xref: /titanic_51/usr/src/uts/common/io/nxge/nxge_send.c (revision 76b27f93c5149222cfc6babb8a5b4f1a06a4ead5)
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 2007 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 extern uint32_t		nxge_reclaim_pending;
31 extern uint32_t 	nxge_bcopy_thresh;
32 extern uint32_t 	nxge_dvma_thresh;
33 extern uint32_t 	nxge_dma_stream_thresh;
34 extern uint32_t		nxge_tx_minfree;
35 extern uint32_t		nxge_tx_intr_thres;
36 extern uint32_t		nxge_tx_max_gathers;
37 extern uint32_t		nxge_tx_tiny_pack;
38 extern uint32_t		nxge_tx_use_bcopy;
39 extern uint32_t		nxge_tx_lb_policy;
40 extern uint32_t		nxge_no_tx_lb;
41 extern nxge_tx_mode_t	nxge_tx_scheme;
42 
43 typedef struct _mac_tx_hint {
44 	uint16_t	sap;
45 	uint16_t	vid;
46 	void		*hash;
47 } mac_tx_hint_t, *p_mac_tx_hint_t;
48 
49 int nxge_tx_lb_ring_1(p_mblk_t, uint32_t, p_mac_tx_hint_t);
50 
51 int
52 nxge_start(p_nxge_t nxgep, p_tx_ring_t tx_ring_p, p_mblk_t mp)
53 {
54 	int 			status = 0;
55 	p_tx_desc_t 		tx_desc_ring_vp;
56 	npi_handle_t		npi_desc_handle;
57 	nxge_os_dma_handle_t 	tx_desc_dma_handle;
58 	p_tx_desc_t 		tx_desc_p;
59 	p_tx_msg_t 		tx_msg_ring;
60 	p_tx_msg_t 		tx_msg_p;
61 	tx_desc_t		tx_desc, *tmp_desc_p;
62 	tx_desc_t		sop_tx_desc, *sop_tx_desc_p;
63 	p_tx_pkt_header_t	hdrp;
64 	p_tx_pkt_hdr_all_t	pkthdrp;
65 	uint8_t			npads = 0;
66 	uint64_t 		dma_ioaddr;
67 	uint32_t		dma_flags;
68 	int			last_bidx;
69 	uint8_t 		*b_rptr;
70 	caddr_t 		kaddr;
71 	uint32_t		nmblks;
72 	uint32_t		ngathers;
73 	uint32_t		clen;
74 	int 			len;
75 	uint32_t		pkt_len, pack_len, min_len;
76 	uint32_t		bcopy_thresh;
77 	int 			i, cur_index, sop_index;
78 	uint16_t		tail_index;
79 	boolean_t		tail_wrap = B_FALSE;
80 	nxge_dma_common_t	desc_area;
81 	nxge_os_dma_handle_t 	dma_handle;
82 	ddi_dma_cookie_t 	dma_cookie;
83 	npi_handle_t		npi_handle;
84 	p_mblk_t 		nmp;
85 	p_mblk_t		t_mp;
86 	uint32_t 		ncookies;
87 	boolean_t 		good_packet;
88 	boolean_t 		mark_mode = B_FALSE;
89 	p_nxge_stats_t 		statsp;
90 	p_nxge_tx_ring_stats_t tdc_stats;
91 	t_uscalar_t 		start_offset = 0;
92 	t_uscalar_t 		stuff_offset = 0;
93 	t_uscalar_t 		end_offset = 0;
94 	t_uscalar_t 		value = 0;
95 	t_uscalar_t 		cksum_flags = 0;
96 	boolean_t		cksum_on = B_FALSE;
97 	uint32_t		boff = 0;
98 	uint64_t		tot_xfer_len = 0, tmp_len = 0;
99 	boolean_t		header_set = B_FALSE;
100 #ifdef NXGE_DEBUG
101 	p_tx_desc_t 		tx_desc_ring_pp;
102 	p_tx_desc_t 		tx_desc_pp;
103 	tx_desc_t		*save_desc_p;
104 	int			dump_len;
105 	int			sad_len;
106 	uint64_t		sad;
107 	int			xfer_len;
108 	uint32_t		msgsize;
109 #endif
110 
111 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
112 		"==> nxge_start: tx dma channel %d", tx_ring_p->tdc));
113 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
114 		"==> nxge_start: Starting tdc %d desc pending %d",
115 		tx_ring_p->tdc, tx_ring_p->descs_pending));
116 
117 	statsp = nxgep->statsp;
118 
119 	if (nxgep->statsp->port_stats.lb_mode == nxge_lb_normal) {
120 		if (!statsp->mac_stats.link_up) {
121 			freemsg(mp);
122 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
123 				"link not up or LB mode"));
124 			goto nxge_start_fail1;
125 		}
126 	}
127 
128 	hcksum_retrieve(mp, NULL, NULL, &start_offset,
129 		&stuff_offset, &end_offset, &value, &cksum_flags);
130 	if (!NXGE_IS_VLAN_PACKET(mp->b_rptr)) {
131 		start_offset += sizeof (ether_header_t);
132 		stuff_offset += sizeof (ether_header_t);
133 	} else {
134 		start_offset += sizeof (struct ether_vlan_header);
135 		stuff_offset += sizeof (struct ether_vlan_header);
136 	}
137 
138 	if (cksum_flags & HCK_PARTIALCKSUM) {
139 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
140 			"==> nxge_start: cksum_flags 0x%x (partial checksum) ",
141 			cksum_flags));
142 		cksum_on = B_TRUE;
143 	}
144 
145 #ifdef	NXGE_DEBUG
146 	if (tx_ring_p->descs_pending) {
147 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
148 			"desc pending %d ", tx_ring_p->descs_pending));
149 	}
150 
151 	dump_len = (int)(MBLKL(mp));
152 	dump_len = (dump_len > 128) ? 128: dump_len;
153 
154 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
155 		"==> nxge_start: tdc %d: dumping ...: b_rptr $%p "
156 		"(Before header reserve: ORIGINAL LEN %d)",
157 		tx_ring_p->tdc,
158 		mp->b_rptr,
159 		dump_len));
160 
161 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: dump packets "
162 		"(IP ORIGINAL b_rptr $%p): %s", mp->b_rptr,
163 		nxge_dump_packet((char *)mp->b_rptr, dump_len)));
164 #endif
165 
166 	MUTEX_ENTER(&tx_ring_p->lock);
167 	tdc_stats = tx_ring_p->tdc_stats;
168 	mark_mode = (tx_ring_p->descs_pending &&
169 		((tx_ring_p->tx_ring_size - tx_ring_p->descs_pending)
170 		< nxge_tx_minfree));
171 
172 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
173 		"TX Descriptor ring is channel %d mark mode %d",
174 		tx_ring_p->tdc, mark_mode));
175 
176 	if (!nxge_txdma_reclaim(nxgep, tx_ring_p, nxge_tx_minfree)) {
177 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
178 			"TX Descriptor ring is full: channel %d",
179 			tx_ring_p->tdc));
180 		cas32((uint32_t *)&tx_ring_p->queueing, 0, 1);
181 		tdc_stats->tx_no_desc++;
182 		MUTEX_EXIT(&tx_ring_p->lock);
183 		if (nxgep->resched_needed && !nxgep->resched_running) {
184 			nxgep->resched_running = B_TRUE;
185 			ddi_trigger_softintr(nxgep->resched_id);
186 		}
187 		status = 1;
188 		goto nxge_start_fail1;
189 	}
190 
191 	nmp = mp;
192 	i = sop_index = tx_ring_p->wr_index;
193 	nmblks = 0;
194 	ngathers = 0;
195 	pkt_len = 0;
196 	pack_len = 0;
197 	clen = 0;
198 	last_bidx = -1;
199 	good_packet = B_TRUE;
200 
201 	desc_area = tx_ring_p->tdc_desc;
202 	npi_handle = desc_area.npi_handle;
203 	npi_desc_handle.regh = (nxge_os_acc_handle_t)
204 			DMA_COMMON_ACC_HANDLE(desc_area);
205 	tx_desc_ring_vp = (p_tx_desc_t)DMA_COMMON_VPTR(desc_area);
206 #ifdef	NXGE_DEBUG
207 	tx_desc_ring_pp = (p_tx_desc_t)DMA_COMMON_IOADDR(desc_area);
208 #endif
209 	tx_desc_dma_handle = (nxge_os_dma_handle_t)
210 			DMA_COMMON_HANDLE(desc_area);
211 	tx_msg_ring = tx_ring_p->tx_msg_ring;
212 
213 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: wr_index %d i %d",
214 		sop_index, i));
215 
216 #ifdef	NXGE_DEBUG
217 	msgsize = msgdsize(nmp);
218 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
219 		"==> nxge_start(1): wr_index %d i %d msgdsize %d",
220 		sop_index, i, msgsize));
221 #endif
222 	/*
223 	 * The first 16 bytes of the premapped buffer are reserved
224 	 * for header. No padding will be used.
225 	 */
226 	pkt_len = pack_len = boff = TX_PKT_HEADER_SIZE;
227 	if (nxge_tx_use_bcopy && (nxgep->niu_type != N2_NIU)) {
228 		bcopy_thresh = (nxge_bcopy_thresh - TX_PKT_HEADER_SIZE);
229 	} else {
230 		bcopy_thresh = (TX_BCOPY_SIZE - TX_PKT_HEADER_SIZE);
231 	}
232 	while (nmp) {
233 		good_packet = B_TRUE;
234 		b_rptr = nmp->b_rptr;
235 		len = MBLKL(nmp);
236 		if (len <= 0) {
237 			nmp = nmp->b_cont;
238 			continue;
239 		}
240 		nmblks++;
241 
242 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(1): nmblks %d "
243 			"len %d pkt_len %d pack_len %d",
244 			nmblks, len, pkt_len, pack_len));
245 		/*
246 		 * Hardware limits the transfer length to 4K for NIU and
247 		 * 4076 (TX_MAX_TRANSFER_LENGTH) for Neptune. But we just
248 		 * use TX_MAX_TRANSFER_LENGTH as the limit for both.
249 		 * If len is longer than the limit, then we break nmp into
250 		 * two chunks: Make the first chunk equal to the limit and
251 		 * the second chunk for the remaining data. If the second
252 		 * chunk is still larger than the limit, then it will be
253 		 * broken into two in the next pass.
254 		 */
255 		if (len > TX_MAX_TRANSFER_LENGTH - TX_PKT_HEADER_SIZE) {
256 			if ((t_mp = dupb(nmp)) != NULL) {
257 				nmp->b_wptr = nmp->b_rptr +
258 				    (TX_MAX_TRANSFER_LENGTH
259 				    - TX_PKT_HEADER_SIZE);
260 				t_mp->b_rptr = nmp->b_wptr;
261 				t_mp->b_cont = nmp->b_cont;
262 				nmp->b_cont = t_mp;
263 				len = MBLKL(nmp);
264 			} else {
265 				good_packet = B_FALSE;
266 				goto nxge_start_fail2;
267 			}
268 		}
269 		tx_desc.value = 0;
270 		tx_desc_p = &tx_desc_ring_vp[i];
271 #ifdef	NXGE_DEBUG
272 		tx_desc_pp = &tx_desc_ring_pp[i];
273 #endif
274 		tx_msg_p = &tx_msg_ring[i];
275 #if defined(__i386)
276 		npi_desc_handle.regp = (uint32_t)tx_desc_p;
277 #else
278 		npi_desc_handle.regp = (uint64_t)tx_desc_p;
279 #endif
280 		if (!header_set &&
281 			((!nxge_tx_use_bcopy && (len > TX_BCOPY_SIZE)) ||
282 				(len >= bcopy_thresh))) {
283 			header_set = B_TRUE;
284 			bcopy_thresh += TX_PKT_HEADER_SIZE;
285 			boff = 0;
286 			pack_len = 0;
287 			kaddr = (caddr_t)DMA_COMMON_VPTR(tx_msg_p->buf_dma);
288 			hdrp = (p_tx_pkt_header_t)kaddr;
289 			clen = pkt_len;
290 			dma_handle = tx_msg_p->buf_dma_handle;
291 			dma_ioaddr = DMA_COMMON_IOADDR(tx_msg_p->buf_dma);
292 			(void) ddi_dma_sync(dma_handle,
293 				i * nxge_bcopy_thresh, nxge_bcopy_thresh,
294 				DDI_DMA_SYNC_FORDEV);
295 
296 			tx_msg_p->flags.dma_type = USE_BCOPY;
297 			goto nxge_start_control_header_only;
298 		}
299 
300 		pkt_len += len;
301 		pack_len += len;
302 
303 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(3): "
304 			"desc entry %d "
305 			"DESC IOADDR $%p "
306 			"desc_vp $%p tx_desc_p $%p "
307 			"desc_pp $%p tx_desc_pp $%p "
308 			"len %d pkt_len %d pack_len %d",
309 			i,
310 			DMA_COMMON_IOADDR(desc_area),
311 			tx_desc_ring_vp, tx_desc_p,
312 			tx_desc_ring_pp, tx_desc_pp,
313 			len, pkt_len, pack_len));
314 
315 		if (len < bcopy_thresh) {
316 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(4): "
317 				"USE BCOPY: "));
318 			if (nxge_tx_tiny_pack) {
319 				uint32_t blst =
320 					TXDMA_DESC_NEXT_INDEX(i, -1,
321 						tx_ring_p->tx_wrap_mask);
322 				NXGE_DEBUG_MSG((nxgep, TX_CTL,
323 					"==> nxge_start(5): pack"));
324 				if ((pack_len <= bcopy_thresh) &&
325 					(last_bidx == blst)) {
326 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
327 						"==> nxge_start: pack(6) "
328 						"(pkt_len %d pack_len %d)",
329 						pkt_len, pack_len));
330 					i = blst;
331 					tx_desc_p = &tx_desc_ring_vp[i];
332 #ifdef	NXGE_DEBUG
333 					tx_desc_pp = &tx_desc_ring_pp[i];
334 #endif
335 					tx_msg_p = &tx_msg_ring[i];
336 					boff = pack_len - len;
337 					ngathers--;
338 				} else if (pack_len > bcopy_thresh &&
339 					header_set) {
340 					pack_len = len;
341 					boff = 0;
342 					bcopy_thresh = nxge_bcopy_thresh;
343 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
344 						"==> nxge_start(7): > max NEW "
345 						"bcopy thresh %d "
346 						"pkt_len %d pack_len %d(next)",
347 						bcopy_thresh,
348 						pkt_len, pack_len));
349 				}
350 				last_bidx = i;
351 			}
352 			kaddr = (caddr_t)DMA_COMMON_VPTR(tx_msg_p->buf_dma);
353 			if ((boff == TX_PKT_HEADER_SIZE) && (nmblks == 1)) {
354 				hdrp = (p_tx_pkt_header_t)kaddr;
355 				header_set = B_TRUE;
356 				NXGE_DEBUG_MSG((nxgep, TX_CTL,
357 					"==> nxge_start(7_x2): "
358 					"pkt_len %d pack_len %d (new hdrp $%p)",
359 					pkt_len, pack_len, hdrp));
360 			}
361 			tx_msg_p->flags.dma_type = USE_BCOPY;
362 			kaddr += boff;
363 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(8): "
364 				"USE BCOPY: before bcopy "
365 				"DESC IOADDR $%p entry %d "
366 				"bcopy packets %d "
367 				"bcopy kaddr $%p "
368 				"bcopy ioaddr (SAD) $%p "
369 				"bcopy clen %d "
370 				"bcopy boff %d",
371 				DMA_COMMON_IOADDR(desc_area), i,
372 				tdc_stats->tx_hdr_pkts,
373 				kaddr,
374 				dma_ioaddr,
375 				clen,
376 				boff));
377 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
378 				"1USE BCOPY: "));
379 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
380 				"2USE BCOPY: "));
381 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: "
382 				"last USE BCOPY: copy from b_rptr $%p "
383 				"to KADDR $%p (len %d offset %d",
384 				b_rptr, kaddr, len, boff));
385 
386 			bcopy(b_rptr, kaddr, len);
387 
388 #ifdef	NXGE_DEBUG
389 			dump_len = (len > 128) ? 128: len;
390 			NXGE_DEBUG_MSG((nxgep, TX_CTL,
391 				"==> nxge_start: dump packets "
392 				"(After BCOPY len %d)"
393 				"(b_rptr $%p): %s", len, nmp->b_rptr,
394 				nxge_dump_packet((char *)nmp->b_rptr,
395 				dump_len)));
396 #endif
397 
398 			dma_handle = tx_msg_p->buf_dma_handle;
399 			dma_ioaddr = DMA_COMMON_IOADDR(tx_msg_p->buf_dma);
400 			(void) ddi_dma_sync(dma_handle,
401 				i * nxge_bcopy_thresh, nxge_bcopy_thresh,
402 					DDI_DMA_SYNC_FORDEV);
403 			clen = len + boff;
404 			tdc_stats->tx_hdr_pkts++;
405 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(9): "
406 				"USE BCOPY: "
407 				"DESC IOADDR $%p entry %d "
408 				"bcopy packets %d "
409 				"bcopy kaddr $%p "
410 				"bcopy ioaddr (SAD) $%p "
411 				"bcopy clen %d "
412 				"bcopy boff %d",
413 				DMA_COMMON_IOADDR(desc_area),
414 				i,
415 				tdc_stats->tx_hdr_pkts,
416 				kaddr,
417 				dma_ioaddr,
418 				clen,
419 				boff));
420 		} else {
421 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(12): "
422 				"USE DVMA: len %d", len));
423 			tx_msg_p->flags.dma_type = USE_DMA;
424 			dma_flags = DDI_DMA_WRITE;
425 			if (len < nxge_dma_stream_thresh) {
426 				dma_flags |= DDI_DMA_CONSISTENT;
427 			} else {
428 				dma_flags |= DDI_DMA_STREAMING;
429 			}
430 
431 			dma_handle = tx_msg_p->dma_handle;
432 			status = ddi_dma_addr_bind_handle(dma_handle, NULL,
433 				(caddr_t)b_rptr, len, dma_flags,
434 				DDI_DMA_DONTWAIT, NULL,
435 				&dma_cookie, &ncookies);
436 			if (status == DDI_DMA_MAPPED) {
437 				dma_ioaddr = dma_cookie.dmac_laddress;
438 				len = (int)dma_cookie.dmac_size;
439 				clen = (uint32_t)dma_cookie.dmac_size;
440 				NXGE_DEBUG_MSG((nxgep, TX_CTL,
441 					"==> nxge_start(12_1): "
442 					"USE DVMA: len %d clen %d "
443 					"ngathers %d",
444 					len, clen,
445 					ngathers));
446 #if defined(__i386)
447 				npi_desc_handle.regp = (uint32_t)tx_desc_p;
448 #else
449 				npi_desc_handle.regp = (uint64_t)tx_desc_p;
450 #endif
451 				while (ncookies > 1) {
452 					ngathers++;
453 					/*
454 					 * this is the fix for multiple
455 					 * cookies, which are basicaly
456 					 * a descriptor entry, we don't set
457 					 * SOP bit as well as related fields
458 					 */
459 
460 					(void) npi_txdma_desc_gather_set(
461 						npi_desc_handle,
462 						&tx_desc,
463 						(ngathers -1),
464 						mark_mode,
465 						ngathers,
466 						dma_ioaddr,
467 						clen);
468 
469 					tx_msg_p->tx_msg_size = clen;
470 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
471 						"==> nxge_start:  DMA "
472 						"ncookie %d "
473 						"ngathers %d "
474 						"dma_ioaddr $%p len %d"
475 						"desc $%p descp $%p (%d)",
476 						ncookies,
477 						ngathers,
478 						dma_ioaddr, clen,
479 						*tx_desc_p, tx_desc_p, i));
480 
481 					ddi_dma_nextcookie(dma_handle,
482 							&dma_cookie);
483 					dma_ioaddr =
484 						dma_cookie.dmac_laddress;
485 
486 					len = (int)dma_cookie.dmac_size;
487 					clen = (uint32_t)dma_cookie.dmac_size;
488 					NXGE_DEBUG_MSG((nxgep, TX_CTL,
489 						"==> nxge_start(12_2): "
490 						"USE DVMA: len %d clen %d ",
491 						len, clen));
492 
493 					i = TXDMA_DESC_NEXT_INDEX(i, 1,
494 						tx_ring_p->tx_wrap_mask);
495 					tx_desc_p = &tx_desc_ring_vp[i];
496 
497 					npi_desc_handle.regp =
498 #if defined(__i386)
499 						(uint32_t)tx_desc_p;
500 #else
501 						(uint64_t)tx_desc_p;
502 #endif
503 					tx_msg_p = &tx_msg_ring[i];
504 					tx_msg_p->flags.dma_type = USE_NONE;
505 					tx_desc.value = 0;
506 
507 					ncookies--;
508 				}
509 				tdc_stats->tx_ddi_pkts++;
510 				NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start:"
511 					"DMA: ddi packets %d",
512 					tdc_stats->tx_ddi_pkts));
513 			} else {
514 				NXGE_ERROR_MSG((nxgep, NXGE_ERR_CTL,
515 				    "dma mapping failed for %d "
516 				    "bytes addr $%p flags %x (%d)",
517 				    len, b_rptr, status, status));
518 				good_packet = B_FALSE;
519 				tdc_stats->tx_dma_bind_fail++;
520 				tx_msg_p->flags.dma_type = USE_NONE;
521 				goto nxge_start_fail2;
522 			}
523 		} /* ddi dvma */
524 
525 		nmp = nmp->b_cont;
526 nxge_start_control_header_only:
527 #if defined(__i386)
528 		npi_desc_handle.regp = (uint32_t)tx_desc_p;
529 #else
530 		npi_desc_handle.regp = (uint64_t)tx_desc_p;
531 #endif
532 		ngathers++;
533 
534 		if (ngathers == 1) {
535 #ifdef	NXGE_DEBUG
536 			save_desc_p = &sop_tx_desc;
537 #endif
538 			sop_tx_desc_p = &sop_tx_desc;
539 			sop_tx_desc_p->value = 0;
540 			sop_tx_desc_p->bits.hdw.tr_len = clen;
541 			sop_tx_desc_p->bits.hdw.sad = dma_ioaddr >> 32;
542 			sop_tx_desc_p->bits.ldw.sad = dma_ioaddr & 0xffffffff;
543 		} else {
544 #ifdef	NXGE_DEBUG
545 			save_desc_p = &tx_desc;
546 #endif
547 			tmp_desc_p = &tx_desc;
548 			tmp_desc_p->value = 0;
549 			tmp_desc_p->bits.hdw.tr_len = clen;
550 			tmp_desc_p->bits.hdw.sad = dma_ioaddr >> 32;
551 			tmp_desc_p->bits.ldw.sad = dma_ioaddr & 0xffffffff;
552 
553 			tx_desc_p->value = tmp_desc_p->value;
554 		}
555 
556 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(13): "
557 			"Desc_entry %d ngathers %d "
558 			"desc_vp $%p tx_desc_p $%p "
559 			"len %d clen %d pkt_len %d pack_len %d nmblks %d "
560 			"dma_ioaddr (SAD) $%p mark %d",
561 			i, ngathers,
562 			tx_desc_ring_vp, tx_desc_p,
563 			len, clen, pkt_len, pack_len, nmblks,
564 			dma_ioaddr, mark_mode));
565 
566 #ifdef NXGE_DEBUG
567 		npi_desc_handle.nxgep = nxgep;
568 		npi_desc_handle.function.function = nxgep->function_num;
569 		npi_desc_handle.function.instance = nxgep->instance;
570 		sad = (save_desc_p->value & TX_PKT_DESC_SAD_MASK);
571 		xfer_len = ((save_desc_p->value & TX_PKT_DESC_TR_LEN_MASK) >>
572 			TX_PKT_DESC_TR_LEN_SHIFT);
573 
574 
575 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "\n\t: value 0x%llx\n"
576 			"\t\tsad $%p\ttr_len %d len %d\tnptrs %d\t"
577 			"mark %d sop %d\n",
578 			save_desc_p->value,
579 			sad,
580 			save_desc_p->bits.hdw.tr_len,
581 			xfer_len,
582 			save_desc_p->bits.hdw.num_ptr,
583 			save_desc_p->bits.hdw.mark,
584 			save_desc_p->bits.hdw.sop));
585 
586 		npi_txdma_dump_desc_one(npi_desc_handle, NULL, i);
587 #endif
588 
589 		tx_msg_p->tx_msg_size = clen;
590 		i = TXDMA_DESC_NEXT_INDEX(i, 1, tx_ring_p->tx_wrap_mask);
591 		if (ngathers > nxge_tx_max_gathers) {
592 			good_packet = B_FALSE;
593 			hcksum_retrieve(mp, NULL, NULL, &start_offset,
594 				&stuff_offset, &end_offset, &value,
595 				&cksum_flags);
596 
597 			NXGE_DEBUG_MSG((NULL, TX_CTL,
598 				"==> nxge_start(14): pull msg - "
599 				"len %d pkt_len %d ngathers %d",
600 				len, pkt_len, ngathers));
601 			/* Pull all message blocks from b_cont */
602 			if ((msgpullup(mp, -1)) == NULL) {
603 				goto nxge_start_fail2;
604 			}
605 			goto nxge_start_fail2;
606 		}
607 	} /* while (nmp) */
608 
609 	tx_msg_p->tx_message = mp;
610 	tx_desc_p = &tx_desc_ring_vp[sop_index];
611 #if defined(__i386)
612 	npi_desc_handle.regp = (uint32_t)tx_desc_p;
613 #else
614 	npi_desc_handle.regp = (uint64_t)tx_desc_p;
615 #endif
616 
617 	pkthdrp = (p_tx_pkt_hdr_all_t)hdrp;
618 	pkthdrp->reserved = 0;
619 	hdrp->value = 0;
620 	(void) nxge_fill_tx_hdr(mp, B_FALSE, cksum_on,
621 		(pkt_len - TX_PKT_HEADER_SIZE), npads, pkthdrp);
622 
623 	if (pkt_len > NXGE_MTU_DEFAULT_MAX) {
624 		tdc_stats->tx_jumbo_pkts++;
625 	}
626 
627 	min_len = (nxgep->msg_min + TX_PKT_HEADER_SIZE + (npads * 2));
628 	if (pkt_len < min_len) {
629 		/* Assume we use bcopy to premapped buffers */
630 		kaddr = (caddr_t)DMA_COMMON_VPTR(tx_msg_p->buf_dma);
631 		NXGE_DEBUG_MSG((NULL, TX_CTL,
632 			"==> nxge_start(14-1): < (msg_min + 16)"
633 			"len %d pkt_len %d min_len %d bzero %d ngathers %d",
634 			len, pkt_len, min_len, (min_len - pkt_len), ngathers));
635 		bzero((kaddr + pkt_len), (min_len - pkt_len));
636 		pkt_len = tx_msg_p->tx_msg_size = min_len;
637 
638 		sop_tx_desc_p->bits.hdw.tr_len = min_len;
639 
640 		NXGE_MEM_PIO_WRITE64(npi_desc_handle, sop_tx_desc_p->value);
641 		tx_desc_p->value = sop_tx_desc_p->value;
642 
643 		NXGE_DEBUG_MSG((NULL, TX_CTL,
644 			"==> nxge_start(14-2): < msg_min - "
645 			"len %d pkt_len %d min_len %d ngathers %d",
646 			len, pkt_len, min_len, ngathers));
647 	}
648 
649 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: cksum_flags 0x%x ",
650 		cksum_flags));
651 	if (cksum_flags & HCK_PARTIALCKSUM) {
652 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
653 			"==> nxge_start: cksum_flags 0x%x (partial checksum) ",
654 			cksum_flags));
655 		cksum_on = B_TRUE;
656 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
657 			"==> nxge_start: from IP cksum_flags 0x%x "
658 			"(partial checksum) "
659 			"start_offset %d stuff_offset %d",
660 			cksum_flags, start_offset, stuff_offset));
661 		tmp_len = (uint64_t)(start_offset >> 1);
662 		hdrp->value |= (tmp_len << TX_PKT_HEADER_L4START_SHIFT);
663 		tmp_len = (uint64_t)(stuff_offset >> 1);
664 		hdrp->value |= (tmp_len << TX_PKT_HEADER_L4STUFF_SHIFT);
665 
666 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
667 			"==> nxge_start: from IP cksum_flags 0x%x "
668 			"(partial checksum) "
669 			"after SHIFT start_offset %d stuff_offset %d",
670 			cksum_flags, start_offset, stuff_offset));
671 	}
672 	{
673 		uint64_t	tmp_len;
674 
675 		/* pkt_len already includes 16 + paddings!! */
676 		/* Update the control header length */
677 		tot_xfer_len = (pkt_len - TX_PKT_HEADER_SIZE);
678 		tmp_len = hdrp->value |
679 			(tot_xfer_len << TX_PKT_HEADER_TOT_XFER_LEN_SHIFT);
680 
681 		NXGE_DEBUG_MSG((nxgep, TX_CTL,
682 			"==> nxge_start(15_x1): setting SOP "
683 			"tot_xfer_len 0x%llx (%d) pkt_len %d tmp_len "
684 			"0x%llx hdrp->value 0x%llx",
685 			tot_xfer_len, tot_xfer_len, pkt_len,
686 			tmp_len, hdrp->value));
687 #if defined(_BIG_ENDIAN)
688 		hdrp->value = ddi_swap64(tmp_len);
689 #else
690 		hdrp->value = tmp_len;
691 #endif
692 		NXGE_DEBUG_MSG((nxgep,
693 			TX_CTL, "==> nxge_start(15_x2): setting SOP "
694 			"after SWAP: tot_xfer_len 0x%llx pkt_len %d "
695 			"tmp_len 0x%llx hdrp->value 0x%llx",
696 			tot_xfer_len, pkt_len,
697 			tmp_len, hdrp->value));
698 	}
699 
700 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(15): setting SOP "
701 		"wr_index %d "
702 		"tot_xfer_len (%d) pkt_len %d npads %d",
703 		sop_index,
704 		tot_xfer_len, pkt_len,
705 		npads));
706 
707 	sop_tx_desc_p->bits.hdw.sop = 1;
708 	sop_tx_desc_p->bits.hdw.mark = mark_mode;
709 	sop_tx_desc_p->bits.hdw.num_ptr = ngathers;
710 
711 	NXGE_MEM_PIO_WRITE64(npi_desc_handle, sop_tx_desc_p->value);
712 
713 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start(16): set SOP done"));
714 
715 #ifdef NXGE_DEBUG
716 	npi_desc_handle.nxgep = nxgep;
717 	npi_desc_handle.function.function = nxgep->function_num;
718 	npi_desc_handle.function.instance = nxgep->instance;
719 
720 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "\n\t: value 0x%llx\n"
721 		"\t\tsad $%p\ttr_len %d len %d\tnptrs %d\tmark %d sop %d\n",
722 		save_desc_p->value,
723 		sad,
724 		save_desc_p->bits.hdw.tr_len,
725 		xfer_len,
726 		save_desc_p->bits.hdw.num_ptr,
727 		save_desc_p->bits.hdw.mark,
728 		save_desc_p->bits.hdw.sop));
729 	(void) npi_txdma_dump_desc_one(npi_desc_handle, NULL, sop_index);
730 
731 	dump_len = (pkt_len > 128) ? 128: pkt_len;
732 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
733 		"==> nxge_start: dump packets(17) (after sop set, len "
734 		" (len/dump_len/pkt_len/tot_xfer_len) %d/%d/%d/%d):\n"
735 		"ptr $%p: %s", len, dump_len, pkt_len, tot_xfer_len,
736 		(char *)hdrp,
737 		nxge_dump_packet((char *)hdrp, dump_len)));
738 	NXGE_DEBUG_MSG((nxgep, TX_CTL,
739 		"==> nxge_start(18): TX desc sync: sop_index %d",
740 			sop_index));
741 #endif
742 
743 	if ((ngathers == 1) || tx_ring_p->wr_index < i) {
744 		(void) ddi_dma_sync(tx_desc_dma_handle,
745 			sop_index * sizeof (tx_desc_t),
746 			ngathers * sizeof (tx_desc_t),
747 			DDI_DMA_SYNC_FORDEV);
748 
749 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "nxge_start(19): sync 1 "
750 			"cs_off = 0x%02X cs_s_off = 0x%02X "
751 			"pkt_len %d ngathers %d sop_index %d\n",
752 			stuff_offset, start_offset,
753 			pkt_len, ngathers, sop_index));
754 	} else { /* more than one descriptor and wrap around */
755 		uint32_t nsdescs = tx_ring_p->tx_ring_size - sop_index;
756 		(void) ddi_dma_sync(tx_desc_dma_handle,
757 			sop_index * sizeof (tx_desc_t),
758 			nsdescs * sizeof (tx_desc_t),
759 			DDI_DMA_SYNC_FORDEV);
760 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "nxge_start(20): sync 1 "
761 			"cs_off = 0x%02X cs_s_off = 0x%02X "
762 			"pkt_len %d ngathers %d sop_index %d\n",
763 			stuff_offset, start_offset,
764 				pkt_len, ngathers, sop_index));
765 
766 		(void) ddi_dma_sync(tx_desc_dma_handle,
767 			0,
768 			(ngathers - nsdescs) * sizeof (tx_desc_t),
769 			DDI_DMA_SYNC_FORDEV);
770 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "nxge_start(21): sync 2 "
771 			"cs_off = 0x%02X cs_s_off = 0x%02X "
772 			"pkt_len %d ngathers %d sop_index %d\n",
773 			stuff_offset, start_offset,
774 			pkt_len, ngathers, sop_index));
775 	}
776 
777 	tail_index = tx_ring_p->wr_index;
778 	tail_wrap = tx_ring_p->wr_index_wrap;
779 
780 	tx_ring_p->wr_index = i;
781 	if (tx_ring_p->wr_index <= tail_index) {
782 		tx_ring_p->wr_index_wrap = ((tail_wrap == B_TRUE) ?
783 						B_FALSE : B_TRUE);
784 	}
785 
786 	tx_ring_p->descs_pending += ngathers;
787 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: TX kick: "
788 		"channel %d wr_index %d wrap %d ngathers %d desc_pend %d",
789 		tx_ring_p->tdc,
790 		tx_ring_p->wr_index,
791 		tx_ring_p->wr_index_wrap,
792 		ngathers,
793 		tx_ring_p->descs_pending));
794 
795 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: TX KICKING: "));
796 
797 	{
798 		tx_ring_kick_t		kick;
799 
800 		kick.value = 0;
801 		kick.bits.ldw.wrap = tx_ring_p->wr_index_wrap;
802 		kick.bits.ldw.tail = (uint16_t)tx_ring_p->wr_index;
803 
804 		/* Kick start the Transmit kick register */
805 		TXDMA_REG_WRITE64(NXGE_DEV_NPI_HANDLE(nxgep),
806 			TX_RING_KICK_REG,
807 			(uint8_t)tx_ring_p->tdc,
808 			kick.value);
809 	}
810 
811 	tdc_stats->tx_starts++;
812 
813 	MUTEX_EXIT(&tx_ring_p->lock);
814 
815 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "<== nxge_start"));
816 
817 	return (status);
818 
819 nxge_start_fail2:
820 	if (good_packet == B_FALSE) {
821 		cur_index = sop_index;
822 		NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_start: clean up"));
823 		for (i = 0; i < ngathers; i++) {
824 			tx_desc_p = &tx_desc_ring_vp[cur_index];
825 #if defined(__i386)
826 			npi_handle.regp = (uint32_t)tx_desc_p;
827 #else
828 			npi_handle.regp = (uint64_t)tx_desc_p;
829 #endif
830 			tx_msg_p = &tx_msg_ring[cur_index];
831 			(void) npi_txdma_desc_set_zero(npi_handle, 1);
832 			if (tx_msg_p->flags.dma_type == USE_DVMA) {
833 				NXGE_DEBUG_MSG((nxgep, TX_CTL,
834 				    "tx_desc_p = %X index = %d",
835 				    tx_desc_p, tx_ring_p->rd_index));
836 				(void) dvma_unload(tx_msg_p->dvma_handle,
837 				    0, -1);
838 				tx_msg_p->dvma_handle = NULL;
839 				if (tx_ring_p->dvma_wr_index ==
840 				    tx_ring_p->dvma_wrap_mask)
841 					tx_ring_p->dvma_wr_index = 0;
842 				else
843 					tx_ring_p->dvma_wr_index++;
844 				tx_ring_p->dvma_pending--;
845 			} else if (tx_msg_p->flags.dma_type == USE_DMA) {
846 				if (ddi_dma_unbind_handle(
847 				    tx_msg_p->dma_handle)) {
848 					cmn_err(CE_WARN, "!nxge_start: "
849 					    "ddi_dma_unbind_handle failed");
850 				}
851 			}
852 			tx_msg_p->flags.dma_type = USE_NONE;
853 			cur_index = TXDMA_DESC_NEXT_INDEX(cur_index, 1,
854 				tx_ring_p->tx_wrap_mask);
855 
856 		}
857 
858 		nxgep->resched_needed = B_TRUE;
859 	}
860 
861 	MUTEX_EXIT(&tx_ring_p->lock);
862 
863 nxge_start_fail1:
864 	/* Add FMA to check the access handle nxge_hregh */
865 
866 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "<== nxge_start"));
867 
868 	return (status);
869 }
870 
871 int
872 nxge_serial_tx(mblk_t *mp, void *arg)
873 {
874 	p_tx_ring_t		tx_ring_p = (p_tx_ring_t)arg;
875 	p_nxge_t		nxgep = tx_ring_p->nxgep;
876 
877 	return (nxge_start(nxgep, tx_ring_p, mp));
878 }
879 
880 boolean_t
881 nxge_send(p_nxge_t nxgep, mblk_t *mp, p_mac_tx_hint_t hp)
882 {
883 	p_tx_ring_t 		*tx_rings;
884 	uint8_t			ring_index;
885 	p_tx_ring_t		tx_ring_p;
886 
887 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_send"));
888 
889 	ASSERT(mp->b_next == NULL);
890 
891 	ring_index = nxge_tx_lb_ring_1(mp, nxgep->max_tdcs, hp);
892 	tx_rings = nxgep->tx_rings->rings;
893 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_tx_msg: tx_rings $%p",
894 		tx_rings));
895 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_tx_msg: max_tdcs %d "
896 		"ring_index %d", nxgep->max_tdcs, ring_index));
897 
898 	switch (nxge_tx_scheme) {
899 	case NXGE_USE_START:
900 		if (nxge_start(nxgep, tx_rings[ring_index], mp)) {
901 			NXGE_DEBUG_MSG((nxgep, TX_CTL, "<== nxge_send: failed "
902 				"ring index %d", ring_index));
903 			return (B_FALSE);
904 		}
905 		break;
906 
907 	case NXGE_USE_SERIAL:
908 	default:
909 		tx_ring_p = tx_rings[ring_index];
910 		nxge_serialize_enter(tx_ring_p->serial, mp);
911 		break;
912 	}
913 
914 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "<== nxge_send: ring index %d",
915 		ring_index));
916 
917 	return (B_TRUE);
918 }
919 
920 /*
921  * nxge_m_tx() - send a chain of packets
922  */
923 mblk_t *
924 nxge_m_tx(void *arg, mblk_t *mp)
925 {
926 	p_nxge_t 		nxgep = (p_nxge_t)arg;
927 	mblk_t 			*next;
928 	mac_tx_hint_t		hint;
929 
930 	if (!(nxgep->drv_state & STATE_HW_INITIALIZED)) {
931 		NXGE_DEBUG_MSG((nxgep, DDI_CTL,
932 			"==> nxge_m_tx: hardware not initialized"));
933 		NXGE_DEBUG_MSG((nxgep, DDI_CTL,
934 			"<== nxge_m_tx"));
935 		return (mp);
936 	}
937 
938 	hint.hash =  NULL;
939 	hint.vid =  0;
940 	hint.sap =  0;
941 
942 	while (mp != NULL) {
943 		next = mp->b_next;
944 		mp->b_next = NULL;
945 
946 		/*
947 		 * Until Nemo tx resource works, the mac driver
948 		 * does the load balancing based on TCP port,
949 		 * or CPU. For debugging, we use a system
950 		 * configurable parameter.
951 		 */
952 		if (!nxge_send(nxgep, mp, &hint)) {
953 			mp->b_next = next;
954 			break;
955 		}
956 
957 		mp = next;
958 	}
959 
960 	return (mp);
961 }
962 
963 int
964 nxge_tx_lb_ring_1(p_mblk_t mp, uint32_t maxtdcs, p_mac_tx_hint_t hp)
965 {
966 	uint8_t 		ring_index = 0;
967 	uint8_t 		*tcp_port;
968 	p_mblk_t 		nmp;
969 	size_t 			mblk_len;
970 	size_t 			iph_len;
971 	size_t 			hdrs_size;
972 	uint8_t			hdrs_buf[sizeof (struct  ether_header) +
973 					IP_MAX_HDR_LENGTH + sizeof (uint32_t)];
974 				/*
975 				 * allocate space big enough to cover
976 				 * the max ip header length and the first
977 				 * 4 bytes of the TCP/IP header.
978 				 */
979 
980 	boolean_t		qos = B_FALSE;
981 
982 	NXGE_DEBUG_MSG((NULL, TX_CTL, "==> nxge_tx_lb_ring"));
983 
984 	if (hp->vid) {
985 		qos = B_TRUE;
986 	}
987 	switch (nxge_tx_lb_policy) {
988 	case NXGE_TX_LB_TCPUDP: /* default IPv4 TCP/UDP */
989 	default:
990 		tcp_port = mp->b_rptr;
991 		if (!nxge_no_tx_lb && !qos &&
992 			(ntohs(((p_ether_header_t)tcp_port)->ether_type)
993 				== ETHERTYPE_IP)) {
994 			nmp = mp;
995 			mblk_len = MBLKL(nmp);
996 			tcp_port = NULL;
997 			if (mblk_len > sizeof (struct ether_header) +
998 					sizeof (uint8_t)) {
999 				tcp_port = nmp->b_rptr +
1000 					sizeof (struct ether_header);
1001 				mblk_len -= sizeof (struct ether_header);
1002 				iph_len = ((*tcp_port) & 0x0f) << 2;
1003 				if (mblk_len > (iph_len + sizeof (uint32_t))) {
1004 					tcp_port = nmp->b_rptr;
1005 				} else {
1006 					tcp_port = NULL;
1007 				}
1008 			}
1009 			if (tcp_port == NULL) {
1010 				hdrs_size = 0;
1011 				((p_ether_header_t)hdrs_buf)->ether_type = 0;
1012 				while ((nmp) && (hdrs_size <
1013 						sizeof (hdrs_buf))) {
1014 					mblk_len = MBLKL(nmp);
1015 					if (mblk_len >=
1016 						(sizeof (hdrs_buf) - hdrs_size))
1017 						mblk_len = sizeof (hdrs_buf) -
1018 							hdrs_size;
1019 					bcopy(nmp->b_rptr,
1020 						&hdrs_buf[hdrs_size], mblk_len);
1021 					hdrs_size += mblk_len;
1022 					nmp = nmp->b_cont;
1023 				}
1024 				tcp_port = hdrs_buf;
1025 			}
1026 			tcp_port += sizeof (ether_header_t);
1027 			if (!(tcp_port[6] & 0x3f) && !(tcp_port[7] & 0xff)) {
1028 				switch (tcp_port[9]) {
1029 				case IPPROTO_TCP:
1030 				case IPPROTO_UDP:
1031 				case IPPROTO_ESP:
1032 					tcp_port += ((*tcp_port) & 0x0f) << 2;
1033 					ring_index =
1034 					    ((tcp_port[0] ^
1035 					    tcp_port[1] ^
1036 					    tcp_port[2] ^
1037 					    tcp_port[3]) % maxtdcs);
1038 					break;
1039 
1040 				case IPPROTO_AH:
1041 					/* SPI starts at the 4th byte */
1042 					tcp_port += ((*tcp_port) & 0x0f) << 2;
1043 					ring_index =
1044 					    ((tcp_port[4] ^
1045 					    tcp_port[5] ^
1046 					    tcp_port[6] ^
1047 					    tcp_port[7]) % maxtdcs);
1048 					break;
1049 
1050 				default:
1051 					ring_index = tcp_port[19] % maxtdcs;
1052 					break;
1053 				}
1054 			} else { /* fragmented packet */
1055 				ring_index = tcp_port[19] % maxtdcs;
1056 			}
1057 		} else {
1058 			ring_index = mp->b_band % maxtdcs;
1059 		}
1060 		break;
1061 
1062 	case NXGE_TX_LB_HASH:
1063 		if (hp->hash) {
1064 #if defined(__i386)
1065 			ring_index = ((uint32_t)(hp->hash) % maxtdcs);
1066 #else
1067 			ring_index = ((uint64_t)(hp->hash) % maxtdcs);
1068 #endif
1069 		} else {
1070 			ring_index = mp->b_band % maxtdcs;
1071 		}
1072 		break;
1073 
1074 	case NXGE_TX_LB_DEST_MAC: /* Use destination MAC address */
1075 		tcp_port = mp->b_rptr;
1076 		ring_index = tcp_port[5] % maxtdcs;
1077 		break;
1078 	}
1079 
1080 	NXGE_DEBUG_MSG((NULL, TX_CTL, "<== nxge_tx_lb_ring"));
1081 
1082 	return (ring_index);
1083 }
1084 
1085 uint_t
1086 nxge_reschedule(caddr_t arg)
1087 {
1088 	p_nxge_t nxgep;
1089 
1090 	nxgep = (p_nxge_t)arg;
1091 
1092 	NXGE_DEBUG_MSG((nxgep, TX_CTL, "==> nxge_reschedule"));
1093 
1094 	if (nxgep->nxge_mac_state == NXGE_MAC_STARTED &&
1095 			nxgep->resched_needed) {
1096 		mac_tx_update(nxgep->mach);
1097 		nxgep->resched_needed = B_FALSE;
1098 		nxgep->resched_running = B_FALSE;
1099 	}
1100 
1101 	NXGE_DEBUG_MSG((NULL, TX_CTL, "<== nxge_reschedule"));
1102 	return (DDI_INTR_CLAIMED);
1103 }
1104