xref: /titanic_41/usr/src/uts/common/io/nxge/nxge_send.c (revision a3c4695861e3f0a8d3706f77ccd53683cca48d67)
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 
30 /* Software LSO required header files */
31 #include <netinet/tcp.h>
32 #include <inet/ip_impl.h>
33 #include <inet/tcp.h>
34 
35 static mblk_t *nxge_lso_eliminate(mblk_t *);
36 static mblk_t *nxge_do_softlso(mblk_t *mp, uint32_t mss);
37 static void nxge_lso_info_get(mblk_t *, uint32_t *, uint32_t *);
38 static void nxge_hcksum_retrieve(mblk_t *,
39     uint32_t *, uint32_t *, uint32_t *,
40     uint32_t *, uint32_t *);
41 static uint32_t nxge_csgen(uint16_t *, int);
42 
43 extern uint32_t		nxge_reclaim_pending;
44 extern uint32_t 	nxge_bcopy_thresh;
45 extern uint32_t 	nxge_dvma_thresh;
46 extern uint32_t 	nxge_dma_stream_thresh;
47 extern uint32_t		nxge_tx_minfree;
48 extern uint32_t		nxge_tx_intr_thres;
49 extern uint32_t		nxge_tx_max_gathers;
50 extern uint32_t		nxge_tx_tiny_pack;
51 extern uint32_t		nxge_tx_use_bcopy;
52 extern uint32_t		nxge_tx_lb_policy;
53 extern uint32_t		nxge_no_tx_lb;
54 extern nxge_tx_mode_t	nxge_tx_scheme;
55 extern uint32_t		nxge_lso_enable;
56 uint32_t		nxge_lso_kick_cnt = 2;
57 
58 typedef struct _mac_tx_hint {
59 	uint16_t	sap;
60 	uint16_t	vid;
61 	void		*hash;
62 } mac_tx_hint_t, *p_mac_tx_hint_t;
63 
64 int nxge_tx_lb_ring_1(p_mblk_t, uint32_t, p_mac_tx_hint_t);
65 
66 int
67 nxge_start(p_nxge_t nxgep, p_tx_ring_t tx_ring_p, p_mblk_t mp)
68 {
69 	int 			status = 0;
70 	p_tx_desc_t 		tx_desc_ring_vp;
71 	npi_handle_t		npi_desc_handle;
72 	nxge_os_dma_handle_t 	tx_desc_dma_handle;
73 	p_tx_desc_t 		tx_desc_p;
74 	p_tx_msg_t 		tx_msg_ring;
75 	p_tx_msg_t 		tx_msg_p;
76 	tx_desc_t		tx_desc, *tmp_desc_p;
77 	tx_desc_t		sop_tx_desc, *sop_tx_desc_p;
78 	p_tx_pkt_header_t	hdrp;
79 	p_tx_pkt_hdr_all_t	pkthdrp;
80 	uint8_t			npads = 0;
81 	uint64_t 		dma_ioaddr;
82 	uint32_t		dma_flags;
83 	int			last_bidx;
84 	uint8_t 		*b_rptr;
85 	caddr_t 		kaddr;
86 	uint32_t		nmblks;
87 	uint32_t		ngathers;
88 	uint32_t		clen;
89 	int 			len;
90 	uint32_t		pkt_len, pack_len, min_len;
91 	uint32_t		bcopy_thresh;
92 	int 			i, cur_index, sop_index;
93 	uint16_t		tail_index;
94 	boolean_t		tail_wrap = B_FALSE;
95 	nxge_dma_common_t	desc_area;
96 	nxge_os_dma_handle_t 	dma_handle;
97 	ddi_dma_cookie_t 	dma_cookie;
98 	npi_handle_t		npi_handle;
99 	p_mblk_t 		nmp;
100 	p_mblk_t		t_mp;
101 	uint32_t 		ncookies;
102 	boolean_t 		good_packet;
103 	boolean_t 		mark_mode = B_FALSE;
104 	p_nxge_stats_t 		statsp;
105 	p_nxge_tx_ring_stats_t tdc_stats;
106 	t_uscalar_t 		start_offset = 0;
107 	t_uscalar_t 		stuff_offset = 0;
108 	t_uscalar_t 		end_offset = 0;
109 	t_uscalar_t 		value = 0;
110 	t_uscalar_t 		cksum_flags = 0;
111 	boolean_t		cksum_on = B_FALSE;
112 	uint32_t		boff = 0;
113 	uint64_t		tot_xfer_len = 0, tmp_len = 0;
114 	boolean_t		header_set = B_FALSE;
115 #ifdef NXGE_DEBUG
116 	p_tx_desc_t 		tx_desc_ring_pp;
117 	p_tx_desc_t 		tx_desc_pp;
118 	tx_desc_t		*save_desc_p;
119 	int			dump_len;
120 	int			sad_len;
121 	uint64_t		sad;
122 	int			xfer_len;
123 	uint32_t		msgsize;
124 #endif
125 	p_mblk_t 		mp_chain = NULL;
126 	boolean_t		is_lso = B_FALSE;
127 	boolean_t		lso_again;
128 	int			cur_index_lso;
129 	p_mblk_t 		nmp_lso_save;
130 	uint32_t		lso_ngathers;
131 	boolean_t		lso_tail_wrap = B_FALSE;
132 
133 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
134 		"==> nxge_start: tx dma channel %d", tx_ring_p->tdc));
135 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
136 		"==> nxge_start: Starting tdc %d desc pending %d",
137 		tx_ring_p->tdc, tx_ring_p->descs_pending));
138 
139 	statsp = nxgep->statsp;
140 
141 	if (nxgep->statsp->port_stats.lb_mode == nxge_lb_normal) {
142 		if (!statsp->mac_stats.link_up) {
143 			freemsg(mp);
144 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
145 				"link not up or LB mode"));
146 			goto nxge_start_fail1;
147 		}
148 	}
149 
150 	if (nxge_lso_enable) {
151 		mp_chain = nxge_lso_eliminate(mp);
152 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
153 		    "==> nxge_start(0): LSO mp $%p mp_chain $%p",
154 		    mp, mp_chain));
155 		if (mp_chain == NULL) {
156 			NXGE_ERROR_MSG((nxgep, TX_CTL,
157 			    "==> nxge_send(0): NULL mp_chain $%p != mp $%p",
158 			    mp_chain, mp));
159 			goto nxge_start_fail1;
160 		}
161 		if (mp_chain != mp) {
162 			NXGE_DEBUG_MSG((nxgep, TX_CTL,
163 			    "==> nxge_send(1): IS LSO mp_chain $%p != mp $%p",
164 			    mp_chain, mp));
165 			is_lso = B_TRUE;
166 			mp = mp_chain;
167 			mp_chain = mp_chain->b_next;
168 			mp->b_next = NULL;
169 		}
170 	}
171 
172 	hcksum_retrieve(mp, NULL, NULL, &start_offset,
173 		&stuff_offset, &end_offset, &value, &cksum_flags);
174 	if (!NXGE_IS_VLAN_PACKET(mp->b_rptr)) {
175 		start_offset += sizeof (ether_header_t);
176 		stuff_offset += sizeof (ether_header_t);
177 	} else {
178 		start_offset += sizeof (struct ether_vlan_header);
179 		stuff_offset += sizeof (struct ether_vlan_header);
180 	}
181 
182 	if (cksum_flags & HCK_PARTIALCKSUM) {
183 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
184 			"==> nxge_start: mp $%p len %d "
185 			"cksum_flags 0x%x (partial checksum) ",
186 			mp, MBLKL(mp), cksum_flags));
187 		cksum_on = B_TRUE;
188 	}
189 
190 	lso_again = B_FALSE;
191 	lso_ngathers = 0;
192 
193 	MUTEX_ENTER(&tx_ring_p->lock);
194 	cur_index_lso = tx_ring_p->wr_index;
195 	lso_tail_wrap = tx_ring_p->wr_index_wrap;
196 start_again:
197 	ngathers = 0;
198 	sop_index = tx_ring_p->wr_index;
199 #ifdef	NXGE_DEBUG
200 	if (tx_ring_p->descs_pending) {
201 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
202 			"desc pending %d ", tx_ring_p->descs_pending));
203 	}
204 
205 	dump_len = (int)(MBLKL(mp));
206 	dump_len = (dump_len > 128) ? 128: dump_len;
207 
208 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
209 		"==> nxge_start: tdc %d: dumping ...: b_rptr $%p "
210 		"(Before header reserve: ORIGINAL LEN %d)",
211 		tx_ring_p->tdc,
212 		mp->b_rptr,
213 		dump_len));
214 
215 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: dump packets "
216 		"(IP ORIGINAL b_rptr $%p): %s", mp->b_rptr,
217 		nxge_dump_packet((char *)mp->b_rptr, dump_len)));
218 #endif
219 
220 	tdc_stats = tx_ring_p->tdc_stats;
221 	mark_mode = (tx_ring_p->descs_pending &&
222 		((tx_ring_p->tx_ring_size - tx_ring_p->descs_pending)
223 		< nxge_tx_minfree));
224 
225 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
226 		"TX Descriptor ring is channel %d mark mode %d",
227 		tx_ring_p->tdc, mark_mode));
228 
229 	if (!nxge_txdma_reclaim(nxgep, tx_ring_p, nxge_tx_minfree)) {
230 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
231 			"TX Descriptor ring is full: channel %d",
232 			tx_ring_p->tdc));
233 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
234 			"TX Descriptor ring is full: channel %d",
235 			tx_ring_p->tdc));
236 		if (is_lso) {
237 			/* free the current mp and mp_chain if not FULL */
238 			tdc_stats->tx_no_desc++;
239 			NXGE_DEBUG_MSG((nxgep, TX_CTL,
240 			    "LSO packet: TX Descriptor ring is full: "
241 			    "channel %d",
242 			    tx_ring_p->tdc));
243 			goto nxge_start_fail_lso;
244 		} else {
245 			cas32((uint32_t *)&tx_ring_p->queueing, 0, 1);
246 			tdc_stats->tx_no_desc++;
247 			MUTEX_EXIT(&tx_ring_p->lock);
248 			if (nxgep->resched_needed && !nxgep->resched_running) {
249 				nxgep->resched_running = B_TRUE;
250 				ddi_trigger_softintr(nxgep->resched_id);
251 			}
252 			status = 1;
253 			goto nxge_start_fail1;
254 		}
255 	}
256 
257 	nmp = mp;
258 	i = sop_index = tx_ring_p->wr_index;
259 	nmblks = 0;
260 	ngathers = 0;
261 	pkt_len = 0;
262 	pack_len = 0;
263 	clen = 0;
264 	last_bidx = -1;
265 	good_packet = B_TRUE;
266 
267 	desc_area = tx_ring_p->tdc_desc;
268 	npi_handle = desc_area.npi_handle;
269 	npi_desc_handle.regh = (nxge_os_acc_handle_t)
270 			DMA_COMMON_ACC_HANDLE(desc_area);
271 	tx_desc_ring_vp = (p_tx_desc_t)DMA_COMMON_VPTR(desc_area);
272 #ifdef	NXGE_DEBUG
273 	tx_desc_ring_pp = (p_tx_desc_t)DMA_COMMON_IOADDR(desc_area);
274 #endif
275 	tx_desc_dma_handle = (nxge_os_dma_handle_t)
276 			DMA_COMMON_HANDLE(desc_area);
277 	tx_msg_ring = tx_ring_p->tx_msg_ring;
278 
279 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: wr_index %d i %d",
280 		sop_index, i));
281 
282 #ifdef	NXGE_DEBUG
283 	msgsize = msgdsize(nmp);
284 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
285 		"==> nxge_start(1): wr_index %d i %d msgdsize %d",
286 		sop_index, i, msgsize));
287 #endif
288 	/*
289 	 * The first 16 bytes of the premapped buffer are reserved
290 	 * for header. No padding will be used.
291 	 */
292 	pkt_len = pack_len = boff = TX_PKT_HEADER_SIZE;
293 	if (nxge_tx_use_bcopy && (nxgep->niu_type != N2_NIU)) {
294 		bcopy_thresh = (nxge_bcopy_thresh - TX_PKT_HEADER_SIZE);
295 	} else {
296 		bcopy_thresh = (TX_BCOPY_SIZE - TX_PKT_HEADER_SIZE);
297 	}
298 	while (nmp) {
299 		good_packet = B_TRUE;
300 		b_rptr = nmp->b_rptr;
301 		len = MBLKL(nmp);
302 		if (len <= 0) {
303 			nmp = nmp->b_cont;
304 			continue;
305 		}
306 		nmblks++;
307 
308 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(1): nmblks %d "
309 			"len %d pkt_len %d pack_len %d",
310 			nmblks, len, pkt_len, pack_len));
311 		/*
312 		 * Hardware limits the transfer length to 4K for NIU and
313 		 * 4076 (TX_MAX_TRANSFER_LENGTH) for Neptune. But we just
314 		 * use TX_MAX_TRANSFER_LENGTH as the limit for both.
315 		 * If len is longer than the limit, then we break nmp into
316 		 * two chunks: Make the first chunk equal to the limit and
317 		 * the second chunk for the remaining data. If the second
318 		 * chunk is still larger than the limit, then it will be
319 		 * broken into two in the next pass.
320 		 */
321 		if (len > TX_MAX_TRANSFER_LENGTH - TX_PKT_HEADER_SIZE) {
322 			if ((t_mp = dupb(nmp)) != NULL) {
323 				nmp->b_wptr = nmp->b_rptr +
324 				    (TX_MAX_TRANSFER_LENGTH
325 				    - TX_PKT_HEADER_SIZE);
326 				t_mp->b_rptr = nmp->b_wptr;
327 				t_mp->b_cont = nmp->b_cont;
328 				nmp->b_cont = t_mp;
329 				len = MBLKL(nmp);
330 			} else {
331 				if (is_lso) {
332 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
333 					    "LSO packet: dupb failed: "
334 					    "channel %d",
335 					    tx_ring_p->tdc));
336 					mp = nmp;
337 					goto nxge_start_fail_lso;
338 				} else {
339 					good_packet = B_FALSE;
340 					goto nxge_start_fail2;
341 				}
342 			}
343 		}
344 		tx_desc.value = 0;
345 		tx_desc_p = &tx_desc_ring_vp[i];
346 #ifdef	NXGE_DEBUG
347 		tx_desc_pp = &tx_desc_ring_pp[i];
348 #endif
349 		tx_msg_p = &tx_msg_ring[i];
350 #if defined(__i386)
351 		npi_desc_handle.regp = (uint32_t)tx_desc_p;
352 #else
353 		npi_desc_handle.regp = (uint64_t)tx_desc_p;
354 #endif
355 		if (!header_set &&
356 			((!nxge_tx_use_bcopy && (len > TX_BCOPY_SIZE)) ||
357 				(len >= bcopy_thresh))) {
358 			header_set = B_TRUE;
359 			bcopy_thresh += TX_PKT_HEADER_SIZE;
360 			boff = 0;
361 			pack_len = 0;
362 			kaddr = (caddr_t)DMA_COMMON_VPTR(tx_msg_p->buf_dma);
363 			hdrp = (p_tx_pkt_header_t)kaddr;
364 			clen = pkt_len;
365 			dma_handle = tx_msg_p->buf_dma_handle;
366 			dma_ioaddr = DMA_COMMON_IOADDR(tx_msg_p->buf_dma);
367 			(void) ddi_dma_sync(dma_handle,
368 				i * nxge_bcopy_thresh, nxge_bcopy_thresh,
369 				DDI_DMA_SYNC_FORDEV);
370 
371 			tx_msg_p->flags.dma_type = USE_BCOPY;
372 			goto nxge_start_control_header_only;
373 		}
374 
375 		pkt_len += len;
376 		pack_len += len;
377 
378 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(3): "
379 			"desc entry %d "
380 			"DESC IOADDR $%p "
381 			"desc_vp $%p tx_desc_p $%p "
382 			"desc_pp $%p tx_desc_pp $%p "
383 			"len %d pkt_len %d pack_len %d",
384 			i,
385 			DMA_COMMON_IOADDR(desc_area),
386 			tx_desc_ring_vp, tx_desc_p,
387 			tx_desc_ring_pp, tx_desc_pp,
388 			len, pkt_len, pack_len));
389 
390 		if (len < bcopy_thresh) {
391 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(4): "
392 				"USE BCOPY: "));
393 			if (nxge_tx_tiny_pack) {
394 				uint32_t blst =
395 					TXDMA_DESC_NEXT_INDEX(i, -1,
396 						tx_ring_p->tx_wrap_mask);
397 				NXGE_DEBUG_MSG((nxgep, TX_CTL,
398 					"==> nxge_start(5): pack"));
399 				if ((pack_len <= bcopy_thresh) &&
400 					(last_bidx == blst)) {
401 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
402 						"==> nxge_start: pack(6) "
403 						"(pkt_len %d pack_len %d)",
404 						pkt_len, pack_len));
405 					i = blst;
406 					tx_desc_p = &tx_desc_ring_vp[i];
407 #ifdef	NXGE_DEBUG
408 					tx_desc_pp = &tx_desc_ring_pp[i];
409 #endif
410 					tx_msg_p = &tx_msg_ring[i];
411 					boff = pack_len - len;
412 					ngathers--;
413 				} else if (pack_len > bcopy_thresh &&
414 					header_set) {
415 					pack_len = len;
416 					boff = 0;
417 					bcopy_thresh = nxge_bcopy_thresh;
418 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
419 						"==> nxge_start(7): > max NEW "
420 						"bcopy thresh %d "
421 						"pkt_len %d pack_len %d(next)",
422 						bcopy_thresh,
423 						pkt_len, pack_len));
424 				}
425 				last_bidx = i;
426 			}
427 			kaddr = (caddr_t)DMA_COMMON_VPTR(tx_msg_p->buf_dma);
428 			if ((boff == TX_PKT_HEADER_SIZE) && (nmblks == 1)) {
429 				hdrp = (p_tx_pkt_header_t)kaddr;
430 				header_set = B_TRUE;
431 				NXGE_DEBUG_MSG((nxgep, TX_CTL,
432 					"==> nxge_start(7_x2): "
433 					"pkt_len %d pack_len %d (new hdrp $%p)",
434 					pkt_len, pack_len, hdrp));
435 			}
436 			tx_msg_p->flags.dma_type = USE_BCOPY;
437 			kaddr += boff;
438 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(8): "
439 				"USE BCOPY: before bcopy "
440 				"DESC IOADDR $%p entry %d "
441 				"bcopy packets %d "
442 				"bcopy kaddr $%p "
443 				"bcopy ioaddr (SAD) $%p "
444 				"bcopy clen %d "
445 				"bcopy boff %d",
446 				DMA_COMMON_IOADDR(desc_area), i,
447 				tdc_stats->tx_hdr_pkts,
448 				kaddr,
449 				dma_ioaddr,
450 				clen,
451 				boff));
452 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
453 				"1USE BCOPY: "));
454 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
455 				"2USE BCOPY: "));
456 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
457 				"last USE BCOPY: copy from b_rptr $%p "
458 				"to KADDR $%p (len %d offset %d",
459 				b_rptr, kaddr, len, boff));
460 
461 			bcopy(b_rptr, kaddr, len);
462 
463 #ifdef	NXGE_DEBUG
464 			dump_len = (len > 128) ? 128: len;
465 			NXGE_DEBUG_MSG((nxgep, TX_CTL,
466 				"==> nxge_start: dump packets "
467 				"(After BCOPY len %d)"
468 				"(b_rptr $%p): %s", len, nmp->b_rptr,
469 				nxge_dump_packet((char *)nmp->b_rptr,
470 				dump_len)));
471 #endif
472 
473 			dma_handle = tx_msg_p->buf_dma_handle;
474 			dma_ioaddr = DMA_COMMON_IOADDR(tx_msg_p->buf_dma);
475 			(void) ddi_dma_sync(dma_handle,
476 				i * nxge_bcopy_thresh, nxge_bcopy_thresh,
477 					DDI_DMA_SYNC_FORDEV);
478 			clen = len + boff;
479 			tdc_stats->tx_hdr_pkts++;
480 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(9): "
481 				"USE BCOPY: "
482 				"DESC IOADDR $%p entry %d "
483 				"bcopy packets %d "
484 				"bcopy kaddr $%p "
485 				"bcopy ioaddr (SAD) $%p "
486 				"bcopy clen %d "
487 				"bcopy boff %d",
488 				DMA_COMMON_IOADDR(desc_area),
489 				i,
490 				tdc_stats->tx_hdr_pkts,
491 				kaddr,
492 				dma_ioaddr,
493 				clen,
494 				boff));
495 		} else {
496 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(12): "
497 				"USE DVMA: len %d", len));
498 			tx_msg_p->flags.dma_type = USE_DMA;
499 			dma_flags = DDI_DMA_WRITE;
500 			if (len < nxge_dma_stream_thresh) {
501 				dma_flags |= DDI_DMA_CONSISTENT;
502 			} else {
503 				dma_flags |= DDI_DMA_STREAMING;
504 			}
505 
506 			dma_handle = tx_msg_p->dma_handle;
507 			status = ddi_dma_addr_bind_handle(dma_handle, NULL,
508 				(caddr_t)b_rptr, len, dma_flags,
509 				DDI_DMA_DONTWAIT, NULL,
510 				&dma_cookie, &ncookies);
511 			if (status == DDI_DMA_MAPPED) {
512 				dma_ioaddr = dma_cookie.dmac_laddress;
513 				len = (int)dma_cookie.dmac_size;
514 				clen = (uint32_t)dma_cookie.dmac_size;
515 				NXGE_DEBUG_MSG((nxgep, TX_CTL,
516 					"==> nxge_start(12_1): "
517 					"USE DVMA: len %d clen %d "
518 					"ngathers %d",
519 					len, clen,
520 					ngathers));
521 #if defined(__i386)
522 				npi_desc_handle.regp = (uint32_t)tx_desc_p;
523 #else
524 				npi_desc_handle.regp = (uint64_t)tx_desc_p;
525 #endif
526 				while (ncookies > 1) {
527 					ngathers++;
528 					/*
529 					 * this is the fix for multiple
530 					 * cookies, which are basically
531 					 * a descriptor entry, we don't set
532 					 * SOP bit as well as related fields
533 					 */
534 
535 					(void) npi_txdma_desc_gather_set(
536 						npi_desc_handle,
537 						&tx_desc,
538 						(ngathers -1),
539 						mark_mode,
540 						ngathers,
541 						dma_ioaddr,
542 						clen);
543 
544 					tx_msg_p->tx_msg_size = clen;
545 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
546 						"==> nxge_start:  DMA "
547 						"ncookie %d "
548 						"ngathers %d "
549 						"dma_ioaddr $%p len %d"
550 						"desc $%p descp $%p (%d)",
551 						ncookies,
552 						ngathers,
553 						dma_ioaddr, clen,
554 						*tx_desc_p, tx_desc_p, i));
555 
556 					ddi_dma_nextcookie(dma_handle,
557 							&dma_cookie);
558 					dma_ioaddr =
559 						dma_cookie.dmac_laddress;
560 
561 					len = (int)dma_cookie.dmac_size;
562 					clen = (uint32_t)dma_cookie.dmac_size;
563 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
564 						"==> nxge_start(12_2): "
565 						"USE DVMA: len %d clen %d ",
566 						len, clen));
567 
568 					i = TXDMA_DESC_NEXT_INDEX(i, 1,
569 						tx_ring_p->tx_wrap_mask);
570 					tx_desc_p = &tx_desc_ring_vp[i];
571 
572 					npi_desc_handle.regp =
573 #if defined(__i386)
574 						(uint32_t)tx_desc_p;
575 #else
576 						(uint64_t)tx_desc_p;
577 #endif
578 					tx_msg_p = &tx_msg_ring[i];
579 					tx_msg_p->flags.dma_type = USE_NONE;
580 					tx_desc.value = 0;
581 
582 					ncookies--;
583 				}
584 				tdc_stats->tx_ddi_pkts++;
585 				NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start:"
586 					"DMA: ddi packets %d",
587 					tdc_stats->tx_ddi_pkts));
588 			} else {
589 				NXGE_ERROR_MSG((nxgep, NXGE_ERR_CTL,
590 				    "dma mapping failed for %d "
591 				    "bytes addr $%p flags %x (%d)",
592 				    len, b_rptr, status, status));
593 				good_packet = B_FALSE;
594 				tdc_stats->tx_dma_bind_fail++;
595 				tx_msg_p->flags.dma_type = USE_NONE;
596 				if (is_lso) {
597 					mp = nmp;
598 					goto nxge_start_fail_lso;
599 				} else {
600 					goto nxge_start_fail2;
601 				}
602 			}
603 		} /* ddi dvma */
604 
605 		if (is_lso) {
606 			nmp_lso_save = nmp;
607 		}
608 		nmp = nmp->b_cont;
609 nxge_start_control_header_only:
610 #if defined(__i386)
611 		npi_desc_handle.regp = (uint32_t)tx_desc_p;
612 #else
613 		npi_desc_handle.regp = (uint64_t)tx_desc_p;
614 #endif
615 		ngathers++;
616 
617 		if (ngathers == 1) {
618 #ifdef	NXGE_DEBUG
619 			save_desc_p = &sop_tx_desc;
620 #endif
621 			sop_tx_desc_p = &sop_tx_desc;
622 			sop_tx_desc_p->value = 0;
623 			sop_tx_desc_p->bits.hdw.tr_len = clen;
624 			sop_tx_desc_p->bits.hdw.sad = dma_ioaddr >> 32;
625 			sop_tx_desc_p->bits.ldw.sad = dma_ioaddr & 0xffffffff;
626 		} else {
627 #ifdef	NXGE_DEBUG
628 			save_desc_p = &tx_desc;
629 #endif
630 			tmp_desc_p = &tx_desc;
631 			tmp_desc_p->value = 0;
632 			tmp_desc_p->bits.hdw.tr_len = clen;
633 			tmp_desc_p->bits.hdw.sad = dma_ioaddr >> 32;
634 			tmp_desc_p->bits.ldw.sad = dma_ioaddr & 0xffffffff;
635 
636 			tx_desc_p->value = tmp_desc_p->value;
637 		}
638 
639 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(13): "
640 			"Desc_entry %d ngathers %d "
641 			"desc_vp $%p tx_desc_p $%p "
642 			"len %d clen %d pkt_len %d pack_len %d nmblks %d "
643 			"dma_ioaddr (SAD) $%p mark %d",
644 			i, ngathers,
645 			tx_desc_ring_vp, tx_desc_p,
646 			len, clen, pkt_len, pack_len, nmblks,
647 			dma_ioaddr, mark_mode));
648 
649 #ifdef NXGE_DEBUG
650 		npi_desc_handle.nxgep = nxgep;
651 		npi_desc_handle.function.function = nxgep->function_num;
652 		npi_desc_handle.function.instance = nxgep->instance;
653 		sad = (save_desc_p->value & TX_PKT_DESC_SAD_MASK);
654 		xfer_len = ((save_desc_p->value & TX_PKT_DESC_TR_LEN_MASK) >>
655 			TX_PKT_DESC_TR_LEN_SHIFT);
656 
657 
658 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "\n\t: value 0x%llx\n"
659 			"\t\tsad $%p\ttr_len %d len %d\tnptrs %d\t"
660 			"mark %d sop %d\n",
661 			save_desc_p->value,
662 			sad,
663 			save_desc_p->bits.hdw.tr_len,
664 			xfer_len,
665 			save_desc_p->bits.hdw.num_ptr,
666 			save_desc_p->bits.hdw.mark,
667 			save_desc_p->bits.hdw.sop));
668 
669 		npi_txdma_dump_desc_one(npi_desc_handle, NULL, i);
670 #endif
671 
672 		tx_msg_p->tx_msg_size = clen;
673 		i = TXDMA_DESC_NEXT_INDEX(i, 1, tx_ring_p->tx_wrap_mask);
674 		if (ngathers > nxge_tx_max_gathers) {
675 			good_packet = B_FALSE;
676 			hcksum_retrieve(mp, NULL, NULL, &start_offset,
677 				&stuff_offset, &end_offset, &value,
678 				&cksum_flags);
679 
680 			NXGE_DEBUG_MSG((NULL, TX_CTL,
681 				"==> nxge_start(14): pull msg - "
682 				"len %d pkt_len %d ngathers %d",
683 				len, pkt_len, ngathers));
684 			/* Pull all message blocks from b_cont */
685 			if (is_lso) {
686 				mp = nmp_lso_save;
687 				goto nxge_start_fail_lso;
688 			}
689 			if ((msgpullup(mp, -1)) == NULL) {
690 				goto nxge_start_fail2;
691 			}
692 			goto nxge_start_fail2;
693 		}
694 	} /* while (nmp) */
695 
696 	tx_msg_p->tx_message = mp;
697 	tx_desc_p = &tx_desc_ring_vp[sop_index];
698 #if defined(__i386)
699 	npi_desc_handle.regp = (uint32_t)tx_desc_p;
700 #else
701 	npi_desc_handle.regp = (uint64_t)tx_desc_p;
702 #endif
703 
704 	pkthdrp = (p_tx_pkt_hdr_all_t)hdrp;
705 	pkthdrp->reserved = 0;
706 	hdrp->value = 0;
707 	(void) nxge_fill_tx_hdr(mp, B_FALSE, cksum_on,
708 		(pkt_len - TX_PKT_HEADER_SIZE), npads, pkthdrp);
709 
710 	if (pkt_len > NXGE_MTU_DEFAULT_MAX) {
711 		tdc_stats->tx_jumbo_pkts++;
712 	}
713 
714 	min_len = (nxgep->msg_min + TX_PKT_HEADER_SIZE + (npads * 2));
715 	if (pkt_len < min_len) {
716 		/* Assume we use bcopy to premapped buffers */
717 		kaddr = (caddr_t)DMA_COMMON_VPTR(tx_msg_p->buf_dma);
718 		NXGE_DEBUG_MSG((NULL, TX_CTL,
719 			"==> nxge_start(14-1): < (msg_min + 16)"
720 			"len %d pkt_len %d min_len %d bzero %d ngathers %d",
721 			len, pkt_len, min_len, (min_len - pkt_len), ngathers));
722 		bzero((kaddr + pkt_len), (min_len - pkt_len));
723 		pkt_len = tx_msg_p->tx_msg_size = min_len;
724 
725 		sop_tx_desc_p->bits.hdw.tr_len = min_len;
726 
727 		NXGE_MEM_PIO_WRITE64(npi_desc_handle, sop_tx_desc_p->value);
728 		tx_desc_p->value = sop_tx_desc_p->value;
729 
730 		NXGE_DEBUG_MSG((NULL, TX_CTL,
731 			"==> nxge_start(14-2): < msg_min - "
732 			"len %d pkt_len %d min_len %d ngathers %d",
733 			len, pkt_len, min_len, ngathers));
734 	}
735 
736 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: cksum_flags 0x%x ",
737 		cksum_flags));
738 	if (cksum_flags & HCK_PARTIALCKSUM) {
739 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
740 			"==> nxge_start: cksum_flags 0x%x (partial checksum) ",
741 			cksum_flags));
742 		cksum_on = B_TRUE;
743 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
744 			"==> nxge_start: from IP cksum_flags 0x%x "
745 			"(partial checksum) "
746 			"start_offset %d stuff_offset %d",
747 			cksum_flags, start_offset, stuff_offset));
748 		tmp_len = (uint64_t)(start_offset >> 1);
749 		hdrp->value |= (tmp_len << TX_PKT_HEADER_L4START_SHIFT);
750 		tmp_len = (uint64_t)(stuff_offset >> 1);
751 		hdrp->value |= (tmp_len << TX_PKT_HEADER_L4STUFF_SHIFT);
752 
753 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
754 			"==> nxge_start: from IP cksum_flags 0x%x "
755 			"(partial checksum) "
756 			"after SHIFT start_offset %d stuff_offset %d",
757 			cksum_flags, start_offset, stuff_offset));
758 	}
759 	{
760 		uint64_t	tmp_len;
761 
762 		/* pkt_len already includes 16 + paddings!! */
763 		/* Update the control header length */
764 		tot_xfer_len = (pkt_len - TX_PKT_HEADER_SIZE);
765 		tmp_len = hdrp->value |
766 			(tot_xfer_len << TX_PKT_HEADER_TOT_XFER_LEN_SHIFT);
767 
768 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
769 			"==> nxge_start(15_x1): setting SOP "
770 			"tot_xfer_len 0x%llx (%d) pkt_len %d tmp_len "
771 			"0x%llx hdrp->value 0x%llx",
772 			tot_xfer_len, tot_xfer_len, pkt_len,
773 			tmp_len, hdrp->value));
774 #if defined(_BIG_ENDIAN)
775 		hdrp->value = ddi_swap64(tmp_len);
776 #else
777 		hdrp->value = tmp_len;
778 #endif
779 		NXGE_DEBUG_MSG((nxgep,
780 			TX_CTL, "==> nxge_start(15_x2): setting SOP "
781 			"after SWAP: tot_xfer_len 0x%llx pkt_len %d "
782 			"tmp_len 0x%llx hdrp->value 0x%llx",
783 			tot_xfer_len, pkt_len,
784 			tmp_len, hdrp->value));
785 	}
786 
787 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(15): setting SOP "
788 		"wr_index %d "
789 		"tot_xfer_len (%d) pkt_len %d npads %d",
790 		sop_index,
791 		tot_xfer_len, pkt_len,
792 		npads));
793 
794 	sop_tx_desc_p->bits.hdw.sop = 1;
795 	sop_tx_desc_p->bits.hdw.mark = mark_mode;
796 	sop_tx_desc_p->bits.hdw.num_ptr = ngathers;
797 
798 	NXGE_MEM_PIO_WRITE64(npi_desc_handle, sop_tx_desc_p->value);
799 
800 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(16): set SOP done"));
801 
802 #ifdef NXGE_DEBUG
803 	npi_desc_handle.nxgep = nxgep;
804 	npi_desc_handle.function.function = nxgep->function_num;
805 	npi_desc_handle.function.instance = nxgep->instance;
806 
807 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "\n\t: value 0x%llx\n"
808 		"\t\tsad $%p\ttr_len %d len %d\tnptrs %d\tmark %d sop %d\n",
809 		save_desc_p->value,
810 		sad,
811 		save_desc_p->bits.hdw.tr_len,
812 		xfer_len,
813 		save_desc_p->bits.hdw.num_ptr,
814 		save_desc_p->bits.hdw.mark,
815 		save_desc_p->bits.hdw.sop));
816 	(void) npi_txdma_dump_desc_one(npi_desc_handle, NULL, sop_index);
817 
818 	dump_len = (pkt_len > 128) ? 128: pkt_len;
819 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
820 		"==> nxge_start: dump packets(17) (after sop set, len "
821 		" (len/dump_len/pkt_len/tot_xfer_len) %d/%d/%d/%d):\n"
822 		"ptr $%p: %s", len, dump_len, pkt_len, tot_xfer_len,
823 		(char *)hdrp,
824 		nxge_dump_packet((char *)hdrp, dump_len)));
825 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
826 		"==> nxge_start(18): TX desc sync: sop_index %d",
827 			sop_index));
828 #endif
829 
830 	if ((ngathers == 1) || tx_ring_p->wr_index < i) {
831 		(void) ddi_dma_sync(tx_desc_dma_handle,
832 			sop_index * sizeof (tx_desc_t),
833 			ngathers * sizeof (tx_desc_t),
834 			DDI_DMA_SYNC_FORDEV);
835 
836 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "nxge_start(19): sync 1 "
837 			"cs_off = 0x%02X cs_s_off = 0x%02X "
838 			"pkt_len %d ngathers %d sop_index %d\n",
839 			stuff_offset, start_offset,
840 			pkt_len, ngathers, sop_index));
841 	} else { /* more than one descriptor and wrap around */
842 		uint32_t nsdescs = tx_ring_p->tx_ring_size - sop_index;
843 		(void) ddi_dma_sync(tx_desc_dma_handle,
844 			sop_index * sizeof (tx_desc_t),
845 			nsdescs * sizeof (tx_desc_t),
846 			DDI_DMA_SYNC_FORDEV);
847 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "nxge_start(20): sync 1 "
848 			"cs_off = 0x%02X cs_s_off = 0x%02X "
849 			"pkt_len %d ngathers %d sop_index %d\n",
850 			stuff_offset, start_offset,
851 				pkt_len, ngathers, sop_index));
852 
853 		(void) ddi_dma_sync(tx_desc_dma_handle,
854 			0,
855 			(ngathers - nsdescs) * sizeof (tx_desc_t),
856 			DDI_DMA_SYNC_FORDEV);
857 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "nxge_start(21): sync 2 "
858 			"cs_off = 0x%02X cs_s_off = 0x%02X "
859 			"pkt_len %d ngathers %d sop_index %d\n",
860 			stuff_offset, start_offset,
861 			pkt_len, ngathers, sop_index));
862 	}
863 
864 	tail_index = tx_ring_p->wr_index;
865 	tail_wrap = tx_ring_p->wr_index_wrap;
866 
867 	tx_ring_p->wr_index = i;
868 	if (tx_ring_p->wr_index <= tail_index) {
869 		tx_ring_p->wr_index_wrap = ((tail_wrap == B_TRUE) ?
870 						B_FALSE : B_TRUE);
871 	}
872 
873 	tx_ring_p->descs_pending += ngathers;
874 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: TX kick: "
875 		"channel %d wr_index %d wrap %d ngathers %d desc_pend %d",
876 		tx_ring_p->tdc,
877 		tx_ring_p->wr_index,
878 		tx_ring_p->wr_index_wrap,
879 		ngathers,
880 		tx_ring_p->descs_pending));
881 
882 	if (is_lso) {
883 		lso_ngathers += ngathers;
884 		if (mp_chain != NULL) {
885 			mp = mp_chain;
886 			mp_chain = mp_chain->b_next;
887 			mp->b_next = NULL;
888 			if (nxge_lso_kick_cnt == lso_ngathers) {
889 				{
890 					tx_ring_kick_t		kick;
891 
892 					kick.value = 0;
893 					kick.bits.ldw.wrap =
894 					    tx_ring_p->wr_index_wrap;
895 					kick.bits.ldw.tail =
896 					    (uint16_t)tx_ring_p->wr_index;
897 
898 					/* Kick the Transmit kick register */
899 					TXDMA_REG_WRITE64(
900 					    NXGE_DEV_NPI_HANDLE(nxgep),
901 					    TX_RING_KICK_REG,
902 					    (uint8_t)tx_ring_p->tdc,
903 					    kick.value);
904 					tdc_stats->tx_starts++;
905 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
906 					    "==> nxge_start: more LSO: "
907 					    "LSO_CNT %d",
908 					    lso_gathers));
909 				}
910 				lso_ngathers = 0;
911 				ngathers = 0;
912 				cur_index_lso = sop_index = tx_ring_p->wr_index;
913 				lso_tail_wrap = tx_ring_p->wr_index_wrap;
914 			}
915 			NXGE_DEBUG_MSG((nxgep, TX_CTL,
916 			    "==> nxge_start: lso again: "
917 			    "lso_gathers %d ngathers %d cur_index_lso %d "
918 			    "wr_index %d sop_index %d",
919 			    lso_ngathers, ngathers, cur_index_lso,
920 			    tx_ring_p->wr_index, sop_index));
921 
922 			NXGE_DEBUG_MSG((nxgep, TX_CTL,
923 			    "==> nxge_start: next : count %d",
924 			    lso_gathers));
925 			lso_again = B_TRUE;
926 			goto start_again;
927 		}
928 	}
929 
930 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: TX KICKING: "));
931 
932 	{
933 		tx_ring_kick_t		kick;
934 
935 		kick.value = 0;
936 		kick.bits.ldw.wrap = tx_ring_p->wr_index_wrap;
937 		kick.bits.ldw.tail = (uint16_t)tx_ring_p->wr_index;
938 
939 		/* Kick start the Transmit kick register */
940 		TXDMA_REG_WRITE64(NXGE_DEV_NPI_HANDLE(nxgep),
941 			TX_RING_KICK_REG,
942 			(uint8_t)tx_ring_p->tdc,
943 			kick.value);
944 	}
945 
946 	tdc_stats->tx_starts++;
947 
948 	MUTEX_EXIT(&tx_ring_p->lock);
949 
950 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "<== nxge_start"));
951 
952 	return (status);
953 
954 nxge_start_fail_lso:
955 	status = 0;
956 	good_packet = B_FALSE;
957 	if (mp != NULL) {
958 		freemsg(mp);
959 	}
960 	if (mp_chain != NULL) {
961 		freemsg(mp_chain);
962 	}
963 	if (!lso_again && !ngathers) {
964 		MUTEX_EXIT(&tx_ring_p->lock);
965 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
966 		    "==> nxge_start: lso exit (nothing changed)"));
967 		goto nxge_start_fail1;
968 	}
969 
970 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
971 	    "==> nxge_start (channel %d): before lso "
972 	    "lso_gathers %d ngathers %d cur_index_lso %d "
973 	    "wr_index %d sop_index %d lso_again %d",
974 	    tx_ring_p->tdc,
975 	    lso_ngathers, ngathers, cur_index_lso,
976 	    tx_ring_p->wr_index, sop_index, lso_again));
977 
978 	if (lso_again) {
979 		lso_ngathers += ngathers;
980 		ngathers = lso_ngathers;
981 		sop_index = cur_index_lso;
982 		tx_ring_p->wr_index = sop_index;
983 		tx_ring_p->wr_index_wrap = lso_tail_wrap;
984 	}
985 
986 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
987 	    "==> nxge_start (channel %d): after lso "
988 	    "lso_gathers %d ngathers %d cur_index_lso %d "
989 	    "wr_index %d sop_index %d lso_again %d",
990 	    tx_ring_p->tdc,
991 	    lso_ngathers, ngathers, cur_index_lso,
992 	    tx_ring_p->wr_index, sop_index, lso_again));
993 
994 nxge_start_fail2:
995 	if (good_packet == B_FALSE) {
996 		cur_index = sop_index;
997 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: clean up"));
998 		for (i = 0; i < ngathers; i++) {
999 			tx_desc_p = &tx_desc_ring_vp[cur_index];
1000 #if defined(__i386)
1001 			npi_handle.regp = (uint32_t)tx_desc_p;
1002 #else
1003 			npi_handle.regp = (uint64_t)tx_desc_p;
1004 #endif
1005 			tx_msg_p = &tx_msg_ring[cur_index];
1006 			(void) npi_txdma_desc_set_zero(npi_handle, 1);
1007 			if (tx_msg_p->flags.dma_type == USE_DVMA) {
1008 				NXGE_DEBUG_MSG((nxgep, TX_CTL,
1009 				    "tx_desc_p = %X index = %d",
1010 				    tx_desc_p, tx_ring_p->rd_index));
1011 				(void) dvma_unload(tx_msg_p->dvma_handle,
1012 				    0, -1);
1013 				tx_msg_p->dvma_handle = NULL;
1014 				if (tx_ring_p->dvma_wr_index ==
1015 				    tx_ring_p->dvma_wrap_mask)
1016 					tx_ring_p->dvma_wr_index = 0;
1017 				else
1018 					tx_ring_p->dvma_wr_index++;
1019 				tx_ring_p->dvma_pending--;
1020 			} else if (tx_msg_p->flags.dma_type == USE_DMA) {
1021 				if (ddi_dma_unbind_handle(
1022 				    tx_msg_p->dma_handle)) {
1023 					cmn_err(CE_WARN, "!nxge_start: "
1024 					    "ddi_dma_unbind_handle failed");
1025 				}
1026 			}
1027 			tx_msg_p->flags.dma_type = USE_NONE;
1028 			cur_index = TXDMA_DESC_NEXT_INDEX(cur_index, 1,
1029 				tx_ring_p->tx_wrap_mask);
1030 
1031 		}
1032 
1033 		nxgep->resched_needed = B_TRUE;
1034 	}
1035 
1036 	MUTEX_EXIT(&tx_ring_p->lock);
1037 
1038 nxge_start_fail1:
1039 	/* Add FMA to check the access handle nxge_hregh */
1040 
1041 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "<== nxge_start"));
1042 
1043 	return (status);
1044 }
1045 
1046 int
1047 nxge_serial_tx(mblk_t *mp, void *arg)
1048 {
1049 	p_tx_ring_t		tx_ring_p = (p_tx_ring_t)arg;
1050 	p_nxge_t		nxgep = tx_ring_p->nxgep;
1051 
1052 	return (nxge_start(nxgep, tx_ring_p, mp));
1053 }
1054 
1055 boolean_t
1056 nxge_send(p_nxge_t nxgep, mblk_t *mp, p_mac_tx_hint_t hp)
1057 {
1058 	p_tx_ring_t 		*tx_rings;
1059 	uint8_t			ring_index;
1060 	p_tx_ring_t		tx_ring_p;
1061 
1062 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_send"));
1063 
1064 	ASSERT(mp->b_next == NULL);
1065 
1066 	ring_index = nxge_tx_lb_ring_1(mp, nxgep->max_tdcs, hp);
1067 	tx_rings = nxgep->tx_rings->rings;
1068 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_tx_msg: tx_rings $%p",
1069 		tx_rings));
1070 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_tx_msg: max_tdcs %d "
1071 		"ring_index %d", nxgep->max_tdcs, ring_index));
1072 
1073 	switch (nxge_tx_scheme) {
1074 	case NXGE_USE_START:
1075 		if (nxge_start(nxgep, tx_rings[ring_index], mp)) {
1076 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "<== nxge_send: failed "
1077 				"ring index %d", ring_index));
1078 			return (B_FALSE);
1079 		}
1080 		break;
1081 
1082 	case NXGE_USE_SERIAL:
1083 	default:
1084 		tx_ring_p = tx_rings[ring_index];
1085 		nxge_serialize_enter(tx_ring_p->serial, mp);
1086 		break;
1087 	}
1088 
1089 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "<== nxge_send: ring index %d",
1090 		ring_index));
1091 
1092 	return (B_TRUE);
1093 }
1094 
1095 /*
1096  * nxge_m_tx() - send a chain of packets
1097  */
1098 mblk_t *
1099 nxge_m_tx(void *arg, mblk_t *mp)
1100 {
1101 	p_nxge_t 		nxgep = (p_nxge_t)arg;
1102 	mblk_t 			*next;
1103 	mac_tx_hint_t		hint;
1104 
1105 	if (!(nxgep->drv_state & STATE_HW_INITIALIZED)) {
1106 		NXGE_DEBUG_MSG((nxgep, DDI_CTL,
1107 			"==> nxge_m_tx: hardware not initialized"));
1108 		NXGE_DEBUG_MSG((nxgep, DDI_CTL,
1109 			"<== nxge_m_tx"));
1110 		return (mp);
1111 	}
1112 
1113 	hint.hash =  NULL;
1114 	hint.vid =  0;
1115 	hint.sap =  0;
1116 
1117 	while (mp != NULL) {
1118 		next = mp->b_next;
1119 		mp->b_next = NULL;
1120 
1121 		/*
1122 		 * Until Nemo tx resource works, the mac driver
1123 		 * does the load balancing based on TCP port,
1124 		 * or CPU. For debugging, we use a system
1125 		 * configurable parameter.
1126 		 */
1127 		if (!nxge_send(nxgep, mp, &hint)) {
1128 			mp->b_next = next;
1129 			break;
1130 		}
1131 
1132 		mp = next;
1133 
1134 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1135 		    "==> nxge_m_tx: (go back to loop) mp $%p next $%p",
1136 		    mp, next));
1137 	}
1138 
1139 	return (mp);
1140 }
1141 
1142 int
1143 nxge_tx_lb_ring_1(p_mblk_t mp, uint32_t maxtdcs, p_mac_tx_hint_t hp)
1144 {
1145 	uint8_t 		ring_index = 0;
1146 	uint8_t 		*tcp_port;
1147 	p_mblk_t 		nmp;
1148 	size_t 			mblk_len;
1149 	size_t 			iph_len;
1150 	size_t 			hdrs_size;
1151 	uint8_t			hdrs_buf[sizeof (struct  ether_header) +
1152 					IP_MAX_HDR_LENGTH + sizeof (uint32_t)];
1153 				/*
1154 				 * allocate space big enough to cover
1155 				 * the max ip header length and the first
1156 				 * 4 bytes of the TCP/IP header.
1157 				 */
1158 
1159 	boolean_t		qos = B_FALSE;
1160 
1161 	NXGE_DEBUG_MSG((NULL, TX_CTL, "==> nxge_tx_lb_ring"));
1162 
1163 	if (hp->vid) {
1164 		qos = B_TRUE;
1165 	}
1166 	switch (nxge_tx_lb_policy) {
1167 	case NXGE_TX_LB_TCPUDP: /* default IPv4 TCP/UDP */
1168 	default:
1169 		tcp_port = mp->b_rptr;
1170 		if (!nxge_no_tx_lb && !qos &&
1171 			(ntohs(((p_ether_header_t)tcp_port)->ether_type)
1172 				== ETHERTYPE_IP)) {
1173 			nmp = mp;
1174 			mblk_len = MBLKL(nmp);
1175 			tcp_port = NULL;
1176 			if (mblk_len > sizeof (struct ether_header) +
1177 					sizeof (uint8_t)) {
1178 				tcp_port = nmp->b_rptr +
1179 					sizeof (struct ether_header);
1180 				mblk_len -= sizeof (struct ether_header);
1181 				iph_len = ((*tcp_port) & 0x0f) << 2;
1182 				if (mblk_len > (iph_len + sizeof (uint32_t))) {
1183 					tcp_port = nmp->b_rptr;
1184 				} else {
1185 					tcp_port = NULL;
1186 				}
1187 			}
1188 			if (tcp_port == NULL) {
1189 				hdrs_size = 0;
1190 				((p_ether_header_t)hdrs_buf)->ether_type = 0;
1191 				while ((nmp) && (hdrs_size <
1192 						sizeof (hdrs_buf))) {
1193 					mblk_len = MBLKL(nmp);
1194 					if (mblk_len >=
1195 						(sizeof (hdrs_buf) - hdrs_size))
1196 						mblk_len = sizeof (hdrs_buf) -
1197 							hdrs_size;
1198 					bcopy(nmp->b_rptr,
1199 						&hdrs_buf[hdrs_size], mblk_len);
1200 					hdrs_size += mblk_len;
1201 					nmp = nmp->b_cont;
1202 				}
1203 				tcp_port = hdrs_buf;
1204 			}
1205 			tcp_port += sizeof (ether_header_t);
1206 			if (!(tcp_port[6] & 0x3f) && !(tcp_port[7] & 0xff)) {
1207 				switch (tcp_port[9]) {
1208 				case IPPROTO_TCP:
1209 				case IPPROTO_UDP:
1210 				case IPPROTO_ESP:
1211 					tcp_port += ((*tcp_port) & 0x0f) << 2;
1212 					ring_index =
1213 					    ((tcp_port[0] ^
1214 					    tcp_port[1] ^
1215 					    tcp_port[2] ^
1216 					    tcp_port[3]) % maxtdcs);
1217 					break;
1218 
1219 				case IPPROTO_AH:
1220 					/* SPI starts at the 4th byte */
1221 					tcp_port += ((*tcp_port) & 0x0f) << 2;
1222 					ring_index =
1223 					    ((tcp_port[4] ^
1224 					    tcp_port[5] ^
1225 					    tcp_port[6] ^
1226 					    tcp_port[7]) % maxtdcs);
1227 					break;
1228 
1229 				default:
1230 					ring_index = tcp_port[19] % maxtdcs;
1231 					break;
1232 				}
1233 			} else { /* fragmented packet */
1234 				ring_index = tcp_port[19] % maxtdcs;
1235 			}
1236 		} else {
1237 			ring_index = mp->b_band % maxtdcs;
1238 		}
1239 		break;
1240 
1241 	case NXGE_TX_LB_HASH:
1242 		if (hp->hash) {
1243 #if defined(__i386)
1244 			ring_index = ((uint32_t)(hp->hash) % maxtdcs);
1245 #else
1246 			ring_index = ((uint64_t)(hp->hash) % maxtdcs);
1247 #endif
1248 		} else {
1249 			ring_index = mp->b_band % maxtdcs;
1250 		}
1251 		break;
1252 
1253 	case NXGE_TX_LB_DEST_MAC: /* Use destination MAC address */
1254 		tcp_port = mp->b_rptr;
1255 		ring_index = tcp_port[5] % maxtdcs;
1256 		break;
1257 	}
1258 
1259 	NXGE_DEBUG_MSG((NULL, TX_CTL, "<== nxge_tx_lb_ring"));
1260 
1261 	return (ring_index);
1262 }
1263 
1264 uint_t
1265 nxge_reschedule(caddr_t arg)
1266 {
1267 	p_nxge_t nxgep;
1268 
1269 	nxgep = (p_nxge_t)arg;
1270 
1271 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_reschedule"));
1272 
1273 	if (nxgep->nxge_mac_state == NXGE_MAC_STARTED &&
1274 			nxgep->resched_needed) {
1275 		mac_tx_update(nxgep->mach);
1276 		nxgep->resched_needed = B_FALSE;
1277 		nxgep->resched_running = B_FALSE;
1278 	}
1279 
1280 	NXGE_DEBUG_MSG((NULL, TX_CTL, "<== nxge_reschedule"));
1281 	return (DDI_INTR_CLAIMED);
1282 }
1283 
1284 
1285 /* Software LSO starts here */
1286 static void
1287 nxge_hcksum_retrieve(mblk_t *mp,
1288     uint32_t *start, uint32_t *stuff, uint32_t *end,
1289     uint32_t *value, uint32_t *flags)
1290 {
1291 	if (mp->b_datap->db_type == M_DATA) {
1292 		if (flags != NULL) {
1293 			*flags = DB_CKSUMFLAGS(mp) & (HCK_IPV4_HDRCKSUM |
1294 			    HCK_PARTIALCKSUM | HCK_FULLCKSUM |
1295 			    HCK_FULLCKSUM_OK);
1296 			if ((*flags & (HCK_PARTIALCKSUM |
1297 			    HCK_FULLCKSUM)) != 0) {
1298 				if (value != NULL)
1299 					*value = (uint32_t)DB_CKSUM16(mp);
1300 				if ((*flags & HCK_PARTIALCKSUM) != 0) {
1301 					if (start != NULL)
1302 						*start =
1303 						    (uint32_t)DB_CKSUMSTART(mp);
1304 					if (stuff != NULL)
1305 						*stuff =
1306 						    (uint32_t)DB_CKSUMSTUFF(mp);
1307 					if (end != NULL)
1308 						*end =
1309 						    (uint32_t)DB_CKSUMEND(mp);
1310 				}
1311 			}
1312 		}
1313 	}
1314 }
1315 
1316 static void
1317 nxge_lso_info_get(mblk_t *mp, uint32_t *mss, uint32_t *flags)
1318 {
1319 	ASSERT(DB_TYPE(mp) == M_DATA);
1320 
1321 	*mss = 0;
1322 	if (flags != NULL) {
1323 		*flags = DB_CKSUMFLAGS(mp) & HW_LSO;
1324 		if ((*flags != 0) && (mss != NULL)) {
1325 			*mss = (uint32_t)DB_LSOMSS(mp);
1326 		}
1327 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1328 		    "==> nxge_lso_info_get(flag !=NULL): mss %d *flags 0x%x",
1329 		    *mss, *flags));
1330 	}
1331 
1332 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1333 	    "<== nxge_lso_info_get: mss %d", *mss));
1334 }
1335 
1336 /*
1337  * Do Soft LSO on the oversized packet.
1338  *
1339  * 1. Create a chain of message for headers.
1340  * 2. Fill up header messages with proper information.
1341  * 3. Copy Eithernet, IP, and TCP headers from the original message to
1342  *    each new message with necessary adjustments.
1343  *    * Unchange the ethernet header for DIX frames. (by default)
1344  *    * IP Total Length field is updated to MSS or less(only for the last one).
1345  *    * IP Identification value is incremented by one for each packet.
1346  *    * TCP sequence Number is recalculated according to the payload length.
1347  *    * Set FIN and/or PSH flags for the *last* packet if applied.
1348  *    * TCP partial Checksum
1349  * 4. Update LSO information in the first message header.
1350  * 5. Release the original message header.
1351  */
1352 static mblk_t *
1353 nxge_do_softlso(mblk_t *mp, uint32_t mss)
1354 {
1355 	uint32_t	hckflags;
1356 	int		pktlen;
1357 	int		hdrlen;
1358 	int		segnum;
1359 	int		i;
1360 	struct ether_vlan_header *evh;
1361 	int		ehlen, iphlen, tcphlen;
1362 	struct ip	*oiph, *niph;
1363 	struct tcphdr *otcph, *ntcph;
1364 	int		available, len, left;
1365 	uint16_t	ip_id;
1366 	uint32_t	tcp_seq;
1367 #ifdef __sparc
1368 	uint32_t	tcp_seq_tmp;
1369 #endif
1370 	mblk_t		*datamp;
1371 	uchar_t		*rptr;
1372 	mblk_t		*nmp;
1373 	mblk_t		*cmp;
1374 	mblk_t		*mp_chain;
1375 	boolean_t do_cleanup = B_FALSE;
1376 	t_uscalar_t start_offset = 0;
1377 	t_uscalar_t stuff_offset = 0;
1378 	t_uscalar_t value = 0;
1379 	uint16_t	l4_len;
1380 	ipaddr_t	src, dst;
1381 	uint32_t	cksum, sum, l4cksum;
1382 
1383 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1384 	    "==> nxge_do_softlso"));
1385 	/*
1386 	 * check the length of LSO packet payload and calculate the number of
1387 	 * segments to be generated.
1388 	 */
1389 	pktlen = msgsize(mp);
1390 	evh = (struct ether_vlan_header *)mp->b_rptr;
1391 
1392 	/* VLAN? */
1393 	if (evh->ether_tpid == htons(ETHERTYPE_VLAN))
1394 		ehlen = sizeof (struct ether_vlan_header);
1395 	else
1396 		ehlen = sizeof (struct ether_header);
1397 	oiph = (struct ip *)(mp->b_rptr + ehlen);
1398 	iphlen = oiph->ip_hl * 4;
1399 	otcph = (struct tcphdr *)(mp->b_rptr + ehlen + iphlen);
1400 	tcphlen = otcph->th_off * 4;
1401 
1402 	l4_len = pktlen - ehlen - iphlen;
1403 
1404 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1405 	    "==> nxge_do_softlso: mss %d oiph $%p "
1406 	    "original ip_sum oiph->ip_sum 0x%x "
1407 	    "original tcp_sum otcph->th_sum 0x%x "
1408 	    "oiph->ip_len %d pktlen %d ehlen %d "
1409 	    "l4_len %d (0x%x) ip_len - iphlen %d ",
1410 	    mss,
1411 	    oiph,
1412 	    oiph->ip_sum,
1413 	    otcph->th_sum,
1414 	    ntohs(oiph->ip_len), pktlen,
1415 	    ehlen,
1416 	    l4_len,
1417 	    l4_len,
1418 	    ntohs(oiph->ip_len) - iphlen));
1419 
1420 	/* IPv4 + TCP */
1421 	if (!(oiph->ip_v == IPV4_VERSION)) {
1422 		NXGE_ERROR_MSG((NULL, NXGE_ERR_CTL,
1423 		    "<== nxge_do_softlso: not IPV4 "
1424 		    "oiph->ip_len %d pktlen %d ehlen %d tcphlen %d",
1425 		    ntohs(oiph->ip_len), pktlen, ehlen,
1426 		    tcphlen));
1427 		freemsg(mp);
1428 		return (NULL);
1429 	}
1430 
1431 	if (!(oiph->ip_p == IPPROTO_TCP)) {
1432 		NXGE_ERROR_MSG((NULL, NXGE_ERR_CTL,
1433 		    "<== nxge_do_softlso: not TCP "
1434 		    "oiph->ip_len %d pktlen %d ehlen %d tcphlen %d",
1435 		    ntohs(oiph->ip_len), pktlen, ehlen,
1436 		    tcphlen));
1437 		freemsg(mp);
1438 		return (NULL);
1439 	}
1440 
1441 	if (!(ntohs(oiph->ip_len) == pktlen - ehlen)) {
1442 		NXGE_ERROR_MSG((NULL, NXGE_ERR_CTL,
1443 		    "<== nxge_do_softlso: len not matched  "
1444 		    "oiph->ip_len %d pktlen %d ehlen %d tcphlen %d",
1445 		    ntohs(oiph->ip_len), pktlen, ehlen,
1446 		    tcphlen));
1447 		freemsg(mp);
1448 		return (NULL);
1449 	}
1450 
1451 	otcph = (struct tcphdr *)(mp->b_rptr + ehlen + iphlen);
1452 	tcphlen = otcph->th_off * 4;
1453 
1454 	/* TCP flags can not include URG, RST, or SYN */
1455 	VERIFY((otcph->th_flags & (TH_SYN | TH_RST | TH_URG)) == 0);
1456 
1457 	hdrlen = ehlen + iphlen + tcphlen;
1458 
1459 	VERIFY(MBLKL(mp) >= hdrlen);
1460 
1461 	if (MBLKL(mp) > hdrlen) {
1462 		datamp = mp;
1463 		rptr = mp->b_rptr + hdrlen;
1464 	} else { /* = */
1465 		datamp = mp->b_cont;
1466 		rptr = datamp->b_rptr;
1467 	}
1468 
1469 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1470 	    "nxge_do_softlso: otcph $%p pktlen: %d, "
1471 	    "hdrlen %d ehlen %d iphlen %d tcphlen %d "
1472 	    "mblkl(mp): %d, mblkl(datamp): %d",
1473 	    otcph,
1474 	    pktlen, hdrlen, ehlen, iphlen, tcphlen,
1475 	    (int)MBLKL(mp), (int)MBLKL(datamp)));
1476 
1477 	hckflags = 0;
1478 	nxge_hcksum_retrieve(mp,
1479 	    &start_offset, &stuff_offset, &value, NULL, &hckflags);
1480 
1481 	dst = oiph->ip_dst.s_addr;
1482 	src = oiph->ip_src.s_addr;
1483 
1484 	cksum = (dst >> 16) + (dst & 0xFFFF) +
1485 	    (src >> 16) + (src & 0xFFFF);
1486 	l4cksum = cksum + IP_TCP_CSUM_COMP;
1487 
1488 	sum = l4_len + l4cksum;
1489 	sum = (sum & 0xFFFF) + (sum >> 16);
1490 
1491 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1492 	    "==> nxge_do_softlso: dst 0x%x src 0x%x sum 0x%x ~new 0x%x "
1493 	    "hckflags 0x%x start_offset %d stuff_offset %d "
1494 	    "value (original) 0x%x th_sum 0x%x "
1495 	    "pktlen %d l4_len %d (0x%x) "
1496 	    "MBLKL(mp): %d, MBLKL(datamp): %d dump header %s",
1497 	    dst, src,
1498 	    (sum & 0xffff), (~sum & 0xffff),
1499 	    hckflags, start_offset, stuff_offset,
1500 	    value, otcph->th_sum,
1501 	    pktlen,
1502 	    l4_len,
1503 	    l4_len,
1504 	    ntohs(oiph->ip_len) - (int)MBLKL(mp),
1505 	    (int)MBLKL(datamp),
1506 	    nxge_dump_packet((char *)evh, 12)));
1507 
1508 	/*
1509 	 * Start to process.
1510 	 */
1511 	available = pktlen - hdrlen;
1512 	segnum = (available - 1) / mss + 1;
1513 
1514 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1515 	    "==> nxge_do_softlso: pktlen %d "
1516 	    "MBLKL(mp): %d, MBLKL(datamp): %d "
1517 	    "available %d mss %d segnum %d",
1518 	    pktlen, (int)MBLKL(mp), (int)MBLKL(datamp),
1519 	    available,
1520 	    mss,
1521 	    segnum));
1522 
1523 	VERIFY(segnum >= 2);
1524 
1525 	/*
1526 	 * Try to pre-allocate all header messages
1527 	 */
1528 	mp_chain = NULL;
1529 	for (i = 0; i < segnum; i++) {
1530 		if ((nmp = allocb(hdrlen, 0)) == NULL) {
1531 			/* Clean up the mp_chain */
1532 			while (mp_chain != NULL) {
1533 				nmp = mp_chain;
1534 				mp_chain = mp_chain->b_next;
1535 				freemsg(nmp);
1536 			}
1537 			NXGE_DEBUG_MSG((NULL, TX_CTL,
1538 			    "<== nxge_do_softlso: "
1539 			    "Could not allocate enough messages for headers!"));
1540 			freemsg(mp);
1541 			return (NULL);
1542 		}
1543 		nmp->b_next = mp_chain;
1544 		mp_chain = nmp;
1545 
1546 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1547 		    "==> nxge_do_softlso: "
1548 		    "mp $%p nmp $%p mp_chain $%p mp_chain->b_next $%p",
1549 		    mp, nmp, mp_chain, mp_chain->b_next));
1550 	}
1551 
1552 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1553 	    "==> nxge_do_softlso: mp $%p nmp $%p mp_chain $%p",
1554 	    mp, nmp, mp_chain));
1555 
1556 	/*
1557 	 * Associate payload with new packets
1558 	 */
1559 	cmp = mp_chain;
1560 	left = available;
1561 	while (cmp != NULL) {
1562 		nmp = dupb(datamp);
1563 		if (nmp == NULL) {
1564 			do_cleanup = B_TRUE;
1565 			NXGE_DEBUG_MSG((NULL, TX_CTL,
1566 			    "==>nxge_do_softlso: "
1567 			    "Can not dupb(datamp), have to do clean up"));
1568 			goto cleanup_allocated_msgs;
1569 		}
1570 
1571 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1572 		    "==> nxge_do_softlso: (loop) before mp $%p cmp $%p "
1573 		    "dupb nmp $%p len %d left %d msd %d ",
1574 		    mp, cmp, nmp, len, left, mss));
1575 
1576 		cmp->b_cont = nmp;
1577 		nmp->b_rptr = rptr;
1578 		len = (left < mss) ? left : mss;
1579 		left -= len;
1580 
1581 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1582 		    "==> nxge_do_softlso: (loop) after mp $%p cmp $%p "
1583 		    "dupb nmp $%p len %d left %d mss %d ",
1584 		    mp, cmp, nmp, len, left, mss));
1585 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1586 		    "nxge_do_softlso: before available: %d, "
1587 		    "left: %d, len: %d, segnum: %d MBLK(nmp): %d",
1588 		    available, left, len, segnum, (int)MBLKL(nmp)));
1589 
1590 		len -= MBLKL(nmp);
1591 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1592 		    "nxge_do_softlso: after available: %d, "
1593 		    "left: %d, len: %d, segnum: %d MBLK(nmp): %d",
1594 		    available, left, len, segnum, (int)MBLKL(nmp)));
1595 
1596 		while (len > 0) {
1597 			mblk_t *mmp = NULL;
1598 
1599 			NXGE_DEBUG_MSG((NULL, TX_CTL,
1600 			    "nxge_do_softlso: (4) len > 0 available: %d, "
1601 			    "left: %d, len: %d, segnum: %d MBLK(nmp): %d",
1602 			    available, left, len, segnum, (int)MBLKL(nmp)));
1603 
1604 			if (datamp->b_cont != NULL) {
1605 				datamp = datamp->b_cont;
1606 				rptr = datamp->b_rptr;
1607 				mmp = dupb(datamp);
1608 				if (mmp == NULL) {
1609 					do_cleanup = B_TRUE;
1610 					NXGE_DEBUG_MSG((NULL, TX_CTL,
1611 					    "==> nxge_do_softlso: "
1612 					    "Can not dupb(datamp) (1), :
1613 					    "have to do clean up"));
1614 					NXGE_DEBUG_MSG((NULL, TX_CTL,
1615 					    "==> nxge_do_softlso: "
1616 					    "available: %d, left: %d, "
1617 					    "len: %d, MBLKL(nmp): %d",
1618 					    available, left, len,
1619 					    (int)MBLKL(nmp)));
1620 					goto cleanup_allocated_msgs;
1621 				}
1622 			} else {
1623 				NXGE_ERROR_MSG((NULL, NXGE_ERR_CTL,
1624 				    "==> nxge_do_softlso: "
1625 				    "(1)available: %d, left: %d, "
1626 				    "len: %d, MBLKL(nmp): %d",
1627 				    available, left, len,
1628 				    (int)MBLKL(nmp)));
1629 				cmn_err(CE_PANIC,
1630 				    "==> nxge_do_softlso: "
1631 				    "Pointers must have been corrupted!\n"
1632 				    "datamp: $%p, nmp: $%p, rptr: $%p",
1633 				    (void *)datamp,
1634 				    (void *)nmp,
1635 				    (void *)rptr);
1636 			}
1637 			nmp->b_cont = mmp;
1638 			nmp = mmp;
1639 			len -= MBLKL(nmp);
1640 		}
1641 		if (len < 0) {
1642 			nmp->b_wptr += len;
1643 			rptr = nmp->b_wptr;
1644 			NXGE_DEBUG_MSG((NULL, TX_CTL,
1645 			    "(5) len < 0 (less than 0)"
1646 			    "available: %d, left: %d, len: %d, MBLKL(nmp): %d",
1647 			    available, left, len, (int)MBLKL(nmp)));
1648 
1649 		} else if (len == 0) {
1650 			if (datamp->b_cont != NULL) {
1651 				NXGE_DEBUG_MSG((NULL, TX_CTL,
1652 				    "(5) len == 0"
1653 				    "available: %d, left: %d, len: %d, "
1654 				    "MBLKL(nmp): %d",
1655 				    available, left, len, (int)MBLKL(nmp)));
1656 				datamp = datamp->b_cont;
1657 				rptr = datamp->b_rptr;
1658 			} else {
1659 				NXGE_DEBUG_MSG((NULL, TX_CTL,
1660 				    "(6)available b_cont == NULL : %d, "
1661 				    "left: %d, len: %d, MBLKL(nmp): %d",
1662 				    available, left, len, (int)MBLKL(nmp)));
1663 
1664 				VERIFY(cmp->b_next == NULL);
1665 				VERIFY(left == 0);
1666 				break; /* Done! */
1667 			}
1668 		}
1669 		cmp = cmp->b_next;
1670 
1671 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1672 		    "(7) do_softlso: "
1673 		    "next mp in mp_chain available len != 0 : %d, "
1674 		    "left: %d, len: %d, MBLKL(nmp): %d",
1675 		    available, left, len, (int)MBLKL(nmp)));
1676 	}
1677 
1678 	/*
1679 	 * From now, start to fill up all headers for the first message
1680 	 * Hardware checksum flags need to be updated separately for FULLCKSUM
1681 	 * and PARTIALCKSUM cases. For full checksum, copy the original flags
1682 	 * into every new packet is enough. But for HCK_PARTIALCKSUM, all
1683 	 * required fields need to be updated properly.
1684 	 */
1685 	nmp = mp_chain;
1686 	bcopy(mp->b_rptr, nmp->b_rptr, hdrlen);
1687 	nmp->b_wptr = nmp->b_rptr + hdrlen;
1688 	niph = (struct ip *)(nmp->b_rptr + ehlen);
1689 	niph->ip_len = htons(mss + iphlen + tcphlen);
1690 	ip_id = ntohs(niph->ip_id);
1691 	ntcph = (struct tcphdr *)(nmp->b_rptr + ehlen + iphlen);
1692 #ifdef __sparc
1693 	bcopy((char *)&ntcph->th_seq, &tcp_seq_tmp, 4);
1694 	tcp_seq = ntohl(tcp_seq_tmp);
1695 #else
1696 	tcp_seq = ntohl(ntcph->th_seq);
1697 #endif
1698 
1699 	ntcph->th_flags &= ~(TH_FIN | TH_PUSH | TH_RST);
1700 
1701 	DB_CKSUMFLAGS(nmp) = (uint16_t)hckflags;
1702 	DB_CKSUMSTART(nmp) = start_offset;
1703 	DB_CKSUMSTUFF(nmp) = stuff_offset;
1704 
1705 	/* calculate IP checksum and TCP pseudo header checksum */
1706 	niph->ip_sum = 0;
1707 	niph->ip_sum = (uint16_t)nxge_csgen((uint16_t *)niph, iphlen);
1708 
1709 	l4_len = mss + tcphlen;
1710 	sum = htons(l4_len) + l4cksum;
1711 	sum = (sum & 0xFFFF) + (sum >> 16);
1712 	ntcph->th_sum = (sum & 0xffff);
1713 
1714 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1715 	    "==> nxge_do_softlso: first mp $%p (mp_chain $%p) "
1716 	    "mss %d pktlen %d l4_len %d (0x%x) "
1717 	    "MBLKL(mp): %d, MBLKL(datamp): %d "
1718 	    "ip_sum 0x%x "
1719 	    "th_sum 0x%x sum 0x%x ) "
1720 	    "dump first ip->tcp %s",
1721 	    nmp, mp_chain,
1722 	    mss,
1723 	    pktlen,
1724 	    l4_len,
1725 	    l4_len,
1726 	    (int)MBLKL(mp), (int)MBLKL(datamp),
1727 	    niph->ip_sum,
1728 	    ntcph->th_sum,
1729 	    sum,
1730 	    nxge_dump_packet((char *)niph, 52)));
1731 
1732 	cmp = nmp;
1733 	while ((nmp = nmp->b_next)->b_next != NULL) {
1734 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1735 		    "==>nxge_do_softlso: middle l4_len %d ", l4_len));
1736 		bcopy(cmp->b_rptr, nmp->b_rptr, hdrlen);
1737 		nmp->b_wptr = nmp->b_rptr + hdrlen;
1738 		niph = (struct ip *)(nmp->b_rptr + ehlen);
1739 		niph->ip_id = htons(++ip_id);
1740 		niph->ip_len = htons(mss + iphlen + tcphlen);
1741 		ntcph = (struct tcphdr *)(nmp->b_rptr + ehlen + iphlen);
1742 		tcp_seq += mss;
1743 
1744 		ntcph->th_flags &= ~(TH_FIN | TH_PUSH | TH_RST | TH_URG);
1745 
1746 #ifdef __sparc
1747 		tcp_seq_tmp = htonl(tcp_seq);
1748 		bcopy(&tcp_seq_tmp, (char *)&ntcph->th_seq, 4);
1749 #else
1750 		ntcph->th_seq = htonl(tcp_seq);
1751 #endif
1752 		DB_CKSUMFLAGS(nmp) = (uint16_t)hckflags;
1753 		DB_CKSUMSTART(nmp) = start_offset;
1754 		DB_CKSUMSTUFF(nmp) = stuff_offset;
1755 
1756 		/* calculate IP checksum and TCP pseudo header checksum */
1757 		niph->ip_sum = 0;
1758 		niph->ip_sum = (uint16_t)nxge_csgen((uint16_t *)niph, iphlen);
1759 		ntcph->th_sum = (sum & 0xffff);
1760 
1761 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1762 		    "==> nxge_do_softlso: middle ip_sum 0x%x "
1763 		    "th_sum 0x%x "
1764 		    " mp $%p (mp_chain $%p) pktlen %d "
1765 		    "MBLKL(mp): %d, MBLKL(datamp): %d ",
1766 		    niph->ip_sum,
1767 		    ntcph->th_sum,
1768 		    nmp, mp_chain,
1769 		    pktlen, (int)MBLKL(mp), (int)MBLKL(datamp)));
1770 	}
1771 
1772 	/* Last segment */
1773 	/*
1774 	 * Set FIN and/or PSH flags if present only in the last packet.
1775 	 * The ip_len could be different from prior packets.
1776 	 */
1777 	bcopy(cmp->b_rptr, nmp->b_rptr, hdrlen);
1778 	nmp->b_wptr = nmp->b_rptr + hdrlen;
1779 	niph = (struct ip *)(nmp->b_rptr + ehlen);
1780 	niph->ip_id = htons(++ip_id);
1781 	niph->ip_len = htons(msgsize(nmp->b_cont) + iphlen + tcphlen);
1782 	ntcph = (struct tcphdr *)(nmp->b_rptr + ehlen + iphlen);
1783 	tcp_seq += mss;
1784 #ifdef __sparc
1785 	tcp_seq_tmp = htonl(tcp_seq);
1786 	bcopy(&tcp_seq_tmp, (char *)&ntcph->th_seq, 4);
1787 #else
1788 	ntcph->th_seq = htonl(tcp_seq);
1789 #endif
1790 	ntcph->th_flags = (otcph->th_flags & ~TH_URG);
1791 
1792 	DB_CKSUMFLAGS(nmp) = (uint16_t)hckflags;
1793 	DB_CKSUMSTART(nmp) = start_offset;
1794 	DB_CKSUMSTUFF(nmp) = stuff_offset;
1795 
1796 	/* calculate IP checksum and TCP pseudo header checksum */
1797 	niph->ip_sum = 0;
1798 	niph->ip_sum = (uint16_t)nxge_csgen((uint16_t *)niph, iphlen);
1799 
1800 	l4_len = ntohs(niph->ip_len) - iphlen;
1801 	sum = htons(l4_len) + l4cksum;
1802 	sum = (sum & 0xFFFF) + (sum >> 16);
1803 	ntcph->th_sum = (sum & 0xffff);
1804 
1805 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1806 	    "==> nxge_do_softlso: last next "
1807 	    "niph->ip_sum 0x%x "
1808 	    "ntcph->th_sum 0x%x sum 0x%x "
1809 	    "dump last ip->tcp %s "
1810 	    "cmp $%p mp $%p (mp_chain $%p) pktlen %d (0x%x) "
1811 	    "l4_len %d (0x%x) "
1812 	    "MBLKL(mp): %d, MBLKL(datamp): %d ",
1813 	    niph->ip_sum,
1814 	    ntcph->th_sum, sum,
1815 	    nxge_dump_packet((char *)niph, 52),
1816 	    cmp, nmp, mp_chain,
1817 	    pktlen, pktlen,
1818 	    l4_len,
1819 	    l4_len,
1820 	    (int)MBLKL(mp), (int)MBLKL(datamp)));
1821 
1822 cleanup_allocated_msgs:
1823 	if (do_cleanup) {
1824 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1825 		    "==> nxge_do_softlso: "
1826 		    "Failed allocating messages, "
1827 		    "have to clean up and fail!"));
1828 		while (mp_chain != NULL) {
1829 			nmp = mp_chain;
1830 			mp_chain = mp_chain->b_next;
1831 			freemsg(nmp);
1832 		}
1833 	}
1834 	/*
1835 	 * We're done here, so just free the original message and return the
1836 	 * new message chain, that could be NULL if failed, back to the caller.
1837 	 */
1838 	freemsg(mp);
1839 
1840 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1841 	    "<== nxge_do_softlso:mp_chain $%p", mp_chain));
1842 	return (mp_chain);
1843 }
1844 
1845 /*
1846  * Will be called before NIC driver do further operation on the message.
1847  * The input message may include LSO information, if so, go to softlso logic
1848  * to eliminate the oversized LSO packet for the incapable underlying h/w.
1849  * The return could be the same non-LSO message or a message chain for LSO case.
1850  *
1851  * The driver needs to call this function per packet and process the whole chain
1852  * if applied.
1853  */
1854 static mblk_t *
1855 nxge_lso_eliminate(mblk_t *mp)
1856 {
1857 	uint32_t lsoflags;
1858 	uint32_t mss;
1859 
1860 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1861 	    "==>nxge_lso_eliminate:"));
1862 	nxge_lso_info_get(mp, &mss, &lsoflags);
1863 
1864 	if (lsoflags & HW_LSO) {
1865 		mblk_t *nmp;
1866 
1867 		NXGE_DEBUG_MSG((NULL, TX_CTL,
1868 		    "==>nxge_lso_eliminate:"
1869 		    "HW_LSO:mss %d mp $%p",
1870 		    mss, mp));
1871 		if ((nmp = nxge_do_softlso(mp, mss)) != NULL) {
1872 			NXGE_DEBUG_MSG((NULL, TX_CTL,
1873 			    "<== nxge_lso_eliminate: "
1874 			    "LSO: nmp not NULL nmp $%p mss %d mp $%p",
1875 			    nmp, mss, mp));
1876 			return (nmp);
1877 		} else {
1878 			NXGE_DEBUG_MSG((NULL, TX_CTL,
1879 			    "<== nxge_lso_eliminate_ "
1880 			    "LSO: failed nmp NULL nmp $%p mss %d mp $%p",
1881 			    nmp, mss, mp));
1882 			return (NULL);
1883 		}
1884 	}
1885 
1886 	NXGE_DEBUG_MSG((NULL, TX_CTL,
1887 	    "<== nxge_lso_eliminate"));
1888 	return (mp);
1889 }
1890 
1891 static uint32_t
1892 nxge_csgen(uint16_t *adr, int len)
1893 {
1894 	int		i, odd;
1895 	uint32_t	sum = 0;
1896 	uint32_t	c = 0;
1897 
1898 	odd = len % 2;
1899 	for (i = 0; i < (len / 2); i++) {
1900 		sum += (adr[i] & 0xffff);
1901 	}
1902 	if (odd) {
1903 		sum += adr[len / 2] & 0xff00;
1904 	}
1905 	while ((c = ((sum & 0xffff0000) >> 16)) != 0) {
1906 		sum &= 0xffff;
1907 		sum += c;
1908 	}
1909 	return (~sum & 0xffff);
1910 }
1911