xref: /dflybsd-src/sys/dev/netif/em/if_em.c (revision 52347f71f500fe4113e37cca4ea6edc6150698e7)
1 /*
2  *
3  * Copyright (c) 2004 Joerg Sonnenberger <joerg@bec.de>.  All rights reserved.
4  *
5  * Copyright (c) 2001-2006, 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 1.68 2008/04/03 12:55:15 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 #include "opt_inet.h"
98 #include "opt_serializer.h"
99 
100 #include <sys/param.h>
101 #include <sys/bus.h>
102 #include <sys/endian.h>
103 #include <sys/kernel.h>
104 #include <sys/ktr.h>
105 #include <sys/malloc.h>
106 #include <sys/mbuf.h>
107 #include <sys/module.h>
108 #include <sys/rman.h>
109 #include <sys/serialize.h>
110 #include <sys/socket.h>
111 #include <sys/sockio.h>
112 #include <sys/sysctl.h>
113 
114 #include <net/bpf.h>
115 #include <net/ethernet.h>
116 #include <net/if.h>
117 #include <net/if_arp.h>
118 #include <net/if_dl.h>
119 #include <net/if_media.h>
120 #include <net/if_types.h>
121 #include <net/ifq_var.h>
122 #include <net/vlan/if_vlan_var.h>
123 #include <net/vlan/if_vlan_ether.h>
124 
125 #ifdef INET
126 #include <netinet/in.h>
127 #include <netinet/in_systm.h>
128 #include <netinet/in_var.h>
129 #include <netinet/ip.h>
130 #include <netinet/tcp.h>
131 #include <netinet/udp.h>
132 #endif
133 
134 #include <dev/netif/em/if_em_hw.h>
135 #include <dev/netif/em/if_em.h>
136 
137 #define EM_X60_WORKAROUND
138 
139 /*********************************************************************
140  *  Set this to one to display debug statistics
141  *********************************************************************/
142 int	em_display_debug_stats = 0;
143 
144 /*********************************************************************
145  *  Driver version
146  *********************************************************************/
147 
148 char em_driver_version[] = "6.2.9";
149 
150 
151 /*********************************************************************
152  *  PCI Device ID Table
153  *
154  *  Used by probe to select devices to load on
155  *  Last field stores an index into em_strings
156  *  Last entry must be all 0s
157  *
158  *  { Vendor ID, Device ID, SubVendor ID, SubDevice ID, String Index }
159  *********************************************************************/
160 
161 static em_vendor_info_t em_vendor_info_array[] =
162 {
163 	/* Intel(R) PRO/1000 Network Connection */
164 	{ 0x8086, E1000_DEV_ID_82540EM,		PCI_ANY_ID, PCI_ANY_ID, 0},
165 	{ 0x8086, E1000_DEV_ID_82540EM_LOM,	PCI_ANY_ID, PCI_ANY_ID, 0},
166 	{ 0x8086, E1000_DEV_ID_82540EP,		PCI_ANY_ID, PCI_ANY_ID, 0},
167 	{ 0x8086, E1000_DEV_ID_82540EP_LOM,	PCI_ANY_ID, PCI_ANY_ID, 0},
168 	{ 0x8086, E1000_DEV_ID_82540EP_LP,	PCI_ANY_ID, PCI_ANY_ID, 0},
169 
170 	{ 0x8086, E1000_DEV_ID_82541EI,		PCI_ANY_ID, PCI_ANY_ID, 0},
171 	{ 0x8086, E1000_DEV_ID_82541ER,		PCI_ANY_ID, PCI_ANY_ID, 0},
172 	{ 0x8086, E1000_DEV_ID_82541ER_LOM,	PCI_ANY_ID, PCI_ANY_ID, 0},
173 	{ 0x8086, E1000_DEV_ID_82541EI_MOBILE,	PCI_ANY_ID, PCI_ANY_ID, 0},
174 	{ 0x8086, E1000_DEV_ID_82541GI,		PCI_ANY_ID, PCI_ANY_ID, 0},
175 	{ 0x8086, E1000_DEV_ID_82541GI_LF,	PCI_ANY_ID, PCI_ANY_ID, 0},
176 	{ 0x8086, E1000_DEV_ID_82541GI_MOBILE,	PCI_ANY_ID, PCI_ANY_ID, 0},
177 
178 	{ 0x8086, E1000_DEV_ID_82542,		PCI_ANY_ID, PCI_ANY_ID, 0},
179 
180 	{ 0x8086, E1000_DEV_ID_82543GC_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
181 	{ 0x8086, E1000_DEV_ID_82543GC_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
182 
183 	{ 0x8086, E1000_DEV_ID_82544EI_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
184 	{ 0x8086, E1000_DEV_ID_82544EI_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
185 	{ 0x8086, E1000_DEV_ID_82544GC_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
186 	{ 0x8086, E1000_DEV_ID_82544GC_LOM,	PCI_ANY_ID, PCI_ANY_ID, 0},
187 
188 	{ 0x8086, E1000_DEV_ID_82545EM_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
189 	{ 0x8086, E1000_DEV_ID_82545EM_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
190 	{ 0x8086, E1000_DEV_ID_82545GM_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
191 	{ 0x8086, E1000_DEV_ID_82545GM_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
192 	{ 0x8086, E1000_DEV_ID_82545GM_SERDES,	PCI_ANY_ID, PCI_ANY_ID, 0},
193 
194 	{ 0x8086, E1000_DEV_ID_82546EB_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
195 	{ 0x8086, E1000_DEV_ID_82546EB_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
196 	{ 0x8086, E1000_DEV_ID_82546EB_QUAD_COPPER, PCI_ANY_ID, PCI_ANY_ID, 0},
197 	{ 0x8086, E1000_DEV_ID_82546GB_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
198 	{ 0x8086, E1000_DEV_ID_82546GB_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
199 	{ 0x8086, E1000_DEV_ID_82546GB_SERDES,	PCI_ANY_ID, PCI_ANY_ID, 0},
200 	{ 0x8086, E1000_DEV_ID_82546GB_PCIE,	PCI_ANY_ID, PCI_ANY_ID, 0},
201 	{ 0x8086, E1000_DEV_ID_82546GB_QUAD_COPPER, PCI_ANY_ID, PCI_ANY_ID, 0},
202 	{ 0x8086, E1000_DEV_ID_82546GB_QUAD_COPPER_KSP3,
203 						PCI_ANY_ID, PCI_ANY_ID, 0},
204 
205 	{ 0x8086, E1000_DEV_ID_82547EI,		PCI_ANY_ID, PCI_ANY_ID, 0},
206 	{ 0x8086, E1000_DEV_ID_82547EI_MOBILE,	PCI_ANY_ID, PCI_ANY_ID, 0},
207 	{ 0x8086, E1000_DEV_ID_82547GI,		PCI_ANY_ID, PCI_ANY_ID, 0},
208 
209 	{ 0x8086, E1000_DEV_ID_82571EB_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
210 	{ 0x8086, E1000_DEV_ID_82571EB_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
211 	{ 0x8086, E1000_DEV_ID_82571EB_SERDES,	PCI_ANY_ID, PCI_ANY_ID, 0},
212 	{ 0x8086, E1000_DEV_ID_82571EB_QUAD_COPPER,
213 						PCI_ANY_ID, PCI_ANY_ID, 0},
214 	{ 0x8086, E1000_DEV_ID_82571EB_QUAD_COPPER_LOWPROFILE,
215 						PCI_ANY_ID, PCI_ANY_ID, 0},
216 
217 	{ 0x8086, E1000_DEV_ID_82571EB_QUAD_FIBER,
218 						PCI_ANY_ID, PCI_ANY_ID, 0},
219 	{ 0x8086, E1000_DEV_ID_82571PT_QUAD_COPPER,
220 						PCI_ANY_ID, PCI_ANY_ID, 0},
221 	{ 0x8086, E1000_DEV_ID_82572EI_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
222 	{ 0x8086, E1000_DEV_ID_82572EI_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
223 	{ 0x8086, E1000_DEV_ID_82572EI_SERDES,	PCI_ANY_ID, PCI_ANY_ID, 0},
224 	{ 0x8086, E1000_DEV_ID_82572EI,		PCI_ANY_ID, PCI_ANY_ID, 0},
225 
226 	{ 0x8086, E1000_DEV_ID_82573E,		PCI_ANY_ID, PCI_ANY_ID, 0},
227 	{ 0x8086, E1000_DEV_ID_82573E_IAMT,	PCI_ANY_ID, PCI_ANY_ID, 0},
228 	{ 0x8086, E1000_DEV_ID_82573L,		PCI_ANY_ID, PCI_ANY_ID, 0},
229 
230 	{ 0x8086, E1000_DEV_ID_80003ES2LAN_COPPER_SPT,
231 						PCI_ANY_ID, PCI_ANY_ID, 0},
232 	{ 0x8086, E1000_DEV_ID_80003ES2LAN_SERDES_SPT,
233 						PCI_ANY_ID, PCI_ANY_ID, 0},
234 	{ 0x8086, E1000_DEV_ID_80003ES2LAN_COPPER_DPT,
235 						PCI_ANY_ID, PCI_ANY_ID, 0},
236 	{ 0x8086, E1000_DEV_ID_80003ES2LAN_SERDES_DPT,
237 						PCI_ANY_ID, PCI_ANY_ID, 0},
238 
239 	{ 0x8086, E1000_DEV_ID_ICH8_IGP_M_AMT,	PCI_ANY_ID, PCI_ANY_ID, 0},
240 	{ 0x8086, E1000_DEV_ID_ICH8_IGP_AMT,	PCI_ANY_ID, PCI_ANY_ID, 0},
241 	{ 0x8086, E1000_DEV_ID_ICH8_IGP_C,	PCI_ANY_ID, PCI_ANY_ID, 0},
242 	{ 0x8086, E1000_DEV_ID_ICH8_IFE,	PCI_ANY_ID, PCI_ANY_ID, 0},
243 	{ 0x8086, E1000_DEV_ID_ICH8_IFE_GT,	PCI_ANY_ID, PCI_ANY_ID, 0},
244 	{ 0x8086, E1000_DEV_ID_ICH8_IFE_G,	PCI_ANY_ID, PCI_ANY_ID, 0},
245 	{ 0x8086, E1000_DEV_ID_ICH8_IGP_M,	PCI_ANY_ID, PCI_ANY_ID, 0},
246 
247 	{ 0x8086, E1000_DEV_ID_ICH9_IGP_AMT,	PCI_ANY_ID, PCI_ANY_ID, 0},
248 	{ 0x8086, E1000_DEV_ID_ICH9_IGP_C,	PCI_ANY_ID, PCI_ANY_ID, 0},
249 	{ 0x8086, E1000_DEV_ID_ICH9_IFE,	PCI_ANY_ID, PCI_ANY_ID, 0},
250 	{ 0x8086, E1000_DEV_ID_ICH9_IFE_GT,	PCI_ANY_ID, PCI_ANY_ID, 0},
251 	{ 0x8086, E1000_DEV_ID_ICH9_IFE_G,	PCI_ANY_ID, PCI_ANY_ID, 0},
252 
253 	{ 0x8086, E1000_DEV_ID_82575EB_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
254 	{ 0x8086, E1000_DEV_ID_82575EB_FIBER_SERDES,
255 						PCI_ANY_ID, PCI_ANY_ID, 0},
256 	{ 0x8086, E1000_DEV_ID_82575GB_QUAD_COPPER,
257 						PCI_ANY_ID, PCI_ANY_ID, 0},
258 	{ 0x8086, 0x101A, PCI_ANY_ID, PCI_ANY_ID, 0},
259 	{ 0x8086, 0x1014, PCI_ANY_ID, PCI_ANY_ID, 0},
260 	/* required last entry */
261 	{ 0, 0, 0, 0, 0}
262 };
263 
264 /*********************************************************************
265  *  Table of branding strings for all supported NICs.
266  *********************************************************************/
267 
268 static const char *em_strings[] = {
269 	"Intel(R) PRO/1000 Network Connection"
270 };
271 
272 /*********************************************************************
273  *  Function prototypes
274  *********************************************************************/
275 static int	em_probe(device_t);
276 static int	em_attach(device_t);
277 static int	em_detach(device_t);
278 static int	em_shutdown(device_t);
279 static void	em_intr(void *);
280 static int	em_suspend(device_t);
281 static int	em_resume(device_t);
282 static void	em_start(struct ifnet *);
283 static int	em_ioctl(struct ifnet *, u_long, caddr_t, struct ucred *);
284 static void	em_watchdog(struct ifnet *);
285 static void	em_init(void *);
286 static void	em_stop(void *);
287 static void	em_media_status(struct ifnet *, struct ifmediareq *);
288 static int	em_media_change(struct ifnet *);
289 static void	em_identify_hardware(struct adapter *);
290 static int	em_allocate_pci_resources(device_t);
291 static void	em_free_pci_resources(device_t);
292 static void	em_local_timer(void *);
293 static int	em_hardware_init(struct adapter *);
294 static void	em_setup_interface(device_t, struct adapter *);
295 static int	em_setup_transmit_structures(struct adapter *);
296 static void	em_initialize_transmit_unit(struct adapter *);
297 static int	em_setup_receive_structures(struct adapter *);
298 static void	em_initialize_receive_unit(struct adapter *);
299 static void	em_enable_intr(struct adapter *);
300 static void	em_disable_intr(struct adapter *);
301 static void	em_free_transmit_structures(struct adapter *);
302 static void	em_free_receive_structures(struct adapter *);
303 static void	em_update_stats_counters(struct adapter *);
304 static void	em_txeof(struct adapter *);
305 static int	em_allocate_receive_structures(struct adapter *);
306 static void	em_rxeof(struct adapter *, int);
307 static void	em_receive_checksum(struct adapter *, struct em_rx_desc *,
308 				    struct mbuf *);
309 static void	em_transmit_checksum_setup(struct adapter *, struct mbuf *,
310 					   uint32_t *, uint32_t *);
311 static void	em_set_promisc(struct adapter *);
312 static void	em_disable_promisc(struct adapter *);
313 static void	em_set_multi(struct adapter *);
314 static void	em_print_hw_stats(struct adapter *);
315 static void	em_update_link_status(struct adapter *);
316 static int	em_get_buf(int i, struct adapter *, struct mbuf *, int how);
317 static void	em_enable_vlans(struct adapter *);
318 static void	em_disable_vlans(struct adapter *);
319 static int	em_encap(struct adapter *, struct mbuf *);
320 static void	em_smartspeed(struct adapter *);
321 static int	em_82547_fifo_workaround(struct adapter *, int);
322 static void	em_82547_update_fifo_head(struct adapter *, int);
323 static int	em_82547_tx_fifo_reset(struct adapter *);
324 static void	em_82547_move_tail(void *);
325 static void	em_82547_move_tail_serialized(struct adapter *);
326 static int	em_dma_malloc(struct adapter *, bus_size_t,
327 			      struct em_dma_alloc *);
328 static void	em_dma_free(struct adapter *, struct em_dma_alloc *);
329 static void	em_print_debug_info(struct adapter *);
330 static int	em_is_valid_ether_addr(uint8_t *);
331 static int	em_sysctl_stats(SYSCTL_HANDLER_ARGS);
332 static int	em_sysctl_debug_info(SYSCTL_HANDLER_ARGS);
333 static uint32_t	em_fill_descriptors(bus_addr_t address, uint32_t length,
334 				   PDESC_ARRAY desc_array);
335 static int	em_sysctl_int_delay(SYSCTL_HANDLER_ARGS);
336 static int	em_sysctl_int_throttle(SYSCTL_HANDLER_ARGS);
337 static void	em_add_int_delay_sysctl(struct adapter *, const char *,
338 					const char *,
339 					struct em_int_delay_info *, int, int);
340 
341 /*********************************************************************
342  *  FreeBSD Device Interface Entry Points
343  *********************************************************************/
344 
345 static device_method_t em_methods[] = {
346 	/* Device interface */
347 	DEVMETHOD(device_probe, em_probe),
348 	DEVMETHOD(device_attach, em_attach),
349 	DEVMETHOD(device_detach, em_detach),
350 	DEVMETHOD(device_shutdown, em_shutdown),
351 	DEVMETHOD(device_suspend, em_suspend),
352 	DEVMETHOD(device_resume, em_resume),
353 	{0, 0}
354 };
355 
356 static driver_t em_driver = {
357 	"em", em_methods, sizeof(struct adapter),
358 };
359 
360 static devclass_t em_devclass;
361 
362 DECLARE_DUMMY_MODULE(if_em);
363 DRIVER_MODULE(if_em, pci, em_driver, em_devclass, 0, 0);
364 
365 /*********************************************************************
366  *  Tunable default values.
367  *********************************************************************/
368 
369 #define E1000_TICKS_TO_USECS(ticks)	((1024 * (ticks) + 500) / 1000)
370 #define E1000_USECS_TO_TICKS(usecs)	((1000 * (usecs) + 512) / 1024)
371 
372 static int em_tx_int_delay_dflt = E1000_TICKS_TO_USECS(EM_TIDV);
373 static int em_rx_int_delay_dflt = E1000_TICKS_TO_USECS(EM_RDTR);
374 static int em_tx_abs_int_delay_dflt = E1000_TICKS_TO_USECS(EM_TADV);
375 static int em_rx_abs_int_delay_dflt = E1000_TICKS_TO_USECS(EM_RADV);
376 static int em_int_throttle_ceil = 10000;
377 static int em_rxd = EM_DEFAULT_RXD;
378 static int em_txd = EM_DEFAULT_TXD;
379 static int em_smart_pwr_down = FALSE;
380 
381 TUNABLE_INT("hw.em.tx_int_delay", &em_tx_int_delay_dflt);
382 TUNABLE_INT("hw.em.rx_int_delay", &em_rx_int_delay_dflt);
383 TUNABLE_INT("hw.em.tx_abs_int_delay", &em_tx_abs_int_delay_dflt);
384 TUNABLE_INT("hw.em.rx_abs_int_delay", &em_rx_abs_int_delay_dflt);
385 TUNABLE_INT("hw.em.int_throttle_ceil", &em_int_throttle_ceil);
386 TUNABLE_INT("hw.em.rxd", &em_rxd);
387 TUNABLE_INT("hw.em.txd", &em_txd);
388 TUNABLE_INT("hw.em.smart_pwr_down", &em_smart_pwr_down);
389 
390 /*
391  * Kernel trace for characterization of operations
392  */
393 #if !defined(KTR_IF_EM)
394 #define KTR_IF_EM	KTR_ALL
395 #endif
396 KTR_INFO_MASTER(if_em);
397 KTR_INFO(KTR_IF_EM, if_em, intr_beg, 0, "intr begin", 0);
398 KTR_INFO(KTR_IF_EM, if_em, intr_end, 1, "intr end", 0);
399 #ifdef DEVICE_POLLING
400 KTR_INFO(KTR_IF_EM, if_em, poll_beg, 2, "poll begin", 0);
401 KTR_INFO(KTR_IF_EM, if_em, poll_end, 3, "poll end", 0);
402 #endif
403 KTR_INFO(KTR_IF_EM, if_em, pkt_receive, 4, "rx packet", 0);
404 KTR_INFO(KTR_IF_EM, if_em, pkt_txqueue, 5, "tx packet", 0);
405 KTR_INFO(KTR_IF_EM, if_em, pkt_txclean, 6, "tx clean", 0);
406 #define logif(name)	KTR_LOG(if_em_ ## name)
407 
408 /*********************************************************************
409  *  Device identification routine
410  *
411  *  em_probe determines if the driver should be loaded on
412  *  adapter based on PCI vendor/device id of the adapter.
413  *
414  *  return 0 on success, positive on failure
415  *********************************************************************/
416 
417 static int
418 em_probe(device_t dev)
419 {
420 	em_vendor_info_t *ent;
421 
422 	uint16_t pci_vendor_id = 0;
423 	uint16_t pci_device_id = 0;
424 	uint16_t pci_subvendor_id = 0;
425 	uint16_t pci_subdevice_id = 0;
426 	char adapter_name[60];
427 
428 	INIT_DEBUGOUT("em_probe: begin");
429 
430 	pci_vendor_id = pci_get_vendor(dev);
431 	if (pci_vendor_id != EM_VENDOR_ID)
432 		return (ENXIO);
433 
434 	pci_device_id = pci_get_device(dev);
435 	pci_subvendor_id = pci_get_subvendor(dev);
436 	pci_subdevice_id = pci_get_subdevice(dev);
437 
438 	ent = em_vendor_info_array;
439 	while (ent->vendor_id != 0) {
440 		if ((pci_vendor_id == ent->vendor_id) &&
441 		    (pci_device_id == ent->device_id) &&
442 
443 		    ((pci_subvendor_id == ent->subvendor_id) ||
444 		     (ent->subvendor_id == PCI_ANY_ID)) &&
445 
446 		    ((pci_subdevice_id == ent->subdevice_id) ||
447 		     (ent->subdevice_id == PCI_ANY_ID))) {
448 			ksnprintf(adapter_name, sizeof(adapter_name),
449 				 "%s, Version - %s",  em_strings[ent->index],
450 				 em_driver_version);
451 			device_set_desc_copy(dev, adapter_name);
452 			device_set_async_attach(dev, TRUE);
453 			return (0);
454 		}
455 		ent++;
456 	}
457 
458 	return (ENXIO);
459 }
460 
461 /*********************************************************************
462  *  Device initialization routine
463  *
464  *  The attach entry point is called when the driver is being loaded.
465  *  This routine identifies the type of hardware, allocates all resources
466  *  and initializes the hardware.
467  *
468  *  return 0 on success, positive on failure
469  *********************************************************************/
470 
471 static int
472 em_attach(device_t dev)
473 {
474 	struct adapter *adapter;
475 	int tsize, rsize;
476 	int error = 0;
477 
478 	INIT_DEBUGOUT("em_attach: begin");
479 
480 	adapter = device_get_softc(dev);
481 
482 	callout_init(&adapter->timer);
483 	callout_init(&adapter->tx_fifo_timer);
484 
485 	adapter->dev = dev;
486 	adapter->osdep.dev = dev;
487 
488 	/* SYSCTL stuff */
489 	sysctl_ctx_init(&adapter->sysctl_ctx);
490 	adapter->sysctl_tree = SYSCTL_ADD_NODE(&adapter->sysctl_ctx,
491 					       SYSCTL_STATIC_CHILDREN(_hw),
492 					       OID_AUTO,
493 					       device_get_nameunit(dev),
494 					       CTLFLAG_RD,
495 					       0, "");
496 
497 	if (adapter->sysctl_tree == NULL) {
498 		device_printf(dev, "Unable to create sysctl tree\n");
499 		return EIO;
500 	}
501 
502 	SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
503 			SYSCTL_CHILDREN(adapter->sysctl_tree),
504 			OID_AUTO, "debug_info", CTLTYPE_INT|CTLFLAG_RW,
505 			(void *)adapter, 0,
506 			em_sysctl_debug_info, "I", "Debug Information");
507 
508 	SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
509 			SYSCTL_CHILDREN(adapter->sysctl_tree),
510 			OID_AUTO, "stats", CTLTYPE_INT|CTLFLAG_RW,
511 			(void *)adapter, 0,
512 			em_sysctl_stats, "I", "Statistics");
513 
514 	/* Determine hardware revision */
515 	em_identify_hardware(adapter);
516 
517 	/* Set up some sysctls for the tunable interrupt delays */
518 	em_add_int_delay_sysctl(adapter, "rx_int_delay",
519 				"receive interrupt delay in usecs",
520 				&adapter->rx_int_delay,
521 				E1000_REG_OFFSET(&adapter->hw, RDTR),
522 				em_rx_int_delay_dflt);
523 	em_add_int_delay_sysctl(adapter, "tx_int_delay",
524 				"transmit interrupt delay in usecs",
525 				&adapter->tx_int_delay,
526 				E1000_REG_OFFSET(&adapter->hw, TIDV),
527 				em_tx_int_delay_dflt);
528 	if (adapter->hw.mac_type >= em_82540) {
529 		em_add_int_delay_sysctl(adapter, "rx_abs_int_delay",
530 					"receive interrupt delay limit in usecs",
531 					&adapter->rx_abs_int_delay,
532 					E1000_REG_OFFSET(&adapter->hw, RADV),
533 					em_rx_abs_int_delay_dflt);
534 		em_add_int_delay_sysctl(adapter, "tx_abs_int_delay",
535 					"transmit interrupt delay limit in usecs",
536 					&adapter->tx_abs_int_delay,
537 					E1000_REG_OFFSET(&adapter->hw, TADV),
538 					em_tx_abs_int_delay_dflt);
539 		SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
540 			SYSCTL_CHILDREN(adapter->sysctl_tree),
541 			OID_AUTO, "int_throttle_ceil", CTLTYPE_INT|CTLFLAG_RW,
542 			adapter, 0, em_sysctl_int_throttle, "I", NULL);
543 	}
544 
545 	/*
546 	 * Validate number of transmit and receive descriptors. It
547 	 * must not exceed hardware maximum, and must be multiple
548 	 * of EM_DBA_ALIGN.
549 	 */
550 	if (((em_txd * sizeof(struct em_tx_desc)) % EM_DBA_ALIGN) != 0 ||
551 	    (adapter->hw.mac_type >= em_82544 && em_txd > EM_MAX_TXD) ||
552 	    (adapter->hw.mac_type < em_82544 && em_txd > EM_MAX_TXD_82543) ||
553 	    (em_txd < EM_MIN_TXD)) {
554 		device_printf(dev, "Using %d TX descriptors instead of %d!\n",
555 			      EM_DEFAULT_TXD, em_txd);
556 		adapter->num_tx_desc = EM_DEFAULT_TXD;
557 	} else {
558 		adapter->num_tx_desc = em_txd;
559 	}
560 
561 	if (((em_rxd * sizeof(struct em_rx_desc)) % EM_DBA_ALIGN) != 0 ||
562 	    (adapter->hw.mac_type >= em_82544 && em_rxd > EM_MAX_RXD) ||
563 	    (adapter->hw.mac_type < em_82544 && em_rxd > EM_MAX_RXD_82543) ||
564 	    (em_rxd < EM_MIN_RXD)) {
565 		device_printf(dev, "Using %d RX descriptors instead of %d!\n",
566 			      EM_DEFAULT_RXD, em_rxd);
567 		adapter->num_rx_desc = EM_DEFAULT_RXD;
568 	} else {
569 		adapter->num_rx_desc = em_rxd;
570 	}
571 
572 	SYSCTL_ADD_INT(&adapter->sysctl_ctx,
573 		       SYSCTL_CHILDREN(adapter->sysctl_tree), OID_AUTO, "rxd",
574 		       CTLFLAG_RD, &adapter->num_rx_desc, 0, NULL);
575 	SYSCTL_ADD_INT(&adapter->sysctl_ctx,
576 		       SYSCTL_CHILDREN(adapter->sysctl_tree), OID_AUTO, "txd",
577 		       CTLFLAG_RD, &adapter->num_tx_desc, 0, NULL);
578 
579 	adapter->hw.autoneg = DO_AUTO_NEG;
580 	adapter->hw.wait_autoneg_complete = WAIT_FOR_AUTO_NEG_DEFAULT;
581 	adapter->hw.autoneg_advertised = AUTONEG_ADV_DEFAULT;
582 	adapter->hw.tbi_compatibility_en = TRUE;
583 	adapter->rx_buffer_len = EM_RXBUFFER_2048;
584 
585 	adapter->hw.phy_init_script = 1;
586 	adapter->hw.phy_reset_disable = FALSE;
587 
588 #ifndef EM_MASTER_SLAVE
589 	adapter->hw.master_slave = em_ms_hw_default;
590 #else
591 	adapter->hw.master_slave = EM_MASTER_SLAVE;
592 #endif
593 
594 	/*
595 	 * Set the max frame size assuming standard ethernet
596 	 * sized frames.
597 	 */
598 	adapter->hw.max_frame_size = ETHERMTU + ETHER_HDR_LEN + ETHER_CRC_LEN;
599 
600 	adapter->hw.min_frame_size =
601 	    MINIMUM_ETHERNET_PACKET_SIZE + ETHER_CRC_LEN;
602 
603 	/*
604 	 * This controls when hardware reports transmit completion
605 	 * status.
606 	 */
607 	adapter->hw.report_tx_early = 1;
608 
609 	error = em_allocate_pci_resources(dev);
610 	if (error)
611 		goto fail;
612 
613 	/* Initialize eeprom parameters */
614 	em_init_eeprom_params(&adapter->hw);
615 
616 	tsize = roundup2(adapter->num_tx_desc * sizeof(struct em_tx_desc),
617 			 EM_DBA_ALIGN);
618 
619 	/* Allocate Transmit Descriptor ring */
620 	error = em_dma_malloc(adapter, tsize, &adapter->txdma);
621 	if (error) {
622 		device_printf(dev, "Unable to allocate TxDescriptor memory\n");
623 		goto fail;
624 	}
625 	adapter->tx_desc_base = (struct em_tx_desc *)adapter->txdma.dma_vaddr;
626 
627 	rsize = roundup2(adapter->num_rx_desc * sizeof(struct em_rx_desc),
628 			 EM_DBA_ALIGN);
629 
630 	/* Allocate Receive Descriptor ring */
631 	error = em_dma_malloc(adapter, rsize, &adapter->rxdma);
632 	if (error) {
633 		device_printf(dev, "Unable to allocate rx_desc memory\n");
634 		goto fail;
635 	}
636 	adapter->rx_desc_base = (struct em_rx_desc *)adapter->rxdma.dma_vaddr;
637 
638 	/* Initialize the hardware */
639 	if (em_hardware_init(adapter)) {
640 		device_printf(dev, "Unable to initialize the hardware\n");
641 		error = EIO;
642 		goto fail;
643 	}
644 
645 	/* Copy the permanent MAC address out of the EEPROM */
646 	if (em_read_mac_addr(&adapter->hw) < 0) {
647 		device_printf(dev,
648 			      "EEPROM read error while reading MAC address\n");
649 		error = EIO;
650 		goto fail;
651 	}
652 
653 	if (!em_is_valid_ether_addr(adapter->hw.mac_addr)) {
654 		device_printf(dev, "Invalid MAC address\n");
655 		error = EIO;
656 		goto fail;
657 	}
658 
659 	/* Setup OS specific network interface */
660 	em_setup_interface(dev, adapter);
661 
662 	/* Initialize statistics */
663 	em_clear_hw_cntrs(&adapter->hw);
664 	em_update_stats_counters(adapter);
665 	adapter->hw.get_link_status = 1;
666 	em_update_link_status(adapter);
667 
668 	/* Indicate SOL/IDER usage */
669 	if (em_check_phy_reset_block(&adapter->hw)) {
670 		device_printf(dev, "PHY reset is blocked due to "
671 			      "SOL/IDER session.\n");
672 	}
673 
674 	/* Identify 82544 on PCIX */
675 	em_get_bus_info(&adapter->hw);
676 	if (adapter->hw.bus_type == em_bus_type_pcix &&
677 	    adapter->hw.mac_type == em_82544)
678 		adapter->pcix_82544 = TRUE;
679 	else
680 		adapter->pcix_82544 = FALSE;
681 
682 	error = bus_setup_intr(dev, adapter->res_interrupt, INTR_NETSAFE,
683 			   em_intr, adapter,
684 			   &adapter->int_handler_tag,
685 			   adapter->interface_data.ac_if.if_serializer);
686 	if (error) {
687 		device_printf(dev, "Error registering interrupt handler!\n");
688 		ether_ifdetach(&adapter->interface_data.ac_if);
689 		goto fail;
690 	}
691 
692 	INIT_DEBUGOUT("em_attach: end");
693 	return(0);
694 
695 fail:
696 	em_detach(dev);
697 	return(error);
698 }
699 
700 /*********************************************************************
701  *  Device removal routine
702  *
703  *  The detach entry point is called when the driver is being removed.
704  *  This routine stops the adapter and deallocates all the resources
705  *  that were allocated for driver operation.
706  *
707  *  return 0 on success, positive on failure
708  *********************************************************************/
709 
710 static int
711 em_detach(device_t dev)
712 {
713 	struct adapter *adapter = device_get_softc(dev);
714 
715 	INIT_DEBUGOUT("em_detach: begin");
716 
717 	if (device_is_attached(dev)) {
718 		struct ifnet *ifp = &adapter->interface_data.ac_if;
719 
720 		lwkt_serialize_enter(ifp->if_serializer);
721 		adapter->in_detach = 1;
722 		em_stop(adapter);
723 		em_phy_hw_reset(&adapter->hw);
724 		bus_teardown_intr(dev, adapter->res_interrupt,
725 				  adapter->int_handler_tag);
726 		lwkt_serialize_exit(ifp->if_serializer);
727 
728 		ether_ifdetach(ifp);
729 	}
730 	bus_generic_detach(dev);
731 
732 	em_free_pci_resources(dev);
733 
734 	/* Free Transmit Descriptor ring */
735 	if (adapter->tx_desc_base != NULL) {
736 		em_dma_free(adapter, &adapter->txdma);
737 		adapter->tx_desc_base = NULL;
738 	}
739 
740 	/* Free Receive Descriptor ring */
741 	if (adapter->rx_desc_base != NULL) {
742 		em_dma_free(adapter, &adapter->rxdma);
743 		adapter->rx_desc_base = NULL;
744 	}
745 
746 	/* Free sysctl tree */
747 	if (adapter->sysctl_tree != NULL) {
748 		adapter->sysctl_tree = NULL;
749 		sysctl_ctx_free(&adapter->sysctl_ctx);
750 	}
751 
752 	return (0);
753 }
754 
755 /*********************************************************************
756  *
757  *  Shutdown entry point
758  *
759  **********************************************************************/
760 
761 static int
762 em_shutdown(device_t dev)
763 {
764 	struct adapter *adapter = device_get_softc(dev);
765 	struct ifnet *ifp = &adapter->interface_data.ac_if;
766 
767 	lwkt_serialize_enter(ifp->if_serializer);
768 	em_stop(adapter);
769 	lwkt_serialize_exit(ifp->if_serializer);
770 
771 	return (0);
772 }
773 
774 /*
775  * Suspend/resume device methods.
776  */
777 static int
778 em_suspend(device_t dev)
779 {
780 	struct adapter *adapter = device_get_softc(dev);
781 	struct ifnet *ifp = &adapter->interface_data.ac_if;
782 
783 	lwkt_serialize_enter(ifp->if_serializer);
784 	em_stop(adapter);
785 	lwkt_serialize_exit(ifp->if_serializer);
786 	return (0);
787 }
788 
789 static int
790 em_resume(device_t dev)
791 {
792 	struct adapter *adapter = device_get_softc(dev);
793 	struct ifnet *ifp = &adapter->interface_data.ac_if;
794 
795 	lwkt_serialize_enter(ifp->if_serializer);
796 	ifp->if_flags &= ~IFF_RUNNING;
797 	em_init(adapter);
798 	if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) == (IFF_UP | IFF_RUNNING))
799 		em_start(ifp);
800 	lwkt_serialize_exit(ifp->if_serializer);
801 
802 	return bus_generic_resume(dev);
803 }
804 
805 /*********************************************************************
806  *  Transmit entry point
807  *
808  *  em_start is called by the stack to initiate a transmit.
809  *  The driver will remain in this routine as long as there are
810  *  packets to transmit and transmit resources are available.
811  *  In case resources are not available stack is notified and
812  *  the packet is requeued.
813  **********************************************************************/
814 
815 static void
816 em_start(struct ifnet *ifp)
817 {
818 	struct mbuf *m_head;
819 	struct adapter *adapter = ifp->if_softc;
820 
821 	ASSERT_SERIALIZED(ifp->if_serializer);
822 
823 	if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
824 		return;
825 	if (!adapter->link_active)
826 		return;
827 	while (!ifq_is_empty(&ifp->if_snd)) {
828 		m_head = ifq_poll(&ifp->if_snd);
829 
830 		if (m_head == NULL)
831 			break;
832 
833 		logif(pkt_txqueue);
834 		if (em_encap(adapter, m_head)) {
835 			ifp->if_flags |= IFF_OACTIVE;
836 			break;
837 		}
838 		ifq_dequeue(&ifp->if_snd, m_head);
839 
840 		/* Send a copy of the frame to the BPF listener */
841 		ETHER_BPF_MTAP(ifp, m_head);
842 
843 		/* Set timeout in case hardware has problems transmitting. */
844 		ifp->if_timer = EM_TX_TIMEOUT;
845 	}
846 }
847 
848 /*********************************************************************
849  *  Ioctl entry point
850  *
851  *  em_ioctl is called when the user wants to configure the
852  *  interface.
853  *
854  *  return 0 on success, positive on failure
855  **********************************************************************/
856 
857 static int
858 em_ioctl(struct ifnet *ifp, u_long command, caddr_t data, struct ucred *cr)
859 {
860 	int max_frame_size, mask, error = 0, reinit = 0;
861 	struct ifreq *ifr = (struct ifreq *) data;
862 	struct adapter *adapter = ifp->if_softc;
863 	uint16_t eeprom_data = 0;
864 
865 	ASSERT_SERIALIZED(ifp->if_serializer);
866 
867 	if (adapter->in_detach)
868 		return 0;
869 
870 	switch (command) {
871 	case SIOCSIFMTU:
872 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOCSIFMTU (Set Interface MTU)");
873 		switch (adapter->hw.mac_type) {
874 		case em_82573:
875 			/*
876 			 * 82573 only supports jumbo frames
877 			 * if ASPM is disabled.
878 			 */
879 			em_read_eeprom(&adapter->hw, EEPROM_INIT_3GIO_3,
880 			    1, &eeprom_data);
881 			if (eeprom_data & EEPROM_WORD1A_ASPM_MASK) {
882 				max_frame_size = ETHER_MAX_LEN;
883 				break;
884 			}
885 			/* Allow Jumbo frames */
886 			/* FALLTHROUGH */
887 		case em_82571:
888 		case em_82572:
889 		case em_ich9lan:
890 		case em_80003es2lan:	/* Limit Jumbo Frame size */
891 			max_frame_size = 9234;
892 			break;
893 		case em_ich8lan:
894 			/* ICH8 does not support jumbo frames */
895 			max_frame_size = ETHER_MAX_LEN;
896 			break;
897 		default:
898 			max_frame_size = MAX_JUMBO_FRAME_SIZE;
899 			break;
900 		}
901 		if (ifr->ifr_mtu >
902 			max_frame_size - ETHER_HDR_LEN - ETHER_CRC_LEN) {
903 			error = EINVAL;
904 		} else {
905 			ifp->if_mtu = ifr->ifr_mtu;
906 			adapter->hw.max_frame_size =
907 			ifp->if_mtu + ETHER_HDR_LEN + ETHER_CRC_LEN;
908 			ifp->if_flags &= ~IFF_RUNNING;
909 			em_init(adapter);
910 		}
911 		break;
912 	case SIOCSIFFLAGS:
913 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOCSIFFLAGS "
914 			       "(Set Interface Flags)");
915 		if (ifp->if_flags & IFF_UP) {
916 			if (!(ifp->if_flags & IFF_RUNNING)) {
917 				em_init(adapter);
918 			} else if ((ifp->if_flags ^ adapter->if_flags) &
919 				   IFF_PROMISC) {
920 				em_disable_promisc(adapter);
921 				em_set_promisc(adapter);
922 			}
923 		} else {
924 			if (ifp->if_flags & IFF_RUNNING)
925 				em_stop(adapter);
926 		}
927 		adapter->if_flags = ifp->if_flags;
928 		break;
929 	case SIOCADDMULTI:
930 	case SIOCDELMULTI:
931 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOC(ADD|DEL)MULTI");
932 		if (ifp->if_flags & IFF_RUNNING) {
933 			em_disable_intr(adapter);
934 			em_set_multi(adapter);
935 			if (adapter->hw.mac_type == em_82542_rev2_0)
936 				em_initialize_receive_unit(adapter);
937 #ifdef DEVICE_POLLING
938 			/* Do not enable interrupt if polling(4) is enabled */
939 			if ((ifp->if_flags & IFF_POLLING) == 0)
940 #endif
941 			em_enable_intr(adapter);
942 		}
943 		break;
944 	case SIOCSIFMEDIA:
945 		/* Check SOL/IDER usage */
946 		if (em_check_phy_reset_block(&adapter->hw)) {
947 			if_printf(ifp, "Media change is blocked due to "
948 				  "SOL/IDER session.\n");
949 			break;
950 		}
951 		/* FALLTHROUGH */
952 	case SIOCGIFMEDIA:
953 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOCxIFMEDIA "
954 			       "(Get/Set Interface Media)");
955 		error = ifmedia_ioctl(ifp, ifr, &adapter->media, command);
956 		break;
957 	case SIOCSIFCAP:
958 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOCSIFCAP (Set Capabilities)");
959 		mask = ifr->ifr_reqcap ^ ifp->if_capenable;
960 		if (mask & IFCAP_HWCSUM) {
961 			ifp->if_capenable ^= IFCAP_HWCSUM;
962 			reinit = 1;
963 		}
964 		if (mask & IFCAP_VLAN_HWTAGGING) {
965 			ifp->if_capenable ^= IFCAP_VLAN_HWTAGGING;
966 			reinit = 1;
967 		}
968 		if (reinit && (ifp->if_flags & IFF_RUNNING)) {
969 			ifp->if_flags &= ~IFF_RUNNING;
970 			em_init(adapter);
971 		}
972 		break;
973 	default:
974 		error = ether_ioctl(ifp, command, data);
975 		break;
976 	}
977 
978 	return (error);
979 }
980 
981 /*********************************************************************
982  *  Watchdog entry point
983  *
984  *  This routine is called whenever hardware quits transmitting.
985  *
986  **********************************************************************/
987 
988 static void
989 em_watchdog(struct ifnet *ifp)
990 {
991 	struct adapter *adapter = ifp->if_softc;
992 
993 	/*
994 	 * If we are in this routine because of pause frames, then
995 	 * don't reset the hardware.
996 	 */
997 	if (E1000_READ_REG(&adapter->hw, STATUS) & E1000_STATUS_TXOFF) {
998 		ifp->if_timer = EM_TX_TIMEOUT;
999 		return;
1000 	}
1001 
1002 	if (em_check_for_link(&adapter->hw) == 0)
1003 		if_printf(ifp, "watchdog timeout -- resetting\n");
1004 
1005 	ifp->if_flags &= ~IFF_RUNNING;
1006 	em_init(adapter);
1007 
1008 	adapter->watchdog_timeouts++;
1009 }
1010 
1011 /*********************************************************************
1012  *  Init entry point
1013  *
1014  *  This routine is used in two ways. It is used by the stack as
1015  *  init entry point in network interface structure. It is also used
1016  *  by the driver as a hw/sw initialization routine to get to a
1017  *  consistent state.
1018  *
1019  *  return 0 on success, positive on failure
1020  **********************************************************************/
1021 
1022 static void
1023 em_init(void *arg)
1024 {
1025 	struct adapter *adapter = arg;
1026 	uint32_t pba;
1027 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1028 
1029 	ASSERT_SERIALIZED(ifp->if_serializer);
1030 
1031 	INIT_DEBUGOUT("em_init: begin");
1032 
1033 	if (ifp->if_flags & IFF_RUNNING)
1034 		return;
1035 
1036 	em_stop(adapter);
1037 
1038 	/*
1039 	 * Packet Buffer Allocation (PBA)
1040 	 * Writing PBA sets the receive portion of the buffer
1041 	 * the remainder is used for the transmit buffer.
1042 	 *
1043 	 * Devices before the 82547 had a Packet Buffer of 64K.
1044 	 *   Default allocation: PBA=48K for Rx, leaving 16K for Tx.
1045 	 * After the 82547 the buffer was reduced to 40K.
1046 	 *   Default allocation: PBA=30K for Rx, leaving 10K for Tx.
1047 	 *   Note: default does not leave enough room for Jumbo Frame >10k.
1048 	 */
1049 	switch (adapter->hw.mac_type) {
1050 	case em_82547:
1051 	case em_82547_rev_2: /* 82547: Total Packet Buffer is 40K */
1052 		if (adapter->hw.max_frame_size > EM_RXBUFFER_8192)
1053 			pba = E1000_PBA_22K; /* 22K for Rx, 18K for Tx */
1054 		else
1055 			pba = E1000_PBA_30K; /* 30K for Rx, 10K for Tx */
1056 
1057 		adapter->tx_fifo_head = 0;
1058 		adapter->tx_head_addr = pba << EM_TX_HEAD_ADDR_SHIFT;
1059 		adapter->tx_fifo_size =
1060 			(E1000_PBA_40K - pba) << EM_PBA_BYTES_SHIFT;
1061 		break;
1062 	/* Total Packet Buffer on these is 48K */
1063 	case em_82571:
1064 	case em_82572:
1065 	case em_80003es2lan:
1066 		pba = E1000_PBA_32K; /* 32K for Rx, 16K for Tx */
1067 		break;
1068 	case em_82573: /* 82573: Total Packet Buffer is 32K */
1069 		pba = E1000_PBA_12K; /* 12K for Rx, 20K for Tx */
1070 		break;
1071 	case em_ich8lan:
1072 		pba = E1000_PBA_8K;
1073 		break;
1074 	case em_ich9lan:
1075 #define E1000_PBA_10K   0x000A
1076 		pba = E1000_PBA_10K;
1077 		break;
1078 	default:
1079 		/* Devices before 82547 had a Packet Buffer of 64K.   */
1080 		if(adapter->hw.max_frame_size > EM_RXBUFFER_8192)
1081 			pba = E1000_PBA_40K; /* 40K for Rx, 24K for Tx */
1082 		else
1083 			pba = E1000_PBA_48K; /* 48K for Rx, 16K for Tx */
1084 	}
1085 
1086 	INIT_DEBUGOUT1("em_init: pba=%dK",pba);
1087 	E1000_WRITE_REG(&adapter->hw, PBA, pba);
1088 
1089 	/* Get the latest mac address, User can use a LAA */
1090 	bcopy(adapter->interface_data.ac_enaddr, adapter->hw.mac_addr,
1091 	      ETHER_ADDR_LEN);
1092 
1093 	/* Initialize the hardware */
1094 	if (em_hardware_init(adapter)) {
1095 		if_printf(ifp, "Unable to initialize the hardware\n");
1096 		return;
1097 	}
1098 	em_update_link_status(adapter);
1099 
1100 	if (ifp->if_capenable & IFCAP_VLAN_HWTAGGING)
1101 		em_enable_vlans(adapter);
1102 
1103 	/* Set hardware offload abilities */
1104 	if (adapter->hw.mac_type >= em_82543) {
1105 		if (ifp->if_capenable & IFCAP_TXCSUM)
1106 			ifp->if_hwassist = EM_CHECKSUM_FEATURES;
1107 		else
1108 			ifp->if_hwassist = 0;
1109 	}
1110 
1111 	/* Prepare transmit descriptors and buffers */
1112 	if (em_setup_transmit_structures(adapter)) {
1113 		if_printf(ifp, "Could not setup transmit structures\n");
1114 		em_stop(adapter);
1115 		return;
1116 	}
1117 	em_initialize_transmit_unit(adapter);
1118 
1119 	/* Setup Multicast table */
1120 	em_set_multi(adapter);
1121 
1122 	/* Prepare receive descriptors and buffers */
1123 	if (em_setup_receive_structures(adapter)) {
1124 		if_printf(ifp, "Could not setup receive structures\n");
1125 		em_stop(adapter);
1126 		return;
1127 	}
1128 	em_initialize_receive_unit(adapter);
1129 
1130 	/* Don't lose promiscuous settings */
1131 	em_set_promisc(adapter);
1132 
1133 	ifp->if_flags |= IFF_RUNNING;
1134 	ifp->if_flags &= ~IFF_OACTIVE;
1135 
1136 	callout_reset(&adapter->timer, hz, em_local_timer, adapter);
1137 	em_clear_hw_cntrs(&adapter->hw);
1138 
1139 #ifdef DEVICE_POLLING
1140 	/* Do not enable interrupt if polling(4) is enabled */
1141 	if (ifp->if_flags & IFF_POLLING)
1142 		em_disable_intr(adapter);
1143 	else
1144 #endif
1145 	em_enable_intr(adapter);
1146 
1147 	/* Don't reset the phy next time init gets called */
1148 	adapter->hw.phy_reset_disable = TRUE;
1149 }
1150 
1151 #ifdef DEVICE_POLLING
1152 
1153 static void
1154 em_poll(struct ifnet *ifp, enum poll_cmd cmd, int count)
1155 {
1156 	struct adapter *adapter = ifp->if_softc;
1157 	uint32_t reg_icr;
1158 
1159 	logif(poll_beg);
1160 
1161 	ASSERT_SERIALIZED(ifp->if_serializer);
1162 
1163 	switch(cmd) {
1164 	case POLL_REGISTER:
1165 		em_disable_intr(adapter);
1166 		break;
1167 	case POLL_DEREGISTER:
1168 		em_enable_intr(adapter);
1169 		break;
1170 	case POLL_AND_CHECK_STATUS:
1171 		reg_icr = E1000_READ_REG(&adapter->hw, ICR);
1172 		if (reg_icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC)) {
1173 			callout_stop(&adapter->timer);
1174 			adapter->hw.get_link_status = 1;
1175 			em_check_for_link(&adapter->hw);
1176 			em_update_link_status(adapter);
1177 			callout_reset(&adapter->timer, hz, em_local_timer,
1178 				      adapter);
1179 		}
1180 		/* fall through */
1181 	case POLL_ONLY:
1182 		if (ifp->if_flags & IFF_RUNNING) {
1183 			em_rxeof(adapter, count);
1184 			em_txeof(adapter);
1185 
1186 			if (!ifq_is_empty(&ifp->if_snd))
1187 				em_start(ifp);
1188 		}
1189 		break;
1190 	}
1191 	logif(poll_end);
1192 }
1193 
1194 #endif /* DEVICE_POLLING */
1195 
1196 /*********************************************************************
1197  *
1198  *  Interrupt Service routine
1199  *
1200  *********************************************************************/
1201 static void
1202 em_intr(void *arg)
1203 {
1204 	uint32_t reg_icr;
1205 	struct ifnet *ifp;
1206 	struct adapter *adapter = arg;
1207 
1208 	ifp = &adapter->interface_data.ac_if;
1209 
1210 	logif(intr_beg);
1211 	ASSERT_SERIALIZED(ifp->if_serializer);
1212 
1213 	reg_icr = E1000_READ_REG(&adapter->hw, ICR);
1214 	if ((adapter->hw.mac_type >= em_82571 &&
1215 	     (reg_icr & E1000_ICR_INT_ASSERTED) == 0) ||
1216 	    reg_icr == 0) {
1217 		logif(intr_end);
1218 		return;
1219 	}
1220 
1221 	/*
1222 	 * XXX: some laptops trigger several spurious interrupts on em(4)
1223 	 * when in the resume cycle. The ICR register reports all-ones
1224 	 * value in this case. Processing such interrupts would lead to
1225 	 * a freeze. I don't know why.
1226 	 */
1227 	if (reg_icr == 0xffffffff) {
1228 		logif(intr_end);
1229 		return;
1230 	}
1231 
1232 	/*
1233 	 * note: do not attempt to improve efficiency by looping.  This
1234 	 * only results in unnecessary piecemeal collection of received
1235 	 * packets and unnecessary piecemeal cleanups of the transmit ring.
1236 	 */
1237 	if (ifp->if_flags & IFF_RUNNING) {
1238 		em_rxeof(adapter, -1);
1239 		em_txeof(adapter);
1240 	}
1241 
1242 	/* Link status change */
1243 	if (reg_icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC)) {
1244 		callout_stop(&adapter->timer);
1245 		adapter->hw.get_link_status = 1;
1246 		em_check_for_link(&adapter->hw);
1247 		em_update_link_status(adapter);
1248 		callout_reset(&adapter->timer, hz, em_local_timer, adapter);
1249 	}
1250 
1251 	if (reg_icr & E1000_ICR_RXO)
1252 		adapter->rx_overruns++;
1253 
1254 	if ((ifp->if_flags & IFF_RUNNING) && !ifq_is_empty(&ifp->if_snd))
1255 		em_start(ifp);
1256 	logif(intr_end);
1257 }
1258 
1259 /*********************************************************************
1260  *
1261  *  Media Ioctl callback
1262  *
1263  *  This routine is called whenever the user queries the status of
1264  *  the interface using ifconfig.
1265  *
1266  **********************************************************************/
1267 static void
1268 em_media_status(struct ifnet *ifp, struct ifmediareq *ifmr)
1269 {
1270 	struct adapter *adapter = ifp->if_softc;
1271 	u_char fiber_type = IFM_1000_SX;
1272 
1273 	INIT_DEBUGOUT("em_media_status: begin");
1274 
1275 	ASSERT_SERIALIZED(ifp->if_serializer);
1276 
1277 	em_check_for_link(&adapter->hw);
1278 	em_update_link_status(adapter);
1279 
1280 	ifmr->ifm_status = IFM_AVALID;
1281 	ifmr->ifm_active = IFM_ETHER;
1282 
1283 	if (!adapter->link_active)
1284 		return;
1285 
1286 	ifmr->ifm_status |= IFM_ACTIVE;
1287 
1288 	if (adapter->hw.media_type == em_media_type_fiber ||
1289 	    adapter->hw.media_type == em_media_type_internal_serdes) {
1290 		if (adapter->hw.mac_type == em_82545)
1291 			fiber_type = IFM_1000_LX;
1292 		ifmr->ifm_active |= fiber_type | IFM_FDX;
1293 	} else {
1294 		switch (adapter->link_speed) {
1295 		case 10:
1296 			ifmr->ifm_active |= IFM_10_T;
1297 			break;
1298 		case 100:
1299 			ifmr->ifm_active |= IFM_100_TX;
1300 			break;
1301 		case 1000:
1302 			ifmr->ifm_active |= IFM_1000_T;
1303 			break;
1304 		}
1305 		if (adapter->link_duplex == FULL_DUPLEX)
1306 			ifmr->ifm_active |= IFM_FDX;
1307 		else
1308 			ifmr->ifm_active |= IFM_HDX;
1309 	}
1310 }
1311 
1312 /*********************************************************************
1313  *
1314  *  Media Ioctl callback
1315  *
1316  *  This routine is called when the user changes speed/duplex using
1317  *  media/mediopt option with ifconfig.
1318  *
1319  **********************************************************************/
1320 static int
1321 em_media_change(struct ifnet *ifp)
1322 {
1323 	struct adapter *adapter = ifp->if_softc;
1324 	struct ifmedia *ifm = &adapter->media;
1325 
1326 	INIT_DEBUGOUT("em_media_change: begin");
1327 
1328 	ASSERT_SERIALIZED(ifp->if_serializer);
1329 
1330 	if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER)
1331 		return (EINVAL);
1332 
1333 	switch (IFM_SUBTYPE(ifm->ifm_media)) {
1334 	case IFM_AUTO:
1335 		adapter->hw.autoneg = DO_AUTO_NEG;
1336 		adapter->hw.autoneg_advertised = AUTONEG_ADV_DEFAULT;
1337 		break;
1338 	case IFM_1000_LX:
1339 	case IFM_1000_SX:
1340 	case IFM_1000_T:
1341 		adapter->hw.autoneg = DO_AUTO_NEG;
1342 		adapter->hw.autoneg_advertised = ADVERTISE_1000_FULL;
1343 		break;
1344 	case IFM_100_TX:
1345 		adapter->hw.autoneg = FALSE;
1346 		adapter->hw.autoneg_advertised = 0;
1347 		if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
1348 			adapter->hw.forced_speed_duplex = em_100_full;
1349 		else
1350 			adapter->hw.forced_speed_duplex = em_100_half;
1351 		break;
1352 	case IFM_10_T:
1353 		adapter->hw.autoneg = FALSE;
1354 		adapter->hw.autoneg_advertised = 0;
1355 		if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
1356 			adapter->hw.forced_speed_duplex = em_10_full;
1357 		else
1358 			adapter->hw.forced_speed_duplex = em_10_half;
1359 		break;
1360 	default:
1361 		if_printf(ifp, "Unsupported media type\n");
1362 	}
1363 	/*
1364 	 * As the speed/duplex settings may have changed we need to
1365 	 * reset the PHY.
1366 	 */
1367 	adapter->hw.phy_reset_disable = FALSE;
1368 
1369 	ifp->if_flags &= ~IFF_RUNNING;
1370 	em_init(adapter);
1371 
1372 	return(0);
1373 }
1374 
1375 static void
1376 em_tx_cb(void *arg, bus_dma_segment_t *seg, int nsegs, bus_size_t mapsize,
1377 	 int error)
1378 {
1379 	struct em_q *q = arg;
1380 
1381 	if (error)
1382 		return;
1383 	KASSERT(nsegs <= EM_MAX_SCATTER,
1384 		("Too many DMA segments returned when mapping tx packet"));
1385 	q->nsegs = nsegs;
1386 	bcopy(seg, q->segs, nsegs * sizeof(seg[0]));
1387 }
1388 
1389 /*********************************************************************
1390  *
1391  *  This routine maps the mbufs to tx descriptors.
1392  *
1393  *  return 0 on success, positive on failure
1394  **********************************************************************/
1395 static int
1396 em_encap(struct adapter *adapter, struct mbuf *m_head)
1397 {
1398 	uint32_t txd_upper = 0, txd_lower = 0, txd_used = 0, txd_saved = 0;
1399 	int i, j, error, last = 0;
1400 
1401 	struct em_q q;
1402 	struct em_buffer *tx_buffer = NULL, *tx_buffer_first;
1403 	bus_dmamap_t map;
1404 	struct em_tx_desc *current_tx_desc = NULL;
1405 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1406 
1407 	/*
1408 	 * Force a cleanup if number of TX descriptors
1409 	 * available hits the threshold
1410 	 */
1411 	if (adapter->num_tx_desc_avail <= EM_TX_CLEANUP_THRESHOLD) {
1412 		em_txeof(adapter);
1413 		if (adapter->num_tx_desc_avail <= EM_TX_CLEANUP_THRESHOLD) {
1414 			adapter->no_tx_desc_avail1++;
1415 			return (ENOBUFS);
1416 		}
1417 	}
1418 
1419 	/*
1420 	 * Capture the first descriptor index, this descriptor will have
1421 	 * the index of the EOP which is the only one that now gets a
1422 	 * DONE bit writeback.
1423 	 */
1424 	tx_buffer_first = &adapter->tx_buffer_area[adapter->next_avail_tx_desc];
1425 
1426 	/*
1427 	 * Map the packet for DMA.
1428 	 */
1429 	map = tx_buffer_first->map;
1430 	error = bus_dmamap_load_mbuf(adapter->txtag, map, m_head, em_tx_cb,
1431 				     &q, BUS_DMA_NOWAIT);
1432 	if (error != 0) {
1433 		adapter->no_tx_dma_setup++;
1434 		return (error);
1435 	}
1436 	KASSERT(q.nsegs != 0, ("em_encap: empty packet"));
1437 
1438 	if (q.nsegs > (adapter->num_tx_desc_avail - 2)) {
1439 		adapter->no_tx_desc_avail2++;
1440 		error = ENOBUFS;
1441 		goto fail;
1442 	}
1443 
1444 	if (ifp->if_hwassist > 0) {
1445 		em_transmit_checksum_setup(adapter,  m_head,
1446 					   &txd_upper, &txd_lower);
1447 	}
1448 
1449 	i = adapter->next_avail_tx_desc;
1450 	if (adapter->pcix_82544)
1451 		txd_saved = i;
1452 
1453 	/* Set up our transmit descriptors */
1454 	for (j = 0; j < q.nsegs; j++) {
1455 		/* If adapter is 82544 and on PCIX bus */
1456 		if(adapter->pcix_82544) {
1457 			DESC_ARRAY desc_array;
1458 			uint32_t array_elements, counter;
1459 
1460 			/*
1461 			 * Check the Address and Length combination and
1462 			 * split the data accordingly
1463 			 */
1464 			array_elements = em_fill_descriptors(q.segs[j].ds_addr,
1465 						q.segs[j].ds_len, &desc_array);
1466 			for (counter = 0; counter < array_elements; counter++) {
1467 				if (txd_used == adapter->num_tx_desc_avail) {
1468 					adapter->next_avail_tx_desc = txd_saved;
1469 					adapter->no_tx_desc_avail2++;
1470 					error = ENOBUFS;
1471 					goto fail;
1472 				}
1473 				tx_buffer = &adapter->tx_buffer_area[i];
1474 				current_tx_desc = &adapter->tx_desc_base[i];
1475 				current_tx_desc->buffer_addr = htole64(
1476 					desc_array.descriptor[counter].address);
1477 				current_tx_desc->lower.data = htole32(
1478 					adapter->txd_cmd | txd_lower |
1479 					(uint16_t)desc_array.descriptor[counter].length);
1480 				current_tx_desc->upper.data = htole32(txd_upper);
1481 
1482 				last = i;
1483 				if (++i == adapter->num_tx_desc)
1484 					i = 0;
1485 
1486 				tx_buffer->m_head = NULL;
1487 				tx_buffer->next_eop = -1;
1488 				txd_used++;
1489 			}
1490 		} else {
1491 			tx_buffer = &adapter->tx_buffer_area[i];
1492 			current_tx_desc = &adapter->tx_desc_base[i];
1493 
1494 			current_tx_desc->buffer_addr = htole64(q.segs[j].ds_addr);
1495 			current_tx_desc->lower.data = htole32(
1496 				adapter->txd_cmd | txd_lower | q.segs[j].ds_len);
1497 			current_tx_desc->upper.data = htole32(txd_upper);
1498 
1499 			last = i;
1500 			if (++i == adapter->num_tx_desc)
1501 				i = 0;
1502 
1503 			tx_buffer->m_head = NULL;
1504 			tx_buffer->next_eop = -1;
1505 		}
1506 	}
1507 
1508 	adapter->next_avail_tx_desc = i;
1509 	if (adapter->pcix_82544)
1510 		adapter->num_tx_desc_avail -= txd_used;
1511 	else
1512 		adapter->num_tx_desc_avail -= q.nsegs;
1513 
1514 	/* Find out if we are in vlan mode */
1515 	if (m_head->m_flags & M_VLANTAG) {
1516 		/* Set the vlan id */
1517 		current_tx_desc->upper.fields.special =
1518 			htole16(m_head->m_pkthdr.ether_vlantag);
1519 
1520 		/* Tell hardware to add tag */
1521 		current_tx_desc->lower.data |= htole32(E1000_TXD_CMD_VLE);
1522 	}
1523 
1524 	tx_buffer->m_head = m_head;
1525 	tx_buffer_first->map = tx_buffer->map;
1526 	tx_buffer->map = map;
1527 	bus_dmamap_sync(adapter->txtag, map, BUS_DMASYNC_PREWRITE);
1528 
1529 	/*
1530 	 * Last Descriptor of Packet needs End Of Packet (EOP)
1531 	 * and Report Status (RS)
1532 	 */
1533 	current_tx_desc->lower.data |=
1534 		htole32(E1000_TXD_CMD_EOP | E1000_TXD_CMD_RS);
1535 
1536 	/*
1537 	 * Keep track in the first buffer which descriptor will be
1538 	 * written back.
1539 	 */
1540 	tx_buffer_first->next_eop = last;
1541 
1542 	bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
1543 			BUS_DMASYNC_PREWRITE);
1544 
1545 	/*
1546 	 * Advance the Transmit Descriptor Tail (Tdt), this tells the E1000
1547 	 * that this frame is available to transmit.
1548 	 */
1549 	if (adapter->hw.mac_type == em_82547 &&
1550 	    adapter->link_duplex == HALF_DUPLEX) {
1551 		em_82547_move_tail_serialized(adapter);
1552 	} else {
1553 		E1000_WRITE_REG(&adapter->hw, TDT, i);
1554 		if (adapter->hw.mac_type == em_82547) {
1555 			em_82547_update_fifo_head(adapter,
1556 						  m_head->m_pkthdr.len);
1557 		}
1558 	}
1559 
1560 	return (0);
1561 fail:
1562 	bus_dmamap_unload(adapter->txtag, map);
1563 	return error;
1564 }
1565 
1566 /*********************************************************************
1567  *
1568  * 82547 workaround to avoid controller hang in half-duplex environment.
1569  * The workaround is to avoid queuing a large packet that would span
1570  * the internal Tx FIFO ring boundary. We need to reset the FIFO pointers
1571  * in this case. We do that only when FIFO is quiescent.
1572  *
1573  **********************************************************************/
1574 static void
1575 em_82547_move_tail(void *arg)
1576 {
1577 	struct adapter *adapter = arg;
1578 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1579 
1580 	lwkt_serialize_enter(ifp->if_serializer);
1581 	em_82547_move_tail_serialized(adapter);
1582 	lwkt_serialize_exit(ifp->if_serializer);
1583 }
1584 
1585 static void
1586 em_82547_move_tail_serialized(struct adapter *adapter)
1587 {
1588 	uint16_t hw_tdt;
1589 	uint16_t sw_tdt;
1590 	struct em_tx_desc *tx_desc;
1591 	uint16_t length = 0;
1592 	boolean_t eop = 0;
1593 
1594 	hw_tdt = E1000_READ_REG(&adapter->hw, TDT);
1595 	sw_tdt = adapter->next_avail_tx_desc;
1596 
1597 	while (hw_tdt != sw_tdt) {
1598 		tx_desc = &adapter->tx_desc_base[hw_tdt];
1599 		length += tx_desc->lower.flags.length;
1600 		eop = tx_desc->lower.data & E1000_TXD_CMD_EOP;
1601 		if (++hw_tdt == adapter->num_tx_desc)
1602 			hw_tdt = 0;
1603 
1604 		if (eop) {
1605 			if (em_82547_fifo_workaround(adapter, length)) {
1606 				adapter->tx_fifo_wrk_cnt++;
1607 				callout_reset(&adapter->tx_fifo_timer, 1,
1608 					em_82547_move_tail, adapter);
1609 				break;
1610 			}
1611 			E1000_WRITE_REG(&adapter->hw, TDT, hw_tdt);
1612 			em_82547_update_fifo_head(adapter, length);
1613 			length = 0;
1614 		}
1615 	}
1616 }
1617 
1618 static int
1619 em_82547_fifo_workaround(struct adapter *adapter, int len)
1620 {
1621 	int fifo_space, fifo_pkt_len;
1622 
1623 	fifo_pkt_len = roundup2(len + EM_FIFO_HDR, EM_FIFO_HDR);
1624 
1625 	if (adapter->link_duplex == HALF_DUPLEX) {
1626 		fifo_space = adapter->tx_fifo_size - adapter->tx_fifo_head;
1627 
1628 		if (fifo_pkt_len >= (EM_82547_PKT_THRESH + fifo_space)) {
1629 			if (em_82547_tx_fifo_reset(adapter))
1630 				return (0);
1631 			else
1632 				return (1);
1633 		}
1634 	}
1635 
1636 	return (0);
1637 }
1638 
1639 static void
1640 em_82547_update_fifo_head(struct adapter *adapter, int len)
1641 {
1642 	int fifo_pkt_len = roundup2(len + EM_FIFO_HDR, EM_FIFO_HDR);
1643 
1644 	/* tx_fifo_head is always 16 byte aligned */
1645 	adapter->tx_fifo_head += fifo_pkt_len;
1646 	if (adapter->tx_fifo_head >= adapter->tx_fifo_size)
1647 		adapter->tx_fifo_head -= adapter->tx_fifo_size;
1648 }
1649 
1650 static int
1651 em_82547_tx_fifo_reset(struct adapter *adapter)
1652 {
1653 	uint32_t tctl;
1654 
1655 	if (E1000_READ_REG(&adapter->hw, TDT) == E1000_READ_REG(&adapter->hw, TDH) &&
1656 	    E1000_READ_REG(&adapter->hw, TDFT) == E1000_READ_REG(&adapter->hw, TDFH) &&
1657 	    E1000_READ_REG(&adapter->hw, TDFTS) == E1000_READ_REG(&adapter->hw, TDFHS) &&
1658 	    E1000_READ_REG(&adapter->hw, TDFPC) == 0) {
1659 		/* Disable TX unit */
1660 		tctl = E1000_READ_REG(&adapter->hw, TCTL);
1661 		E1000_WRITE_REG(&adapter->hw, TCTL, tctl & ~E1000_TCTL_EN);
1662 
1663 		/* Reset FIFO pointers */
1664 		E1000_WRITE_REG(&adapter->hw, TDFT,  adapter->tx_head_addr);
1665 		E1000_WRITE_REG(&adapter->hw, TDFH,  adapter->tx_head_addr);
1666 		E1000_WRITE_REG(&adapter->hw, TDFTS, adapter->tx_head_addr);
1667 		E1000_WRITE_REG(&adapter->hw, TDFHS, adapter->tx_head_addr);
1668 
1669 		/* Re-enable TX unit */
1670 		E1000_WRITE_REG(&adapter->hw, TCTL, tctl);
1671 		E1000_WRITE_FLUSH(&adapter->hw);
1672 
1673 		adapter->tx_fifo_head = 0;
1674 		adapter->tx_fifo_reset_cnt++;
1675 
1676 		return (TRUE);
1677 	} else {
1678 		return (FALSE);
1679 	}
1680 }
1681 
1682 static void
1683 em_set_promisc(struct adapter *adapter)
1684 {
1685 	uint32_t reg_rctl;
1686 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1687 
1688 	reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1689 
1690 	adapter->em_insert_vlan_header = 0;
1691 	if (ifp->if_flags & IFF_PROMISC) {
1692 		reg_rctl |= (E1000_RCTL_UPE | E1000_RCTL_MPE);
1693 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1694 
1695 		/*
1696 		 * Disable VLAN stripping in promiscous mode.
1697 		 * This enables bridging of vlan tagged frames to occur
1698 		 * and also allows vlan tags to be seen in tcpdump.
1699 		 */
1700 		if (ifp->if_capenable & IFCAP_VLAN_HWTAGGING)
1701 			em_disable_vlans(adapter);
1702 		adapter->em_insert_vlan_header = 1;
1703 	} else if (ifp->if_flags & IFF_ALLMULTI) {
1704 		reg_rctl |= E1000_RCTL_MPE;
1705 		reg_rctl &= ~E1000_RCTL_UPE;
1706 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1707 	}
1708 }
1709 
1710 static void
1711 em_disable_promisc(struct adapter *adapter)
1712 {
1713 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1714 
1715 	uint32_t reg_rctl;
1716 
1717 	reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1718 
1719 	reg_rctl &= (~E1000_RCTL_UPE);
1720 	reg_rctl &= (~E1000_RCTL_MPE);
1721 	E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1722 
1723 	if (ifp->if_capenable & IFCAP_VLAN_HWTAGGING)
1724 		em_enable_vlans(adapter);
1725 	adapter->em_insert_vlan_header = 0;
1726 }
1727 
1728 /*********************************************************************
1729  *  Multicast Update
1730  *
1731  *  This routine is called whenever multicast address list is updated.
1732  *
1733  **********************************************************************/
1734 
1735 static void
1736 em_set_multi(struct adapter *adapter)
1737 {
1738 	uint32_t reg_rctl = 0;
1739 	uint8_t mta[MAX_NUM_MULTICAST_ADDRESSES * ETH_LENGTH_OF_ADDRESS];
1740 	struct ifmultiaddr *ifma;
1741 	int mcnt = 0;
1742 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1743 
1744 	IOCTL_DEBUGOUT("em_set_multi: begin");
1745 
1746 	if (adapter->hw.mac_type == em_82542_rev2_0) {
1747 		reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1748 		if (adapter->hw.pci_cmd_word & CMD_MEM_WRT_INVALIDATE)
1749 			em_pci_clear_mwi(&adapter->hw);
1750 		reg_rctl |= E1000_RCTL_RST;
1751 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1752 		msec_delay(5);
1753 	}
1754 
1755 	LIST_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
1756 		if (ifma->ifma_addr->sa_family != AF_LINK)
1757 			continue;
1758 
1759 		if (mcnt == MAX_NUM_MULTICAST_ADDRESSES)
1760 			break;
1761 
1762 		bcopy(LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
1763 		      &mta[mcnt*ETH_LENGTH_OF_ADDRESS], ETH_LENGTH_OF_ADDRESS);
1764 		mcnt++;
1765 	}
1766 
1767 	if (mcnt >= MAX_NUM_MULTICAST_ADDRESSES) {
1768 		reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1769 		reg_rctl |= E1000_RCTL_MPE;
1770 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1771 	} else {
1772 		em_mc_addr_list_update(&adapter->hw, mta, mcnt, 0, 1);
1773 	}
1774 
1775 	if (adapter->hw.mac_type == em_82542_rev2_0) {
1776 		reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1777 		reg_rctl &= ~E1000_RCTL_RST;
1778 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1779 		msec_delay(5);
1780 		if (adapter->hw.pci_cmd_word & CMD_MEM_WRT_INVALIDATE)
1781                         em_pci_set_mwi(&adapter->hw);
1782 	}
1783 }
1784 
1785 /*********************************************************************
1786  *  Timer routine
1787  *
1788  *  This routine checks for link status and updates statistics.
1789  *
1790  **********************************************************************/
1791 
1792 static void
1793 em_local_timer(void *arg)
1794 {
1795 	struct ifnet *ifp;
1796 	struct adapter *adapter = arg;
1797 	ifp = &adapter->interface_data.ac_if;
1798 
1799 	lwkt_serialize_enter(ifp->if_serializer);
1800 
1801 	em_check_for_link(&adapter->hw);
1802 	em_update_link_status(adapter);
1803 	em_update_stats_counters(adapter);
1804 	if (em_display_debug_stats && ifp->if_flags & IFF_RUNNING)
1805 		em_print_hw_stats(adapter);
1806 	em_smartspeed(adapter);
1807 
1808 	callout_reset(&adapter->timer, hz, em_local_timer, adapter);
1809 
1810 	lwkt_serialize_exit(ifp->if_serializer);
1811 }
1812 
1813 static void
1814 em_update_link_status(struct adapter *adapter)
1815 {
1816 	struct ifnet *ifp;
1817 	ifp = &adapter->interface_data.ac_if;
1818 
1819 	if (E1000_READ_REG(&adapter->hw, STATUS) & E1000_STATUS_LU) {
1820 		if (adapter->link_active == 0) {
1821 			em_get_speed_and_duplex(&adapter->hw,
1822 						&adapter->link_speed,
1823 						&adapter->link_duplex);
1824 			/* Check if we may set SPEED_MODE bit on PCI-E */
1825 			if (adapter->link_speed == SPEED_1000 &&
1826 			    (adapter->hw.mac_type == em_82571 ||
1827 			     adapter->hw.mac_type == em_82572)) {
1828 				int tarc0;
1829 
1830 				tarc0 = E1000_READ_REG(&adapter->hw, TARC0);
1831 				tarc0 |= SPEED_MODE_BIT;
1832 				E1000_WRITE_REG(&adapter->hw, TARC0, tarc0);
1833 			}
1834 			if (bootverbose) {
1835 				if_printf(&adapter->interface_data.ac_if,
1836 					  "Link is up %d Mbps %s\n",
1837 					  adapter->link_speed,
1838 					  adapter->link_duplex == FULL_DUPLEX ?
1839 						"Full Duplex" : "Half Duplex");
1840 			}
1841 			adapter->link_active = 1;
1842 			adapter->smartspeed = 0;
1843 			ifp->if_baudrate = adapter->link_speed * 1000000;
1844 			ifp->if_link_state = LINK_STATE_UP;
1845 			if_link_state_change(ifp);
1846 		}
1847 	} else {
1848 		if (adapter->link_active == 1) {
1849 			ifp->if_baudrate = 0;
1850 			adapter->link_speed = 0;
1851 			adapter->link_duplex = 0;
1852 			if (bootverbose) {
1853 				if_printf(&adapter->interface_data.ac_if,
1854 					  "Link is Down\n");
1855 			}
1856 			adapter->link_active = 0;
1857 			ifp->if_link_state = LINK_STATE_DOWN;
1858 			if_link_state_change(ifp);
1859 		}
1860 	}
1861 }
1862 
1863 /*********************************************************************
1864  *
1865  *  This routine disables all traffic on the adapter by issuing a
1866  *  global reset on the MAC and deallocates TX/RX buffers.
1867  *
1868  **********************************************************************/
1869 
1870 static void
1871 em_stop(void *arg)
1872 {
1873 	struct ifnet   *ifp;
1874 	struct adapter * adapter = arg;
1875 	ifp = &adapter->interface_data.ac_if;
1876 
1877 	ASSERT_SERIALIZED(ifp->if_serializer);
1878 
1879 	INIT_DEBUGOUT("em_stop: begin");
1880 	em_disable_intr(adapter);
1881 	em_reset_hw(&adapter->hw);
1882 	callout_stop(&adapter->timer);
1883 	callout_stop(&adapter->tx_fifo_timer);
1884 	em_free_transmit_structures(adapter);
1885 	em_free_receive_structures(adapter);
1886 
1887 	/* Tell the stack that the interface is no longer active */
1888 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
1889 	ifp->if_timer = 0;
1890 }
1891 
1892 /*********************************************************************
1893  *
1894  *  Determine hardware revision.
1895  *
1896  **********************************************************************/
1897 static void
1898 em_identify_hardware(struct adapter *adapter)
1899 {
1900 	device_t dev = adapter->dev;
1901 
1902 	/* Make sure our PCI config space has the necessary stuff set */
1903 	adapter->hw.pci_cmd_word = pci_read_config(dev, PCIR_COMMAND, 2);
1904 	if (!((adapter->hw.pci_cmd_word & PCIM_CMD_BUSMASTEREN) &&
1905 	      (adapter->hw.pci_cmd_word & PCIM_CMD_MEMEN))) {
1906 		device_printf(dev, "Memory Access and/or Bus Master bits "
1907 			      "were not set!\n");
1908 		adapter->hw.pci_cmd_word |= PCIM_CMD_BUSMASTEREN |
1909 					    PCIM_CMD_MEMEN;
1910 		pci_write_config(dev, PCIR_COMMAND,
1911 				 adapter->hw.pci_cmd_word, 2);
1912 	}
1913 
1914 	/* Save off the information about this board */
1915 	adapter->hw.vendor_id = pci_get_vendor(dev);
1916 	adapter->hw.device_id = pci_get_device(dev);
1917 	adapter->hw.revision_id = pci_get_revid(dev);
1918 	adapter->hw.subsystem_vendor_id = pci_get_subvendor(dev);
1919 	adapter->hw.subsystem_id = pci_get_subdevice(dev);
1920 
1921 	/* Identify the MAC */
1922 	if (em_set_mac_type(&adapter->hw))
1923 		device_printf(dev, "Unknown MAC Type\n");
1924 
1925 	if (adapter->hw.mac_type == em_82541 ||
1926 	    adapter->hw.mac_type == em_82541_rev_2 ||
1927 	    adapter->hw.mac_type == em_82547 ||
1928 	    adapter->hw.mac_type == em_82547_rev_2)
1929 		adapter->hw.phy_init_script = TRUE;
1930 }
1931 
1932 static int
1933 em_allocate_pci_resources(device_t dev)
1934 {
1935 	struct adapter *adapter = device_get_softc(dev);
1936 	int rid;
1937 
1938 	rid = PCIR_BAR(0);
1939 	adapter->res_memory = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
1940 						     &rid, RF_ACTIVE);
1941 	if (adapter->res_memory == NULL) {
1942 		device_printf(dev, "Unable to allocate bus resource: memory\n");
1943 		return ENXIO;
1944 	}
1945 	adapter->osdep.mem_bus_space_tag =
1946 		rman_get_bustag(adapter->res_memory);
1947 	adapter->osdep.mem_bus_space_handle =
1948 	    rman_get_bushandle(adapter->res_memory);
1949 	adapter->hw.hw_addr = (uint8_t *)&adapter->osdep.mem_bus_space_handle;
1950 
1951 	if (adapter->hw.mac_type > em_82543) {
1952 		/* Figure our where our IO BAR is ? */
1953 		for (rid = PCIR_BAR(0); rid < PCIR_CIS;) {
1954 			uint32_t val;
1955 
1956 			val = pci_read_config(dev, rid, 4);
1957 			if (EM_BAR_TYPE(val) == EM_BAR_TYPE_IO) {
1958 				adapter->io_rid = rid;
1959 				break;
1960 			}
1961 			rid += 4;
1962 			/* check for 64bit BAR */
1963 			if (EM_BAR_MEM_TYPE(val) == EM_BAR_MEM_TYPE_64BIT)
1964 				rid += 4;
1965 		}
1966 		if (rid >= PCIR_CIS) {
1967 			device_printf(dev, "Unable to locate IO BAR\n");
1968 			return (ENXIO);
1969  		}
1970 
1971 		adapter->res_ioport = bus_alloc_resource_any(dev,
1972 		    SYS_RES_IOPORT, &adapter->io_rid, RF_ACTIVE);
1973 		if (!(adapter->res_ioport)) {
1974 			device_printf(dev, "Unable to allocate bus resource: "
1975 				      "ioport\n");
1976 			return ENXIO;
1977 		}
1978 		adapter->hw.io_base = 0;
1979 		adapter->osdep.io_bus_space_tag =
1980 			rman_get_bustag(adapter->res_ioport);
1981 		adapter->osdep.io_bus_space_handle =
1982 			rman_get_bushandle(adapter->res_ioport);
1983 	}
1984 
1985 	/* For ICH8 we need to find the flash memory. */
1986 	if ((adapter->hw.mac_type == em_ich8lan) ||
1987 	    (adapter->hw.mac_type == em_ich9lan)) {
1988 		rid = EM_FLASH;
1989 		adapter->flash_mem = bus_alloc_resource_any(dev,
1990 		    SYS_RES_MEMORY, &rid, RF_ACTIVE);
1991 		if (adapter->flash_mem == NULL) {
1992 			device_printf(dev, "Unable to allocate bus resource: "
1993 				      "flash memory\n");
1994 			return ENXIO;
1995 		}
1996 		adapter->osdep.flash_bus_space_tag =
1997 		    rman_get_bustag(adapter->flash_mem);
1998 		adapter->osdep.flash_bus_space_handle =
1999 		    rman_get_bushandle(adapter->flash_mem);
2000 	}
2001 
2002 	rid = 0x0;
2003 	adapter->res_interrupt = bus_alloc_resource_any(dev, SYS_RES_IRQ,
2004 	    &rid, RF_SHAREABLE | RF_ACTIVE);
2005 	if (adapter->res_interrupt == NULL) {
2006 		device_printf(dev, "Unable to allocate bus resource: "
2007 			      "interrupt\n");
2008 		return ENXIO;
2009 	}
2010 
2011 	adapter->hw.back = &adapter->osdep;
2012 
2013 	return 0;
2014 }
2015 
2016 static void
2017 em_free_pci_resources(device_t dev)
2018 {
2019 	struct adapter *adapter = device_get_softc(dev);
2020 
2021 	if (adapter->res_interrupt != NULL) {
2022 		bus_release_resource(dev, SYS_RES_IRQ, 0,
2023 				     adapter->res_interrupt);
2024 	}
2025 	if (adapter->res_memory != NULL) {
2026 		bus_release_resource(dev, SYS_RES_MEMORY, PCIR_BAR(0),
2027 				     adapter->res_memory);
2028 	}
2029 
2030 	if (adapter->res_ioport != NULL) {
2031 		bus_release_resource(dev, SYS_RES_IOPORT, adapter->io_rid,
2032 				     adapter->res_ioport);
2033 	}
2034 
2035 	if (adapter->flash_mem != NULL) {
2036 		bus_release_resource(dev, SYS_RES_MEMORY, EM_FLASH,
2037 				     adapter->flash_mem);
2038 	}
2039 }
2040 
2041 /*********************************************************************
2042  *
2043  *  Initialize the hardware to a configuration as specified by the
2044  *  adapter structure. The controller is reset, the EEPROM is
2045  *  verified, the MAC address is set, then the shared initialization
2046  *  routines are called.
2047  *
2048  **********************************************************************/
2049 static int
2050 em_hardware_init(struct adapter *adapter)
2051 {
2052 	uint16_t	rx_buffer_size;
2053 
2054 	INIT_DEBUGOUT("em_hardware_init: begin");
2055 	/* Issue a global reset */
2056 	em_reset_hw(&adapter->hw);
2057 
2058 	/* When hardware is reset, fifo_head is also reset */
2059 	adapter->tx_fifo_head = 0;
2060 
2061 	/* Make sure we have a good EEPROM before we read from it */
2062 	if (em_validate_eeprom_checksum(&adapter->hw) < 0) {
2063 		if (em_validate_eeprom_checksum(&adapter->hw) < 0) {
2064 			device_printf(adapter->dev,
2065 				      "The EEPROM Checksum Is Not Valid\n");
2066 			return (EIO);
2067 		}
2068 	}
2069 
2070 	if (em_read_part_num(&adapter->hw, &(adapter->part_num)) < 0) {
2071 		device_printf(adapter->dev,
2072 			      "EEPROM read error while reading part number\n");
2073 		return (EIO);
2074 	}
2075 
2076 	/* Set up smart power down as default off on newer adapters. */
2077 	if (!em_smart_pwr_down &&
2078 	    (adapter->hw.mac_type == em_82571 ||
2079 	     adapter->hw.mac_type == em_82572)) {
2080 		uint16_t phy_tmp = 0;
2081 
2082 		/* Speed up time to link by disabling smart power down. */
2083 		em_read_phy_reg(&adapter->hw, IGP02E1000_PHY_POWER_MGMT,
2084 				&phy_tmp);
2085 		phy_tmp &= ~IGP02E1000_PM_SPD;
2086 		em_write_phy_reg(&adapter->hw, IGP02E1000_PHY_POWER_MGMT,
2087 				 phy_tmp);
2088 	}
2089 
2090 	/*
2091 	 * These parameters control the automatic generation (Tx) and
2092 	 * response (Rx) to Ethernet PAUSE frames.
2093 	 * - High water mark should allow for at least two frames to be
2094 	 *   received after sending an XOFF.
2095 	 * - Low water mark works best when it is very near the high water mark.
2096 	 *   This allows the receiver to restart by sending XON when it has
2097 	 *   drained a bit.  Here we use an arbitary value of 1500 which will
2098 	 *   restart after one full frame is pulled from the buffer.  There
2099 	 *   could be several smaller frames in the buffer and if so they will
2100 	 *   not trigger the XON until their total number reduces the buffer
2101 	 *   by 1500.
2102 	 * - The pause time is fairly large at 1000 x 512ns = 512 usec.
2103 	 */
2104 	rx_buffer_size = ((E1000_READ_REG(&adapter->hw, PBA) & 0xffff) << 10);
2105 
2106 	adapter->hw.fc_high_water =
2107 	    rx_buffer_size - roundup2(adapter->hw.max_frame_size, 1024);
2108 	adapter->hw.fc_low_water = adapter->hw.fc_high_water - 1500;
2109 	if (adapter->hw.mac_type == em_80003es2lan)
2110 		adapter->hw.fc_pause_time = 0xFFFF;
2111 	else
2112 		adapter->hw.fc_pause_time = 1000;
2113 	adapter->hw.fc_send_xon = TRUE;
2114 	adapter->hw.fc = E1000_FC_FULL;
2115 
2116 	if (em_init_hw(&adapter->hw) < 0) {
2117 		device_printf(adapter->dev, "Hardware Initialization Failed");
2118 		return (EIO);
2119 	}
2120 
2121 	em_check_for_link(&adapter->hw);
2122 
2123 	return (0);
2124 }
2125 
2126 /*********************************************************************
2127  *
2128  *  Setup networking device structure and register an interface.
2129  *
2130  **********************************************************************/
2131 static void
2132 em_setup_interface(device_t dev, struct adapter *adapter)
2133 {
2134 	struct ifnet *ifp;
2135 	u_char fiber_type = IFM_1000_SX;	/* default type */
2136 	INIT_DEBUGOUT("em_setup_interface: begin");
2137 
2138 	ifp = &adapter->interface_data.ac_if;
2139 	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
2140 	ifp->if_mtu = ETHERMTU;
2141 	ifp->if_baudrate = 1000000000;
2142 	ifp->if_init =  em_init;
2143 	ifp->if_softc = adapter;
2144 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
2145 	ifp->if_ioctl = em_ioctl;
2146 	ifp->if_start = em_start;
2147 #ifdef DEVICE_POLLING
2148 	ifp->if_poll = em_poll;
2149 #endif
2150 	ifp->if_watchdog = em_watchdog;
2151 	ifq_set_maxlen(&ifp->if_snd, adapter->num_tx_desc - 1);
2152 	ifq_set_ready(&ifp->if_snd);
2153 
2154 	if (adapter->hw.mac_type >= em_82543)
2155 		ifp->if_capabilities |= IFCAP_HWCSUM;
2156 
2157 	ifp->if_capenable = ifp->if_capabilities;
2158 
2159 	ether_ifattach(ifp, adapter->hw.mac_addr, NULL);
2160 
2161 #ifdef PROFILE_SERIALIZER
2162 	SYSCTL_ADD_UINT(&adapter->sysctl_ctx,
2163 			SYSCTL_CHILDREN(adapter->sysctl_tree), OID_AUTO,
2164 			"serializer_sleep", CTLFLAG_RW,
2165 			&ifp->if_serializer->sleep_cnt, 0, NULL);
2166 	SYSCTL_ADD_UINT(&adapter->sysctl_ctx,
2167 			SYSCTL_CHILDREN(adapter->sysctl_tree), OID_AUTO,
2168 			"serializer_tryfail", CTLFLAG_RW,
2169 			&ifp->if_serializer->tryfail_cnt, 0, NULL);
2170 	SYSCTL_ADD_UINT(&adapter->sysctl_ctx,
2171 			SYSCTL_CHILDREN(adapter->sysctl_tree), OID_AUTO,
2172 			"serializer_enter", CTLFLAG_RW,
2173 			&ifp->if_serializer->enter_cnt, 0, NULL);
2174 	SYSCTL_ADD_UINT(&adapter->sysctl_ctx,
2175 			SYSCTL_CHILDREN(adapter->sysctl_tree), OID_AUTO,
2176 			"serializer_try", CTLFLAG_RW,
2177 			&ifp->if_serializer->try_cnt, 0, NULL);
2178 #endif
2179 
2180 	/*
2181 	 * Tell the upper layer(s) we support long frames.
2182 	 */
2183 	ifp->if_data.ifi_hdrlen = sizeof(struct ether_vlan_header);
2184 	ifp->if_capabilities |= IFCAP_VLAN_HWTAGGING | IFCAP_VLAN_MTU;
2185 #if 0
2186 	ifp->if_capenable |= IFCAP_VLAN_MTU;
2187 #endif
2188 
2189 	/*
2190 	 * Specify the media types supported by this adapter and register
2191 	 * callbacks to update media and link information
2192 	 */
2193 	ifmedia_init(&adapter->media, IFM_IMASK, em_media_change,
2194 		     em_media_status);
2195 	if (adapter->hw.media_type == em_media_type_fiber ||
2196 	    adapter->hw.media_type == em_media_type_internal_serdes) {
2197 		if (adapter->hw.mac_type == em_82545)
2198 			fiber_type = IFM_1000_LX;
2199 		ifmedia_add(&adapter->media, IFM_ETHER | fiber_type | IFM_FDX,
2200 			    0, NULL);
2201 		ifmedia_add(&adapter->media, IFM_ETHER | fiber_type, 0, NULL);
2202 	} else {
2203 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_10_T, 0, NULL);
2204 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_10_T | IFM_FDX,
2205 			    0, NULL);
2206 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_100_TX,
2207 			    0, NULL);
2208 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_100_TX | IFM_FDX,
2209 			    0, NULL);
2210 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_1000_T | IFM_FDX,
2211 			    0, NULL);
2212 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_1000_T, 0, NULL);
2213 	}
2214 	ifmedia_add(&adapter->media, IFM_ETHER | IFM_AUTO, 0, NULL);
2215 	ifmedia_set(&adapter->media, IFM_ETHER | IFM_AUTO);
2216 }
2217 
2218 /*********************************************************************
2219  *
2220  *  Workaround for SmartSpeed on 82541 and 82547 controllers
2221  *
2222  **********************************************************************/
2223 static void
2224 em_smartspeed(struct adapter *adapter)
2225 {
2226 	uint16_t phy_tmp;
2227 
2228 	if (adapter->link_active || (adapter->hw.phy_type != em_phy_igp) ||
2229 	    !adapter->hw.autoneg ||
2230 	    !(adapter->hw.autoneg_advertised & ADVERTISE_1000_FULL))
2231 		return;
2232 
2233 	if (adapter->smartspeed == 0) {
2234 		/*
2235 		 * If Master/Slave config fault is asserted twice,
2236 		 * we assume back-to-back.
2237 		 */
2238 		em_read_phy_reg(&adapter->hw, PHY_1000T_STATUS, &phy_tmp);
2239 		if (!(phy_tmp & SR_1000T_MS_CONFIG_FAULT))
2240 			return;
2241 		em_read_phy_reg(&adapter->hw, PHY_1000T_STATUS, &phy_tmp);
2242 		if (phy_tmp & SR_1000T_MS_CONFIG_FAULT) {
2243 			em_read_phy_reg(&adapter->hw, PHY_1000T_CTRL, &phy_tmp);
2244 			if (phy_tmp & CR_1000T_MS_ENABLE) {
2245 				phy_tmp &= ~CR_1000T_MS_ENABLE;
2246 				em_write_phy_reg(&adapter->hw,
2247 						 PHY_1000T_CTRL, phy_tmp);
2248 				adapter->smartspeed++;
2249 				if (adapter->hw.autoneg &&
2250 				    !em_phy_setup_autoneg(&adapter->hw) &&
2251 				    !em_read_phy_reg(&adapter->hw, PHY_CTRL,
2252 						     &phy_tmp)) {
2253 					phy_tmp |= (MII_CR_AUTO_NEG_EN |
2254 						    MII_CR_RESTART_AUTO_NEG);
2255 					em_write_phy_reg(&adapter->hw,
2256 							 PHY_CTRL, phy_tmp);
2257 				}
2258 			}
2259 		}
2260 		return;
2261 	} else if (adapter->smartspeed == EM_SMARTSPEED_DOWNSHIFT) {
2262 		/* If still no link, perhaps using 2/3 pair cable */
2263 		em_read_phy_reg(&adapter->hw, PHY_1000T_CTRL, &phy_tmp);
2264 		phy_tmp |= CR_1000T_MS_ENABLE;
2265 		em_write_phy_reg(&adapter->hw, PHY_1000T_CTRL, phy_tmp);
2266 		if (adapter->hw.autoneg &&
2267 		    !em_phy_setup_autoneg(&adapter->hw) &&
2268 		    !em_read_phy_reg(&adapter->hw, PHY_CTRL, &phy_tmp)) {
2269 			phy_tmp |= (MII_CR_AUTO_NEG_EN |
2270 				    MII_CR_RESTART_AUTO_NEG);
2271 			em_write_phy_reg(&adapter->hw, PHY_CTRL, phy_tmp);
2272 		}
2273 	}
2274 	/* Restart process after EM_SMARTSPEED_MAX iterations */
2275 	if (adapter->smartspeed++ == EM_SMARTSPEED_MAX)
2276 		adapter->smartspeed = 0;
2277 }
2278 
2279 /*
2280  * Manage DMA'able memory.
2281  */
2282 static void
2283 em_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error)
2284 {
2285 	if (error)
2286 		return;
2287 	*(bus_addr_t *)arg = segs->ds_addr;
2288 }
2289 
2290 static int
2291 em_dma_malloc(struct adapter *adapter, bus_size_t size,
2292 	      struct em_dma_alloc *dma)
2293 {
2294 	device_t dev = adapter->dev;
2295 	int error;
2296 
2297 	error = bus_dma_tag_create(NULL,		/* parent */
2298 				   EM_DBA_ALIGN, 0,	/* alignment, bounds */
2299 				   BUS_SPACE_MAXADDR,	/* lowaddr */
2300 				   BUS_SPACE_MAXADDR,	/* highaddr */
2301 				   NULL, NULL,		/* filter, filterarg */
2302 				   size,		/* maxsize */
2303 				   1,			/* nsegments */
2304 				   size,		/* maxsegsize */
2305 				   0,			/* flags */
2306 				   &dma->dma_tag);
2307 	if (error) {
2308 		device_printf(dev, "%s: bus_dma_tag_create failed; error %d\n",
2309 			      __func__, error);
2310 		return error;
2311 	}
2312 
2313 	error = bus_dmamem_alloc(dma->dma_tag, (void**)&dma->dma_vaddr,
2314 				 BUS_DMA_WAITOK, &dma->dma_map);
2315 	if (error) {
2316 		device_printf(dev, "%s: bus_dmammem_alloc failed; "
2317 			      "size %llu, error %d\n",
2318 			      __func__, (uintmax_t)size, error);
2319 		goto fail;
2320 	}
2321 
2322 	error = bus_dmamap_load(dma->dma_tag, dma->dma_map,
2323 				dma->dma_vaddr, size,
2324 				em_dmamap_cb, &dma->dma_paddr,
2325 				BUS_DMA_WAITOK);
2326 	if (error) {
2327 		device_printf(dev, "%s: bus_dmamap_load failed; error %u\n",
2328 			      __func__, error);
2329 		bus_dmamem_free(dma->dma_tag, dma->dma_vaddr, dma->dma_map);
2330 		goto fail;
2331 	}
2332 
2333 	return 0;
2334 fail:
2335 	bus_dma_tag_destroy(dma->dma_tag);
2336 	dma->dma_tag = NULL;
2337 	return error;
2338 }
2339 
2340 static void
2341 em_dma_free(struct adapter *adapter, struct em_dma_alloc *dma)
2342 {
2343 	if (dma->dma_tag != NULL) {
2344 		bus_dmamap_unload(dma->dma_tag, dma->dma_map);
2345 		bus_dmamem_free(dma->dma_tag, dma->dma_vaddr, dma->dma_map);
2346 		bus_dma_tag_destroy(dma->dma_tag);
2347 		dma->dma_tag = NULL;
2348 	}
2349 }
2350 
2351 /*********************************************************************
2352  *
2353  *  Allocate and initialize transmit structures.
2354  *
2355  **********************************************************************/
2356 static int
2357 em_setup_transmit_structures(struct adapter *adapter)
2358 {
2359 	struct em_buffer *tx_buffer;
2360 	bus_size_t size;
2361 	int error, i;
2362 
2363 	/*
2364 	 * Setup DMA descriptor areas.
2365 	 */
2366 	size = roundup2(adapter->hw.max_frame_size, MCLBYTES);
2367 	if (bus_dma_tag_create(NULL,			/* parent */
2368 			       1, 0,			/* alignment, bounds */
2369 			       BUS_SPACE_MAXADDR,	/* lowaddr */
2370 			       BUS_SPACE_MAXADDR,	/* highaddr */
2371 			       NULL, NULL,		/* filter, filterarg */
2372 			       size,			/* maxsize */
2373 			       EM_MAX_SCATTER,		/* nsegments */
2374 			       size,			/* maxsegsize */
2375 			       0,			/* flags */
2376 			       &adapter->txtag)) {
2377 		device_printf(adapter->dev, "Unable to allocate TX DMA tag\n");
2378 		return(ENOMEM);
2379 	}
2380 
2381 	adapter->tx_buffer_area =
2382 		kmalloc(sizeof(struct em_buffer) * adapter->num_tx_desc,
2383 			M_DEVBUF, M_WAITOK | M_ZERO);
2384 
2385 	bzero(adapter->tx_desc_base,
2386 	      sizeof(struct em_tx_desc) * adapter->num_tx_desc);
2387 	tx_buffer = adapter->tx_buffer_area;
2388 	for (i = 0; i < adapter->num_tx_desc; i++) {
2389 		error = bus_dmamap_create(adapter->txtag, 0, &tx_buffer->map);
2390 		if (error) {
2391 			device_printf(adapter->dev,
2392 				      "Unable to create TX DMA map\n");
2393 			goto fail;
2394 		}
2395 		tx_buffer++;
2396 	}
2397 
2398 	adapter->next_avail_tx_desc = 0;
2399 	adapter->next_tx_to_clean = 0;
2400 
2401 	/* Set number of descriptors available */
2402 	adapter->num_tx_desc_avail = adapter->num_tx_desc;
2403 
2404 	/* Set checksum context */
2405 	adapter->active_checksum_context = OFFLOAD_NONE;
2406 
2407 	bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
2408 			BUS_DMASYNC_PREWRITE);
2409 
2410 	return (0);
2411 fail:
2412 	em_free_transmit_structures(adapter);
2413 	return (error);
2414 }
2415 
2416 /*********************************************************************
2417  *
2418  *  Enable transmit unit.
2419  *
2420  **********************************************************************/
2421 static void
2422 em_initialize_transmit_unit(struct adapter *adapter)
2423 {
2424 	uint32_t reg_tctl;
2425 	uint32_t reg_tipg = 0;
2426 	uint64_t bus_addr;
2427 
2428 	INIT_DEBUGOUT("em_initialize_transmit_unit: begin");
2429 
2430 	/* Setup the Base and Length of the Tx Descriptor Ring */
2431 	bus_addr = adapter->txdma.dma_paddr;
2432 	E1000_WRITE_REG(&adapter->hw, TDLEN,
2433 			adapter->num_tx_desc * sizeof(struct em_tx_desc));
2434 	E1000_WRITE_REG(&adapter->hw, TDBAH, (uint32_t)(bus_addr >> 32));
2435 	E1000_WRITE_REG(&adapter->hw, TDBAL, (uint32_t)bus_addr);
2436 
2437 	/* Setup the HW Tx Head and Tail descriptor pointers */
2438 	E1000_WRITE_REG(&adapter->hw, TDT, 0);
2439 	E1000_WRITE_REG(&adapter->hw, TDH, 0);
2440 
2441 	HW_DEBUGOUT2("Base = %x, Length = %x\n",
2442 		     E1000_READ_REG(&adapter->hw, TDBAL),
2443 		     E1000_READ_REG(&adapter->hw, TDLEN));
2444 
2445 	/* Set the default values for the Tx Inter Packet Gap timer */
2446 	switch (adapter->hw.mac_type) {
2447 	case em_82542_rev2_0:
2448 	case em_82542_rev2_1:
2449 		reg_tipg = DEFAULT_82542_TIPG_IPGT;
2450 		reg_tipg |= DEFAULT_82542_TIPG_IPGR1 << E1000_TIPG_IPGR1_SHIFT;
2451 		reg_tipg |= DEFAULT_82542_TIPG_IPGR2 << E1000_TIPG_IPGR2_SHIFT;
2452 		break;
2453 	case em_80003es2lan:
2454 		reg_tipg = DEFAULT_82543_TIPG_IPGR1;
2455 		reg_tipg |=
2456 		    DEFAULT_80003ES2LAN_TIPG_IPGR2 << E1000_TIPG_IPGR2_SHIFT;
2457 		break;
2458 	default:
2459 		if (adapter->hw.media_type == em_media_type_fiber ||
2460 		    adapter->hw.media_type == em_media_type_internal_serdes)
2461 			reg_tipg = DEFAULT_82543_TIPG_IPGT_FIBER;
2462 		else
2463 			reg_tipg = DEFAULT_82543_TIPG_IPGT_COPPER;
2464 		reg_tipg |= DEFAULT_82543_TIPG_IPGR1 << E1000_TIPG_IPGR1_SHIFT;
2465 		reg_tipg |= DEFAULT_82543_TIPG_IPGR2 << E1000_TIPG_IPGR2_SHIFT;
2466 	}
2467 
2468 	E1000_WRITE_REG(&adapter->hw, TIPG, reg_tipg);
2469 	E1000_WRITE_REG(&adapter->hw, TIDV, adapter->tx_int_delay.value);
2470 	if (adapter->hw.mac_type >= em_82540) {
2471 		E1000_WRITE_REG(&adapter->hw, TADV,
2472 				adapter->tx_abs_int_delay.value);
2473 	}
2474 
2475 	/* Program the Transmit Control Register */
2476 	reg_tctl = E1000_TCTL_PSP | E1000_TCTL_EN |
2477 		   (E1000_COLLISION_THRESHOLD << E1000_CT_SHIFT);
2478 	if (adapter->hw.mac_type >= em_82571)
2479 		reg_tctl |= E1000_TCTL_MULR;
2480 	if (adapter->link_duplex == 1)
2481 		reg_tctl |= E1000_FDX_COLLISION_DISTANCE << E1000_COLD_SHIFT;
2482 	else
2483 		reg_tctl |= E1000_HDX_COLLISION_DISTANCE << E1000_COLD_SHIFT;
2484 
2485 	/* This write will effectively turn on the transmit unit. */
2486 	E1000_WRITE_REG(&adapter->hw, TCTL, reg_tctl);
2487 
2488 	/* Setup Transmit Descriptor Base Settings */
2489 	adapter->txd_cmd = E1000_TXD_CMD_IFCS;
2490 
2491 	if (adapter->tx_int_delay.value > 0)
2492 		adapter->txd_cmd |= E1000_TXD_CMD_IDE;
2493 }
2494 
2495 /*********************************************************************
2496  *
2497  *  Free all transmit related data structures.
2498  *
2499  **********************************************************************/
2500 static void
2501 em_free_transmit_structures(struct adapter *adapter)
2502 {
2503 	struct em_buffer *tx_buffer;
2504 	int i;
2505 
2506 	INIT_DEBUGOUT("free_transmit_structures: begin");
2507 
2508 	if (adapter->tx_buffer_area != NULL) {
2509 		tx_buffer = adapter->tx_buffer_area;
2510 		for (i = 0; i < adapter->num_tx_desc; i++, tx_buffer++) {
2511 			if (tx_buffer->m_head != NULL) {
2512 				bus_dmamap_unload(adapter->txtag,
2513 						  tx_buffer->map);
2514 				m_freem(tx_buffer->m_head);
2515 			}
2516 
2517 			if (tx_buffer->map != NULL) {
2518 				bus_dmamap_destroy(adapter->txtag, tx_buffer->map);
2519 				tx_buffer->map = NULL;
2520  			}
2521 			tx_buffer->m_head = NULL;
2522 		}
2523 	}
2524 	if (adapter->tx_buffer_area != NULL) {
2525 		kfree(adapter->tx_buffer_area, M_DEVBUF);
2526 		adapter->tx_buffer_area = NULL;
2527 	}
2528 	if (adapter->txtag != NULL) {
2529 		bus_dma_tag_destroy(adapter->txtag);
2530 		adapter->txtag = NULL;
2531 	}
2532 }
2533 
2534 /*********************************************************************
2535  *
2536  *  The offload context needs to be set when we transfer the first
2537  *  packet of a particular protocol (TCP/UDP). We change the
2538  *  context only if the protocol type changes.
2539  *
2540  **********************************************************************/
2541 static void
2542 em_transmit_checksum_setup(struct adapter *adapter,
2543 			   struct mbuf *mp,
2544 			   uint32_t *txd_upper,
2545 			   uint32_t *txd_lower)
2546 {
2547 	struct em_context_desc *TXD;
2548 	struct em_buffer *tx_buffer;
2549 	int curr_txd;
2550 
2551 	if (mp->m_pkthdr.csum_flags) {
2552 		if (mp->m_pkthdr.csum_flags & CSUM_TCP) {
2553 			*txd_upper = E1000_TXD_POPTS_TXSM << 8;
2554 			*txd_lower = E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D;
2555 			if (adapter->active_checksum_context == OFFLOAD_TCP_IP)
2556 				return;
2557 			else
2558 				adapter->active_checksum_context = OFFLOAD_TCP_IP;
2559 		} else if (mp->m_pkthdr.csum_flags & CSUM_UDP) {
2560 			*txd_upper = E1000_TXD_POPTS_TXSM << 8;
2561 			*txd_lower = E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D;
2562 			if (adapter->active_checksum_context == OFFLOAD_UDP_IP)
2563 				return;
2564 			else
2565 				adapter->active_checksum_context = OFFLOAD_UDP_IP;
2566 		} else {
2567 			*txd_upper = 0;
2568 			*txd_lower = 0;
2569 			return;
2570 		}
2571 	} else {
2572 		*txd_upper = 0;
2573 		*txd_lower = 0;
2574 		return;
2575 	}
2576 
2577 	/*
2578 	 * If we reach this point, the checksum offload context
2579 	 * needs to be reset.
2580 	 */
2581 	curr_txd = adapter->next_avail_tx_desc;
2582 	tx_buffer = &adapter->tx_buffer_area[curr_txd];
2583 	TXD = (struct em_context_desc *) &adapter->tx_desc_base[curr_txd];
2584 
2585 	TXD->lower_setup.ip_fields.ipcss = ETHER_HDR_LEN;
2586 	TXD->lower_setup.ip_fields.ipcso =
2587 	    ETHER_HDR_LEN + offsetof(struct ip, ip_sum);
2588 	TXD->lower_setup.ip_fields.ipcse =
2589 	    htole16(ETHER_HDR_LEN + sizeof(struct ip) - 1);
2590 
2591 	TXD->upper_setup.tcp_fields.tucss =
2592 	    ETHER_HDR_LEN + sizeof(struct ip);
2593 	TXD->upper_setup.tcp_fields.tucse = htole16(0);
2594 
2595 	if (adapter->active_checksum_context == OFFLOAD_TCP_IP) {
2596 		TXD->upper_setup.tcp_fields.tucso =
2597 			ETHER_HDR_LEN + sizeof(struct ip) +
2598 			offsetof(struct tcphdr, th_sum);
2599 	} else if (adapter->active_checksum_context == OFFLOAD_UDP_IP) {
2600 		TXD->upper_setup.tcp_fields.tucso =
2601 			ETHER_HDR_LEN + sizeof(struct ip) +
2602 			offsetof(struct udphdr, uh_sum);
2603 	}
2604 
2605 	TXD->tcp_seg_setup.data = htole32(0);
2606 	TXD->cmd_and_length = htole32(adapter->txd_cmd | E1000_TXD_CMD_DEXT);
2607 
2608 	tx_buffer->m_head = NULL;
2609 	tx_buffer->next_eop = -1;
2610 
2611 	if (++curr_txd == adapter->num_tx_desc)
2612 		curr_txd = 0;
2613 
2614 	adapter->num_tx_desc_avail--;
2615 	adapter->next_avail_tx_desc = curr_txd;
2616 }
2617 
2618 /**********************************************************************
2619  *
2620  *  Examine each tx_buffer in the used queue. If the hardware is done
2621  *  processing the packet then free associated resources. The
2622  *  tx_buffer is put back on the free queue.
2623  *
2624  **********************************************************************/
2625 
2626 static void
2627 em_txeof(struct adapter *adapter)
2628 {
2629 	int first, last, done, num_avail;
2630 	struct em_buffer *tx_buffer;
2631 	struct em_tx_desc *tx_desc, *eop_desc;
2632 	struct ifnet *ifp = &adapter->interface_data.ac_if;
2633 
2634 	if (adapter->num_tx_desc_avail == adapter->num_tx_desc)
2635 		return;
2636 
2637 	num_avail = adapter->num_tx_desc_avail;
2638 	first = adapter->next_tx_to_clean;
2639 	tx_desc = &adapter->tx_desc_base[first];
2640 	tx_buffer = &adapter->tx_buffer_area[first];
2641 	last = tx_buffer->next_eop;
2642 	KKASSERT(last >= 0 && last < adapter->num_tx_desc);
2643 	eop_desc = &adapter->tx_desc_base[last];
2644 
2645 	/*
2646 	 * Now caculate the terminating index for the cleanup loop below
2647 	 */
2648 	if (++last == adapter->num_tx_desc)
2649 		last = 0;
2650 	done = last;
2651 
2652 	bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
2653 			BUS_DMASYNC_POSTREAD);
2654 
2655 	while (eop_desc->upper.fields.status & E1000_TXD_STAT_DD) {
2656 		while (first != done) {
2657 			tx_desc->upper.data = 0;
2658 			tx_desc->lower.data = 0;
2659 			num_avail++;
2660 
2661 			logif(pkt_txclean);
2662 
2663 			if (tx_buffer->m_head) {
2664 				ifp->if_opackets++;
2665 				bus_dmamap_sync(adapter->txtag, tx_buffer->map,
2666 						BUS_DMASYNC_POSTWRITE);
2667 				bus_dmamap_unload(adapter->txtag,
2668 						  tx_buffer->map);
2669 
2670 				m_freem(tx_buffer->m_head);
2671 				tx_buffer->m_head = NULL;
2672 			}
2673 			tx_buffer->next_eop = -1;
2674 
2675 			if (++first == adapter->num_tx_desc)
2676 				first = 0;
2677 
2678 			tx_buffer = &adapter->tx_buffer_area[first];
2679 			tx_desc = &adapter->tx_desc_base[first];
2680 		}
2681 		/* See if we can continue to the next packet */
2682 		last = tx_buffer->next_eop;
2683 		if (last != -1) {
2684 			KKASSERT(last >= 0 && last < adapter->num_tx_desc);
2685 			eop_desc = &adapter->tx_desc_base[last];
2686 			if (++last == adapter->num_tx_desc)
2687 				last = 0;
2688 			done = last;
2689 		} else {
2690 			break;
2691 		}
2692 	}
2693 
2694 	bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
2695 			BUS_DMASYNC_PREWRITE);
2696 
2697 	adapter->next_tx_to_clean = first;
2698 
2699 	/*
2700 	 * If we have enough room, clear IFF_OACTIVE to tell the stack
2701 	 * that it is OK to send packets.
2702 	 * If there are no pending descriptors, clear the timeout. Otherwise,
2703 	 * if some descriptors have been freed, restart the timeout.
2704 	 */
2705 	if (num_avail > EM_TX_CLEANUP_THRESHOLD) {
2706 		ifp->if_flags &= ~IFF_OACTIVE;
2707 		if (num_avail == adapter->num_tx_desc)
2708 			ifp->if_timer = 0;
2709 		else if (num_avail == adapter->num_tx_desc_avail)
2710 			ifp->if_timer = EM_TX_TIMEOUT;
2711 	}
2712 	adapter->num_tx_desc_avail = num_avail;
2713 }
2714 
2715 /*********************************************************************
2716  *
2717  *  Get a buffer from system mbuf buffer pool.
2718  *
2719  **********************************************************************/
2720 static int
2721 em_get_buf(int i, struct adapter *adapter, struct mbuf *nmp, int how)
2722 {
2723 	struct mbuf *mp = nmp;
2724 	struct em_buffer *rx_buffer;
2725 	struct ifnet *ifp;
2726 	bus_addr_t paddr;
2727 	int error;
2728 
2729 	ifp = &adapter->interface_data.ac_if;
2730 
2731 	if (mp == NULL) {
2732 		mp = m_getcl(how, MT_DATA, M_PKTHDR);
2733 		if (mp == NULL) {
2734 			adapter->mbuf_cluster_failed++;
2735 			return (ENOBUFS);
2736 		}
2737 		mp->m_len = mp->m_pkthdr.len = MCLBYTES;
2738 	} else {
2739 		mp->m_len = mp->m_pkthdr.len = MCLBYTES;
2740 		mp->m_data = mp->m_ext.ext_buf;
2741 		mp->m_next = NULL;
2742 	}
2743 
2744 	if (ifp->if_mtu <= ETHERMTU)
2745 		m_adj(mp, ETHER_ALIGN);
2746 
2747 	rx_buffer = &adapter->rx_buffer_area[i];
2748 
2749 	/*
2750 	 * Using memory from the mbuf cluster pool, invoke the
2751 	 * bus_dma machinery to arrange the memory mapping.
2752 	 */
2753 	error = bus_dmamap_load(adapter->rxtag, rx_buffer->map,
2754 				mtod(mp, void *), mp->m_len,
2755 				em_dmamap_cb, &paddr, 0);
2756 	if (error) {
2757 		m_freem(mp);
2758 		return (error);
2759 	}
2760 	rx_buffer->m_head = mp;
2761 	adapter->rx_desc_base[i].buffer_addr = htole64(paddr);
2762 	bus_dmamap_sync(adapter->rxtag, rx_buffer->map, BUS_DMASYNC_PREREAD);
2763 
2764 	return (0);
2765 }
2766 
2767 /*********************************************************************
2768  *
2769  *  Allocate memory for rx_buffer structures. Since we use one
2770  *  rx_buffer per received packet, the maximum number of rx_buffer's
2771  *  that we'll need is equal to the number of receive descriptors
2772  *  that we've allocated.
2773  *
2774  **********************************************************************/
2775 static int
2776 em_allocate_receive_structures(struct adapter *adapter)
2777 {
2778 	int i, error, size;
2779 	struct em_buffer *rx_buffer;
2780 
2781 	size = adapter->num_rx_desc * sizeof(struct em_buffer);
2782 	adapter->rx_buffer_area = kmalloc(size, M_DEVBUF, M_WAITOK | M_ZERO);
2783 
2784 	error = bus_dma_tag_create(NULL,		/* parent */
2785 				   1, 0,		/* alignment, bounds */
2786 				   BUS_SPACE_MAXADDR,	/* lowaddr */
2787 				   BUS_SPACE_MAXADDR,	/* highaddr */
2788 				   NULL, NULL,		/* filter, filterarg */
2789 				   MCLBYTES,		/* maxsize */
2790 				   1,			/* nsegments */
2791 				   MCLBYTES,		/* maxsegsize */
2792 				   0,			/* flags */
2793 				   &adapter->rxtag);
2794 	if (error) {
2795 		device_printf(adapter->dev, "%s: bus_dma_tag_create failed; "
2796 			      "error %u\n", __func__, error);
2797 		goto fail;
2798 	}
2799 
2800 	rx_buffer = adapter->rx_buffer_area;
2801 	for (i = 0; i < adapter->num_rx_desc; i++, rx_buffer++) {
2802 		error = bus_dmamap_create(adapter->rxtag, BUS_DMA_NOWAIT,
2803 					  &rx_buffer->map);
2804 		if (error) {
2805 			device_printf(adapter->dev,
2806 				      "%s: bus_dmamap_create failed; "
2807 				      "error %u\n", __func__, error);
2808 			goto fail;
2809 		}
2810 	}
2811 
2812 	for (i = 0; i < adapter->num_rx_desc; i++) {
2813 		error = em_get_buf(i, adapter, NULL, MB_DONTWAIT);
2814 		if (error)
2815 			goto fail;
2816 	}
2817 
2818 	bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
2819 			BUS_DMASYNC_PREWRITE);
2820 
2821 	return (0);
2822 fail:
2823 	em_free_receive_structures(adapter);
2824 	return (error);
2825 }
2826 
2827 /*********************************************************************
2828  *
2829  *  Allocate and initialize receive structures.
2830  *
2831  **********************************************************************/
2832 static int
2833 em_setup_receive_structures(struct adapter *adapter)
2834 {
2835 	int error;
2836 
2837 	bzero(adapter->rx_desc_base,
2838 	      sizeof(struct em_rx_desc) * adapter->num_rx_desc);
2839 
2840 	error = em_allocate_receive_structures(adapter);
2841 	if (error)
2842 		return (error);
2843 
2844 	/* Setup our descriptor pointers */
2845 	adapter->next_rx_desc_to_check = 0;
2846 
2847 	return (0);
2848 }
2849 
2850 /*********************************************************************
2851  *
2852  *  Enable receive unit.
2853  *
2854  **********************************************************************/
2855 static void
2856 em_initialize_receive_unit(struct adapter *adapter)
2857 {
2858 	uint32_t reg_rctl;
2859 	uint32_t reg_rxcsum;
2860 	struct ifnet *ifp;
2861 	uint64_t bus_addr;
2862 
2863 	INIT_DEBUGOUT("em_initialize_receive_unit: begin");
2864 
2865 	ifp = &adapter->interface_data.ac_if;
2866 
2867 	/*
2868 	 * Make sure receives are disabled while setting
2869 	 * up the descriptor ring
2870 	 */
2871 	E1000_WRITE_REG(&adapter->hw, RCTL, 0);
2872 
2873 	/* Set the Receive Delay Timer Register */
2874 	E1000_WRITE_REG(&adapter->hw, RDTR,
2875 			adapter->rx_int_delay.value | E1000_RDT_FPDB);
2876 
2877 	if(adapter->hw.mac_type >= em_82540) {
2878 		E1000_WRITE_REG(&adapter->hw, RADV,
2879 				adapter->rx_abs_int_delay.value);
2880 
2881 		/* Set the interrupt throttling rate in 256ns increments */
2882 		if (em_int_throttle_ceil) {
2883 			E1000_WRITE_REG(&adapter->hw, ITR,
2884 				1000000000 / 256 / em_int_throttle_ceil);
2885 		} else {
2886 			E1000_WRITE_REG(&adapter->hw, ITR, 0);
2887 		}
2888 	}
2889 
2890 	/* Setup the Base and Length of the Rx Descriptor Ring */
2891 	bus_addr = adapter->rxdma.dma_paddr;
2892 	E1000_WRITE_REG(&adapter->hw, RDLEN, adapter->num_rx_desc *
2893 			sizeof(struct em_rx_desc));
2894 	E1000_WRITE_REG(&adapter->hw, RDBAH, (uint32_t)(bus_addr >> 32));
2895 	E1000_WRITE_REG(&adapter->hw, RDBAL, (uint32_t)bus_addr);
2896 
2897 	/* Setup the Receive Control Register */
2898 	reg_rctl = E1000_RCTL_EN | E1000_RCTL_BAM | E1000_RCTL_LBM_NO |
2899 		   E1000_RCTL_RDMTS_HALF |
2900 		   (adapter->hw.mc_filter_type << E1000_RCTL_MO_SHIFT);
2901 
2902 	if (adapter->hw.tbi_compatibility_on == TRUE)
2903 		reg_rctl |= E1000_RCTL_SBP;
2904 
2905 	switch (adapter->rx_buffer_len) {
2906 	default:
2907 	case EM_RXBUFFER_2048:
2908 		reg_rctl |= E1000_RCTL_SZ_2048;
2909 		break;
2910 	case EM_RXBUFFER_4096:
2911 		reg_rctl |= E1000_RCTL_SZ_4096 | E1000_RCTL_BSEX |
2912 			    E1000_RCTL_LPE;
2913 		break;
2914 	case EM_RXBUFFER_8192:
2915 		reg_rctl |= E1000_RCTL_SZ_8192 | E1000_RCTL_BSEX |
2916 			    E1000_RCTL_LPE;
2917 		break;
2918 	case EM_RXBUFFER_16384:
2919 		reg_rctl |= E1000_RCTL_SZ_16384 | E1000_RCTL_BSEX |
2920 			    E1000_RCTL_LPE;
2921 		break;
2922 	}
2923 
2924 	if (ifp->if_mtu > ETHERMTU)
2925 		reg_rctl |= E1000_RCTL_LPE;
2926 
2927 	/* Enable 82543 Receive Checksum Offload for TCP and UDP */
2928 	if ((adapter->hw.mac_type >= em_82543) &&
2929 	    (ifp->if_capenable & IFCAP_RXCSUM)) {
2930 		reg_rxcsum = E1000_READ_REG(&adapter->hw, RXCSUM);
2931 		reg_rxcsum |= (E1000_RXCSUM_IPOFL | E1000_RXCSUM_TUOFL);
2932 		E1000_WRITE_REG(&adapter->hw, RXCSUM, reg_rxcsum);
2933 	}
2934 
2935 #ifdef EM_X60_WORKAROUND
2936 	if (adapter->hw.mac_type == em_82573)
2937 		E1000_WRITE_REG(&adapter->hw, RDTR, 32);
2938 #endif
2939 
2940 	/* Enable Receives */
2941 	E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
2942 
2943 	/* Setup the HW Rx Head and Tail Descriptor Pointers */
2944 	E1000_WRITE_REG(&adapter->hw, RDH, 0);
2945 	E1000_WRITE_REG(&adapter->hw, RDT, adapter->num_rx_desc - 1);
2946 }
2947 
2948 /*********************************************************************
2949  *
2950  *  Free receive related data structures.
2951  *
2952  **********************************************************************/
2953 static void
2954 em_free_receive_structures(struct adapter *adapter)
2955 {
2956 	struct em_buffer *rx_buffer;
2957 	int i;
2958 
2959 	INIT_DEBUGOUT("free_receive_structures: begin");
2960 
2961 	if (adapter->rx_buffer_area != NULL) {
2962 		rx_buffer = adapter->rx_buffer_area;
2963 		for (i = 0; i < adapter->num_rx_desc; i++, rx_buffer++) {
2964 			if (rx_buffer->m_head != NULL) {
2965 				bus_dmamap_unload(adapter->rxtag,
2966 						  rx_buffer->map);
2967 				m_freem(rx_buffer->m_head);
2968 				rx_buffer->m_head = NULL;
2969 			}
2970 			if (rx_buffer->map != NULL) {
2971 				bus_dmamap_destroy(adapter->rxtag,
2972 						   rx_buffer->map);
2973 				rx_buffer->map = NULL;
2974 			}
2975 		}
2976 	}
2977 	if (adapter->rx_buffer_area != NULL) {
2978 		kfree(adapter->rx_buffer_area, M_DEVBUF);
2979 		adapter->rx_buffer_area = NULL;
2980 	}
2981 	if (adapter->rxtag != NULL) {
2982 		bus_dma_tag_destroy(adapter->rxtag);
2983 		adapter->rxtag = NULL;
2984 	}
2985 }
2986 
2987 /*********************************************************************
2988  *
2989  *  This routine executes in interrupt context. It replenishes
2990  *  the mbufs in the descriptor and sends data which has been
2991  *  dma'ed into host memory to upper layer.
2992  *
2993  *  We loop at most count times if count is > 0, or until done if
2994  *  count < 0.
2995  *
2996  *********************************************************************/
2997 static void
2998 em_rxeof(struct adapter *adapter, int count)
2999 {
3000 	struct ifnet *ifp;
3001 	struct mbuf *mp;
3002 	uint8_t accept_frame = 0;
3003 	uint8_t eop = 0;
3004 	uint16_t len, desc_len, prev_len_adj;
3005 	int i;
3006 
3007 	/* Pointer to the receive descriptor being examined. */
3008 	struct em_rx_desc *current_desc;
3009 
3010 	ifp = &adapter->interface_data.ac_if;
3011 	i = adapter->next_rx_desc_to_check;
3012 	current_desc = &adapter->rx_desc_base[i];
3013 
3014 	bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
3015 			BUS_DMASYNC_POSTREAD);
3016 
3017 	if (!(current_desc->status & E1000_RXD_STAT_DD))
3018 		return;
3019 
3020 	while ((current_desc->status & E1000_RXD_STAT_DD) && count != 0) {
3021 		logif(pkt_receive);
3022 		mp = adapter->rx_buffer_area[i].m_head;
3023 		bus_dmamap_sync(adapter->rxtag, adapter->rx_buffer_area[i].map,
3024 				BUS_DMASYNC_POSTREAD);
3025 		bus_dmamap_unload(adapter->rxtag,
3026 				  adapter->rx_buffer_area[i].map);
3027 
3028 		accept_frame = 1;
3029 		prev_len_adj = 0;
3030 		desc_len = le16toh(current_desc->length);
3031 		if (current_desc->status & E1000_RXD_STAT_EOP) {
3032 			count--;
3033 			eop = 1;
3034 			if (desc_len < ETHER_CRC_LEN) {
3035 				len = 0;
3036 				prev_len_adj = ETHER_CRC_LEN - desc_len;
3037 			} else {
3038 				len = desc_len - ETHER_CRC_LEN;
3039 			}
3040 		} else {
3041 			eop = 0;
3042 			len = desc_len;
3043 		}
3044 
3045 		if (current_desc->errors & E1000_RXD_ERR_FRAME_ERR_MASK) {
3046 			uint8_t last_byte;
3047 			uint32_t pkt_len = desc_len;
3048 
3049 			if (adapter->fmp != NULL)
3050 				pkt_len += adapter->fmp->m_pkthdr.len;
3051 
3052 			last_byte = *(mtod(mp, caddr_t) + desc_len - 1);
3053 
3054 			if (TBI_ACCEPT(&adapter->hw, current_desc->status,
3055 				       current_desc->errors,
3056 				       pkt_len, last_byte)) {
3057 				em_tbi_adjust_stats(&adapter->hw,
3058 						    &adapter->stats,
3059 						    pkt_len,
3060 						    adapter->hw.mac_addr);
3061 				if (len > 0)
3062 					len--;
3063 			} else {
3064 				accept_frame = 0;
3065 			}
3066 		}
3067 
3068 		if (accept_frame) {
3069 			if (em_get_buf(i, adapter, NULL, MB_DONTWAIT) == ENOBUFS) {
3070 				adapter->dropped_pkts++;
3071 				em_get_buf(i, adapter, mp, MB_DONTWAIT);
3072 				if (adapter->fmp != NULL)
3073 					m_freem(adapter->fmp);
3074 				adapter->fmp = NULL;
3075 				adapter->lmp = NULL;
3076 				goto skip;
3077 			}
3078 
3079 			/* Assign correct length to the current fragment */
3080 			mp->m_len = len;
3081 
3082 			if (adapter->fmp == NULL) {
3083 				mp->m_pkthdr.len = len;
3084 				adapter->fmp = mp;	 /* Store the first mbuf */
3085 				adapter->lmp = mp;
3086 			} else {
3087 				/* Chain mbuf's together */
3088 				/*
3089 				 * Adjust length of previous mbuf in chain if
3090 				 * we received less than 4 bytes in the last
3091 				 * descriptor.
3092 				 */
3093 				if (prev_len_adj > 0) {
3094 					adapter->lmp->m_len -= prev_len_adj;
3095 					adapter->fmp->m_pkthdr.len -= prev_len_adj;
3096 				}
3097 				adapter->lmp->m_next = mp;
3098 				adapter->lmp = adapter->lmp->m_next;
3099 				adapter->fmp->m_pkthdr.len += len;
3100 			}
3101 
3102 			if (eop) {
3103 				adapter->fmp->m_pkthdr.rcvif = ifp;
3104 				ifp->if_ipackets++;
3105 
3106 				em_receive_checksum(adapter, current_desc,
3107 						    adapter->fmp);
3108 				if (current_desc->status & E1000_RXD_STAT_VP) {
3109 					VLAN_INPUT_TAG(adapter->fmp,
3110 						       (current_desc->special &
3111 							E1000_RXD_SPC_VLAN_MASK));
3112 				} else {
3113 					ifp->if_input(ifp, adapter->fmp);
3114 				}
3115 				adapter->fmp = NULL;
3116 				adapter->lmp = NULL;
3117 			}
3118 		} else {
3119 			adapter->dropped_pkts++;
3120 			em_get_buf(i, adapter, mp, MB_DONTWAIT);
3121 			if (adapter->fmp != NULL)
3122 				m_freem(adapter->fmp);
3123 			adapter->fmp = NULL;
3124 			adapter->lmp = NULL;
3125 		}
3126 
3127 skip:
3128 		/* Zero out the receive descriptors status. */
3129 		current_desc->status = 0;
3130 
3131 		/* Advance our pointers to the next descriptor. */
3132 		if (++i == adapter->num_rx_desc) {
3133 			i = 0;
3134 			current_desc = adapter->rx_desc_base;
3135 		} else {
3136 			current_desc++;
3137 		}
3138 	}
3139 
3140 	bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
3141 			BUS_DMASYNC_PREWRITE);
3142 
3143 	adapter->next_rx_desc_to_check = i;
3144 
3145 	/* Advance the E1000's Receive Queue #0  "Tail Pointer". */
3146 	if (--i < 0)
3147 		i = adapter->num_rx_desc - 1;
3148 
3149 	E1000_WRITE_REG(&adapter->hw, RDT, i);
3150 }
3151 
3152 /*********************************************************************
3153  *
3154  *  Verify that the hardware indicated that the checksum is valid.
3155  *  Inform the stack about the status of checksum so that stack
3156  *  doesn't spend time verifying the checksum.
3157  *
3158  *********************************************************************/
3159 static void
3160 em_receive_checksum(struct adapter *adapter,
3161 		    struct em_rx_desc *rx_desc,
3162 		    struct mbuf *mp)
3163 {
3164 	/* 82543 or newer only */
3165 	if ((adapter->hw.mac_type < em_82543) ||
3166 	    /* Ignore Checksum bit is set */
3167 	    (rx_desc->status & E1000_RXD_STAT_IXSM)) {
3168 		mp->m_pkthdr.csum_flags = 0;
3169 		return;
3170 	}
3171 
3172 	if (rx_desc->status & E1000_RXD_STAT_IPCS) {
3173 		/* Did it pass? */
3174 		if (!(rx_desc->errors & E1000_RXD_ERR_IPE)) {
3175 			/* IP Checksum Good */
3176 			mp->m_pkthdr.csum_flags = CSUM_IP_CHECKED;
3177 			mp->m_pkthdr.csum_flags |= CSUM_IP_VALID;
3178 		} else {
3179 			mp->m_pkthdr.csum_flags = 0;
3180 		}
3181 	}
3182 
3183 	if (rx_desc->status & E1000_RXD_STAT_TCPCS) {
3184 		/* Did it pass? */
3185 		if (!(rx_desc->errors & E1000_RXD_ERR_TCPE)) {
3186 			mp->m_pkthdr.csum_flags |=
3187 			(CSUM_DATA_VALID | CSUM_PSEUDO_HDR |
3188 			 CSUM_FRAG_NOT_CHECKED);
3189 			mp->m_pkthdr.csum_data = htons(0xffff);
3190 		}
3191 	}
3192 }
3193 
3194 
3195 static void
3196 em_enable_vlans(struct adapter *adapter)
3197 {
3198 	uint32_t ctrl;
3199 
3200 	E1000_WRITE_REG(&adapter->hw, VET, ETHERTYPE_VLAN);
3201 
3202 	ctrl = E1000_READ_REG(&adapter->hw, CTRL);
3203 	ctrl |= E1000_CTRL_VME;
3204 	E1000_WRITE_REG(&adapter->hw, CTRL, ctrl);
3205 }
3206 
3207 static void
3208 em_disable_vlans(struct adapter *adapter)
3209 {
3210 	uint32_t ctrl;
3211 
3212 	ctrl = E1000_READ_REG(&adapter->hw, CTRL);
3213 	ctrl &= ~E1000_CTRL_VME;
3214 	E1000_WRITE_REG(&adapter->hw, CTRL, ctrl);
3215 }
3216 
3217 /*
3218  * note: we must call bus_enable_intr() prior to enabling the hardware
3219  * interrupt and bus_disable_intr() after disabling the hardware interrupt
3220  * in order to avoid handler execution races from scheduled interrupt
3221  * threads.
3222  */
3223 static void
3224 em_enable_intr(struct adapter *adapter)
3225 {
3226 	struct ifnet *ifp = &adapter->interface_data.ac_if;
3227 
3228 	if ((ifp->if_flags & IFF_POLLING) == 0) {
3229 		lwkt_serialize_handler_enable(ifp->if_serializer);
3230 		E1000_WRITE_REG(&adapter->hw, IMS, (IMS_ENABLE_MASK));
3231 	}
3232 }
3233 
3234 static void
3235 em_disable_intr(struct adapter *adapter)
3236 {
3237 	/*
3238 	 * The first version of 82542 had an errata where when link was forced
3239 	 * it would stay up even up even if the cable was disconnected.
3240 	 * Sequence errors were used to detect the disconnect and then the
3241 	 * driver would unforce the link.  This code in the in the ISR.  For
3242 	 * this to work correctly the Sequence error interrupt had to be
3243 	 * enabled all the time.
3244 	 */
3245 	if (adapter->hw.mac_type == em_82542_rev2_0) {
3246 		E1000_WRITE_REG(&adapter->hw, IMC,
3247 				(0xffffffff & ~E1000_IMC_RXSEQ));
3248 	} else {
3249 		E1000_WRITE_REG(&adapter->hw, IMC, 0xffffffff);
3250 	}
3251 
3252 	lwkt_serialize_handler_disable(adapter->interface_data.ac_if.if_serializer);
3253 }
3254 
3255 static int
3256 em_is_valid_ether_addr(uint8_t *addr)
3257 {
3258 	static const char zero_addr[6] = { 0, 0, 0, 0, 0, 0 };
3259 
3260 	if ((addr[0] & 1) || !bcmp(addr, zero_addr, ETHER_ADDR_LEN))
3261 		return (FALSE);
3262 	else
3263 		return (TRUE);
3264 }
3265 
3266 void
3267 em_write_pci_cfg(struct em_hw *hw, uint32_t reg, uint16_t *value)
3268 {
3269 	pci_write_config(((struct em_osdep *)hw->back)->dev, reg, *value, 2);
3270 }
3271 
3272 void
3273 em_read_pci_cfg(struct em_hw *hw, uint32_t reg, uint16_t *value)
3274 {
3275 	*value = pci_read_config(((struct em_osdep *)hw->back)->dev, reg, 2);
3276 }
3277 
3278 void
3279 em_pci_set_mwi(struct em_hw *hw)
3280 {
3281 	pci_write_config(((struct em_osdep *)hw->back)->dev, PCIR_COMMAND,
3282 			 (hw->pci_cmd_word | CMD_MEM_WRT_INVALIDATE), 2);
3283 }
3284 
3285 void
3286 em_pci_clear_mwi(struct em_hw *hw)
3287 {
3288 	pci_write_config(((struct em_osdep *)hw->back)->dev, PCIR_COMMAND,
3289 			 (hw->pci_cmd_word & ~CMD_MEM_WRT_INVALIDATE), 2);
3290 }
3291 
3292 uint32_t
3293 em_io_read(struct em_hw *hw, unsigned long port)
3294 {
3295 	struct em_osdep *io = hw->back;
3296 
3297 	return bus_space_read_4(io->io_bus_space_tag,
3298 				io->io_bus_space_handle, port);
3299 }
3300 
3301 void
3302 em_io_write(struct em_hw *hw, unsigned long port, uint32_t value)
3303 {
3304 	struct em_osdep *io = hw->back;
3305 
3306 	bus_space_write_4(io->io_bus_space_tag,
3307 			  io->io_bus_space_handle, port, value);
3308 }
3309 
3310 /*
3311  * We may eventually really do this, but its unnecessary
3312  * for now so we just return unsupported.
3313  */
3314 int32_t
3315 em_read_pcie_cap_reg(struct em_hw *hw, uint32_t reg, uint16_t *value)
3316 {
3317 	return (0);
3318 }
3319 
3320 
3321 /*********************************************************************
3322  * 82544 Coexistence issue workaround.
3323  *    There are 2 issues.
3324  *	1. Transmit Hang issue.
3325  *    To detect this issue, following equation can be used...
3326  *          SIZE[3:0] + ADDR[2:0] = SUM[3:0].
3327  *          If SUM[3:0] is in between 1 to 4, we will have this issue.
3328  *
3329  *	2. DAC issue.
3330  *    To detect this issue, following equation can be used...
3331  *          SIZE[3:0] + ADDR[2:0] = SUM[3:0].
3332  *          If SUM[3:0] is in between 9 to c, we will have this issue.
3333  *
3334  *
3335  *    WORKAROUND:
3336  *          Make sure we do not have ending address as 1,2,3,4(Hang) or
3337  *          9,a,b,c (DAC)
3338  *
3339 *************************************************************************/
3340 static uint32_t
3341 em_fill_descriptors(bus_addr_t address, uint32_t length, PDESC_ARRAY desc_array)
3342 {
3343 	/* Since issue is sensitive to length and address.*/
3344 	/* Let us first check the address...*/
3345 	uint32_t safe_terminator;
3346 	if (length <= 4) {
3347 		desc_array->descriptor[0].address = address;
3348 		desc_array->descriptor[0].length = length;
3349 		desc_array->elements = 1;
3350 		return (desc_array->elements);
3351 	}
3352 	safe_terminator = (uint32_t)((((uint32_t)address & 0x7) + (length & 0xF)) & 0xF);
3353 	/* if it does not fall between 0x1 to 0x4 and 0x9 to 0xC then return */
3354 	if (safe_terminator == 0 ||
3355 	    (safe_terminator > 4 && safe_terminator < 9) ||
3356 	    (safe_terminator > 0xC && safe_terminator <= 0xF)) {
3357 		desc_array->descriptor[0].address = address;
3358 		desc_array->descriptor[0].length = length;
3359 		desc_array->elements = 1;
3360 		return (desc_array->elements);
3361 	}
3362 
3363 	desc_array->descriptor[0].address = address;
3364 	desc_array->descriptor[0].length = length - 4;
3365 	desc_array->descriptor[1].address = address + (length - 4);
3366 	desc_array->descriptor[1].length = 4;
3367 	desc_array->elements = 2;
3368 	return (desc_array->elements);
3369 }
3370 
3371 /**********************************************************************
3372  *
3373  *  Update the board statistics counters.
3374  *
3375  **********************************************************************/
3376 static void
3377 em_update_stats_counters(struct adapter *adapter)
3378 {
3379 	struct ifnet   *ifp;
3380 
3381 	if (adapter->hw.media_type == em_media_type_copper ||
3382 	    (E1000_READ_REG(&adapter->hw, STATUS) & E1000_STATUS_LU)) {
3383 		adapter->stats.symerrs += E1000_READ_REG(&adapter->hw, SYMERRS);
3384 		adapter->stats.sec += E1000_READ_REG(&adapter->hw, SEC);
3385 	}
3386 	adapter->stats.crcerrs += E1000_READ_REG(&adapter->hw, CRCERRS);
3387 	adapter->stats.mpc += E1000_READ_REG(&adapter->hw, MPC);
3388 	adapter->stats.scc += E1000_READ_REG(&adapter->hw, SCC);
3389 	adapter->stats.ecol += E1000_READ_REG(&adapter->hw, ECOL);
3390 
3391 	adapter->stats.mcc += E1000_READ_REG(&adapter->hw, MCC);
3392 	adapter->stats.latecol += E1000_READ_REG(&adapter->hw, LATECOL);
3393 	adapter->stats.colc += E1000_READ_REG(&adapter->hw, COLC);
3394 	adapter->stats.dc += E1000_READ_REG(&adapter->hw, DC);
3395 	adapter->stats.rlec += E1000_READ_REG(&adapter->hw, RLEC);
3396 	adapter->stats.xonrxc += E1000_READ_REG(&adapter->hw, XONRXC);
3397 	adapter->stats.xontxc += E1000_READ_REG(&adapter->hw, XONTXC);
3398 	adapter->stats.xoffrxc += E1000_READ_REG(&adapter->hw, XOFFRXC);
3399 	adapter->stats.xofftxc += E1000_READ_REG(&adapter->hw, XOFFTXC);
3400 	adapter->stats.fcruc += E1000_READ_REG(&adapter->hw, FCRUC);
3401 	adapter->stats.prc64 += E1000_READ_REG(&adapter->hw, PRC64);
3402 	adapter->stats.prc127 += E1000_READ_REG(&adapter->hw, PRC127);
3403 	adapter->stats.prc255 += E1000_READ_REG(&adapter->hw, PRC255);
3404 	adapter->stats.prc511 += E1000_READ_REG(&adapter->hw, PRC511);
3405 	adapter->stats.prc1023 += E1000_READ_REG(&adapter->hw, PRC1023);
3406 	adapter->stats.prc1522 += E1000_READ_REG(&adapter->hw, PRC1522);
3407 	adapter->stats.gprc += E1000_READ_REG(&adapter->hw, GPRC);
3408 	adapter->stats.bprc += E1000_READ_REG(&adapter->hw, BPRC);
3409 	adapter->stats.mprc += E1000_READ_REG(&adapter->hw, MPRC);
3410 	adapter->stats.gptc += E1000_READ_REG(&adapter->hw, GPTC);
3411 
3412 	/* For the 64-bit byte counters the low dword must be read first. */
3413 	/* Both registers clear on the read of the high dword */
3414 
3415 	adapter->stats.gorcl += E1000_READ_REG(&adapter->hw, GORCL);
3416 	adapter->stats.gorch += E1000_READ_REG(&adapter->hw, GORCH);
3417 	adapter->stats.gotcl += E1000_READ_REG(&adapter->hw, GOTCL);
3418 	adapter->stats.gotch += E1000_READ_REG(&adapter->hw, GOTCH);
3419 
3420 	adapter->stats.rnbc += E1000_READ_REG(&adapter->hw, RNBC);
3421 	adapter->stats.ruc += E1000_READ_REG(&adapter->hw, RUC);
3422 	adapter->stats.rfc += E1000_READ_REG(&adapter->hw, RFC);
3423 	adapter->stats.roc += E1000_READ_REG(&adapter->hw, ROC);
3424 	adapter->stats.rjc += E1000_READ_REG(&adapter->hw, RJC);
3425 
3426 	adapter->stats.torl += E1000_READ_REG(&adapter->hw, TORL);
3427 	adapter->stats.torh += E1000_READ_REG(&adapter->hw, TORH);
3428 	adapter->stats.totl += E1000_READ_REG(&adapter->hw, TOTL);
3429 	adapter->stats.toth += E1000_READ_REG(&adapter->hw, TOTH);
3430 
3431 	adapter->stats.tpr += E1000_READ_REG(&adapter->hw, TPR);
3432 	adapter->stats.tpt += E1000_READ_REG(&adapter->hw, TPT);
3433 	adapter->stats.ptc64 += E1000_READ_REG(&adapter->hw, PTC64);
3434 	adapter->stats.ptc127 += E1000_READ_REG(&adapter->hw, PTC127);
3435 	adapter->stats.ptc255 += E1000_READ_REG(&adapter->hw, PTC255);
3436 	adapter->stats.ptc511 += E1000_READ_REG(&adapter->hw, PTC511);
3437 	adapter->stats.ptc1023 += E1000_READ_REG(&adapter->hw, PTC1023);
3438 	adapter->stats.ptc1522 += E1000_READ_REG(&adapter->hw, PTC1522);
3439 	adapter->stats.mptc += E1000_READ_REG(&adapter->hw, MPTC);
3440 	adapter->stats.bptc += E1000_READ_REG(&adapter->hw, BPTC);
3441 
3442 	if (adapter->hw.mac_type >= em_82543) {
3443 		adapter->stats.algnerrc +=
3444 		    E1000_READ_REG(&adapter->hw, ALGNERRC);
3445 		adapter->stats.rxerrc +=
3446 		    E1000_READ_REG(&adapter->hw, RXERRC);
3447 		adapter->stats.tncrs +=
3448 		    E1000_READ_REG(&adapter->hw, TNCRS);
3449 		adapter->stats.cexterr +=
3450 		    E1000_READ_REG(&adapter->hw, CEXTERR);
3451 		adapter->stats.tsctc +=
3452 		    E1000_READ_REG(&adapter->hw, TSCTC);
3453 		adapter->stats.tsctfc +=
3454 		    E1000_READ_REG(&adapter->hw, TSCTFC);
3455 	}
3456 	ifp = &adapter->interface_data.ac_if;
3457 
3458 	/* Fill out the OS statistics structure */
3459 	ifp->if_collisions = adapter->stats.colc;
3460 
3461 	/* Rx Errors */
3462 	ifp->if_ierrors =
3463 		adapter->dropped_pkts +
3464 		adapter->stats.rxerrc +
3465 		adapter->stats.crcerrs +
3466 		adapter->stats.algnerrc +
3467 		adapter->stats.ruc + adapter->stats.roc +
3468 		adapter->stats.mpc + adapter->stats.cexterr +
3469 		adapter->rx_overruns;
3470 
3471 	/* Tx Errors */
3472 	ifp->if_oerrors = adapter->stats.ecol + adapter->stats.latecol +
3473 			  adapter->watchdog_timeouts;
3474 }
3475 
3476 
3477 /**********************************************************************
3478  *
3479  *  This routine is called only when em_display_debug_stats is enabled.
3480  *  This routine provides a way to take a look at important statistics
3481  *  maintained by the driver and hardware.
3482  *
3483  **********************************************************************/
3484 static void
3485 em_print_debug_info(struct adapter *adapter)
3486 {
3487 	device_t dev= adapter->dev;
3488 	uint8_t *hw_addr = adapter->hw.hw_addr;
3489 
3490 	device_printf(dev, "Adapter hardware address = %p \n", hw_addr);
3491 	device_printf(dev, "CTRL  = 0x%x RCTL = 0x%x\n",
3492 		      E1000_READ_REG(&adapter->hw, CTRL),
3493 		      E1000_READ_REG(&adapter->hw, RCTL));
3494 	device_printf(dev, "Packet buffer = Tx=%dk Rx=%dk\n",
3495 		      ((E1000_READ_REG(&adapter->hw, PBA) & 0xffff0000) >> 16),
3496 		      (E1000_READ_REG(&adapter->hw, PBA) & 0xffff));
3497 	device_printf(dev, "Flow control watermarks high = %d low = %d\n",
3498 		      adapter->hw.fc_high_water, adapter->hw.fc_low_water);
3499 	device_printf(dev, "tx_int_delay = %d, tx_abs_int_delay = %d\n",
3500 		      E1000_READ_REG(&adapter->hw, TIDV),
3501 		      E1000_READ_REG(&adapter->hw, TADV));
3502 	device_printf(dev, "rx_int_delay = %d, rx_abs_int_delay = %d\n",
3503 		      E1000_READ_REG(&adapter->hw, RDTR),
3504 		      E1000_READ_REG(&adapter->hw, RADV));
3505 	device_printf(dev, "fifo workaround = %lld, fifo_reset_count = %lld\n",
3506 		      (long long)adapter->tx_fifo_wrk_cnt,
3507 		      (long long)adapter->tx_fifo_reset_cnt);
3508 	device_printf(dev, "hw tdh = %d, hw tdt = %d\n",
3509 		      E1000_READ_REG(&adapter->hw, TDH),
3510 		      E1000_READ_REG(&adapter->hw, TDT));
3511 	device_printf(dev, "Num Tx descriptors avail = %d\n",
3512 		      adapter->num_tx_desc_avail);
3513 	device_printf(dev, "Tx Descriptors not avail1 = %ld\n",
3514 		      adapter->no_tx_desc_avail1);
3515 	device_printf(dev, "Tx Descriptors not avail2 = %ld\n",
3516 		      adapter->no_tx_desc_avail2);
3517 	device_printf(dev, "Std mbuf failed = %ld\n",
3518 		      adapter->mbuf_alloc_failed);
3519 	device_printf(dev, "Std mbuf cluster failed = %ld\n",
3520 		      adapter->mbuf_cluster_failed);
3521 	device_printf(dev, "Driver dropped packets = %ld\n",
3522 		      adapter->dropped_pkts);
3523 }
3524 
3525 static void
3526 em_print_hw_stats(struct adapter *adapter)
3527 {
3528 	device_t dev= adapter->dev;
3529 
3530 	device_printf(dev, "Excessive collisions = %lld\n",
3531 		      (long long)adapter->stats.ecol);
3532 	device_printf(dev, "Symbol errors = %lld\n",
3533 		      (long long)adapter->stats.symerrs);
3534 	device_printf(dev, "Sequence errors = %lld\n",
3535 		      (long long)adapter->stats.sec);
3536 	device_printf(dev, "Defer count = %lld\n",
3537 		      (long long)adapter->stats.dc);
3538 
3539 	device_printf(dev, "Missed Packets = %lld\n",
3540 		      (long long)adapter->stats.mpc);
3541 	device_printf(dev, "Receive No Buffers = %lld\n",
3542 		      (long long)adapter->stats.rnbc);
3543 	/* RLEC is inaccurate on some hardware, calculate our own. */
3544 	device_printf(dev, "Receive Length errors = %lld\n",
3545 		      (long long)adapter->stats.roc +
3546 		      (long long)adapter->stats.ruc);
3547 	device_printf(dev, "Receive errors = %lld\n",
3548 		      (long long)adapter->stats.rxerrc);
3549 	device_printf(dev, "Crc errors = %lld\n",
3550 		      (long long)adapter->stats.crcerrs);
3551 	device_printf(dev, "Alignment errors = %lld\n",
3552 		      (long long)adapter->stats.algnerrc);
3553 	device_printf(dev, "Carrier extension errors = %lld\n",
3554 		      (long long)adapter->stats.cexterr);
3555 	device_printf(dev, "RX overruns = %lu\n", adapter->rx_overruns);
3556 	device_printf(dev, "Watchdog timeouts = %lu\n",
3557 		      adapter->watchdog_timeouts);
3558 
3559 	device_printf(dev, "XON Rcvd = %lld\n",
3560 		      (long long)adapter->stats.xonrxc);
3561 	device_printf(dev, "XON Xmtd = %lld\n",
3562 		      (long long)adapter->stats.xontxc);
3563 	device_printf(dev, "XOFF Rcvd = %lld\n",
3564 		      (long long)adapter->stats.xoffrxc);
3565 	device_printf(dev, "XOFF Xmtd = %lld\n",
3566 		      (long long)adapter->stats.xofftxc);
3567 
3568 	device_printf(dev, "Good Packets Rcvd = %lld\n",
3569 		      (long long)adapter->stats.gprc);
3570 	device_printf(dev, "Good Packets Xmtd = %lld\n",
3571 		      (long long)adapter->stats.gptc);
3572 }
3573 
3574 static int
3575 em_sysctl_debug_info(SYSCTL_HANDLER_ARGS)
3576 {
3577 	int error;
3578 	int result;
3579 	struct adapter *adapter;
3580 
3581 	result = -1;
3582 	error = sysctl_handle_int(oidp, &result, 0, req);
3583 
3584 	if (error || !req->newptr)
3585 		return (error);
3586 
3587 	if (result == 1) {
3588 		adapter = (struct adapter *)arg1;
3589 		em_print_debug_info(adapter);
3590 	}
3591 
3592 	return (error);
3593 }
3594 
3595 static int
3596 em_sysctl_stats(SYSCTL_HANDLER_ARGS)
3597 {
3598 	int error;
3599 	int result;
3600 	struct adapter *adapter;
3601 
3602 	result = -1;
3603 	error = sysctl_handle_int(oidp, &result, 0, req);
3604 
3605 	if (error || !req->newptr)
3606 		return (error);
3607 
3608 	if (result == 1) {
3609 		adapter = (struct adapter *)arg1;
3610 		em_print_hw_stats(adapter);
3611 	}
3612 
3613 	return (error);
3614 }
3615 
3616 static int
3617 em_sysctl_int_delay(SYSCTL_HANDLER_ARGS)
3618 {
3619 	struct em_int_delay_info *info;
3620 	struct adapter *adapter;
3621 	uint32_t regval;
3622 	int error;
3623 	int usecs;
3624 	int ticks;
3625 
3626 	info = (struct em_int_delay_info *)arg1;
3627 	adapter = info->adapter;
3628 	usecs = info->value;
3629 	error = sysctl_handle_int(oidp, &usecs, 0, req);
3630 	if (error != 0 || req->newptr == NULL)
3631 		return (error);
3632 	if (usecs < 0 || usecs > E1000_TICKS_TO_USECS(65535))
3633 		return (EINVAL);
3634 	info->value = usecs;
3635 	ticks = E1000_USECS_TO_TICKS(usecs);
3636 
3637 	lwkt_serialize_enter(adapter->interface_data.ac_if.if_serializer);
3638 	regval = E1000_READ_OFFSET(&adapter->hw, info->offset);
3639 	regval = (regval & ~0xffff) | (ticks & 0xffff);
3640 	/* Handle a few special cases. */
3641 	switch (info->offset) {
3642 	case E1000_RDTR:
3643 	case E1000_82542_RDTR:
3644 		regval |= E1000_RDT_FPDB;
3645 		break;
3646 	case E1000_TIDV:
3647 	case E1000_82542_TIDV:
3648 		if (ticks == 0) {
3649 			adapter->txd_cmd &= ~E1000_TXD_CMD_IDE;
3650 			/* Don't write 0 into the TIDV register. */
3651 			regval++;
3652 		} else
3653 			adapter->txd_cmd |= E1000_TXD_CMD_IDE;
3654 		break;
3655 	}
3656 	E1000_WRITE_OFFSET(&adapter->hw, info->offset, regval);
3657 	lwkt_serialize_exit(adapter->interface_data.ac_if.if_serializer);
3658 	return (0);
3659 }
3660 
3661 static void
3662 em_add_int_delay_sysctl(struct adapter *adapter, const char *name,
3663 			const char *description, struct em_int_delay_info *info,
3664 			int offset, int value)
3665 {
3666 	info->adapter = adapter;
3667 	info->offset = offset;
3668 	info->value = value;
3669 	SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
3670 			SYSCTL_CHILDREN(adapter->sysctl_tree),
3671 			OID_AUTO, name, CTLTYPE_INT|CTLFLAG_RW,
3672 			info, 0, em_sysctl_int_delay, "I", description);
3673 }
3674 
3675 static int
3676 em_sysctl_int_throttle(SYSCTL_HANDLER_ARGS)
3677 {
3678 	struct adapter *adapter = (void *)arg1;
3679 	int error;
3680 	int throttle;
3681 
3682 	throttle = em_int_throttle_ceil;
3683 	error = sysctl_handle_int(oidp, &throttle, 0, req);
3684 	if (error || req->newptr == NULL)
3685 		return error;
3686 	if (throttle < 0 || throttle > 1000000000 / 256)
3687 		return EINVAL;
3688 	if (throttle) {
3689 		/*
3690 		 * Set the interrupt throttling rate in 256ns increments,
3691 		 * recalculate sysctl value assignment to get exact frequency.
3692 		 */
3693 		throttle = 1000000000 / 256 / throttle;
3694 		lwkt_serialize_enter(adapter->interface_data.ac_if.if_serializer);
3695 		em_int_throttle_ceil = 1000000000 / 256 / throttle;
3696 		E1000_WRITE_REG(&adapter->hw, ITR, throttle);
3697 		lwkt_serialize_exit(adapter->interface_data.ac_if.if_serializer);
3698 	} else {
3699 		lwkt_serialize_enter(adapter->interface_data.ac_if.if_serializer);
3700 		em_int_throttle_ceil = 0;
3701 		E1000_WRITE_REG(&adapter->hw, ITR, 0);
3702 		lwkt_serialize_exit(adapter->interface_data.ac_if.if_serializer);
3703 	}
3704 	device_printf(adapter->dev, "Interrupt moderation set to %d/sec\n",
3705 			em_int_throttle_ceil);
3706 	return 0;
3707 }
3708