRITE_REG(&adapter->hw,
3204 		    E1000_RFCTL, E1000_RFCTL_ACK_DIS);
3205 	}
3206 
3207 	/* Receive Checksum Offload for TCP and UDP */
3208 	if (ifp->if_capenable & IFCAP_RXCSUM) {
3209 		uint32_t rxcsum;
3210 
3211 		rxcsum = E1000_READ_REG(&adapter->hw, E1000_RXCSUM);
3212 		rxcsum |= (E1000_RXCSUM_IPOFL | E1000_RXCSUM_TUOFL);
3213 		E1000_WRITE_REG(&adapter->hw, E1000_RXCSUM, rxcsum);
3214 	}
3215 
3216 	/*
3217 	 * XXX TEMPORARY WORKAROUND: on some systems with 82573
3218 	 * long latencies are observed, like Lenovo X60. This
3219 	 * change eliminates the problem, but since having positive
3220 	 * values in RDTR is a known source of problems on other
3221 	 * platforms another solution is being sought.
3222 	 */
3223 	if (em_82573_workaround && adapter->hw.mac.type == e1000_82573) {
3224 		E1000_WRITE_REG(&adapter->hw, E1000_RADV, EM_RADV_82573);
3225 		E1000_WRITE_REG(&adapter->hw, E1000_RDTR, EM_RDTR_82573);
3226 	}
3227 
3228 	/*
3229 	 * Setup the Base and Length of the Rx Descriptor Ring
3230 	 */
3231 	bus_addr = adapter->rxdma.dma_paddr;
3232 	E1000_WRITE_REG(&adapter->hw, E1000_RDLEN(0),
3233 	    adapter->num_rx_desc * sizeof(struct e1000_rx_desc));
3234 	E1000_WRITE_REG(&adapter->hw, E1000_RDBAH(0),
3235 	    (uint32_t)(bus_addr >> 32));
3236 	E1000_WRITE_REG(&adapter->hw, E1000_RDBAL(0),
3237 	    (uint32_t)bus_addr);
3238 
3239 	/*
3240 	 * Setup the HW Rx Head and Tail Descriptor Pointers
3241 	 */
3242 	E1000_WRITE_REG(&adapter->hw, E1000_RDH(0), 0);
3243 	E1000_WRITE_REG(&adapter->hw, E1000_RDT(0), adapter->num_rx_desc - 1);
3244 
3245 	/* Set early receive threshold on appropriate hw */
3246 	if (((adapter->hw.mac.type == e1000_ich9lan) ||
3247 	    (adapter->hw.mac.type == e1000_pch2lan) ||
3248 	    (adapter->hw.mac.type == e1000_ich10lan)) &&
3249 	    (ifp->if_mtu > ETHERMTU)) {
3250 		uint32_t rxdctl;
3251 
3252 		rxdctl = E1000_READ_REG(&adapter->hw, E1000_RXDCTL(0));
3253 		E1000_WRITE_REG(&adapter->hw, E1000_RXDCTL(0), rxdctl | 3);
3254 		E1000_WRITE_REG(&adapter->hw, E1000_ERT, 0x100 | (1 << 13));
3255 	}
3256 
3257 	if (adapter->hw.mac.type == e1000_pch2lan) {
3258 		if (ifp->if_mtu > ETHERMTU)
3259 			e1000_lv_jumbo_workaround_ich8lan(&adapter->hw, TRUE);
3260 		else
3261 			e1000_lv_jumbo_workaround_ich8lan(&adapter->hw, FALSE);
3262 	}
3263 
3264 	/* Setup the Receive Control Register */
3265 	rctl &= ~(3 << E1000_RCTL_MO_SHIFT);
3266 	rctl |= E1000_RCTL_EN | E1000_RCTL_BAM | E1000_RCTL_LBM_NO |
3267 		E1000_RCTL_RDMTS_HALF |
3268 		(adapter->hw.mac.mc_filter_type << E1000_RCTL_MO_SHIFT);
3269 
3270 	/* Make sure VLAN Filters are off */
3271 	rctl &= ~E1000_RCTL_VFE;
3272 
3273 	if (e1000_tbi_sbp_enabled_82543(&adapter->hw))
3274 		rctl |= E1000_RCTL_SBP;
3275 	else
3276 		rctl &= ~E1000_RCTL_SBP;
3277 
3278 	switch (adapter->rx_buffer_len) {
3279 	default:
3280 	case 2048:
3281 		rctl |= E1000_RCTL_SZ_2048;
3282 		break;
3283 
3284 	case 4096:
3285 		rctl |= E1000_RCTL_SZ_4096 |
3286 		    E1000_RCTL_BSEX | E1000_RCTL_LPE;
3287 		break;
3288 
3289 	case 8192:
3290 		rctl |= E1000_RCTL_SZ_8192 |
3291 		    E1000_RCTL_BSEX | E1000_RCTL_LPE;
3292 		break;
3293 
3294 	case 16384:
3295 		rctl |= E1000_RCTL_SZ_16384 |
3296 		    E1000_RCTL_BSEX | E1000_RCTL_LPE;
3297 		break;
3298 	}
3299 
3300 	if (ifp->if_mtu > ETHERMTU)
3301 		rctl |= E1000_RCTL_LPE;
3302 	else
3303 		rctl &= ~E1000_RCTL_LPE;
3304 
3305 	/* Enable Receives */
3306 	E1000_WRITE_REG(&adapter->hw, E1000_RCTL, rctl);
3307 }
3308 
3309 static void
3310 em_destroy_rx_ring(struct adapter *adapter, int ndesc)
3311 {
3312 	struct em_buffer *rx_buffer;
3313 	int i;
3314 
3315 	if (adapter->rx_buffer_area == NULL)
3316 		return;
3317 
3318 	for (i = 0; i < ndesc; i++) {
3319 		rx_buffer = &adapter->rx_buffer_area[i];
3320 
3321 		KKASSERT(rx_buffer->m_head == NULL);
3322 		bus_dmamap_destroy(adapter->rxtag, rx_buffer->map);
3323 	}
3324 	bus_dmamap_destroy(adapter->rxtag, adapter->rx_sparemap);
3325 	bus_dma_tag_destroy(adapter->rxtag);
3326 
3327 	kfree(adapter->rx_buffer_area, M_DEVBUF);
3328 	adapter->rx_buffer_area = NULL;
3329 }
3330 
3331 static void
3332 em_rxeof(struct adapter *adapter, int count)
3333 {
3334 	struct ifnet *ifp = &adapter->arpcom.ac_if;
3335 	uint8_t status, accept_frame = 0, eop = 0;
3336 	uint16_t len, desc_len, prev_len_adj;
3337 	struct e1000_rx_desc *current_desc;
3338 	struct mbuf *mp;
3339 	int i;
3340 
3341 	i = adapter->next_rx_desc_to_check;
3342 	current_desc = &adapter->rx_desc_base[i];
3343 
3344 	if (!(current_desc->status & E1000_RXD_STAT_DD))
3345 		return;
3346 
3347 	while ((current_desc->status & E1000_RXD_STAT_DD) && count != 0) {
3348 		struct mbuf *m = NULL;
3349 
3350 		logif(pkt_receive);
3351 
3352 		mp = adapter->rx_buffer_area[i].m_head;
3353 
3354 		/*
3355 		 * Can't defer bus_dmamap_sync(9) because TBI_ACCEPT
3356 		 * needs to access the last received byte in the mbuf.
3357 		 */
3358 		bus_dmamap_sync(adapter->rxtag, adapter->rx_buffer_area[i].map,
3359 				BUS_DMASYNC_POSTREAD);
3360 
3361 		accept_frame = 1;
3362 		prev_len_adj = 0;
3363 		desc_len = le16toh(current_desc->length);
3364 		status = current_desc->status;
3365 		if (status & E1000_RXD_STAT_EOP) {
3366 			count--;
3367 			eop = 1;
3368 			if (desc_len < ETHER_CRC_LEN) {
3369 				len = 0;
3370 				prev_len_adj = ETHER_CRC_LEN - desc_len;
3371 			} else {
3372 				len = desc_len - ETHER_CRC_LEN;
3373 			}
3374 		} else {
3375 			eop = 0;
3376 			len = desc_len;
3377 		}
3378 
3379 		if (current_desc->errors & E1000_RXD_ERR_FRAME_ERR_MASK) {
3380 			uint8_t	last_byte;
3381 			uint32_t pkt_len = desc_len;
3382 
3383 			if (adapter->fmp != NULL)
3384 				pkt_len += adapter->fmp->m_pkthdr.len;
3385 
3386 			last_byte = *(mtod(mp, caddr_t) + desc_len - 1);
3387 			if (TBI_ACCEPT(&adapter->hw, status,
3388 			    current_desc->errors, pkt_len, last_byte,
3389 			    adapter->min_frame_size, adapter->max_frame_size)) {
3390 				e1000_tbi_adjust_stats_82543(&adapter->hw,
3391 				    &adapter->stats, pkt_len,
3392 				    adapter->hw.mac.addr,
3393 				    adapter->max_frame_size);
3394 				if (len > 0)
3395 					len--;
3396 			} else {
3397 				accept_frame = 0;
3398 			}
3399 		}
3400 
3401 		if (accept_frame) {
3402 			if (em_newbuf(adapter, i, 0) != 0) {
3403 				ifp->if_iqdrops++;
3404 				goto discard;
3405 			}
3406 
3407 			/* Assign correct length to the current fragment */
3408 			mp->m_len = len;
3409 
3410 			if (adapter->fmp == NULL) {
3411 				mp->m_pkthdr.len = len;
3412 				adapter->fmp = mp; /* Store the first mbuf */
3413 				adapter->lmp = mp;
3414 			} else {
3415 				/*
3416 				 * Chain mbuf's together
3417 				 */
3418 
3419 				/*
3420 				 * Adjust length of previous mbuf in chain if
3421 				 * we received less than 4 bytes in the last
3422 				 * descriptor.
3423 				 */
3424 				if (prev_len_adj > 0) {
3425 					adapter->lmp->m_len -= prev_len_adj;
3426 					adapter->fmp->m_pkthdr.len -=
3427 					    prev_len_adj;
3428 				}
3429 				adapter->lmp->m_next = mp;
3430 				adapter->lmp = adapter->lmp->m_next;
3431 				adapter->fmp->m_pkthdr.len += len;
3432 			}
3433 
3434 			if (eop) {
3435 				adapter->fmp->m_pkthdr.rcvif = ifp;
3436 				ifp->if_ipackets++;
3437 
3438 				if (ifp->if_capenable & IFCAP_RXCSUM) {
3439 					em_rxcsum(adapter, current_desc,
3440 						  adapter->fmp);
3441 				}
3442 
3443 				if (status & E1000_RXD_STAT_VP) {
3444 					adapter->fmp->m_pkthdr.ether_vlantag =
3445 					    (le16toh(current_desc->special) &
3446 					    E1000_RXD_SPC_VLAN_MASK);
3447 					adapter->fmp->m_flags |= M_VLANTAG;
3448 				}
3449 				m = adapter->fmp;
3450 				adapter->fmp = NULL;
3451 				adapter->lmp = NULL;
3452 			}
3453 		} else {
3454 			ifp->if_ierrors++;
3455 discard:
3456 #ifdef foo
3457 			/* Reuse loaded DMA map and just update mbuf chain */
3458 			mp = adapter->rx_buffer_area[i].m_head;
3459 			mp->m_len = mp->m_pkthdr.len = MCLBYTES;
3460 			mp->m_data = mp->m_ext.ext_buf;
3461 			mp->m_next = NULL;
3462 			if (adapter->max_frame_size <= (MCLBYTES - ETHER_ALIGN))
3463 				m_adj(mp, ETHER_ALIGN);
3464 #endif
3465 			if (adapter->fmp != NULL) {
3466 				m_freem(adapter->fmp);
3467 				adapter->fmp = NULL;
3468 				adapter->lmp = NULL;
3469 			}
3470 			m = NULL;
3471 		}
3472 
3473 		/* Zero out the receive descriptors status. */
3474 		current_desc->status = 0;
3475 
3476 		if (m != NULL)
3477 			ifp->if_input(ifp, m);
3478 
3479 		/* Advance our pointers to the next descriptor. */
3480 		if (++i == adapter->num_rx_desc)
3481 			i = 0;
3482 		current_desc = &adapter->rx_desc_base[i];
3483 	}
3484 	adapter->next_rx_desc_to_check = i;
3485 
3486 	/* Advance the E1000's Receive Queue #0  "Tail Pointer". */
3487 	if (--i < 0)
3488 		i = adapter->num_rx_desc - 1;
3489 	E1000_WRITE_REG(&adapter->hw, E1000_RDT(0), i);
3490 }
3491 
3492 static void
3493 em_rxcsum(struct adapter *adapter, struct e1000_rx_desc *rx_desc,
3494 	  struct mbuf *mp)
3495 {
3496 	/* 82543 or newer only */
3497 	if (adapter->hw.mac.type < e1000_82543 ||
3498 	    /* Ignore Checksum bit is set */
3499 	    (rx_desc->status & E1000_RXD_STAT_IXSM))
3500 		return;
3501 
3502 	if ((rx_desc->status & E1000_RXD_STAT_IPCS) &&
3503 	    !(rx_desc->errors & E1000_RXD_ERR_IPE)) {
3504 		/* IP Checksum Good */
3505 		mp->m_pkthdr.csum_flags |= CSUM_IP_CHECKED | CSUM_IP_VALID;
3506 	}
3507 
3508 	if ((rx_desc->status & E1000_RXD_STAT_TCPCS) &&
3509 	    !(rx_desc->errors & E1000_RXD_ERR_TCPE)) {
3510 		mp->m_pkthdr.csum_flags |= CSUM_DATA_VALID |
3511 					   CSUM_PSEUDO_HDR |
3512 					   CSUM_FRAG_NOT_CHECKED;
3513 		mp->m_pkthdr.csum_data = htons(0xffff);
3514 	}
3515 }
3516 
3517 static void
3518 em_enable_intr(struct adapter *adapter)
3519 {
3520 	uint32_t ims_mask = IMS_ENABLE_MASK;
3521 
3522 	lwkt_serialize_handler_enable(adapter->arpcom.ac_if.if_serializer);
3523 
3524 #if 0
3525 	/* XXX MSIX */
3526 	if (adapter->hw.mac.type == e1000_82574) {
3527 		E1000_WRITE_REG(&adapter->hw, EM_EIAC, EM_MSIX_MASK);
3528 		ims_mask |= EM_MSIX_MASK;
3529         }
3530 #endif
3531 	E1000_WRITE_REG(&adapter->hw, E1000_IMS, ims_mask);
3532 }
3533 
3534 static void
3535 em_disable_intr(struct adapter *adapter)
3536 {
3537 	uint32_t clear = 0xffffffff;
3538 
3539 	/*
3540 	 * The first version of 82542 had an errata where when link was forced
3541 	 * it would stay up even up even if the cable was disconnected.
3542 	 * Sequence errors were used to detect the disconnect and then the
3543 	 * driver would unforce the link.  This code in the in the ISR.  For
3544 	 * this to work correctly the Sequence error interrupt had to be
3545 	 * enabled all the time.
3546 	 */
3547 	if (adapter->hw.mac.type == e1000_82542 &&
3548 	    adapter->hw.revision_id == E1000_REVISION_2)
3549 		clear &= ~E1000_ICR_RXSEQ;
3550 	else if (adapter->hw.mac.type == e1000_82574)
3551 		E1000_WRITE_REG(&adapter->hw, EM_EIAC, 0);
3552 
3553 	E1000_WRITE_REG(&adapter->hw, E1000_IMC, clear);
3554 
3555 	adapter->npoll.ifpc_stcount = 0;
3556 
3557 	lwkt_serialize_handler_disable(adapter->arpcom.ac_if.if_serializer);
3558 }
3559 
3560 /*
3561  * Bit of a misnomer, what this really means is
3562  * to enable OS management of the system... aka
3563  * to disable special hardware management features
3564  */
3565 static void
3566 em_get_mgmt(struct adapter *adapter)
3567 {
3568 	/* A shared code workaround */
3569 #define E1000_82542_MANC2H E1000_MANC2H
3570 	if (adapter->flags & EM_FLAG_HAS_MGMT) {
3571 		int manc2h = E1000_READ_REG(&adapter->hw, E1000_MANC2H);
3572 		int manc = E1000_READ_REG(&adapter->hw, E1000_MANC);
3573 
3574 		/* disable hardware interception of ARP */
3575 		manc &= ~(E1000_MANC_ARP_EN);
3576 
3577                 /* enable receiving management packets to the host */
3578                 if (adapter->hw.mac.type >= e1000_82571) {
3579 			manc |= E1000_MANC_EN_MNG2HOST;
3580 #define E1000_MNG2HOST_PORT_623 (1 << 5)
3581 #define E1000_MNG2HOST_PORT_664 (1 << 6)
3582 			manc2h |= E1000_MNG2HOST_PORT_623;
3583 			manc2h |= E1000_MNG2HOST_PORT_664;
3584 			E1000_WRITE_REG(&adapter->hw, E1000_MANC2H, manc2h);
3585 		}
3586 
3587 		E1000_WRITE_REG(&adapter->hw, E1000_MANC, manc);
3588 	}
3589 }
3590 
3591 /*
3592  * Give control back to hardware management
3593  * controller if there is one.
3594  */
3595 static void
3596 em_rel_mgmt(struct adapter *adapter)
3597 {
3598 	if (adapter->flags & EM_FLAG_HAS_MGMT) {
3599 		int manc = E1000_READ_REG(&adapter->hw, E1000_MANC);
3600 
3601 		/* re-enable hardware interception of ARP */
3602 		manc |= E1000_MANC_ARP_EN;
3603 
3604 		if (adapter->hw.mac.type >= e1000_82571)
3605 			manc &= ~E1000_MANC_EN_MNG2HOST;
3606 
3607 		E1000_WRITE_REG(&adapter->hw, E1000_MANC, manc);
3608 	}
3609 }
3610 
3611 /*
3612  * em_get_hw_control() sets {CTRL_EXT|FWSM}:DRV_LOAD bit.
3613  * For ASF and Pass Through versions of f/w this means that
3614  * the driver is loaded.  For AMT version (only with 82573)
3615  * of the f/w this means that the network i/f is open.
3616  */
3617 static void
3618 em_get_hw_control(struct adapter *adapter)
3619 {
3620 	/* Let firmware know the driver has taken over */
3621 	if (adapter->hw.mac.type == e1000_82573) {
3622 		uint32_t swsm;
3623 
3624 		swsm = E1000_READ_REG(&adapter->hw, E1000_SWSM);
3625 		E1000_WRITE_REG(&adapter->hw, E1000_SWSM,
3626 		    swsm | E1000_SWSM_DRV_LOAD);
3627 	} else {
3628 		uint32_t ctrl_ext;
3629 
3630 		ctrl_ext = E1000_READ_REG(&adapter->hw, E1000_CTRL_EXT);
3631 		E1000_WRITE_REG(&adapter->hw, E1000_CTRL_EXT,
3632 		    ctrl_ext | E1000_CTRL_EXT_DRV_LOAD);
3633 	}
3634 	adapter->flags |= EM_FLAG_HW_CTRL;
3635 }
3636 
3637 /*
3638  * em_rel_hw_control() resets {CTRL_EXT|FWSM}:DRV_LOAD bit.
3639  * For ASF and Pass Through versions of f/w this means that the
3640  * driver is no longer loaded.  For AMT version (only with 82573)
3641  * of the f/w this means that the network i/f is closed.
3642  */
3643 static void
3644 em_rel_hw_control(struct adapter *adapter)
3645 {
3646 	if ((adapter->flags & EM_FLAG_HW_CTRL) == 0)
3647 		return;
3648 	adapter->flags &= ~EM_FLAG_HW_CTRL;
3649 
3650 	/* Let firmware taken over control of h/w */
3651 	if (adapter->hw.mac.type == e1000_82573) {
3652 		uint32_t swsm;
3653 
3654 		swsm = E1000_READ_REG(&adapter->hw, E1000_SWSM);
3655 		E1000_WRITE_REG(&adapter->hw, E1000_SWSM,
3656 		    swsm & ~E1000_SWSM_DRV_LOAD);
3657 	} else {
3658 		uint32_t ctrl_ext;
3659 
3660 		ctrl_ext = E1000_READ_REG(&adapter->hw, E1000_CTRL_EXT);
3661 		E1000_WRITE_REG(&adapter->hw, E1000_CTRL_EXT,
3662 		    ctrl_ext & ~E1000_CTRL_EXT_DRV_LOAD);
3663 	}
3664 }
3665 
3666 static int
3667 em_is_valid_eaddr(const uint8_t *addr)
3668 {
3669 	char zero_addr[ETHER_ADDR_LEN] = { 0, 0, 0, 0, 0, 0 };
3670 
3671 	if ((addr[0] & 1) || !bcmp(addr, zero_addr, ETHER_ADDR_LEN))
3672 		return (FALSE);
3673 
3674 	return (TRUE);
3675 }
3676 
3677 /*
3678  * Enable PCI Wake On Lan capability
3679  */
3680 void
3681 em_enable_wol(device_t dev)
3682 {
3683 	uint16_t cap, status;
3684 	uint8_t id;
3685 
3686 	/* First find the capabilities pointer*/
3687 	cap = pci_read_config(dev, PCIR_CAP_PTR, 2);
3688 
3689 	/* Read the PM Capabilities */
3690 	id = pci_read_config(dev, cap, 1);
3691 	if (id != PCIY_PMG)     /* Something wrong */
3692 		return;
3693 
3694 	/*
3695 	 * OK, we have the power capabilities,
3696 	 * so now get the status register
3697 	 */
3698 	cap += PCIR_POWER_STATUS;
3699 	status = pci_read_config(dev, cap, 2);
3700 	status |= PCIM_PSTAT_PME | PCIM_PSTAT_PMEENABLE;
3701 	pci_write_config(dev, cap, status, 2);
3702 }
3703 
3704 
3705 /*
3706  * 82544 Coexistence issue workaround.
3707  *    There are 2 issues.
3708  *       1. Transmit Hang issue.
3709  *    To detect this issue, following equation can be used...
3710  *	  SIZE[3:0] + ADDR[2:0] = SUM[3:0].
3711  *	  If SUM[3:0] is in between 1 to 4, we will have this issue.
3712  *
3713  *       2. DAC issue.
3714  *    To detect this issue, following equation can be used...
3715  *	  SIZE[3:0] + ADDR[2:0] = SUM[3:0].
3716  *	  If SUM[3:0] is in between 9 to c, we will have this issue.
3717  *
3718  *    WORKAROUND:
3719  *	  Make sure we do not have ending address
3720  *	  as 1,2,3,4(Hang) or 9,a,b,c (DAC)
3721  */
3722 static uint32_t
3723 em_82544_fill_desc(bus_addr_t address, uint32_t length, PDESC_ARRAY desc_array)
3724 {
3725 	uint32_t safe_terminator;
3726 
3727 	/*
3728 	 * Since issue is sensitive to length and address.
3729 	 * Let us first check the address...
3730 	 */
3731 	if (length <= 4) {
3732 		desc_array->descriptor[0].address = address;
3733 		desc_array->descriptor[0].length = length;
3734 		desc_array->elements = 1;
3735 		return (desc_array->elements);
3736 	}
3737 
3738 	safe_terminator =
3739 	(uint32_t)((((uint32_t)address & 0x7) + (length & 0xF)) & 0xF);
3740 
3741 	/* If it does not fall between 0x1 to 0x4 and 0x9 to 0xC then return */
3742 	if (safe_terminator == 0 ||
3743 	    (safe_terminator > 4 && safe_terminator < 9) ||
3744 	    (safe_terminator > 0xC && safe_terminator <= 0xF)) {
3745 		desc_array->descriptor[0].address = address;
3746 		desc_array->descriptor[0].length = length;
3747 		desc_array->elements = 1;
3748 		return (desc_array->elements);
3749 	}
3750 
3751 	desc_array->descriptor[0].address = address;
3752 	desc_array->descriptor[0].length = length - 4;
3753 	desc_array->descriptor[1].address = address + (length - 4);
3754 	desc_array->descriptor[1].length = 4;
3755 	desc_array->elements = 2;
3756 	return (desc_array->elements);
3757 }
3758 
3759 static void
3760 em_update_stats(struct adapter *adapter)
3761 {
3762 	struct ifnet *ifp = &adapter->arpcom.ac_if;
3763 
3764 	if (adapter->hw.phy.media_type == e1000_media_type_copper ||
3765 	    (E1000_READ_REG(&adapter->hw, E1000_STATUS) & E1000_STATUS_LU)) {
3766 		adapter->stats.symerrs +=
3767 			E1000_READ_REG(&adapter->hw, E1000_SYMERRS);
3768 		adapter->stats.sec += E1000_READ_REG(&adapter->hw, E1000_SEC);
3769 	}
3770 	adapter->stats.crcerrs += E1000_READ_REG(&adapter->hw, E1000_CRCERRS);
3771 	adapter->stats.mpc += E1000_READ_REG(&adapter->hw, E1000_MPC);
3772 	adapter->stats.scc += E1000_READ_REG(&adapter->hw, E1000_SCC);
3773 	adapter->stats.ecol += E1000_READ_REG(&adapter->hw, E1000_ECOL);
3774 
3775 	adapter->stats.mcc += E1000_READ_REG(&adapter->hw, E1000_MCC);
3776 	adapter->stats.latecol += E1000_READ_REG(&adapter->hw, E1000_LATECOL);
3777 	adapter->stats.colc += E1000_READ_REG(&adapter->hw, E1000_COLC);
3778 	adapter->stats.dc += E1000_READ_REG(&adapter->hw, E1000_DC);
3779 	adapter->stats.rlec += E1000_READ_REG(&adapter->hw, E1000_RLEC);
3780 	adapter->stats.xonrxc += E1000_READ_REG(&adapter->hw, E1000_XONRXC);
3781 	adapter->stats.xontxc += E1000_READ_REG(&adapter->hw, E1000_XONTXC);
3782 	adapter->stats.xoffrxc += E1000_READ_REG(&adapter->hw, E1000_XOFFRXC);
3783 	adapter->stats.xofftxc += E1000_READ_REG(&adapter->hw, E1000_XOFFTXC);
3784 	adapter->stats.fcruc += E1000_READ_REG(&adapter->hw, E1000_FCRUC);
3785 	adapter->stats.prc64 += E1000_READ_REG(&adapter->hw, E1000_PRC64);
3786 	adapter->stats.prc127 += E1000_READ_REG(&adapter->hw, E1000_PRC127);
3787 	adapter->stats.prc255 += E1000_READ_REG(&adapter->hw, E1000_PRC255);
3788 	adapter->stats.prc511 += E1000_READ_REG(&adapter->hw, E1000_PRC511);
3789 	adapter->stats.prc1023 += E1000_READ_REG(&adapter->hw, E1000_PRC1023);
3790 	adapter->stats.prc1522 += E1000_READ_REG(&adapter->hw, E1000_PRC1522);
3791 	adapter->stats.gprc += E1000_READ_REG(&adapter->hw, E1000_GPRC);
3792 	adapter->stats.bprc += E1000_READ_REG(&adapter->hw, E1000_BPRC);
3793 	adapter->stats.mprc += E1000_READ_REG(&adapter->hw, E1000_MPRC);
3794 	adapter->stats.gptc += E1000_READ_REG(&adapter->hw, E1000_GPTC);
3795 
3796 	/* For the 64-bit byte counters the low dword must be read first. */
3797 	/* Both registers clear on the read of the high dword */
3798 
3799 	adapter->stats.gorc += E1000_READ_REG(&adapter->hw, E1000_GORCH);
3800 	adapter->stats.gotc += E1000_READ_REG(&adapter->hw, E1000_GOTCH);
3801 
3802 	adapter->stats.rnbc += E1000_READ_REG(&adapter->hw, E1000_RNBC);
3803 	adapter->stats.ruc += E1000_READ_REG(&adapter->hw, E1000_RUC);
3804 	adapter->stats.rfc += E1000_READ_REG(&adapter->hw, E1000_RFC);
3805 	adapter->stats.roc += E1000_READ_REG(&adapter->hw, E1000_ROC);
3806 	adapter->stats.rjc += E1000_READ_REG(&adapter->hw, E1000_RJC);
3807 
3808 	adapter->stats.tor += E1000_READ_REG(&adapter->hw, E1000_TORH);
3809 	adapter->stats.tot += E1000_READ_REG(&adapter->hw, E1000_TOTH);
3810 
3811 	adapter->stats.tpr += E1000_READ_REG(&adapter->hw, E1000_TPR);
3812 	adapter->stats.tpt += E1000_READ_REG(&adapter->hw, E1000_TPT);
3813 	adapter->stats.ptc64 += E1000_READ_REG(&adapter->hw, E1000_PTC64);
3814 	adapter->stats.ptc127 += E1000_READ_REG(&adapter->hw, E1000_PTC127);
3815 	adapter->stats.ptc255 += E1000_READ_REG(&adapter->hw, E1000_PTC255);
3816 	adapter->stats.ptc511 += E1000_READ_REG(&adapter->hw, E1000_PTC511);
3817 	adapter->stats.ptc1023 += E1000_READ_REG(&adapter->hw, E1000_PTC1023);
3818 	adapter->stats.ptc1522 += E1000_READ_REG(&adapter->hw, E1000_PTC1522);
3819 	adapter->stats.mptc += E1000_READ_REG(&adapter->hw, E1000_MPTC);
3820 	adapter->stats.bptc += E1000_READ_REG(&adapter->hw, E1000_BPTC);
3821 
3822 	if (adapter->hw.mac.type >= e1000_82543) {
3823 		adapter->stats.algnerrc +=
3824 		E1000_READ_REG(&adapter->hw, E1000_ALGNERRC);
3825 		adapter->stats.rxerrc +=
3826 		E1000_READ_REG(&adapter->hw, E1000_RXERRC);
3827 		adapter->stats.tncrs +=
3828 		E1000_READ_REG(&adapter->hw, E1000_TNCRS);
3829 		adapter->stats.cexterr +=
3830 		E1000_READ_REG(&adapter->hw, E1000_CEXTERR);
3831 		adapter->stats.tsctc +=
3832 		E1000_READ_REG(&adapter->hw, E1000_TSCTC);
3833 		adapter->stats.tsctfc +=
3834 		E1000_READ_REG(&adapter->hw, E1000_TSCTFC);
3835 	}
3836 
3837 	ifp->if_collisions = adapter->stats.colc;
3838 
3839 	/* Rx Errors */
3840 	ifp->if_ierrors =
3841 	    adapter->dropped_pkts + adapter->stats.rxerrc +
3842 	    adapter->stats.crcerrs + adapter->stats.algnerrc +
3843 	    adapter->stats.ruc + adapter->stats.roc +
3844 	    adapter->stats.mpc + adapter->stats.cexterr;
3845 
3846 	/* Tx Errors */
3847 	ifp->if_oerrors =
3848 	    adapter->stats.ecol + adapter->stats.latecol +
3849 	    adapter->watchdog_events;
3850 }
3851 
3852 static void
3853 em_print_debug_info(struct adapter *adapter)
3854 {
3855 	device_t dev = adapter->dev;
3856 	uint8_t *hw_addr = adapter->hw.hw_addr;
3857 
3858 	device_printf(dev, "Adapter hardware address = %p \n", hw_addr);
3859 	device_printf(dev, "CTRL = 0x%x RCTL = 0x%x \n",
3860 	    E1000_READ_REG(&adapter->hw, E1000_CTRL),
3861 	    E1000_READ_REG(&adapter->hw, E1000_RCTL));
3862 	device_printf(dev, "Packet buffer = Tx=%dk Rx=%dk \n",
3863 	    ((E1000_READ_REG(&adapter->hw, E1000_PBA) & 0xffff0000) >> 16),\
3864 	    (E1000_READ_REG(&adapter->hw, E1000_PBA) & 0xffff) );
3865 	device_printf(dev, "Flow control watermarks high = %d low = %d\n",
3866 	    adapter->hw.fc.high_water,
3867 	    adapter->hw.fc.low_water);
3868 	device_printf(dev, "tx_int_delay = %d, tx_abs_int_delay = %d\n",
3869 	    E1000_READ_REG(&adapter->hw, E1000_TIDV),
3870 	    E1000_READ_REG(&adapter->hw, E1000_TADV));
3871 	device_printf(dev, "rx_int_delay = %d, rx_abs_int_delay = %d\n",
3872 	    E1000_READ_REG(&adapter->hw, E1000_RDTR),
3873 	    E1000_READ_REG(&adapter->hw, E1000_RADV));
3874 	device_printf(dev, "fifo workaround = %lld, fifo_reset_count = %lld\n",
3875 	    (long long)adapter->tx_fifo_wrk_cnt,
3876 	    (long long)adapter->tx_fifo_reset_cnt);
3877 	device_printf(dev, "hw tdh = %d, hw tdt = %d\n",
3878 	    E1000_READ_REG(&adapter->hw, E1000_TDH(0)),
3879 	    E1000_READ_REG(&adapter->hw, E1000_TDT(0)));
3880 	device_printf(dev, "hw rdh = %d, hw rdt = %d\n",
3881 	    E1000_READ_REG(&adapter->hw, E1000_RDH(0)),
3882 	    E1000_READ_REG(&adapter->hw, E1000_RDT(0)));
3883 	device_printf(dev, "Num Tx descriptors avail = %d\n",
3884 	    adapter->num_tx_desc_avail);
3885 	device_printf(dev, "Tx Descriptors not avail1 = %ld\n",
3886 	    adapter->no_tx_desc_avail1);
3887 	device_printf(dev, "Tx Descriptors not avail2 = %ld\n",
3888 	    adapter->no_tx_desc_avail2);
3889 	device_printf(dev, "Std mbuf failed = %ld\n",
3890 	    adapter->mbuf_alloc_failed);
3891 	device_printf(dev, "Std mbuf cluster failed = %ld\n",
3892 	    adapter->mbuf_cluster_failed);
3893 	device_printf(dev, "Driver dropped packets = %ld\n",
3894 	    adapter->dropped_pkts);
3895 	device_printf(dev, "Driver tx dma failure in encap = %ld\n",
3896 	    adapter->no_tx_dma_setup);
3897 }
3898 
3899 static void
3900 em_print_hw_stats(struct adapter *adapter)
3901 {
3902 	device_t dev = adapter->dev;
3903 
3904 	device_printf(dev, "Excessive collisions = %lld\n",
3905 	    (long long)adapter->stats.ecol);
3906 #if (DEBUG_HW > 0)  /* Dont output these errors normally */
3907 	device_printf(dev, "Symbol errors = %lld\n",
3908 	    (long long)adapter->stats.symerrs);
3909 #endif
3910 	device_printf(dev, "Sequence errors = %lld\n",
3911 	    (long long)adapter->stats.sec);
3912 	device_printf(dev, "Defer count = %lld\n",
3913 	    (long long)adapter->stats.dc);
3914 	device_printf(dev, "Missed Packets = %lld\n",
3915 	    (long long)adapter->stats.mpc);
3916 	device_printf(dev, "Receive No Buffers = %lld\n",
3917 	    (long long)adapter->stats.rnbc);
3918 	/* RLEC is inaccurate on some hardware, calculate our own. */
3919 	device_printf(dev, "Receive Length Errors = %lld\n",
3920 	    ((long long)adapter->stats.roc + (long long)adapter->stats.ruc));
3921 	device_printf(dev, "Receive errors = %lld\n",
3922 	    (long long)adapter->stats.rxerrc);
3923 	device_printf(dev, "Crc errors = %lld\n",
3924 	    (long long)adapter->stats.crcerrs);
3925 	device_printf(dev, "Alignment errors = %lld\n",
3926 	    (long long)adapter->stats.algnerrc);
3927 	device_printf(dev, "Collision/Carrier extension errors = %lld\n",
3928 	    (long long)adapter->stats.cexterr);
3929 	device_printf(dev, "RX overruns = %ld\n", adapter->rx_overruns);
3930 	device_printf(dev, "watchdog timeouts = %ld\n",
3931 	    adapter->watchdog_events);
3932 	device_printf(dev, "XON Rcvd = %lld\n",
3933 	    (long long)adapter->stats.xonrxc);
3934 	device_printf(dev, "XON Xmtd = %lld\n",
3935 	    (long long)adapter->stats.xontxc);
3936 	device_printf(dev, "XOFF Rcvd = %lld\n",
3937 	    (long long)adapter->stats.xoffrxc);
3938 	device_printf(dev, "XOFF Xmtd = %lld\n",
3939 	    (long long)adapter->stats.xofftxc);
3940 	device_printf(dev, "Good Packets Rcvd = %lld\n",
3941 	    (long long)adapter->stats.gprc);
3942 	device_printf(dev, "Good Packets Xmtd = %lld\n",
3943 	    (long long)adapter->stats.gptc);
3944 }
3945 
3946 static void
3947 em_print_nvm_info(struct adapter *adapter)
3948 {
3949 	uint16_t eeprom_data;
3950 	int i, j, row = 0;
3951 
3952 	/* Its a bit crude, but it gets the job done */
3953 	kprintf("\nInterface EEPROM Dump:\n");
3954 	kprintf("Offset\n0x0000  ");
3955 	for (i = 0, j = 0; i < 32; i++, j++) {
3956 		if (j == 8) { /* Make the offset block */
3957 			j = 0; ++row;
3958 			kprintf("\n0x00%x0  ",row);
3959 		}
3960 		e1000_read_nvm(&adapter->hw, i, 1, &eeprom_data);
3961 		kprintf("%04x ", eeprom_data);
3962 	}
3963 	kprintf("\n");
3964 }
3965 
3966 static int
3967 em_sysctl_debug_info(SYSCTL_HANDLER_ARGS)
3968 {
3969 	struct adapter *adapter;
3970 	struct ifnet *ifp;
3971 	int error, result;
3972 
3973 	result = -1;
3974 	error = sysctl_handle_int(oidp, &result, 0, req);
3975 	if (error || !req->newptr)
3976 		return (error);
3977 
3978 	adapter = (struct adapter *)arg1;
3979 	ifp = &adapter->arpcom.ac_if;
3980 
3981 	lwkt_serialize_enter(ifp->if_serializer);
3982 
3983 	if (result == 1)
3984 		em_print_debug_info(adapter);
3985 
3986 	/*
3987 	 * This value will cause a hex dump of the
3988 	 * first 32 16-bit words of the EEPROM to
3989 	 * the screen.
3990 	 */
3991 	if (result == 2)
3992 		em_print_nvm_info(adapter);
3993 
3994 	lwkt_serialize_exit(ifp->if_serializer);
3995 
3996 	return (error);
3997 }
3998 
3999 static int
4000 em_sysctl_stats(SYSCTL_HANDLER_ARGS)
4001 {
4002 	int error, result;
4003 
4004 	result = -1;
4005 	error = sysctl_handle_int(oidp, &result, 0, req);
4006 	if (error || !req->newptr)
4007 		return (error);
4008 
4009 	if (result == 1) {
4010 		struct adapter *adapter = (struct adapter *)arg1;
4011 		struct ifnet *ifp = &adapter->arpcom.ac_if;
4012 
4013 		lwkt_serialize_enter(ifp->if_serializer);
4014 		em_print_hw_stats(adapter);
4015 		lwkt_serialize_exit(ifp->if_serializer);
4016 	}
4017 	return (error);
4018 }
4019 
4020 static void
4021 em_add_sysctl(struct adapter *adapter)
4022 {
4023 	sysctl_ctx_init(&adapter->sysctl_ctx);
4024 	adapter->sysctl_tree = SYSCTL_ADD_NODE(&adapter->sysctl_ctx,
4025 					SYSCTL_STATIC_CHILDREN(_hw), OID_AUTO,
4026 					device_get_nameunit(adapter->dev),
4027 					CTLFLAG_RD, 0, "");
4028 	if (adapter->sysctl_tree == NULL) {
4029 		device_printf(adapter->dev, "can't add sysctl node\n");
4030 	} else {
4031 		SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
4032 		    SYSCTL_CHILDREN(adapter->sysctl_tree),
4033 		    OID_AUTO, "debug", CTLTYPE_INT|CTLFLAG_RW, adapter, 0,
4034 		    em_sysctl_debug_info, "I", "Debug Information");
4035 
4036 		SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
4037 		    SYSCTL_CHILDREN(adapter->sysctl_tree),
4038 		    OID_AUTO, "stats", CTLTYPE_INT|CTLFLAG_RW, adapter, 0,
4039 		    em_sysctl_stats, "I", "Statistics");
4040 
4041 		SYSCTL_ADD_INT(&adapter->sysctl_ctx,
4042 		    SYSCTL_CHILDREN(adapter->sysctl_tree),
4043 		    OID_AUTO, "rxd", CTLFLAG_RD,
4044 		    &adapter->num_rx_desc, 0, NULL);
4045 		SYSCTL_ADD_INT(&adapter->sysctl_ctx,
4046 		    SYSCTL_CHILDREN(adapter->sysctl_tree),
4047 		    OID_AUTO, "txd", CTLFLAG_RD,
4048 		    &adapter->num_tx_desc, 0, NULL);
4049 
4050 		if (adapter->hw.mac.type >= e1000_82540) {
4051 			SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
4052 			    SYSCTL_CHILDREN(adapter->sysctl_tree),
4053 			    OID_AUTO, "int_throttle_ceil",
4054 			    CTLTYPE_INT|CTLFLAG_RW, adapter, 0,
4055 			    em_sysctl_int_throttle, "I",
4056 			    "interrupt throttling rate");
4057 		}
4058 		SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
4059 		    SYSCTL_CHILDREN(adapter->sysctl_tree),
4060 		    OID_AUTO, "int_tx_nsegs",
4061 		    CTLTYPE_INT|CTLFLAG_RW, adapter, 0,
4062 		    em_sysctl_int_tx_nsegs, "I",
4063 		    "# segments per TX interrupt");
4064 		SYSCTL_ADD_INT(&adapter->sysctl_ctx,
4065 		    SYSCTL_CHILDREN(adapter->sysctl_tree),
4066 	            OID_AUTO, "wreg_tx_nsegs", CTLFLAG_RW,
4067 		    &adapter->tx_wreg_nsegs, 0,
4068 		    "# segments before write to hardware register");
4069 	}
4070 }
4071 
4072 static int
4073 em_sysctl_int_throttle(SYSCTL_HANDLER_ARGS)
4074 {
4075 	struct adapter *adapter = (void *)arg1;
4076 	struct ifnet *ifp = &adapter->arpcom.ac_if;
4077 	int error, throttle;
4078 
4079 	throttle = adapter->int_throttle_ceil;
4080 	error = sysctl_handle_int(oidp, &throttle, 0, req);
4081 	if (error || req->newptr == NULL)
4082 		return error;
4083 	if (throttle < 0 || throttle > 1000000000 / 256)
4084 		return EINVAL;
4085 
4086 	if (throttle) {
4087 		/*
4088 		 * Set the interrupt throttling rate in 256ns increments,
4089 		 * recalculate sysctl value assignment to get exact frequency.
4090 		 */
4091 		throttle = 1000000000 / 256 / throttle;
4092 
4093 		/* Upper 16bits of ITR is reserved and should be zero */
4094 		if (throttle & 0xffff0000)
4095 			return EINVAL;
4096 	}
4097 
4098 	lwkt_serialize_enter(ifp->if_serializer);
4099 
4100 	if (throttle)
4101 		adapter->int_throttle_ceil = 1000000000 / 256 / throttle;
4102 	else
4103 		adapter->int_throttle_ceil = 0;
4104 
4105 	if (ifp->if_flags & IFF_RUNNING)
4106 		em_set_itr(adapter, throttle);
4107 
4108 	lwkt_serialize_exit(ifp->if_serializer);
4109 
4110 	if (bootverbose) {
4111 		if_printf(ifp, "Interrupt moderation set to %d/sec\n",
4112 			  adapter->int_throttle_ceil);
4113 	}
4114 	return 0;
4115 }
4116 
4117 static int
4118 em_sysctl_int_tx_nsegs(SYSCTL_HANDLER_ARGS)
4119 {
4120 	struct adapter *adapter = (void *)arg1;
4121 	struct ifnet *ifp = &adapter->arpcom.ac_if;
4122 	int error, segs;
4123 
4124 	segs = adapter->tx_int_nsegs;
4125 	error = sysctl_handle_int(oidp, &segs, 0, req);
4126 	if (error || req->newptr == NULL)
4127 		return error;
4128 	if (segs <= 0)
4129 		return EINVAL;
4130 
4131 	lwkt_serialize_enter(ifp->if_serializer);
4132 
4133 	/*
4134 	 * Don't allow int_tx_nsegs to become:
4135 	 * o  Less the oact_tx_desc
4136 	 * o  Too large that no TX desc will cause TX interrupt to
4137 	 *    be generated (OACTIVE will never recover)
4138 	 * o  Too small that will cause tx_dd[] overflow
4139 	 */
4140 	if (segs < adapter->oact_tx_desc ||
4141 	    segs >= adapter->num_tx_desc - adapter->oact_tx_desc ||
4142 	    segs < adapter->num_tx_desc / EM_TXDD_SAFE) {
4143 		error = EINVAL;
4144 	} else {
4145 		error = 0;
4146 		adapter->tx_int_nsegs = segs;
4147 	}
4148 
4149 	lwkt_serialize_exit(ifp->if_serializer);
4150 
4151 	return error;
4152 }
4153 
4154 static void
4155 em_set_itr(struct adapter *adapter, uint32_t itr)
4156 {
4157 	E1000_WRITE_REG(&adapter->hw, E1000_ITR, itr);
4158 	if (adapter->hw.mac.type == e1000_82574) {
4159 		int i;
4160 
4161 		/*
4162 		 * When using MSIX interrupts we need to
4163 		 * throttle using the EITR register
4164 		 */
4165 		for (i = 0; i < 4; ++i) {
4166 			E1000_WRITE_REG(&adapter->hw,
4167 			    E1000_EITR_82574(i), itr);
4168 		}
4169 	}
4170 }
4171 
4172 static void
4173 em_disable_aspm(struct adapter *adapter)
4174 {
4175 	uint16_t link_cap, link_ctrl, disable;
4176 	uint8_t pcie_ptr, reg;
4177 	device_t dev = adapter->dev;
4178 
4179 	switch (adapter->hw.mac.type) {
4180 	case e1000_82571:
4181 	case e1000_82572:
4182 	case e1000_82573:
4183 		/*
4184 		 * 82573 specification update
4185 		 * errata #8 disable L0s
4186 		 * errata #41 disable L1
4187 		 *
4188 		 * 82571/82572 specification update
4189 		 # errata #13 disable L1
4190 		 * errata #68 disable L0s
4191 		 */
4192 		disable = PCIEM_LNKCTL_ASPM_L0S | PCIEM_LNKCTL_ASPM_L1;
4193 		break;
4194 
4195 	case e1000_82574:
4196 	case e1000_82583:
4197 		/*
4198 		 * 82574 specification update errata #20
4199 		 * 82583 specification update errata #9
4200 		 *
4201 		 * There is no need to disable L1
4202 		 */
4203 		disable = PCIEM_LNKCTL_ASPM_L0S;
4204 		break;
4205 
4206 	default:
4207 		return;
4208 	}
4209 
4210 	pcie_ptr = pci_get_pciecap_ptr(dev);
4211 	if (pcie_ptr == 0)
4212 		return;
4213 
4214 	link_cap = pci_read_config(dev, pcie_ptr + PCIER_LINKCAP, 2);
4215 	if ((link_cap & PCIEM_LNKCAP_ASPM_MASK) == 0)
4216 		return;
4217 
4218 	if (bootverbose) {
4219 		if_printf(&adapter->arpcom.ac_if,
4220 		    "disable ASPM %#02x\n", disable);
4221 	}
4222 
4223 	reg = pcie_ptr + PCIER_LINKCTRL;
4224 	link_ctrl = pci_read_config(dev, reg, 2);
4225 	link_ctrl &= ~disable;
4226 	pci_write_config(dev, reg, link_ctrl, 2);
4227 }
4228 
4229 static int
4230 em_tso_pullup(struct adapter *adapter, struct mbuf **mp)
4231 {
4232 	int iphlen, hoff, thoff, ex = 0;
4233 	struct mbuf *m;
4234 	struct ip *ip;
4235 
4236 	m = *mp;
4237 	KASSERT(M_WRITABLE(m), ("TSO mbuf not writable"));
4238 
4239 	iphlen = m->m_pkthdr.csum_iphlen;
4240 	thoff = m->m_pkthdr.csum_thlen;
4241 	hoff = m->m_pkthdr.csum_lhlen;
4242 
4243 	KASSERT(iphlen > 0, ("invalid ip hlen"));
4244 	KASSERT(thoff > 0, ("invalid tcp hlen"));
4245 	KASSERT(hoff > 0, ("invalid ether hlen"));
4246 
4247 	if (adapter->flags & EM_FLAG_TSO_PULLEX)
4248 		ex = 4;
4249 
4250 	if (m->m_len < hoff + iphlen + thoff + ex) {
4251 		m = m_pullup(m, hoff + iphlen + thoff + ex);
4252 		if (m == NULL) {
4253 			*mp = NULL;
4254 			return ENOBUFS;
4255 		}
4256 		*mp = m;
4257 	}
4258 	ip = mtodoff(m, struct ip *, hoff);
4259 	ip->ip_len = 0;
4260 
4261 	return 0;
4262 }
4263 
4264 static int
4265 em_tso_setup(struct adapter *adapter, struct mbuf *mp,
4266     uint32_t *txd_upper, uint32_t *txd_lower)
4267 {
4268 	struct e1000_context_desc *TXD;
4269 	int hoff, iphlen, thoff, hlen;
4270 	int mss, pktlen, curr_txd;
4271 
4272 	iphlen = mp->m_pkthdr.csum_iphlen;
4273 	thoff = mp->m_pkthdr.csum_thlen;
4274 	hoff = mp->m_pkthdr.csum_lhlen;
4275 	mss = mp->m_pkthdr.tso_segsz;
4276 	pktlen = mp->m_pkthdr.len;
4277 
4278 	if (adapter->csum_flags == CSUM_TSO &&
4279 	    adapter->csum_iphlen == iphlen &&
4280 	    adapter->csum_lhlen == hoff &&
4281 	    adapter->csum_thlen == thoff &&
4282 	    adapter->csum_mss == mss &&
4283 	    adapter->csum_pktlen == pktlen) {
4284 		*txd_upper = adapter->csum_txd_upper;
4285 		*txd_lower = adapter->csum_txd_lower;
4286 		return 0;
4287 	}
4288 	hlen = hoff + iphlen + thoff;
4289 
4290 	/*
4291 	 * Setup a new TSO context.
4292 	 */
4293 
4294 	curr_txd = adapter->next_avail_tx_desc;
4295 	TXD = (struct e1000_context_desc *)&adapter->tx_desc_base[curr_txd];
4296 
4297 	*txd_lower = E1000_TXD_CMD_DEXT |	/* Extended descr type */
4298 		     E1000_TXD_DTYP_D |		/* Data descr type */
4299 		     E1000_TXD_CMD_TSE;		/* Do TSE on this packet */
4300 
4301 	/* IP and/or TCP header checksum calculation and insertion. */
4302 	*txd_upper = (E1000_TXD_POPTS_IXSM | E1000_TXD_POPTS_TXSM) << 8;
4303 
4304 	/*
4305 	 * Start offset for header checksum calculation.
4306 	 * End offset for header checksum calculation.
4307 	 * Offset of place put the checksum.
4308 	 */
4309 	TXD->lower_setup.ip_fields.ipcss = hoff;
4310 	TXD->lower_setup.ip_fields.ipcse = htole16(hoff + iphlen - 1);
4311 	TXD->lower_setup.ip_fields.ipcso = hoff + offsetof(struct ip, ip_sum);
4312 
4313 	/*
4314 	 * Start offset for payload checksum calculation.
4315 	 * End offset for payload checksum calculation.
4316 	 * Offset of place to put the checksum.
4317 	 */
4318 	TXD->upper_setup.tcp_fields.tucss = hoff + iphlen;
4319 	TXD->upper_setup.tcp_fields.tucse = 0;
4320 	TXD->upper_setup.tcp_fields.tucso =
4321 	    hoff + iphlen + offsetof(struct tcphdr, th_sum);
4322 
4323 	/*
4324 	 * Payload size per packet w/o any headers.
4325 	 * Length of all headers up to payload.
4326 	 */
4327 	TXD->tcp_seg_setup.fields.mss = htole16(mss);
4328 	TXD->tcp_seg_setup.fields.hdr_len = hlen;
4329 	TXD->cmd_and_length = htole32(E1000_TXD_CMD_IFCS |
4330 				E1000_TXD_CMD_DEXT |	/* Extended descr */
4331 				E1000_TXD_CMD_TSE |	/* TSE context */
4332 				E1000_TXD_CMD_IP |	/* Do IP csum */
4333 				E1000_TXD_CMD_TCP |	/* Do TCP checksum */
4334 				(pktlen - hlen));	/* Total len */
4335 
4336 	/* Save the information for this TSO context */
4337 	adapter->csum_flags = CSUM_TSO;
4338 	adapter->csum_lhlen = hoff;
4339 	adapter->csum_iphlen = iphlen;
4340 	adapter->csum_thlen = thoff;
4341 	adapter->csum_mss = mss;
4342 	adapter->csum_pktlen = pktlen;
4343 	adapter->csum_txd_upper = *txd_upper;
4344 	adapter->csum_txd_lower = *txd_lower;
4345 
4346 	if (++curr_txd == adapter->num_tx_desc)
4347 		curr_txd = 0;
4348 
4349 	KKASSERT(adapter->num_tx_desc_avail > 0);
4350 	adapter->num_tx_desc_avail--;
4351 
4352 	adapter->next_avail_tx_desc = curr_txd;
4353 	return 1;
4354 }
4355