xref: /dflybsd-src/sys/dev/netif/em/if_em.c (revision 6d49aa6ffaff1e5a2ff3abe70c453cc8b47adb73)
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 1.57 2007/04/15 12:50:49 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 
99 #include <sys/param.h>
100 #include <sys/bus.h>
101 #include <sys/endian.h>
102 #include <sys/kernel.h>
103 #include <sys/ktr.h>
104 #include <sys/malloc.h>
105 #include <sys/mbuf.h>
106 #include <sys/module.h>
107 #include <sys/rman.h>
108 #include <sys/serialize.h>
109 #include <sys/socket.h>
110 #include <sys/sockio.h>
111 #include <sys/sysctl.h>
112 
113 #include <net/bpf.h>
114 #include <net/ethernet.h>
115 #include <net/if.h>
116 #include <net/if_arp.h>
117 #include <net/if_dl.h>
118 #include <net/if_media.h>
119 #include <net/if_types.h>
120 #include <net/ifq_var.h>
121 #include <net/vlan/if_vlan_var.h>
122 
123 #ifdef INET
124 #include <netinet/in.h>
125 #include <netinet/in_systm.h>
126 #include <netinet/in_var.h>
127 #include <netinet/ip.h>
128 #include <netinet/tcp.h>
129 #include <netinet/udp.h>
130 #endif
131 
132 #include <dev/netif/em/if_em_hw.h>
133 #include <dev/netif/em/if_em.h>
134 
135 #define EM_X60_WORKAROUND
136 
137 /*********************************************************************
138  *  Set this to one to display debug statistics
139  *********************************************************************/
140 int	em_display_debug_stats = 0;
141 
142 /*********************************************************************
143  *  Driver version
144  *********************************************************************/
145 
146 char em_driver_version[] = "6.2.9";
147 
148 
149 /*********************************************************************
150  *  PCI Device ID Table
151  *
152  *  Used by probe to select devices to load on
153  *  Last field stores an index into em_strings
154  *  Last entry must be all 0s
155  *
156  *  { Vendor ID, Device ID, SubVendor ID, SubDevice ID, String Index }
157  *********************************************************************/
158 
159 static em_vendor_info_t em_vendor_info_array[] =
160 {
161 	/* Intel(R) PRO/1000 Network Connection */
162 	{ 0x8086, E1000_DEV_ID_82540EM,		PCI_ANY_ID, PCI_ANY_ID, 0},
163 	{ 0x8086, E1000_DEV_ID_82540EM_LOM,	PCI_ANY_ID, PCI_ANY_ID, 0},
164 	{ 0x8086, E1000_DEV_ID_82540EP,		PCI_ANY_ID, PCI_ANY_ID, 0},
165 	{ 0x8086, E1000_DEV_ID_82540EP_LOM,	PCI_ANY_ID, PCI_ANY_ID, 0},
166 	{ 0x8086, E1000_DEV_ID_82540EP_LP,	PCI_ANY_ID, PCI_ANY_ID, 0},
167 
168 	{ 0x8086, E1000_DEV_ID_82541EI,		PCI_ANY_ID, PCI_ANY_ID, 0},
169 	{ 0x8086, E1000_DEV_ID_82541ER,		PCI_ANY_ID, PCI_ANY_ID, 0},
170 	{ 0x8086, E1000_DEV_ID_82541ER_LOM,	PCI_ANY_ID, PCI_ANY_ID, 0},
171 	{ 0x8086, E1000_DEV_ID_82541EI_MOBILE,	PCI_ANY_ID, PCI_ANY_ID, 0},
172 	{ 0x8086, E1000_DEV_ID_82541GI,		PCI_ANY_ID, PCI_ANY_ID, 0},
173 	{ 0x8086, E1000_DEV_ID_82541GI_LF,	PCI_ANY_ID, PCI_ANY_ID, 0},
174 	{ 0x8086, E1000_DEV_ID_82541GI_MOBILE,	PCI_ANY_ID, PCI_ANY_ID, 0},
175 
176 	{ 0x8086, E1000_DEV_ID_82542,		PCI_ANY_ID, PCI_ANY_ID, 0},
177 
178 	{ 0x8086, E1000_DEV_ID_82543GC_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
179 	{ 0x8086, E1000_DEV_ID_82543GC_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
180 
181 	{ 0x8086, E1000_DEV_ID_82544EI_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
182 	{ 0x8086, E1000_DEV_ID_82544EI_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
183 	{ 0x8086, E1000_DEV_ID_82544GC_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
184 	{ 0x8086, E1000_DEV_ID_82544GC_LOM,	PCI_ANY_ID, PCI_ANY_ID, 0},
185 
186 	{ 0x8086, E1000_DEV_ID_82545EM_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
187 	{ 0x8086, E1000_DEV_ID_82545EM_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
188 	{ 0x8086, E1000_DEV_ID_82545GM_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
189 	{ 0x8086, E1000_DEV_ID_82545GM_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
190 	{ 0x8086, E1000_DEV_ID_82545GM_SERDES,	PCI_ANY_ID, PCI_ANY_ID, 0},
191 
192 	{ 0x8086, E1000_DEV_ID_82546EB_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
193 	{ 0x8086, E1000_DEV_ID_82546EB_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
194 	{ 0x8086, E1000_DEV_ID_82546EB_QUAD_COPPER, PCI_ANY_ID, PCI_ANY_ID, 0},
195 	{ 0x8086, E1000_DEV_ID_82546GB_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
196 	{ 0x8086, E1000_DEV_ID_82546GB_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
197 	{ 0x8086, E1000_DEV_ID_82546GB_SERDES,	PCI_ANY_ID, PCI_ANY_ID, 0},
198 	{ 0x8086, E1000_DEV_ID_82546GB_PCIE,	PCI_ANY_ID, PCI_ANY_ID, 0},
199 	{ 0x8086, E1000_DEV_ID_82546GB_QUAD_COPPER, PCI_ANY_ID, PCI_ANY_ID, 0},
200 	{ 0x8086, E1000_DEV_ID_82546GB_QUAD_COPPER_KSP3,
201 						PCI_ANY_ID, PCI_ANY_ID, 0},
202 
203 	{ 0x8086, E1000_DEV_ID_82547EI,		PCI_ANY_ID, PCI_ANY_ID, 0},
204 	{ 0x8086, E1000_DEV_ID_82547EI_MOBILE,	PCI_ANY_ID, PCI_ANY_ID, 0},
205 	{ 0x8086, E1000_DEV_ID_82547GI,		PCI_ANY_ID, PCI_ANY_ID, 0},
206 
207 	{ 0x8086, E1000_DEV_ID_82571EB_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
208 	{ 0x8086, E1000_DEV_ID_82571EB_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
209 	{ 0x8086, E1000_DEV_ID_82571EB_SERDES,	PCI_ANY_ID, PCI_ANY_ID, 0},
210 	{ 0x8086, E1000_DEV_ID_82571EB_QUAD_COPPER,
211 						PCI_ANY_ID, PCI_ANY_ID, 0},
212 	{ 0x8086, E1000_DEV_ID_82571EB_QUAD_COPPER_LOWPROFILE,
213 						PCI_ANY_ID, PCI_ANY_ID, 0},
214 
215 	{ 0x8086, E1000_DEV_ID_82572EI_COPPER,	PCI_ANY_ID, PCI_ANY_ID, 0},
216 	{ 0x8086, E1000_DEV_ID_82572EI_FIBER,	PCI_ANY_ID, PCI_ANY_ID, 0},
217 	{ 0x8086, E1000_DEV_ID_82572EI_SERDES,	PCI_ANY_ID, PCI_ANY_ID, 0},
218 	{ 0x8086, E1000_DEV_ID_82572EI,		PCI_ANY_ID, PCI_ANY_ID, 0},
219 
220 	{ 0x8086, E1000_DEV_ID_82573E,		PCI_ANY_ID, PCI_ANY_ID, 0},
221 	{ 0x8086, E1000_DEV_ID_82573E_IAMT,	PCI_ANY_ID, PCI_ANY_ID, 0},
222 	{ 0x8086, E1000_DEV_ID_82573L,		PCI_ANY_ID, PCI_ANY_ID, 0},
223 
224 	{ 0x8086, E1000_DEV_ID_80003ES2LAN_COPPER_SPT,
225 						PCI_ANY_ID, PCI_ANY_ID, 0},
226 	{ 0x8086, E1000_DEV_ID_80003ES2LAN_SERDES_SPT,
227 						PCI_ANY_ID, PCI_ANY_ID, 0},
228 	{ 0x8086, E1000_DEV_ID_80003ES2LAN_COPPER_DPT,
229 						PCI_ANY_ID, PCI_ANY_ID, 0},
230 	{ 0x8086, E1000_DEV_ID_80003ES2LAN_SERDES_DPT,
231 						PCI_ANY_ID, PCI_ANY_ID, 0},
232 
233 	{ 0x8086, E1000_DEV_ID_ICH8_IGP_M_AMT,	PCI_ANY_ID, PCI_ANY_ID, 0},
234 	{ 0x8086, E1000_DEV_ID_ICH8_IGP_AMT,	PCI_ANY_ID, PCI_ANY_ID, 0},
235 	{ 0x8086, E1000_DEV_ID_ICH8_IGP_C,	PCI_ANY_ID, PCI_ANY_ID, 0},
236 	{ 0x8086, E1000_DEV_ID_ICH8_IFE,	PCI_ANY_ID, PCI_ANY_ID, 0},
237 	{ 0x8086, E1000_DEV_ID_ICH8_IFE_GT,	PCI_ANY_ID, PCI_ANY_ID, 0},
238 	{ 0x8086, E1000_DEV_ID_ICH8_IFE_G,	PCI_ANY_ID, PCI_ANY_ID, 0},
239 	{ 0x8086, E1000_DEV_ID_ICH8_IGP_M,	PCI_ANY_ID, PCI_ANY_ID, 0},
240 
241 	{ 0x8086, 0x101A, PCI_ANY_ID, PCI_ANY_ID, 0},
242 	{ 0x8086, 0x1014, PCI_ANY_ID, PCI_ANY_ID, 0},
243 	/* required last entry */
244 	{ 0, 0, 0, 0, 0}
245 };
246 
247 /*********************************************************************
248  *  Table of branding strings for all supported NICs.
249  *********************************************************************/
250 
251 static const char *em_strings[] = {
252 	"Intel(R) PRO/1000 Network Connection"
253 };
254 
255 /*********************************************************************
256  *  Function prototypes
257  *********************************************************************/
258 static int	em_probe(device_t);
259 static int	em_attach(device_t);
260 static int	em_detach(device_t);
261 static int	em_shutdown(device_t);
262 static void	em_intr(void *);
263 static int	em_suspend(device_t);
264 static int	em_resume(device_t);
265 static void	em_start(struct ifnet *);
266 static int	em_ioctl(struct ifnet *, u_long, caddr_t, struct ucred *);
267 static void	em_watchdog(struct ifnet *);
268 static void	em_init(void *);
269 static void	em_stop(void *);
270 static void	em_media_status(struct ifnet *, struct ifmediareq *);
271 static int	em_media_change(struct ifnet *);
272 static void	em_identify_hardware(struct adapter *);
273 static int	em_allocate_pci_resources(device_t);
274 static void	em_free_pci_resources(device_t);
275 static void	em_local_timer(void *);
276 static int	em_hardware_init(struct adapter *);
277 static void	em_setup_interface(device_t, struct adapter *);
278 static int	em_setup_transmit_structures(struct adapter *);
279 static void	em_initialize_transmit_unit(struct adapter *);
280 static int	em_setup_receive_structures(struct adapter *);
281 static void	em_initialize_receive_unit(struct adapter *);
282 static void	em_enable_intr(struct adapter *);
283 static void	em_disable_intr(struct adapter *);
284 static void	em_free_transmit_structures(struct adapter *);
285 static void	em_free_receive_structures(struct adapter *);
286 static void	em_update_stats_counters(struct adapter *);
287 static void	em_txeof(struct adapter *);
288 static int	em_allocate_receive_structures(struct adapter *);
289 static void	em_rxeof(struct adapter *, int);
290 static void	em_receive_checksum(struct adapter *, struct em_rx_desc *,
291 				    struct mbuf *);
292 static void	em_transmit_checksum_setup(struct adapter *, struct mbuf *,
293 					   uint32_t *, uint32_t *);
294 static void	em_set_promisc(struct adapter *);
295 static void	em_disable_promisc(struct adapter *);
296 static void	em_set_multi(struct adapter *);
297 static void	em_print_hw_stats(struct adapter *);
298 static void	em_update_link_status(struct adapter *);
299 static int	em_get_buf(int i, struct adapter *, struct mbuf *, int how);
300 static void	em_enable_vlans(struct adapter *);
301 static void	em_disable_vlans(struct adapter *);
302 static int	em_encap(struct adapter *, struct mbuf *);
303 static void	em_smartspeed(struct adapter *);
304 static int	em_82547_fifo_workaround(struct adapter *, int);
305 static void	em_82547_update_fifo_head(struct adapter *, int);
306 static int	em_82547_tx_fifo_reset(struct adapter *);
307 static void	em_82547_move_tail(void *);
308 static void	em_82547_move_tail_serialized(struct adapter *);
309 static int	em_dma_malloc(struct adapter *, bus_size_t,
310 			      struct em_dma_alloc *);
311 static void	em_dma_free(struct adapter *, struct em_dma_alloc *);
312 static void	em_print_debug_info(struct adapter *);
313 static int	em_is_valid_ether_addr(uint8_t *);
314 static int	em_sysctl_stats(SYSCTL_HANDLER_ARGS);
315 static int	em_sysctl_debug_info(SYSCTL_HANDLER_ARGS);
316 static uint32_t	em_fill_descriptors(bus_addr_t address, uint32_t length,
317 				   PDESC_ARRAY desc_array);
318 static int	em_sysctl_int_delay(SYSCTL_HANDLER_ARGS);
319 static int	em_sysctl_int_throttle(SYSCTL_HANDLER_ARGS);
320 static void	em_add_int_delay_sysctl(struct adapter *, const char *,
321 					const char *,
322 					struct em_int_delay_info *, int, int);
323 
324 /*********************************************************************
325  *  FreeBSD Device Interface Entry Points
326  *********************************************************************/
327 
328 static device_method_t em_methods[] = {
329 	/* Device interface */
330 	DEVMETHOD(device_probe, em_probe),
331 	DEVMETHOD(device_attach, em_attach),
332 	DEVMETHOD(device_detach, em_detach),
333 	DEVMETHOD(device_shutdown, em_shutdown),
334 	DEVMETHOD(device_suspend, em_suspend),
335 	DEVMETHOD(device_resume, em_resume),
336 	{0, 0}
337 };
338 
339 static driver_t em_driver = {
340 	"em", em_methods, sizeof(struct adapter),
341 };
342 
343 static devclass_t em_devclass;
344 
345 DECLARE_DUMMY_MODULE(if_em);
346 DRIVER_MODULE(if_em, pci, em_driver, em_devclass, 0, 0);
347 
348 /*********************************************************************
349  *  Tunable default values.
350  *********************************************************************/
351 
352 #define E1000_TICKS_TO_USECS(ticks)	((1024 * (ticks) + 500) / 1000)
353 #define E1000_USECS_TO_TICKS(usecs)	((1000 * (usecs) + 512) / 1024)
354 
355 static int em_tx_int_delay_dflt = E1000_TICKS_TO_USECS(EM_TIDV);
356 static int em_rx_int_delay_dflt = E1000_TICKS_TO_USECS(EM_RDTR);
357 static int em_tx_abs_int_delay_dflt = E1000_TICKS_TO_USECS(EM_TADV);
358 static int em_rx_abs_int_delay_dflt = E1000_TICKS_TO_USECS(EM_RADV);
359 static int em_int_throttle_ceil = 10000;
360 static int em_rxd = EM_DEFAULT_RXD;
361 static int em_txd = EM_DEFAULT_TXD;
362 static int em_smart_pwr_down = FALSE;
363 
364 TUNABLE_INT("hw.em.tx_int_delay", &em_tx_int_delay_dflt);
365 TUNABLE_INT("hw.em.rx_int_delay", &em_rx_int_delay_dflt);
366 TUNABLE_INT("hw.em.tx_abs_int_delay", &em_tx_abs_int_delay_dflt);
367 TUNABLE_INT("hw.em.rx_abs_int_delay", &em_rx_abs_int_delay_dflt);
368 TUNABLE_INT("hw.em.int_throttle_ceil", &em_int_throttle_ceil);
369 TUNABLE_INT("hw.em.rxd", &em_rxd);
370 TUNABLE_INT("hw.em.txd", &em_txd);
371 TUNABLE_INT("hw.em.smart_pwr_down", &em_smart_pwr_down);
372 
373 /*
374  * Kernel trace for characterization of operations
375  */
376 #if !defined(KTR_IF_EM)
377 #define KTR_IF_EM	KTR_ALL
378 #endif
379 KTR_INFO_MASTER(if_em);
380 KTR_INFO(KTR_IF_EM, if_em, intr_beg, 0, "intr begin", 0);
381 KTR_INFO(KTR_IF_EM, if_em, intr_end, 1, "intr end", 0);
382 #ifdef DEVICE_POLLING
383 KTR_INFO(KTR_IF_EM, if_em, poll_beg, 2, "poll begin", 0);
384 KTR_INFO(KTR_IF_EM, if_em, poll_end, 3, "poll end", 0);
385 #endif
386 KTR_INFO(KTR_IF_EM, if_em, pkt_receive, 4, "rx packet", 0);
387 KTR_INFO(KTR_IF_EM, if_em, pkt_txqueue, 5, "tx packet", 0);
388 KTR_INFO(KTR_IF_EM, if_em, pkt_txclean, 6, "tx clean", 0);
389 #define logif(name)	KTR_LOG(if_em_ ## name)
390 
391 /*********************************************************************
392  *  Device identification routine
393  *
394  *  em_probe determines if the driver should be loaded on
395  *  adapter based on PCI vendor/device id of the adapter.
396  *
397  *  return 0 on success, positive on failure
398  *********************************************************************/
399 
400 static int
401 em_probe(device_t dev)
402 {
403 	em_vendor_info_t *ent;
404 
405 	uint16_t pci_vendor_id = 0;
406 	uint16_t pci_device_id = 0;
407 	uint16_t pci_subvendor_id = 0;
408 	uint16_t pci_subdevice_id = 0;
409 	char adapter_name[60];
410 
411 	INIT_DEBUGOUT("em_probe: begin");
412 
413 	pci_vendor_id = pci_get_vendor(dev);
414 	if (pci_vendor_id != EM_VENDOR_ID)
415 		return (ENXIO);
416 
417 	pci_device_id = pci_get_device(dev);
418 	pci_subvendor_id = pci_get_subvendor(dev);
419 	pci_subdevice_id = pci_get_subdevice(dev);
420 
421 	ent = em_vendor_info_array;
422 	while (ent->vendor_id != 0) {
423 		if ((pci_vendor_id == ent->vendor_id) &&
424 		    (pci_device_id == ent->device_id) &&
425 
426 		    ((pci_subvendor_id == ent->subvendor_id) ||
427 		     (ent->subvendor_id == PCI_ANY_ID)) &&
428 
429 		    ((pci_subdevice_id == ent->subdevice_id) ||
430 		     (ent->subdevice_id == PCI_ANY_ID))) {
431 			ksnprintf(adapter_name, sizeof(adapter_name),
432 				 "%s, Version - %s",  em_strings[ent->index],
433 				 em_driver_version);
434 			device_set_desc_copy(dev, adapter_name);
435 			return (0);
436 		}
437 		ent++;
438 	}
439 
440 	return (ENXIO);
441 }
442 
443 /*********************************************************************
444  *  Device initialization routine
445  *
446  *  The attach entry point is called when the driver is being loaded.
447  *  This routine identifies the type of hardware, allocates all resources
448  *  and initializes the hardware.
449  *
450  *  return 0 on success, positive on failure
451  *********************************************************************/
452 
453 static int
454 em_attach(device_t dev)
455 {
456 	struct adapter *adapter;
457 	int tsize, rsize;
458 	int error = 0;
459 
460 	INIT_DEBUGOUT("em_attach: begin");
461 
462 	adapter = device_get_softc(dev);
463 
464 	callout_init(&adapter->timer);
465 	callout_init(&adapter->tx_fifo_timer);
466 
467 	adapter->dev = dev;
468 	adapter->osdep.dev = dev;
469 
470 	/* SYSCTL stuff */
471 	sysctl_ctx_init(&adapter->sysctl_ctx);
472 	adapter->sysctl_tree = SYSCTL_ADD_NODE(&adapter->sysctl_ctx,
473 					       SYSCTL_STATIC_CHILDREN(_hw),
474 					       OID_AUTO,
475 					       device_get_nameunit(dev),
476 					       CTLFLAG_RD,
477 					       0, "");
478 
479 	if (adapter->sysctl_tree == NULL) {
480 		device_printf(dev, "Unable to create sysctl tree\n");
481 		return EIO;
482 	}
483 
484 	SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
485 			SYSCTL_CHILDREN(adapter->sysctl_tree),
486 			OID_AUTO, "debug_info", CTLTYPE_INT|CTLFLAG_RW,
487 			(void *)adapter, 0,
488 			em_sysctl_debug_info, "I", "Debug Information");
489 
490 	SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
491 			SYSCTL_CHILDREN(adapter->sysctl_tree),
492 			OID_AUTO, "stats", CTLTYPE_INT|CTLFLAG_RW,
493 			(void *)adapter, 0,
494 			em_sysctl_stats, "I", "Statistics");
495 
496 	/* Determine hardware revision */
497 	em_identify_hardware(adapter);
498 
499 	/* Set up some sysctls for the tunable interrupt delays */
500 	em_add_int_delay_sysctl(adapter, "rx_int_delay",
501 				"receive interrupt delay in usecs",
502 				&adapter->rx_int_delay,
503 				E1000_REG_OFFSET(&adapter->hw, RDTR),
504 				em_rx_int_delay_dflt);
505 	em_add_int_delay_sysctl(adapter, "tx_int_delay",
506 				"transmit interrupt delay in usecs",
507 				&adapter->tx_int_delay,
508 				E1000_REG_OFFSET(&adapter->hw, TIDV),
509 				em_tx_int_delay_dflt);
510 	if (adapter->hw.mac_type >= em_82540) {
511 		em_add_int_delay_sysctl(adapter, "rx_abs_int_delay",
512 					"receive interrupt delay limit in usecs",
513 					&adapter->rx_abs_int_delay,
514 					E1000_REG_OFFSET(&adapter->hw, RADV),
515 					em_rx_abs_int_delay_dflt);
516 		em_add_int_delay_sysctl(adapter, "tx_abs_int_delay",
517 					"transmit interrupt delay limit in usecs",
518 					&adapter->tx_abs_int_delay,
519 					E1000_REG_OFFSET(&adapter->hw, TADV),
520 					em_tx_abs_int_delay_dflt);
521 		SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
522 			SYSCTL_CHILDREN(adapter->sysctl_tree),
523 			OID_AUTO, "int_throttle_ceil", CTLTYPE_INT|CTLFLAG_RW,
524 			adapter, 0, em_sysctl_int_throttle, "I", NULL);
525 	}
526 
527 	/*
528 	 * Validate number of transmit and receive descriptors. It
529 	 * must not exceed hardware maximum, and must be multiple
530 	 * of EM_DBA_ALIGN.
531 	 */
532 	if (((em_txd * sizeof(struct em_tx_desc)) % EM_DBA_ALIGN) != 0 ||
533 	    (adapter->hw.mac_type >= em_82544 && em_txd > EM_MAX_TXD) ||
534 	    (adapter->hw.mac_type < em_82544 && em_txd > EM_MAX_TXD_82543) ||
535 	    (em_txd < EM_MIN_TXD)) {
536 		device_printf(dev, "Using %d TX descriptors instead of %d!\n",
537 			      EM_DEFAULT_TXD, em_txd);
538 		adapter->num_tx_desc = EM_DEFAULT_TXD;
539 	} else {
540 		adapter->num_tx_desc = em_txd;
541 	}
542 
543 	if (((em_rxd * sizeof(struct em_rx_desc)) % EM_DBA_ALIGN) != 0 ||
544 	    (adapter->hw.mac_type >= em_82544 && em_rxd > EM_MAX_RXD) ||
545 	    (adapter->hw.mac_type < em_82544 && em_rxd > EM_MAX_RXD_82543) ||
546 	    (em_rxd < EM_MIN_RXD)) {
547 		device_printf(dev, "Using %d RX descriptors instead of %d!\n",
548 			      EM_DEFAULT_RXD, em_rxd);
549 		adapter->num_rx_desc = EM_DEFAULT_RXD;
550 	} else {
551 		adapter->num_rx_desc = em_rxd;
552 	}
553 
554 	SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(adapter->sysctl_tree), OID_AUTO, "rxd",
555 		       CTLFLAG_RD, &adapter->num_rx_desc, 0, NULL);
556 	SYSCTL_ADD_INT(NULL, SYSCTL_CHILDREN(adapter->sysctl_tree), OID_AUTO, "txd",
557 		       CTLFLAG_RD, &adapter->num_tx_desc, 0, NULL);
558 
559 	adapter->hw.autoneg = DO_AUTO_NEG;
560 	adapter->hw.wait_autoneg_complete = WAIT_FOR_AUTO_NEG_DEFAULT;
561 	adapter->hw.autoneg_advertised = AUTONEG_ADV_DEFAULT;
562 	adapter->hw.tbi_compatibility_en = TRUE;
563 	adapter->rx_buffer_len = EM_RXBUFFER_2048;
564 
565 	adapter->hw.phy_init_script = 1;
566 	adapter->hw.phy_reset_disable = FALSE;
567 
568 #ifndef EM_MASTER_SLAVE
569 	adapter->hw.master_slave = em_ms_hw_default;
570 #else
571 	adapter->hw.master_slave = EM_MASTER_SLAVE;
572 #endif
573 
574 	/*
575 	 * Set the max frame size assuming standard ethernet
576 	 * sized frames.
577 	 */
578 	adapter->hw.max_frame_size = ETHERMTU + ETHER_HDR_LEN + ETHER_CRC_LEN;
579 
580 	adapter->hw.min_frame_size =
581 	    MINIMUM_ETHERNET_PACKET_SIZE + ETHER_CRC_LEN;
582 
583 	/*
584 	 * This controls when hardware reports transmit completion
585 	 * status.
586 	 */
587 	adapter->hw.report_tx_early = 1;
588 
589 	error = em_allocate_pci_resources(dev);
590 	if (error)
591 		goto fail;
592 
593 	/* Initialize eeprom parameters */
594 	em_init_eeprom_params(&adapter->hw);
595 
596 	tsize = roundup2(adapter->num_tx_desc * sizeof(struct em_tx_desc),
597 			 EM_DBA_ALIGN);
598 
599 	/* Allocate Transmit Descriptor ring */
600 	error = em_dma_malloc(adapter, tsize, &adapter->txdma);
601 	if (error) {
602 		device_printf(dev, "Unable to allocate TxDescriptor memory\n");
603 		goto fail;
604 	}
605 	adapter->tx_desc_base = (struct em_tx_desc *)adapter->txdma.dma_vaddr;
606 
607 	rsize = roundup2(adapter->num_rx_desc * sizeof(struct em_rx_desc),
608 			 EM_DBA_ALIGN);
609 
610 	/* Allocate Receive Descriptor ring */
611 	error = em_dma_malloc(adapter, rsize, &adapter->rxdma);
612 	if (error) {
613 		device_printf(dev, "Unable to allocate rx_desc memory\n");
614 		goto fail;
615 	}
616 	adapter->rx_desc_base = (struct em_rx_desc *)adapter->rxdma.dma_vaddr;
617 
618 	/* Initialize the hardware */
619 	if (em_hardware_init(adapter)) {
620 		device_printf(dev, "Unable to initialize the hardware\n");
621 		error = EIO;
622 		goto fail;
623 	}
624 
625 	/* Copy the permanent MAC address out of the EEPROM */
626 	if (em_read_mac_addr(&adapter->hw) < 0) {
627 		device_printf(dev,
628 			      "EEPROM read error while reading MAC address\n");
629 		error = EIO;
630 		goto fail;
631 	}
632 
633 	if (!em_is_valid_ether_addr(adapter->hw.mac_addr)) {
634 		device_printf(dev, "Invalid MAC address\n");
635 		error = EIO;
636 		goto fail;
637 	}
638 
639 	/* Setup OS specific network interface */
640 	em_setup_interface(dev, adapter);
641 
642 	/* Initialize statistics */
643 	em_clear_hw_cntrs(&adapter->hw);
644 	em_update_stats_counters(adapter);
645 	adapter->hw.get_link_status = 1;
646 	em_update_link_status(adapter);
647 
648 	/* Indicate SOL/IDER usage */
649 	if (em_check_phy_reset_block(&adapter->hw)) {
650 		device_printf(dev, "PHY reset is blocked due to "
651 			      "SOL/IDER session.\n");
652 	}
653 
654 	/* Identify 82544 on PCIX */
655 	em_get_bus_info(&adapter->hw);
656 	if (adapter->hw.bus_type == em_bus_type_pcix &&
657 	    adapter->hw.mac_type == em_82544)
658 		adapter->pcix_82544 = TRUE;
659 	else
660 		adapter->pcix_82544 = FALSE;
661 
662 	error = bus_setup_intr(dev, adapter->res_interrupt, INTR_NETSAFE,
663 			   em_intr, adapter,
664 			   &adapter->int_handler_tag,
665 			   adapter->interface_data.ac_if.if_serializer);
666 	if (error) {
667 		device_printf(dev, "Error registering interrupt handler!\n");
668 		ether_ifdetach(&adapter->interface_data.ac_if);
669 		goto fail;
670 	}
671 
672 	INIT_DEBUGOUT("em_attach: end");
673 	return(0);
674 
675 fail:
676 	em_detach(dev);
677 	return(error);
678 }
679 
680 /*********************************************************************
681  *  Device removal routine
682  *
683  *  The detach entry point is called when the driver is being removed.
684  *  This routine stops the adapter and deallocates all the resources
685  *  that were allocated for driver operation.
686  *
687  *  return 0 on success, positive on failure
688  *********************************************************************/
689 
690 static int
691 em_detach(device_t dev)
692 {
693 	struct adapter *adapter = device_get_softc(dev);
694 
695 	INIT_DEBUGOUT("em_detach: begin");
696 
697 	if (device_is_attached(dev)) {
698 		struct ifnet *ifp = &adapter->interface_data.ac_if;
699 
700 		lwkt_serialize_enter(ifp->if_serializer);
701 		adapter->in_detach = 1;
702 		em_stop(adapter);
703 		em_phy_hw_reset(&adapter->hw);
704 		bus_teardown_intr(dev, adapter->res_interrupt,
705 				  adapter->int_handler_tag);
706 		lwkt_serialize_exit(ifp->if_serializer);
707 
708 		ether_ifdetach(ifp);
709 	}
710 	bus_generic_detach(dev);
711 
712 	em_free_pci_resources(dev);
713 
714 	/* Free Transmit Descriptor ring */
715 	if (adapter->tx_desc_base != NULL) {
716 		em_dma_free(adapter, &adapter->txdma);
717 		adapter->tx_desc_base = NULL;
718 	}
719 
720 	/* Free Receive Descriptor ring */
721 	if (adapter->rx_desc_base != NULL) {
722 		em_dma_free(adapter, &adapter->rxdma);
723 		adapter->rx_desc_base = NULL;
724 	}
725 
726 	/* Free sysctl tree */
727 	if (adapter->sysctl_tree != NULL) {
728 		adapter->sysctl_tree = NULL;
729 		sysctl_ctx_free(&adapter->sysctl_ctx);
730 	}
731 
732 	return (0);
733 }
734 
735 /*********************************************************************
736  *
737  *  Shutdown entry point
738  *
739  **********************************************************************/
740 
741 static int
742 em_shutdown(device_t dev)
743 {
744 	struct adapter *adapter = device_get_softc(dev);
745 	struct ifnet *ifp = &adapter->interface_data.ac_if;
746 
747 	lwkt_serialize_enter(ifp->if_serializer);
748 	em_stop(adapter);
749 	lwkt_serialize_exit(ifp->if_serializer);
750 
751 	return (0);
752 }
753 
754 /*
755  * Suspend/resume device methods.
756  */
757 static int
758 em_suspend(device_t dev)
759 {
760 	struct adapter *adapter = device_get_softc(dev);
761 	struct ifnet *ifp = &adapter->interface_data.ac_if;
762 
763 	lwkt_serialize_enter(ifp->if_serializer);
764 	em_stop(adapter);
765 	lwkt_serialize_exit(ifp->if_serializer);
766 	return (0);
767 }
768 
769 static int
770 em_resume(device_t dev)
771 {
772 	struct adapter *adapter = device_get_softc(dev);
773 	struct ifnet *ifp = &adapter->interface_data.ac_if;
774 
775 	lwkt_serialize_enter(ifp->if_serializer);
776 	ifp->if_flags &= ~IFF_RUNNING;
777 	em_init(adapter);
778 	if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) == (IFF_UP | IFF_RUNNING))
779 		em_start(ifp);
780 	lwkt_serialize_exit(ifp->if_serializer);
781 
782 	return bus_generic_resume(dev);
783 }
784 
785 /*********************************************************************
786  *  Transmit entry point
787  *
788  *  em_start is called by the stack to initiate a transmit.
789  *  The driver will remain in this routine as long as there are
790  *  packets to transmit and transmit resources are available.
791  *  In case resources are not available stack is notified and
792  *  the packet is requeued.
793  **********************************************************************/
794 
795 static void
796 em_start(struct ifnet *ifp)
797 {
798 	struct mbuf *m_head;
799 	struct adapter *adapter = ifp->if_softc;
800 
801 	ASSERT_SERIALIZED(ifp->if_serializer);
802 
803 	if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
804 		return;
805 	if (!adapter->link_active)
806 		return;
807 	while (!ifq_is_empty(&ifp->if_snd)) {
808 		m_head = ifq_poll(&ifp->if_snd);
809 
810 		if (m_head == NULL)
811 			break;
812 
813 		logif(pkt_txqueue);
814 		if (em_encap(adapter, m_head)) {
815 			ifp->if_flags |= IFF_OACTIVE;
816 			break;
817 		}
818 		ifq_dequeue(&ifp->if_snd, m_head);
819 
820 		/* Send a copy of the frame to the BPF listener */
821 		BPF_MTAP(ifp, m_head);
822 
823 		/* Set timeout in case hardware has problems transmitting. */
824 		ifp->if_timer = EM_TX_TIMEOUT;
825 	}
826 }
827 
828 /*********************************************************************
829  *  Ioctl entry point
830  *
831  *  em_ioctl is called when the user wants to configure the
832  *  interface.
833  *
834  *  return 0 on success, positive on failure
835  **********************************************************************/
836 
837 static int
838 em_ioctl(struct ifnet *ifp, u_long command, caddr_t data, struct ucred *cr)
839 {
840 	int max_frame_size, mask, error = 0, reinit = 0;
841 	struct ifreq *ifr = (struct ifreq *) data;
842 	struct adapter *adapter = ifp->if_softc;
843 	uint16_t eeprom_data = 0;
844 
845 	ASSERT_SERIALIZED(ifp->if_serializer);
846 
847 	if (adapter->in_detach)
848 		return 0;
849 
850 	switch (command) {
851 	case SIOCSIFMTU:
852 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOCSIFMTU (Set Interface MTU)");
853 		switch (adapter->hw.mac_type) {
854 		case em_82573:
855 			/*
856 			 * 82573 only supports jumbo frames
857 			 * if ASPM is disabled.
858 			 */
859 			em_read_eeprom(&adapter->hw, EEPROM_INIT_3GIO_3,
860 			    1, &eeprom_data);
861 			if (eeprom_data & EEPROM_WORD1A_ASPM_MASK) {
862 				max_frame_size = ETHER_MAX_LEN;
863 				break;
864 			}
865 			/* Allow Jumbo frames */
866 			/* FALLTHROUGH */
867 		case em_82571:
868 		case em_82572:
869 		case em_80003es2lan:	/* Limit Jumbo Frame size */
870 			max_frame_size = 9234;
871 			break;
872 		case em_ich8lan:
873 			/* ICH8 does not support jumbo frames */
874 			max_frame_size = ETHER_MAX_LEN;
875 			break;
876 		default:
877 			max_frame_size = MAX_JUMBO_FRAME_SIZE;
878 			break;
879 		}
880 		if (ifr->ifr_mtu >
881 			max_frame_size - ETHER_HDR_LEN - ETHER_CRC_LEN) {
882 			error = EINVAL;
883 		} else {
884 			ifp->if_mtu = ifr->ifr_mtu;
885 			adapter->hw.max_frame_size =
886 			ifp->if_mtu + ETHER_HDR_LEN + ETHER_CRC_LEN;
887 			ifp->if_flags &= ~IFF_RUNNING;
888 			em_init(adapter);
889 		}
890 		break;
891 	case SIOCSIFFLAGS:
892 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOCSIFFLAGS "
893 			       "(Set Interface Flags)");
894 		if (ifp->if_flags & IFF_UP) {
895 			if (!(ifp->if_flags & IFF_RUNNING)) {
896 				em_init(adapter);
897 			} else if ((ifp->if_flags ^ adapter->if_flags) &
898 				   IFF_PROMISC) {
899 				em_disable_promisc(adapter);
900 				em_set_promisc(adapter);
901 			}
902 		} else {
903 			if (ifp->if_flags & IFF_RUNNING)
904 				em_stop(adapter);
905 		}
906 		adapter->if_flags = ifp->if_flags;
907 		break;
908 	case SIOCADDMULTI:
909 	case SIOCDELMULTI:
910 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOC(ADD|DEL)MULTI");
911 		if (ifp->if_flags & IFF_RUNNING) {
912 			em_disable_intr(adapter);
913 			em_set_multi(adapter);
914 			if (adapter->hw.mac_type == em_82542_rev2_0)
915 				em_initialize_receive_unit(adapter);
916 #ifdef DEVICE_POLLING
917 			/* Do not enable interrupt if polling(4) is enabled */
918 			if ((ifp->if_flags & IFF_POLLING) == 0)
919 #endif
920 			em_enable_intr(adapter);
921 		}
922 		break;
923 	case SIOCSIFMEDIA:
924 		/* Check SOL/IDER usage */
925 		if (em_check_phy_reset_block(&adapter->hw)) {
926 			if_printf(ifp, "Media change is blocked due to "
927 				  "SOL/IDER session.\n");
928 			break;
929 		}
930 		/* FALLTHROUGH */
931 	case SIOCGIFMEDIA:
932 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOCxIFMEDIA "
933 			       "(Get/Set Interface Media)");
934 		error = ifmedia_ioctl(ifp, ifr, &adapter->media, command);
935 		break;
936 	case SIOCSIFCAP:
937 		IOCTL_DEBUGOUT("ioctl rcv'd: SIOCSIFCAP (Set Capabilities)");
938 		mask = ifr->ifr_reqcap ^ ifp->if_capenable;
939 		if (mask & IFCAP_HWCSUM) {
940 			ifp->if_capenable ^= IFCAP_HWCSUM;
941 			reinit = 1;
942 		}
943 		if (mask & IFCAP_VLAN_HWTAGGING) {
944 			ifp->if_capenable ^= IFCAP_VLAN_HWTAGGING;
945 			reinit = 1;
946 		}
947 		if (reinit && (ifp->if_flags & IFF_RUNNING)) {
948 			ifp->if_flags &= ~IFF_RUNNING;
949 			em_init(adapter);
950 		}
951 		break;
952 	default:
953 		error = ether_ioctl(ifp, command, data);
954 		break;
955 	}
956 
957 	return (error);
958 }
959 
960 /*********************************************************************
961  *  Watchdog entry point
962  *
963  *  This routine is called whenever hardware quits transmitting.
964  *
965  **********************************************************************/
966 
967 static void
968 em_watchdog(struct ifnet *ifp)
969 {
970 	struct adapter *adapter = ifp->if_softc;
971 
972 	/*
973 	 * If we are in this routine because of pause frames, then
974 	 * don't reset the hardware.
975 	 */
976 	if (E1000_READ_REG(&adapter->hw, STATUS) & E1000_STATUS_TXOFF) {
977 		ifp->if_timer = EM_TX_TIMEOUT;
978 		return;
979 	}
980 
981 	if (em_check_for_link(&adapter->hw) == 0)
982 		if_printf(ifp, "watchdog timeout -- resetting\n");
983 
984 	ifp->if_flags &= ~IFF_RUNNING;
985 	em_init(adapter);
986 
987 	adapter->watchdog_timeouts++;
988 }
989 
990 /*********************************************************************
991  *  Init entry point
992  *
993  *  This routine is used in two ways. It is used by the stack as
994  *  init entry point in network interface structure. It is also used
995  *  by the driver as a hw/sw initialization routine to get to a
996  *  consistent state.
997  *
998  *  return 0 on success, positive on failure
999  **********************************************************************/
1000 
1001 static void
1002 em_init(void *arg)
1003 {
1004 	struct adapter *adapter = arg;
1005 	uint32_t pba;
1006 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1007 
1008 	ASSERT_SERIALIZED(ifp->if_serializer);
1009 
1010 	INIT_DEBUGOUT("em_init: begin");
1011 
1012 	if (ifp->if_flags & IFF_RUNNING)
1013 		return;
1014 
1015 	em_stop(adapter);
1016 
1017 	/*
1018 	 * Packet Buffer Allocation (PBA)
1019 	 * Writing PBA sets the receive portion of the buffer
1020 	 * the remainder is used for the transmit buffer.
1021 	 *
1022 	 * Devices before the 82547 had a Packet Buffer of 64K.
1023 	 *   Default allocation: PBA=48K for Rx, leaving 16K for Tx.
1024 	 * After the 82547 the buffer was reduced to 40K.
1025 	 *   Default allocation: PBA=30K for Rx, leaving 10K for Tx.
1026 	 *   Note: default does not leave enough room for Jumbo Frame >10k.
1027 	 */
1028 	switch (adapter->hw.mac_type) {
1029 	case em_82547:
1030 	case em_82547_rev_2: /* 82547: Total Packet Buffer is 40K */
1031 		if (adapter->hw.max_frame_size > EM_RXBUFFER_8192)
1032 			pba = E1000_PBA_22K; /* 22K for Rx, 18K for Tx */
1033 		else
1034 			pba = E1000_PBA_30K; /* 30K for Rx, 10K for Tx */
1035 
1036 		adapter->tx_fifo_head = 0;
1037 		adapter->tx_head_addr = pba << EM_TX_HEAD_ADDR_SHIFT;
1038 		adapter->tx_fifo_size =
1039 			(E1000_PBA_40K - pba) << EM_PBA_BYTES_SHIFT;
1040 		break;
1041 	/* Total Packet Buffer on these is 48K */
1042 	case em_82571:
1043 	case em_82572:
1044 	case em_80003es2lan:
1045 		pba = E1000_PBA_32K; /* 32K for Rx, 16K for Tx */
1046 		break;
1047 	case em_82573: /* 82573: Total Packet Buffer is 32K */
1048 		pba = E1000_PBA_12K; /* 12K for Rx, 20K for Tx */
1049 		break;
1050 	case em_ich8lan:
1051 		pba = E1000_PBA_8K;
1052 		break;
1053 	default:
1054 		/* Devices before 82547 had a Packet Buffer of 64K.   */
1055 		if(adapter->hw.max_frame_size > EM_RXBUFFER_8192)
1056 			pba = E1000_PBA_40K; /* 40K for Rx, 24K for Tx */
1057 		else
1058 			pba = E1000_PBA_48K; /* 48K for Rx, 16K for Tx */
1059 	}
1060 
1061 	INIT_DEBUGOUT1("em_init: pba=%dK",pba);
1062 	E1000_WRITE_REG(&adapter->hw, PBA, pba);
1063 
1064 	/* Get the latest mac address, User can use a LAA */
1065 	bcopy(adapter->interface_data.ac_enaddr, adapter->hw.mac_addr,
1066 	      ETHER_ADDR_LEN);
1067 
1068 	/* Initialize the hardware */
1069 	if (em_hardware_init(adapter)) {
1070 		if_printf(ifp, "Unable to initialize the hardware\n");
1071 		return;
1072 	}
1073 	em_update_link_status(adapter);
1074 
1075 	if (ifp->if_capenable & IFCAP_VLAN_HWTAGGING)
1076 		em_enable_vlans(adapter);
1077 
1078 	/* Set hardware offload abilities */
1079 	if (adapter->hw.mac_type >= em_82543) {
1080 		if (ifp->if_capenable & IFCAP_TXCSUM)
1081 			ifp->if_hwassist = EM_CHECKSUM_FEATURES;
1082 		else
1083 			ifp->if_hwassist = 0;
1084 	}
1085 
1086 	/* Prepare transmit descriptors and buffers */
1087 	if (em_setup_transmit_structures(adapter)) {
1088 		if_printf(ifp, "Could not setup transmit structures\n");
1089 		em_stop(adapter);
1090 		return;
1091 	}
1092 	em_initialize_transmit_unit(adapter);
1093 
1094 	/* Setup Multicast table */
1095 	em_set_multi(adapter);
1096 
1097 	/* Prepare receive descriptors and buffers */
1098 	if (em_setup_receive_structures(adapter)) {
1099 		if_printf(ifp, "Could not setup receive structures\n");
1100 		em_stop(adapter);
1101 		return;
1102 	}
1103 	em_initialize_receive_unit(adapter);
1104 
1105 	/* Don't lose promiscuous settings */
1106 	em_set_promisc(adapter);
1107 
1108 	ifp->if_flags |= IFF_RUNNING;
1109 	ifp->if_flags &= ~IFF_OACTIVE;
1110 
1111 	callout_reset(&adapter->timer, hz, em_local_timer, adapter);
1112 	em_clear_hw_cntrs(&adapter->hw);
1113 
1114 #ifdef DEVICE_POLLING
1115 	/* Do not enable interrupt if polling(4) is enabled */
1116 	if (ifp->if_flags & IFF_POLLING)
1117 		em_disable_intr(adapter);
1118 	else
1119 #endif
1120 	em_enable_intr(adapter);
1121 
1122 	/* Don't reset the phy next time init gets called */
1123 	adapter->hw.phy_reset_disable = TRUE;
1124 }
1125 
1126 #ifdef DEVICE_POLLING
1127 
1128 static void
1129 em_poll(struct ifnet *ifp, enum poll_cmd cmd, int count)
1130 {
1131 	struct adapter *adapter = ifp->if_softc;
1132 	uint32_t reg_icr;
1133 
1134 	logif(poll_beg);
1135 
1136 	ASSERT_SERIALIZED(ifp->if_serializer);
1137 
1138 	switch(cmd) {
1139 	case POLL_REGISTER:
1140 		em_disable_intr(adapter);
1141 		break;
1142 	case POLL_DEREGISTER:
1143 		em_enable_intr(adapter);
1144 		break;
1145 	case POLL_AND_CHECK_STATUS:
1146 		reg_icr = E1000_READ_REG(&adapter->hw, ICR);
1147 		if (reg_icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC)) {
1148 			callout_stop(&adapter->timer);
1149 			adapter->hw.get_link_status = 1;
1150 			em_check_for_link(&adapter->hw);
1151 			em_update_link_status(adapter);
1152 			callout_reset(&adapter->timer, hz, em_local_timer,
1153 				      adapter);
1154 		}
1155 		/* fall through */
1156 	case POLL_ONLY:
1157 		if (ifp->if_flags & IFF_RUNNING) {
1158 			em_rxeof(adapter, count);
1159 			em_txeof(adapter);
1160 
1161 			if (!ifq_is_empty(&ifp->if_snd))
1162 				em_start(ifp);
1163 		}
1164 		break;
1165 	}
1166 	logif(poll_end);
1167 }
1168 
1169 #endif /* DEVICE_POLLING */
1170 
1171 /*********************************************************************
1172  *
1173  *  Interrupt Service routine
1174  *
1175  *********************************************************************/
1176 static void
1177 em_intr(void *arg)
1178 {
1179 	uint32_t reg_icr;
1180 	struct ifnet *ifp;
1181 	struct adapter *adapter = arg;
1182 
1183 	ifp = &adapter->interface_data.ac_if;
1184 
1185 	logif(intr_beg);
1186 	ASSERT_SERIALIZED(ifp->if_serializer);
1187 
1188 	reg_icr = E1000_READ_REG(&adapter->hw, ICR);
1189 	if ((adapter->hw.mac_type >= em_82571 &&
1190 	     (reg_icr & E1000_ICR_INT_ASSERTED) == 0) ||
1191 	    reg_icr == 0) {
1192 		logif(intr_end);
1193 		return;
1194 	}
1195 
1196 	/*
1197 	 * XXX: some laptops trigger several spurious interrupts on em(4)
1198 	 * when in the resume cycle. The ICR register reports all-ones
1199 	 * value in this case. Processing such interrupts would lead to
1200 	 * a freeze. I don't know why.
1201 	 */
1202 	if (reg_icr == 0xffffffff) {
1203 		logif(intr_end);
1204 		return;
1205 	}
1206 
1207 	/*
1208 	 * note: do not attempt to improve efficiency by looping.  This
1209 	 * only results in unnecessary piecemeal collection of received
1210 	 * packets and unnecessary piecemeal cleanups of the transmit ring.
1211 	 */
1212 	if (ifp->if_flags & IFF_RUNNING) {
1213 		em_rxeof(adapter, -1);
1214 		em_txeof(adapter);
1215 	}
1216 
1217 	/* Link status change */
1218 	if (reg_icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC)) {
1219 		callout_stop(&adapter->timer);
1220 		adapter->hw.get_link_status = 1;
1221 		em_check_for_link(&adapter->hw);
1222 		em_update_link_status(adapter);
1223 		callout_reset(&adapter->timer, hz, em_local_timer, adapter);
1224 	}
1225 
1226 	if (reg_icr & E1000_ICR_RXO)
1227 		adapter->rx_overruns++;
1228 
1229 	if ((ifp->if_flags & IFF_RUNNING) && !ifq_is_empty(&ifp->if_snd))
1230 		em_start(ifp);
1231 	logif(intr_end);
1232 }
1233 
1234 /*********************************************************************
1235  *
1236  *  Media Ioctl callback
1237  *
1238  *  This routine is called whenever the user queries the status of
1239  *  the interface using ifconfig.
1240  *
1241  **********************************************************************/
1242 static void
1243 em_media_status(struct ifnet *ifp, struct ifmediareq *ifmr)
1244 {
1245 	struct adapter *adapter = ifp->if_softc;
1246 	u_char fiber_type = IFM_1000_SX;
1247 
1248 	INIT_DEBUGOUT("em_media_status: begin");
1249 
1250 	ASSERT_SERIALIZED(ifp->if_serializer);
1251 
1252 	em_check_for_link(&adapter->hw);
1253 	em_update_link_status(adapter);
1254 
1255 	ifmr->ifm_status = IFM_AVALID;
1256 	ifmr->ifm_active = IFM_ETHER;
1257 
1258 	if (!adapter->link_active)
1259 		return;
1260 
1261 	ifmr->ifm_status |= IFM_ACTIVE;
1262 
1263 	if (adapter->hw.media_type == em_media_type_fiber ||
1264 	    adapter->hw.media_type == em_media_type_internal_serdes) {
1265 		if (adapter->hw.mac_type == em_82545)
1266 			fiber_type = IFM_1000_LX;
1267 		ifmr->ifm_active |= fiber_type | IFM_FDX;
1268 	} else {
1269 		switch (adapter->link_speed) {
1270 		case 10:
1271 			ifmr->ifm_active |= IFM_10_T;
1272 			break;
1273 		case 100:
1274 			ifmr->ifm_active |= IFM_100_TX;
1275 			break;
1276 		case 1000:
1277 			ifmr->ifm_active |= IFM_1000_T;
1278 			break;
1279 		}
1280 		if (adapter->link_duplex == FULL_DUPLEX)
1281 			ifmr->ifm_active |= IFM_FDX;
1282 		else
1283 			ifmr->ifm_active |= IFM_HDX;
1284 	}
1285 }
1286 
1287 /*********************************************************************
1288  *
1289  *  Media Ioctl callback
1290  *
1291  *  This routine is called when the user changes speed/duplex using
1292  *  media/mediopt option with ifconfig.
1293  *
1294  **********************************************************************/
1295 static int
1296 em_media_change(struct ifnet *ifp)
1297 {
1298 	struct adapter *adapter = ifp->if_softc;
1299 	struct ifmedia *ifm = &adapter->media;
1300 
1301 	INIT_DEBUGOUT("em_media_change: begin");
1302 
1303 	ASSERT_SERIALIZED(ifp->if_serializer);
1304 
1305 	if (IFM_TYPE(ifm->ifm_media) != IFM_ETHER)
1306 		return (EINVAL);
1307 
1308 	switch (IFM_SUBTYPE(ifm->ifm_media)) {
1309 	case IFM_AUTO:
1310 		adapter->hw.autoneg = DO_AUTO_NEG;
1311 		adapter->hw.autoneg_advertised = AUTONEG_ADV_DEFAULT;
1312 		break;
1313 	case IFM_1000_LX:
1314 	case IFM_1000_SX:
1315 	case IFM_1000_T:
1316 		adapter->hw.autoneg = DO_AUTO_NEG;
1317 		adapter->hw.autoneg_advertised = ADVERTISE_1000_FULL;
1318 		break;
1319 	case IFM_100_TX:
1320 		adapter->hw.autoneg = FALSE;
1321 		adapter->hw.autoneg_advertised = 0;
1322 		if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
1323 			adapter->hw.forced_speed_duplex = em_100_full;
1324 		else
1325 			adapter->hw.forced_speed_duplex = em_100_half;
1326 		break;
1327 	case IFM_10_T:
1328 		adapter->hw.autoneg = FALSE;
1329 		adapter->hw.autoneg_advertised = 0;
1330 		if ((ifm->ifm_media & IFM_GMASK) == IFM_FDX)
1331 			adapter->hw.forced_speed_duplex = em_10_full;
1332 		else
1333 			adapter->hw.forced_speed_duplex = em_10_half;
1334 		break;
1335 	default:
1336 		if_printf(ifp, "Unsupported media type\n");
1337 	}
1338 	/*
1339 	 * As the speed/duplex settings may have changed we need to
1340 	 * reset the PHY.
1341 	 */
1342 	adapter->hw.phy_reset_disable = FALSE;
1343 
1344 	ifp->if_flags &= ~IFF_RUNNING;
1345 	em_init(adapter);
1346 
1347 	return(0);
1348 }
1349 
1350 static void
1351 em_tx_cb(void *arg, bus_dma_segment_t *seg, int nsegs, bus_size_t mapsize,
1352 	 int error)
1353 {
1354 	struct em_q *q = arg;
1355 
1356 	if (error)
1357 		return;
1358 	KASSERT(nsegs <= EM_MAX_SCATTER,
1359 		("Too many DMA segments returned when mapping tx packet"));
1360 	q->nsegs = nsegs;
1361 	bcopy(seg, q->segs, nsegs * sizeof(seg[0]));
1362 }
1363 
1364 /*********************************************************************
1365  *
1366  *  This routine maps the mbufs to tx descriptors.
1367  *
1368  *  return 0 on success, positive on failure
1369  **********************************************************************/
1370 static int
1371 em_encap(struct adapter *adapter, struct mbuf *m_head)
1372 {
1373 	uint32_t txd_upper = 0, txd_lower = 0, txd_used = 0, txd_saved = 0;
1374 	int i, j, error, last = 0;
1375 
1376 	struct ifvlan *ifv = NULL;
1377 	struct em_q q;
1378 	struct em_buffer *tx_buffer = NULL, *tx_buffer_first;
1379 	bus_dmamap_t map;
1380 	struct em_tx_desc *current_tx_desc = NULL;
1381 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1382 
1383 	/*
1384 	 * Force a cleanup if number of TX descriptors
1385 	 * available hits the threshold
1386 	 */
1387 	if (adapter->num_tx_desc_avail <= EM_TX_CLEANUP_THRESHOLD) {
1388 		em_txeof(adapter);
1389 		if (adapter->num_tx_desc_avail <= EM_TX_CLEANUP_THRESHOLD) {
1390 			adapter->no_tx_desc_avail1++;
1391 			return (ENOBUFS);
1392 		}
1393 	}
1394 
1395 	/*
1396 	 * Capture the first descriptor index, this descriptor will have
1397 	 * the index of the EOP which is the only one that now gets a
1398 	 * DONE bit writeback.
1399 	 */
1400 	tx_buffer_first = &adapter->tx_buffer_area[adapter->next_avail_tx_desc];
1401 
1402 	/*
1403 	 * Map the packet for DMA.
1404 	 */
1405 	map = tx_buffer_first->map;
1406 	error = bus_dmamap_load_mbuf(adapter->txtag, map, m_head, em_tx_cb,
1407 				     &q, BUS_DMA_NOWAIT);
1408 	if (error != 0) {
1409 		adapter->no_tx_dma_setup++;
1410 		return (error);
1411 	}
1412 	KASSERT(q.nsegs != 0, ("em_encap: empty packet"));
1413 
1414 	if (q.nsegs > (adapter->num_tx_desc_avail - 2)) {
1415 		adapter->no_tx_desc_avail2++;
1416 		error = ENOBUFS;
1417 		goto fail;
1418 	}
1419 
1420 	if (ifp->if_hwassist > 0) {
1421 		em_transmit_checksum_setup(adapter,  m_head,
1422 					   &txd_upper, &txd_lower);
1423 	}
1424 
1425 	/* Find out if we are in vlan mode */
1426 	if ((m_head->m_flags & (M_PROTO1|M_PKTHDR)) == (M_PROTO1|M_PKTHDR) &&
1427 	    m_head->m_pkthdr.rcvif != NULL &&
1428 	    m_head->m_pkthdr.rcvif->if_type == IFT_L2VLAN)
1429 		ifv = m_head->m_pkthdr.rcvif->if_softc;
1430 
1431 	i = adapter->next_avail_tx_desc;
1432 	if (adapter->pcix_82544)
1433 		txd_saved = i;
1434 
1435 	/* Set up our transmit descriptors */
1436 	for (j = 0; j < q.nsegs; j++) {
1437 		/* If adapter is 82544 and on PCIX bus */
1438 		if(adapter->pcix_82544) {
1439 			DESC_ARRAY desc_array;
1440 			uint32_t array_elements, counter;
1441 
1442 			/*
1443 			 * Check the Address and Length combination and
1444 			 * split the data accordingly
1445 			 */
1446 			array_elements = em_fill_descriptors(q.segs[j].ds_addr,
1447 						q.segs[j].ds_len, &desc_array);
1448 			for (counter = 0; counter < array_elements; counter++) {
1449 				if (txd_used == adapter->num_tx_desc_avail) {
1450 					adapter->next_avail_tx_desc = txd_saved;
1451 					adapter->no_tx_desc_avail2++;
1452 					error = ENOBUFS;
1453 					goto fail;
1454 				}
1455 				tx_buffer = &adapter->tx_buffer_area[i];
1456 				current_tx_desc = &adapter->tx_desc_base[i];
1457 				current_tx_desc->buffer_addr = htole64(
1458 					desc_array.descriptor[counter].address);
1459 				current_tx_desc->lower.data = htole32(
1460 					adapter->txd_cmd | txd_lower |
1461 					(uint16_t)desc_array.descriptor[counter].length);
1462 				current_tx_desc->upper.data = htole32(txd_upper);
1463 
1464 				last = i;
1465 				if (++i == adapter->num_tx_desc)
1466 					i = 0;
1467 
1468 				tx_buffer->m_head = NULL;
1469 				tx_buffer->next_eop = -1;
1470 				txd_used++;
1471 			}
1472 		} else {
1473 			tx_buffer = &adapter->tx_buffer_area[i];
1474 			current_tx_desc = &adapter->tx_desc_base[i];
1475 
1476 			current_tx_desc->buffer_addr = htole64(q.segs[j].ds_addr);
1477 			current_tx_desc->lower.data = htole32(
1478 				adapter->txd_cmd | txd_lower | q.segs[j].ds_len);
1479 			current_tx_desc->upper.data = htole32(txd_upper);
1480 
1481 			last = i;
1482 			if (++i == adapter->num_tx_desc)
1483 				i = 0;
1484 
1485 			tx_buffer->m_head = NULL;
1486 			tx_buffer->next_eop = -1;
1487 		}
1488 	}
1489 
1490 	adapter->next_avail_tx_desc = i;
1491 	if (adapter->pcix_82544)
1492 		adapter->num_tx_desc_avail -= txd_used;
1493 	else
1494 		adapter->num_tx_desc_avail -= q.nsegs;
1495 
1496 	if (ifv != NULL) {
1497 		/* Set the vlan id */
1498 		current_tx_desc->upper.fields.special = htole16(ifv->ifv_tag);
1499 
1500 		/* Tell hardware to add tag */
1501 		current_tx_desc->lower.data |= htole32(E1000_TXD_CMD_VLE);
1502 	}
1503 
1504 	tx_buffer->m_head = m_head;
1505 	tx_buffer_first->map = tx_buffer->map;
1506 	tx_buffer->map = map;
1507 	bus_dmamap_sync(adapter->txtag, map, BUS_DMASYNC_PREWRITE);
1508 
1509 	/*
1510 	 * Last Descriptor of Packet needs End Of Packet (EOP)
1511 	 * and Report Status (RS)
1512 	 */
1513 	current_tx_desc->lower.data |=
1514 		htole32(E1000_TXD_CMD_EOP | E1000_TXD_CMD_RS);
1515 
1516 	/*
1517 	 * Keep track in the first buffer which descriptor will be
1518 	 * written back.
1519 	 */
1520 	tx_buffer_first->next_eop = last;
1521 
1522 	bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
1523 			BUS_DMASYNC_PREWRITE);
1524 
1525 	/*
1526 	 * Advance the Transmit Descriptor Tail (Tdt), this tells the E1000
1527 	 * that this frame is available to transmit.
1528 	 */
1529 	if (adapter->hw.mac_type == em_82547 &&
1530 	    adapter->link_duplex == HALF_DUPLEX) {
1531 		em_82547_move_tail_serialized(adapter);
1532 	} else {
1533 		E1000_WRITE_REG(&adapter->hw, TDT, i);
1534 		if (adapter->hw.mac_type == em_82547) {
1535 			em_82547_update_fifo_head(adapter,
1536 						  m_head->m_pkthdr.len);
1537 		}
1538 	}
1539 
1540 	return (0);
1541 fail:
1542 	bus_dmamap_unload(adapter->txtag, map);
1543 	return error;
1544 }
1545 
1546 /*********************************************************************
1547  *
1548  * 82547 workaround to avoid controller hang in half-duplex environment.
1549  * The workaround is to avoid queuing a large packet that would span
1550  * the internal Tx FIFO ring boundary. We need to reset the FIFO pointers
1551  * in this case. We do that only when FIFO is quiescent.
1552  *
1553  **********************************************************************/
1554 static void
1555 em_82547_move_tail(void *arg)
1556 {
1557 	struct adapter *adapter = arg;
1558 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1559 
1560 	lwkt_serialize_enter(ifp->if_serializer);
1561 	em_82547_move_tail_serialized(adapter);
1562 	lwkt_serialize_exit(ifp->if_serializer);
1563 }
1564 
1565 static void
1566 em_82547_move_tail_serialized(struct adapter *adapter)
1567 {
1568 	uint16_t hw_tdt;
1569 	uint16_t sw_tdt;
1570 	struct em_tx_desc *tx_desc;
1571 	uint16_t length = 0;
1572 	boolean_t eop = 0;
1573 
1574 	hw_tdt = E1000_READ_REG(&adapter->hw, TDT);
1575 	sw_tdt = adapter->next_avail_tx_desc;
1576 
1577 	while (hw_tdt != sw_tdt) {
1578 		tx_desc = &adapter->tx_desc_base[hw_tdt];
1579 		length += tx_desc->lower.flags.length;
1580 		eop = tx_desc->lower.data & E1000_TXD_CMD_EOP;
1581 		if (++hw_tdt == adapter->num_tx_desc)
1582 			hw_tdt = 0;
1583 
1584 		if (eop) {
1585 			if (em_82547_fifo_workaround(adapter, length)) {
1586 				adapter->tx_fifo_wrk_cnt++;
1587 				callout_reset(&adapter->tx_fifo_timer, 1,
1588 					em_82547_move_tail, adapter);
1589 				break;
1590 			}
1591 			E1000_WRITE_REG(&adapter->hw, TDT, hw_tdt);
1592 			em_82547_update_fifo_head(adapter, length);
1593 			length = 0;
1594 		}
1595 	}
1596 }
1597 
1598 static int
1599 em_82547_fifo_workaround(struct adapter *adapter, int len)
1600 {
1601 	int fifo_space, fifo_pkt_len;
1602 
1603 	fifo_pkt_len = roundup2(len + EM_FIFO_HDR, EM_FIFO_HDR);
1604 
1605 	if (adapter->link_duplex == HALF_DUPLEX) {
1606 		fifo_space = adapter->tx_fifo_size - adapter->tx_fifo_head;
1607 
1608 		if (fifo_pkt_len >= (EM_82547_PKT_THRESH + fifo_space)) {
1609 			if (em_82547_tx_fifo_reset(adapter))
1610 				return (0);
1611 			else
1612 				return (1);
1613 		}
1614 	}
1615 
1616 	return (0);
1617 }
1618 
1619 static void
1620 em_82547_update_fifo_head(struct adapter *adapter, int len)
1621 {
1622 	int fifo_pkt_len = roundup2(len + EM_FIFO_HDR, EM_FIFO_HDR);
1623 
1624 	/* tx_fifo_head is always 16 byte aligned */
1625 	adapter->tx_fifo_head += fifo_pkt_len;
1626 	if (adapter->tx_fifo_head >= adapter->tx_fifo_size)
1627 		adapter->tx_fifo_head -= adapter->tx_fifo_size;
1628 }
1629 
1630 static int
1631 em_82547_tx_fifo_reset(struct adapter *adapter)
1632 {
1633 	uint32_t tctl;
1634 
1635 	if (E1000_READ_REG(&adapter->hw, TDT) == E1000_READ_REG(&adapter->hw, TDH) &&
1636 	    E1000_READ_REG(&adapter->hw, TDFT) == E1000_READ_REG(&adapter->hw, TDFH) &&
1637 	    E1000_READ_REG(&adapter->hw, TDFTS) == E1000_READ_REG(&adapter->hw, TDFHS) &&
1638 	    E1000_READ_REG(&adapter->hw, TDFPC) == 0) {
1639 		/* Disable TX unit */
1640 		tctl = E1000_READ_REG(&adapter->hw, TCTL);
1641 		E1000_WRITE_REG(&adapter->hw, TCTL, tctl & ~E1000_TCTL_EN);
1642 
1643 		/* Reset FIFO pointers */
1644 		E1000_WRITE_REG(&adapter->hw, TDFT,  adapter->tx_head_addr);
1645 		E1000_WRITE_REG(&adapter->hw, TDFH,  adapter->tx_head_addr);
1646 		E1000_WRITE_REG(&adapter->hw, TDFTS, adapter->tx_head_addr);
1647 		E1000_WRITE_REG(&adapter->hw, TDFHS, adapter->tx_head_addr);
1648 
1649 		/* Re-enable TX unit */
1650 		E1000_WRITE_REG(&adapter->hw, TCTL, tctl);
1651 		E1000_WRITE_FLUSH(&adapter->hw);
1652 
1653 		adapter->tx_fifo_head = 0;
1654 		adapter->tx_fifo_reset_cnt++;
1655 
1656 		return (TRUE);
1657 	} else {
1658 		return (FALSE);
1659 	}
1660 }
1661 
1662 static void
1663 em_set_promisc(struct adapter *adapter)
1664 {
1665 	uint32_t reg_rctl;
1666 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1667 
1668 	reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1669 
1670 	adapter->em_insert_vlan_header = 0;
1671 	if (ifp->if_flags & IFF_PROMISC) {
1672 		reg_rctl |= (E1000_RCTL_UPE | E1000_RCTL_MPE);
1673 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1674 
1675 		/*
1676 		 * Disable VLAN stripping in promiscous mode.
1677 		 * This enables bridging of vlan tagged frames to occur
1678 		 * and also allows vlan tags to be seen in tcpdump.
1679 		 */
1680 		if (ifp->if_capenable & IFCAP_VLAN_HWTAGGING)
1681 			em_disable_vlans(adapter);
1682 		adapter->em_insert_vlan_header = 1;
1683 	} else if (ifp->if_flags & IFF_ALLMULTI) {
1684 		reg_rctl |= E1000_RCTL_MPE;
1685 		reg_rctl &= ~E1000_RCTL_UPE;
1686 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1687 	}
1688 }
1689 
1690 static void
1691 em_disable_promisc(struct adapter *adapter)
1692 {
1693 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1694 
1695 	uint32_t reg_rctl;
1696 
1697 	reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1698 
1699 	reg_rctl &= (~E1000_RCTL_UPE);
1700 	reg_rctl &= (~E1000_RCTL_MPE);
1701 	E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1702 
1703 	if (ifp->if_capenable & IFCAP_VLAN_HWTAGGING)
1704 		em_enable_vlans(adapter);
1705 	adapter->em_insert_vlan_header = 0;
1706 }
1707 
1708 /*********************************************************************
1709  *  Multicast Update
1710  *
1711  *  This routine is called whenever multicast address list is updated.
1712  *
1713  **********************************************************************/
1714 
1715 static void
1716 em_set_multi(struct adapter *adapter)
1717 {
1718 	uint32_t reg_rctl = 0;
1719 	uint8_t mta[MAX_NUM_MULTICAST_ADDRESSES * ETH_LENGTH_OF_ADDRESS];
1720 	struct ifmultiaddr *ifma;
1721 	int mcnt = 0;
1722 	struct ifnet *ifp = &adapter->interface_data.ac_if;
1723 
1724 	IOCTL_DEBUGOUT("em_set_multi: begin");
1725 
1726 	if (adapter->hw.mac_type == em_82542_rev2_0) {
1727 		reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1728 		if (adapter->hw.pci_cmd_word & CMD_MEM_WRT_INVALIDATE)
1729 			em_pci_clear_mwi(&adapter->hw);
1730 		reg_rctl |= E1000_RCTL_RST;
1731 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1732 		msec_delay(5);
1733 	}
1734 
1735 	LIST_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
1736 		if (ifma->ifma_addr->sa_family != AF_LINK)
1737 			continue;
1738 
1739 		if (mcnt == MAX_NUM_MULTICAST_ADDRESSES)
1740 			break;
1741 
1742 		bcopy(LLADDR((struct sockaddr_dl *)ifma->ifma_addr),
1743 		      &mta[mcnt*ETH_LENGTH_OF_ADDRESS], ETH_LENGTH_OF_ADDRESS);
1744 		mcnt++;
1745 	}
1746 
1747 	if (mcnt >= MAX_NUM_MULTICAST_ADDRESSES) {
1748 		reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1749 		reg_rctl |= E1000_RCTL_MPE;
1750 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1751 	} else {
1752 		em_mc_addr_list_update(&adapter->hw, mta, mcnt, 0, 1);
1753 	}
1754 
1755 	if (adapter->hw.mac_type == em_82542_rev2_0) {
1756 		reg_rctl = E1000_READ_REG(&adapter->hw, RCTL);
1757 		reg_rctl &= ~E1000_RCTL_RST;
1758 		E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
1759 		msec_delay(5);
1760 		if (adapter->hw.pci_cmd_word & CMD_MEM_WRT_INVALIDATE)
1761                         em_pci_set_mwi(&adapter->hw);
1762 	}
1763 }
1764 
1765 /*********************************************************************
1766  *  Timer routine
1767  *
1768  *  This routine checks for link status and updates statistics.
1769  *
1770  **********************************************************************/
1771 
1772 static void
1773 em_local_timer(void *arg)
1774 {
1775 	struct ifnet *ifp;
1776 	struct adapter *adapter = arg;
1777 	ifp = &adapter->interface_data.ac_if;
1778 
1779 	lwkt_serialize_enter(ifp->if_serializer);
1780 
1781 	em_check_for_link(&adapter->hw);
1782 	em_update_link_status(adapter);
1783 	em_update_stats_counters(adapter);
1784 	if (em_display_debug_stats && ifp->if_flags & IFF_RUNNING)
1785 		em_print_hw_stats(adapter);
1786 	em_smartspeed(adapter);
1787 
1788 	callout_reset(&adapter->timer, hz, em_local_timer, adapter);
1789 
1790 	lwkt_serialize_exit(ifp->if_serializer);
1791 }
1792 
1793 static void
1794 em_update_link_status(struct adapter *adapter)
1795 {
1796 	struct ifnet *ifp;
1797 	ifp = &adapter->interface_data.ac_if;
1798 
1799 	if (E1000_READ_REG(&adapter->hw, STATUS) & E1000_STATUS_LU) {
1800 		if (adapter->link_active == 0) {
1801 			em_get_speed_and_duplex(&adapter->hw,
1802 						&adapter->link_speed,
1803 						&adapter->link_duplex);
1804 			/* Check if we may set SPEED_MODE bit on PCI-E */
1805 			if (adapter->link_speed == SPEED_1000 &&
1806 			    (adapter->hw.mac_type == em_82571 ||
1807 			     adapter->hw.mac_type == em_82572)) {
1808 				int tarc0;
1809 
1810 				tarc0 = E1000_READ_REG(&adapter->hw, TARC0);
1811 				tarc0 |= SPEED_MODE_BIT;
1812 				E1000_WRITE_REG(&adapter->hw, TARC0, tarc0);
1813 			}
1814 			if (bootverbose) {
1815 				if_printf(&adapter->interface_data.ac_if,
1816 					  "Link is up %d Mbps %s\n",
1817 					  adapter->link_speed,
1818 					  adapter->link_duplex == FULL_DUPLEX ?
1819 						"Full Duplex" : "Half Duplex");
1820 			}
1821 			adapter->link_active = 1;
1822 			adapter->smartspeed = 0;
1823 			ifp->if_baudrate = adapter->link_speed * 1000000;
1824 			ifp->if_link_state = LINK_STATE_UP;
1825 			if_link_state_change(ifp);
1826 		}
1827 	} else {
1828 		if (adapter->link_active == 1) {
1829 			ifp->if_baudrate = 0;
1830 			adapter->link_speed = 0;
1831 			adapter->link_duplex = 0;
1832 			if (bootverbose) {
1833 				if_printf(&adapter->interface_data.ac_if,
1834 					  "Link is Down\n");
1835 			}
1836 			adapter->link_active = 0;
1837 			ifp->if_link_state = LINK_STATE_DOWN;
1838 			if_link_state_change(ifp);
1839 		}
1840 	}
1841 }
1842 
1843 /*********************************************************************
1844  *
1845  *  This routine disables all traffic on the adapter by issuing a
1846  *  global reset on the MAC and deallocates TX/RX buffers.
1847  *
1848  **********************************************************************/
1849 
1850 static void
1851 em_stop(void *arg)
1852 {
1853 	struct ifnet   *ifp;
1854 	struct adapter * adapter = arg;
1855 	ifp = &adapter->interface_data.ac_if;
1856 
1857 	ASSERT_SERIALIZED(ifp->if_serializer);
1858 
1859 	INIT_DEBUGOUT("em_stop: begin");
1860 	em_disable_intr(adapter);
1861 	em_reset_hw(&adapter->hw);
1862 	callout_stop(&adapter->timer);
1863 	callout_stop(&adapter->tx_fifo_timer);
1864 	em_free_transmit_structures(adapter);
1865 	em_free_receive_structures(adapter);
1866 
1867 	/* Tell the stack that the interface is no longer active */
1868 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
1869 	ifp->if_timer = 0;
1870 }
1871 
1872 /*********************************************************************
1873  *
1874  *  Determine hardware revision.
1875  *
1876  **********************************************************************/
1877 static void
1878 em_identify_hardware(struct adapter *adapter)
1879 {
1880 	device_t dev = adapter->dev;
1881 
1882 	/* Make sure our PCI config space has the necessary stuff set */
1883 	adapter->hw.pci_cmd_word = pci_read_config(dev, PCIR_COMMAND, 2);
1884 	if (!((adapter->hw.pci_cmd_word & PCIM_CMD_BUSMASTEREN) &&
1885 	      (adapter->hw.pci_cmd_word & PCIM_CMD_MEMEN))) {
1886 		device_printf(dev, "Memory Access and/or Bus Master bits "
1887 			      "were not set!\n");
1888 		adapter->hw.pci_cmd_word |= PCIM_CMD_BUSMASTEREN |
1889 					    PCIM_CMD_MEMEN;
1890 		pci_write_config(dev, PCIR_COMMAND,
1891 				 adapter->hw.pci_cmd_word, 2);
1892 	}
1893 
1894 	/* Save off the information about this board */
1895 	adapter->hw.vendor_id = pci_get_vendor(dev);
1896 	adapter->hw.device_id = pci_get_device(dev);
1897 	adapter->hw.revision_id = pci_get_revid(dev);
1898 	adapter->hw.subsystem_vendor_id = pci_get_subvendor(dev);
1899 	adapter->hw.subsystem_id = pci_get_subdevice(dev);
1900 
1901 	/* Identify the MAC */
1902 	if (em_set_mac_type(&adapter->hw))
1903 		device_printf(dev, "Unknown MAC Type\n");
1904 
1905 	if (adapter->hw.mac_type == em_82541 ||
1906 	    adapter->hw.mac_type == em_82541_rev_2 ||
1907 	    adapter->hw.mac_type == em_82547 ||
1908 	    adapter->hw.mac_type == em_82547_rev_2)
1909 		adapter->hw.phy_init_script = TRUE;
1910 }
1911 
1912 static int
1913 em_allocate_pci_resources(device_t dev)
1914 {
1915 	struct adapter *adapter = device_get_softc(dev);
1916 	int rid;
1917 
1918 	rid = PCIR_BAR(0);
1919 	adapter->res_memory = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
1920 						     &rid, RF_ACTIVE);
1921 	if (adapter->res_memory == NULL) {
1922 		device_printf(dev, "Unable to allocate bus resource: memory\n");
1923 		return ENXIO;
1924 	}
1925 	adapter->osdep.mem_bus_space_tag =
1926 		rman_get_bustag(adapter->res_memory);
1927 	adapter->osdep.mem_bus_space_handle =
1928 	    rman_get_bushandle(adapter->res_memory);
1929 	adapter->hw.hw_addr = (uint8_t *)&adapter->osdep.mem_bus_space_handle;
1930 
1931 	if (adapter->hw.mac_type > em_82543) {
1932 		/* Figure our where our IO BAR is ? */
1933 		for (rid = PCIR_BAR(0); rid < PCIR_CIS;) {
1934 			uint32_t val;
1935 
1936 			val = pci_read_config(dev, rid, 4);
1937 			if (EM_BAR_TYPE(val) == EM_BAR_TYPE_IO) {
1938 				adapter->io_rid = rid;
1939 				break;
1940 			}
1941 			rid += 4;
1942 			/* check for 64bit BAR */
1943 			if (EM_BAR_MEM_TYPE(val) == EM_BAR_MEM_TYPE_64BIT)
1944 				rid += 4;
1945 		}
1946 		if (rid >= PCIR_CIS) {
1947 			device_printf(dev, "Unable to locate IO BAR\n");
1948 			return (ENXIO);
1949  		}
1950 
1951 		adapter->res_ioport = bus_alloc_resource_any(dev,
1952 		    SYS_RES_IOPORT, &adapter->io_rid, RF_ACTIVE);
1953 		if (!(adapter->res_ioport)) {
1954 			device_printf(dev, "Unable to allocate bus resource: "
1955 				      "ioport\n");
1956 			return ENXIO;
1957 		}
1958 		adapter->hw.io_base = 0;
1959 		adapter->osdep.io_bus_space_tag =
1960 			rman_get_bustag(adapter->res_ioport);
1961 		adapter->osdep.io_bus_space_handle =
1962 			rman_get_bushandle(adapter->res_ioport);
1963 	}
1964 
1965 	/* For ICH8 we need to find the flash memory. */
1966 	if (adapter->hw.mac_type == em_ich8lan) {
1967 		rid = EM_FLASH;
1968 		adapter->flash_mem = bus_alloc_resource_any(dev,
1969 		    SYS_RES_MEMORY, &rid, RF_ACTIVE);
1970 		if (adapter->flash_mem == NULL) {
1971 			device_printf(dev, "Unable to allocate bus resource: "
1972 				      "flash memory\n");
1973 			return ENXIO;
1974 		}
1975 		adapter->osdep.flash_bus_space_tag =
1976 		    rman_get_bustag(adapter->flash_mem);
1977 		adapter->osdep.flash_bus_space_handle =
1978 		    rman_get_bushandle(adapter->flash_mem);
1979 	}
1980 
1981 	rid = 0x0;
1982 	adapter->res_interrupt = bus_alloc_resource_any(dev, SYS_RES_IRQ,
1983 	    &rid, RF_SHAREABLE | RF_ACTIVE);
1984 	if (adapter->res_interrupt == NULL) {
1985 		device_printf(dev, "Unable to allocate bus resource: "
1986 			      "interrupt\n");
1987 		return ENXIO;
1988 	}
1989 
1990 	adapter->hw.back = &adapter->osdep;
1991 
1992 	return 0;
1993 }
1994 
1995 static void
1996 em_free_pci_resources(device_t dev)
1997 {
1998 	struct adapter *adapter = device_get_softc(dev);
1999 
2000 	if (adapter->res_interrupt != NULL) {
2001 		bus_release_resource(dev, SYS_RES_IRQ, 0,
2002 				     adapter->res_interrupt);
2003 	}
2004 	if (adapter->res_memory != NULL) {
2005 		bus_release_resource(dev, SYS_RES_MEMORY, PCIR_BAR(0),
2006 				     adapter->res_memory);
2007 	}
2008 
2009 	if (adapter->res_ioport != NULL) {
2010 		bus_release_resource(dev, SYS_RES_IOPORT, adapter->io_rid,
2011 				     adapter->res_ioport);
2012 	}
2013 
2014 	if (adapter->flash_mem != NULL) {
2015 		bus_release_resource(dev, SYS_RES_MEMORY, EM_FLASH,
2016 				     adapter->flash_mem);
2017 	}
2018 }
2019 
2020 /*********************************************************************
2021  *
2022  *  Initialize the hardware to a configuration as specified by the
2023  *  adapter structure. The controller is reset, the EEPROM is
2024  *  verified, the MAC address is set, then the shared initialization
2025  *  routines are called.
2026  *
2027  **********************************************************************/
2028 static int
2029 em_hardware_init(struct adapter *adapter)
2030 {
2031 	uint16_t	rx_buffer_size;
2032 
2033 	INIT_DEBUGOUT("em_hardware_init: begin");
2034 	/* Issue a global reset */
2035 	em_reset_hw(&adapter->hw);
2036 
2037 	/* When hardware is reset, fifo_head is also reset */
2038 	adapter->tx_fifo_head = 0;
2039 
2040 	/* Make sure we have a good EEPROM before we read from it */
2041 	if (em_validate_eeprom_checksum(&adapter->hw) < 0) {
2042 		if (em_validate_eeprom_checksum(&adapter->hw) < 0) {
2043 			device_printf(adapter->dev,
2044 				      "The EEPROM Checksum Is Not Valid\n");
2045 			return (EIO);
2046 		}
2047 	}
2048 
2049 	if (em_read_part_num(&adapter->hw, &(adapter->part_num)) < 0) {
2050 		device_printf(adapter->dev,
2051 			      "EEPROM read error while reading part number\n");
2052 		return (EIO);
2053 	}
2054 
2055 	/* Set up smart power down as default off on newer adapters. */
2056 	if (!em_smart_pwr_down &&
2057 	    (adapter->hw.mac_type == em_82571 ||
2058 	     adapter->hw.mac_type == em_82572)) {
2059 		uint16_t phy_tmp = 0;
2060 
2061 		/* Speed up time to link by disabling smart power down. */
2062 		em_read_phy_reg(&adapter->hw, IGP02E1000_PHY_POWER_MGMT,
2063 				&phy_tmp);
2064 		phy_tmp &= ~IGP02E1000_PM_SPD;
2065 		em_write_phy_reg(&adapter->hw, IGP02E1000_PHY_POWER_MGMT,
2066 				 phy_tmp);
2067 	}
2068 
2069 	/*
2070 	 * These parameters control the automatic generation (Tx) and
2071 	 * response (Rx) to Ethernet PAUSE frames.
2072 	 * - High water mark should allow for at least two frames to be
2073 	 *   received after sending an XOFF.
2074 	 * - Low water mark works best when it is very near the high water mark.
2075 	 *   This allows the receiver to restart by sending XON when it has
2076 	 *   drained a bit.  Here we use an arbitary value of 1500 which will
2077 	 *   restart after one full frame is pulled from the buffer.  There
2078 	 *   could be several smaller frames in the buffer and if so they will
2079 	 *   not trigger the XON until their total number reduces the buffer
2080 	 *   by 1500.
2081 	 * - The pause time is fairly large at 1000 x 512ns = 512 usec.
2082 	 */
2083 	rx_buffer_size = ((E1000_READ_REG(&adapter->hw, PBA) & 0xffff) << 10);
2084 
2085 	adapter->hw.fc_high_water =
2086 	    rx_buffer_size - roundup2(adapter->hw.max_frame_size, 1024);
2087 	adapter->hw.fc_low_water = adapter->hw.fc_high_water - 1500;
2088 	if (adapter->hw.mac_type == em_80003es2lan)
2089 		adapter->hw.fc_pause_time = 0xFFFF;
2090 	else
2091 		adapter->hw.fc_pause_time = 0x1000;
2092 	adapter->hw.fc_send_xon = TRUE;
2093 	adapter->hw.fc = E1000_FC_FULL;
2094 
2095 	if (em_init_hw(&adapter->hw) < 0) {
2096 		device_printf(adapter->dev, "Hardware Initialization Failed");
2097 		return (EIO);
2098 	}
2099 
2100 	em_check_for_link(&adapter->hw);
2101 
2102 	return (0);
2103 }
2104 
2105 /*********************************************************************
2106  *
2107  *  Setup networking device structure and register an interface.
2108  *
2109  **********************************************************************/
2110 static void
2111 em_setup_interface(device_t dev, struct adapter *adapter)
2112 {
2113 	struct ifnet *ifp;
2114 	u_char fiber_type = IFM_1000_SX;	/* default type */
2115 	INIT_DEBUGOUT("em_setup_interface: begin");
2116 
2117 	ifp = &adapter->interface_data.ac_if;
2118 	if_initname(ifp, device_get_name(dev), device_get_unit(dev));
2119 	ifp->if_mtu = ETHERMTU;
2120 	ifp->if_baudrate = 1000000000;
2121 	ifp->if_init =  em_init;
2122 	ifp->if_softc = adapter;
2123 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
2124 	ifp->if_ioctl = em_ioctl;
2125 	ifp->if_start = em_start;
2126 #ifdef DEVICE_POLLING
2127 	ifp->if_poll = em_poll;
2128 #endif
2129 	ifp->if_watchdog = em_watchdog;
2130 	ifq_set_maxlen(&ifp->if_snd, adapter->num_tx_desc - 1);
2131 	ifq_set_ready(&ifp->if_snd);
2132 
2133 	if (adapter->hw.mac_type >= em_82543)
2134 		ifp->if_capabilities |= IFCAP_HWCSUM;
2135 
2136 	ifp->if_capenable = ifp->if_capabilities;
2137 
2138 	ether_ifattach(ifp, adapter->hw.mac_addr, NULL);
2139 
2140 	/*
2141 	 * Tell the upper layer(s) we support long frames.
2142 	 */
2143 	ifp->if_data.ifi_hdrlen = sizeof(struct ether_vlan_header);
2144 	ifp->if_capabilities |= IFCAP_VLAN_HWTAGGING | IFCAP_VLAN_MTU;
2145 #if 0
2146 	ifp->if_capenable |= IFCAP_VLAN_MTU;
2147 #endif
2148 
2149 	/*
2150 	 * Specify the media types supported by this adapter and register
2151 	 * callbacks to update media and link information
2152 	 */
2153 	ifmedia_init(&adapter->media, IFM_IMASK, em_media_change,
2154 		     em_media_status);
2155 	if (adapter->hw.media_type == em_media_type_fiber ||
2156 	    adapter->hw.media_type == em_media_type_internal_serdes) {
2157 		if (adapter->hw.mac_type == em_82545)
2158 			fiber_type = IFM_1000_LX;
2159 		ifmedia_add(&adapter->media, IFM_ETHER | fiber_type | IFM_FDX,
2160 			    0, NULL);
2161 		ifmedia_add(&adapter->media, IFM_ETHER | fiber_type, 0, NULL);
2162 	} else {
2163 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_10_T, 0, NULL);
2164 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_10_T | IFM_FDX,
2165 			    0, NULL);
2166 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_100_TX,
2167 			    0, NULL);
2168 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_100_TX | IFM_FDX,
2169 			    0, NULL);
2170 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_1000_T | IFM_FDX,
2171 			    0, NULL);
2172 		ifmedia_add(&adapter->media, IFM_ETHER | IFM_1000_T, 0, NULL);
2173 	}
2174 	ifmedia_add(&adapter->media, IFM_ETHER | IFM_AUTO, 0, NULL);
2175 	ifmedia_set(&adapter->media, IFM_ETHER | IFM_AUTO);
2176 }
2177 
2178 /*********************************************************************
2179  *
2180  *  Workaround for SmartSpeed on 82541 and 82547 controllers
2181  *
2182  **********************************************************************/
2183 static void
2184 em_smartspeed(struct adapter *adapter)
2185 {
2186 	uint16_t phy_tmp;
2187 
2188 	if (adapter->link_active || (adapter->hw.phy_type != em_phy_igp) ||
2189 	    !adapter->hw.autoneg ||
2190 	    !(adapter->hw.autoneg_advertised & ADVERTISE_1000_FULL))
2191 		return;
2192 
2193 	if (adapter->smartspeed == 0) {
2194 		/*
2195 		 * If Master/Slave config fault is asserted twice,
2196 		 * we assume back-to-back.
2197 		 */
2198 		em_read_phy_reg(&adapter->hw, PHY_1000T_STATUS, &phy_tmp);
2199 		if (!(phy_tmp & SR_1000T_MS_CONFIG_FAULT))
2200 			return;
2201 		em_read_phy_reg(&adapter->hw, PHY_1000T_STATUS, &phy_tmp);
2202 		if (phy_tmp & SR_1000T_MS_CONFIG_FAULT) {
2203 			em_read_phy_reg(&adapter->hw, PHY_1000T_CTRL, &phy_tmp);
2204 			if (phy_tmp & CR_1000T_MS_ENABLE) {
2205 				phy_tmp &= ~CR_1000T_MS_ENABLE;
2206 				em_write_phy_reg(&adapter->hw,
2207 						 PHY_1000T_CTRL, phy_tmp);
2208 				adapter->smartspeed++;
2209 				if (adapter->hw.autoneg &&
2210 				    !em_phy_setup_autoneg(&adapter->hw) &&
2211 				    !em_read_phy_reg(&adapter->hw, PHY_CTRL,
2212 						     &phy_tmp)) {
2213 					phy_tmp |= (MII_CR_AUTO_NEG_EN |
2214 						    MII_CR_RESTART_AUTO_NEG);
2215 					em_write_phy_reg(&adapter->hw,
2216 							 PHY_CTRL, phy_tmp);
2217 				}
2218 			}
2219 		}
2220 		return;
2221 	} else if (adapter->smartspeed == EM_SMARTSPEED_DOWNSHIFT) {
2222 		/* If still no link, perhaps using 2/3 pair cable */
2223 		em_read_phy_reg(&adapter->hw, PHY_1000T_CTRL, &phy_tmp);
2224 		phy_tmp |= CR_1000T_MS_ENABLE;
2225 		em_write_phy_reg(&adapter->hw, PHY_1000T_CTRL, phy_tmp);
2226 		if (adapter->hw.autoneg &&
2227 		    !em_phy_setup_autoneg(&adapter->hw) &&
2228 		    !em_read_phy_reg(&adapter->hw, PHY_CTRL, &phy_tmp)) {
2229 			phy_tmp |= (MII_CR_AUTO_NEG_EN |
2230 				    MII_CR_RESTART_AUTO_NEG);
2231 			em_write_phy_reg(&adapter->hw, PHY_CTRL, phy_tmp);
2232 		}
2233 	}
2234 	/* Restart process after EM_SMARTSPEED_MAX iterations */
2235 	if (adapter->smartspeed++ == EM_SMARTSPEED_MAX)
2236 		adapter->smartspeed = 0;
2237 }
2238 
2239 /*
2240  * Manage DMA'able memory.
2241  */
2242 static void
2243 em_dmamap_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error)
2244 {
2245 	if (error)
2246 		return;
2247 	*(bus_addr_t *)arg = segs->ds_addr;
2248 }
2249 
2250 static int
2251 em_dma_malloc(struct adapter *adapter, bus_size_t size,
2252 	      struct em_dma_alloc *dma)
2253 {
2254 	device_t dev = adapter->dev;
2255 	int error;
2256 
2257 	error = bus_dma_tag_create(NULL,		/* parent */
2258 				   EM_DBA_ALIGN, 0,	/* alignment, bounds */
2259 				   BUS_SPACE_MAXADDR,	/* lowaddr */
2260 				   BUS_SPACE_MAXADDR,	/* highaddr */
2261 				   NULL, NULL,		/* filter, filterarg */
2262 				   size,		/* maxsize */
2263 				   1,			/* nsegments */
2264 				   size,		/* maxsegsize */
2265 				   0,			/* flags */
2266 				   &dma->dma_tag);
2267 	if (error) {
2268 		device_printf(dev, "%s: bus_dma_tag_create failed; error %d\n",
2269 			      __func__, error);
2270 		return error;
2271 	}
2272 
2273 	error = bus_dmamem_alloc(dma->dma_tag, (void**)&dma->dma_vaddr,
2274 				 BUS_DMA_WAITOK, &dma->dma_map);
2275 	if (error) {
2276 		device_printf(dev, "%s: bus_dmammem_alloc failed; "
2277 			      "size %llu, error %d\n",
2278 			      __func__, (uintmax_t)size, error);
2279 		goto fail;
2280 	}
2281 
2282 	error = bus_dmamap_load(dma->dma_tag, dma->dma_map,
2283 				dma->dma_vaddr, size,
2284 				em_dmamap_cb, &dma->dma_paddr,
2285 				BUS_DMA_WAITOK);
2286 	if (error) {
2287 		device_printf(dev, "%s: bus_dmamap_load failed; error %u\n",
2288 			      __func__, error);
2289 		bus_dmamem_free(dma->dma_tag, dma->dma_vaddr, dma->dma_map);
2290 		goto fail;
2291 	}
2292 
2293 	return 0;
2294 fail:
2295 	bus_dma_tag_destroy(dma->dma_tag);
2296 	dma->dma_tag = NULL;
2297 	return error;
2298 }
2299 
2300 static void
2301 em_dma_free(struct adapter *adapter, struct em_dma_alloc *dma)
2302 {
2303 	if (dma->dma_tag != NULL) {
2304 		bus_dmamap_unload(dma->dma_tag, dma->dma_map);
2305 		bus_dmamem_free(dma->dma_tag, dma->dma_vaddr, dma->dma_map);
2306 		bus_dma_tag_destroy(dma->dma_tag);
2307 		dma->dma_tag = NULL;
2308 	}
2309 }
2310 
2311 /*********************************************************************
2312  *
2313  *  Allocate and initialize transmit structures.
2314  *
2315  **********************************************************************/
2316 static int
2317 em_setup_transmit_structures(struct adapter *adapter)
2318 {
2319 	struct em_buffer *tx_buffer;
2320 	bus_size_t size;
2321 	int error, i;
2322 
2323 	/*
2324 	 * Setup DMA descriptor areas.
2325 	 */
2326 	size = roundup2(adapter->hw.max_frame_size, MCLBYTES);
2327 	if (bus_dma_tag_create(NULL,			/* parent */
2328 			       1, 0,			/* alignment, bounds */
2329 			       BUS_SPACE_MAXADDR,	/* lowaddr */
2330 			       BUS_SPACE_MAXADDR,	/* highaddr */
2331 			       NULL, NULL,		/* filter, filterarg */
2332 			       size,			/* maxsize */
2333 			       EM_MAX_SCATTER,		/* nsegments */
2334 			       size,			/* maxsegsize */
2335 			       0,			/* flags */
2336 			       &adapter->txtag)) {
2337 		device_printf(adapter->dev, "Unable to allocate TX DMA tag\n");
2338 		return(ENOMEM);
2339 	}
2340 
2341 	adapter->tx_buffer_area =
2342 		kmalloc(sizeof(struct em_buffer) * adapter->num_tx_desc,
2343 			M_DEVBUF, M_WAITOK | M_ZERO);
2344 
2345 	bzero(adapter->tx_desc_base,
2346 	      sizeof(struct em_tx_desc) * adapter->num_tx_desc);
2347 	tx_buffer = adapter->tx_buffer_area;
2348 	for (i = 0; i < adapter->num_tx_desc; i++) {
2349 		error = bus_dmamap_create(adapter->txtag, 0, &tx_buffer->map);
2350 		if (error) {
2351 			device_printf(adapter->dev,
2352 				      "Unable to create TX DMA map\n");
2353 			goto fail;
2354 		}
2355 		tx_buffer++;
2356 	}
2357 
2358 	adapter->next_avail_tx_desc = 0;
2359 	adapter->next_tx_to_clean = 0;
2360 
2361 	/* Set number of descriptors available */
2362 	adapter->num_tx_desc_avail = adapter->num_tx_desc;
2363 
2364 	/* Set checksum context */
2365 	adapter->active_checksum_context = OFFLOAD_NONE;
2366 
2367 	bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
2368 			BUS_DMASYNC_PREWRITE);
2369 
2370 	return (0);
2371 fail:
2372 	em_free_transmit_structures(adapter);
2373 	return (error);
2374 }
2375 
2376 /*********************************************************************
2377  *
2378  *  Enable transmit unit.
2379  *
2380  **********************************************************************/
2381 static void
2382 em_initialize_transmit_unit(struct adapter *adapter)
2383 {
2384 	uint32_t reg_tctl;
2385 	uint32_t reg_tipg = 0;
2386 	uint64_t bus_addr;
2387 
2388 	INIT_DEBUGOUT("em_initialize_transmit_unit: begin");
2389 
2390 	/* Setup the Base and Length of the Tx Descriptor Ring */
2391 	bus_addr = adapter->txdma.dma_paddr;
2392 	E1000_WRITE_REG(&adapter->hw, TDLEN,
2393 			adapter->num_tx_desc * sizeof(struct em_tx_desc));
2394 	E1000_WRITE_REG(&adapter->hw, TDBAH, (uint32_t)(bus_addr >> 32));
2395 	E1000_WRITE_REG(&adapter->hw, TDBAL, (uint32_t)bus_addr);
2396 
2397 	/* Setup the HW Tx Head and Tail descriptor pointers */
2398 	E1000_WRITE_REG(&adapter->hw, TDT, 0);
2399 	E1000_WRITE_REG(&adapter->hw, TDH, 0);
2400 
2401 	HW_DEBUGOUT2("Base = %x, Length = %x\n",
2402 		     E1000_READ_REG(&adapter->hw, TDBAL),
2403 		     E1000_READ_REG(&adapter->hw, TDLEN));
2404 
2405 	/* Set the default values for the Tx Inter Packet Gap timer */
2406 	switch (adapter->hw.mac_type) {
2407 	case em_82542_rev2_0:
2408 	case em_82542_rev2_1:
2409 		reg_tipg = DEFAULT_82542_TIPG_IPGT;
2410 		reg_tipg |= DEFAULT_82542_TIPG_IPGR1 << E1000_TIPG_IPGR1_SHIFT;
2411 		reg_tipg |= DEFAULT_82542_TIPG_IPGR2 << E1000_TIPG_IPGR2_SHIFT;
2412 		break;
2413 	case em_80003es2lan:
2414 		reg_tipg = DEFAULT_82543_TIPG_IPGR1;
2415 		reg_tipg |=
2416 		    DEFAULT_80003ES2LAN_TIPG_IPGR2 << E1000_TIPG_IPGR2_SHIFT;
2417 		break;
2418 	default:
2419 		if (adapter->hw.media_type == em_media_type_fiber ||
2420 		    adapter->hw.media_type == em_media_type_internal_serdes)
2421 			reg_tipg = DEFAULT_82543_TIPG_IPGT_FIBER;
2422 		else
2423 			reg_tipg = DEFAULT_82543_TIPG_IPGT_COPPER;
2424 		reg_tipg |= DEFAULT_82543_TIPG_IPGR1 << E1000_TIPG_IPGR1_SHIFT;
2425 		reg_tipg |= DEFAULT_82543_TIPG_IPGR2 << E1000_TIPG_IPGR2_SHIFT;
2426 	}
2427 
2428 	E1000_WRITE_REG(&adapter->hw, TIPG, reg_tipg);
2429 	E1000_WRITE_REG(&adapter->hw, TIDV, adapter->tx_int_delay.value);
2430 	if (adapter->hw.mac_type >= em_82540) {
2431 		E1000_WRITE_REG(&adapter->hw, TADV,
2432 				adapter->tx_abs_int_delay.value);
2433 	}
2434 
2435 	/* Program the Transmit Control Register */
2436 	reg_tctl = E1000_TCTL_PSP | E1000_TCTL_EN |
2437 		   (E1000_COLLISION_THRESHOLD << E1000_CT_SHIFT);
2438 	if (adapter->hw.mac_type >= em_82571)
2439 		reg_tctl |= E1000_TCTL_MULR;
2440 	if (adapter->link_duplex == 1)
2441 		reg_tctl |= E1000_FDX_COLLISION_DISTANCE << E1000_COLD_SHIFT;
2442 	else
2443 		reg_tctl |= E1000_HDX_COLLISION_DISTANCE << E1000_COLD_SHIFT;
2444 
2445 	/* This write will effectively turn on the transmit unit. */
2446 	E1000_WRITE_REG(&adapter->hw, TCTL, reg_tctl);
2447 
2448 	/* Setup Transmit Descriptor Base Settings */
2449 	adapter->txd_cmd = E1000_TXD_CMD_IFCS;
2450 
2451 	if (adapter->tx_int_delay.value > 0)
2452 		adapter->txd_cmd |= E1000_TXD_CMD_IDE;
2453 }
2454 
2455 /*********************************************************************
2456  *
2457  *  Free all transmit related data structures.
2458  *
2459  **********************************************************************/
2460 static void
2461 em_free_transmit_structures(struct adapter *adapter)
2462 {
2463 	struct em_buffer *tx_buffer;
2464 	int i;
2465 
2466 	INIT_DEBUGOUT("free_transmit_structures: begin");
2467 
2468 	if (adapter->tx_buffer_area != NULL) {
2469 		tx_buffer = adapter->tx_buffer_area;
2470 		for (i = 0; i < adapter->num_tx_desc; i++, tx_buffer++) {
2471 			if (tx_buffer->m_head != NULL) {
2472 				bus_dmamap_unload(adapter->txtag,
2473 						  tx_buffer->map);
2474 				m_freem(tx_buffer->m_head);
2475 			}
2476 
2477 			if (tx_buffer->map != NULL) {
2478 				bus_dmamap_destroy(adapter->txtag, tx_buffer->map);
2479 				tx_buffer->map = NULL;
2480  			}
2481 			tx_buffer->m_head = NULL;
2482 		}
2483 	}
2484 	if (adapter->tx_buffer_area != NULL) {
2485 		kfree(adapter->tx_buffer_area, M_DEVBUF);
2486 		adapter->tx_buffer_area = NULL;
2487 	}
2488 	if (adapter->txtag != NULL) {
2489 		bus_dma_tag_destroy(adapter->txtag);
2490 		adapter->txtag = NULL;
2491 	}
2492 }
2493 
2494 /*********************************************************************
2495  *
2496  *  The offload context needs to be set when we transfer the first
2497  *  packet of a particular protocol (TCP/UDP). We change the
2498  *  context only if the protocol type changes.
2499  *
2500  **********************************************************************/
2501 static void
2502 em_transmit_checksum_setup(struct adapter *adapter,
2503 			   struct mbuf *mp,
2504 			   uint32_t *txd_upper,
2505 			   uint32_t *txd_lower)
2506 {
2507 	struct em_context_desc *TXD;
2508 	struct em_buffer *tx_buffer;
2509 	int curr_txd;
2510 
2511 	if (mp->m_pkthdr.csum_flags) {
2512 		if (mp->m_pkthdr.csum_flags & CSUM_TCP) {
2513 			*txd_upper = E1000_TXD_POPTS_TXSM << 8;
2514 			*txd_lower = E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D;
2515 			if (adapter->active_checksum_context == OFFLOAD_TCP_IP)
2516 				return;
2517 			else
2518 				adapter->active_checksum_context = OFFLOAD_TCP_IP;
2519 		} else if (mp->m_pkthdr.csum_flags & CSUM_UDP) {
2520 			*txd_upper = E1000_TXD_POPTS_TXSM << 8;
2521 			*txd_lower = E1000_TXD_CMD_DEXT | E1000_TXD_DTYP_D;
2522 			if (adapter->active_checksum_context == OFFLOAD_UDP_IP)
2523 				return;
2524 			else
2525 				adapter->active_checksum_context = OFFLOAD_UDP_IP;
2526 		} else {
2527 			*txd_upper = 0;
2528 			*txd_lower = 0;
2529 			return;
2530 		}
2531 	} else {
2532 		*txd_upper = 0;
2533 		*txd_lower = 0;
2534 		return;
2535 	}
2536 
2537 	/*
2538 	 * If we reach this point, the checksum offload context
2539 	 * needs to be reset.
2540 	 */
2541 	curr_txd = adapter->next_avail_tx_desc;
2542 	tx_buffer = &adapter->tx_buffer_area[curr_txd];
2543 	TXD = (struct em_context_desc *) &adapter->tx_desc_base[curr_txd];
2544 
2545 	TXD->lower_setup.ip_fields.ipcss = ETHER_HDR_LEN;
2546 	TXD->lower_setup.ip_fields.ipcso =
2547 	    ETHER_HDR_LEN + offsetof(struct ip, ip_sum);
2548 	TXD->lower_setup.ip_fields.ipcse =
2549 	    htole16(ETHER_HDR_LEN + sizeof(struct ip) - 1);
2550 
2551 	TXD->upper_setup.tcp_fields.tucss =
2552 	    ETHER_HDR_LEN + sizeof(struct ip);
2553 	TXD->upper_setup.tcp_fields.tucse = htole16(0);
2554 
2555 	if (adapter->active_checksum_context == OFFLOAD_TCP_IP) {
2556 		TXD->upper_setup.tcp_fields.tucso =
2557 			ETHER_HDR_LEN + sizeof(struct ip) +
2558 			offsetof(struct tcphdr, th_sum);
2559 	} else if (adapter->active_checksum_context == OFFLOAD_UDP_IP) {
2560 		TXD->upper_setup.tcp_fields.tucso =
2561 			ETHER_HDR_LEN + sizeof(struct ip) +
2562 			offsetof(struct udphdr, uh_sum);
2563 	}
2564 
2565 	TXD->tcp_seg_setup.data = htole32(0);
2566 	TXD->cmd_and_length = htole32(adapter->txd_cmd | E1000_TXD_CMD_DEXT);
2567 
2568 	tx_buffer->m_head = NULL;
2569 	tx_buffer->next_eop = -1;
2570 
2571 	if (++curr_txd == adapter->num_tx_desc)
2572 		curr_txd = 0;
2573 
2574 	adapter->num_tx_desc_avail--;
2575 	adapter->next_avail_tx_desc = curr_txd;
2576 }
2577 
2578 /**********************************************************************
2579  *
2580  *  Examine each tx_buffer in the used queue. If the hardware is done
2581  *  processing the packet then free associated resources. The
2582  *  tx_buffer is put back on the free queue.
2583  *
2584  **********************************************************************/
2585 
2586 static void
2587 em_txeof(struct adapter *adapter)
2588 {
2589 	int first, last, done, num_avail;
2590 	struct em_buffer *tx_buffer;
2591 	struct em_tx_desc *tx_desc, *eop_desc;
2592 	struct ifnet *ifp = &adapter->interface_data.ac_if;
2593 
2594 	if (adapter->num_tx_desc_avail == adapter->num_tx_desc)
2595 		return;
2596 
2597 	num_avail = adapter->num_tx_desc_avail;
2598 	first = adapter->next_tx_to_clean;
2599 	tx_desc = &adapter->tx_desc_base[first];
2600 	tx_buffer = &adapter->tx_buffer_area[first];
2601 	last = tx_buffer->next_eop;
2602 	KKASSERT(last >= 0 && last < adapter->num_tx_desc);
2603 	eop_desc = &adapter->tx_desc_base[last];
2604 
2605 	/*
2606 	 * Now caculate the terminating index for the cleanup loop below
2607 	 */
2608 	if (++last == adapter->num_tx_desc)
2609 		last = 0;
2610 	done = last;
2611 
2612 	bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
2613 			BUS_DMASYNC_POSTREAD);
2614 
2615 	while (eop_desc->upper.fields.status & E1000_TXD_STAT_DD) {
2616 		while (first != done) {
2617 			tx_desc->upper.data = 0;
2618 			tx_desc->lower.data = 0;
2619 			num_avail++;
2620 
2621 			logif(pkt_txclean);
2622 
2623 			if (tx_buffer->m_head) {
2624 				ifp->if_opackets++;
2625 				bus_dmamap_sync(adapter->txtag, tx_buffer->map,
2626 						BUS_DMASYNC_POSTWRITE);
2627 				bus_dmamap_unload(adapter->txtag,
2628 						  tx_buffer->map);
2629 
2630 				m_freem(tx_buffer->m_head);
2631 				tx_buffer->m_head = NULL;
2632 			}
2633 			tx_buffer->next_eop = -1;
2634 
2635 			if (++first == adapter->num_tx_desc)
2636 				first = 0;
2637 
2638 			tx_buffer = &adapter->tx_buffer_area[first];
2639 			tx_desc = &adapter->tx_desc_base[first];
2640 		}
2641 		/* See if we can continue to the next packet */
2642 		last = tx_buffer->next_eop;
2643 		if (last != -1) {
2644 			KKASSERT(last >= 0 && last < adapter->num_tx_desc);
2645 			eop_desc = &adapter->tx_desc_base[last];
2646 			if (++last == adapter->num_tx_desc)
2647 				last = 0;
2648 			done = last;
2649 		} else {
2650 			break;
2651 		}
2652 	}
2653 
2654 	bus_dmamap_sync(adapter->txdma.dma_tag, adapter->txdma.dma_map,
2655 			BUS_DMASYNC_PREWRITE);
2656 
2657 	adapter->next_tx_to_clean = first;
2658 
2659 	/*
2660 	 * If we have enough room, clear IFF_OACTIVE to tell the stack
2661 	 * that it is OK to send packets.
2662 	 * If there are no pending descriptors, clear the timeout. Otherwise,
2663 	 * if some descriptors have been freed, restart the timeout.
2664 	 */
2665 	if (num_avail > EM_TX_CLEANUP_THRESHOLD) {
2666 		ifp->if_flags &= ~IFF_OACTIVE;
2667 		if (num_avail == adapter->num_tx_desc)
2668 			ifp->if_timer = 0;
2669 		else if (num_avail == adapter->num_tx_desc_avail)
2670 			ifp->if_timer = EM_TX_TIMEOUT;
2671 	}
2672 	adapter->num_tx_desc_avail = num_avail;
2673 }
2674 
2675 /*********************************************************************
2676  *
2677  *  Get a buffer from system mbuf buffer pool.
2678  *
2679  **********************************************************************/
2680 static int
2681 em_get_buf(int i, struct adapter *adapter, struct mbuf *nmp, int how)
2682 {
2683 	struct mbuf *mp = nmp;
2684 	struct em_buffer *rx_buffer;
2685 	struct ifnet *ifp;
2686 	bus_addr_t paddr;
2687 	int error;
2688 
2689 	ifp = &adapter->interface_data.ac_if;
2690 
2691 	if (mp == NULL) {
2692 		mp = m_getcl(how, MT_DATA, M_PKTHDR);
2693 		if (mp == NULL) {
2694 			adapter->mbuf_cluster_failed++;
2695 			return (ENOBUFS);
2696 		}
2697 		mp->m_len = mp->m_pkthdr.len = MCLBYTES;
2698 	} else {
2699 		mp->m_len = mp->m_pkthdr.len = MCLBYTES;
2700 		mp->m_data = mp->m_ext.ext_buf;
2701 		mp->m_next = NULL;
2702 	}
2703 
2704 	if (ifp->if_mtu <= ETHERMTU)
2705 		m_adj(mp, ETHER_ALIGN);
2706 
2707 	rx_buffer = &adapter->rx_buffer_area[i];
2708 
2709 	/*
2710 	 * Using memory from the mbuf cluster pool, invoke the
2711 	 * bus_dma machinery to arrange the memory mapping.
2712 	 */
2713 	error = bus_dmamap_load(adapter->rxtag, rx_buffer->map,
2714 				mtod(mp, void *), mp->m_len,
2715 				em_dmamap_cb, &paddr, 0);
2716 	if (error) {
2717 		m_free(mp);
2718 		return (error);
2719 	}
2720 	rx_buffer->m_head = mp;
2721 	adapter->rx_desc_base[i].buffer_addr = htole64(paddr);
2722 	bus_dmamap_sync(adapter->rxtag, rx_buffer->map, BUS_DMASYNC_PREREAD);
2723 
2724 	return (0);
2725 }
2726 
2727 /*********************************************************************
2728  *
2729  *  Allocate memory for rx_buffer structures. Since we use one
2730  *  rx_buffer per received packet, the maximum number of rx_buffer's
2731  *  that we'll need is equal to the number of receive descriptors
2732  *  that we've allocated.
2733  *
2734  **********************************************************************/
2735 static int
2736 em_allocate_receive_structures(struct adapter *adapter)
2737 {
2738 	int i, error, size;
2739 	struct em_buffer *rx_buffer;
2740 
2741 	size = adapter->num_rx_desc * sizeof(struct em_buffer);
2742 	adapter->rx_buffer_area = kmalloc(size, M_DEVBUF, M_WAITOK | M_ZERO);
2743 
2744 	error = bus_dma_tag_create(NULL,		/* parent */
2745 				   1, 0,		/* alignment, bounds */
2746 				   BUS_SPACE_MAXADDR,	/* lowaddr */
2747 				   BUS_SPACE_MAXADDR,	/* highaddr */
2748 				   NULL, NULL,		/* filter, filterarg */
2749 				   MCLBYTES,		/* maxsize */
2750 				   1,			/* nsegments */
2751 				   MCLBYTES,		/* maxsegsize */
2752 				   0,			/* flags */
2753 				   &adapter->rxtag);
2754 	if (error) {
2755 		device_printf(adapter->dev, "%s: bus_dma_tag_create failed; "
2756 			      "error %u\n", __func__, error);
2757 		goto fail;
2758 	}
2759 
2760 	rx_buffer = adapter->rx_buffer_area;
2761 	for (i = 0; i < adapter->num_rx_desc; i++, rx_buffer++) {
2762 		error = bus_dmamap_create(adapter->rxtag, BUS_DMA_NOWAIT,
2763 					  &rx_buffer->map);
2764 		if (error) {
2765 			device_printf(adapter->dev,
2766 				      "%s: bus_dmamap_create failed; "
2767 				      "error %u\n", __func__, error);
2768 			goto fail;
2769 		}
2770 	}
2771 
2772 	for (i = 0; i < adapter->num_rx_desc; i++) {
2773 		error = em_get_buf(i, adapter, NULL, MB_WAIT);
2774 		if (error)
2775 			goto fail;
2776 	}
2777 
2778 	bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
2779 			BUS_DMASYNC_PREWRITE);
2780 
2781 	return (0);
2782 fail:
2783 	em_free_receive_structures(adapter);
2784 	return (error);
2785 }
2786 
2787 /*********************************************************************
2788  *
2789  *  Allocate and initialize receive structures.
2790  *
2791  **********************************************************************/
2792 static int
2793 em_setup_receive_structures(struct adapter *adapter)
2794 {
2795 	int error;
2796 
2797 	bzero(adapter->rx_desc_base,
2798 	      sizeof(struct em_rx_desc) * adapter->num_rx_desc);
2799 
2800 	error = em_allocate_receive_structures(adapter);
2801 	if (error)
2802 		return (error);
2803 
2804 	/* Setup our descriptor pointers */
2805 	adapter->next_rx_desc_to_check = 0;
2806 
2807 	return (0);
2808 }
2809 
2810 /*********************************************************************
2811  *
2812  *  Enable receive unit.
2813  *
2814  **********************************************************************/
2815 static void
2816 em_initialize_receive_unit(struct adapter *adapter)
2817 {
2818 	uint32_t reg_rctl;
2819 	uint32_t reg_rxcsum;
2820 	struct ifnet *ifp;
2821 	uint64_t bus_addr;
2822 
2823 	INIT_DEBUGOUT("em_initialize_receive_unit: begin");
2824 
2825 	ifp = &adapter->interface_data.ac_if;
2826 
2827 	/*
2828 	 * Make sure receives are disabled while setting
2829 	 * up the descriptor ring
2830 	 */
2831 	E1000_WRITE_REG(&adapter->hw, RCTL, 0);
2832 
2833 	/* Set the Receive Delay Timer Register */
2834 	E1000_WRITE_REG(&adapter->hw, RDTR,
2835 			adapter->rx_int_delay.value | E1000_RDT_FPDB);
2836 
2837 	if(adapter->hw.mac_type >= em_82540) {
2838 		E1000_WRITE_REG(&adapter->hw, RADV,
2839 				adapter->rx_abs_int_delay.value);
2840 
2841 		/* Set the interrupt throttling rate in 256ns increments */
2842 		if (em_int_throttle_ceil) {
2843 			E1000_WRITE_REG(&adapter->hw, ITR,
2844 				1000000000 / 256 / em_int_throttle_ceil);
2845 		} else {
2846 			E1000_WRITE_REG(&adapter->hw, ITR, 0);
2847 		}
2848 	}
2849 
2850 	/* Setup the Base and Length of the Rx Descriptor Ring */
2851 	bus_addr = adapter->rxdma.dma_paddr;
2852 	E1000_WRITE_REG(&adapter->hw, RDLEN, adapter->num_rx_desc *
2853 			sizeof(struct em_rx_desc));
2854 	E1000_WRITE_REG(&adapter->hw, RDBAH, (uint32_t)(bus_addr >> 32));
2855 	E1000_WRITE_REG(&adapter->hw, RDBAL, (uint32_t)bus_addr);
2856 
2857 	/* Setup the Receive Control Register */
2858 	reg_rctl = E1000_RCTL_EN | E1000_RCTL_BAM | E1000_RCTL_LBM_NO |
2859 		   E1000_RCTL_RDMTS_HALF |
2860 		   (adapter->hw.mc_filter_type << E1000_RCTL_MO_SHIFT);
2861 
2862 	if (adapter->hw.tbi_compatibility_on == TRUE)
2863 		reg_rctl |= E1000_RCTL_SBP;
2864 
2865 	switch (adapter->rx_buffer_len) {
2866 	default:
2867 	case EM_RXBUFFER_2048:
2868 		reg_rctl |= E1000_RCTL_SZ_2048;
2869 		break;
2870 	case EM_RXBUFFER_4096:
2871 		reg_rctl |= E1000_RCTL_SZ_4096 | E1000_RCTL_BSEX |
2872 			    E1000_RCTL_LPE;
2873 		break;
2874 	case EM_RXBUFFER_8192:
2875 		reg_rctl |= E1000_RCTL_SZ_8192 | E1000_RCTL_BSEX |
2876 			    E1000_RCTL_LPE;
2877 		break;
2878 	case EM_RXBUFFER_16384:
2879 		reg_rctl |= E1000_RCTL_SZ_16384 | E1000_RCTL_BSEX |
2880 			    E1000_RCTL_LPE;
2881 		break;
2882 	}
2883 
2884 	if (ifp->if_mtu > ETHERMTU)
2885 		reg_rctl |= E1000_RCTL_LPE;
2886 
2887 	/* Enable 82543 Receive Checksum Offload for TCP and UDP */
2888 	if ((adapter->hw.mac_type >= em_82543) &&
2889 	    (ifp->if_capenable & IFCAP_RXCSUM)) {
2890 		reg_rxcsum = E1000_READ_REG(&adapter->hw, RXCSUM);
2891 		reg_rxcsum |= (E1000_RXCSUM_IPOFL | E1000_RXCSUM_TUOFL);
2892 		E1000_WRITE_REG(&adapter->hw, RXCSUM, reg_rxcsum);
2893 	}
2894 
2895 #ifdef EM_X60_WORKAROUND
2896 	if (adapter->hw.mac_type == em_82573)
2897 		E1000_WRITE_REG(&adapter->hw, RDTR, 32);
2898 #endif
2899 
2900 	/* Enable Receives */
2901 	E1000_WRITE_REG(&adapter->hw, RCTL, reg_rctl);
2902 
2903 	/* Setup the HW Rx Head and Tail Descriptor Pointers */
2904 	E1000_WRITE_REG(&adapter->hw, RDH, 0);
2905 	E1000_WRITE_REG(&adapter->hw, RDT, adapter->num_rx_desc - 1);
2906 }
2907 
2908 /*********************************************************************
2909  *
2910  *  Free receive related data structures.
2911  *
2912  **********************************************************************/
2913 static void
2914 em_free_receive_structures(struct adapter *adapter)
2915 {
2916 	struct em_buffer *rx_buffer;
2917 	int i;
2918 
2919 	INIT_DEBUGOUT("free_receive_structures: begin");
2920 
2921 	if (adapter->rx_buffer_area != NULL) {
2922 		rx_buffer = adapter->rx_buffer_area;
2923 		for (i = 0; i < adapter->num_rx_desc; i++, rx_buffer++) {
2924 			if (rx_buffer->m_head != NULL) {
2925 				bus_dmamap_unload(adapter->rxtag,
2926 						  rx_buffer->map);
2927 				m_freem(rx_buffer->m_head);
2928 				rx_buffer->m_head = NULL;
2929 			}
2930 			if (rx_buffer->map != NULL) {
2931 				bus_dmamap_destroy(adapter->rxtag,
2932 						   rx_buffer->map);
2933 				rx_buffer->map = NULL;
2934 			}
2935 		}
2936 	}
2937 	if (adapter->rx_buffer_area != NULL) {
2938 		kfree(adapter->rx_buffer_area, M_DEVBUF);
2939 		adapter->rx_buffer_area = NULL;
2940 	}
2941 	if (adapter->rxtag != NULL) {
2942 		bus_dma_tag_destroy(adapter->rxtag);
2943 		adapter->rxtag = NULL;
2944 	}
2945 }
2946 
2947 /*********************************************************************
2948  *
2949  *  This routine executes in interrupt context. It replenishes
2950  *  the mbufs in the descriptor and sends data which has been
2951  *  dma'ed into host memory to upper layer.
2952  *
2953  *  We loop at most count times if count is > 0, or until done if
2954  *  count < 0.
2955  *
2956  *********************************************************************/
2957 static void
2958 em_rxeof(struct adapter *adapter, int count)
2959 {
2960 	struct ifnet *ifp;
2961 	struct mbuf *mp;
2962 	uint8_t accept_frame = 0;
2963 	uint8_t eop = 0;
2964 	uint16_t len, desc_len, prev_len_adj;
2965 	int i;
2966 
2967 	/* Pointer to the receive descriptor being examined. */
2968 	struct em_rx_desc *current_desc;
2969 
2970 	ifp = &adapter->interface_data.ac_if;
2971 	i = adapter->next_rx_desc_to_check;
2972 	current_desc = &adapter->rx_desc_base[i];
2973 
2974 	bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
2975 			BUS_DMASYNC_POSTREAD);
2976 
2977 	if (!(current_desc->status & E1000_RXD_STAT_DD))
2978 		return;
2979 
2980 	while ((current_desc->status & E1000_RXD_STAT_DD) && count != 0) {
2981 		logif(pkt_receive);
2982 		mp = adapter->rx_buffer_area[i].m_head;
2983 		bus_dmamap_sync(adapter->rxtag, adapter->rx_buffer_area[i].map,
2984 				BUS_DMASYNC_POSTREAD);
2985 		bus_dmamap_unload(adapter->rxtag,
2986 				  adapter->rx_buffer_area[i].map);
2987 
2988 		accept_frame = 1;
2989 		prev_len_adj = 0;
2990 		desc_len = le16toh(current_desc->length);
2991 		if (current_desc->status & E1000_RXD_STAT_EOP) {
2992 			count--;
2993 			eop = 1;
2994 			if (desc_len < ETHER_CRC_LEN) {
2995 				len = 0;
2996 				prev_len_adj = ETHER_CRC_LEN - desc_len;
2997 			} else {
2998 				len = desc_len - ETHER_CRC_LEN;
2999 			}
3000 		} else {
3001 			eop = 0;
3002 			len = desc_len;
3003 		}
3004 
3005 		if (current_desc->errors & E1000_RXD_ERR_FRAME_ERR_MASK) {
3006 			uint8_t last_byte;
3007 			uint32_t pkt_len = desc_len;
3008 
3009 			if (adapter->fmp != NULL)
3010 				pkt_len += adapter->fmp->m_pkthdr.len;
3011 
3012 			last_byte = *(mtod(mp, caddr_t) + desc_len - 1);
3013 
3014 			if (TBI_ACCEPT(&adapter->hw, current_desc->status,
3015 				       current_desc->errors,
3016 				       pkt_len, last_byte)) {
3017 				em_tbi_adjust_stats(&adapter->hw,
3018 						    &adapter->stats,
3019 						    pkt_len,
3020 						    adapter->hw.mac_addr);
3021 				if (len > 0)
3022 					len--;
3023 			} else {
3024 				accept_frame = 0;
3025 			}
3026 		}
3027 
3028 		if (accept_frame) {
3029 			if (em_get_buf(i, adapter, NULL, MB_DONTWAIT) == ENOBUFS) {
3030 				adapter->dropped_pkts++;
3031 				em_get_buf(i, adapter, mp, MB_DONTWAIT);
3032 				if (adapter->fmp != NULL)
3033 					m_freem(adapter->fmp);
3034 				adapter->fmp = NULL;
3035 				adapter->lmp = NULL;
3036 				goto skip;
3037 			}
3038 
3039 			/* Assign correct length to the current fragment */
3040 			mp->m_len = len;
3041 
3042 			if (adapter->fmp == NULL) {
3043 				mp->m_pkthdr.len = len;
3044 				adapter->fmp = mp;	 /* Store the first mbuf */
3045 				adapter->lmp = mp;
3046 			} else {
3047 				/* Chain mbuf's together */
3048 				/*
3049 				 * Adjust length of previous mbuf in chain if
3050 				 * we received less than 4 bytes in the last
3051 				 * descriptor.
3052 				 */
3053 				if (prev_len_adj > 0) {
3054 					adapter->lmp->m_len -= prev_len_adj;
3055 					adapter->fmp->m_pkthdr.len -= prev_len_adj;
3056 				}
3057 				adapter->lmp->m_next = mp;
3058 				adapter->lmp = adapter->lmp->m_next;
3059 				adapter->fmp->m_pkthdr.len += len;
3060 			}
3061 
3062 			if (eop) {
3063 				adapter->fmp->m_pkthdr.rcvif = ifp;
3064 				ifp->if_ipackets++;
3065 
3066 				em_receive_checksum(adapter, current_desc,
3067 						    adapter->fmp);
3068 				if (current_desc->status & E1000_RXD_STAT_VP) {
3069 					VLAN_INPUT_TAG(adapter->fmp,
3070 						       (current_desc->special &
3071 							E1000_RXD_SPC_VLAN_MASK));
3072 				} else {
3073 					ifp->if_input(ifp, adapter->fmp);
3074 				}
3075 				adapter->fmp = NULL;
3076 				adapter->lmp = NULL;
3077 			}
3078 		} else {
3079 			adapter->dropped_pkts++;
3080 			em_get_buf(i, adapter, mp, MB_DONTWAIT);
3081 			if (adapter->fmp != NULL)
3082 				m_freem(adapter->fmp);
3083 			adapter->fmp = NULL;
3084 			adapter->lmp = NULL;
3085 		}
3086 
3087 skip:
3088 		/* Zero out the receive descriptors status. */
3089 		current_desc->status = 0;
3090 
3091 		/* Advance our pointers to the next descriptor. */
3092 		if (++i == adapter->num_rx_desc) {
3093 			i = 0;
3094 			current_desc = adapter->rx_desc_base;
3095 		} else {
3096 			current_desc++;
3097 		}
3098 	}
3099 
3100 	bus_dmamap_sync(adapter->rxdma.dma_tag, adapter->rxdma.dma_map,
3101 			BUS_DMASYNC_PREWRITE);
3102 
3103 	adapter->next_rx_desc_to_check = i;
3104 
3105 	/* Advance the E1000's Receive Queue #0  "Tail Pointer". */
3106 	if (--i < 0)
3107 		i = adapter->num_rx_desc - 1;
3108 
3109 	E1000_WRITE_REG(&adapter->hw, RDT, i);
3110 }
3111 
3112 /*********************************************************************
3113  *
3114  *  Verify that the hardware indicated that the checksum is valid.
3115  *  Inform the stack about the status of checksum so that stack
3116  *  doesn't spend time verifying the checksum.
3117  *
3118  *********************************************************************/
3119 static void
3120 em_receive_checksum(struct adapter *adapter,
3121 		    struct em_rx_desc *rx_desc,
3122 		    struct mbuf *mp)
3123 {
3124 	/* 82543 or newer only */
3125 	if ((adapter->hw.mac_type < em_82543) ||
3126 	    /* Ignore Checksum bit is set */
3127 	    (rx_desc->status & E1000_RXD_STAT_IXSM)) {
3128 		mp->m_pkthdr.csum_flags = 0;
3129 		return;
3130 	}
3131 
3132 	if (rx_desc->status & E1000_RXD_STAT_IPCS) {
3133 		/* Did it pass? */
3134 		if (!(rx_desc->errors & E1000_RXD_ERR_IPE)) {
3135 			/* IP Checksum Good */
3136 			mp->m_pkthdr.csum_flags = CSUM_IP_CHECKED;
3137 			mp->m_pkthdr.csum_flags |= CSUM_IP_VALID;
3138 		} else {
3139 			mp->m_pkthdr.csum_flags = 0;
3140 		}
3141 	}
3142 
3143 	if (rx_desc->status & E1000_RXD_STAT_TCPCS) {
3144 		/* Did it pass? */
3145 		if (!(rx_desc->errors & E1000_RXD_ERR_TCPE)) {
3146 			mp->m_pkthdr.csum_flags |=
3147 			(CSUM_DATA_VALID | CSUM_PSEUDO_HDR);
3148 			mp->m_pkthdr.csum_data = htons(0xffff);
3149 		}
3150 	}
3151 }
3152 
3153 
3154 static void
3155 em_enable_vlans(struct adapter *adapter)
3156 {
3157 	uint32_t ctrl;
3158 
3159 	E1000_WRITE_REG(&adapter->hw, VET, ETHERTYPE_VLAN);
3160 
3161 	ctrl = E1000_READ_REG(&adapter->hw, CTRL);
3162 	ctrl |= E1000_CTRL_VME;
3163 	E1000_WRITE_REG(&adapter->hw, CTRL, ctrl);
3164 }
3165 
3166 static void
3167 em_disable_vlans(struct adapter *adapter)
3168 {
3169 	uint32_t ctrl;
3170 
3171 	ctrl = E1000_READ_REG(&adapter->hw, CTRL);
3172 	ctrl &= ~E1000_CTRL_VME;
3173 	E1000_WRITE_REG(&adapter->hw, CTRL, ctrl);
3174 }
3175 
3176 /*
3177  * note: we must call bus_enable_intr() prior to enabling the hardware
3178  * interrupt and bus_disable_intr() after disabling the hardware interrupt
3179  * in order to avoid handler execution races from scheduled interrupt
3180  * threads.
3181  */
3182 static void
3183 em_enable_intr(struct adapter *adapter)
3184 {
3185 	struct ifnet *ifp = &adapter->interface_data.ac_if;
3186 
3187 	if ((ifp->if_flags & IFF_POLLING) == 0) {
3188 		lwkt_serialize_handler_enable(ifp->if_serializer);
3189 		E1000_WRITE_REG(&adapter->hw, IMS, (IMS_ENABLE_MASK));
3190 	}
3191 }
3192 
3193 static void
3194 em_disable_intr(struct adapter *adapter)
3195 {
3196 	/*
3197 	 * The first version of 82542 had an errata where when link was forced
3198 	 * it would stay up even up even if the cable was disconnected.
3199 	 * Sequence errors were used to detect the disconnect and then the
3200 	 * driver would unforce the link.  This code in the in the ISR.  For
3201 	 * this to work correctly the Sequence error interrupt had to be
3202 	 * enabled all the time.
3203 	 */
3204 	if (adapter->hw.mac_type == em_82542_rev2_0) {
3205 		E1000_WRITE_REG(&adapter->hw, IMC,
3206 				(0xffffffff & ~E1000_IMC_RXSEQ));
3207 	} else {
3208 		E1000_WRITE_REG(&adapter->hw, IMC, 0xffffffff);
3209 	}
3210 
3211 	lwkt_serialize_handler_disable(adapter->interface_data.ac_if.if_serializer);
3212 }
3213 
3214 static int
3215 em_is_valid_ether_addr(uint8_t *addr)
3216 {
3217 	static const char zero_addr[6] = { 0, 0, 0, 0, 0, 0 };
3218 
3219 	if ((addr[0] & 1) || !bcmp(addr, zero_addr, ETHER_ADDR_LEN))
3220 		return (FALSE);
3221 	else
3222 		return (TRUE);
3223 }
3224 
3225 void
3226 em_write_pci_cfg(struct em_hw *hw, uint32_t reg, uint16_t *value)
3227 {
3228 	pci_write_config(((struct em_osdep *)hw->back)->dev, reg, *value, 2);
3229 }
3230 
3231 void
3232 em_read_pci_cfg(struct em_hw *hw, uint32_t reg, uint16_t *value)
3233 {
3234 	*value = pci_read_config(((struct em_osdep *)hw->back)->dev, reg, 2);
3235 }
3236 
3237 void
3238 em_pci_set_mwi(struct em_hw *hw)
3239 {
3240 	pci_write_config(((struct em_osdep *)hw->back)->dev, PCIR_COMMAND,
3241 			 (hw->pci_cmd_word | CMD_MEM_WRT_INVALIDATE), 2);
3242 }
3243 
3244 void
3245 em_pci_clear_mwi(struct em_hw *hw)
3246 {
3247 	pci_write_config(((struct em_osdep *)hw->back)->dev, PCIR_COMMAND,
3248 			 (hw->pci_cmd_word & ~CMD_MEM_WRT_INVALIDATE), 2);
3249 }
3250 
3251 uint32_t
3252 em_io_read(struct em_hw *hw, unsigned long port)
3253 {
3254 	struct em_osdep *io = hw->back;
3255 
3256 	return bus_space_read_4(io->io_bus_space_tag,
3257 				io->io_bus_space_handle, port);
3258 }
3259 
3260 void
3261 em_io_write(struct em_hw *hw, unsigned long port, uint32_t value)
3262 {
3263 	struct em_osdep *io = hw->back;
3264 
3265 	bus_space_write_4(io->io_bus_space_tag,
3266 			  io->io_bus_space_handle, port, value);
3267 }
3268 
3269 /*
3270  * We may eventually really do this, but its unnecessary
3271  * for now so we just return unsupported.
3272  */
3273 int32_t
3274 em_read_pcie_cap_reg(struct em_hw *hw, uint32_t reg, uint16_t *value)
3275 {
3276 	return (0);
3277 }
3278 
3279 
3280 /*********************************************************************
3281  * 82544 Coexistence issue workaround.
3282  *    There are 2 issues.
3283  *	1. Transmit Hang issue.
3284  *    To detect this issue, following equation can be used...
3285  *          SIZE[3:0] + ADDR[2:0] = SUM[3:0].
3286  *          If SUM[3:0] is in between 1 to 4, we will have this issue.
3287  *
3288  *	2. DAC issue.
3289  *    To detect this issue, following equation can be used...
3290  *          SIZE[3:0] + ADDR[2:0] = SUM[3:0].
3291  *          If SUM[3:0] is in between 9 to c, we will have this issue.
3292  *
3293  *
3294  *    WORKAROUND:
3295  *          Make sure we do not have ending address as 1,2,3,4(Hang) or
3296  *          9,a,b,c (DAC)
3297  *
3298 *************************************************************************/
3299 static uint32_t
3300 em_fill_descriptors(bus_addr_t address, uint32_t length, PDESC_ARRAY desc_array)
3301 {
3302 	/* Since issue is sensitive to length and address.*/
3303 	/* Let us first check the address...*/
3304 	uint32_t safe_terminator;
3305 	if (length <= 4) {
3306 		desc_array->descriptor[0].address = address;
3307 		desc_array->descriptor[0].length = length;
3308 		desc_array->elements = 1;
3309 		return (desc_array->elements);
3310 	}
3311 	safe_terminator = (uint32_t)((((uint32_t)address & 0x7) + (length & 0xF)) & 0xF);
3312 	/* if it does not fall between 0x1 to 0x4 and 0x9 to 0xC then return */
3313 	if (safe_terminator == 0 ||
3314 	    (safe_terminator > 4 && safe_terminator < 9) ||
3315 	    (safe_terminator > 0xC && safe_terminator <= 0xF)) {
3316 		desc_array->descriptor[0].address = address;
3317 		desc_array->descriptor[0].length = length;
3318 		desc_array->elements = 1;
3319 		return (desc_array->elements);
3320 	}
3321 
3322 	desc_array->descriptor[0].address = address;
3323 	desc_array->descriptor[0].length = length - 4;
3324 	desc_array->descriptor[1].address = address + (length - 4);
3325 	desc_array->descriptor[1].length = 4;
3326 	desc_array->elements = 2;
3327 	return (desc_array->elements);
3328 }
3329 
3330 /**********************************************************************
3331  *
3332  *  Update the board statistics counters.
3333  *
3334  **********************************************************************/
3335 static void
3336 em_update_stats_counters(struct adapter *adapter)
3337 {
3338 	struct ifnet   *ifp;
3339 
3340 	if (adapter->hw.media_type == em_media_type_copper ||
3341 	    (E1000_READ_REG(&adapter->hw, STATUS) & E1000_STATUS_LU)) {
3342 		adapter->stats.symerrs += E1000_READ_REG(&adapter->hw, SYMERRS);
3343 		adapter->stats.sec += E1000_READ_REG(&adapter->hw, SEC);
3344 	}
3345 	adapter->stats.crcerrs += E1000_READ_REG(&adapter->hw, CRCERRS);
3346 	adapter->stats.mpc += E1000_READ_REG(&adapter->hw, MPC);
3347 	adapter->stats.scc += E1000_READ_REG(&adapter->hw, SCC);
3348 	adapter->stats.ecol += E1000_READ_REG(&adapter->hw, ECOL);
3349 
3350 	adapter->stats.mcc += E1000_READ_REG(&adapter->hw, MCC);
3351 	adapter->stats.latecol += E1000_READ_REG(&adapter->hw, LATECOL);
3352 	adapter->stats.colc += E1000_READ_REG(&adapter->hw, COLC);
3353 	adapter->stats.dc += E1000_READ_REG(&adapter->hw, DC);
3354 	adapter->stats.rlec += E1000_READ_REG(&adapter->hw, RLEC);
3355 	adapter->stats.xonrxc += E1000_READ_REG(&adapter->hw, XONRXC);
3356 	adapter->stats.xontxc += E1000_READ_REG(&adapter->hw, XONTXC);
3357 	adapter->stats.xoffrxc += E1000_READ_REG(&adapter->hw, XOFFRXC);
3358 	adapter->stats.xofftxc += E1000_READ_REG(&adapter->hw, XOFFTXC);
3359 	adapter->stats.fcruc += E1000_READ_REG(&adapter->hw, FCRUC);
3360 	adapter->stats.prc64 += E1000_READ_REG(&adapter->hw, PRC64);
3361 	adapter->stats.prc127 += E1000_READ_REG(&adapter->hw, PRC127);
3362 	adapter->stats.prc255 += E1000_READ_REG(&adapter->hw, PRC255);
3363 	adapter->stats.prc511 += E1000_READ_REG(&adapter->hw, PRC511);
3364 	adapter->stats.prc1023 += E1000_READ_REG(&adapter->hw, PRC1023);
3365 	adapter->stats.prc1522 += E1000_READ_REG(&adapter->hw, PRC1522);
3366 	adapter->stats.gprc += E1000_READ_REG(&adapter->hw, GPRC);
3367 	adapter->stats.bprc += E1000_READ_REG(&adapter->hw, BPRC);
3368 	adapter->stats.mprc += E1000_READ_REG(&adapter->hw, MPRC);
3369 	adapter->stats.gptc += E1000_READ_REG(&adapter->hw, GPTC);
3370 
3371 	/* For the 64-bit byte counters the low dword must be read first. */
3372 	/* Both registers clear on the read of the high dword */
3373 
3374 	adapter->stats.gorcl += E1000_READ_REG(&adapter->hw, GORCL);
3375 	adapter->stats.gorch += E1000_READ_REG(&adapter->hw, GORCH);
3376 	adapter->stats.gotcl += E1000_READ_REG(&adapter->hw, GOTCL);
3377 	adapter->stats.gotch += E1000_READ_REG(&adapter->hw, GOTCH);
3378 
3379 	adapter->stats.rnbc += E1000_READ_REG(&adapter->hw, RNBC);
3380 	adapter->stats.ruc += E1000_READ_REG(&adapter->hw, RUC);
3381 	adapter->stats.rfc += E1000_READ_REG(&adapter->hw, RFC);
3382 	adapter->stats.roc += E1000_READ_REG(&adapter->hw, ROC);
3383 	adapter->stats.rjc += E1000_READ_REG(&adapter->hw, RJC);
3384 
3385 	adapter->stats.torl += E1000_READ_REG(&adapter->hw, TORL);
3386 	adapter->stats.torh += E1000_READ_REG(&adapter->hw, TORH);
3387 	adapter->stats.totl += E1000_READ_REG(&adapter->hw, TOTL);
3388 	adapter->stats.toth += E1000_READ_REG(&adapter->hw, TOTH);
3389 
3390 	adapter->stats.tpr += E1000_READ_REG(&adapter->hw, TPR);
3391 	adapter->stats.tpt += E1000_READ_REG(&adapter->hw, TPT);
3392 	adapter->stats.ptc64 += E1000_READ_REG(&adapter->hw, PTC64);
3393 	adapter->stats.ptc127 += E1000_READ_REG(&adapter->hw, PTC127);
3394 	adapter->stats.ptc255 += E1000_READ_REG(&adapter->hw, PTC255);
3395 	adapter->stats.ptc511 += E1000_READ_REG(&adapter->hw, PTC511);
3396 	adapter->stats.ptc1023 += E1000_READ_REG(&adapter->hw, PTC1023);
3397 	adapter->stats.ptc1522 += E1000_READ_REG(&adapter->hw, PTC1522);
3398 	adapter->stats.mptc += E1000_READ_REG(&adapter->hw, MPTC);
3399 	adapter->stats.bptc += E1000_READ_REG(&adapter->hw, BPTC);
3400 
3401 	if (adapter->hw.mac_type >= em_82543) {
3402 		adapter->stats.algnerrc +=
3403 		    E1000_READ_REG(&adapter->hw, ALGNERRC);
3404 		adapter->stats.rxerrc +=
3405 		    E1000_READ_REG(&adapter->hw, RXERRC);
3406 		adapter->stats.tncrs +=
3407 		    E1000_READ_REG(&adapter->hw, TNCRS);
3408 		adapter->stats.cexterr +=
3409 		    E1000_READ_REG(&adapter->hw, CEXTERR);
3410 		adapter->stats.tsctc +=
3411 		    E1000_READ_REG(&adapter->hw, TSCTC);
3412 		adapter->stats.tsctfc +=
3413 		    E1000_READ_REG(&adapter->hw, TSCTFC);
3414 	}
3415 	ifp = &adapter->interface_data.ac_if;
3416 
3417 	/* Fill out the OS statistics structure */
3418 	ifp->if_collisions = adapter->stats.colc;
3419 
3420 	/* Rx Errors */
3421 	ifp->if_ierrors =
3422 		adapter->dropped_pkts +
3423 		adapter->stats.rxerrc +
3424 		adapter->stats.crcerrs +
3425 		adapter->stats.algnerrc +
3426 		adapter->stats.ruc + adapter->stats.roc +
3427 		adapter->stats.mpc + adapter->stats.cexterr +
3428 		adapter->rx_overruns;
3429 
3430 	/* Tx Errors */
3431 	ifp->if_oerrors = adapter->stats.ecol + adapter->stats.latecol +
3432 			  adapter->watchdog_timeouts;
3433 }
3434 
3435 
3436 /**********************************************************************
3437  *
3438  *  This routine is called only when em_display_debug_stats is enabled.
3439  *  This routine provides a way to take a look at important statistics
3440  *  maintained by the driver and hardware.
3441  *
3442  **********************************************************************/
3443 static void
3444 em_print_debug_info(struct adapter *adapter)
3445 {
3446 	device_t dev= adapter->dev;
3447 	uint8_t *hw_addr = adapter->hw.hw_addr;
3448 
3449 	device_printf(dev, "Adapter hardware address = %p \n", hw_addr);
3450 	device_printf(dev, "CTRL  = 0x%x RCTL = 0x%x\n",
3451 		      E1000_READ_REG(&adapter->hw, CTRL),
3452 		      E1000_READ_REG(&adapter->hw, RCTL));
3453 	device_printf(dev, "Packet buffer = Tx=%dk Rx=%dk\n",
3454 		      ((E1000_READ_REG(&adapter->hw, PBA) & 0xffff0000) >> 16),
3455 		      (E1000_READ_REG(&adapter->hw, PBA) & 0xffff));
3456 	device_printf(dev, "Flow control watermarks high = %d low = %d\n",
3457 		      adapter->hw.fc_high_water, adapter->hw.fc_low_water);
3458 	device_printf(dev, "tx_int_delay = %d, tx_abs_int_delay = %d\n",
3459 		      E1000_READ_REG(&adapter->hw, TIDV),
3460 		      E1000_READ_REG(&adapter->hw, TADV));
3461 	device_printf(dev, "rx_int_delay = %d, rx_abs_int_delay = %d\n",
3462 		      E1000_READ_REG(&adapter->hw, RDTR),
3463 		      E1000_READ_REG(&adapter->hw, RADV));
3464 	device_printf(dev, "fifo workaround = %lld, fifo_reset_count = %lld\n",
3465 		      (long long)adapter->tx_fifo_wrk_cnt,
3466 		      (long long)adapter->tx_fifo_reset_cnt);
3467 	device_printf(dev, "hw tdh = %d, hw tdt = %d\n",
3468 		      E1000_READ_REG(&adapter->hw, TDH),
3469 		      E1000_READ_REG(&adapter->hw, TDT));
3470 	device_printf(dev, "Num Tx descriptors avail = %d\n",
3471 		      adapter->num_tx_desc_avail);
3472 	device_printf(dev, "Tx Descriptors not avail1 = %ld\n",
3473 		      adapter->no_tx_desc_avail1);
3474 	device_printf(dev, "Tx Descriptors not avail2 = %ld\n",
3475 		      adapter->no_tx_desc_avail2);
3476 	device_printf(dev, "Std mbuf failed = %ld\n",
3477 		      adapter->mbuf_alloc_failed);
3478 	device_printf(dev, "Std mbuf cluster failed = %ld\n",
3479 		      adapter->mbuf_cluster_failed);
3480 	device_printf(dev, "Driver dropped packets = %ld\n",
3481 		      adapter->dropped_pkts);
3482 }
3483 
3484 static void
3485 em_print_hw_stats(struct adapter *adapter)
3486 {
3487 	device_t dev= adapter->dev;
3488 
3489 	device_printf(dev, "Excessive collisions = %lld\n",
3490 		      (long long)adapter->stats.ecol);
3491 	device_printf(dev, "Symbol errors = %lld\n",
3492 		      (long long)adapter->stats.symerrs);
3493 	device_printf(dev, "Sequence errors = %lld\n",
3494 		      (long long)adapter->stats.sec);
3495 	device_printf(dev, "Defer count = %lld\n",
3496 		      (long long)adapter->stats.dc);
3497 
3498 	device_printf(dev, "Missed Packets = %lld\n",
3499 		      (long long)adapter->stats.mpc);
3500 	device_printf(dev, "Receive No Buffers = %lld\n",
3501 		      (long long)adapter->stats.rnbc);
3502 	/* RLEC is inaccurate on some hardware, calculate our own. */
3503 	device_printf(dev, "Receive Length errors = %lld\n",
3504 		      (long long)adapter->stats.roc +
3505 		      (long long)adapter->stats.ruc);
3506 	device_printf(dev, "Receive errors = %lld\n",
3507 		      (long long)adapter->stats.rxerrc);
3508 	device_printf(dev, "Crc errors = %lld\n",
3509 		      (long long)adapter->stats.crcerrs);
3510 	device_printf(dev, "Alignment errors = %lld\n",
3511 		      (long long)adapter->stats.algnerrc);
3512 	device_printf(dev, "Carrier extension errors = %lld\n",
3513 		      (long long)adapter->stats.cexterr);
3514 	device_printf(dev, "RX overruns = %lu\n", adapter->rx_overruns);
3515 	device_printf(dev, "Watchdog timeouts = %lu\n",
3516 		      adapter->watchdog_timeouts);
3517 
3518 	device_printf(dev, "XON Rcvd = %lld\n",
3519 		      (long long)adapter->stats.xonrxc);
3520 	device_printf(dev, "XON Xmtd = %lld\n",
3521 		      (long long)adapter->stats.xontxc);
3522 	device_printf(dev, "XOFF Rcvd = %lld\n",
3523 		      (long long)adapter->stats.xoffrxc);
3524 	device_printf(dev, "XOFF Xmtd = %lld\n",
3525 		      (long long)adapter->stats.xofftxc);
3526 
3527 	device_printf(dev, "Good Packets Rcvd = %lld\n",
3528 		      (long long)adapter->stats.gprc);
3529 	device_printf(dev, "Good Packets Xmtd = %lld\n",
3530 		      (long long)adapter->stats.gptc);
3531 }
3532 
3533 static int
3534 em_sysctl_debug_info(SYSCTL_HANDLER_ARGS)
3535 {
3536 	int error;
3537 	int result;
3538 	struct adapter *adapter;
3539 
3540 	result = -1;
3541 	error = sysctl_handle_int(oidp, &result, 0, req);
3542 
3543 	if (error || !req->newptr)
3544 		return (error);
3545 
3546 	if (result == 1) {
3547 		adapter = (struct adapter *)arg1;
3548 		em_print_debug_info(adapter);
3549 	}
3550 
3551 	return (error);
3552 }
3553 
3554 static int
3555 em_sysctl_stats(SYSCTL_HANDLER_ARGS)
3556 {
3557 	int error;
3558 	int result;
3559 	struct adapter *adapter;
3560 
3561 	result = -1;
3562 	error = sysctl_handle_int(oidp, &result, 0, req);
3563 
3564 	if (error || !req->newptr)
3565 		return (error);
3566 
3567 	if (result == 1) {
3568 		adapter = (struct adapter *)arg1;
3569 		em_print_hw_stats(adapter);
3570 	}
3571 
3572 	return (error);
3573 }
3574 
3575 static int
3576 em_sysctl_int_delay(SYSCTL_HANDLER_ARGS)
3577 {
3578 	struct em_int_delay_info *info;
3579 	struct adapter *adapter;
3580 	uint32_t regval;
3581 	int error;
3582 	int usecs;
3583 	int ticks;
3584 
3585 	info = (struct em_int_delay_info *)arg1;
3586 	adapter = info->adapter;
3587 	usecs = info->value;
3588 	error = sysctl_handle_int(oidp, &usecs, 0, req);
3589 	if (error != 0 || req->newptr == NULL)
3590 		return (error);
3591 	if (usecs < 0 || usecs > E1000_TICKS_TO_USECS(65535))
3592 		return (EINVAL);
3593 	info->value = usecs;
3594 	ticks = E1000_USECS_TO_TICKS(usecs);
3595 
3596 	lwkt_serialize_enter(adapter->interface_data.ac_if.if_serializer);
3597 	regval = E1000_READ_OFFSET(&adapter->hw, info->offset);
3598 	regval = (regval & ~0xffff) | (ticks & 0xffff);
3599 	/* Handle a few special cases. */
3600 	switch (info->offset) {
3601 	case E1000_RDTR:
3602 	case E1000_82542_RDTR:
3603 		regval |= E1000_RDT_FPDB;
3604 		break;
3605 	case E1000_TIDV:
3606 	case E1000_82542_TIDV:
3607 		if (ticks == 0) {
3608 			adapter->txd_cmd &= ~E1000_TXD_CMD_IDE;
3609 			/* Don't write 0 into the TIDV register. */
3610 			regval++;
3611 		} else
3612 			adapter->txd_cmd |= E1000_TXD_CMD_IDE;
3613 		break;
3614 	}
3615 	E1000_WRITE_OFFSET(&adapter->hw, info->offset, regval);
3616 	lwkt_serialize_exit(adapter->interface_data.ac_if.if_serializer);
3617 	return (0);
3618 }
3619 
3620 static void
3621 em_add_int_delay_sysctl(struct adapter *adapter, const char *name,
3622 			const char *description, struct em_int_delay_info *info,
3623 			int offset, int value)
3624 {
3625 	info->adapter = adapter;
3626 	info->offset = offset;
3627 	info->value = value;
3628 	SYSCTL_ADD_PROC(&adapter->sysctl_ctx,
3629 			SYSCTL_CHILDREN(adapter->sysctl_tree),
3630 			OID_AUTO, name, CTLTYPE_INT|CTLFLAG_RW,
3631 			info, 0, em_sysctl_int_delay, "I", description);
3632 }
3633 
3634 static int
3635 em_sysctl_int_throttle(SYSCTL_HANDLER_ARGS)
3636 {
3637 	struct adapter *adapter = (void *)arg1;
3638 	int error;
3639 	int throttle;
3640 
3641 	throttle = em_int_throttle_ceil;
3642 	error = sysctl_handle_int(oidp, &throttle, 0, req);
3643 	if (error || req->newptr == NULL)
3644 		return error;
3645 	if (throttle < 0 || throttle > 1000000000 / 256)
3646 		return EINVAL;
3647 	if (throttle) {
3648 		/*
3649 		 * Set the interrupt throttling rate in 256ns increments,
3650 		 * recalculate sysctl value assignment to get exact frequency.
3651 		 */
3652 		throttle = 1000000000 / 256 / throttle;
3653 		lwkt_serialize_enter(adapter->interface_data.ac_if.if_serializer);
3654 		em_int_throttle_ceil = 1000000000 / 256 / throttle;
3655 		E1000_WRITE_REG(&adapter->hw, ITR, throttle);
3656 		lwkt_serialize_exit(adapter->interface_data.ac_if.if_serializer);
3657 	} else {
3658 		lwkt_serialize_enter(adapter->interface_data.ac_if.if_serializer);
3659 		em_int_throttle_ceil = 0;
3660 		E1000_WRITE_REG(&adapter->hw, ITR, 0);
3661 		lwkt_serialize_exit(adapter->interface_data.ac_if.if_serializer);
3662 	}
3663 	device_printf(adapter->dev, "Interrupt moderation set to %d/sec\n",
3664 			em_int_throttle_ceil);
3665 	return 0;
3666 }
3667