xref: /titanic_50/usr/src/uts/common/io/nxge/nxge_send.c (revision 689d74b0a0dba643450e7fc74a03425c963657e7)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 #include <sys/nxge/nxge_impl.h>
29 #include <sys/nxge/nxge_hio.h>
30 #include <npi_tx_wr64.h>
31 
32 /* Software LSO required header files */
33 #include <netinet/tcp.h>
34 #include <inet/ip_impl.h>
35 #include <inet/tcp.h>
36 
37 static mblk_t *nxge_lso_eliminate(mblk_t *);
38 static mblk_t *nxge_do_softlso(mblk_t *mp, uint32_t mss);
39 static void nxge_lso_info_get(mblk_t *, uint32_t *, uint32_t *);
40 static void nxge_hcksum_retrieve(mblk_t *,
41     uint32_t *, uint32_t *, uint32_t *,
42     uint32_t *, uint32_t *);
43 static uint32_t nxge_csgen(uint16_t *, int);
44 
45 extern uint32_t		nxge_reclaim_pending;
46 extern uint32_t 	nxge_bcopy_thresh;
47 extern uint32_t 	nxge_dvma_thresh;
48 extern uint32_t 	nxge_dma_stream_thresh;
49 extern uint32_t		nxge_tx_minfree;
50 extern uint32_t		nxge_tx_intr_thres;
51 extern uint32_t		nxge_tx_max_gathers;
52 extern uint32_t		nxge_tx_tiny_pack;
53 extern uint32_t		nxge_tx_use_bcopy;
54 extern uint32_t		nxge_tx_lb_policy;
55 extern uint32_t		nxge_no_tx_lb;
56 extern nxge_tx_mode_t	nxge_tx_scheme;
57 uint32_t		nxge_lso_kick_cnt = 2;
58 
59 typedef struct _mac_tx_hint {
60 	uint16_t	sap;
61 	uint16_t	vid;
62 	void		*hash;
63 } mac_tx_hint_t, *p_mac_tx_hint_t;
64 
65 int nxge_tx_lb_ring_1(p_mblk_t, uint32_t, p_mac_tx_hint_t);
66 
67 int
68 nxge_start(p_nxge_t nxgep, p_tx_ring_t tx_ring_p, p_mblk_t mp)
69 {
70 	int 			status = 0;
71 	p_tx_desc_t 		tx_desc_ring_vp;
72 	npi_handle_t		npi_desc_handle;
73 	nxge_os_dma_handle_t 	tx_desc_dma_handle;
74 	p_tx_desc_t 		tx_desc_p;
75 	p_tx_msg_t 		tx_msg_ring;
76 	p_tx_msg_t 		tx_msg_p;
77 	tx_desc_t		tx_desc, *tmp_desc_p;
78 	tx_desc_t		sop_tx_desc, *sop_tx_desc_p;
79 	p_tx_pkt_header_t	hdrp;
80 	tx_pkt_header_t		tmp_hdrp;
81 	p_tx_pkt_hdr_all_t	pkthdrp;
82 	uint8_t			npads = 0;
83 	uint64_t 		dma_ioaddr;
84 	uint32_t		dma_flags;
85 	int			last_bidx;
86 	uint8_t 		*b_rptr;
87 	caddr_t 		kaddr;
88 	uint32_t		nmblks;
89 	uint32_t		ngathers;
90 	uint32_t		clen;
91 	int 			len;
92 	uint32_t		pkt_len, pack_len, min_len;
93 	uint32_t		bcopy_thresh;
94 	int 			i, cur_index, sop_index;
95 	uint16_t		tail_index;
96 	boolean_t		tail_wrap = B_FALSE;
97 	nxge_dma_common_t	desc_area;
98 	nxge_os_dma_handle_t 	dma_handle;
99 	ddi_dma_cookie_t 	dma_cookie;
100 	npi_handle_t		npi_handle;
101 	p_mblk_t 		nmp;
102 	p_mblk_t		t_mp;
103 	uint32_t 		ncookies;
104 	boolean_t 		good_packet;
105 	boolean_t 		mark_mode = B_FALSE;
106 	p_nxge_stats_t 		statsp;
107 	p_nxge_tx_ring_stats_t tdc_stats;
108 	t_uscalar_t 		start_offset = 0;
109 	t_uscalar_t 		stuff_offset = 0;
110 	t_uscalar_t 		end_offset = 0;
111 	t_uscalar_t 		value = 0;
112 	t_uscalar_t 		cksum_flags = 0;
113 	boolean_t		cksum_on = B_FALSE;
114 	uint32_t		boff = 0;
115 	uint64_t		tot_xfer_len = 0;
116 	boolean_t		header_set = B_FALSE;
117 #ifdef NXGE_DEBUG
118 	p_tx_desc_t 		tx_desc_ring_pp;
119 	p_tx_desc_t 		tx_desc_pp;
120 	tx_desc_t		*save_desc_p;
121 	int			dump_len;
122 	int			sad_len;
123 	uint64_t		sad;
124 	int			xfer_len;
125 	uint32_t		msgsize;
126 #endif
127 	p_mblk_t 		mp_chain = NULL;
128 	boolean_t		is_lso = B_FALSE;
129 	boolean_t		lso_again;
130 	int			cur_index_lso;
131 	p_mblk_t 		nmp_lso_save;
132 	uint32_t		lso_ngathers;
133 	boolean_t		lso_tail_wrap = B_FALSE;
134 
135 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
136 	    "==> nxge_start: tx dma channel %d", tx_ring_p->tdc));
137 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
138 	    "==> nxge_start: Starting tdc %d desc pending %d",
139 	    tx_ring_p->tdc, tx_ring_p->descs_pending));
140 
141 	statsp = nxgep->statsp;
142 
143 	if (!isLDOMguest(nxgep)) {
144 		switch (nxgep->mac.portmode) {
145 		default:
146 			if (nxgep->statsp->port_stats.lb_mode ==
147 			    nxge_lb_normal) {
148 				if (!statsp->mac_stats.link_up) {
149 					freemsg(mp);
150 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
151 					    "==> nxge_start: "
152 					    "link not up"));
153 					goto nxge_start_fail1;
154 				}
155 			}
156 			break;
157 		case PORT_10G_FIBER:
158 			/*
159 			 * For the following modes, check the link status
160 			 * before sending the packet out:
161 			 * nxge_lb_normal, nxge_lb_ext10g, nxge_lb_phy10g
162 			 */
163 			if (nxgep->statsp->port_stats.lb_mode <
164 			    nxge_lb_serdes10g) {
165 				if (!statsp->mac_stats.link_up) {
166 					freemsg(mp);
167 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
168 					    "==> nxge_start: "
169 					    "link not up"));
170 					goto nxge_start_fail1;
171 				}
172 			}
173 			break;
174 		}
175 	}
176 
177 	if ((!(nxgep->drv_state & STATE_HW_INITIALIZED)) ||
178 	    (nxgep->nxge_mac_state != NXGE_MAC_STARTED)) {
179 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
180 		    "==> nxge_start: hardware not initialized or stopped"));
181 		freemsg(mp);
182 		goto nxge_start_fail1;
183 	}
184 
185 	if (nxgep->soft_lso_enable) {
186 		mp_chain = nxge_lso_eliminate(mp);
187 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
188 		    "==> nxge_start(0): LSO mp $%p mp_chain $%p",
189 		    mp, mp_chain));
190 		if (mp_chain == NULL) {
191 			NXGE_ERROR_MSG((nxgep, TX_CTL,
192 			    "==> nxge_send(0): NULL mp_chain $%p != mp $%p",
193 			    mp_chain, mp));
194 			goto nxge_start_fail1;
195 		}
196 		if (mp_chain != mp) {
197 			NXGE_DEBUG_MSG((nxgep, TX_CTL,
198 			    "==> nxge_send(1): IS LSO mp_chain $%p != mp $%p",
199 			    mp_chain, mp));
200 			is_lso = B_TRUE;
201 			mp = mp_chain;
202 			mp_chain = mp_chain->b_next;
203 			mp->b_next = NULL;
204 		}
205 	}
206 
207 	hcksum_retrieve(mp, NULL, NULL, &start_offset,
208 	    &stuff_offset, &end_offset, &value, &cksum_flags);
209 	if (!NXGE_IS_VLAN_PACKET(mp->b_rptr)) {
210 		start_offset += sizeof (ether_header_t);
211 		stuff_offset += sizeof (ether_header_t);
212 	} else {
213 		start_offset += sizeof (struct ether_vlan_header);
214 		stuff_offset += sizeof (struct ether_vlan_header);
215 	}
216 
217 	if (cksum_flags & HCK_PARTIALCKSUM) {
218 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
219 		    "==> nxge_start: mp $%p len %d "
220 		    "cksum_flags 0x%x (partial checksum) ",
221 		    mp, MBLKL(mp), cksum_flags));
222 		cksum_on = B_TRUE;
223 	}
224 
225 	pkthdrp = (p_tx_pkt_hdr_all_t)&tmp_hdrp;
226 	pkthdrp->reserved = 0;
227 	tmp_hdrp.value = 0;
228 	nxge_fill_tx_hdr(mp, B_FALSE, cksum_on,
229 	    0, 0, pkthdrp,
230 	    start_offset, stuff_offset);
231 
232 	lso_again = B_FALSE;
233 	lso_ngathers = 0;
234 
235 	MUTEX_ENTER(&tx_ring_p->lock);
236 
237 	if (isLDOMservice(nxgep)) {
238 		tx_ring_p->tx_ring_busy = B_TRUE;
239 		if (tx_ring_p->tx_ring_offline) {
240 			freemsg(mp);
241 			tx_ring_p->tx_ring_busy = B_FALSE;
242 			(void) atomic_swap_32(&tx_ring_p->tx_ring_offline,
243 			    NXGE_TX_RING_OFFLINED);
244 			MUTEX_EXIT(&tx_ring_p->lock);
245 			return (status);
246 		}
247 	}
248 
249 	cur_index_lso = tx_ring_p->wr_index;
250 	lso_tail_wrap = tx_ring_p->wr_index_wrap;
251 start_again:
252 	ngathers = 0;
253 	sop_index = tx_ring_p->wr_index;
254 #ifdef	NXGE_DEBUG
255 	if (tx_ring_p->descs_pending) {
256 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
257 		    "desc pending %d ", tx_ring_p->descs_pending));
258 	}
259 
260 	dump_len = (int)(MBLKL(mp));
261 	dump_len = (dump_len > 128) ? 128: dump_len;
262 
263 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
264 	    "==> nxge_start: tdc %d: dumping ...: b_rptr $%p "
265 	    "(Before header reserve: ORIGINAL LEN %d)",
266 	    tx_ring_p->tdc,
267 	    mp->b_rptr,
268 	    dump_len));
269 
270 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: dump packets "
271 	    "(IP ORIGINAL b_rptr $%p): %s", mp->b_rptr,
272 	    nxge_dump_packet((char *)mp->b_rptr, dump_len)));
273 #endif
274 
275 	tdc_stats = tx_ring_p->tdc_stats;
276 	mark_mode = (tx_ring_p->descs_pending &&
277 	    ((tx_ring_p->tx_ring_size - tx_ring_p->descs_pending)
278 	    < nxge_tx_minfree));
279 
280 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
281 	    "TX Descriptor ring is channel %d mark mode %d",
282 	    tx_ring_p->tdc, mark_mode));
283 
284 	if ((tx_ring_p->descs_pending + lso_ngathers) >= nxge_reclaim_pending) {
285 		if (!nxge_txdma_reclaim(nxgep, tx_ring_p,
286 		    (nxge_tx_minfree + lso_ngathers))) {
287 			NXGE_DEBUG_MSG((nxgep, TX_CTL,
288 			    "TX Descriptor ring is full: channel %d",
289 			    tx_ring_p->tdc));
290 			NXGE_DEBUG_MSG((nxgep, TX_CTL,
291 			    "TX Descriptor ring is full: channel %d",
292 			    tx_ring_p->tdc));
293 			if (is_lso) {
294 				/*
295 				 * free the current mp and mp_chain if not FULL.
296 				 */
297 				tdc_stats->tx_no_desc++;
298 				NXGE_DEBUG_MSG((nxgep, TX_CTL,
299 				    "LSO packet: TX Descriptor ring is full: "
300 				    "channel %d",
301 				    tx_ring_p->tdc));
302 				goto nxge_start_fail_lso;
303 			} else {
304 				boolean_t skip_sched = B_FALSE;
305 
306 				cas32((uint32_t *)&tx_ring_p->queueing, 0, 1);
307 				tdc_stats->tx_no_desc++;
308 
309 				if (isLDOMservice(nxgep)) {
310 					tx_ring_p->tx_ring_busy = B_FALSE;
311 					if (tx_ring_p->tx_ring_offline) {
312 						(void) atomic_swap_32(
313 						    &tx_ring_p->tx_ring_offline,
314 						    NXGE_TX_RING_OFFLINED);
315 						skip_sched = B_TRUE;
316 					}
317 				}
318 
319 				MUTEX_EXIT(&tx_ring_p->lock);
320 				if (nxgep->resched_needed &&
321 				    !nxgep->resched_running && !skip_sched) {
322 					nxgep->resched_running = B_TRUE;
323 					ddi_trigger_softintr(nxgep->resched_id);
324 				}
325 				status = 1;
326 				goto nxge_start_fail1;
327 			}
328 		}
329 	}
330 
331 	nmp = mp;
332 	i = sop_index = tx_ring_p->wr_index;
333 	nmblks = 0;
334 	ngathers = 0;
335 	pkt_len = 0;
336 	pack_len = 0;
337 	clen = 0;
338 	last_bidx = -1;
339 	good_packet = B_TRUE;
340 
341 	desc_area = tx_ring_p->tdc_desc;
342 	npi_handle = desc_area.npi_handle;
343 	npi_desc_handle.regh = (nxge_os_acc_handle_t)
344 	    DMA_COMMON_ACC_HANDLE(desc_area);
345 	tx_desc_ring_vp = (p_tx_desc_t)DMA_COMMON_VPTR(desc_area);
346 	tx_desc_dma_handle = (nxge_os_dma_handle_t)
347 	    DMA_COMMON_HANDLE(desc_area);
348 	tx_msg_ring = tx_ring_p->tx_msg_ring;
349 
350 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: wr_index %d i %d",
351 	    sop_index, i));
352 
353 #ifdef	NXGE_DEBUG
354 	msgsize = msgdsize(nmp);
355 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
356 	    "==> nxge_start(1): wr_index %d i %d msgdsize %d",
357 	    sop_index, i, msgsize));
358 #endif
359 	/*
360 	 * The first 16 bytes of the premapped buffer are reserved
361 	 * for header. No padding will be used.
362 	 */
363 	pkt_len = pack_len = boff = TX_PKT_HEADER_SIZE;
364 	if (nxge_tx_use_bcopy && (nxgep->niu_type != N2_NIU)) {
365 		bcopy_thresh = (nxge_bcopy_thresh - TX_PKT_HEADER_SIZE);
366 	} else {
367 		bcopy_thresh = (TX_BCOPY_SIZE - TX_PKT_HEADER_SIZE);
368 	}
369 	while (nmp) {
370 		good_packet = B_TRUE;
371 		b_rptr = nmp->b_rptr;
372 		len = MBLKL(nmp);
373 		if (len <= 0) {
374 			nmp = nmp->b_cont;
375 			continue;
376 		}
377 		nmblks++;
378 
379 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(1): nmblks %d "
380 		    "len %d pkt_len %d pack_len %d",
381 		    nmblks, len, pkt_len, pack_len));
382 		/*
383 		 * Hardware limits the transfer length to 4K for NIU and
384 		 * 4076 (TX_MAX_TRANSFER_LENGTH) for Neptune. But we just
385 		 * use TX_MAX_TRANSFER_LENGTH as the limit for both.
386 		 * If len is longer than the limit, then we break nmp into
387 		 * two chunks: Make the first chunk equal to the limit and
388 		 * the second chunk for the remaining data. If the second
389 		 * chunk is still larger than the limit, then it will be
390 		 * broken into two in the next pass.
391 		 */
392 		if (len > TX_MAX_TRANSFER_LENGTH - TX_PKT_HEADER_SIZE) {
393 			if ((t_mp = dupb(nmp)) != NULL) {
394 				nmp->b_wptr = nmp->b_rptr +
395 				    (TX_MAX_TRANSFER_LENGTH
396 				    - TX_PKT_HEADER_SIZE);
397 				t_mp->b_rptr = nmp->b_wptr;
398 				t_mp->b_cont = nmp->b_cont;
399 				nmp->b_cont = t_mp;
400 				len = MBLKL(nmp);
401 			} else {
402 				if (is_lso) {
403 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
404 					    "LSO packet: dupb failed: "
405 					    "channel %d",
406 					    tx_ring_p->tdc));
407 					mp = nmp;
408 					goto nxge_start_fail_lso;
409 				} else {
410 					good_packet = B_FALSE;
411 					goto nxge_start_fail2;
412 				}
413 			}
414 		}
415 		tx_desc.value = 0;
416 		tx_desc_p = &tx_desc_ring_vp[i];
417 #ifdef	NXGE_DEBUG
418 		tx_desc_pp = &tx_desc_ring_pp[i];
419 #endif
420 		tx_msg_p = &tx_msg_ring[i];
421 #if defined(__i386)
422 		npi_desc_handle.regp = (uint32_t)tx_desc_p;
423 #else
424 		npi_desc_handle.regp = (uint64_t)tx_desc_p;
425 #endif
426 		if (!header_set &&
427 		    ((!nxge_tx_use_bcopy && (len > TX_BCOPY_SIZE)) ||
428 		    (len >= bcopy_thresh))) {
429 			header_set = B_TRUE;
430 			bcopy_thresh += TX_PKT_HEADER_SIZE;
431 			boff = 0;
432 			pack_len = 0;
433 			kaddr = (caddr_t)DMA_COMMON_VPTR(tx_msg_p->buf_dma);
434 			hdrp = (p_tx_pkt_header_t)kaddr;
435 			clen = pkt_len;
436 			dma_handle = tx_msg_p->buf_dma_handle;
437 			dma_ioaddr = DMA_COMMON_IOADDR(tx_msg_p->buf_dma);
438 			(void) ddi_dma_sync(dma_handle,
439 			    i * nxge_bcopy_thresh, nxge_bcopy_thresh,
440 			    DDI_DMA_SYNC_FORDEV);
441 
442 			tx_msg_p->flags.dma_type = USE_BCOPY;
443 			goto nxge_start_control_header_only;
444 		}
445 
446 		pkt_len += len;
447 		pack_len += len;
448 
449 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(3): "
450 		    "desc entry %d "
451 		    "DESC IOADDR $%p "
452 		    "desc_vp $%p tx_desc_p $%p "
453 		    "desc_pp $%p tx_desc_pp $%p "
454 		    "len %d pkt_len %d pack_len %d",
455 		    i,
456 		    DMA_COMMON_IOADDR(desc_area),
457 		    tx_desc_ring_vp, tx_desc_p,
458 		    tx_desc_ring_pp, tx_desc_pp,
459 		    len, pkt_len, pack_len));
460 
461 		if (len < bcopy_thresh) {
462 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(4): "
463 			    "USE BCOPY: "));
464 			if (nxge_tx_tiny_pack) {
465 				uint32_t blst =
466 				    TXDMA_DESC_NEXT_INDEX(i, -1,
467 				    tx_ring_p->tx_wrap_mask);
468 				NXGE_DEBUG_MSG((nxgep, TX_CTL,
469 				    "==> nxge_start(5): pack"));
470 				if ((pack_len <= bcopy_thresh) &&
471 				    (last_bidx == blst)) {
472 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
473 					    "==> nxge_start: pack(6) "
474 					    "(pkt_len %d pack_len %d)",
475 					    pkt_len, pack_len));
476 					i = blst;
477 					tx_desc_p = &tx_desc_ring_vp[i];
478 #ifdef	NXGE_DEBUG
479 					tx_desc_pp = &tx_desc_ring_pp[i];
480 #endif
481 					tx_msg_p = &tx_msg_ring[i];
482 					boff = pack_len - len;
483 					ngathers--;
484 				} else if (pack_len > bcopy_thresh &&
485 				    header_set) {
486 					pack_len = len;
487 					boff = 0;
488 					bcopy_thresh = nxge_bcopy_thresh;
489 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
490 					    "==> nxge_start(7): > max NEW "
491 					    "bcopy thresh %d "
492 					    "pkt_len %d pack_len %d(next)",
493 					    bcopy_thresh,
494 					    pkt_len, pack_len));
495 				}
496 				last_bidx = i;
497 			}
498 			kaddr = (caddr_t)DMA_COMMON_VPTR(tx_msg_p->buf_dma);
499 			if ((boff == TX_PKT_HEADER_SIZE) && (nmblks == 1)) {
500 				hdrp = (p_tx_pkt_header_t)kaddr;
501 				header_set = B_TRUE;
502 				NXGE_DEBUG_MSG((nxgep, TX_CTL,
503 				    "==> nxge_start(7_x2): "
504 				    "pkt_len %d pack_len %d (new hdrp $%p)",
505 				    pkt_len, pack_len, hdrp));
506 			}
507 			tx_msg_p->flags.dma_type = USE_BCOPY;
508 			kaddr += boff;
509 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(8): "
510 			    "USE BCOPY: before bcopy "
511 			    "DESC IOADDR $%p entry %d "
512 			    "bcopy packets %d "
513 			    "bcopy kaddr $%p "
514 			    "bcopy ioaddr (SAD) $%p "
515 			    "bcopy clen %d "
516 			    "bcopy boff %d",
517 			    DMA_COMMON_IOADDR(desc_area), i,
518 			    tdc_stats->tx_hdr_pkts,
519 			    kaddr,
520 			    dma_ioaddr,
521 			    clen,
522 			    boff));
523 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
524 			    "1USE BCOPY: "));
525 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
526 			    "2USE BCOPY: "));
527 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
528 			    "last USE BCOPY: copy from b_rptr $%p "
529 			    "to KADDR $%p (len %d offset %d",
530 			    b_rptr, kaddr, len, boff));
531 
532 			bcopy(b_rptr, kaddr, len);
533 
534 #ifdef	NXGE_DEBUG
535 			dump_len = (len > 128) ? 128: len;
536 			NXGE_DEBUG_MSG((nxgep, TX_CTL,
537 			    "==> nxge_start: dump packets "
538 			    "(After BCOPY len %d)"
539 			    "(b_rptr $%p): %s", len, nmp->b_rptr,
540 			    nxge_dump_packet((char *)nmp->b_rptr,
541 			    dump_len)));
542 #endif
543 
544 			dma_handle = tx_msg_p->buf_dma_handle;
545 			dma_ioaddr = DMA_COMMON_IOADDR(tx_msg_p->buf_dma);
546 			(void) ddi_dma_sync(dma_handle,
547 			    i * nxge_bcopy_thresh, nxge_bcopy_thresh,
548 			    DDI_DMA_SYNC_FORDEV);
549 			clen = len + boff;
550 			tdc_stats->tx_hdr_pkts++;
551 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(9): "
552 			    "USE BCOPY: "
553 			    "DESC IOADDR $%p entry %d "
554 			    "bcopy packets %d "
555 			    "bcopy kaddr $%p "
556 			    "bcopy ioaddr (SAD) $%p "
557 			    "bcopy clen %d "
558 			    "bcopy boff %d",
559 			    DMA_COMMON_IOADDR(desc_area),
560 			    i,
561 			    tdc_stats->tx_hdr_pkts,
562 			    kaddr,
563 			    dma_ioaddr,
564 			    clen,
565 			    boff));
566 		} else {
567 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(12): "
568 			    "USE DVMA: len %d", len));
569 			tx_msg_p->flags.dma_type = USE_DMA;
570 			dma_flags = DDI_DMA_WRITE;
571 			if (len < nxge_dma_stream_thresh) {
572 				dma_flags |= DDI_DMA_CONSISTENT;
573 			} else {
574 				dma_flags |= DDI_DMA_STREAMING;
575 			}
576 
577 			dma_handle = tx_msg_p->dma_handle;
578 			status = ddi_dma_addr_bind_handle(dma_handle, NULL,
579 			    (caddr_t)b_rptr, len, dma_flags,
580 			    DDI_DMA_DONTWAIT, NULL,
581 			    &dma_cookie, &ncookies);
582 			if (status == DDI_DMA_MAPPED) {
583 				dma_ioaddr = dma_cookie.dmac_laddress;
584 				len = (int)dma_cookie.dmac_size;
585 				clen = (uint32_t)dma_cookie.dmac_size;
586 				NXGE_DEBUG_MSG((nxgep, TX_CTL,
587 				    "==> nxge_start(12_1): "
588 				    "USE DVMA: len %d clen %d "
589 				    "ngathers %d",
590 				    len, clen,
591 				    ngathers));
592 #if defined(__i386)
593 				npi_desc_handle.regp = (uint32_t)tx_desc_p;
594 #else
595 				npi_desc_handle.regp = (uint64_t)tx_desc_p;
596 #endif
597 				while (ncookies > 1) {
598 					ngathers++;
599 					/*
600 					 * this is the fix for multiple
601 					 * cookies, which are basically
602 					 * a descriptor entry, we don't set
603 					 * SOP bit as well as related fields
604 					 */
605 
606 					(void) npi_txdma_desc_gather_set(
607 					    npi_desc_handle,
608 					    &tx_desc,
609 					    (ngathers -1),
610 					    mark_mode,
611 					    ngathers,
612 					    dma_ioaddr,
613 					    clen);
614 
615 					tx_msg_p->tx_msg_size = clen;
616 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
617 					    "==> nxge_start:  DMA "
618 					    "ncookie %d "
619 					    "ngathers %d "
620 					    "dma_ioaddr $%p len %d"
621 					    "desc $%p descp $%p (%d)",
622 					    ncookies,
623 					    ngathers,
624 					    dma_ioaddr, clen,
625 					    *tx_desc_p, tx_desc_p, i));
626 
627 					ddi_dma_nextcookie(dma_handle,
628 					    &dma_cookie);
629 					dma_ioaddr =
630 					    dma_cookie.dmac_laddress;
631 
632 					len = (int)dma_cookie.dmac_size;
633 					clen = (uint32_t)dma_cookie.dmac_size;
634 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
635 					    "==> nxge_start(12_2): "
636 					    "USE DVMA: len %d clen %d ",
637 					    len, clen));
638 
639 					i = TXDMA_DESC_NEXT_INDEX(i, 1,
640 					    tx_ring_p->tx_wrap_mask);
641 					tx_desc_p = &tx_desc_ring_vp[i];
642 
643 #if defined(__i386)
644 					npi_desc_handle.regp =
645 					    (uint32_t)tx_desc_p;
646 #else
647 					npi_desc_handle.regp =
648 					    (uint64_t)tx_desc_p;
649 #endif
650 					tx_msg_p = &tx_msg_ring[i];
651 					tx_msg_p->flags.dma_type = USE_NONE;
652 					tx_desc.value = 0;
653 
654 					ncookies--;
655 				}
656 				tdc_stats->tx_ddi_pkts++;
657 				NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start:"
658 				    "DMA: ddi packets %d",
659 				    tdc_stats->tx_ddi_pkts));
660 			} else {
661 				NXGE_ERROR_MSG((nxgep, NXGE_ERR_CTL,
662 				    "dma mapping failed for %d "
663 				    "bytes addr $%p flags %x (%d)",
664 				    len, b_rptr, status, status));
665 				good_packet = B_FALSE;
666 				tdc_stats->tx_dma_bind_fail++;
667 				tx_msg_p->flags.dma_type = USE_NONE;
668 				if (is_lso) {
669 					mp = nmp;
670 					goto nxge_start_fail_lso;
671 				} else {
672 					goto nxge_start_fail2;
673 				}
674 			}
675 		} /* ddi dvma */
676 
677 		if (is_lso) {
678 			nmp_lso_save = nmp;
679 		}
680 		nmp = nmp->b_cont;
681 nxge_start_control_header_only:
682 #if defined(__i386)
683 		npi_desc_handle.regp = (uint32_t)tx_desc_p;
684 #else
685 		npi_desc_handle.regp = (uint64_t)tx_desc_p;
686 #endif
687 		ngathers++;
688 
689 		if (ngathers == 1) {
690 #ifdef	NXGE_DEBUG
691 			save_desc_p = &sop_tx_desc;
692 #endif
693 			sop_tx_desc_p = &sop_tx_desc;
694 			sop_tx_desc_p->value = 0;
695 			sop_tx_desc_p->bits.hdw.tr_len = clen;
696 			sop_tx_desc_p->bits.hdw.sad = dma_ioaddr >> 32;
697 			sop_tx_desc_p->bits.ldw.sad = dma_ioaddr & 0xffffffff;
698 		} else {
699 #ifdef	NXGE_DEBUG
700 			save_desc_p = &tx_desc;
701 #endif
702 			tmp_desc_p = &tx_desc;
703 			tmp_desc_p->value = 0;
704 			tmp_desc_p->bits.hdw.tr_len = clen;
705 			tmp_desc_p->bits.hdw.sad = dma_ioaddr >> 32;
706 			tmp_desc_p->bits.ldw.sad = dma_ioaddr & 0xffffffff;
707 
708 			tx_desc_p->value = tmp_desc_p->value;
709 		}
710 
711 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(13): "
712 		    "Desc_entry %d ngathers %d "
713 		    "desc_vp $%p tx_desc_p $%p "
714 		    "len %d clen %d pkt_len %d pack_len %d nmblks %d "
715 		    "dma_ioaddr (SAD) $%p mark %d",
716 		    i, ngathers,
717 		    tx_desc_ring_vp, tx_desc_p,
718 		    len, clen, pkt_len, pack_len, nmblks,
719 		    dma_ioaddr, mark_mode));
720 
721 #ifdef NXGE_DEBUG
722 		npi_desc_handle.nxgep = nxgep;
723 		npi_desc_handle.function.function = nxgep->function_num;
724 		npi_desc_handle.function.instance = nxgep->instance;
725 		sad = (save_desc_p->value & TX_PKT_DESC_SAD_MASK);
726 		xfer_len = ((save_desc_p->value & TX_PKT_DESC_TR_LEN_MASK) >>
727 		    TX_PKT_DESC_TR_LEN_SHIFT);
728 
729 
730 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "\n\t: value 0x%llx\n"
731 		    "\t\tsad $%p\ttr_len %d len %d\tnptrs %d\t"
732 		    "mark %d sop %d\n",
733 		    save_desc_p->value,
734 		    sad,
735 		    save_desc_p->bits.hdw.tr_len,
736 		    xfer_len,
737 		    save_desc_p->bits.hdw.num_ptr,
738 		    save_desc_p->bits.hdw.mark,
739 		    save_desc_p->bits.hdw.sop));
740 
741 		npi_txdma_dump_desc_one(npi_desc_handle, NULL, i);
742 #endif
743 
744 		tx_msg_p->tx_msg_size = clen;
745 		i = TXDMA_DESC_NEXT_INDEX(i, 1, tx_ring_p->tx_wrap_mask);
746 		if (ngathers > nxge_tx_max_gathers) {
747 			good_packet = B_FALSE;
748 			hcksum_retrieve(mp, NULL, NULL, &start_offset,
749 			    &stuff_offset, &end_offset, &value,
750 			    &cksum_flags);
751 
752 			NXGE_DEBUG_MSG((NULL, TX_CTL,
753 			    "==> nxge_start(14): pull msg - "
754 			    "len %d pkt_len %d ngathers %d",
755 			    len, pkt_len, ngathers));
756 			/* Pull all message blocks from b_cont */
757 			if (is_lso) {
758 				mp = nmp_lso_save;
759 				goto nxge_start_fail_lso;
760 			}
761 			if ((msgpullup(mp, -1)) == NULL) {
762 				goto nxge_start_fail2;
763 			}
764 			goto nxge_start_fail2;
765 		}
766 	} /* while (nmp) */
767 
768 	tx_msg_p->tx_message = mp;
769 	tx_desc_p = &tx_desc_ring_vp[sop_index];
770 #if defined(__i386)
771 	npi_desc_handle.regp = (uint32_t)tx_desc_p;
772 #else
773 	npi_desc_handle.regp = (uint64_t)tx_desc_p;
774 #endif
775 
776 	pkthdrp = (p_tx_pkt_hdr_all_t)hdrp;
777 	pkthdrp->reserved = 0;
778 	hdrp->value = 0;
779 	bcopy(&tmp_hdrp, hdrp, sizeof (tx_pkt_header_t));
780 
781 	if (pkt_len > NXGE_MTU_DEFAULT_MAX) {
782 		tdc_stats->tx_jumbo_pkts++;
783 	}
784 
785 	min_len = (ETHERMIN + TX_PKT_HEADER_SIZE + (npads * 2));
786 	if (pkt_len < min_len) {
787 		/* Assume we use bcopy to premapped buffers */
788 		kaddr = (caddr_t)DMA_COMMON_VPTR(tx_msg_p->buf_dma);
789 		NXGE_DEBUG_MSG((NULL, TX_CTL,
790 		    "==> nxge_start(14-1): < (msg_min + 16)"
791 		    "len %d pkt_len %d min_len %d bzero %d ngathers %d",
792 		    len, pkt_len, min_len, (min_len - pkt_len), ngathers));
793 		bzero((kaddr + pkt_len), (min_len - pkt_len));
794 		pkt_len = tx_msg_p->tx_msg_size = min_len;
795 
796 		sop_tx_desc_p->bits.hdw.tr_len = min_len;
797 
798 		NXGE_MEM_PIO_WRITE64(npi_desc_handle, sop_tx_desc_p->value);
799 		tx_desc_p->value = sop_tx_desc_p->value;
800 
801 		NXGE_DEBUG_MSG((NULL, TX_CTL,
802 		    "==> nxge_start(14-2): < msg_min - "
803 		    "len %d pkt_len %d min_len %d ngathers %d",
804 		    len, pkt_len, min_len, ngathers));
805 	}
806 
807 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: cksum_flags 0x%x ",
808 	    cksum_flags));
809 	{
810 		uint64_t	tmp_len;
811 
812 		/* pkt_len already includes 16 + paddings!! */
813 		/* Update the control header length */
814 		tot_xfer_len = (pkt_len - TX_PKT_HEADER_SIZE);
815 		tmp_len = hdrp->value |
816 		    (tot_xfer_len << TX_PKT_HEADER_TOT_XFER_LEN_SHIFT);
817 
818 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
819 		    "==> nxge_start(15_x1): setting SOP "
820 		    "tot_xfer_len 0x%llx (%d) pkt_len %d tmp_len "
821 		    "0x%llx hdrp->value 0x%llx",
822 		    tot_xfer_len, tot_xfer_len, pkt_len,
823 		    tmp_len, hdrp->value));
824 #if defined(_BIG_ENDIAN)
825 		hdrp->value = ddi_swap64(tmp_len);
826 #else
827 		hdrp->value = tmp_len;
828 #endif
829 		NXGE_DEBUG_MSG((nxgep,
830 		    TX_CTL, "==> nxge_start(15_x2): setting SOP "
831 		    "after SWAP: tot_xfer_len 0x%llx pkt_len %d "
832 		    "tmp_len 0x%llx hdrp->value 0x%llx",
833 		    tot_xfer_len, pkt_len,
834 		    tmp_len, hdrp->value));
835 	}
836 
837 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(15): setting SOP "
838 	    "wr_index %d "
839 	    "tot_xfer_len (%d) pkt_len %d npads %d",
840 	    sop_index,
841 	    tot_xfer_len, pkt_len,
842 	    npads));
843 
844 	sop_tx_desc_p->bits.hdw.sop = 1;
845 	sop_tx_desc_p->bits.hdw.mark = mark_mode;
846 	sop_tx_desc_p->bits.hdw.num_ptr = ngathers;
847 
848 	NXGE_MEM_PIO_WRITE64(npi_desc_handle, sop_tx_desc_p->value);
849 
850 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(16): set SOP done"));
851 
852 #ifdef NXGE_DEBUG
853 	npi_desc_handle.nxgep = nxgep;
854 	npi_desc_handle.function.function = nxgep->function_num;
855 	npi_desc_handle.function.instance = nxgep->instance;
856 
857 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "\n\t: value 0x%llx\n"
858 	    "\t\tsad $%p\ttr_len %d len %d\tnptrs %d\tmark %d sop %d\n",
859 	    save_desc_p->value,
860 	    sad,
861 	    save_desc_p->bits.hdw.tr_len,
862 	    xfer_len,
863 	    save_desc_p->bits.hdw.num_ptr,
864 	    save_desc_p->bits.hdw.mark,
865 	    save_desc_p->bits.hdw.sop));
866 	(void) npi_txdma_dump_desc_one(npi_desc_handle, NULL, sop_index);
867 
868 	dump_len = (pkt_len > 128) ? 128: pkt_len;
869 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
870 	    "==> nxge_start: dump packets(17) (after sop set, len "
871 	    " (len/dump_len/pkt_len/tot_xfer_len) %d/%d/%d/%d):\n"
872 	    "ptr $%p: %s", len, dump_len, pkt_len, tot_xfer_len,
873 	    (char *)hdrp,
874 	    nxge_dump_packet((char *)hdrp, dump_len)));
875 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
876 	    "==> nxge_start(18): TX desc sync: sop_index %d",
877 	    sop_index));
878 #endif
879 
880 	if ((ngathers == 1) || tx_ring_p->wr_index < i) {
881 		(void) ddi_dma_sync(tx_desc_dma_handle,
882 		    sop_index * sizeof (tx_desc_t),
883 		    ngathers * sizeof (tx_desc_t),
884 		    DDI_DMA_SYNC_FORDEV);
885 
886 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "nxge_start(19): sync 1 "
887 		    "cs_off = 0x%02X cs_s_off = 0x%02X "
888 		    "pkt_len %d ngathers %d sop_index %d\n",
889 		    stuff_offset, start_offset,
890 		    pkt_len, ngathers, sop_index));
891 	} else { /* more than one descriptor and wrap around */
892 		uint32_t nsdescs = tx_ring_p->tx_ring_size - sop_index;
893 		(void) ddi_dma_sync(tx_desc_dma_handle,
894 		    sop_index * sizeof (tx_desc_t),
895 		    nsdescs * sizeof (tx_desc_t),
896 		    DDI_DMA_SYNC_FORDEV);
897 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "nxge_start(20): sync 1 "
898 		    "cs_off = 0x%02X cs_s_off = 0x%02X "
899 		    "pkt_len %d ngathers %d sop_index %d\n",
900 		    stuff_offset, start_offset,
901 		    pkt_len, ngathers, sop_index));
902 
903 		(void) ddi_dma_sync(tx_desc_dma_handle,
904 		    0,
905 		    (ngathers - nsdescs) * sizeof (tx_desc_t),
906 		    DDI_DMA_SYNC_FORDEV);
907 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "nxge_start(21): sync 2 "
908 		    "cs_off = 0x%02X cs_s_off = 0x%02X "
909 		    "pkt_len %d ngathers %d sop_index %d\n",
910 		    stuff_offset, start_offset,
911 		    pkt_len, ngathers, sop_index));
912 	}
913 
914 	tail_index = tx_ring_p->wr_index;
915 	tail_wrap = tx_ring_p->wr_index_wrap;
916 
917 	tx_ring_p->wr_index = i;
918 	if (tx_ring_p->wr_index <= tail_index) {
919 		tx_ring_p->wr_index_wrap = ((tail_wrap == B_TRUE) ?
920 		    B_FALSE : B_TRUE);
921 	}
922 
923 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: TX kick: "
924 	    "channel %d wr_index %d wrap %d ngathers %d desc_pend %d",
925 	    tx_ring_p->tdc,
926 	    tx_ring_p->wr_index,
927 	    tx_ring_p->wr_index_wrap,
928 	    ngathers,
929 	    tx_ring_p->descs_pending));
930 
931 	if (is_lso) {
932 		lso_ngathers += ngathers;
933 		if (mp_chain != NULL) {
934 			mp = mp_chain;
935 			mp_chain = mp_chain->b_next;
936 			mp->b_next = NULL;
937 			if (nxge_lso_kick_cnt == lso_ngathers) {
938 				tx_ring_p->descs_pending += lso_ngathers;
939 				{
940 					tx_ring_kick_t		kick;
941 
942 					kick.value = 0;
943 					kick.bits.ldw.wrap =
944 					    tx_ring_p->wr_index_wrap;
945 					kick.bits.ldw.tail =
946 					    (uint16_t)tx_ring_p->wr_index;
947 
948 					/* Kick the Transmit kick register */
949 					TXDMA_REG_WRITE64(
950 					    NXGE_DEV_NPI_HANDLE(nxgep),
951 					    TX_RING_KICK_REG,
952 					    (uint8_t)tx_ring_p->tdc,
953 					    kick.value);
954 					tdc_stats->tx_starts++;
955 
956 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
957 					    "==> nxge_start: more LSO: "
958 					    "LSO_CNT %d",
959 					    lso_ngathers));
960 				}
961 				lso_ngathers = 0;
962 				ngathers = 0;
963 				cur_index_lso = sop_index = tx_ring_p->wr_index;
964 				lso_tail_wrap = tx_ring_p->wr_index_wrap;
965 			}
966 			NXGE_DEBUG_MSG((nxgep, TX_CTL,
967 			    "==> nxge_start: lso again: "
968 			    "lso_gathers %d ngathers %d cur_index_lso %d "
969 			    "wr_index %d sop_index %d",
970 			    lso_ngathers, ngathers, cur_index_lso,
971 			    tx_ring_p->wr_index, sop_index));
972 
973 			NXGE_DEBUG_MSG((nxgep, TX_CTL,
974 			    "==> nxge_start: next : count %d",
975 			    lso_ngathers));
976 			lso_again = B_TRUE;
977 			goto start_again;
978 		}
979 		ngathers = lso_ngathers;
980 	}
981 
982 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: TX KICKING: "));
983 
984 	{
985 		tx_ring_kick_t		kick;
986 
987 		kick.value = 0;
988 		kick.bits.ldw.wrap = tx_ring_p->wr_index_wrap;
989 		kick.bits.ldw.tail = (uint16_t)tx_ring_p->wr_index;
990 
991 		/* Kick start the Transmit kick register */
992 		TXDMA_REG_WRITE64(NXGE_DEV_NPI_HANDLE(nxgep),
993 		    TX_RING_KICK_REG,
994 		    (uint8_t)tx_ring_p->tdc,
995 		    kick.value);
996 	}
997 
998 	tx_ring_p->descs_pending += ngathers;
999 	tdc_stats->tx_starts++;
1000 
1001 	if (isLDOMservice(nxgep)) {
1002 		tx_ring_p->tx_ring_busy = B_FALSE;
1003 		if (tx_ring_p->tx_ring_offline) {
1004 			(void) atomic_swap_32(&tx_ring_p->tx_ring_offline,
1005 			    NXGE_TX_RING_OFFLINED);
1006 		}
1007 	}
1008 
1009 	MUTEX_EXIT(&tx_ring_p->lock);
1010 
1011 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "<== nxge_start"));
1012 
1013 	return (status);
1014 
1015 nxge_start_fail_lso:
1016 	status = 0;
1017 	good_packet = B_FALSE;
1018 	if (mp != NULL) {
1019 		freemsg(mp);
1020 	}
1021 	if (mp_chain != NULL) {
1022 		freemsg(mp_chain);
1023 	}
1024 	if (!lso_again && !ngathers) {
1025 		if (isLDOMservice(nxgep)) {
1026 			tx_ring_p->tx_ring_busy = B_FALSE;
1027 			if (tx_ring_p->tx_ring_offline) {
1028 				(void) atomic_swap_32(
1029 				    &tx_ring_p->tx_ring_offline,
1030 				    NXGE_TX_RING_OFFLINED);
1031 			}
1032 		}
1033 
1034 		MUTEX_EXIT(&tx_ring_p->lock);
1035 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
1036 		    "==> nxge_start: lso exit (nothing changed)"));
1037 		goto nxge_start_fail1;
1038 	}
1039 
1040 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
1041 	    "==> nxge_start (channel %d): before lso "
1042 	    "lso_gathers %d ngathers %d cur_index_lso %d "
1043 	    "wr_index %d sop_index %d lso_again %d",
1044 	    tx_ring_p->tdc,
1045 	    lso_ngathers, ngathers, cur_index_lso,
1046 	    tx_ring_p->wr_index, sop_index, lso_again));
1047 
1048 	if (lso_again) {
1049 		lso_ngathers += ngathers;
1050 		ngathers = lso_ngathers;
1051 		sop_index = cur_index_lso;
1052 		tx_ring_p->wr_index = sop_index;
1053 		tx_ring_p->wr_index_wrap = lso_tail_wrap;
1054 	}
1055 
1056 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
1057 	    "==> nxge_start (channel %d): after lso "
1058 	    "lso_gathers %d ngathers %d cur_index_lso %d "
1059 	    "wr_index %d sop_index %d lso_again %d",
1060 	    tx_ring_p->tdc,
1061 	    lso_ngathers, ngathers, cur_index_lso,
1062 	    tx_ring_p->wr_index, sop_index, lso_again));
1063 
1064 nxge_start_fail2:
1065 	if (good_packet == B_FALSE) {
1066 		cur_index = sop_index;
1067 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: clean up"));
1068 		for (i = 0; i < ngathers; i++) {
1069 			tx_desc_p = &tx_desc_ring_vp[cur_index];
1070 #if defined(__i386)
1071 			npi_handle.regp = (uint32_t)tx_desc_p;
1072 #else
1073 			npi_handle.regp = (uint64_t)tx_desc_p;
1074 #endif
1075 			tx_msg_p = &tx_msg_ring[cur_index];
1076 			(void) npi_txdma_desc_set_zero(npi_handle, 1);
1077 			if (tx_msg_p->flags.dma_type == USE_DVMA) {
1078 				NXGE_DEBUG_MSG((nxgep, TX_CTL,
1079 				    "tx_desc_p = %X index = %d",
1080 				    tx_desc_p, tx_ring_p->rd_index));
1081 				(void) dvma_unload(tx_msg_p->dvma_handle,
1082 				    0, -1);
1083 				tx_msg_p->dvma_handle = NULL;
1084 				if (tx_ring_p->dvma_wr_index ==
1085 				    tx_ring_p->dvma_wrap_mask)
1086 					tx_ring_p->dvma_wr_index = 0;
1087 				else
1088 					tx_ring_p->dvma_wr_index++;
1089 				tx_ring_p->dvma_pending--;
1090 			} else if (tx_msg_p->flags.dma_type == USE_DMA) {
1091 				if (ddi_dma_unbind_handle(
1092 				    tx_msg_p->dma_handle)) {
1093 					cmn_err(CE_WARN, "!nxge_start: "
1094 					    "ddi_dma_unbind_handle failed");
1095 				}
1096 			}
1097 			tx_msg_p->flags.dma_type = USE_NONE;
1098 			cur_index = TXDMA_DESC_NEXT_INDEX(cur_index, 1,
1099 			    tx_ring_p->tx_wrap_mask);
1100 
1101 		}
1102 
1103 		nxgep->resched_needed = B_TRUE;
1104 	}
1105 
1106 	if (isLDOMservice(nxgep)) {
1107 		tx_ring_p->tx_ring_busy = B_FALSE;
1108 		if (tx_ring_p->tx_ring_offline) {
1109 			(void) atomic_swap_32(&tx_ring_p->tx_ring_offline,
1110 			    NXGE_TX_RING_OFFLINED);
1111 		}
1112 	}
1113 
1114 	MUTEX_EXIT(&tx_ring_p->lock);
1115 
1116 nxge_start_fail1:
1117 	/* Add FMA to check the access handle nxge_hregh */
1118 
1119 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "<== nxge_start"));
1120 
1121 	return (status);
1122 }
1123 
1124 int
1125 nxge_serial_tx(mblk_t *mp, void *arg)
1126 {
1127 	p_tx_ring_t		tx_ring_p = (p_tx_ring_t)arg;
1128 	p_nxge_t		nxgep = tx_ring_p->nxgep;
1129 	int			status = 0;
1130 
1131 	if (isLDOMservice(nxgep)) {
1132 		if (tx_ring_p->tx_ring_offline) {
1133 			freemsg(mp);
1134 			return (status);
1135 		}
1136 	}
1137 
1138 	status = nxge_start(nxgep, tx_ring_p, mp);
1139 	return (status);
1140 }
1141 
1142 boolean_t
1143 nxge_send(p_nxge_t nxgep, mblk_t *mp, p_mac_tx_hint_t hp)
1144 {
1145 	p_tx_ring_t 		*tx_rings;
1146 	uint8_t			ring_index;
1147 	p_tx_ring_t		tx_ring_p;
1148 	nxge_grp_t		*group;
1149 
1150 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_send"));
1151 
1152 	ASSERT(mp->b_next == NULL);
1153 
1154 	group = nxgep->tx_set.group[0];	/* The default group */
1155 	ring_index = nxge_tx_lb_ring_1(mp, group->count, hp);
1156 
1157 	tx_rings = nxgep->tx_rings->rings;
1158 	tx_ring_p = tx_rings[group->legend[ring_index]];
1159 
1160 	if (isLDOMservice(nxgep)) {
1161 		if (tx_ring_p->tx_ring_offline) {
1162 			/*
1163 			 * OFFLINE means that it is in the process of being
1164 			 * shared - that is, it has been claimed by the HIO
1165 			 * code, but hasn't been unlinked from <group> yet.
1166 			 * So in this case use the first TDC, which always
1167 			 * belongs to the service domain and can't be shared.
1168 			 */
1169 			ring_index = 0;
1170 			tx_ring_p = tx_rings[group->legend[ring_index]];
1171 		}
1172 	}
1173 
1174 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "count %d, tx_rings[%d] = %p",
1175 	    (int)group->count, group->legend[ring_index], tx_ring_p));
1176 
1177 	switch (nxge_tx_scheme) {
1178 	case NXGE_USE_START:
1179 		if (nxge_start(nxgep, tx_ring_p, mp)) {
1180 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "<== nxge_send: failed "
1181 			    "ring index %d", ring_index));
1182 			return (B_FALSE);
1183 		}
1184 		break;
1185 
1186 	case NXGE_USE_SERIAL:
1187 	default:
1188 		nxge_serialize_enter(tx_ring_p->serial, mp);
1189 		break;
1190 	}
1191 
1192 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "<== nxge_send: ring index %d",
1193 	    ring_index));
1194 
1195 	return (B_TRUE);
1196 }
1197 
1198 /*
1199  * nxge_m_tx() - send a chain of packets
1200  */
1201 mblk_t *
1202 nxge_m_tx(void *arg, mblk_t *mp)
1203 {
1204 	p_nxge_t 		nxgep = (p_nxge_t)arg;
1205 	mblk_t 			*next;
1206 	mac_tx_hint_t		hint;
1207 
1208 	NXGE_DEBUG_MSG((nxgep, DDI_CTL, "==> nxge_m_tx"));
1209 
1210 	if ((!(nxgep->drv_state & STATE_HW_INITIALIZED)) ||
1211 	    (nxgep->nxge_mac_state != NXGE_MAC_STARTED)) {
1212 		NXGE_DEBUG_MSG((nxgep, DDI_CTL,
1213 		    "==> nxge_m_tx: hardware not initialized"));
1214 		NXGE_DEBUG_MSG((nxgep, DDI_CTL,
1215 		    "<== nxge_m_tx"));
1216 		freemsgchain(mp);
1217 		mp = NULL;
1218 		return (mp);
1219 	}
1220 
1221 	hint.hash =  NULL;
1222 	hint.vid =  0;
1223 	hint.sap =  0;
1224 
1225 	while (mp != NULL) {
1226 		next = mp->b_next;
1227 		mp->b_next = NULL;
1228 
1229 		/*
1230 		 * Until Nemo tx resource works, the mac driver
1231 		 * does the load balancing based on TCP port,
1232 		 * or CPU. For debugging, we use a system
1233 		 * configurable parameter.
1234 		 */
1235 		if (!nxge_send(nxgep, mp, &hint)) {
1236 			mp->b_next = next;
1237 			break;
1238 		}
1239 
1240 		mp = next;
1241 
1242 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1243 		    "==> nxge_m_tx: (go back to loop) mp $%p next $%p",
1244 		    mp, next));
1245 	}
1246 
1247 	NXGE_DEBUG_MSG((nxgep, DDI_CTL, "<== nxge_m_tx"));
1248 	return (mp);
1249 }
1250 
1251 int
1252 nxge_tx_lb_ring_1(p_mblk_t mp, uint32_t maxtdcs, p_mac_tx_hint_t hp)
1253 {
1254 	uint8_t 		ring_index = 0;
1255 	uint8_t 		*tcp_port;
1256 	p_mblk_t 		nmp;
1257 	size_t 			mblk_len;
1258 	size_t 			iph_len;
1259 	size_t 			hdrs_size;
1260 	uint8_t			hdrs_buf[sizeof (struct  ether_header) +
1261 	    IP_MAX_HDR_LENGTH + sizeof (uint32_t)];
1262 				/*
1263 				 * allocate space big enough to cover
1264 				 * the max ip header length and the first
1265 				 * 4 bytes of the TCP/IP header.
1266 				 */
1267 
1268 	boolean_t		qos = B_FALSE;
1269 
1270 	NXGE_DEBUG_MSG((NULL, TX_CTL, "==> nxge_tx_lb_ring"));
1271 
1272 	if (hp->vid) {
1273 		qos = B_TRUE;
1274 	}
1275 	switch (nxge_tx_lb_policy) {
1276 	case NXGE_TX_LB_TCPUDP: /* default IPv4 TCP/UDP */
1277 	default:
1278 		tcp_port = mp->b_rptr;
1279 		if (!nxge_no_tx_lb && !qos &&
1280 		    (ntohs(((p_ether_header_t)tcp_port)->ether_type)
1281 		    == ETHERTYPE_IP)) {
1282 			nmp = mp;
1283 			mblk_len = MBLKL(nmp);
1284 			tcp_port = NULL;
1285 			if (mblk_len > sizeof (struct ether_header) +
1286 			    sizeof (uint8_t)) {
1287 				tcp_port = nmp->b_rptr +
1288 				    sizeof (struct ether_header);
1289 				mblk_len -= sizeof (struct ether_header);
1290 				iph_len = ((*tcp_port) & 0x0f) << 2;
1291 				if (mblk_len > (iph_len + sizeof (uint32_t))) {
1292 					tcp_port = nmp->b_rptr;
1293 				} else {
1294 					tcp_port = NULL;
1295 				}
1296 			}
1297 			if (tcp_port == NULL) {
1298 				hdrs_size = 0;
1299 				((p_ether_header_t)hdrs_buf)->ether_type = 0;
1300 				while ((nmp) && (hdrs_size <
1301 				    sizeof (hdrs_buf))) {
1302 					mblk_len = MBLKL(nmp);
1303 					if (mblk_len >=
1304 					    (sizeof (hdrs_buf) - hdrs_size))
1305 						mblk_len = sizeof (hdrs_buf) -
1306 						    hdrs_size;
1307 					bcopy(nmp->b_rptr,
1308 					    &hdrs_buf[hdrs_size], mblk_len);
1309 					hdrs_size += mblk_len;
1310 					nmp = nmp->b_cont;
1311 				}
1312 				tcp_port = hdrs_buf;
1313 			}
1314 			tcp_port += sizeof (ether_header_t);
1315 			if (!(tcp_port[6] & 0x3f) && !(tcp_port[7] & 0xff)) {
1316 				switch (tcp_port[9]) {
1317 				case IPPROTO_TCP:
1318 				case IPPROTO_UDP:
1319 				case IPPROTO_ESP:
1320 					tcp_port += ((*tcp_port) & 0x0f) << 2;
1321 					ring_index =
1322 					    ((tcp_port[0] ^
1323 					    tcp_port[1] ^
1324 					    tcp_port[2] ^
1325 					    tcp_port[3]) % maxtdcs);
1326 					break;
1327 
1328 				case IPPROTO_AH:
1329 					/* SPI starts at the 4th byte */
1330 					tcp_port += ((*tcp_port) & 0x0f) << 2;
1331 					ring_index =
1332 					    ((tcp_port[4] ^
1333 					    tcp_port[5] ^
1334 					    tcp_port[6] ^
1335 					    tcp_port[7]) % maxtdcs);
1336 					break;
1337 
1338 				default:
1339 					ring_index = tcp_port[19] % maxtdcs;
1340 					break;
1341 				}
1342 			} else { /* fragmented packet */
1343 				ring_index = tcp_port[19] % maxtdcs;
1344 			}
1345 		} else {
1346 			ring_index = mp->b_band % maxtdcs;
1347 		}
1348 		break;
1349 
1350 	case NXGE_TX_LB_HASH:
1351 		if (hp->hash) {
1352 #if defined(__i386)
1353 			ring_index = ((uint32_t)(hp->hash) % maxtdcs);
1354 #else
1355 			ring_index = ((uint64_t)(hp->hash) % maxtdcs);
1356 #endif
1357 		} else {
1358 			ring_index = mp->b_band % maxtdcs;
1359 		}
1360 		break;
1361 
1362 	case NXGE_TX_LB_DEST_MAC: /* Use destination MAC address */
1363 		tcp_port = mp->b_rptr;
1364 		ring_index = tcp_port[5] % maxtdcs;
1365 		break;
1366 	}
1367 
1368 	NXGE_DEBUG_MSG((NULL, TX_CTL, "<== nxge_tx_lb_ring"));
1369 
1370 	return (ring_index);
1371 }
1372 
1373 uint_t
1374 nxge_reschedule(caddr_t arg)
1375 {
1376 	p_nxge_t nxgep;
1377 
1378 	nxgep = (p_nxge_t)arg;
1379 
1380 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_reschedule"));
1381 
1382 	if (nxgep->nxge_mac_state == NXGE_MAC_STARTED &&
1383 	    nxgep->resched_needed) {
1384 		if (!isLDOMguest(nxgep))
1385 			mac_tx_update(nxgep->mach);
1386 #if defined(sun4v)
1387 		else {		/* isLDOMguest(nxgep) */
1388 			nxge_hio_data_t *nhd = (nxge_hio_data_t *)
1389 			    nxgep->nxge_hw_p->hio;
1390 			nx_vio_fp_t *vio = &nhd->hio.vio;
1391 
1392 			/* Call back vnet. */
1393 			if (vio->cb.vio_net_tx_update) {
1394 				(*vio->cb.vio_net_tx_update)
1395 				    (nxgep->hio_vr->vhp);
1396 			}
1397 		}
1398 #endif
1399 		nxgep->resched_needed = B_FALSE;
1400 		nxgep->resched_running = B_FALSE;
1401 	}
1402 
1403 	NXGE_DEBUG_MSG((NULL, TX_CTL, "<== nxge_reschedule"));
1404 	return (DDI_INTR_CLAIMED);
1405 }
1406 
1407 
1408 /* Software LSO starts here */
1409 static void
1410 nxge_hcksum_retrieve(mblk_t *mp,
1411     uint32_t *start, uint32_t *stuff, uint32_t *end,
1412     uint32_t *value, uint32_t *flags)
1413 {
1414 	if (mp->b_datap->db_type == M_DATA) {
1415 		if (flags != NULL) {
1416 			*flags = DB_CKSUMFLAGS(mp) & (HCK_IPV4_HDRCKSUM |
1417 			    HCK_PARTIALCKSUM | HCK_FULLCKSUM |
1418 			    HCK_FULLCKSUM_OK);
1419 			if ((*flags & (HCK_PARTIALCKSUM |
1420 			    HCK_FULLCKSUM)) != 0) {
1421 				if (value != NULL)
1422 					*value = (uint32_t)DB_CKSUM16(mp);
1423 				if ((*flags & HCK_PARTIALCKSUM) != 0) {
1424 					if (start != NULL)
1425 						*start =
1426 						    (uint32_t)DB_CKSUMSTART(mp);
1427 					if (stuff != NULL)
1428 						*stuff =
1429 						    (uint32_t)DB_CKSUMSTUFF(mp);
1430 					if (end != NULL)
1431 						*end =
1432 						    (uint32_t)DB_CKSUMEND(mp);
1433 				}
1434 			}
1435 		}
1436 	}
1437 }
1438 
1439 static void
1440 nxge_lso_info_get(mblk_t *mp, uint32_t *mss, uint32_t *flags)
1441 {
1442 	ASSERT(DB_TYPE(mp) == M_DATA);
1443 
1444 	*mss = 0;
1445 	if (flags != NULL) {
1446 		*flags = DB_CKSUMFLAGS(mp) & HW_LSO;
1447 		if ((*flags != 0) && (mss != NULL)) {
1448 			*mss = (uint32_t)DB_LSOMSS(mp);
1449 		}
1450 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1451 		    "==> nxge_lso_info_get(flag !=NULL): mss %d *flags 0x%x",
1452 		    *mss, *flags));
1453 	}
1454 
1455 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1456 	    "<== nxge_lso_info_get: mss %d", *mss));
1457 }
1458 
1459 /*
1460  * Do Soft LSO on the oversized packet.
1461  *
1462  * 1. Create a chain of message for headers.
1463  * 2. Fill up header messages with proper information.
1464  * 3. Copy Eithernet, IP, and TCP headers from the original message to
1465  *    each new message with necessary adjustments.
1466  *    * Unchange the ethernet header for DIX frames. (by default)
1467  *    * IP Total Length field is updated to MSS or less(only for the last one).
1468  *    * IP Identification value is incremented by one for each packet.
1469  *    * TCP sequence Number is recalculated according to the payload length.
1470  *    * Set FIN and/or PSH flags for the *last* packet if applied.
1471  *    * TCP partial Checksum
1472  * 4. Update LSO information in the first message header.
1473  * 5. Release the original message header.
1474  */
1475 static mblk_t *
1476 nxge_do_softlso(mblk_t *mp, uint32_t mss)
1477 {
1478 	uint32_t	hckflags;
1479 	int		pktlen;
1480 	int		hdrlen;
1481 	int		segnum;
1482 	int		i;
1483 	struct ether_vlan_header *evh;
1484 	int		ehlen, iphlen, tcphlen;
1485 	struct ip	*oiph, *niph;
1486 	struct tcphdr *otcph, *ntcph;
1487 	int		available, len, left;
1488 	uint16_t	ip_id;
1489 	uint32_t	tcp_seq;
1490 #ifdef __sparc
1491 	uint32_t	tcp_seq_tmp;
1492 #endif
1493 	mblk_t		*datamp;
1494 	uchar_t		*rptr;
1495 	mblk_t		*nmp;
1496 	mblk_t		*cmp;
1497 	mblk_t		*mp_chain;
1498 	boolean_t do_cleanup = B_FALSE;
1499 	t_uscalar_t start_offset = 0;
1500 	t_uscalar_t stuff_offset = 0;
1501 	t_uscalar_t value = 0;
1502 	uint16_t	l4_len;
1503 	ipaddr_t	src, dst;
1504 	uint32_t	cksum, sum, l4cksum;
1505 
1506 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1507 	    "==> nxge_do_softlso"));
1508 	/*
1509 	 * check the length of LSO packet payload and calculate the number of
1510 	 * segments to be generated.
1511 	 */
1512 	pktlen = msgsize(mp);
1513 	evh = (struct ether_vlan_header *)mp->b_rptr;
1514 
1515 	/* VLAN? */
1516 	if (evh->ether_tpid == htons(ETHERTYPE_VLAN))
1517 		ehlen = sizeof (struct ether_vlan_header);
1518 	else
1519 		ehlen = sizeof (struct ether_header);
1520 	oiph = (struct ip *)(mp->b_rptr + ehlen);
1521 	iphlen = oiph->ip_hl * 4;
1522 	otcph = (struct tcphdr *)(mp->b_rptr + ehlen + iphlen);
1523 	tcphlen = otcph->th_off * 4;
1524 
1525 	l4_len = pktlen - ehlen - iphlen;
1526 
1527 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1528 	    "==> nxge_do_softlso: mss %d oiph $%p "
1529 	    "original ip_sum oiph->ip_sum 0x%x "
1530 	    "original tcp_sum otcph->th_sum 0x%x "
1531 	    "oiph->ip_len %d pktlen %d ehlen %d "
1532 	    "l4_len %d (0x%x) ip_len - iphlen %d ",
1533 	    mss,
1534 	    oiph,
1535 	    oiph->ip_sum,
1536 	    otcph->th_sum,
1537 	    ntohs(oiph->ip_len), pktlen,
1538 	    ehlen,
1539 	    l4_len,
1540 	    l4_len,
1541 	    ntohs(oiph->ip_len) - iphlen));
1542 
1543 	/* IPv4 + TCP */
1544 	if (!(oiph->ip_v == IPV4_VERSION)) {
1545 		NXGE_ERROR_MSG((NULL, NXGE_ERR_CTL,
1546 		    "<== nxge_do_softlso: not IPV4 "
1547 		    "oiph->ip_len %d pktlen %d ehlen %d tcphlen %d",
1548 		    ntohs(oiph->ip_len), pktlen, ehlen,
1549 		    tcphlen));
1550 		freemsg(mp);
1551 		return (NULL);
1552 	}
1553 
1554 	if (!(oiph->ip_p == IPPROTO_TCP)) {
1555 		NXGE_ERROR_MSG((NULL, NXGE_ERR_CTL,
1556 		    "<== nxge_do_softlso: not TCP "
1557 		    "oiph->ip_len %d pktlen %d ehlen %d tcphlen %d",
1558 		    ntohs(oiph->ip_len), pktlen, ehlen,
1559 		    tcphlen));
1560 		freemsg(mp);
1561 		return (NULL);
1562 	}
1563 
1564 	if (!(ntohs(oiph->ip_len) == pktlen - ehlen)) {
1565 		NXGE_ERROR_MSG((NULL, NXGE_ERR_CTL,
1566 		    "<== nxge_do_softlso: len not matched  "
1567 		    "oiph->ip_len %d pktlen %d ehlen %d tcphlen %d",
1568 		    ntohs(oiph->ip_len), pktlen, ehlen,
1569 		    tcphlen));
1570 		freemsg(mp);
1571 		return (NULL);
1572 	}
1573 
1574 	otcph = (struct tcphdr *)(mp->b_rptr + ehlen + iphlen);
1575 	tcphlen = otcph->th_off * 4;
1576 
1577 	/* TCP flags can not include URG, RST, or SYN */
1578 	VERIFY((otcph->th_flags & (TH_SYN | TH_RST | TH_URG)) == 0);
1579 
1580 	hdrlen = ehlen + iphlen + tcphlen;
1581 
1582 	VERIFY(MBLKL(mp) >= hdrlen);
1583 
1584 	if (MBLKL(mp) > hdrlen) {
1585 		datamp = mp;
1586 		rptr = mp->b_rptr + hdrlen;
1587 	} else { /* = */
1588 		datamp = mp->b_cont;
1589 		rptr = datamp->b_rptr;
1590 	}
1591 
1592 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1593 	    "nxge_do_softlso: otcph $%p pktlen: %d, "
1594 	    "hdrlen %d ehlen %d iphlen %d tcphlen %d "
1595 	    "mblkl(mp): %d, mblkl(datamp): %d",
1596 	    otcph,
1597 	    pktlen, hdrlen, ehlen, iphlen, tcphlen,
1598 	    (int)MBLKL(mp), (int)MBLKL(datamp)));
1599 
1600 	hckflags = 0;
1601 	nxge_hcksum_retrieve(mp,
1602 	    &start_offset, &stuff_offset, &value, NULL, &hckflags);
1603 
1604 	dst = oiph->ip_dst.s_addr;
1605 	src = oiph->ip_src.s_addr;
1606 
1607 	cksum = (dst >> 16) + (dst & 0xFFFF) +
1608 	    (src >> 16) + (src & 0xFFFF);
1609 	l4cksum = cksum + IP_TCP_CSUM_COMP;
1610 
1611 	sum = l4_len + l4cksum;
1612 	sum = (sum & 0xFFFF) + (sum >> 16);
1613 
1614 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1615 	    "==> nxge_do_softlso: dst 0x%x src 0x%x sum 0x%x ~new 0x%x "
1616 	    "hckflags 0x%x start_offset %d stuff_offset %d "
1617 	    "value (original) 0x%x th_sum 0x%x "
1618 	    "pktlen %d l4_len %d (0x%x) "
1619 	    "MBLKL(mp): %d, MBLKL(datamp): %d dump header %s",
1620 	    dst, src,
1621 	    (sum & 0xffff), (~sum & 0xffff),
1622 	    hckflags, start_offset, stuff_offset,
1623 	    value, otcph->th_sum,
1624 	    pktlen,
1625 	    l4_len,
1626 	    l4_len,
1627 	    ntohs(oiph->ip_len) - (int)MBLKL(mp),
1628 	    (int)MBLKL(datamp),
1629 	    nxge_dump_packet((char *)evh, 12)));
1630 
1631 	/*
1632 	 * Start to process.
1633 	 */
1634 	available = pktlen - hdrlen;
1635 	segnum = (available - 1) / mss + 1;
1636 
1637 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1638 	    "==> nxge_do_softlso: pktlen %d "
1639 	    "MBLKL(mp): %d, MBLKL(datamp): %d "
1640 	    "available %d mss %d segnum %d",
1641 	    pktlen, (int)MBLKL(mp), (int)MBLKL(datamp),
1642 	    available,
1643 	    mss,
1644 	    segnum));
1645 
1646 	VERIFY(segnum >= 2);
1647 
1648 	/*
1649 	 * Try to pre-allocate all header messages
1650 	 */
1651 	mp_chain = NULL;
1652 	for (i = 0; i < segnum; i++) {
1653 		if ((nmp = allocb(hdrlen, 0)) == NULL) {
1654 			/* Clean up the mp_chain */
1655 			while (mp_chain != NULL) {
1656 				nmp = mp_chain;
1657 				mp_chain = mp_chain->b_next;
1658 				freemsg(nmp);
1659 			}
1660 			NXGE_DEBUG_MSG((NULL, TX_CTL,
1661 			    "<== nxge_do_softlso: "
1662 			    "Could not allocate enough messages for headers!"));
1663 			freemsg(mp);
1664 			return (NULL);
1665 		}
1666 		nmp->b_next = mp_chain;
1667 		mp_chain = nmp;
1668 
1669 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1670 		    "==> nxge_do_softlso: "
1671 		    "mp $%p nmp $%p mp_chain $%p mp_chain->b_next $%p",
1672 		    mp, nmp, mp_chain, mp_chain->b_next));
1673 	}
1674 
1675 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1676 	    "==> nxge_do_softlso: mp $%p nmp $%p mp_chain $%p",
1677 	    mp, nmp, mp_chain));
1678 
1679 	/*
1680 	 * Associate payload with new packets
1681 	 */
1682 	cmp = mp_chain;
1683 	left = available;
1684 	while (cmp != NULL) {
1685 		nmp = dupb(datamp);
1686 		if (nmp == NULL) {
1687 			do_cleanup = B_TRUE;
1688 			NXGE_DEBUG_MSG((NULL, TX_CTL,
1689 			    "==>nxge_do_softlso: "
1690 			    "Can not dupb(datamp), have to do clean up"));
1691 			goto cleanup_allocated_msgs;
1692 		}
1693 
1694 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1695 		    "==> nxge_do_softlso: (loop) before mp $%p cmp $%p "
1696 		    "dupb nmp $%p len %d left %d msd %d ",
1697 		    mp, cmp, nmp, len, left, mss));
1698 
1699 		cmp->b_cont = nmp;
1700 		nmp->b_rptr = rptr;
1701 		len = (left < mss) ? left : mss;
1702 		left -= len;
1703 
1704 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1705 		    "==> nxge_do_softlso: (loop) after mp $%p cmp $%p "
1706 		    "dupb nmp $%p len %d left %d mss %d ",
1707 		    mp, cmp, nmp, len, left, mss));
1708 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1709 		    "nxge_do_softlso: before available: %d, "
1710 		    "left: %d, len: %d, segnum: %d MBLK(nmp): %d",
1711 		    available, left, len, segnum, (int)MBLKL(nmp)));
1712 
1713 		len -= MBLKL(nmp);
1714 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1715 		    "nxge_do_softlso: after available: %d, "
1716 		    "left: %d, len: %d, segnum: %d MBLK(nmp): %d",
1717 		    available, left, len, segnum, (int)MBLKL(nmp)));
1718 
1719 		while (len > 0) {
1720 			mblk_t *mmp = NULL;
1721 
1722 			NXGE_DEBUG_MSG((NULL, TX_CTL,
1723 			    "nxge_do_softlso: (4) len > 0 available: %d, "
1724 			    "left: %d, len: %d, segnum: %d MBLK(nmp): %d",
1725 			    available, left, len, segnum, (int)MBLKL(nmp)));
1726 
1727 			if (datamp->b_cont != NULL) {
1728 				datamp = datamp->b_cont;
1729 				rptr = datamp->b_rptr;
1730 				mmp = dupb(datamp);
1731 				if (mmp == NULL) {
1732 					do_cleanup = B_TRUE;
1733 					NXGE_DEBUG_MSG((NULL, TX_CTL,
1734 					    "==> nxge_do_softlso: "
1735 					    "Can not dupb(datamp) (1), :"
1736 					    "have to do clean up"));
1737 					NXGE_DEBUG_MSG((NULL, TX_CTL,
1738 					    "==> nxge_do_softlso: "
1739 					    "available: %d, left: %d, "
1740 					    "len: %d, MBLKL(nmp): %d",
1741 					    available, left, len,
1742 					    (int)MBLKL(nmp)));
1743 					goto cleanup_allocated_msgs;
1744 				}
1745 			} else {
1746 				NXGE_ERROR_MSG((NULL, NXGE_ERR_CTL,
1747 				    "==> nxge_do_softlso: "
1748 				    "(1)available: %d, left: %d, "
1749 				    "len: %d, MBLKL(nmp): %d",
1750 				    available, left, len,
1751 				    (int)MBLKL(nmp)));
1752 				cmn_err(CE_PANIC,
1753 				    "==> nxge_do_softlso: "
1754 				    "Pointers must have been corrupted!\n"
1755 				    "datamp: $%p, nmp: $%p, rptr: $%p",
1756 				    (void *)datamp,
1757 				    (void *)nmp,
1758 				    (void *)rptr);
1759 			}
1760 			nmp->b_cont = mmp;
1761 			nmp = mmp;
1762 			len -= MBLKL(nmp);
1763 		}
1764 		if (len < 0) {
1765 			nmp->b_wptr += len;
1766 			rptr = nmp->b_wptr;
1767 			NXGE_DEBUG_MSG((NULL, TX_CTL,
1768 			    "(5) len < 0 (less than 0)"
1769 			    "available: %d, left: %d, len: %d, MBLKL(nmp): %d",
1770 			    available, left, len, (int)MBLKL(nmp)));
1771 
1772 		} else if (len == 0) {
1773 			if (datamp->b_cont != NULL) {
1774 				NXGE_DEBUG_MSG((NULL, TX_CTL,
1775 				    "(5) len == 0"
1776 				    "available: %d, left: %d, len: %d, "
1777 				    "MBLKL(nmp): %d",
1778 				    available, left, len, (int)MBLKL(nmp)));
1779 				datamp = datamp->b_cont;
1780 				rptr = datamp->b_rptr;
1781 			} else {
1782 				NXGE_DEBUG_MSG((NULL, TX_CTL,
1783 				    "(6)available b_cont == NULL : %d, "
1784 				    "left: %d, len: %d, MBLKL(nmp): %d",
1785 				    available, left, len, (int)MBLKL(nmp)));
1786 
1787 				VERIFY(cmp->b_next == NULL);
1788 				VERIFY(left == 0);
1789 				break; /* Done! */
1790 			}
1791 		}
1792 		cmp = cmp->b_next;
1793 
1794 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1795 		    "(7) do_softlso: "
1796 		    "next mp in mp_chain available len != 0 : %d, "
1797 		    "left: %d, len: %d, MBLKL(nmp): %d",
1798 		    available, left, len, (int)MBLKL(nmp)));
1799 	}
1800 
1801 	/*
1802 	 * From now, start to fill up all headers for the first message
1803 	 * Hardware checksum flags need to be updated separately for FULLCKSUM
1804 	 * and PARTIALCKSUM cases. For full checksum, copy the original flags
1805 	 * into every new packet is enough. But for HCK_PARTIALCKSUM, all
1806 	 * required fields need to be updated properly.
1807 	 */
1808 	nmp = mp_chain;
1809 	bcopy(mp->b_rptr, nmp->b_rptr, hdrlen);
1810 	nmp->b_wptr = nmp->b_rptr + hdrlen;
1811 	niph = (struct ip *)(nmp->b_rptr + ehlen);
1812 	niph->ip_len = htons(mss + iphlen + tcphlen);
1813 	ip_id = ntohs(niph->ip_id);
1814 	ntcph = (struct tcphdr *)(nmp->b_rptr + ehlen + iphlen);
1815 #ifdef __sparc
1816 	bcopy((char *)&ntcph->th_seq, &tcp_seq_tmp, 4);
1817 	tcp_seq = ntohl(tcp_seq_tmp);
1818 #else
1819 	tcp_seq = ntohl(ntcph->th_seq);
1820 #endif
1821 
1822 	ntcph->th_flags &= ~(TH_FIN | TH_PUSH | TH_RST);
1823 
1824 	DB_CKSUMFLAGS(nmp) = (uint16_t)hckflags;
1825 	DB_CKSUMSTART(nmp) = start_offset;
1826 	DB_CKSUMSTUFF(nmp) = stuff_offset;
1827 
1828 	/* calculate IP checksum and TCP pseudo header checksum */
1829 	niph->ip_sum = 0;
1830 	niph->ip_sum = (uint16_t)nxge_csgen((uint16_t *)niph, iphlen);
1831 
1832 	l4_len = mss + tcphlen;
1833 	sum = htons(l4_len) + l4cksum;
1834 	sum = (sum & 0xFFFF) + (sum >> 16);
1835 	ntcph->th_sum = (sum & 0xffff);
1836 
1837 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1838 	    "==> nxge_do_softlso: first mp $%p (mp_chain $%p) "
1839 	    "mss %d pktlen %d l4_len %d (0x%x) "
1840 	    "MBLKL(mp): %d, MBLKL(datamp): %d "
1841 	    "ip_sum 0x%x "
1842 	    "th_sum 0x%x sum 0x%x ) "
1843 	    "dump first ip->tcp %s",
1844 	    nmp, mp_chain,
1845 	    mss,
1846 	    pktlen,
1847 	    l4_len,
1848 	    l4_len,
1849 	    (int)MBLKL(mp), (int)MBLKL(datamp),
1850 	    niph->ip_sum,
1851 	    ntcph->th_sum,
1852 	    sum,
1853 	    nxge_dump_packet((char *)niph, 52)));
1854 
1855 	cmp = nmp;
1856 	while ((nmp = nmp->b_next)->b_next != NULL) {
1857 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1858 		    "==>nxge_do_softlso: middle l4_len %d ", l4_len));
1859 		bcopy(cmp->b_rptr, nmp->b_rptr, hdrlen);
1860 		nmp->b_wptr = nmp->b_rptr + hdrlen;
1861 		niph = (struct ip *)(nmp->b_rptr + ehlen);
1862 		niph->ip_id = htons(++ip_id);
1863 		niph->ip_len = htons(mss + iphlen + tcphlen);
1864 		ntcph = (struct tcphdr *)(nmp->b_rptr + ehlen + iphlen);
1865 		tcp_seq += mss;
1866 
1867 		ntcph->th_flags &= ~(TH_FIN | TH_PUSH | TH_RST | TH_URG);
1868 
1869 #ifdef __sparc
1870 		tcp_seq_tmp = htonl(tcp_seq);
1871 		bcopy(&tcp_seq_tmp, (char *)&ntcph->th_seq, 4);
1872 #else
1873 		ntcph->th_seq = htonl(tcp_seq);
1874 #endif
1875 		DB_CKSUMFLAGS(nmp) = (uint16_t)hckflags;
1876 		DB_CKSUMSTART(nmp) = start_offset;
1877 		DB_CKSUMSTUFF(nmp) = stuff_offset;
1878 
1879 		/* calculate IP checksum and TCP pseudo header checksum */
1880 		niph->ip_sum = 0;
1881 		niph->ip_sum = (uint16_t)nxge_csgen((uint16_t *)niph, iphlen);
1882 		ntcph->th_sum = (sum & 0xffff);
1883 
1884 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1885 		    "==> nxge_do_softlso: middle ip_sum 0x%x "
1886 		    "th_sum 0x%x "
1887 		    " mp $%p (mp_chain $%p) pktlen %d "
1888 		    "MBLKL(mp): %d, MBLKL(datamp): %d ",
1889 		    niph->ip_sum,
1890 		    ntcph->th_sum,
1891 		    nmp, mp_chain,
1892 		    pktlen, (int)MBLKL(mp), (int)MBLKL(datamp)));
1893 	}
1894 
1895 	/* Last segment */
1896 	/*
1897 	 * Set FIN and/or PSH flags if present only in the last packet.
1898 	 * The ip_len could be different from prior packets.
1899 	 */
1900 	bcopy(cmp->b_rptr, nmp->b_rptr, hdrlen);
1901 	nmp->b_wptr = nmp->b_rptr + hdrlen;
1902 	niph = (struct ip *)(nmp->b_rptr + ehlen);
1903 	niph->ip_id = htons(++ip_id);
1904 	niph->ip_len = htons(msgsize(nmp->b_cont) + iphlen + tcphlen);
1905 	ntcph = (struct tcphdr *)(nmp->b_rptr + ehlen + iphlen);
1906 	tcp_seq += mss;
1907 #ifdef __sparc
1908 	tcp_seq_tmp = htonl(tcp_seq);
1909 	bcopy(&tcp_seq_tmp, (char *)&ntcph->th_seq, 4);
1910 #else
1911 	ntcph->th_seq = htonl(tcp_seq);
1912 #endif
1913 	ntcph->th_flags = (otcph->th_flags & ~TH_URG);
1914 
1915 	DB_CKSUMFLAGS(nmp) = (uint16_t)hckflags;
1916 	DB_CKSUMSTART(nmp) = start_offset;
1917 	DB_CKSUMSTUFF(nmp) = stuff_offset;
1918 
1919 	/* calculate IP checksum and TCP pseudo header checksum */
1920 	niph->ip_sum = 0;
1921 	niph->ip_sum = (uint16_t)nxge_csgen((uint16_t *)niph, iphlen);
1922 
1923 	l4_len = ntohs(niph->ip_len) - iphlen;
1924 	sum = htons(l4_len) + l4cksum;
1925 	sum = (sum & 0xFFFF) + (sum >> 16);
1926 	ntcph->th_sum = (sum & 0xffff);
1927 
1928 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1929 	    "==> nxge_do_softlso: last next "
1930 	    "niph->ip_sum 0x%x "
1931 	    "ntcph->th_sum 0x%x sum 0x%x "
1932 	    "dump last ip->tcp %s "
1933 	    "cmp $%p mp $%p (mp_chain $%p) pktlen %d (0x%x) "
1934 	    "l4_len %d (0x%x) "
1935 	    "MBLKL(mp): %d, MBLKL(datamp): %d ",
1936 	    niph->ip_sum,
1937 	    ntcph->th_sum, sum,
1938 	    nxge_dump_packet((char *)niph, 52),
1939 	    cmp, nmp, mp_chain,
1940 	    pktlen, pktlen,
1941 	    l4_len,
1942 	    l4_len,
1943 	    (int)MBLKL(mp), (int)MBLKL(datamp)));
1944 
1945 cleanup_allocated_msgs:
1946 	if (do_cleanup) {
1947 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1948 		    "==> nxge_do_softlso: "
1949 		    "Failed allocating messages, "
1950 		    "have to clean up and fail!"));
1951 		while (mp_chain != NULL) {
1952 			nmp = mp_chain;
1953 			mp_chain = mp_chain->b_next;
1954 			freemsg(nmp);
1955 		}
1956 	}
1957 	/*
1958 	 * We're done here, so just free the original message and return the
1959 	 * new message chain, that could be NULL if failed, back to the caller.
1960 	 */
1961 	freemsg(mp);
1962 
1963 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1964 	    "<== nxge_do_softlso:mp_chain $%p", mp_chain));
1965 	return (mp_chain);
1966 }
1967 
1968 /*
1969  * Will be called before NIC driver do further operation on the message.
1970  * The input message may include LSO information, if so, go to softlso logic
1971  * to eliminate the oversized LSO packet for the incapable underlying h/w.
1972  * The return could be the same non-LSO message or a message chain for LSO case.
1973  *
1974  * The driver needs to call this function per packet and process the whole chain
1975  * if applied.
1976  */
1977 static mblk_t *
1978 nxge_lso_eliminate(mblk_t *mp)
1979 {
1980 	uint32_t lsoflags;
1981 	uint32_t mss;
1982 
1983 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1984 	    "==>nxge_lso_eliminate:"));
1985 	nxge_lso_info_get(mp, &mss, &lsoflags);
1986 
1987 	if (lsoflags & HW_LSO) {
1988 		mblk_t *nmp;
1989 
1990 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1991 		    "==>nxge_lso_eliminate:"
1992 		    "HW_LSO:mss %d mp $%p",
1993 		    mss, mp));
1994 		if ((nmp = nxge_do_softlso(mp, mss)) != NULL) {
1995 			NXGE_DEBUG_MSG((NULL, TX_CTL,
1996 			    "<== nxge_lso_eliminate: "
1997 			    "LSO: nmp not NULL nmp $%p mss %d mp $%p",
1998 			    nmp, mss, mp));
1999 			return (nmp);
2000 		} else {
2001 			NXGE_DEBUG_MSG((NULL, TX_CTL,
2002 			    "<== nxge_lso_eliminate_ "
2003 			    "LSO: failed nmp NULL nmp $%p mss %d mp $%p",
2004 			    nmp, mss, mp));
2005 			return (NULL);
2006 		}
2007 	}
2008 
2009 	NXGE_DEBUG_MSG((NULL, TX_CTL,
2010 	    "<== nxge_lso_eliminate"));
2011 	return (mp);
2012 }
2013 
2014 static uint32_t
2015 nxge_csgen(uint16_t *adr, int len)
2016 {
2017 	int		i, odd;
2018 	uint32_t	sum = 0;
2019 	uint32_t	c = 0;
2020 
2021 	odd = len % 2;
2022 	for (i = 0; i < (len / 2); i++) {
2023 		sum += (adr[i] & 0xffff);
2024 	}
2025 	if (odd) {
2026 		sum += adr[len / 2] & 0xff00;
2027 	}
2028 	while ((c = ((sum & 0xffff0000) >> 16)) != 0) {
2029 		sum &= 0xffff;
2030 		sum += c;
2031 	}
2032 	return (~sum & 0xffff);
2033 }
2034