xref: /freebsd/sys/dev/igc/igc_txrx.c (revision f7926a6d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2016 Matthew Macy <mmacy@mattmacy.io>
5  * All rights reserved.
6  * Copyright (c) 2021 Rubicon Communications, LLC (Netgate)
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include "if_igc.h"
34 
35 #ifdef RSS
36 #include <net/rss_config.h>
37 #include <netinet/in_rss.h>
38 #endif
39 
40 #ifdef VERBOSE_DEBUG
41 #define DPRINTF device_printf
42 #else
43 #define DPRINTF(...)
44 #endif
45 
46 /*********************************************************************
47  *  Local Function prototypes
48  *********************************************************************/
49 static int igc_isc_txd_encap(void *arg, if_pkt_info_t pi);
50 static void igc_isc_txd_flush(void *arg, uint16_t txqid, qidx_t pidx);
51 static int igc_isc_txd_credits_update(void *arg, uint16_t txqid, bool clear);
52 
53 static void igc_isc_rxd_refill(void *arg, if_rxd_update_t iru);
54 
55 static void igc_isc_rxd_flush(void *arg, uint16_t rxqid, uint8_t flid __unused,
56     qidx_t pidx);
57 static int igc_isc_rxd_available(void *arg, uint16_t rxqid, qidx_t idx,
58     qidx_t budget);
59 
60 static int igc_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri);
61 
62 static int igc_tx_ctx_setup(struct tx_ring *txr, if_pkt_info_t pi,
63     uint32_t *cmd_type_len, uint32_t *olinfo_status);
64 static int igc_tso_setup(struct tx_ring *txr, if_pkt_info_t pi,
65     uint32_t *cmd_type_len, uint32_t *olinfo_status);
66 
67 static void igc_rx_checksum(uint32_t staterr, if_rxd_info_t ri, uint32_t ptype);
68 static int igc_determine_rsstype(uint16_t pkt_info);
69 
70 extern void igc_if_enable_intr(if_ctx_t ctx);
71 extern int igc_intr(void *arg);
72 
73 struct if_txrx igc_txrx = {
74 	.ift_txd_encap = igc_isc_txd_encap,
75 	.ift_txd_flush = igc_isc_txd_flush,
76 	.ift_txd_credits_update = igc_isc_txd_credits_update,
77 	.ift_rxd_available = igc_isc_rxd_available,
78 	.ift_rxd_pkt_get = igc_isc_rxd_pkt_get,
79 	.ift_rxd_refill = igc_isc_rxd_refill,
80 	.ift_rxd_flush = igc_isc_rxd_flush,
81 	.ift_legacy_intr = igc_intr
82 };
83 
84 void
85 igc_dump_rs(struct igc_adapter *adapter)
86 {
87 	if_softc_ctx_t scctx = adapter->shared;
88 	struct igc_tx_queue *que;
89 	struct tx_ring *txr;
90 	qidx_t i, ntxd, qid, cur;
91 	int16_t rs_cidx;
92 	uint8_t status;
93 
94 	printf("\n");
95 	ntxd = scctx->isc_ntxd[0];
96 	for (qid = 0; qid < adapter->tx_num_queues; qid++) {
97 		que = &adapter->tx_queues[qid];
98 		txr =  &que->txr;
99 		rs_cidx = txr->tx_rs_cidx;
100 		if (rs_cidx != txr->tx_rs_pidx) {
101 			cur = txr->tx_rsq[rs_cidx];
102 			status = txr->tx_base[cur].upper.fields.status;
103 			if (!(status & IGC_TXD_STAT_DD))
104 				printf("qid[%d]->tx_rsq[%d]: %d clear ", qid, rs_cidx, cur);
105 		} else {
106 			rs_cidx = (rs_cidx-1)&(ntxd-1);
107 			cur = txr->tx_rsq[rs_cidx];
108 			printf("qid[%d]->tx_rsq[rs_cidx-1=%d]: %d  ", qid, rs_cidx, cur);
109 		}
110 		printf("cidx_prev=%d rs_pidx=%d ",txr->tx_cidx_processed, txr->tx_rs_pidx);
111 		for (i = 0; i < ntxd; i++) {
112 			if (txr->tx_base[i].upper.fields.status & IGC_TXD_STAT_DD)
113 				printf("%d set ", i);
114 		}
115 		printf("\n");
116 	}
117 }
118 
119 /**********************************************************************
120  *
121  *  Setup work for hardware segmentation offload (TSO) on
122  *  adapters using advanced tx descriptors
123  *
124  **********************************************************************/
125 static int
126 igc_tso_setup(struct tx_ring *txr, if_pkt_info_t pi, uint32_t *cmd_type_len,
127     uint32_t *olinfo_status)
128 {
129 	struct igc_adv_tx_context_desc *TXD;
130 	uint32_t type_tucmd_mlhl = 0, vlan_macip_lens = 0;
131 	uint32_t mss_l4len_idx = 0;
132 	uint32_t paylen;
133 
134 	switch(pi->ipi_etype) {
135 	case ETHERTYPE_IPV6:
136 		type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_IPV6;
137 		break;
138 	case ETHERTYPE_IP:
139 		type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_IPV4;
140 		/* Tell transmit desc to also do IPv4 checksum. */
141 		*olinfo_status |= IGC_TXD_POPTS_IXSM << 8;
142 		break;
143 	default:
144 		panic("%s: CSUM_TSO but no supported IP version (0x%04x)",
145 		      __func__, ntohs(pi->ipi_etype));
146 		break;
147 	}
148 
149 	TXD = (struct igc_adv_tx_context_desc *) &txr->tx_base[pi->ipi_pidx];
150 
151 	/* This is used in the transmit desc in encap */
152 	paylen = pi->ipi_len - pi->ipi_ehdrlen - pi->ipi_ip_hlen - pi->ipi_tcp_hlen;
153 
154 	/* VLAN MACLEN IPLEN */
155 	if (pi->ipi_mflags & M_VLANTAG) {
156 		vlan_macip_lens |= (pi->ipi_vtag << IGC_ADVTXD_VLAN_SHIFT);
157 	}
158 
159 	vlan_macip_lens |= pi->ipi_ehdrlen << IGC_ADVTXD_MACLEN_SHIFT;
160 	vlan_macip_lens |= pi->ipi_ip_hlen;
161 	TXD->vlan_macip_lens = htole32(vlan_macip_lens);
162 
163 	/* ADV DTYPE TUCMD */
164 	type_tucmd_mlhl |= IGC_ADVTXD_DCMD_DEXT | IGC_ADVTXD_DTYP_CTXT;
165 	type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_L4T_TCP;
166 	TXD->type_tucmd_mlhl = htole32(type_tucmd_mlhl);
167 
168 	/* MSS L4LEN IDX */
169 	mss_l4len_idx |= (pi->ipi_tso_segsz << IGC_ADVTXD_MSS_SHIFT);
170 	mss_l4len_idx |= (pi->ipi_tcp_hlen << IGC_ADVTXD_L4LEN_SHIFT);
171 	TXD->mss_l4len_idx = htole32(mss_l4len_idx);
172 
173 	TXD->seqnum_seed = htole32(0);
174 	*cmd_type_len |= IGC_ADVTXD_DCMD_TSE;
175 	*olinfo_status |= IGC_TXD_POPTS_TXSM << 8;
176 	*olinfo_status |= paylen << IGC_ADVTXD_PAYLEN_SHIFT;
177 
178 	return (1);
179 }
180 
181 /*********************************************************************
182  *
183  *  Advanced Context Descriptor setup for VLAN, CSUM or TSO
184  *
185  **********************************************************************/
186 static int
187 igc_tx_ctx_setup(struct tx_ring *txr, if_pkt_info_t pi, uint32_t *cmd_type_len,
188     uint32_t *olinfo_status)
189 {
190 	struct igc_adv_tx_context_desc *TXD;
191 	uint32_t vlan_macip_lens, type_tucmd_mlhl;
192 	uint32_t mss_l4len_idx;
193 	mss_l4len_idx = vlan_macip_lens = type_tucmd_mlhl = 0;
194 
195 	/* First check if TSO is to be used */
196 	if (pi->ipi_csum_flags & CSUM_TSO)
197 		return (igc_tso_setup(txr, pi, cmd_type_len, olinfo_status));
198 
199 	/* Indicate the whole packet as payload when not doing TSO */
200 	*olinfo_status |= pi->ipi_len << IGC_ADVTXD_PAYLEN_SHIFT;
201 
202 	/* Now ready a context descriptor */
203 	TXD = (struct igc_adv_tx_context_desc *) &txr->tx_base[pi->ipi_pidx];
204 
205 	/*
206 	** In advanced descriptors the vlan tag must
207 	** be placed into the context descriptor. Hence
208 	** we need to make one even if not doing offloads.
209 	*/
210 	if (pi->ipi_mflags & M_VLANTAG) {
211 		vlan_macip_lens |= (pi->ipi_vtag << IGC_ADVTXD_VLAN_SHIFT);
212 	} else if ((pi->ipi_csum_flags & IGC_CSUM_OFFLOAD) == 0) {
213 		return (0);
214 	}
215 
216 	/* Set the ether header length */
217 	vlan_macip_lens |= pi->ipi_ehdrlen << IGC_ADVTXD_MACLEN_SHIFT;
218 
219 	switch(pi->ipi_etype) {
220 	case ETHERTYPE_IP:
221 		type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_IPV4;
222 		break;
223 	case ETHERTYPE_IPV6:
224 		type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_IPV6;
225 		break;
226 	default:
227 		break;
228 	}
229 
230 	vlan_macip_lens |= pi->ipi_ip_hlen;
231 	type_tucmd_mlhl |= IGC_ADVTXD_DCMD_DEXT | IGC_ADVTXD_DTYP_CTXT;
232 
233 	switch (pi->ipi_ipproto) {
234 	case IPPROTO_TCP:
235 		if (pi->ipi_csum_flags & (CSUM_IP_TCP | CSUM_IP6_TCP)) {
236 			type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_L4T_TCP;
237 			*olinfo_status |= IGC_TXD_POPTS_TXSM << 8;
238 		}
239 		break;
240 	case IPPROTO_UDP:
241 		if (pi->ipi_csum_flags & (CSUM_IP_UDP | CSUM_IP6_UDP)) {
242 			type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_L4T_UDP;
243 			*olinfo_status |= IGC_TXD_POPTS_TXSM << 8;
244 		}
245 		break;
246 	case IPPROTO_SCTP:
247 		if (pi->ipi_csum_flags & (CSUM_IP_SCTP | CSUM_IP6_SCTP)) {
248 			type_tucmd_mlhl |= IGC_ADVTXD_TUCMD_L4T_SCTP;
249 			*olinfo_status |= IGC_TXD_POPTS_TXSM << 8;
250 		}
251 		break;
252 	default:
253 		break;
254 	}
255 
256 	/* Now copy bits into descriptor */
257 	TXD->vlan_macip_lens = htole32(vlan_macip_lens);
258 	TXD->type_tucmd_mlhl = htole32(type_tucmd_mlhl);
259 	TXD->seqnum_seed = htole32(0);
260 	TXD->mss_l4len_idx = htole32(mss_l4len_idx);
261 
262 	return (1);
263 }
264 
265 static int
266 igc_isc_txd_encap(void *arg, if_pkt_info_t pi)
267 {
268 	struct igc_adapter *sc = arg;
269 	if_softc_ctx_t scctx = sc->shared;
270 	struct igc_tx_queue *que = &sc->tx_queues[pi->ipi_qsidx];
271 	struct tx_ring *txr = &que->txr;
272 	int nsegs = pi->ipi_nsegs;
273 	bus_dma_segment_t *segs = pi->ipi_segs;
274 	union igc_adv_tx_desc *txd = NULL;
275 	int i, j, pidx_last;
276 	uint32_t olinfo_status, cmd_type_len, txd_flags;
277 	qidx_t ntxd;
278 
279 	pidx_last = olinfo_status = 0;
280 	/* Basic descriptor defines */
281 	cmd_type_len = (IGC_ADVTXD_DTYP_DATA |
282 			IGC_ADVTXD_DCMD_IFCS | IGC_ADVTXD_DCMD_DEXT);
283 
284 	if (pi->ipi_mflags & M_VLANTAG)
285 		cmd_type_len |= IGC_ADVTXD_DCMD_VLE;
286 
287 	i = pi->ipi_pidx;
288 	ntxd = scctx->isc_ntxd[0];
289 	txd_flags = pi->ipi_flags & IPI_TX_INTR ? IGC_ADVTXD_DCMD_RS : 0;
290 	/* Consume the first descriptor */
291 	i += igc_tx_ctx_setup(txr, pi, &cmd_type_len, &olinfo_status);
292 	if (i == scctx->isc_ntxd[0])
293 		i = 0;
294 
295 	for (j = 0; j < nsegs; j++) {
296 		bus_size_t seglen;
297 		bus_addr_t segaddr;
298 
299 		txd = (union igc_adv_tx_desc *)&txr->tx_base[i];
300 		seglen = segs[j].ds_len;
301 		segaddr = htole64(segs[j].ds_addr);
302 
303 		txd->read.buffer_addr = segaddr;
304 		txd->read.cmd_type_len = htole32(IGC_ADVTXD_DCMD_IFCS |
305 		    cmd_type_len | seglen);
306 		txd->read.olinfo_status = htole32(olinfo_status);
307 		pidx_last = i;
308 		if (++i == scctx->isc_ntxd[0]) {
309 			i = 0;
310 		}
311 	}
312 	if (txd_flags) {
313 		txr->tx_rsq[txr->tx_rs_pidx] = pidx_last;
314 		txr->tx_rs_pidx = (txr->tx_rs_pidx+1) & (ntxd-1);
315 		MPASS(txr->tx_rs_pidx != txr->tx_rs_cidx);
316 	}
317 
318 	txd->read.cmd_type_len |= htole32(IGC_ADVTXD_DCMD_EOP | txd_flags);
319 	pi->ipi_new_pidx = i;
320 
321 	return (0);
322 }
323 
324 static void
325 igc_isc_txd_flush(void *arg, uint16_t txqid, qidx_t pidx)
326 {
327 	struct igc_adapter *adapter	= arg;
328 	struct igc_tx_queue *que	= &adapter->tx_queues[txqid];
329 	struct tx_ring *txr	= &que->txr;
330 
331 	IGC_WRITE_REG(&adapter->hw, IGC_TDT(txr->me), pidx);
332 }
333 
334 static int
335 igc_isc_txd_credits_update(void *arg, uint16_t txqid, bool clear)
336 {
337 	struct igc_adapter *adapter = arg;
338 	if_softc_ctx_t scctx = adapter->shared;
339 	struct igc_tx_queue *que = &adapter->tx_queues[txqid];
340 	struct tx_ring *txr = &que->txr;
341 
342 	qidx_t processed = 0;
343 	int updated;
344 	qidx_t cur, prev, ntxd, rs_cidx;
345 	int32_t delta;
346 	uint8_t status;
347 
348 	rs_cidx = txr->tx_rs_cidx;
349 	if (rs_cidx == txr->tx_rs_pidx)
350 		return (0);
351 	cur = txr->tx_rsq[rs_cidx];
352 	status = ((union igc_adv_tx_desc *)&txr->tx_base[cur])->wb.status;
353 	updated = !!(status & IGC_TXD_STAT_DD);
354 
355 	if (!updated)
356 		return (0);
357 
358 	/* If clear is false just let caller know that there
359 	 * are descriptors to reclaim */
360 	if (!clear)
361 		return (1);
362 
363 	prev = txr->tx_cidx_processed;
364 	ntxd = scctx->isc_ntxd[0];
365 	do {
366 		MPASS(prev != cur);
367 		delta = (int32_t)cur - (int32_t)prev;
368 		if (delta < 0)
369 			delta += ntxd;
370 		MPASS(delta > 0);
371 
372 		processed += delta;
373 		prev  = cur;
374 		rs_cidx = (rs_cidx + 1) & (ntxd-1);
375 		if (rs_cidx  == txr->tx_rs_pidx)
376 			break;
377 		cur = txr->tx_rsq[rs_cidx];
378 		status = ((union igc_adv_tx_desc *)&txr->tx_base[cur])->wb.status;
379 	} while ((status & IGC_TXD_STAT_DD));
380 
381 	txr->tx_rs_cidx = rs_cidx;
382 	txr->tx_cidx_processed = prev;
383 	return (processed);
384 }
385 
386 static void
387 igc_isc_rxd_refill(void *arg, if_rxd_update_t iru)
388 {
389 	struct igc_adapter *sc = arg;
390 	if_softc_ctx_t scctx = sc->shared;
391 	uint16_t rxqid = iru->iru_qsidx;
392 	struct igc_rx_queue *que = &sc->rx_queues[rxqid];
393 	union igc_adv_rx_desc *rxd;
394 	struct rx_ring *rxr = &que->rxr;
395 	uint64_t *paddrs;
396 	uint32_t next_pidx, pidx;
397 	uint16_t count;
398 	int i;
399 
400 	paddrs = iru->iru_paddrs;
401 	pidx = iru->iru_pidx;
402 	count = iru->iru_count;
403 
404 	for (i = 0, next_pidx = pidx; i < count; i++) {
405 		rxd = (union igc_adv_rx_desc *)&rxr->rx_base[next_pidx];
406 
407 		rxd->read.pkt_addr = htole64(paddrs[i]);
408 		if (++next_pidx == scctx->isc_nrxd[0])
409 			next_pidx = 0;
410 	}
411 }
412 
413 static void
414 igc_isc_rxd_flush(void *arg, uint16_t rxqid, uint8_t flid __unused, qidx_t pidx)
415 {
416 	struct igc_adapter *sc = arg;
417 	struct igc_rx_queue *que = &sc->rx_queues[rxqid];
418 	struct rx_ring *rxr = &que->rxr;
419 
420 	IGC_WRITE_REG(&sc->hw, IGC_RDT(rxr->me), pidx);
421 }
422 
423 static int
424 igc_isc_rxd_available(void *arg, uint16_t rxqid, qidx_t idx, qidx_t budget)
425 {
426 	struct igc_adapter *sc = arg;
427 	if_softc_ctx_t scctx = sc->shared;
428 	struct igc_rx_queue *que = &sc->rx_queues[rxqid];
429 	struct rx_ring *rxr = &que->rxr;
430 	union igc_adv_rx_desc *rxd;
431 	uint32_t staterr = 0;
432 	int cnt, i;
433 
434 	for (cnt = 0, i = idx; cnt < scctx->isc_nrxd[0] && cnt <= budget;) {
435 		rxd = (union igc_adv_rx_desc *)&rxr->rx_base[i];
436 		staterr = le32toh(rxd->wb.upper.status_error);
437 
438 		if ((staterr & IGC_RXD_STAT_DD) == 0)
439 			break;
440 		if (++i == scctx->isc_nrxd[0])
441 			i = 0;
442 		if (staterr & IGC_RXD_STAT_EOP)
443 			cnt++;
444 	}
445 	return (cnt);
446 }
447 
448 /****************************************************************
449  * Routine sends data which has been dma'ed into host memory
450  * to upper layer. Initialize ri structure.
451  *
452  * Returns 0 upon success, errno on failure
453  ***************************************************************/
454 
455 static int
456 igc_isc_rxd_pkt_get(void *arg, if_rxd_info_t ri)
457 {
458 	struct igc_adapter *adapter = arg;
459 	if_softc_ctx_t scctx = adapter->shared;
460 	struct igc_rx_queue *que = &adapter->rx_queues[ri->iri_qsidx];
461 	struct rx_ring *rxr = &que->rxr;
462 	union igc_adv_rx_desc *rxd;
463 
464 	uint16_t pkt_info, len;
465 	uint32_t ptype, staterr;
466 	int i, cidx;
467 	bool eop;
468 
469 	staterr = i = 0;
470 	cidx = ri->iri_cidx;
471 
472 	do {
473 		rxd = (union igc_adv_rx_desc *)&rxr->rx_base[cidx];
474 		staterr = le32toh(rxd->wb.upper.status_error);
475 		pkt_info = le16toh(rxd->wb.lower.lo_dword.hs_rss.pkt_info);
476 
477 		MPASS ((staterr & IGC_RXD_STAT_DD) != 0);
478 
479 		len = le16toh(rxd->wb.upper.length);
480 		ptype = le32toh(rxd->wb.lower.lo_dword.data) &  IGC_PKTTYPE_MASK;
481 
482 		ri->iri_len += len;
483 		rxr->rx_bytes += ri->iri_len;
484 
485 		rxd->wb.upper.status_error = 0;
486 		eop = ((staterr & IGC_RXD_STAT_EOP) == IGC_RXD_STAT_EOP);
487 
488 		/* Make sure bad packets are discarded */
489 		if (eop && ((staterr & IGC_RXDEXT_STATERR_RXE) != 0)) {
490 			adapter->dropped_pkts++;
491 			++rxr->rx_discarded;
492 			return (EBADMSG);
493 		}
494 		ri->iri_frags[i].irf_flid = 0;
495 		ri->iri_frags[i].irf_idx = cidx;
496 		ri->iri_frags[i].irf_len = len;
497 
498 		if (++cidx == scctx->isc_nrxd[0])
499 			cidx = 0;
500 #ifdef notyet
501 		if (rxr->hdr_split == true) {
502 			ri->iri_frags[i].irf_flid = 1;
503 			ri->iri_frags[i].irf_idx = cidx;
504 			if (++cidx == scctx->isc_nrxd[0])
505 				cidx = 0;
506 		}
507 #endif
508 		i++;
509 	} while (!eop);
510 
511 	rxr->rx_packets++;
512 
513 	if ((scctx->isc_capenable & IFCAP_RXCSUM) != 0)
514 		igc_rx_checksum(staterr, ri, ptype);
515 
516 	if ((scctx->isc_capenable & IFCAP_VLAN_HWTAGGING) != 0 &&
517 	    (staterr & IGC_RXD_STAT_VP) != 0) {
518 		ri->iri_vtag = le16toh(rxd->wb.upper.vlan);
519 		ri->iri_flags |= M_VLANTAG;
520 	}
521 
522 	ri->iri_flowid =
523 		le32toh(rxd->wb.lower.hi_dword.rss);
524 	ri->iri_rsstype = igc_determine_rsstype(pkt_info);
525 	ri->iri_nfrags = i;
526 
527 	return (0);
528 }
529 
530 /*********************************************************************
531  *
532  *  Verify that the hardware indicated that the checksum is valid.
533  *  Inform the stack about the status of checksum so that stack
534  *  doesn't spend time verifying the checksum.
535  *
536  *********************************************************************/
537 static void
538 igc_rx_checksum(uint32_t staterr, if_rxd_info_t ri, uint32_t ptype)
539 {
540 	uint16_t status = (uint16_t)staterr;
541 	uint8_t errors = (uint8_t)(staterr >> 24);
542 
543 	if (__predict_false(status & IGC_RXD_STAT_IXSM))
544 		return;
545 
546 	/* If there is a layer 3 or 4 error we are done */
547 	if (__predict_false(errors & (IGC_RXD_ERR_IPE | IGC_RXD_ERR_TCPE)))
548 		return;
549 
550 	/* IP Checksum Good */
551 	if (status & IGC_RXD_STAT_IPCS)
552 		ri->iri_csum_flags = (CSUM_IP_CHECKED | CSUM_IP_VALID);
553 
554 	/* Valid L4E checksum */
555 	if (__predict_true(status &
556 	    (IGC_RXD_STAT_TCPCS | IGC_RXD_STAT_UDPCS))) {
557 		/* SCTP header present */
558 		if (__predict_false((ptype & IGC_RXDADV_PKTTYPE_ETQF) == 0 &&
559 		    (ptype & IGC_RXDADV_PKTTYPE_SCTP) != 0)) {
560 			ri->iri_csum_flags |= CSUM_SCTP_VALID;
561 		} else {
562 			ri->iri_csum_flags |= CSUM_DATA_VALID | CSUM_PSEUDO_HDR;
563 			ri->iri_csum_data = htons(0xffff);
564 		}
565 	}
566 }
567 
568 /********************************************************************
569  *
570  *  Parse the packet type to determine the appropriate hash
571  *
572  ******************************************************************/
573 static int
574 igc_determine_rsstype(uint16_t pkt_info)
575 {
576 	switch (pkt_info & IGC_RXDADV_RSSTYPE_MASK) {
577 	case IGC_RXDADV_RSSTYPE_IPV4_TCP:
578 		return M_HASHTYPE_RSS_TCP_IPV4;
579 	case IGC_RXDADV_RSSTYPE_IPV4:
580 		return M_HASHTYPE_RSS_IPV4;
581 	case IGC_RXDADV_RSSTYPE_IPV6_TCP:
582 		return M_HASHTYPE_RSS_TCP_IPV6;
583 	case IGC_RXDADV_RSSTYPE_IPV6_EX:
584 		return M_HASHTYPE_RSS_IPV6_EX;
585 	case IGC_RXDADV_RSSTYPE_IPV6:
586 		return M_HASHTYPE_RSS_IPV6;
587 	case IGC_RXDADV_RSSTYPE_IPV6_TCP_EX:
588 		return M_HASHTYPE_RSS_TCP_IPV6_EX;
589 	default:
590 		return M_HASHTYPE_OPAQUE;
591 	}
592 }
593