xref: /dflybsd-src/sys/dev/netif/em/if_em.c (revision be7fdc210cff5bb7cb8b29f8f573b8bf445934f1)
1 /*
2  *
3  * Copyright (c) 2004 Joerg Sonnenberger <joerg@bec.de>.  All rights reserved.
4  *
5  * Copyright (c) 2001-2005, Intel Corporation
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions are met:
10  *
11  *  1. Redistributions of source code must retain the above copyright notice,
12  *     this list of conditions and the following disclaimer.
13  *
14  *  2. Redistributions in binary form must reproduce the above copyright
15  *     notice, this list of conditions and the following disclaimer in the
16  *     documentation and/or other materials provided with the distribution.
17  *
18  *  3. Neither the name of the Intel Corporation nor the names of its
19  *     contributors may be used to endorse or promote products derived from
20  *     this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
23  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
26  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32  * POSSIBILITY OF SUCH DAMAGE.
33  *
34  *
35  * Copyright (c) 2005 The DragonFly Project.  All rights reserved.
36  *
37  * This code is derived from software contributed to The DragonFly Project
38  * by Matthew Dillon <dillon@backplane.com>
39  *
40  * Redistribution and use in source and binary forms, with or without
41  * modification, are permitted provided that the following conditions
42  * are met:
43  *
44  * 1. Redistributions of source code must retain the above copyright
45  *    notice, this list of conditions and the following disclaimer.
46  * 2. Redistributions in binary form must reproduce the above copyright
47  *    notice, this list of conditions and the following disclaimer in
48  *    the documentation and/or other materials provided with the
49  *    distribution.
50  * 3. Neither the name of The DragonFly Project nor the names of its
51  *    contributors may be used to endorse or promote products derived
52  *    from this software without specific, prior written permission.
53  *
54  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
55  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
56  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
57  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
58  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
59  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
60  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
61  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
62  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
63  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
64  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
65  * SUCH DAMAGE.
66  *
67  * $DragonFly: src/sys/dev/netif/em/if_em.c,v 1.46 2005/12/31 14:07:59 sephe Exp $
68  * $FreeBSD$
69  */
70 /*
71  * SERIALIZATION API RULES:
72  *
73  * - If the driver uses the same serializer for the interrupt as for the
74  *   ifnet, most of the serialization will be done automatically for the
75  *   driver.
76  *
77  * - ifmedia entry points will be serialized by the ifmedia code using the
78  *   ifnet serializer.
79  *
80  * - if_* entry points except for if_input will be serialized by the IF
81  *   and protocol layers.
82  *
83  * - The device driver must be sure to serialize access from timeout code
84  *   installed by the device driver.
85  *
86  * - The device driver typically holds the serializer at the time it wishes
87  *   to call if_input.  If so, it should pass the serializer to if_input and
88  *   note that the serializer might be dropped temporarily by if_input
89  *   (e.g. in case it has to bridge the packet to another interface).
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_polling.h"
97 
98 #include <dev/netif/em/if_em.h>
99 #include <net/ifq_var.h>
100 
101 /*********************************************************************
102  *  Set this to one to display debug statistics
103  *********************************************************************/
104 int             em_display_debug_stats = 0;
105 
106 /*********************************************************************
107  *  Driver version
108  *********************************************************************/
109 
110 char em_driver_version[] = "3.2.15";
111 
112 
113 /*********************************************************************
114  *  PCI Device ID Table
115  *
116  *  Used by probe to select devices to load on
117  *  Last field stores an index into em_strings
118  *  Last entry must be all 0s
119  *
120  *  { Vendor ID, Device ID, SubVendor ID, SubDevice ID, String Index }
121  *********************************************************************/
122 
123 static em_vendor_info_t em_vendor_info_array[] =
124 {
125 	/* Intel(R) PRO/1000 Network Connection */
126 	{ 0x8086, E1000_DEV_ID_82540EM,		PCI_ANY_ID, PCI_ANY_ID, 0},
127 	{ 0x8086, E1000_DEV_ID_82540EM_LOM,	PCI_ANY_ID, PCI_ANY_ID, 0},
128 	{ 0x8086, E1000_DEV_ID_82540EP,		PCI_ANY_ID, PCI_ANY_ID, 0},
129 	{ 0x8086, E1000_DEV_ID_82540EP_LOM,	PCI_ANY_ID, PCI_ANY_ID, 0},
130 	{ 0x8086, E1000_DEV_ID_82540EP_LP,	PCI_ANY_ID, PCI_ANY_ID, 0},
131 
132 	{ 0x8086, E1000_DEV_ID_82541EI,		PCI_ANY_ID, PCI_ANY_ID, 0},
133 	{ 0x8086, E1000_DEV_ID_82541ER,		PCI_ANY_ID, PCI_ANY_ID, 0},
134 	{ 0x8086, E1000_DEV_ID_82541EI_MOBILE,	PCI_ANY_ID, PCI_ANY_ID, 0},
135 	{ 0x8086, E1000_DEV_ID_82541GI,		PCI_ANY_ID, PCI_ANY_ID, 0},
136 	{ 0x8086, E1000_DEV_ID_82541GI_LF,	PCI_ANY_ID, PCI_ANY_ID, 0},
137 	{ 0x8086, E1000_DEV_ID_82541GI_MOBILE,	PCI_ANY_ID, PCI_ANY_ID, 0},
138 
139 	{ 0x8086, E1000_DEV_ID_82542,		PCI_ANY_ID, PCI_ANY_ID, 0},
140 
141 	{ 0x8086, E1000_DEV_ID_82543GC_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
142 	{ 0x8086, E1000_DEV_ID_82543GC_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
143 
144 	{ 0x8086, E1000_DEV_ID_82544EI_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
145 	{ 0x8086, E1000_DEV_ID_82544EI_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
146 	{ 0x8086, E1000_DEV_ID_82544GC_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
147 	{ 0x8086, E1000_DEV_ID_82544GC_LOM,	PCI_ANY_ID, PCI_ANY_ID, 0},
148 
149 	{ 0x8086, E1000_DEV_ID_82545EM_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
150 	{ 0x8086, E1000_DEV_ID_82545EM_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
151 	{ 0x8086, E1000_DEV_ID_82545GM_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
152 	{ 0x8086, E1000_DEV_ID_82545GM_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
153 	{ 0x8086, E1000_DEV_ID_82545GM_SERDES,	PCI_ANY_ID, PCI_ANY_ID, 0},
154 
155 	{ 0x8086, E1000_DEV_ID_82546EB_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
156 	{ 0x8086, E1000_DEV_ID_82546EB_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
157 	{ 0x8086, E1000_DEV_ID_82546EB_QUAD_COPPER, PCI_ANY_ID, PCI_ANY_ID, 0},
158 	{ 0x8086, E1000_DEV_ID_82546GB_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
159 	{ 0x8086, E1000_DEV_ID_82546GB_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
160 	{ 0x8086, E1000_DEV_ID_82546GB_SERDES,	PCI_ANY_ID, PCI_ANY_ID, 0},
161 	{ 0x8086, E1000_DEV_ID_82546GB_PCIE,	PCI_ANY_ID, PCI_ANY_ID, 0},
162 #ifdef KINGSPORT_PROJECT
163 	{ 0x8086, E1000_DEV_ID_82546GB_QUAD_COPPER, PCI_ANY_ID, PCI_ANY_ID, 0},
164 #endif	/* KINGSPORT_PROJECT */
165 
166 	{ 0x8086, E1000_DEV_ID_82547EI,		PCI_ANY_ID, PCI_ANY_ID, 0},
167 	{ 0x8086, E1000_DEV_ID_82547GI,		PCI_ANY_ID, PCI_ANY_ID, 0},
168 
169 	{ 0x8086, E1000_DEV_ID_82571EB_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
170 	{ 0x8086, E1000_DEV_ID_82571EB_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
171 	{ 0x8086, E1000_DEV_ID_82571EB_SERDES,	PCI_ANY_ID, PCI_ANY_ID, 0},
172 
173 	{ 0x8086, E1000_DEV_ID_82572EI_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
174 	{ 0x8086, E1000_DEV_ID_82572EI_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
175 	{ 0x8086, E1000_DEV_ID_82572EI_SERDES,	PCI_ANY_ID, PCI_ANY_ID, 0},
176 
177 	{ 0x8086, E1000_DEV_ID_82573E,		PCI_ANY_ID, PCI_ANY_ID, 0},
178 	{ 0x8086, E1000_DEV_ID_82573E_IAMT,	PCI_ANY_ID, PCI_ANY_ID, 0},
179 	{ 0x8086, E1000_DEV_ID_82573L,		PCI_ANY_ID, PCI_ANY_ID, 0},
180 
181 	{ 0x8086, 0x101A, PCI_ANY_ID, PCI_ANY_ID, 0},
182 	{ 0x8086, 0x1014, PCI_ANY_ID, PCI_ANY_ID, 0},
183 	/* required last entry */
184 	{ 0, 0, 0, 0, 0}
185 };
186 
187 /*********************************************************************
188  *  Table of branding strings for all supported NICs.
189  *********************************************************************/
190 
191 static const char *em_strings[] = {
192 	"Intel(R) PRO/1000 Network Connection"
193 };
194 
195 /*********************************************************************
196  *  Function prototypes
197  *********************************************************************/
198 static int	em_probe(device_t);
199 static int	em_attach(device_t);
200 static int	em_detach(device_t);
201 static int	em_shutdown(device_t);
202 static void	em_intr(void *);
203 static void	em_start(struct ifnet *);
204 static int	em_ioctl(struct ifnet *, u_long, caddr_t, struct ucred *);
205 static void	em_watchdog(struct ifnet *);
206 static void	em_init(void *);
207 static void	em_stop(void *);
208 static void	em_media_status(struct ifnet *, struct ifmediareq *);
209 static int	em_media_change(struct ifnet *);
210 static void	em_identify_hardware(struct adapter *);
211 static void	em_local_timer(void *);
212 static int	em_hardware_init(struct adapter *);
213 static void	em_setup_interface(device_t, struct adapter *);
214 static int	em_setup_transmit_structures(struct adapter *);
215 static void	em_initialize_transmit_unit(struct adapter *);
216 static int	em_setup_receive_structures(struct adapter *);
217 static void	em_initialize_receive_unit(struct adapter *);
218 static void	em_enable_intr(struct adapter *);
219 static void	em_disable_intr(struct adapter *);
220 static void	em_free_transmit_structures(struct adapter *);
221 static void	em_free_receive_structures(struct adapter *);
222 static void	em_update_stats_counters(struct adapter *);
223 static void	em_clean_transmit_interrupts(struct adapter *);
224 static int	em_allocate_receive_structures(struct adapter *);
225 static int	em_allocate_transmit_structures(struct adapter *);
226 static void	em_process_receive_interrupts(struct adapter *, int);
227 static void	em_receive_checksum(struct adapter *, struct em_rx_desc *,
228 				    struct mbuf *);
229 static void	em_transmit_checksum_setup(struct adapter *, struct mbuf *,
230 					   uint32_t *, uint32_t *);
231 static void	em_set_promisc(struct adapter *);
232 static void	em_disable_promisc(struct adapter *);
233 static void	em_set_multi(struct adapter *);
234 static void	em_print_hw_stats(struct adapter *);
235 static void	em_print_link_status(struct adapter *);
236 static int	em_get_buf(int i, struct adapter *, struct mbuf *, int how);
237 static void	em_enable_vlans(struct adapter *);
238 static int	em_encap(struct adapter *, struct mbuf *);
239 static void	em_smartspeed(struct adapter *);
240 static int	em_82547_fifo_workaround(struct adapter *, int);
241 static void	em_82547_update_fifo_head(struct adapter *, int);
242 static int	em_82547_tx_fifo_reset(struct adapter *);
243 static void	em_82547_move_tail(void *arg);
244 static void	em_82547_move_tail_serialized(void *arg);
245 static int	em_dma_malloc(struct adapter *, bus_size_t,
246 			      struct em_dma_alloc *, int);
247 static void	em_dma_free(struct adapter *, struct em_dma_alloc *);
248 static void	em_print_debug_info(struct adapter *);
249 static int	em_is_valid_ether_addr(uint8_t *);
250 static int	em_sysctl_stats(SYSCTL_HANDLER_ARGS);
251 static int	em_sysctl_debug_info(SYSCTL_HANDLER_ARGS);
252 static uint32_t	em_fill_descriptors(uint64_t address, uint32_t length,
253 				   PDESC_ARRAY desc_array);
254 static int	em_sysctl_int_delay(SYSCTL_HANDLER_ARGS);
255 static int	em_sysctl_int_throttle(SYSCTL_HANDLER_ARGS);
256 static void	em_add_int_delay_sysctl(struct adapter *, const char *,
257 					const char *,
258 					struct em_int_delay_info *, int, int);
259 
260 /*********************************************************************
261  *  FreeBSD Device Interface Entry Points
262  *********************************************************************/
263 
264 static device_method_t em_methods[] = {
265 	/* Device interface */
266 	DEVMETHOD(device_probe, em_probe),
267 	DEVMETHOD(device_attach, em_attach),
268 	DEVMETHOD(device_detach, em_detach),
269 	DEVMETHOD(device_shutdown, em_shutdown),
270 	{0, 0}
271 };
272 
273 static driver_t em_driver = {
274 	"em", em_methods, sizeof(struct adapter),
275 };
276 
277 static devclass_t em_devclass;
278 
279 DECLARE_DUMMY_MODULE(if_em);
280 DRIVER_MODULE(if_em, pci, em_driver, em_devclass, 0, 0);
281 
282 /*********************************************************************
283  *  Tunable default values.
284  *********************************************************************/
285 
286 #define E1000_TICKS_TO_USECS(ticks)	((1024 * (ticks) + 500) / 1000)
287 #define E1000_USECS_TO_TICKS(usecs)	((1000 * (usecs) + 512) / 1024)
288 
289 static int em_tx_int_delay_dflt = E1000_TICKS_TO_USECS(EM_TIDV);
290 static int em_rx_int_delay_dflt = E1000_TICKS_TO_USECS(EM_RDTR);
291 static int em_tx_abs_int_delay_dflt = E1000_TICKS_TO_USECS(EM_TADV);
292 static int em_rx_abs_int_delay_dflt = E1000_TICKS_TO_USECS(EM_RADV);
293 static int em_int_throttle_ceil = 10000;
294 
295 TUNABLE_INT("hw.em.tx_int_delay", &em_tx_int_delay_dflt);
296 TUNABLE_INT("hw.em.rx_int_delay", &em_rx_int_delay_dflt);
297 TUNABLE_INT("hw.em.tx_abs_int_delay", &em_tx_abs_int_delay_dflt);
298 TUNABLE_INT("hw.em.rx_abs_int_delay", &em_rx_abs_int_delay_dflt);
299 TUNABLE_INT("hw.em.int_throttle_ceil", &em_int_throttle_ceil);
300 
301 /*
302  * Kernel trace for characterization of operations
303  */
304 #if !defined(KTR_IF_EM)
305 #define KTR_IF_EM	KTR_ALL
306 #endif
307 KTR_INFO_MASTER(if_em);
308 KTR_INFO(KTR_IF_EM, if_em, intr_beg, 0, "intr begin", 0);
309 KTR_INFO(KTR_IF_EM, if_em, intr_end, 1, "intr end", 0);
310 KTR_INFO(KTR_IF_EM, if_em, poll_beg, 2, "poll begin", 0);
311 KTR_INFO(KTR_IF_EM, if_em, poll_end, 3, "poll end", 0);
312 KTR_INFO(KTR_IF_EM, if_em, pkt_receive, 4, "rx packet", 0);
313 KTR_INFO(KTR_IF_EM, if_em, pkt_txqueue, 5, "tx packet", 0);
314 KTR_INFO(KTR_IF_EM, if_em, pkt_txclean, 6, "tx clean", 0);
315 #define logif(name)	KTR_LOG(if_em_ ## name)
316 
317 /*********************************************************************
318  *  Device identification routine
319  *
320  *  em_probe determines if the driver should be loaded on
321  *  adapter based on PCI vendor/device id of the adapter.
322  *
323  *  return 0 on success, positive on failure
324  *********************************************************************/
325 
326 static int
327 em_probe(device_t dev)
328 {
329 	em_vendor_info_t *ent;
330 
331 	uint16_t pci_vendor_id = 0;
332 	uint16_t pci_device_id = 0;
333 	uint16_t pci_subvendor_id = 0;
334 	uint16_t pci_subdevice_id = 0;
335 	char adapter_name[60];
336 
337 	INIT_DEBUGOUT("em_probe: begin");
338 
339 	pci_vendor_id = pci_get_vendor(dev);
340 	if (pci_vendor_id != EM_VENDOR_ID)
341 		return(ENXIO);
342 
343 	pci_device_id = pci_get_device(dev);
344 	pci_subvendor_id = pci_get_subvendor(dev);
345 	pci_subdevice_id = pci_get_subdevice(dev);
346 
347 	ent = em_vendor_info_array;
348 	while (ent->vendor_id != 0) {
349 		if ((pci_vendor_id == ent->vendor_id) &&
350 		    (pci_device_id == ent->device_id) &&
351 
352 		    ((pci_subvendor_id == ent->subvendor_id) ||
353 		     (ent->subvendor_id == PCI_ANY_ID)) &&
354 
355 		    ((pci_subdevice_id == ent->subdevice_id) ||
356 		     (ent->subdevice_id == PCI_ANY_ID))) {
357 			snprintf(adapter_name, sizeof(adapter_name),
358 				 "%s, Version - %s",  em_strings[ent->index],
359 				 em_driver_version);
360 			device_set_desc_copy(dev, adapter_name);
361 			return(0);
362 		}
363 		ent++;
364 	}
365 
366 	return(ENXIO);
367 }
368 
369 /*********************************************************************
370  *  Device initialization routine
371  *
372  *  The attach entry point is called when the driver is being loaded.
373  *  This routine identifies the type of hardware, allocates all resources
374  *  and initializes the hardware.
375  *
376  *  return 0 on success, positive on failure
377  *********************************************************************/
378 
379 static int
380 em_attach(device_t dev)
381 {
382 	struct adapter *adapter;
383 	int tsize, rsize;
384 	int i, val, rid;
385 	int error = 0;
386 
387 	INIT_DEBUGOUT("em_attach: begin");
388 
389 	adapter = device_get_softc(dev);
390 
391 	callout_init(&adapter->timer);
392 	callout_init(&adapter->tx_fifo_timer);
393 
394 	adapter->dev = dev;
395 	adapter->osdep.dev = dev;
396 
397 	/* SYSCTL stuff */
398 	sysctl_ctx_init(&adapter->sysctl_ctx);
399 	adapter->sysctl_tree = SYSCTL_ADD_NODE(&adapter->sysctl_ctx,
400 					       SYSCTL_STATIC_CHILDREN(_hw),
401 					       OID_AUTO,
402 					       device_get_nameunit(dev),
403 					       CTLFLAG_RD,
404 					       0, "");
405 
406 	if (adapter->sysctl_tree == NULL) {
407 		error = EIO;
408 		goto fail;
409 	}
410 
411 	SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
412 			SYSCTL_CHILDREN(adapter->sysctl_tree),
413 			OID_AUTO, "debug_info", CTLTYPE_INT|CTLFLAG_RW,
414 			(void *)adapter, 0,
415 			em_sysctl_debug_info, "I", "Debug Information");
416 
417 	SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
418 			SYSCTL_CHILDREN(adapter->sysctl_tree),
419 			OID_AUTO, "stats", CTLTYPE_INT|CTLFLAG_RW,
420 			(void *)adapter, 0,
421 			em_sysctl_stats, "I", "Statistics");
422 
423 	/* Determine hardware revision */
424 	em_identify_hardware(adapter);
425 
426 	/* Set up some sysctls for the tunable interrupt delays */
427 	em_add_int_delay_sysctl(adapter, "rx_int_delay",
428 				"receive interrupt delay in usecs",
429 				&adapter->rx_int_delay,
430 				E1000_REG_OFFSET(&adapter->hw, RDTR),
431 				em_rx_int_delay_dflt);
432         em_add_int_delay_sysctl(adapter, "tx_int_delay",
433 				"transmit interrupt delay in usecs",
434 				&adapter->tx_int_delay,
435 				E1000_REG_OFFSET(&adapter->hw, TIDV),
436 				em_tx_int_delay_dflt);
437 	if (adapter->hw.mac_type >= em_82540) {
438 		em_add_int_delay_sysctl(adapter, "rx_abs_int_delay",
439 					"receive interrupt delay limit in usecs",
440 					&adapter->rx_abs_int_delay,
441 					E1000_REG_OFFSET(&adapter->hw, RADV),
442 					em_rx_abs_int_delay_dflt);
443 		em_add_int_delay_sysctl(adapter, "tx_abs_int_delay",
444 					"transmit interrupt delay limit in usecs",
445 					&adapter->tx_abs_int_delay,
446 					E1000_REG_OFFSET(&adapter->hw, TADV),
447 					em_tx_abs_int_delay_dflt);
448 		SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
449 			SYSCTL_CHILDREN(adapter->sysctl_tree),
450 			OID_AUTO, "int_throttle_ceil", CTLTYPE_INT|CTLFLAG_RW,
451 			adapter, 0, em_sysctl_int_throttle, "I", NULL);
452 	}
453 
454 	/* Parameters (to be read from user) */
455 	adapter->num_tx_desc = EM_MAX_TXD;
456 	adapter->num_rx_desc = EM_MAX_RXD;
457 	adapter->hw.autoneg = DO_AUTO_NEG;
458 	adapter->hw.wait_autoneg_complete = WAIT_FOR_AUTO_NEG_DEFAULT;
459 	adapter->hw.autoneg_advertised = AUTONEG_ADV_DEFAULT;
460 	adapter->hw.tbi_compatibility_en = TRUE;
461 	adapter->rx_buffer_len = EM_RXBUFFER_2048;
462 
463 	adapter->hw.phy_init_script = 1;
464 	adapter->hw.phy_reset_disable = FALSE;
465 
466 #ifndef EM_MASTER_SLAVE
467 	adapter->hw.master_slave = em_ms_hw_default;
468 #else
469 	adapter->hw.master_slave = EM_MASTER_SLAVE;
470 #endif
471 
472 	/*
473 	 * Set the max frame size assuming standard ethernet
474 	 * sized frames
475 	 */
476 	adapter->hw.max_frame_size = ETHERMTU + ETHER_HDR_LEN + ETHER_CRC_LEN;
477 
478 	adapter->hw.min_frame_size =
479 	    MINIMUM_ETHERNET_PACKET_SIZE + ETHER_CRC_LEN;
480 
481 	/*
482 	 * This controls when hardware reports transmit completion
483 	 * status.
484 	 */
485 	adapter->hw.report_tx_early = 1;
486 
487 	rid = EM_MMBA;
488 	adapter->res_memory = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
489 						     &rid, RF_ACTIVE);
490 	if (!(adapter->res_memory)) {
491 		device_printf(dev, "Unable to allocate bus resource: memory\n");
492 		error = ENXIO;
493 		goto fail;
494 	}
495 	adapter->osdep.mem_bus_space_tag =
496 	    rman_get_bustag(adapter->res_memory);
497 	adapter->osdep.mem_bus_space_handle =
498 	    rman_get_bushandle(adapter->res_memory);
499 	adapter->hw.hw_addr = (uint8_t *)&adapter->osdep.mem_bus_space_handle;
500 
501 	if (adapter->hw.mac_type > em_82543) {
502 		/* Figure our where our IO BAR is ? */
503 		rid = EM_MMBA;
504 		for (i = 0; i < 5; i++) {
505 			val = pci_read_config(dev, rid, 4);
506 			if (val & 0x00000001) {
507 				adapter->io_rid = rid;
508 				break;
509 			}
510 			rid += 4;
511 		}
512 
513 		adapter->res_ioport = bus_alloc_resource_any(dev,
514 		    SYS_RES_IOPORT, &adapter->io_rid, RF_ACTIVE);
515 		if (!(adapter->res_ioport)) {
516 			device_printf(dev, "Unable to allocate bus resource: ioport\n");
517 			error = ENXIO;
518 			goto fail;
519 		}
520 
521 		adapter->hw.reg_io_tag = rman_get_bustag(adapter->res_ioport);
522 		adapter->hw.reg_io_handle = rman_get_bushandle(adapter->res_ioport);
523 	}
524 
525 	rid = 0x0;
526 	adapter->res_interrupt = bus_alloc_resource_any(dev, SYS_RES_IRQ,
527 	    &rid, RF_SHAREABLE | RF_ACTIVE);
528 	if (!(adapter->res_interrupt)) {
529 		device_printf(dev, "Unable to allocate bus resource: interrupt\n");
530 		error = ENXIO;
531 		goto fail;
532 	}
533 
534 	adapter->hw.back = &adapter->osdep;
535 
536 	em_init_eeprom_params(&adapter->hw);
537 
538 	tsize = EM_ROUNDUP(adapter->num_tx_desc *
539 			   sizeof(struct em_tx_desc), 4096);
540 
541 	/* Allocate Transmit Descriptor ring */
542 	if (em_dma_malloc(adapter, tsize, &adapter->txdma, BUS_DMA_WAITOK)) {
543 		device_printf(dev, "Unable to allocate TxDescriptor memory\n");
544 		error = ENOMEM;
545 		goto fail;
546 	}
547 	adapter->tx_desc_base = (struct em_tx_desc *) adapter->txdma.dma_vaddr;
548 
549 	rsize = EM_ROUNDUP(adapter->num_rx_desc *
550 			   sizeof(struct em_rx_desc), 4096);
551 
552 	/* Allocate Receive Descriptor ring */
553 	if (em_dma_malloc(adapter, rsize, &adapter->rxdma, BUS_DMA_WAITOK)) {
554 		device_printf(dev, "Unable to allocate rx_desc memory\n");
555 		error = ENOMEM;
556 		goto fail;
557 	}
558 	adapter->rx_desc_base = (struct em_rx_desc *) adapter->rxdma.dma_vaddr;
559 
560 	/* Initialize the hardware */
561 	if (em_hardware_init(adapter)) {
562 		device_printf(dev, "Unable to initialize the hardware\n");
563 		error = EIO;
564 		goto fail;
565 	}
566 
567 	/* Copy the permanent MAC address out of the EEPROM */
568 	if (em_read_mac_addr(&adapter->hw) < 0) {
569 		device_printf(dev, "EEPROM read error while reading mac address\n");
570 		error = EIO;
571 		goto fail;
572 	}
573 
574 	if (!em_is_valid_ether_addr(adapter->hw.mac_addr)) {
575 		device_printf(dev, "Invalid mac address\n");
576 		error = EIO;
577 		goto fail;
578 	}
579 
580 	/* Setup OS specific network interface */
581 	em_setup_interface(dev, adapter);
582 
583 	/* Initialize statistics */
584 	em_clear_hw_cntrs(&adapter->hw);
585 	em_update_stats_counters(adapter);
586 	adapter->hw.get_link_status = 1;
587 	em_check_for_link(&adapter->hw);
588 
589 	/* Print the link status */
590 	if (adapter->link_active == 1) {
591 		em_get_speed_and_duplex(&adapter->hw, &adapter->link_speed,
592 					&adapter->link_duplex);
593 		device_printf(dev, "Speed: %d Mbps, Duplex: %s\n",
594 		    adapter->link_speed,
595 		    adapter->link_duplex == FULL_DUPLEX ? "Full" : "Half");
596 	} else
597 		device_printf(dev, "Speed: N/A, Duplex:N/A\n");
598 
599 	/* Identify 82544 on PCIX */
600 	em_get_bus_info(&adapter->hw);
601 	if (adapter->hw.bus_type == em_bus_type_pcix &&
602 	    adapter->hw.mac_type == em_82544)
603 		adapter->pcix_82544 = TRUE;
604         else
605 		adapter->pcix_82544 = FALSE;
606 
607 	error = bus_setup_intr(dev, adapter->res_interrupt, INTR_NETSAFE,
608 			   (void (*)(void *)) em_intr, adapter,
609 			   &adapter->int_handler_tag,
610 			   adapter->interface_data.ac_if.if_serializer);
611 	if (error) {
612 		device_printf(dev, "Error registering interrupt handler!\n");
613 		ether_ifdetach(&adapter->interface_data.ac_if);
614 		goto fail;
615 	}
616 
617 	INIT_DEBUGOUT("em_attach: end");
618 	return(0);
619 
620 fail:
621 	em_detach(dev);
622 	return(error);
623 }
624 
625 /*********************************************************************
626  *  Device removal routine
627  *
628  *  The detach entry point is called when the driver is being removed.
629  *  This routine stops the adapter and deallocates all the resources
630  *  that were allocated for driver operation.
631  *
632  *  return 0 on success, positive on failure
633  *********************************************************************/
634 
635 static int
636 em_detach(device_t dev)
637 {
638 	struct adapter *adapter = device_get_softc(dev);
639 
640 	INIT_DEBUGOUT("em_detach: begin");
641 
642 	if (device_is_attached(dev)) {
643 		struct ifnet *ifp = &adapter->interface_data.ac_if;
644 
645 		lwkt_serialize_enter(ifp->if_serializer);
646 		adapter->in_detach = 1;
647 		em_stop(adapter);
648 		em_phy_hw_reset(&adapter->hw);
649 		bus_teardown_intr(dev, adapter->res_interrupt,
650 				  adapter->int_handler_tag);
651 		lwkt_serialize_exit(ifp->if_serializer);
652 
653 		ether_ifdetach(ifp);
654 	}
655 	bus_generic_detach(dev);
656 
657 	if (adapter->res_interrupt != NULL) {
658 		bus_release_resource(dev, SYS_RES_IRQ, 0,
659 				     adapter->res_interrupt);
660 	}
661 	if (adapter->res_memory != NULL) {
662 		bus_release_resource(dev, SYS_RES_MEMORY, EM_MMBA,
663 				     adapter->res_memory);
664 	}
665 
666 	if (adapter->res_ioport != NULL) {
667 		bus_release_resource(dev, SYS_RES_IOPORT, adapter->io_rid,
668 				     adapter->res_ioport);
669 	}
670 
671 	/* Free Transmit Descriptor ring */
672 	if (adapter->tx_desc_base != NULL) {
673 		em_dma_free(adapter, &adapter->txdma);
674 		adapter->tx_desc_base = NULL;
675 	}
676 
677 	/* Free Receive Descriptor ring */
678 	if (adapter->rx_desc_base != NULL) {
679 		em_dma_free(adapter, &adapter->rxdma);
680 		adapter->rx_desc_base = NULL;
681 	}
682 
683 	adapter->sysctl_tree = NULL;
684 	sysctl_ctx_free(&adapter->sysctl_ctx);
685 
686 	return(0);
687 }
688 
689 /*********************************************************************
690  *
691  *  Shutdown entry point
692  *
693  **********************************************************************/
694 
695 static int
696 em_shutdown(device_t dev)
697 {
698 	struct adapter *adapter = device_get_softc(dev);
699 	em_stop(adapter);
700 	return(0);
701 }
702 
703 /*********************************************************************
704  *  Transmit entry point
705  *
706  *  em_start is called by the stack to initiate a transmit.
707  *  The driver will remain in this routine as long as there are
708  *  packets to transmit and transmit resources are available.
709  *  In case resources are not available stack is notified and
710  *  the packet is requeued.
711  **********************************************************************/
712 
713 static void
714 em_start(struct ifnet *ifp)
715 {
716 	struct mbuf *m_head;
717 	struct adapter *adapter = ifp->if_softc;
718 
719 	ASSERT_SERIALIZED(adapter->interface_data.ac_if.if_serializer);
720 
721 	if (!adapter->link_active)
722 		return;
723 	while (!ifq_is_empty(&ifp->if_snd)) {
724 		m_head = ifq_poll(&ifp->if_snd);
725 
726 		if (m_head == NULL)
727 			break;
728 
729 		logif(pkt_txqueue);
730 		if (em_encap(adapter, m_head)) {
731 			ifp->if_flags |= IFF_OACTIVE;
732 			break;
733 		}
734 		ifq_dequeue(&ifp->if_snd, m_head);
735 
736 		/* Send a copy of the frame to the BPF listener */
737 		BPF_MTAP(ifp, m_head);
738 
739 		/* Set timeout in case hardware has problems transmitting */
740 		ifp->if_timer = EM_TX_TIMEOUT;
741 	}
742 }
743 
744 /*********************************************************************
745  *  Ioctl entry point
746  *
747  *  em_ioctl is called when the user wants to configure the
748  *  interface.
749  *
750  *  return 0 on success, positive on failure
751  **********************************************************************/
752 
753 static int
754 em_ioctl(struct ifnet *ifp, u_long command, caddr_t data, struct ucred *cr)
755 {
756 	int max_frame_size, mask, error = 0;
757 	struct ifreq *ifr = (struct ifreq *) data;
758 	struct adapter *adapter = ifp->if_softc;
759 
760 	ASSERT_SERIALIZED(adapter->interface_data.ac_if.if_serializer);
761 
762 	if (adapter->in_detach)
763 		goto out;
764 
765 	switch (command) {
766 	case SIOCSIFADDR:
767 	case SIOCGIFADDR:
768 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOCxIFADDR (Get/Set Interface Addr)");
769 		ether_ioctl(ifp, command, data);
770 		break;
771 	case SIOCSIFMTU:
772 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOCSIFMTU (Set Interface MTU)");
773 		switch (adapter->hw.mac_type) {
774 		case em_82571:
775 		case em_82572:
776 			max_frame_size = 10500;
777 			break;
778 		case em_82573:
779 			/* 82573 does not support jumbo frames */
780 			max_frame_size = ETHER_MAX_LEN;
781 			break;
782 		default:
783 			max_frame_size = MAX_JUMBO_FRAME_SIZE;
784 			break;
785 		}
786 		if (ifr->ifr_mtu >
787 			max_frame_size - ETHER_HDR_LEN - ETHER_CRC_LEN) {
788 			error = EINVAL;
789 		} else {
790 			ifp->if_mtu = ifr->ifr_mtu;
791 			adapter->hw.max_frame_size =
792 			ifp->if_mtu + ETHER_HDR_LEN + ETHER_CRC_LEN;
793 			em_init(adapter);
794 		}
795 		break;
796 	case SIOCSIFFLAGS:
797 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOCSIFFLAGS (Set Interface Flags)");
798 		if (ifp->if_flags & IFF_UP) {
799 			if (!(ifp->if_flags & IFF_RUNNING))
800 				em_init(adapter);
801 			em_disable_promisc(adapter);
802 			em_set_promisc(adapter);
803 		} else {
804 			if (ifp->if_flags & IFF_RUNNING)
805 				em_stop(adapter);
806 		}
807 		break;
808 	case SIOCADDMULTI:
809 	case SIOCDELMULTI:
810 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOC(ADD|DEL)MULTI");
811 		if (ifp->if_flags & IFF_RUNNING) {
812 			em_disable_intr(adapter);
813 			em_set_multi(adapter);
814 			if (adapter->hw.mac_type == em_82542_rev2_0)
815 				em_initialize_receive_unit(adapter);
816 			em_enable_intr(adapter);
817 		}
818 		break;
819 	case SIOCSIFMEDIA:
820 	case SIOCGIFMEDIA:
821 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOCxIFMEDIA (Get/Set Interface Media)");
822 		error = ifmedia_ioctl(ifp, ifr, &adapter->media, command);
823 		break;
824 	case SIOCSIFCAP:
825 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOCSIFCAP (Set Capabilities)");
826 		mask = ifr->ifr_reqcap ^ ifp->if_capenable;
827 		if (mask & IFCAP_HWCSUM) {
828 			if (IFCAP_HWCSUM & ifp->if_capenable)
829 				ifp->if_capenable &= ~IFCAP_HWCSUM;
830 			else
831 				ifp->if_capenable |= IFCAP_HWCSUM;
832 			if (ifp->if_flags & IFF_RUNNING)
833 				em_init(adapter);
834 		}
835 		break;
836 	default:
837 		IOCTL_DEBUGOUT1("ioctl received: UNKNOWN (0x%x)", (int)command);
838 		error = EINVAL;
839 	}
840 
841 out:
842 	return(error);
843 }
844 
845 /*********************************************************************
846  *  Watchdog entry point
847  *
848  *  This routine is called whenever hardware quits transmitting.
849  *
850  **********************************************************************/
851 
852 static void
853 em_watchdog(struct ifnet *ifp)
854 {
855 	struct adapter * adapter;
856 	adapter = ifp->if_softc;
857 
858 	/* If we are in this routine because of pause frames, then
859 	 * don't reset the hardware.
860 	 */
861 	if (E1000_READ_REG(&adapter->hw, STATUS) & E1000_STATUS_TXOFF) {
862 		ifp->if_timer = EM_TX_TIMEOUT;
863 		return;
864 	}
865 
866 	if (em_check_for_link(&adapter->hw))
867 		if_printf(ifp, "watchdog timeout -- resetting\n");
868 
869 	ifp->if_flags &= ~IFF_RUNNING;
870 
871 	em_init(adapter);
872 
873 	ifp->if_oerrors++;
874 }
875 
876 /*********************************************************************
877  *  Init entry point
878  *
879  *  This routine is used in two ways. It is used by the stack as
880  *  init entry point in network interface structure. It is also used
881  *  by the driver as a hw/sw initialization routine to get to a
882  *  consistent state.
883  *
884  *  return 0 on success, positive on failure
885  **********************************************************************/
886 
887 static void
888 em_init(void *arg)
889 {
890 	struct adapter *adapter = arg;
891 	uint32_t pba;
892 	struct ifnet *ifp = &adapter->interface_data.ac_if;
893 
894 	INIT_DEBUGOUT("em_init: begin");
895 
896 	em_stop(adapter);
897 
898 	/*
899 	 * Packet Buffer Allocation (PBA)
900 	 * Writing PBA sets the receive portion of the buffer
901 	 * the remainder is used for the transmit buffer.
902 	 */
903 	switch (adapter->hw.mac_type) {
904 	case em_82547:
905 	case em_82547_rev_2: /* 82547: Total Packet Buffer is 40K */
906 		if (adapter->hw.max_frame_size > EM_RXBUFFER_8192)
907 			pba = E1000_PBA_22K; /* 22K for Rx, 18K for Tx */
908 		else
909 			pba = E1000_PBA_30K; /* 30K for Rx, 10K for Tx */
910 
911 		adapter->tx_fifo_head = 0;
912 		adapter->tx_head_addr = pba << EM_TX_HEAD_ADDR_SHIFT;
913 		adapter->tx_fifo_size =
914 			(E1000_PBA_40K - pba) << EM_PBA_BYTES_SHIFT;
915 		break;
916 	case em_82571: /* 82571: Total Packet Buffer is 48K */
917 	case em_82572: /* 82572: Total Packet Buffer is 48K */
918 		pba = E1000_PBA_32K; /* 32K for Rx, 16K for Tx */
919 		break;
920 	case em_82573: /* 82573: Total Packet Buffer is 32K */
921 		/* Jumbo frames not supported */
922 		pba = E1000_PBA_12K; /* 12K for Rx, 20K for Tx */
923 		break;
924 	default:
925 		/* Devices before 82547 had a Packet Buffer of 64K.   */
926 		if(adapter->hw.max_frame_size > EM_RXBUFFER_8192)
927 			pba = E1000_PBA_40K; /* 40K for Rx, 24K for Tx */
928 		else
929 			pba = E1000_PBA_48K; /* 48K for Rx, 16K for Tx */
930 	}
931 
932 	INIT_DEBUGOUT1("em_init: pba=%dK",pba);
933 	E1000_WRITE_REG(&adapter->hw, PBA, pba);
934 
935 	/* Get the latest mac address, User can use a LAA */
936 	bcopy(adapter->interface_data.ac_enaddr, adapter->hw.mac_addr,
937 	      ETHER_ADDR_LEN);
938 
939 	/* Initialize the hardware */
940 	if (em_hardware_init(adapter)) {
941 		if_printf(ifp, "Unable to initialize the hardware\n");
942 		return;
943 	}
944 
945 	em_enable_vlans(adapter);
946 
947 	/* Prepare transmit descriptors and buffers */
948 	if (em_setup_transmit_structures(adapter)) {
949 		if_printf(ifp, "Could not setup transmit structures\n");
950 		em_stop(adapter);
951 		return;
952 	}
953 	em_initialize_transmit_unit(adapter);
954 
955 	/* Setup Multicast table */
956 	em_set_multi(adapter);
957 
958 	/* Prepare receive descriptors and buffers */
959 	if (em_setup_receive_structures(adapter)) {
960 		if_printf(ifp, "Could not setup receive structures\n");
961 		em_stop(adapter);
962 		return;
963 	}
964 	em_initialize_receive_unit(adapter);
965 
966 	/* Don't loose promiscuous settings */
967 	em_set_promisc(adapter);
968 
969 	ifp->if_flags |= IFF_RUNNING;
970 	ifp->if_flags &= ~IFF_OACTIVE;
971 
972 	if (adapter->hw.mac_type >= em_82543) {
973 		if (ifp->if_capenable & IFCAP_TXCSUM)
974 			ifp->if_hwassist = EM_CHECKSUM_FEATURES;
975 		else
976 			ifp->if_hwassist = 0;
977 	}
978 
979 	callout_reset(&adapter->timer, hz, em_local_timer, adapter);
980 	em_clear_hw_cntrs(&adapter->hw);
981 	em_enable_intr(adapter);
982 
983 	/* Don't reset the phy next time init gets called */
984 	adapter->hw.phy_reset_disable = TRUE;
985 }
986 
987 #ifdef DEVICE_POLLING
988 
989 static void
990 em_poll(struct ifnet *ifp, enum poll_cmd cmd, int count)
991 {
992 	struct adapter *adapter = ifp->if_softc;
993 	uint32_t reg_icr;
994 
995 	logif(poll_beg);
996 
997 	ASSERT_SERIALIZED(ifp->if_serializer);
998 
999 	switch(cmd) {
1000 	case POLL_REGISTER:
1001 		em_disable_intr(adapter);
1002 		break;
1003 	case POLL_DEREGISTER:
1004 		em_enable_intr(adapter);
1005 		break;
1006 	case POLL_AND_CHECK_STATUS:
1007 		reg_icr = E1000_READ_REG(&adapter->hw, ICR);
1008 		if (reg_icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC)) {
1009 			callout_stop(&adapter->timer);
1010 			adapter->hw.get_link_status = 1;
1011 			em_check_for_link(&adapter->hw);
1012 			em_print_link_status(adapter);
1013 			callout_reset(&adapter->timer, hz, em_local_timer,
1014 				      adapter);
1015 		}
1016 		/* fall through */
1017 	case POLL_ONLY:
1018 		if (ifp->if_flags & IFF_RUNNING) {
1019 			em_process_receive_interrupts(adapter, count);
1020 			em_clean_transmit_interrupts(adapter);
1021 		}
1022 		if (ifp->if_flags & IFF_RUNNING) {
1023 			if (!ifq_is_empty(&ifp->if_snd))
1024 				em_start(ifp);
1025 		}
1026 		break;
1027 	}
1028 	logif(poll_end);
1029 }
1030 
1031 #endif /* DEVICE_POLLING */
1032 
1033 /*********************************************************************
1034  *
1035  *  Interrupt Service routine
1036  *
1037  **********************************************************************/
1038 static void
1039 em_intr(void *arg)
1040 {
1041 	uint32_t reg_icr;
1042 	struct ifnet *ifp;
1043 	struct adapter *adapter = arg;
1044 
1045 	ifp = &adapter->interface_data.ac_if;
1046 
1047 	logif(intr_beg);
1048 	ASSERT_SERIALIZED(ifp->if_serializer);
1049 
1050 	reg_icr = E1000_READ_REG(&adapter->hw, ICR);
1051 	if (!reg_icr) {
1052 		logif(intr_end);
1053 		return;
1054 	}
1055 
1056 	/* Link status change */
1057 	if (reg_icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC)) {
1058 		callout_stop(&adapter->timer);
1059 		adapter->hw.get_link_status = 1;
1060 		em_check_for_link(&adapter->hw);
1061 		em_print_link_status(adapter);
1062 		callout_reset(&adapter->timer, hz, em_local_timer, adapter);
1063 	}
1064 
1065 	/*
1066 	 * note: do not attempt to improve efficiency by looping.  This
1067 	 * only results in unnecessary piecemeal collection of received
1068 	 * packets and unnecessary piecemeal cleanups of the transmit ring.
1069 	 */
1070 	if (ifp->if_flags & IFF_RUNNING) {
1071 		em_process_receive_interrupts(adapter, -1);
1072 		em_clean_transmit_interrupts(adapter);
1073 	}
1074 
1075 	if ((ifp->if_flags & IFF_RUNNING) && !ifq_is_empty(&ifp->if_snd))
1076 		em_start(ifp);
1077 	logif(intr_end);
1078 }
1079 
1080 /*********************************************************************
1081  *
1082  *  Media Ioctl callback
1083  *
1084  *  This routine is called whenever the user queries the status of
1085  *  the interface using ifconfig.
1086  *
1087  **********************************************************************/
1088 static void
1089 em_media_status(struct ifnet *ifp, struct ifmediareq *ifmr)
1090 {
1091 	struct adapter * adapter = ifp->if_softc;
1092 
1093 	INIT_DEBUGOUT("em_media_status: begin");
1094 
1095 	ASSERT_SERIALIZED(ifp->if_serializer);
1096 
1097 	em_check_for_link(&adapter->hw);
1098 	if (E1000_READ_REG(&adapter->hw, STATUS) & E1000_STATUS_LU) {
1099 		if (adapter->link_active == 0) {
1100 			em_get_speed_and_duplex(&adapter->hw,
1101 						&adapter->link_speed,
1102 						&adapter->link_duplex);
1103 			adapter->link_active = 1;
1104 		}
1105 	} else {
1106 		if (adapter->link_active == 1) {
1107 			adapter->link_speed = 0;
1108 			adapter->link_duplex = 0;
1109 			adapter->link_active = 0;
1110 		}
1111 	}
1112 
1113 	ifmr->ifm_status = IFM_AVALID;
1114 	ifmr->ifm_active = IFM_ETHER;
1115 
1116 	if (!adapter->link_active)
1117 		return;
1118 
1119 	ifmr->ifm_status |= IFM_ACTIVE;
1120 
1121 	if (adapter->hw.media_type == em_media_type_fiber) {
1122 		ifmr->ifm_active |= IFM_1000_SX | IFM_FDX;
1123 	} else {
1124 		switch (adapter->link_speed) {
1125 		case 10:
1126 			ifmr->ifm_active |= IFM_10_T;
1127 			break;
1128 		case 100:
1129 			ifmr->ifm_active |= IFM_100_TX;
1130 			break;
1131 		case 1000:
1132 			ifmr->ifm_active |= IFM_1000_T;
1133 			break;
1134 		}
1135 		if (adapter->link_duplex == FULL_DUPLEX)
1136 			ifmr->ifm_active |= IFM_FDX;
1137 		else
1138 			ifmr->ifm_active |= IFM_HDX;
1139 	}
1140 }
1141 
1142 /*********************************************************************
1143  *
1144  *  Media Ioctl callback
1145  *
1146  *  This routine is called when the user changes speed/duplex using
1147  *  media/mediopt option with ifconfig.
1148  *
1149  **********************************************************************/
1150 static int
1151 em_media_change(struct ifnet *ifp)
1152 {
1153 	struct adapter * adapter = ifp->if_softc;
1154 	struct ifmedia  *ifm = &adapter->media;
1155 
1156 	INIT_DEBUGOUT("em_media_change: begin");
1157 
1158 	if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER)
1159 		return(EINVAL);
1160 
1161 	ASSERT_SERIALIZED(ifp->if_serializer);
1162 
1163 	switch (IFM_SUBTYPE(ifm->ifm_media)) {
1164 	case IFM_AUTO:
1165 		adapter->hw.autoneg = DO_AUTO_NEG;
1166 		adapter->hw.autoneg_advertised = AUTONEG_ADV_DEFAULT;
1167 		break;
1168 	case IFM_1000_SX:
1169 	case IFM_1000_T:
1170 		adapter->hw.autoneg = DO_AUTO_NEG;
1171 		adapter->hw.autoneg_advertised = ADVERTISE_1000_FULL;
1172 		break;
1173 	case IFM_100_TX:
1174 		adapter->hw.autoneg = FALSE;
1175 		adapter->hw.autoneg_advertised = 0;
1176 		if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
1177 			adapter->hw.forced_speed_duplex = em_100_full;
1178 		else
1179 			adapter->hw.forced_speed_duplex	= em_100_half;
1180 		break;
1181 	case IFM_10_T:
1182 		adapter->hw.autoneg = FALSE;
1183 		adapter->hw.autoneg_advertised = 0;
1184 		if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
1185 			adapter->hw.forced_speed_duplex = em_10_full;
1186 		else
1187 			adapter->hw.forced_speed_duplex	= em_10_half;
1188 		break;
1189 	default:
1190 		if_printf(ifp, "Unsupported media type\n");
1191 	}
1192 	/*
1193 	 * As the speed/duplex settings may have changed we need to
1194 	 * reset the PHY.
1195 	 */
1196 	adapter->hw.phy_reset_disable = FALSE;
1197 
1198 	em_init(adapter);
1199 
1200 	return(0);
1201 }
1202 
1203 static void
1204 em_tx_cb(void *arg, bus_dma_segment_t *seg, int nsegs, bus_size_t mapsize,
1205 	 int error)
1206 {
1207 	struct em_q *q = arg;
1208 
1209 	if (error)
1210 		return;
1211 	KASSERT(nsegs <= EM_MAX_SCATTER,
1212 		("Too many DMA segments returned when mapping tx packet"));
1213 	q->nsegs = nsegs;
1214 	bcopy(seg, q->segs, nsegs * sizeof(seg[0]));
1215 }
1216 
1217 /*********************************************************************
1218  *
1219  *  This routine maps the mbufs to tx descriptors.
1220  *
1221  *  return 0 on success, positive on failure
1222  **********************************************************************/
1223 static int
1224 em_encap(struct adapter *adapter, struct mbuf *m_head)
1225 {
1226 	uint32_t txd_upper;
1227 	uint32_t txd_lower, txd_used = 0, txd_saved = 0;
1228 	int i, j, error;
1229 	uint64_t address;
1230 
1231 	/* For 82544 Workaround */
1232 	DESC_ARRAY desc_array;
1233 	uint32_t array_elements;
1234 	uint32_t counter;
1235 
1236 	struct ifvlan *ifv = NULL;
1237 	struct em_q q;
1238         struct em_buffer *tx_buffer = NULL;
1239         struct em_tx_desc *current_tx_desc = NULL;
1240         struct ifnet *ifp = &adapter->interface_data.ac_if;
1241 
1242 	/*
1243 	 * Force a cleanup if number of TX descriptors
1244 	 * available hits the threshold
1245 	 */
1246 	if (adapter->num_tx_desc_avail <= EM_TX_CLEANUP_THRESHOLD) {
1247 		em_clean_transmit_interrupts(adapter);
1248 		if (adapter->num_tx_desc_avail <= EM_TX_CLEANUP_THRESHOLD) {
1249 			adapter->no_tx_desc_avail1++;
1250 			return(ENOBUFS);
1251 		}
1252 	}
1253 	/*
1254 	 * Map the packet for DMA.
1255 	 */
1256 	if (bus_dmamap_create(adapter->txtag, BUS_DMA_NOWAIT, &q.map)) {
1257 		adapter->no_tx_map_avail++;
1258 		return(ENOMEM);
1259 	}
1260 	error = bus_dmamap_load_mbuf(adapter->txtag, q.map, m_head, em_tx_cb,
1261 				     &q, BUS_DMA_NOWAIT);
1262 	if (error != 0) {
1263 		adapter->no_tx_dma_setup++;
1264 		bus_dmamap_destroy(adapter->txtag, q.map);
1265 		return(error);
1266 	}
1267 	KASSERT(q.nsegs != 0, ("em_encap: empty packet"));
1268 
1269 	if (q.nsegs > adapter->num_tx_desc_avail) {
1270 		adapter->no_tx_desc_avail2++;
1271 		bus_dmamap_unload(adapter->txtag, q.map);
1272 		bus_dmamap_destroy(adapter->txtag, q.map);
1273 		return(ENOBUFS);
1274 	}
1275 
1276 	if (ifp->if_hwassist > 0) {
1277 		em_transmit_checksum_setup(adapter,  m_head,
1278 					   &txd_upper, &txd_lower);
1279 	} else {
1280 		txd_upper = txd_lower = 0;
1281 	}
1282 
1283 	/* Find out if we are in vlan mode */
1284 	if ((m_head->m_flags & (M_PROTO1|M_PKTHDR)) == (M_PROTO1|M_PKTHDR) &&
1285 	    m_head->m_pkthdr.rcvif != NULL &&
1286 	    m_head->m_pkthdr.rcvif->if_type == IFT_L2VLAN)
1287 		ifv = m_head->m_pkthdr.rcvif->if_softc;
1288 
1289 	i = adapter->next_avail_tx_desc;
1290 	if (adapter->pcix_82544) {
1291 		txd_saved = i;
1292 		txd_used = 0;
1293 	}
1294 	for (j = 0; j < q.nsegs; j++) {
1295 		/* If adapter is 82544 and on PCIX bus */
1296 		if(adapter->pcix_82544) {
1297 			array_elements = 0;
1298 			address = htole64(q.segs[j].ds_addr);
1299 			/*
1300 			 * Check the Address and Length combination and
1301 			 * split the data accordingly
1302 			 */
1303 			array_elements = em_fill_descriptors(address,
1304 							     htole32(q.segs[j].ds_len),
1305 							     &desc_array);
1306 			for (counter = 0; counter < array_elements; counter++) {
1307 				if (txd_used == adapter->num_tx_desc_avail) {
1308 					adapter->next_avail_tx_desc = txd_saved;
1309 					adapter->no_tx_desc_avail2++;
1310 					bus_dmamap_unload(adapter->txtag, q.map);
1311 					bus_dmamap_destroy(adapter->txtag, q.map);
1312 					return(ENOBUFS);
1313 				}
1314 				tx_buffer = &adapter->tx_buffer_area[i];
1315 				current_tx_desc = &adapter->tx_desc_base[i];
1316 				current_tx_desc->buffer_addr = htole64(
1317 				desc_array.descriptor[counter].address);
1318 				current_tx_desc->lower.data = htole32(
1319 				(adapter->txd_cmd | txd_lower |
1320 				(uint16_t)desc_array.descriptor[counter].length));
1321 				current_tx_desc->upper.data = htole32((txd_upper));
1322 				if (++i == adapter->num_tx_desc)
1323 					i = 0;
1324 
1325 				tx_buffer->m_head = NULL;
1326 				txd_used++;
1327 			}
1328 		} else {
1329 			tx_buffer = &adapter->tx_buffer_area[i];
1330 			current_tx_desc = &adapter->tx_desc_base[i];
1331 
1332 			current_tx_desc->buffer_addr = htole64(q.segs[j].ds_addr);
1333 			current_tx_desc->lower.data = htole32(
1334 				adapter->txd_cmd | txd_lower | q.segs[j].ds_len);
1335 			current_tx_desc->upper.data = htole32(txd_upper);
1336 
1337 			if (++i == adapter->num_tx_desc)
1338 				i = 0;
1339 
1340 			tx_buffer->m_head = NULL;
1341 		}
1342 	}
1343 
1344 	adapter->next_avail_tx_desc = i;
1345 	if (adapter->pcix_82544)
1346 		adapter->num_tx_desc_avail -= txd_used;
1347 	else
1348 		adapter->num_tx_desc_avail -= q.nsegs;
1349 
1350 	if (ifv != NULL) {
1351 		/* Set the vlan id */
1352 		current_tx_desc->upper.fields.special = htole16(ifv->ifv_tag);
1353 
1354 		/* Tell hardware to add tag */
1355 		current_tx_desc->lower.data |= htole32(E1000_TXD_CMD_VLE);
1356 	}
1357 
1358 	tx_buffer->m_head = m_head;
1359 	tx_buffer->map = q.map;
1360 	bus_dmamap_sync(adapter->txtag, q.map, BUS_DMASYNC_PREWRITE);
1361 
1362 	/*
1363 	 * Last Descriptor of Packet needs End Of Packet (EOP)
1364 	 */
1365 	current_tx_desc->lower.data |= htole32(E1000_TXD_CMD_EOP);
1366 
1367 	bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
1368 			BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
1369 
1370 	/*
1371 	 * Advance the Transmit Descriptor Tail (Tdt), this tells the E1000
1372 	 * that this frame is available to transmit.
1373 	 */
1374 	if (adapter->hw.mac_type == em_82547 &&
1375 	    adapter->link_duplex == HALF_DUPLEX) {
1376 		em_82547_move_tail_serialized(adapter);
1377 	} else {
1378 		E1000_WRITE_REG(&adapter->hw, TDT, i);
1379 		if (adapter->hw.mac_type == em_82547) {
1380 			em_82547_update_fifo_head(adapter,
1381 						  m_head->m_pkthdr.len);
1382 		}
1383 	}
1384 
1385 	return(0);
1386 }
1387 
1388 /*********************************************************************
1389  *
1390  * 82547 workaround to avoid controller hang in half-duplex environment.
1391  * The workaround is to avoid queuing a large packet that would span
1392  * the internal Tx FIFO ring boundary. We need to reset the FIFO pointers
1393  * in this case. We do that only when FIFO is queiced.
1394  *
1395  **********************************************************************/
1396 static void
1397 em_82547_move_tail(void *arg)
1398 {
1399 	struct adapter *adapter = arg;
1400 
1401 	lwkt_serialize_enter(adapter->interface_data.ac_if.if_serializer);
1402 	em_82547_move_tail_serialized(arg);
1403 	lwkt_serialize_exit(adapter->interface_data.ac_if.if_serializer);
1404 }
1405 
1406 static void
1407 em_82547_move_tail_serialized(void *arg)
1408 {
1409 	struct adapter *adapter = arg;
1410 	uint16_t hw_tdt;
1411 	uint16_t sw_tdt;
1412 	struct em_tx_desc *tx_desc;
1413 	uint16_t length = 0;
1414 	boolean_t eop = 0;
1415 
1416 	hw_tdt = E1000_READ_REG(&adapter->hw, TDT);
1417 	sw_tdt = adapter->next_avail_tx_desc;
1418 
1419 	while (hw_tdt != sw_tdt) {
1420 		tx_desc = &adapter->tx_desc_base[hw_tdt];
1421 		length += tx_desc->lower.flags.length;
1422 		eop = tx_desc->lower.data & E1000_TXD_CMD_EOP;
1423 		if(++hw_tdt == adapter->num_tx_desc)
1424 			hw_tdt = 0;
1425 
1426 		if(eop) {
1427 			if (em_82547_fifo_workaround(adapter, length)) {
1428 				adapter->tx_fifo_wrk_cnt++;
1429 				callout_reset(&adapter->tx_fifo_timer, 1,
1430 					em_82547_move_tail, adapter);
1431 				break;
1432 			}
1433 			E1000_WRITE_REG(&adapter->hw, TDT, hw_tdt);
1434 			em_82547_update_fifo_head(adapter, length);
1435 			length = 0;
1436 		}
1437 	}
1438 }
1439 
1440 static int
1441 em_82547_fifo_workaround(struct adapter *adapter, int len)
1442 {
1443 	int fifo_space, fifo_pkt_len;
1444 
1445 	fifo_pkt_len = EM_ROUNDUP(len + EM_FIFO_HDR, EM_FIFO_HDR);
1446 
1447 	if (adapter->link_duplex == HALF_DUPLEX) {
1448 		fifo_space = adapter->tx_fifo_size - adapter->tx_fifo_head;
1449 
1450 		if (fifo_pkt_len >= (EM_82547_PKT_THRESH + fifo_space)) {
1451 			if (em_82547_tx_fifo_reset(adapter))
1452 				return(0);
1453 			else
1454 				return(1);
1455 		}
1456 	}
1457 
1458 	return(0);
1459 }
1460 
1461 static void
1462 em_82547_update_fifo_head(struct adapter *adapter, int len)
1463 {
1464 	int fifo_pkt_len = EM_ROUNDUP(len + EM_FIFO_HDR, EM_FIFO_HDR);
1465 
1466 	/* tx_fifo_head is always 16 byte aligned */
1467 	adapter->tx_fifo_head += fifo_pkt_len;
1468 	if (adapter->tx_fifo_head >= adapter->tx_fifo_size)
1469 		adapter->tx_fifo_head -= adapter->tx_fifo_size;
1470 }
1471 
1472 static int
1473 em_82547_tx_fifo_reset(struct adapter *adapter)
1474 {
1475 	uint32_t tctl;
1476 
1477 	if ( (E1000_READ_REG(&adapter->hw, TDT) ==
1478 	      E1000_READ_REG(&adapter->hw, TDH)) &&
1479 	     (E1000_READ_REG(&adapter->hw, TDFT) ==
1480 	      E1000_READ_REG(&adapter->hw, TDFH)) &&
1481 	     (E1000_READ_REG(&adapter->hw, TDFTS) ==
1482 	      E1000_READ_REG(&adapter->hw, TDFHS)) &&
1483 	     (E1000_READ_REG(&adapter->hw, TDFPC) == 0)) {
1484 
1485 		/* Disable TX unit */
1486 		tctl = E1000_READ_REG(&adapter->hw, TCTL);
1487 		E1000_WRITE_REG(&adapter->hw, TCTL, tctl & ~E1000_TCTL_EN);
1488 
1489 		/* Reset FIFO pointers */
1490 		E1000_WRITE_REG(&adapter->hw, TDFT,  adapter->tx_head_addr);
1491 		E1000_WRITE_REG(&adapter->hw, TDFH,  adapter->tx_head_addr);
1492 		E1000_WRITE_REG(&adapter->hw, TDFTS, adapter->tx_head_addr);
1493 		E1000_WRITE_REG(&adapter->hw, TDFHS, adapter->tx_head_addr);
1494 
1495 		/* Re-enable TX unit */
1496 		E1000_WRITE_REG(&adapter->hw, TCTL, tctl);
1497 		E1000_WRITE_FLUSH(&adapter->hw);
1498 
1499 		adapter->tx_fifo_head = 0;
1500 		adapter->tx_fifo_reset_cnt++;
1501 
1502 		return(TRUE);
1503 	} else {
1504 		return(FALSE);
1505 	}
1506 }
1507 
1508 static void
1509 em_set_promisc(struct adapter *adapter)
1510 {
1511 	uint32_t reg_rctl, ctrl;
1512 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1513 
1514 	reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1515 	ctrl = E1000_READ_REG(&adapter->hw, CTRL);
1516 
1517 	if (ifp->if_flags & IFF_PROMISC) {
1518 		reg_rctl |= (E1000_RCTL_UPE | E1000_RCTL_MPE);
1519 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1520 
1521 		/*
1522 		 * Disable VLAN stripping in promiscous mode.
1523 		 * This enables bridging of vlan tagged frames to occur
1524 		 * and also allows vlan tags to be seen in tcpdump.
1525 		 */
1526 		ctrl &= ~E1000_CTRL_VME;
1527 		E1000_WRITE_REG(&adapter->hw, CTRL, ctrl);
1528 	} else if (ifp->if_flags & IFF_ALLMULTI) {
1529 		reg_rctl |= E1000_RCTL_MPE;
1530 		reg_rctl &= ~E1000_RCTL_UPE;
1531 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1532 	}
1533 }
1534 
1535 static void
1536 em_disable_promisc(struct adapter *adapter)
1537 {
1538 	uint32_t reg_rctl;
1539 
1540 	reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1541 
1542 	reg_rctl &= (~E1000_RCTL_UPE);
1543 	reg_rctl &= (~E1000_RCTL_MPE);
1544 	E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1545 
1546 	em_enable_vlans(adapter);
1547 }
1548 
1549 /*********************************************************************
1550  *  Multicast Update
1551  *
1552  *  This routine is called whenever multicast address list is updated.
1553  *
1554  **********************************************************************/
1555 
1556 static void
1557 em_set_multi(struct adapter *adapter)
1558 {
1559 	uint32_t reg_rctl = 0;
1560 	uint8_t mta[MAX_NUM_MULTICAST_ADDRESSES * ETH_LENGTH_OF_ADDRESS];
1561 	struct ifmultiaddr *ifma;
1562 	int mcnt = 0;
1563 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1564 
1565 	IOCTL_DEBUGOUT("em_set_multi: begin");
1566 
1567 	if (adapter->hw.mac_type == em_82542_rev2_0) {
1568 		reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1569 		if (adapter->hw.pci_cmd_word & CMD_MEM_WRT_INVALIDATE)
1570 			em_pci_clear_mwi(&adapter->hw);
1571 		reg_rctl |= E1000_RCTL_RST;
1572 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1573 		msec_delay(5);
1574 	}
1575 
1576 	LIST_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
1577 		if (ifma->ifma_addr->sa_family != AF_LINK)
1578 			continue;
1579 
1580 		if (mcnt == MAX_NUM_MULTICAST_ADDRESSES)
1581 			break;
1582 
1583 		bcopy(LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
1584 		      &mta[mcnt*ETH_LENGTH_OF_ADDRESS], ETH_LENGTH_OF_ADDRESS);
1585 		mcnt++;
1586 	}
1587 
1588 	if (mcnt >= MAX_NUM_MULTICAST_ADDRESSES) {
1589 		reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1590 		reg_rctl |= E1000_RCTL_MPE;
1591 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1592 	} else {
1593 		em_mc_addr_list_update(&adapter->hw, mta, mcnt, 0, 1);
1594 	}
1595 
1596 	if (adapter->hw.mac_type == em_82542_rev2_0) {
1597 		reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1598 		reg_rctl &= ~E1000_RCTL_RST;
1599 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1600 		msec_delay(5);
1601 		if (adapter->hw.pci_cmd_word & CMD_MEM_WRT_INVALIDATE)
1602                         em_pci_set_mwi(&adapter->hw);
1603 	}
1604 }
1605 
1606 /*********************************************************************
1607  *  Timer routine
1608  *
1609  *  This routine checks for link status and updates statistics.
1610  *
1611  **********************************************************************/
1612 
1613 static void
1614 em_local_timer(void *arg)
1615 {
1616 	struct ifnet *ifp;
1617 	struct adapter *adapter = arg;
1618 	ifp = &adapter->interface_data.ac_if;
1619 
1620 	lwkt_serialize_enter(ifp->if_serializer);
1621 
1622 	em_check_for_link(&adapter->hw);
1623 	em_print_link_status(adapter);
1624 	em_update_stats_counters(adapter);
1625 	if (em_display_debug_stats && ifp->if_flags & IFF_RUNNING)
1626 		em_print_hw_stats(adapter);
1627 	em_smartspeed(adapter);
1628 
1629 	callout_reset(&adapter->timer, hz, em_local_timer, adapter);
1630 
1631 	lwkt_serialize_exit(ifp->if_serializer);
1632 }
1633 
1634 static void
1635 em_print_link_status(struct adapter *adapter)
1636 {
1637 	if (E1000_READ_REG(&adapter->hw, STATUS) & E1000_STATUS_LU) {
1638 		if (adapter->link_active == 0) {
1639 			em_get_speed_and_duplex(&adapter->hw,
1640 						&adapter->link_speed,
1641 						&adapter->link_duplex);
1642 			device_printf(adapter->dev, "Link is up %d Mbps %s\n",
1643 			       adapter->link_speed,
1644 			       ((adapter->link_duplex == FULL_DUPLEX) ?
1645 				"Full Duplex" : "Half Duplex"));
1646 			adapter->link_active = 1;
1647 			adapter->smartspeed = 0;
1648 		}
1649 	} else {
1650 		if (adapter->link_active == 1) {
1651 			adapter->link_speed = 0;
1652 			adapter->link_duplex = 0;
1653 			device_printf(adapter->dev, "Link is Down\n");
1654 			adapter->link_active = 0;
1655 		}
1656 	}
1657 }
1658 
1659 /*********************************************************************
1660  *
1661  *  This routine disables all traffic on the adapter by issuing a
1662  *  global reset on the MAC and deallocates TX/RX buffers.
1663  *
1664  **********************************************************************/
1665 
1666 static void
1667 em_stop(void *arg)
1668 {
1669 	struct ifnet   *ifp;
1670 	struct adapter * adapter = arg;
1671 	ifp = &adapter->interface_data.ac_if;
1672 
1673 	INIT_DEBUGOUT("em_stop: begin");
1674 	em_disable_intr(adapter);
1675 	em_reset_hw(&adapter->hw);
1676 	callout_stop(&adapter->timer);
1677 	callout_stop(&adapter->tx_fifo_timer);
1678 	em_free_transmit_structures(adapter);
1679 	em_free_receive_structures(adapter);
1680 
1681 	/* Tell the stack that the interface is no longer active */
1682 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
1683 	ifp->if_timer = 0;
1684 }
1685 
1686 /*********************************************************************
1687  *
1688  *  Determine hardware revision.
1689  *
1690  **********************************************************************/
1691 static void
1692 em_identify_hardware(struct adapter * adapter)
1693 {
1694 	device_t dev = adapter->dev;
1695 
1696 	/* Make sure our PCI config space has the necessary stuff set */
1697 	adapter->hw.pci_cmd_word = pci_read_config(dev, PCIR_COMMAND, 2);
1698 	if (!((adapter->hw.pci_cmd_word & PCIM_CMD_BUSMASTEREN) &&
1699 	      (adapter->hw.pci_cmd_word & PCIM_CMD_MEMEN))) {
1700 		device_printf(dev, "Memory Access and/or Bus Master bits were not set!\n");
1701 		adapter->hw.pci_cmd_word |=
1702 		(PCIM_CMD_BUSMASTEREN | PCIM_CMD_MEMEN);
1703 		pci_write_config(dev, PCIR_COMMAND, adapter->hw.pci_cmd_word, 2);
1704 	}
1705 
1706 	/* Save off the information about this board */
1707 	adapter->hw.vendor_id = pci_get_vendor(dev);
1708 	adapter->hw.device_id = pci_get_device(dev);
1709 	adapter->hw.revision_id = pci_get_revid(dev);
1710 	adapter->hw.subsystem_vendor_id = pci_get_subvendor(dev);
1711 	adapter->hw.subsystem_id = pci_get_subdevice(dev);
1712 
1713 	/* Identify the MAC */
1714 	if (em_set_mac_type(&adapter->hw))
1715 		device_printf(dev, "Unknown MAC Type\n");
1716 
1717 	if (adapter->hw.mac_type == em_82541 ||
1718 	    adapter->hw.mac_type == em_82541_rev_2 ||
1719 	    adapter->hw.mac_type == em_82547 ||
1720 	    adapter->hw.mac_type == em_82547_rev_2)
1721 		adapter->hw.phy_init_script = TRUE;
1722 }
1723 
1724 /*********************************************************************
1725  *
1726  *  Initialize the hardware to a configuration as specified by the
1727  *  adapter structure. The controller is reset, the EEPROM is
1728  *  verified, the MAC address is set, then the shared initialization
1729  *  routines are called.
1730  *
1731  **********************************************************************/
1732 static int
1733 em_hardware_init(struct adapter *adapter)
1734 {
1735 	uint16_t	rx_buffer_size;
1736 
1737 	INIT_DEBUGOUT("em_hardware_init: begin");
1738 	/* Issue a global reset */
1739 	em_reset_hw(&adapter->hw);
1740 
1741 	/* When hardware is reset, fifo_head is also reset */
1742 	adapter->tx_fifo_head = 0;
1743 
1744 	/* Make sure we have a good EEPROM before we read from it */
1745 	if (em_validate_eeprom_checksum(&adapter->hw) < 0) {
1746 		device_printf(adapter->dev,
1747 			      "The EEPROM Checksum Is Not Valid\n");
1748 		return(EIO);
1749 	}
1750 
1751 	if (em_read_part_num(&adapter->hw, &(adapter->part_num)) < 0) {
1752 		device_printf(adapter->dev,
1753 			      "EEPROM read error while reading part number\n");
1754 		return(EIO);
1755 	}
1756 
1757 	/*
1758 	 * These parameters control the automatic generation (Tx) and
1759 	 * response(Rx) to Ethernet PAUSE frames.
1760 	 * - High water mark should allow for at least two frames to be
1761 	 *   received after sending an XOFF.
1762 	 * - Low water mark works best when it is very near the high water mark.
1763 	 *   This allows the receiver to restart by sending XON when it has
1764 	 *   drained a bit.  Here we use an arbitary value of 1500 which will
1765 	 *   restart after one full frame is pulled from the buffer.  There
1766 	 *   could be several smaller frames in the buffer and if so they will
1767 	 *   not trigger the XON until their total number reduces the buffer
1768 	 *   by 1500.
1769 	 * - The pause time is fairly large at 1000 x 512ns = 512 usec.
1770 	 */
1771 	rx_buffer_size = ((E1000_READ_REG(&adapter->hw, PBA) & 0xffff) << 10);
1772 
1773 	adapter->hw.fc_high_water =
1774 	    rx_buffer_size - EM_ROUNDUP(1 * adapter->hw.max_frame_size, 1024);
1775 	adapter->hw.fc_low_water = adapter->hw.fc_high_water - 1500;
1776 	adapter->hw.fc_pause_time = 1000;
1777 	adapter->hw.fc_send_xon = TRUE;
1778 	adapter->hw.fc = em_fc_full;
1779 
1780 	if (em_init_hw(&adapter->hw) < 0) {
1781 		device_printf(adapter->dev, "Hardware Initialization Failed");
1782 		return(EIO);
1783 	}
1784 
1785 	em_check_for_link(&adapter->hw);
1786 	if (E1000_READ_REG(&adapter->hw, STATUS) & E1000_STATUS_LU)
1787 		adapter->link_active = 1;
1788 	else
1789 		adapter->link_active = 0;
1790 
1791 	if (adapter->link_active) {
1792 		em_get_speed_and_duplex(&adapter->hw,
1793 					&adapter->link_speed,
1794 					&adapter->link_duplex);
1795 	} else {
1796 		adapter->link_speed = 0;
1797 		adapter->link_duplex = 0;
1798 	}
1799 
1800 	return(0);
1801 }
1802 
1803 /*********************************************************************
1804  *
1805  *  Setup networking device structure and register an interface.
1806  *
1807  **********************************************************************/
1808 static void
1809 em_setup_interface(device_t dev, struct adapter *adapter)
1810 {
1811 	struct ifnet   *ifp;
1812 	INIT_DEBUGOUT("em_setup_interface: begin");
1813 
1814 	ifp = &adapter->interface_data.ac_if;
1815 	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
1816 	ifp->if_mtu = ETHERMTU;
1817 	ifp->if_baudrate = 1000000000;
1818 	ifp->if_init =  em_init;
1819 	ifp->if_softc = adapter;
1820 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
1821 	ifp->if_ioctl = em_ioctl;
1822 	ifp->if_start = em_start;
1823 #ifdef DEVICE_POLLING
1824 	ifp->if_poll = em_poll;
1825 #endif
1826 	ifp->if_watchdog = em_watchdog;
1827 	ifq_set_maxlen(&ifp->if_snd, adapter->num_tx_desc - 1);
1828 	ifq_set_ready(&ifp->if_snd);
1829 
1830 	if (adapter->hw.mac_type >= em_82543)
1831 		ifp->if_capabilities |= IFCAP_HWCSUM;
1832 
1833 	ifp->if_capenable = ifp->if_capabilities;
1834 
1835 	ether_ifattach(ifp, adapter->hw.mac_addr, NULL);
1836 
1837 	/*
1838 	 * Tell the upper layer(s) we support long frames.
1839 	 */
1840 	ifp->if_data.ifi_hdrlen = sizeof(struct ether_vlan_header);
1841         ifp->if_capabilities |= IFCAP_VLAN_HWTAGGING | IFCAP_VLAN_MTU;
1842 
1843 	/*
1844 	 * Specify the media types supported by this adapter and register
1845 	 * callbacks to update media and link information
1846 	 */
1847 	ifmedia_init(&adapter->media, IFM_IMASK, em_media_change,
1848 		     em_media_status);
1849 	if (adapter->hw.media_type == em_media_type_fiber) {
1850 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_1000_SX | IFM_FDX,
1851 			    0, NULL);
1852 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_1000_SX,
1853 			    0, NULL);
1854 	} else {
1855 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_10_T, 0, NULL);
1856 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_10_T | IFM_FDX,
1857 			    0, NULL);
1858 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_100_TX,
1859 			    0, NULL);
1860 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_100_TX | IFM_FDX,
1861 			    0, NULL);
1862 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_1000_T | IFM_FDX,
1863 			    0, NULL);
1864 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_1000_T, 0, NULL);
1865 	}
1866 	ifmedia_add(&adapter->media, IFM_ETHER | IFM_AUTO, 0, NULL);
1867 	ifmedia_set(&adapter->media, IFM_ETHER | IFM_AUTO);
1868 }
1869 
1870 /*********************************************************************
1871  *
1872  *  Workaround for SmartSpeed on 82541 and 82547 controllers
1873  *
1874  **********************************************************************/
1875 static void
1876 em_smartspeed(struct adapter *adapter)
1877 {
1878 	uint16_t phy_tmp;
1879 
1880 	if (adapter->link_active || (adapter->hw.phy_type != em_phy_igp) ||
1881 	    !adapter->hw.autoneg ||
1882 	    !(adapter->hw.autoneg_advertised & ADVERTISE_1000_FULL))
1883 		return;
1884 
1885 	if (adapter->smartspeed == 0) {
1886 		/*
1887 		 * If Master/Slave config fault is asserted twice,
1888 		 * we assume back-to-back.
1889 		 */
1890 		em_read_phy_reg(&adapter->hw, PHY_1000T_STATUS, &phy_tmp);
1891 		if (!(phy_tmp & SR_1000T_MS_CONFIG_FAULT))
1892 			return;
1893 		em_read_phy_reg(&adapter->hw, PHY_1000T_STATUS, &phy_tmp);
1894 		if (phy_tmp & SR_1000T_MS_CONFIG_FAULT) {
1895 			em_read_phy_reg(&adapter->hw, PHY_1000T_CTRL,
1896 					&phy_tmp);
1897 			if (phy_tmp & CR_1000T_MS_ENABLE) {
1898 				phy_tmp &= ~CR_1000T_MS_ENABLE;
1899 				em_write_phy_reg(&adapter->hw,
1900 						 PHY_1000T_CTRL, phy_tmp);
1901 				adapter->smartspeed++;
1902 				if (adapter->hw.autoneg &&
1903 				    !em_phy_setup_autoneg(&adapter->hw) &&
1904 				    !em_read_phy_reg(&adapter->hw, PHY_CTRL,
1905 						     &phy_tmp)) {
1906 					phy_tmp |= (MII_CR_AUTO_NEG_EN |
1907 						    MII_CR_RESTART_AUTO_NEG);
1908 					em_write_phy_reg(&adapter->hw,
1909 							 PHY_CTRL, phy_tmp);
1910 				}
1911 			}
1912 		}
1913                 return;
1914 	} else if (adapter->smartspeed == EM_SMARTSPEED_DOWNSHIFT) {
1915 		/* If still no link, perhaps using 2/3 pair cable */
1916 		em_read_phy_reg(&adapter->hw, PHY_1000T_CTRL, &phy_tmp);
1917 		phy_tmp |= CR_1000T_MS_ENABLE;
1918 		em_write_phy_reg(&adapter->hw, PHY_1000T_CTRL, phy_tmp);
1919 		if (adapter->hw.autoneg &&
1920 		    !em_phy_setup_autoneg(&adapter->hw) &&
1921 		    !em_read_phy_reg(&adapter->hw, PHY_CTRL, &phy_tmp)) {
1922 			phy_tmp |= (MII_CR_AUTO_NEG_EN |
1923 				    MII_CR_RESTART_AUTO_NEG);
1924 			em_write_phy_reg(&adapter->hw, PHY_CTRL, phy_tmp);
1925 		}
1926 	}
1927 	/* Restart process after EM_SMARTSPEED_MAX iterations */
1928 	if (adapter->smartspeed++ == EM_SMARTSPEED_MAX)
1929 		adapter->smartspeed = 0;
1930 }
1931 
1932 /*
1933  * Manage DMA'able memory.
1934  */
1935 static void
1936 em_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error)
1937 {
1938 	if (error)
1939 		return;
1940 	*(bus_addr_t*) arg = segs->ds_addr;
1941 }
1942 
1943 static int
1944 em_dma_malloc(struct adapter *adapter, bus_size_t size,
1945 	      struct em_dma_alloc *dma, int mapflags)
1946 {
1947 	int r;
1948 	device_t dev = adapter->dev;
1949 
1950 	r = bus_dma_tag_create(NULL,                    /* parent */
1951 			       PAGE_SIZE, 0,            /* alignment, bounds */
1952 			       BUS_SPACE_MAXADDR,       /* lowaddr */
1953 			       BUS_SPACE_MAXADDR,       /* highaddr */
1954 			       NULL, NULL,              /* filter, filterarg */
1955 			       size,                    /* maxsize */
1956 			       1,                       /* nsegments */
1957 			       size,                    /* maxsegsize */
1958 			       BUS_DMA_ALLOCNOW,        /* flags */
1959 			       &dma->dma_tag);
1960 	if (r != 0) {
1961 		device_printf(dev, "em_dma_malloc: bus_dma_tag_create failed; "
1962 			      "error %u\n", r);
1963 		goto fail_0;
1964 	}
1965 
1966 	r = bus_dmamem_alloc(dma->dma_tag, (void**) &dma->dma_vaddr,
1967 			     BUS_DMA_NOWAIT, &dma->dma_map);
1968 	if (r != 0) {
1969 		device_printf(dev, "em_dma_malloc: bus_dmammem_alloc failed; "
1970 			      "size %llu, error %d\n", (uintmax_t)size, r);
1971 		goto fail_2;
1972 	}
1973 
1974 	r = bus_dmamap_load(dma->dma_tag, dma->dma_map, dma->dma_vaddr,
1975 			    size,
1976 			    em_dmamap_cb,
1977 			    &dma->dma_paddr,
1978 			    mapflags | BUS_DMA_NOWAIT);
1979 	if (r != 0) {
1980 		device_printf(dev, "em_dma_malloc: bus_dmamap_load failed; "
1981 			      "error %u\n", r);
1982 		goto fail_3;
1983 	}
1984 
1985 	dma->dma_size = size;
1986 	return(0);
1987 
1988 fail_3:
1989 	bus_dmamap_unload(dma->dma_tag, dma->dma_map);
1990 fail_2:
1991 	bus_dmamem_free(dma->dma_tag, dma->dma_vaddr, dma->dma_map);
1992 	bus_dma_tag_destroy(dma->dma_tag);
1993 fail_0:
1994 	dma->dma_map = NULL;
1995 	dma->dma_tag = NULL;
1996 	return(r);
1997 }
1998 
1999 static void
2000 em_dma_free(struct adapter *adapter, struct em_dma_alloc *dma)
2001 {
2002 	bus_dmamap_unload(dma->dma_tag, dma->dma_map);
2003 	bus_dmamem_free(dma->dma_tag, dma->dma_vaddr, dma->dma_map);
2004 	bus_dma_tag_destroy(dma->dma_tag);
2005 }
2006 
2007 /*********************************************************************
2008  *
2009  *  Allocate memory for tx_buffer structures. The tx_buffer stores all
2010  *  the information needed to transmit a packet on the wire.
2011  *
2012  **********************************************************************/
2013 static int
2014 em_allocate_transmit_structures(struct adapter * adapter)
2015 {
2016 	adapter->tx_buffer_area = malloc(sizeof(struct em_buffer) *
2017 	    adapter->num_tx_desc, M_DEVBUF, M_NOWAIT | M_ZERO);
2018 	if (adapter->tx_buffer_area == NULL) {
2019 		device_printf(adapter->dev, "Unable to allocate tx_buffer memory\n");
2020 		return(ENOMEM);
2021 	}
2022 
2023 	return(0);
2024 }
2025 
2026 /*********************************************************************
2027  *
2028  *  Allocate and initialize transmit structures.
2029  *
2030  **********************************************************************/
2031 static int
2032 em_setup_transmit_structures(struct adapter * adapter)
2033 {
2034 	/*
2035 	 * Setup DMA descriptor areas.
2036 	 */
2037 	if (bus_dma_tag_create(NULL,                    /* parent */
2038 			       1, 0,			/* alignment, bounds */
2039 			       BUS_SPACE_MAXADDR,       /* lowaddr */
2040 			       BUS_SPACE_MAXADDR,       /* highaddr */
2041 			       NULL, NULL,              /* filter, filterarg */
2042 			       MCLBYTES * 8,            /* maxsize */
2043 			       EM_MAX_SCATTER,          /* nsegments */
2044 			       MCLBYTES * 8,            /* maxsegsize */
2045 			       BUS_DMA_ALLOCNOW,        /* flags */
2046 			       &adapter->txtag)) {
2047 		device_printf(adapter->dev, "Unable to allocate TX DMA tag\n");
2048 		return(ENOMEM);
2049 	}
2050 
2051 	if (em_allocate_transmit_structures(adapter))
2052 		return(ENOMEM);
2053 
2054         bzero((void *) adapter->tx_desc_base,
2055               (sizeof(struct em_tx_desc)) * adapter->num_tx_desc);
2056 
2057         adapter->next_avail_tx_desc = 0;
2058 	adapter->oldest_used_tx_desc = 0;
2059 
2060 	/* Set number of descriptors available */
2061 	adapter->num_tx_desc_avail = adapter->num_tx_desc;
2062 
2063 	/* Set checksum context */
2064 	adapter->active_checksum_context = OFFLOAD_NONE;
2065 
2066 	return(0);
2067 }
2068 
2069 /*********************************************************************
2070  *
2071  *  Enable transmit unit.
2072  *
2073  **********************************************************************/
2074 static void
2075 em_initialize_transmit_unit(struct adapter * adapter)
2076 {
2077 	uint32_t reg_tctl;
2078 	uint32_t reg_tipg = 0;
2079 	uint64_t bus_addr;
2080 
2081 	INIT_DEBUGOUT("em_initialize_transmit_unit: begin");
2082 
2083 	/* Setup the Base and Length of the Tx Descriptor Ring */
2084 	bus_addr = adapter->txdma.dma_paddr;
2085 	E1000_WRITE_REG(&adapter->hw, TDBAL, (uint32_t)bus_addr);
2086 	E1000_WRITE_REG(&adapter->hw, TDBAH, (uint32_t)(bus_addr >> 32));
2087 	E1000_WRITE_REG(&adapter->hw, TDLEN,
2088 			adapter->num_tx_desc * sizeof(struct em_tx_desc));
2089 
2090 	/* Setup the HW Tx Head and Tail descriptor pointers */
2091 	E1000_WRITE_REG(&adapter->hw, TDH, 0);
2092 	E1000_WRITE_REG(&adapter->hw, TDT, 0);
2093 
2094 	HW_DEBUGOUT2("Base = %x, Length = %x\n",
2095 		     E1000_READ_REG(&adapter->hw, TDBAL),
2096 		     E1000_READ_REG(&adapter->hw, TDLEN));
2097 
2098 	/* Set the default values for the Tx Inter Packet Gap timer */
2099 	switch (adapter->hw.mac_type) {
2100 	case em_82542_rev2_0:
2101 	case em_82542_rev2_1:
2102 		reg_tipg = DEFAULT_82542_TIPG_IPGT;
2103 		reg_tipg |= DEFAULT_82542_TIPG_IPGR1 << E1000_TIPG_IPGR1_SHIFT;
2104 		reg_tipg |= DEFAULT_82542_TIPG_IPGR2 << E1000_TIPG_IPGR2_SHIFT;
2105 		break;
2106 	default:
2107 		if (adapter->hw.media_type == em_media_type_fiber)
2108 			reg_tipg = DEFAULT_82543_TIPG_IPGT_FIBER;
2109 		else
2110 			reg_tipg = DEFAULT_82543_TIPG_IPGT_COPPER;
2111 		reg_tipg |= DEFAULT_82543_TIPG_IPGR1 << E1000_TIPG_IPGR1_SHIFT;
2112 		reg_tipg |= DEFAULT_82543_TIPG_IPGR2 << E1000_TIPG_IPGR2_SHIFT;
2113 	}
2114 
2115 	E1000_WRITE_REG(&adapter->hw, TIPG, reg_tipg);
2116 	E1000_WRITE_REG(&adapter->hw, TIDV, adapter->tx_int_delay.value);
2117 	if (adapter->hw.mac_type >= em_82540)
2118 		E1000_WRITE_REG(&adapter->hw, TADV,
2119 				adapter->tx_abs_int_delay.value);
2120 
2121 	/* Program the Transmit Control Register */
2122 	reg_tctl = E1000_TCTL_PSP | E1000_TCTL_EN |
2123 		   (E1000_COLLISION_THRESHOLD << E1000_CT_SHIFT);
2124 	if (adapter->hw.mac_type >= em_82571)
2125 		reg_tctl |= E1000_TCTL_MULR;
2126 	if (adapter->link_duplex == 1)
2127 		reg_tctl |= E1000_FDX_COLLISION_DISTANCE << E1000_COLD_SHIFT;
2128 	else
2129 		reg_tctl |= E1000_HDX_COLLISION_DISTANCE << E1000_COLD_SHIFT;
2130 	E1000_WRITE_REG(&adapter->hw, TCTL, reg_tctl);
2131 
2132 	/* Setup Transmit Descriptor Settings for this adapter */
2133 	adapter->txd_cmd = E1000_TXD_CMD_IFCS | E1000_TXD_CMD_RS;
2134 
2135 	if (adapter->tx_int_delay.value > 0)
2136 		adapter->txd_cmd |= E1000_TXD_CMD_IDE;
2137 }
2138 
2139 /*********************************************************************
2140  *
2141  *  Free all transmit related data structures.
2142  *
2143  **********************************************************************/
2144 static void
2145 em_free_transmit_structures(struct adapter * adapter)
2146 {
2147 	struct em_buffer *tx_buffer;
2148 	int i;
2149 
2150 	INIT_DEBUGOUT("free_transmit_structures: begin");
2151 
2152 	if (adapter->tx_buffer_area != NULL) {
2153 		tx_buffer = adapter->tx_buffer_area;
2154 		for (i = 0; i < adapter->num_tx_desc; i++, tx_buffer++) {
2155 			if (tx_buffer->m_head != NULL) {
2156 				bus_dmamap_unload(adapter->txtag, tx_buffer->map);
2157 				bus_dmamap_destroy(adapter->txtag, tx_buffer->map);
2158 				m_freem(tx_buffer->m_head);
2159 			}
2160 			tx_buffer->m_head = NULL;
2161 		}
2162 	}
2163 	if (adapter->tx_buffer_area != NULL) {
2164 		free(adapter->tx_buffer_area, M_DEVBUF);
2165 		adapter->tx_buffer_area = NULL;
2166 	}
2167 	if (adapter->txtag != NULL) {
2168 		bus_dma_tag_destroy(adapter->txtag);
2169 		adapter->txtag = NULL;
2170 	}
2171 }
2172 
2173 /*********************************************************************
2174  *
2175  *  The offload context needs to be set when we transfer the first
2176  *  packet of a particular protocol (TCP/UDP). We change the
2177  *  context only if the protocol type changes.
2178  *
2179  **********************************************************************/
2180 static void
2181 em_transmit_checksum_setup(struct adapter * adapter,
2182 			   struct mbuf *mp,
2183 			   uint32_t *txd_upper,
2184 			   uint32_t *txd_lower)
2185 {
2186 	struct em_context_desc *TXD;
2187 	struct em_buffer *tx_buffer;
2188 	int curr_txd;
2189 
2190 	if (mp->m_pkthdr.csum_flags) {
2191 		if (mp->m_pkthdr.csum_flags & CSUM_TCP) {
2192 			*txd_upper = E1000_TXD_POPTS_TXSM << 8;
2193 			*txd_lower = E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D;
2194 			if (adapter->active_checksum_context == OFFLOAD_TCP_IP)
2195 				return;
2196 			else
2197 				adapter->active_checksum_context = OFFLOAD_TCP_IP;
2198 		} else if (mp->m_pkthdr.csum_flags & CSUM_UDP) {
2199 			*txd_upper = E1000_TXD_POPTS_TXSM << 8;
2200 			*txd_lower = E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D;
2201 			if (adapter->active_checksum_context == OFFLOAD_UDP_IP)
2202 				return;
2203 			else
2204 				adapter->active_checksum_context = OFFLOAD_UDP_IP;
2205 		} else {
2206 			*txd_upper = 0;
2207 			*txd_lower = 0;
2208 			return;
2209 		}
2210 	} else {
2211 		*txd_upper = 0;
2212 		*txd_lower = 0;
2213 		return;
2214 	}
2215 
2216 	/* If we reach this point, the checksum offload context
2217 	 * needs to be reset.
2218 	 */
2219 	curr_txd = adapter->next_avail_tx_desc;
2220 	tx_buffer = &adapter->tx_buffer_area[curr_txd];
2221 	TXD = (struct em_context_desc *) &adapter->tx_desc_base[curr_txd];
2222 
2223 	TXD->lower_setup.ip_fields.ipcss = ETHER_HDR_LEN;
2224 	TXD->lower_setup.ip_fields.ipcso =
2225 	    ETHER_HDR_LEN + offsetof(struct ip, ip_sum);
2226 	TXD->lower_setup.ip_fields.ipcse =
2227 	    htole16(ETHER_HDR_LEN + sizeof(struct ip) - 1);
2228 
2229 	TXD->upper_setup.tcp_fields.tucss =
2230 	    ETHER_HDR_LEN + sizeof(struct ip);
2231 	TXD->upper_setup.tcp_fields.tucse = htole16(0);
2232 
2233 	if (adapter->active_checksum_context == OFFLOAD_TCP_IP) {
2234 		TXD->upper_setup.tcp_fields.tucso =
2235 		    ETHER_HDR_LEN + sizeof(struct ip) +
2236 		    offsetof(struct tcphdr, th_sum);
2237 	} else if (adapter->active_checksum_context == OFFLOAD_UDP_IP) {
2238 		TXD->upper_setup.tcp_fields.tucso =
2239 			ETHER_HDR_LEN + sizeof(struct ip) +
2240 			offsetof(struct udphdr, uh_sum);
2241 	}
2242 
2243 	TXD->tcp_seg_setup.data = htole32(0);
2244 	TXD->cmd_and_length = htole32(adapter->txd_cmd | E1000_TXD_CMD_DEXT);
2245 
2246 	tx_buffer->m_head = NULL;
2247 
2248 	if (++curr_txd == adapter->num_tx_desc)
2249 		curr_txd = 0;
2250 
2251 	adapter->num_tx_desc_avail--;
2252 	adapter->next_avail_tx_desc = curr_txd;
2253 }
2254 
2255 /**********************************************************************
2256  *
2257  *  Examine each tx_buffer in the used queue. If the hardware is done
2258  *  processing the packet then free associated resources. The
2259  *  tx_buffer is put back on the free queue.
2260  *
2261  **********************************************************************/
2262 
2263 static void
2264 em_clean_transmit_interrupts(struct adapter *adapter)
2265 {
2266 	int i, num_avail;
2267 	struct em_buffer *tx_buffer;
2268 	struct em_tx_desc *tx_desc;
2269 	struct ifnet *ifp = &adapter->interface_data.ac_if;
2270 
2271 	if (adapter->num_tx_desc_avail == adapter->num_tx_desc)
2272 		return;
2273 
2274 	num_avail = adapter->num_tx_desc_avail;
2275 	i = adapter->oldest_used_tx_desc;
2276 
2277 	tx_buffer = &adapter->tx_buffer_area[i];
2278 	tx_desc = &adapter->tx_desc_base[i];
2279 
2280 	bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
2281 			BUS_DMASYNC_POSTREAD);
2282 
2283 	while(tx_desc->upper.fields.status & E1000_TXD_STAT_DD) {
2284 		tx_desc->upper.data = 0;
2285 		num_avail++;
2286 
2287 		logif(pkt_txclean);
2288 
2289 		if (tx_buffer->m_head) {
2290 			ifp->if_opackets++;
2291 			bus_dmamap_sync(adapter->txtag, tx_buffer->map,
2292 					BUS_DMASYNC_POSTWRITE);
2293 			bus_dmamap_unload(adapter->txtag, tx_buffer->map);
2294 			bus_dmamap_destroy(adapter->txtag, tx_buffer->map);
2295 
2296 			m_freem(tx_buffer->m_head);
2297 			tx_buffer->m_head = NULL;
2298 		}
2299 
2300 		if (++i == adapter->num_tx_desc)
2301 			i = 0;
2302 
2303 		tx_buffer = &adapter->tx_buffer_area[i];
2304 		tx_desc = &adapter->tx_desc_base[i];
2305 	}
2306 
2307 	bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
2308 			BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
2309 
2310 	adapter->oldest_used_tx_desc = i;
2311 
2312 	/*
2313 	 * If we have enough room, clear IFF_OACTIVE to tell the stack
2314 	 * that it is OK to send packets.
2315 	 * If there are no pending descriptors, clear the timeout. Otherwise,
2316 	 * if some descriptors have been freed, restart the timeout.
2317 	 */
2318 	if (num_avail > EM_TX_CLEANUP_THRESHOLD) {
2319 		ifp->if_flags &= ~IFF_OACTIVE;
2320 		if (num_avail == adapter->num_tx_desc)
2321 			ifp->if_timer = 0;
2322 		else if (num_avail == adapter->num_tx_desc_avail)
2323 			ifp->if_timer = EM_TX_TIMEOUT;
2324 	}
2325 	adapter->num_tx_desc_avail = num_avail;
2326 }
2327 
2328 /*********************************************************************
2329  *
2330  *  Get a buffer from system mbuf buffer pool.
2331  *
2332  **********************************************************************/
2333 static int
2334 em_get_buf(int i, struct adapter *adapter, struct mbuf *nmp, int how)
2335 {
2336 	struct mbuf *mp = nmp;
2337 	struct em_buffer *rx_buffer;
2338 	struct ifnet *ifp;
2339 	bus_addr_t paddr;
2340 	int error;
2341 
2342 	ifp = &adapter->interface_data.ac_if;
2343 
2344 	if (mp == NULL) {
2345 		mp = m_getcl(how, MT_DATA, M_PKTHDR);
2346 		if (mp == NULL) {
2347 			adapter->mbuf_cluster_failed++;
2348 			return(ENOBUFS);
2349 		}
2350 		mp->m_len = mp->m_pkthdr.len = MCLBYTES;
2351 	} else {
2352 		mp->m_len = mp->m_pkthdr.len = MCLBYTES;
2353 		mp->m_data = mp->m_ext.ext_buf;
2354 		mp->m_next = NULL;
2355 	}
2356 	if (ifp->if_mtu <= ETHERMTU)
2357 		m_adj(mp, ETHER_ALIGN);
2358 
2359 	rx_buffer = &adapter->rx_buffer_area[i];
2360 
2361 	/*
2362 	 * Using memory from the mbuf cluster pool, invoke the
2363 	 * bus_dma machinery to arrange the memory mapping.
2364 	 */
2365 	error = bus_dmamap_load(adapter->rxtag, rx_buffer->map,
2366 				mtod(mp, void *), mp->m_len,
2367 				em_dmamap_cb, &paddr, 0);
2368 	if (error) {
2369 		m_free(mp);
2370 		return(error);
2371 	}
2372 	rx_buffer->m_head = mp;
2373 	adapter->rx_desc_base[i].buffer_addr = htole64(paddr);
2374 	bus_dmamap_sync(adapter->rxtag, rx_buffer->map, BUS_DMASYNC_PREREAD);
2375 
2376 	return(0);
2377 }
2378 
2379 /*********************************************************************
2380  *
2381  *  Allocate memory for rx_buffer structures. Since we use one
2382  *  rx_buffer per received packet, the maximum number of rx_buffer's
2383  *  that we'll need is equal to the number of receive descriptors
2384  *  that we've allocated.
2385  *
2386  **********************************************************************/
2387 static int
2388 em_allocate_receive_structures(struct adapter *adapter)
2389 {
2390 	int i, error, size;
2391 	struct em_buffer *rx_buffer;
2392 
2393 	size = adapter->num_rx_desc * sizeof(struct em_buffer);
2394 	adapter->rx_buffer_area = malloc(size, M_DEVBUF, M_WAITOK | M_ZERO);
2395 
2396 	error = bus_dma_tag_create(NULL,		/* parent */
2397 				   1, 0,		/* alignment, bounds */
2398 				   BUS_SPACE_MAXADDR,	/* lowaddr */
2399 				   BUS_SPACE_MAXADDR,	/* highaddr */
2400 				   NULL, NULL,		/* filter, filterarg */
2401 				   MCLBYTES,		/* maxsize */
2402 				   1,			/* nsegments */
2403 				   MCLBYTES,		/* maxsegsize */
2404 				   BUS_DMA_ALLOCNOW,	/* flags */
2405 				   &adapter->rxtag);
2406 	if (error != 0) {
2407 		device_printf(adapter->dev, "em_allocate_receive_structures: "
2408 			      "bus_dma_tag_create failed; error %u\n", error);
2409 		goto fail_0;
2410 	}
2411 
2412 	rx_buffer = adapter->rx_buffer_area;
2413 	for (i = 0; i < adapter->num_rx_desc; i++, rx_buffer++) {
2414 		error = bus_dmamap_create(adapter->rxtag, BUS_DMA_NOWAIT,
2415 					  &rx_buffer->map);
2416 		if (error != 0) {
2417 			device_printf(adapter->dev,
2418 				      "em_allocate_receive_structures: "
2419 				      "bus_dmamap_create failed; error %u\n",
2420 				      error);
2421 			goto fail_1;
2422 		}
2423 	}
2424 
2425 	for (i = 0; i < adapter->num_rx_desc; i++) {
2426 		error = em_get_buf(i, adapter, NULL, MB_WAIT);
2427 		if (error != 0) {
2428 			adapter->rx_buffer_area[i].m_head = NULL;
2429 			adapter->rx_desc_base[i].buffer_addr = 0;
2430 			return(error);
2431 		}
2432 	}
2433 
2434 	bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
2435 			BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
2436 
2437 	return(0);
2438 
2439 fail_1:
2440 	bus_dma_tag_destroy(adapter->rxtag);
2441 fail_0:
2442 	adapter->rxtag = NULL;
2443 	free(adapter->rx_buffer_area, M_DEVBUF);
2444 	adapter->rx_buffer_area = NULL;
2445 	return(error);
2446 }
2447 
2448 /*********************************************************************
2449  *
2450  *  Allocate and initialize receive structures.
2451  *
2452  **********************************************************************/
2453 static int
2454 em_setup_receive_structures(struct adapter *adapter)
2455 {
2456 	bzero((void *) adapter->rx_desc_base,
2457 	      (sizeof(struct em_rx_desc)) * adapter->num_rx_desc);
2458 
2459 	if (em_allocate_receive_structures(adapter))
2460 		return(ENOMEM);
2461 
2462 	/* Setup our descriptor pointers */
2463 	adapter->next_rx_desc_to_check = 0;
2464 	return(0);
2465 }
2466 
2467 /*********************************************************************
2468  *
2469  *  Enable receive unit.
2470  *
2471  **********************************************************************/
2472 static void
2473 em_initialize_receive_unit(struct adapter *adapter)
2474 {
2475 	uint32_t reg_rctl;
2476 	uint32_t reg_rxcsum;
2477 	struct ifnet *ifp;
2478 	uint64_t bus_addr;
2479 
2480 	INIT_DEBUGOUT("em_initialize_receive_unit: begin");
2481 
2482 	ifp = &adapter->interface_data.ac_if;
2483 
2484 	/* Make sure receives are disabled while setting up the descriptor ring */
2485 	E1000_WRITE_REG(&adapter->hw, RCTL, 0);
2486 
2487 	/* Set the Receive Delay Timer Register */
2488 	E1000_WRITE_REG(&adapter->hw, RDTR,
2489 			adapter->rx_int_delay.value | E1000_RDT_FPDB);
2490 
2491 	if(adapter->hw.mac_type >= em_82540) {
2492 		E1000_WRITE_REG(&adapter->hw, RADV,
2493 				adapter->rx_abs_int_delay.value);
2494 
2495 		/* Set the interrupt throttling rate in 256ns increments */
2496 		if (em_int_throttle_ceil) {
2497 			E1000_WRITE_REG(&adapter->hw, ITR,
2498 				1000000000 / 256 / em_int_throttle_ceil);
2499 		} else {
2500 			E1000_WRITE_REG(&adapter->hw, ITR, 0);
2501 		}
2502 	}
2503 
2504 	/* Setup the Base and Length of the Rx Descriptor Ring */
2505 	bus_addr = adapter->rxdma.dma_paddr;
2506 	E1000_WRITE_REG(&adapter->hw, RDBAL, (uint32_t)bus_addr);
2507 	E1000_WRITE_REG(&adapter->hw, RDBAH, (uint32_t)(bus_addr >> 32));
2508 	E1000_WRITE_REG(&adapter->hw, RDLEN, adapter->num_rx_desc *
2509 			sizeof(struct em_rx_desc));
2510 
2511 	/* Setup the HW Rx Head and Tail Descriptor Pointers */
2512 	E1000_WRITE_REG(&adapter->hw, RDH, 0);
2513 	E1000_WRITE_REG(&adapter->hw, RDT, adapter->num_rx_desc - 1);
2514 
2515 	/* Setup the Receive Control Register */
2516 	reg_rctl = E1000_RCTL_EN | E1000_RCTL_BAM | E1000_RCTL_LBM_NO |
2517 		   E1000_RCTL_RDMTS_HALF |
2518 		   (adapter->hw.mc_filter_type << E1000_RCTL_MO_SHIFT);
2519 
2520 	if (adapter->hw.tbi_compatibility_on == TRUE)
2521 		reg_rctl |= E1000_RCTL_SBP;
2522 
2523 	switch (adapter->rx_buffer_len) {
2524 	default:
2525 	case EM_RXBUFFER_2048:
2526 		reg_rctl |= E1000_RCTL_SZ_2048;
2527 		break;
2528 	case EM_RXBUFFER_4096:
2529 		reg_rctl |= E1000_RCTL_SZ_4096 | E1000_RCTL_BSEX | E1000_RCTL_LPE;
2530 		break;
2531 	case EM_RXBUFFER_8192:
2532 		reg_rctl |= E1000_RCTL_SZ_8192 | E1000_RCTL_BSEX | E1000_RCTL_LPE;
2533 		break;
2534 	case EM_RXBUFFER_16384:
2535 		reg_rctl |= E1000_RCTL_SZ_16384 | E1000_RCTL_BSEX | E1000_RCTL_LPE;
2536 		break;
2537 	}
2538 
2539 	if (ifp->if_mtu > ETHERMTU)
2540 		reg_rctl |= E1000_RCTL_LPE;
2541 
2542 	/* Enable 82543 Receive Checksum Offload for TCP and UDP */
2543 	if ((adapter->hw.mac_type >= em_82543) &&
2544 	    (ifp->if_capenable & IFCAP_RXCSUM)) {
2545 		reg_rxcsum = E1000_READ_REG(&adapter->hw, RXCSUM);
2546 		reg_rxcsum |= (E1000_RXCSUM_IPOFL | E1000_RXCSUM_TUOFL);
2547 		E1000_WRITE_REG(&adapter->hw, RXCSUM, reg_rxcsum);
2548 	}
2549 
2550 	/* Enable Receives */
2551 	E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
2552 }
2553 
2554 /*********************************************************************
2555  *
2556  *  Free receive related data structures.
2557  *
2558  **********************************************************************/
2559 static void
2560 em_free_receive_structures(struct adapter *adapter)
2561 {
2562 	struct em_buffer *rx_buffer;
2563 	int i;
2564 
2565 	INIT_DEBUGOUT("free_receive_structures: begin");
2566 
2567 	if (adapter->rx_buffer_area != NULL) {
2568 		rx_buffer = adapter->rx_buffer_area;
2569 		for (i = 0; i < adapter->num_rx_desc; i++, rx_buffer++) {
2570 			if (rx_buffer->map != NULL) {
2571 				bus_dmamap_unload(adapter->rxtag, rx_buffer->map);
2572 				bus_dmamap_destroy(adapter->rxtag, rx_buffer->map);
2573 			}
2574 			if (rx_buffer->m_head != NULL)
2575 				m_freem(rx_buffer->m_head);
2576 			rx_buffer->m_head = NULL;
2577 		}
2578 	}
2579 	if (adapter->rx_buffer_area != NULL) {
2580 		free(adapter->rx_buffer_area, M_DEVBUF);
2581 		adapter->rx_buffer_area = NULL;
2582 	}
2583 	if (adapter->rxtag != NULL) {
2584 		bus_dma_tag_destroy(adapter->rxtag);
2585 		adapter->rxtag = NULL;
2586 	}
2587 }
2588 
2589 /*********************************************************************
2590  *
2591  *  This routine executes in interrupt context. It replenishes
2592  *  the mbufs in the descriptor and sends data which has been
2593  *  dma'ed into host memory to upper layer.
2594  *
2595  *  We loop at most count times if count is > 0, or until done if
2596  *  count < 0.
2597  *
2598  *********************************************************************/
2599 static void
2600 em_process_receive_interrupts(struct adapter *adapter, int count)
2601 {
2602 	struct ifnet *ifp;
2603 	struct mbuf *mp;
2604 	uint8_t accept_frame = 0;
2605 	uint8_t eop = 0;
2606 	uint16_t len, desc_len, prev_len_adj;
2607 	int i;
2608 
2609 	/* Pointer to the receive descriptor being examined. */
2610 	struct em_rx_desc *current_desc;
2611 
2612 	ifp = &adapter->interface_data.ac_if;
2613 	i = adapter->next_rx_desc_to_check;
2614 	current_desc = &adapter->rx_desc_base[i];
2615 
2616 	bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
2617 			BUS_DMASYNC_POSTREAD);
2618 
2619 	if (!((current_desc->status) & E1000_RXD_STAT_DD))
2620 		return;
2621 
2622 	while ((current_desc->status & E1000_RXD_STAT_DD) && (count != 0)) {
2623 		logif(pkt_receive);
2624 		mp = adapter->rx_buffer_area[i].m_head;
2625 		bus_dmamap_sync(adapter->rxtag, adapter->rx_buffer_area[i].map,
2626 				BUS_DMASYNC_POSTREAD);
2627 
2628 		accept_frame = 1;
2629 		prev_len_adj = 0;
2630 		desc_len = le16toh(current_desc->length);
2631 		if (current_desc->status & E1000_RXD_STAT_EOP) {
2632 			count--;
2633 			eop = 1;
2634 			if (desc_len < ETHER_CRC_LEN) {
2635 				len = 0;
2636 				prev_len_adj = ETHER_CRC_LEN - desc_len;
2637 			} else {
2638 				len = desc_len - ETHER_CRC_LEN;
2639 			}
2640 		} else {
2641 			eop = 0;
2642 			len = desc_len;
2643 		}
2644 
2645 		if (current_desc->errors & E1000_RXD_ERR_FRAME_ERR_MASK) {
2646 			uint8_t last_byte;
2647 			uint32_t pkt_len = desc_len;
2648 
2649 			if (adapter->fmp != NULL)
2650 				pkt_len += adapter->fmp->m_pkthdr.len;
2651 
2652 			last_byte = *(mtod(mp, caddr_t) + desc_len - 1);
2653 
2654 			if (TBI_ACCEPT(&adapter->hw, current_desc->status,
2655 				       current_desc->errors,
2656 				       pkt_len, last_byte)) {
2657 				em_tbi_adjust_stats(&adapter->hw,
2658 						    &adapter->stats,
2659 						    pkt_len,
2660 						    adapter->hw.mac_addr);
2661 				if (len > 0)
2662 					len--;
2663 			} else {
2664 				accept_frame = 0;
2665 			}
2666 		}
2667 
2668 		if (accept_frame) {
2669 			if (em_get_buf(i, adapter, NULL, MB_DONTWAIT) == ENOBUFS) {
2670 				adapter->dropped_pkts++;
2671 				em_get_buf(i, adapter, mp, MB_DONTWAIT);
2672 				if (adapter->fmp != NULL)
2673 					m_freem(adapter->fmp);
2674 				adapter->fmp = NULL;
2675 				adapter->lmp = NULL;
2676 				break;
2677 			}
2678 
2679 			/* Assign correct length to the current fragment */
2680 			mp->m_len = len;
2681 
2682 			if (adapter->fmp == NULL) {
2683 				mp->m_pkthdr.len = len;
2684 				adapter->fmp = mp;	 /* Store the first mbuf */
2685 				adapter->lmp = mp;
2686 			} else {
2687 				/* Chain mbuf's together */
2688 				/*
2689 				 * Adjust length of previous mbuf in chain if we
2690 				 * received less than 4 bytes in the last descriptor.
2691 				 */
2692 				if (prev_len_adj > 0) {
2693 					adapter->lmp->m_len -= prev_len_adj;
2694 					adapter->fmp->m_pkthdr.len -= prev_len_adj;
2695 				}
2696 				adapter->lmp->m_next = mp;
2697 				adapter->lmp = adapter->lmp->m_next;
2698 				adapter->fmp->m_pkthdr.len += len;
2699 			}
2700 
2701 			if (eop) {
2702 				adapter->fmp->m_pkthdr.rcvif = ifp;
2703 				ifp->if_ipackets++;
2704 
2705 				em_receive_checksum(adapter, current_desc,
2706 						    adapter->fmp);
2707 				if (current_desc->status & E1000_RXD_STAT_VP) {
2708 					VLAN_INPUT_TAG(adapter->fmp,
2709 						       (current_desc->special &
2710 							E1000_RXD_SPC_VLAN_MASK));
2711 				} else {
2712 					ifp->if_input(ifp, adapter->fmp);
2713 				}
2714 				adapter->fmp = NULL;
2715 				adapter->lmp = NULL;
2716 			}
2717 		} else {
2718 			adapter->dropped_pkts++;
2719 			em_get_buf(i, adapter, mp, MB_DONTWAIT);
2720 			if (adapter->fmp != NULL)
2721 				m_freem(adapter->fmp);
2722 			adapter->fmp = NULL;
2723 			adapter->lmp = NULL;
2724 		}
2725 
2726 		/* Zero out the receive descriptors status  */
2727 		current_desc->status = 0;
2728 
2729 		/* Advance the E1000's Receive Queue #0  "Tail Pointer". */
2730 		E1000_WRITE_REG(&adapter->hw, RDT, i);
2731 
2732 		/* Advance our pointers to the next descriptor */
2733 		if (++i == adapter->num_rx_desc) {
2734 			i = 0;
2735 			current_desc = adapter->rx_desc_base;
2736 		} else {
2737 			current_desc++;
2738 		}
2739 	}
2740 
2741 	bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
2742 			BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
2743 
2744 	adapter->next_rx_desc_to_check = i;
2745 }
2746 
2747 /*********************************************************************
2748  *
2749  *  Verify that the hardware indicated that the checksum is valid.
2750  *  Inform the stack about the status of checksum so that stack
2751  *  doesn't spend time verifying the checksum.
2752  *
2753  *********************************************************************/
2754 static void
2755 em_receive_checksum(struct adapter *adapter,
2756 		    struct em_rx_desc *rx_desc,
2757 		    struct mbuf *mp)
2758 {
2759 	/* 82543 or newer only */
2760 	if ((adapter->hw.mac_type < em_82543) ||
2761 	    /* Ignore Checksum bit is set */
2762 	    (rx_desc->status & E1000_RXD_STAT_IXSM)) {
2763 		mp->m_pkthdr.csum_flags = 0;
2764 		return;
2765 	}
2766 
2767 	if (rx_desc->status & E1000_RXD_STAT_IPCS) {
2768 		/* Did it pass? */
2769 		if (!(rx_desc->errors & E1000_RXD_ERR_IPE)) {
2770 			/* IP Checksum Good */
2771 			mp->m_pkthdr.csum_flags = CSUM_IP_CHECKED;
2772 			mp->m_pkthdr.csum_flags |= CSUM_IP_VALID;
2773 		} else {
2774 			mp->m_pkthdr.csum_flags = 0;
2775 		}
2776 	}
2777 
2778 	if (rx_desc->status & E1000_RXD_STAT_TCPCS) {
2779 		/* Did it pass? */
2780 		if (!(rx_desc->errors & E1000_RXD_ERR_TCPE)) {
2781 			mp->m_pkthdr.csum_flags |=
2782 			(CSUM_DATA_VALID | CSUM_PSEUDO_HDR);
2783 			mp->m_pkthdr.csum_data = htons(0xffff);
2784 		}
2785 	}
2786 }
2787 
2788 
2789 static void
2790 em_enable_vlans(struct adapter *adapter)
2791 {
2792 	uint32_t ctrl;
2793 
2794 	E1000_WRITE_REG(&adapter->hw, VET, ETHERTYPE_VLAN);
2795 
2796 	ctrl = E1000_READ_REG(&adapter->hw, CTRL);
2797 	ctrl |= E1000_CTRL_VME;
2798 	E1000_WRITE_REG(&adapter->hw, CTRL, ctrl);
2799 }
2800 
2801 /*
2802  * note: we must call bus_enable_intr() prior to enabling the hardware
2803  * interrupt and bus_disable_intr() after disabling the hardware interrupt
2804  * in order to avoid handler execution races from scheduled interrupt
2805  * threads.
2806  */
2807 static void
2808 em_enable_intr(struct adapter *adapter)
2809 {
2810 	struct ifnet *ifp = &adapter->interface_data.ac_if;
2811 
2812 	if ((ifp->if_flags & IFF_POLLING) == 0) {
2813 		lwkt_serialize_handler_enable(ifp->if_serializer);
2814 		E1000_WRITE_REG(&adapter->hw, IMS, (IMS_ENABLE_MASK));
2815 	}
2816 }
2817 
2818 static void
2819 em_disable_intr(struct adapter *adapter)
2820 {
2821 	/*
2822 	 * The first version of 82542 had an errata where when link was
2823 	 * forced it would stay up even up even if the cable was disconnected.
2824 	 * Sequence errors were used to detect the disconnect and then the
2825 	 * driver would unforce the link.  This code in the in the ISR.  For
2826 	 * this to work correctly the Sequence error interrupt had to be
2827 	 * enabled all the time.
2828 	 */
2829 	if (adapter->hw.mac_type == em_82542_rev2_0) {
2830 		E1000_WRITE_REG(&adapter->hw, IMC,
2831 				(0xffffffff & ~E1000_IMC_RXSEQ));
2832 	} else {
2833 		E1000_WRITE_REG(&adapter->hw, IMC, 0xffffffff);
2834 	}
2835 
2836 	lwkt_serialize_handler_disable(adapter->interface_data.ac_if.if_serializer);
2837 }
2838 
2839 static int
2840 em_is_valid_ether_addr(uint8_t *addr)
2841 {
2842 	char zero_addr[6] = { 0, 0, 0, 0, 0, 0 };
2843 
2844 	if ((addr[0] & 1) || (!bcmp(addr, zero_addr, ETHER_ADDR_LEN)))
2845 		return(FALSE);
2846 	else
2847 		return(TRUE);
2848 }
2849 
2850 void
2851 em_write_pci_cfg(struct em_hw *hw, uint32_t reg, uint16_t *value)
2852 {
2853 	pci_write_config(((struct em_osdep *)hw->back)->dev, reg, *value, 2);
2854 }
2855 
2856 void
2857 em_read_pci_cfg(struct em_hw *hw, uint32_t reg, uint16_t *value)
2858 {
2859 	*value = pci_read_config(((struct em_osdep *)hw->back)->dev, reg, 2);
2860 }
2861 
2862 void
2863 em_pci_set_mwi(struct em_hw *hw)
2864 {
2865 	pci_write_config(((struct em_osdep *)hw->back)->dev, PCIR_COMMAND,
2866 			 (hw->pci_cmd_word | CMD_MEM_WRT_INVALIDATE), 2);
2867 }
2868 
2869 void
2870 em_pci_clear_mwi(struct em_hw *hw)
2871 {
2872 	pci_write_config(((struct em_osdep *)hw->back)->dev, PCIR_COMMAND,
2873 			 (hw->pci_cmd_word & ~CMD_MEM_WRT_INVALIDATE), 2);
2874 }
2875 
2876 uint32_t
2877 em_read_reg_io(struct em_hw *hw, uint32_t offset)
2878 {
2879 	bus_space_write_4(hw->reg_io_tag, hw->reg_io_handle, 0, offset);
2880 	return(bus_space_read_4(hw->reg_io_tag, hw->reg_io_handle, 4));
2881 }
2882 
2883 void
2884 em_write_reg_io(struct em_hw *hw, uint32_t offset, uint32_t value)
2885 {
2886 	bus_space_write_4(hw->reg_io_tag, hw->reg_io_handle, 0, offset);
2887 	bus_space_write_4(hw->reg_io_tag, hw->reg_io_handle, 4, value);
2888 }
2889 
2890 /*********************************************************************
2891  * 82544 Coexistence issue workaround.
2892  *    There are 2 issues.
2893  *	1. Transmit Hang issue.
2894  *    To detect this issue, following equation can be used...
2895  *          SIZE[3:0] + ADDR[2:0] = SUM[3:0].
2896  *          If SUM[3:0] is in between 1 to 4, we will have this issue.
2897  *
2898  *	2. DAC issue.
2899  *    To detect this issue, following equation can be used...
2900  *          SIZE[3:0] + ADDR[2:0] = SUM[3:0].
2901  *          If SUM[3:0] is in between 9 to c, we will have this issue.
2902  *
2903  *
2904  *    WORKAROUND:
2905  *          Make sure we do not have ending address as 1,2,3,4(Hang) or
2906  *          9,a,b,c (DAC)
2907  *
2908 *************************************************************************/
2909 static uint32_t
2910 em_fill_descriptors(uint64_t address, uint32_t length, PDESC_ARRAY desc_array)
2911 {
2912 	/* Since issue is sensitive to length and address.*/
2913 	/* Let us first check the address...*/
2914 	uint32_t safe_terminator;
2915 	if (length <= 4) {
2916 		desc_array->descriptor[0].address = address;
2917 		desc_array->descriptor[0].length = length;
2918 		desc_array->elements = 1;
2919 		return(desc_array->elements);
2920 	}
2921 	safe_terminator = (uint32_t)((((uint32_t)address & 0x7) + (length & 0xF)) & 0xF);
2922 	/* if it does not fall between 0x1 to 0x4 and 0x9 to 0xC then return */
2923 	if (safe_terminator == 0 ||
2924 	    (safe_terminator > 4 && safe_terminator < 9) ||
2925 	    (safe_terminator > 0xC && safe_terminator <= 0xF)) {
2926 		desc_array->descriptor[0].address = address;
2927 		desc_array->descriptor[0].length = length;
2928 		desc_array->elements = 1;
2929 		return(desc_array->elements);
2930 	}
2931 
2932 	desc_array->descriptor[0].address = address;
2933 	desc_array->descriptor[0].length = length - 4;
2934 	desc_array->descriptor[1].address = address + (length - 4);
2935 	desc_array->descriptor[1].length = 4;
2936 	desc_array->elements = 2;
2937 	return(desc_array->elements);
2938 }
2939 
2940 /**********************************************************************
2941  *
2942  *  Update the board statistics counters.
2943  *
2944  **********************************************************************/
2945 static void
2946 em_update_stats_counters(struct adapter *adapter)
2947 {
2948 	struct ifnet   *ifp;
2949 
2950 	if (adapter->hw.media_type == em_media_type_copper ||
2951 	    (E1000_READ_REG(&adapter->hw, STATUS) & E1000_STATUS_LU)) {
2952 		adapter->stats.symerrs += E1000_READ_REG(&adapter->hw, SYMERRS);
2953 		adapter->stats.sec += E1000_READ_REG(&adapter->hw, SEC);
2954 	}
2955 	adapter->stats.crcerrs += E1000_READ_REG(&adapter->hw, CRCERRS);
2956 	adapter->stats.mpc += E1000_READ_REG(&adapter->hw, MPC);
2957 	adapter->stats.scc += E1000_READ_REG(&adapter->hw, SCC);
2958 	adapter->stats.ecol += E1000_READ_REG(&adapter->hw, ECOL);
2959 
2960 	adapter->stats.mcc += E1000_READ_REG(&adapter->hw, MCC);
2961 	adapter->stats.latecol += E1000_READ_REG(&adapter->hw, LATECOL);
2962 	adapter->stats.colc += E1000_READ_REG(&adapter->hw, COLC);
2963 	adapter->stats.dc += E1000_READ_REG(&adapter->hw, DC);
2964 	adapter->stats.rlec += E1000_READ_REG(&adapter->hw, RLEC);
2965 	adapter->stats.xonrxc += E1000_READ_REG(&adapter->hw, XONRXC);
2966 	adapter->stats.xontxc += E1000_READ_REG(&adapter->hw, XONTXC);
2967 	adapter->stats.xoffrxc += E1000_READ_REG(&adapter->hw, XOFFRXC);
2968 	adapter->stats.xofftxc += E1000_READ_REG(&adapter->hw, XOFFTXC);
2969 	adapter->stats.fcruc += E1000_READ_REG(&adapter->hw, FCRUC);
2970 	adapter->stats.prc64 += E1000_READ_REG(&adapter->hw, PRC64);
2971 	adapter->stats.prc127 += E1000_READ_REG(&adapter->hw, PRC127);
2972 	adapter->stats.prc255 += E1000_READ_REG(&adapter->hw, PRC255);
2973 	adapter->stats.prc511 += E1000_READ_REG(&adapter->hw, PRC511);
2974 	adapter->stats.prc1023 += E1000_READ_REG(&adapter->hw, PRC1023);
2975 	adapter->stats.prc1522 += E1000_READ_REG(&adapter->hw, PRC1522);
2976 	adapter->stats.gprc += E1000_READ_REG(&adapter->hw, GPRC);
2977 	adapter->stats.bprc += E1000_READ_REG(&adapter->hw, BPRC);
2978 	adapter->stats.mprc += E1000_READ_REG(&adapter->hw, MPRC);
2979 	adapter->stats.gptc += E1000_READ_REG(&adapter->hw, GPTC);
2980 
2981 	/* For the 64-bit byte counters the low dword must be read first. */
2982 	/* Both registers clear on the read of the high dword */
2983 
2984 	adapter->stats.gorcl += E1000_READ_REG(&adapter->hw, GORCL);
2985 	adapter->stats.gorch += E1000_READ_REG(&adapter->hw, GORCH);
2986 	adapter->stats.gotcl += E1000_READ_REG(&adapter->hw, GOTCL);
2987 	adapter->stats.gotch += E1000_READ_REG(&adapter->hw, GOTCH);
2988 
2989 	adapter->stats.rnbc += E1000_READ_REG(&adapter->hw, RNBC);
2990 	adapter->stats.ruc += E1000_READ_REG(&adapter->hw, RUC);
2991 	adapter->stats.rfc += E1000_READ_REG(&adapter->hw, RFC);
2992 	adapter->stats.roc += E1000_READ_REG(&adapter->hw, ROC);
2993 	adapter->stats.rjc += E1000_READ_REG(&adapter->hw, RJC);
2994 
2995 	adapter->stats.torl += E1000_READ_REG(&adapter->hw, TORL);
2996 	adapter->stats.torh += E1000_READ_REG(&adapter->hw, TORH);
2997 	adapter->stats.totl += E1000_READ_REG(&adapter->hw, TOTL);
2998 	adapter->stats.toth += E1000_READ_REG(&adapter->hw, TOTH);
2999 
3000 	adapter->stats.tpr += E1000_READ_REG(&adapter->hw, TPR);
3001 	adapter->stats.tpt += E1000_READ_REG(&adapter->hw, TPT);
3002 	adapter->stats.ptc64 += E1000_READ_REG(&adapter->hw, PTC64);
3003 	adapter->stats.ptc127 += E1000_READ_REG(&adapter->hw, PTC127);
3004 	adapter->stats.ptc255 += E1000_READ_REG(&adapter->hw, PTC255);
3005 	adapter->stats.ptc511 += E1000_READ_REG(&adapter->hw, PTC511);
3006 	adapter->stats.ptc1023 += E1000_READ_REG(&adapter->hw, PTC1023);
3007 	adapter->stats.ptc1522 += E1000_READ_REG(&adapter->hw, PTC1522);
3008 	adapter->stats.mptc += E1000_READ_REG(&adapter->hw, MPTC);
3009 	adapter->stats.bptc += E1000_READ_REG(&adapter->hw, BPTC);
3010 
3011 	if (adapter->hw.mac_type >= em_82543) {
3012 		adapter->stats.algnerrc +=
3013 		    E1000_READ_REG(&adapter->hw, ALGNERRC);
3014 		adapter->stats.rxerrc +=
3015 		    E1000_READ_REG(&adapter->hw, RXERRC);
3016 		adapter->stats.tncrs +=
3017 		    E1000_READ_REG(&adapter->hw, TNCRS);
3018 		adapter->stats.cexterr +=
3019 		    E1000_READ_REG(&adapter->hw, CEXTERR);
3020 		adapter->stats.tsctc +=
3021 		    E1000_READ_REG(&adapter->hw, TSCTC);
3022 		adapter->stats.tsctfc +=
3023 		    E1000_READ_REG(&adapter->hw, TSCTFC);
3024 	}
3025 	ifp = &adapter->interface_data.ac_if;
3026 
3027 	/* Fill out the OS statistics structure */
3028 	ifp->if_ibytes = adapter->stats.gorcl;
3029 	ifp->if_obytes = adapter->stats.gotcl;
3030 	ifp->if_imcasts = adapter->stats.mprc;
3031 	ifp->if_collisions = adapter->stats.colc;
3032 
3033 	/* Rx Errors */
3034 	ifp->if_ierrors = adapter->dropped_pkts + adapter->stats.rxerrc +
3035 	    adapter->stats.crcerrs + adapter->stats.algnerrc +
3036 	    adapter->stats.rlec + adapter->stats.mpc + adapter->stats.cexterr;
3037 
3038 	/* Tx Errors */
3039 	ifp->if_oerrors = adapter->stats.ecol + adapter->stats.latecol;
3040 }
3041 
3042 
3043 /**********************************************************************
3044  *
3045  *  This routine is called only when em_display_debug_stats is enabled.
3046  *  This routine provides a way to take a look at important statistics
3047  *  maintained by the driver and hardware.
3048  *
3049  **********************************************************************/
3050 static void
3051 em_print_debug_info(struct adapter *adapter)
3052 {
3053 	device_t dev= adapter->dev;
3054 	uint8_t *hw_addr = adapter->hw.hw_addr;
3055 
3056 	device_printf(dev, "Adapter hardware address = %p \n", hw_addr);
3057 	device_printf(dev, "CTRL  = 0x%x\n",
3058 		      E1000_READ_REG(&adapter->hw, CTRL));
3059 	device_printf(dev, "RCTL  = 0x%x PS=(0x8402)\n",
3060 		      E1000_READ_REG(&adapter->hw, RCTL));
3061 	device_printf(dev, "Packet buffer = Tx=%dk Rx=%dk\n",
3062 		      ((E1000_READ_REG(&adapter->hw, PBA) & 0xffff0000) >> 16),
3063 		      (E1000_READ_REG(&adapter->hw, PBA) & 0xffff));
3064 	device_printf(dev, "Flow control watermarks high = %d low = %d\n",
3065 		      adapter->hw.fc_high_water, adapter->hw.fc_low_water);
3066 	device_printf(dev, "tx_int_delay = %d, tx_abs_int_delay = %d\n",
3067 		      E1000_READ_REG(&adapter->hw, TIDV),
3068 		      E1000_READ_REG(&adapter->hw, TADV));
3069 	device_printf(dev, "rx_int_delay = %d, rx_abs_int_delay = %d\n",
3070 		      E1000_READ_REG(&adapter->hw, RDTR),
3071 		      E1000_READ_REG(&adapter->hw, RADV));
3072 	device_printf(dev, "fifo workaround = %lld, fifo_reset = %lld\n",
3073 		      (long long)adapter->tx_fifo_wrk_cnt,
3074 		      (long long)adapter->tx_fifo_reset_cnt);
3075 	device_printf(dev, "hw tdh = %d, hw tdt = %d\n",
3076 		      E1000_READ_REG(&adapter->hw, TDH),
3077 		      E1000_READ_REG(&adapter->hw, TDT));
3078 	device_printf(dev, "Num Tx descriptors avail = %d\n",
3079 		      adapter->num_tx_desc_avail);
3080 	device_printf(dev, "Tx Descriptors not avail1 = %ld\n",
3081 		      adapter->no_tx_desc_avail1);
3082 	device_printf(dev, "Tx Descriptors not avail2 = %ld\n",
3083 		      adapter->no_tx_desc_avail2);
3084 	device_printf(dev, "Std mbuf failed = %ld\n",
3085 		      adapter->mbuf_alloc_failed);
3086 	device_printf(dev, "Std mbuf cluster failed = %ld\n",
3087 		      adapter->mbuf_cluster_failed);
3088 	device_printf(dev, "Driver dropped packets = %ld\n",
3089 		      adapter->dropped_pkts);
3090 }
3091 
3092 static void
3093 em_print_hw_stats(struct adapter *adapter)
3094 {
3095 	device_t dev= adapter->dev;
3096 
3097 	device_printf(dev, "Adapter: %p\n", adapter);
3098 
3099 	device_printf(dev, "Excessive collisions = %lld\n",
3100 		      (long long)adapter->stats.ecol);
3101 	device_printf(dev, "Symbol errors = %lld\n",
3102 		      (long long)adapter->stats.symerrs);
3103 	device_printf(dev, "Sequence errors = %lld\n",
3104 		      (long long)adapter->stats.sec);
3105 	device_printf(dev, "Defer count = %lld\n",
3106 		      (long long)adapter->stats.dc);
3107 
3108 	device_printf(dev, "Missed Packets = %lld\n",
3109 		      (long long)adapter->stats.mpc);
3110 	device_printf(dev, "Receive No Buffers = %lld\n",
3111 		      (long long)adapter->stats.rnbc);
3112 	device_printf(dev, "Receive length errors = %lld\n",
3113 		      (long long)adapter->stats.rlec);
3114 	device_printf(dev, "Receive errors = %lld\n",
3115 		      (long long)adapter->stats.rxerrc);
3116 	device_printf(dev, "Crc errors = %lld\n",
3117 		      (long long)adapter->stats.crcerrs);
3118 	device_printf(dev, "Alignment errors = %lld\n",
3119 		      (long long)adapter->stats.algnerrc);
3120 	device_printf(dev, "Carrier extension errors = %lld\n",
3121 		      (long long)adapter->stats.cexterr);
3122 
3123 	device_printf(dev, "XON Rcvd = %lld\n",
3124 		      (long long)adapter->stats.xonrxc);
3125 	device_printf(dev, "XON Xmtd = %lld\n",
3126 		      (long long)adapter->stats.xontxc);
3127 	device_printf(dev, "XOFF Rcvd = %lld\n",
3128 		      (long long)adapter->stats.xoffrxc);
3129 	device_printf(dev, "XOFF Xmtd = %lld\n",
3130 		      (long long)adapter->stats.xofftxc);
3131 
3132 	device_printf(dev, "Good Packets Rcvd = %lld\n",
3133 		      (long long)adapter->stats.gprc);
3134 	device_printf(dev, "Good Packets Xmtd = %lld\n",
3135 		      (long long)adapter->stats.gptc);
3136 }
3137 
3138 static int
3139 em_sysctl_debug_info(SYSCTL_HANDLER_ARGS)
3140 {
3141 	int error;
3142 	int result;
3143 	struct adapter *adapter;
3144 
3145 	result = -1;
3146 	error = sysctl_handle_int(oidp, &result, 0, req);
3147 
3148 	if (error || !req->newptr)
3149 		return(error);
3150 
3151 	if (result == 1) {
3152 		adapter = (struct adapter *)arg1;
3153 		em_print_debug_info(adapter);
3154 	}
3155 
3156 	return(error);
3157 }
3158 
3159 static int
3160 em_sysctl_stats(SYSCTL_HANDLER_ARGS)
3161 {
3162 	int error;
3163 	int result;
3164 	struct adapter *adapter;
3165 
3166 	result = -1;
3167 	error = sysctl_handle_int(oidp, &result, 0, req);
3168 
3169 	if (error || !req->newptr)
3170 		return(error);
3171 
3172 	if (result == 1) {
3173 		adapter = (struct adapter *)arg1;
3174 		em_print_hw_stats(adapter);
3175 	}
3176 
3177 	return(error);
3178 }
3179 
3180 static int
3181 em_sysctl_int_delay(SYSCTL_HANDLER_ARGS)
3182 {
3183 	struct em_int_delay_info *info;
3184 	struct adapter *adapter;
3185 	uint32_t regval;
3186 	int error;
3187 	int usecs;
3188 	int ticks;
3189 
3190 	info = (struct em_int_delay_info *)arg1;
3191 	adapter = info->adapter;
3192 	usecs = info->value;
3193 	error = sysctl_handle_int(oidp, &usecs, 0, req);
3194 	if (error != 0 || req->newptr == NULL)
3195 		return(error);
3196 	if (usecs < 0 || usecs > E1000_TICKS_TO_USECS(65535))
3197 		return(EINVAL);
3198 	info->value = usecs;
3199 	ticks = E1000_USECS_TO_TICKS(usecs);
3200 
3201 	lwkt_serialize_enter(adapter->interface_data.ac_if.if_serializer);
3202 	regval = E1000_READ_OFFSET(&adapter->hw, info->offset);
3203 	regval = (regval & ~0xffff) | (ticks & 0xffff);
3204 	/* Handle a few special cases. */
3205 	switch (info->offset) {
3206 	case E1000_RDTR:
3207 	case E1000_82542_RDTR:
3208 		regval |= E1000_RDT_FPDB;
3209 		break;
3210 	case E1000_TIDV:
3211 	case E1000_82542_TIDV:
3212 		if (ticks == 0) {
3213 			adapter->txd_cmd &= ~E1000_TXD_CMD_IDE;
3214 			/* Don't write 0 into the TIDV register. */
3215 			regval++;
3216 		} else
3217 			adapter->txd_cmd |= E1000_TXD_CMD_IDE;
3218 		break;
3219 	}
3220 	E1000_WRITE_OFFSET(&adapter->hw, info->offset, regval);
3221 	lwkt_serialize_exit(adapter->interface_data.ac_if.if_serializer);
3222 	return(0);
3223 }
3224 
3225 static void
3226 em_add_int_delay_sysctl(struct adapter *adapter, const char *name,
3227 			const char *description, struct em_int_delay_info *info,
3228 			int offset, int value)
3229 {
3230 	info->adapter = adapter;
3231 	info->offset = offset;
3232 	info->value = value;
3233 	SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
3234 			SYSCTL_CHILDREN(adapter->sysctl_tree),
3235 			OID_AUTO, name, CTLTYPE_INT|CTLFLAG_RW,
3236 			info, 0, em_sysctl_int_delay, "I", description);
3237 }
3238 
3239 static int
3240 em_sysctl_int_throttle(SYSCTL_HANDLER_ARGS)
3241 {
3242 	struct adapter *adapter = (void *)arg1;
3243 	int error;
3244 	int throttle;
3245 
3246 	throttle = em_int_throttle_ceil;
3247 	error = sysctl_handle_int(oidp, &throttle, 0, req);
3248 	if (error || req->newptr == NULL)
3249 		return error;
3250 	if (throttle < 0 || throttle > 1000000000 / 256)
3251 		return EINVAL;
3252 	if (throttle) {
3253 		/*
3254 		 * Set the interrupt throttling rate in 256ns increments,
3255 		 * recalculate sysctl value assignment to get exact frequency.
3256 		 */
3257 		throttle = 1000000000 / 256 / throttle;
3258 		lwkt_serialize_enter(adapter->interface_data.ac_if.if_serializer);
3259 		em_int_throttle_ceil = 1000000000 / 256 / throttle;
3260 		E1000_WRITE_REG(&adapter->hw, ITR, throttle);
3261 		lwkt_serialize_exit(adapter->interface_data.ac_if.if_serializer);
3262 	} else {
3263 		lwkt_serialize_enter(adapter->interface_data.ac_if.if_serializer);
3264 		em_int_throttle_ceil = 0;
3265 		E1000_WRITE_REG(&adapter->hw, ITR, 0);
3266 		lwkt_serialize_exit(adapter->interface_data.ac_if.if_serializer);
3267 	}
3268 	device_printf(adapter->dev, "Interrupt moderation set to %d/sec\n",
3269 			em_int_throttle_ceil);
3270 	return 0;
3271 }
3272 
3273