xref: /freebsd/sys/dev/cxgbe/t4_netmap.c (revision 95d32ad641bd9d430e9eaeb0ac284acd81c17341)
1 /*-
2  * Copyright (c) 2014 Chelsio Communications, Inc.
3  * All rights reserved.
4  * Written by: Navdeep Parhar <np@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include "opt_inet.h"
32 #include "opt_inet6.h"
33 
34 #ifdef DEV_NETMAP
35 #include <sys/param.h>
36 #include <sys/bus.h>
37 #include <sys/eventhandler.h>
38 #include <sys/lock.h>
39 #include <sys/mbuf.h>
40 #include <sys/module.h>
41 #include <sys/selinfo.h>
42 #include <sys/socket.h>
43 #include <sys/sockio.h>
44 #include <machine/bus.h>
45 #include <net/ethernet.h>
46 #include <net/if.h>
47 #include <net/if_media.h>
48 #include <net/if_var.h>
49 #include <net/if_clone.h>
50 #include <net/if_types.h>
51 #include <net/netmap.h>
52 #include <dev/netmap/netmap_kern.h>
53 
54 #include "common/common.h"
55 #include "common/t4_regs.h"
56 #include "common/t4_regs_values.h"
57 
58 extern int fl_pad;	/* XXXNM */
59 
60 /*
61  * 0 = normal netmap rx
62  * 1 = black hole
63  * 2 = supermassive black hole (buffer packing enabled)
64  */
65 int black_hole = 0;
66 SYSCTL_INT(_hw_cxgbe, OID_AUTO, nm_black_hole, CTLFLAG_RWTUN, &black_hole, 0,
67     "Sink incoming packets.");
68 
69 int rx_ndesc = 256;
70 SYSCTL_INT(_hw_cxgbe, OID_AUTO, nm_rx_ndesc, CTLFLAG_RWTUN,
71     &rx_ndesc, 0, "# of rx descriptors after which the hw cidx is updated.");
72 
73 int rx_nframes = 64;
74 SYSCTL_INT(_hw_cxgbe, OID_AUTO, nm_rx_nframes, CTLFLAG_RWTUN,
75     &rx_nframes, 0, "max # of frames received before waking up netmap rx.");
76 
77 int holdoff_tmr_idx = 2;
78 SYSCTL_INT(_hw_cxgbe, OID_AUTO, nm_holdoff_tmr_idx, CTLFLAG_RWTUN,
79     &holdoff_tmr_idx, 0, "Holdoff timer index for netmap rx queues.");
80 
81 /*
82  * Congestion drops.
83  * -1: no congestion feedback (not recommended).
84  *  0: backpressure the channel instead of dropping packets right away.
85  *  1: no backpressure, drop packets for the congested queue immediately.
86  */
87 static int nm_cong_drop = 1;
88 SYSCTL_INT(_hw_cxgbe, OID_AUTO, nm_cong_drop, CTLFLAG_RWTUN,
89     &nm_cong_drop, 0,
90     "Congestion control for netmap rx queues (0 = backpressure, 1 = drop");
91 
92 int starve_fl = 0;
93 SYSCTL_INT(_hw_cxgbe, OID_AUTO, starve_fl, CTLFLAG_RWTUN,
94     &starve_fl, 0, "Don't ring fl db for netmap rx queues.");
95 
96 /*
97  * Try to process tx credits in bulk.  This may cause a delay in the return of
98  * tx credits and is suitable for bursty or non-stop tx only.
99  */
100 int lazy_tx_credit_flush = 1;
101 SYSCTL_INT(_hw_cxgbe, OID_AUTO, lazy_tx_credit_flush, CTLFLAG_RWTUN,
102     &lazy_tx_credit_flush, 0, "lazy credit flush for netmap tx queues.");
103 
104 /*
105  * Split the netmap rx queues into two groups that populate separate halves of
106  * the RSS indirection table.  This allows filters with hashmask to steer to a
107  * particular group of queues.
108  */
109 static int nm_split_rss = 0;
110 SYSCTL_INT(_hw_cxgbe, OID_AUTO, nm_split_rss, CTLFLAG_RWTUN,
111     &nm_split_rss, 0, "Split the netmap rx queues into two groups.");
112 
113 /*
114  * netmap(4) says "netmap does not use features such as checksum offloading, TCP
115  * segmentation offloading, encryption, VLAN encapsulation/decapsulation, etc."
116  * but this knob can be used to get the hardware to checksum all tx traffic
117  * anyway.
118  */
119 static int nm_txcsum = 0;
120 SYSCTL_INT(_hw_cxgbe, OID_AUTO, nm_txcsum, CTLFLAG_RWTUN,
121     &nm_txcsum, 0, "Enable transmit checksum offloading.");
122 
123 static int
124 alloc_nm_rxq_hwq(struct vi_info *vi, struct sge_nm_rxq *nm_rxq, int cong)
125 {
126 	int rc, cntxt_id, i;
127 	__be32 v;
128 	struct adapter *sc = vi->pi->adapter;
129 	struct sge_params *sp = &sc->params.sge;
130 	struct netmap_adapter *na = NA(vi->ifp);
131 	struct fw_iq_cmd c;
132 
133 	MPASS(na != NULL);
134 	MPASS(nm_rxq->iq_desc != NULL);
135 	MPASS(nm_rxq->fl_desc != NULL);
136 
137 	bzero(nm_rxq->iq_desc, vi->qsize_rxq * IQ_ESIZE);
138 	bzero(nm_rxq->fl_desc, na->num_rx_desc * EQ_ESIZE + sp->spg_len);
139 
140 	bzero(&c, sizeof(c));
141 	c.op_to_vfn = htobe32(V_FW_CMD_OP(FW_IQ_CMD) | F_FW_CMD_REQUEST |
142 	    F_FW_CMD_WRITE | F_FW_CMD_EXEC | V_FW_IQ_CMD_PFN(sc->pf) |
143 	    V_FW_IQ_CMD_VFN(0));
144 	c.alloc_to_len16 = htobe32(F_FW_IQ_CMD_ALLOC | F_FW_IQ_CMD_IQSTART |
145 	    FW_LEN16(c));
146 	MPASS(!forwarding_intr_to_fwq(sc));
147 	KASSERT(nm_rxq->intr_idx < sc->intr_count,
148 	    ("%s: invalid direct intr_idx %d", __func__, nm_rxq->intr_idx));
149 	v = V_FW_IQ_CMD_IQANDSTINDEX(nm_rxq->intr_idx);
150 	c.type_to_iqandstindex = htobe32(v |
151 	    V_FW_IQ_CMD_TYPE(FW_IQ_TYPE_FL_INT_CAP) |
152 	    V_FW_IQ_CMD_VIID(vi->viid) |
153 	    V_FW_IQ_CMD_IQANUD(X_UPDATEDELIVERY_INTERRUPT));
154 	c.iqdroprss_to_iqesize = htobe16(V_FW_IQ_CMD_IQPCIECH(vi->pi->tx_chan) |
155 	    F_FW_IQ_CMD_IQGTSMODE |
156 	    V_FW_IQ_CMD_IQINTCNTTHRESH(0) |
157 	    V_FW_IQ_CMD_IQESIZE(ilog2(IQ_ESIZE) - 4));
158 	c.iqsize = htobe16(vi->qsize_rxq);
159 	c.iqaddr = htobe64(nm_rxq->iq_ba);
160 	if (cong >= 0) {
161 		c.iqns_to_fl0congen = htobe32(F_FW_IQ_CMD_IQFLINTCONGEN |
162 		    V_FW_IQ_CMD_FL0CNGCHMAP(cong) | F_FW_IQ_CMD_FL0CONGCIF |
163 		    F_FW_IQ_CMD_FL0CONGEN);
164 	}
165 	c.iqns_to_fl0congen |=
166 	    htobe32(V_FW_IQ_CMD_FL0HOSTFCMODE(X_HOSTFCMODE_NONE) |
167 		F_FW_IQ_CMD_FL0FETCHRO | F_FW_IQ_CMD_FL0DATARO |
168 		(fl_pad ? F_FW_IQ_CMD_FL0PADEN : 0) |
169 		(black_hole == 2 ? F_FW_IQ_CMD_FL0PACKEN : 0));
170 	c.fl0dcaen_to_fl0cidxfthresh =
171 	    htobe16(V_FW_IQ_CMD_FL0FBMIN(chip_id(sc) <= CHELSIO_T5 ?
172 		X_FETCHBURSTMIN_128B : X_FETCHBURSTMIN_64B_T6) |
173 		V_FW_IQ_CMD_FL0FBMAX(chip_id(sc) <= CHELSIO_T5 ?
174 		X_FETCHBURSTMAX_512B : X_FETCHBURSTMAX_256B));
175 	c.fl0size = htobe16(na->num_rx_desc / 8 + sp->spg_len / EQ_ESIZE);
176 	c.fl0addr = htobe64(nm_rxq->fl_ba);
177 
178 	rc = -t4_wr_mbox(sc, sc->mbox, &c, sizeof(c), &c);
179 	if (rc != 0) {
180 		device_printf(sc->dev,
181 		    "failed to create netmap ingress queue: %d\n", rc);
182 		return (rc);
183 	}
184 
185 	nm_rxq->iq_cidx = 0;
186 	MPASS(nm_rxq->iq_sidx == vi->qsize_rxq - sp->spg_len / IQ_ESIZE);
187 	nm_rxq->iq_gen = F_RSPD_GEN;
188 	nm_rxq->iq_cntxt_id = be16toh(c.iqid);
189 	nm_rxq->iq_abs_id = be16toh(c.physiqid);
190 	cntxt_id = nm_rxq->iq_cntxt_id - sc->sge.iq_start;
191 	if (cntxt_id >= sc->sge.niq) {
192 		panic ("%s: nm_rxq->iq_cntxt_id (%d) more than the max (%d)",
193 		    __func__, cntxt_id, sc->sge.niq - 1);
194 	}
195 	sc->sge.iqmap[cntxt_id] = (void *)nm_rxq;
196 
197 	nm_rxq->fl_cntxt_id = be16toh(c.fl0id);
198 	nm_rxq->fl_pidx = nm_rxq->fl_cidx = 0;
199 	MPASS(nm_rxq->fl_sidx == na->num_rx_desc);
200 	cntxt_id = nm_rxq->fl_cntxt_id - sc->sge.eq_start;
201 	if (cntxt_id >= sc->sge.neq) {
202 		panic("%s: nm_rxq->fl_cntxt_id (%d) more than the max (%d)",
203 		    __func__, cntxt_id, sc->sge.neq - 1);
204 	}
205 	sc->sge.eqmap[cntxt_id] = (void *)nm_rxq;
206 
207 	nm_rxq->fl_db_val = V_QID(nm_rxq->fl_cntxt_id) |
208 	    sc->chip_params->sge_fl_db;
209 
210 	if (chip_id(sc) >= CHELSIO_T5 && cong >= 0) {
211 		uint32_t param, val;
212 
213 		param = V_FW_PARAMS_MNEM(FW_PARAMS_MNEM_DMAQ) |
214 		    V_FW_PARAMS_PARAM_X(FW_PARAMS_PARAM_DMAQ_CONM_CTXT) |
215 		    V_FW_PARAMS_PARAM_YZ(nm_rxq->iq_cntxt_id);
216 		param = V_FW_PARAMS_MNEM(FW_PARAMS_MNEM_DMAQ) |
217 		    V_FW_PARAMS_PARAM_X(FW_PARAMS_PARAM_DMAQ_CONM_CTXT) |
218 		    V_FW_PARAMS_PARAM_YZ(nm_rxq->iq_cntxt_id);
219 		if (cong == 0)
220 			val = 1 << 19;
221 		else {
222 			val = 2 << 19;
223 			for (i = 0; i < 4; i++) {
224 				if (cong & (1 << i))
225 					val |= 1 << (i << 2);
226 			}
227 		}
228 
229 		rc = -t4_set_params(sc, sc->mbox, sc->pf, 0, 1, &param, &val);
230 		if (rc != 0) {
231 			/* report error but carry on */
232 			device_printf(sc->dev,
233 			    "failed to set congestion manager context for "
234 			    "ingress queue %d: %d\n", nm_rxq->iq_cntxt_id, rc);
235 		}
236 	}
237 
238 	t4_write_reg(sc, sc->sge_gts_reg,
239 	    V_INGRESSQID(nm_rxq->iq_cntxt_id) |
240 	    V_SEINTARM(V_QINTR_TIMER_IDX(holdoff_tmr_idx)));
241 
242 	return (rc);
243 }
244 
245 static int
246 free_nm_rxq_hwq(struct vi_info *vi, struct sge_nm_rxq *nm_rxq)
247 {
248 	struct adapter *sc = vi->pi->adapter;
249 	int rc;
250 
251 	rc = -t4_iq_free(sc, sc->mbox, sc->pf, 0, FW_IQ_TYPE_FL_INT_CAP,
252 	    nm_rxq->iq_cntxt_id, nm_rxq->fl_cntxt_id, 0xffff);
253 	if (rc != 0)
254 		device_printf(sc->dev, "%s: failed for iq %d, fl %d: %d\n",
255 		    __func__, nm_rxq->iq_cntxt_id, nm_rxq->fl_cntxt_id, rc);
256 	nm_rxq->iq_cntxt_id = INVALID_NM_RXQ_CNTXT_ID;
257 	return (rc);
258 }
259 
260 static int
261 alloc_nm_txq_hwq(struct vi_info *vi, struct sge_nm_txq *nm_txq)
262 {
263 	int rc, cntxt_id;
264 	size_t len;
265 	struct adapter *sc = vi->pi->adapter;
266 	struct netmap_adapter *na = NA(vi->ifp);
267 	struct fw_eq_eth_cmd c;
268 
269 	MPASS(na != NULL);
270 	MPASS(nm_txq->desc != NULL);
271 
272 	len = na->num_tx_desc * EQ_ESIZE + sc->params.sge.spg_len;
273 	bzero(nm_txq->desc, len);
274 
275 	bzero(&c, sizeof(c));
276 	c.op_to_vfn = htobe32(V_FW_CMD_OP(FW_EQ_ETH_CMD) | F_FW_CMD_REQUEST |
277 	    F_FW_CMD_WRITE | F_FW_CMD_EXEC | V_FW_EQ_ETH_CMD_PFN(sc->pf) |
278 	    V_FW_EQ_ETH_CMD_VFN(0));
279 	c.alloc_to_len16 = htobe32(F_FW_EQ_ETH_CMD_ALLOC |
280 	    F_FW_EQ_ETH_CMD_EQSTART | FW_LEN16(c));
281 	c.autoequiqe_to_viid = htobe32(F_FW_EQ_ETH_CMD_AUTOEQUIQE |
282 	    F_FW_EQ_ETH_CMD_AUTOEQUEQE | V_FW_EQ_ETH_CMD_VIID(vi->viid));
283 	c.fetchszm_to_iqid =
284 	    htobe32(V_FW_EQ_ETH_CMD_HOSTFCMODE(X_HOSTFCMODE_NONE) |
285 		V_FW_EQ_ETH_CMD_PCIECHN(vi->pi->tx_chan) | F_FW_EQ_ETH_CMD_FETCHRO |
286 		V_FW_EQ_ETH_CMD_IQID(sc->sge.nm_rxq[nm_txq->iqidx].iq_cntxt_id));
287 	c.dcaen_to_eqsize =
288 	    htobe32(V_FW_EQ_ETH_CMD_FBMIN(chip_id(sc) <= CHELSIO_T5 ?
289 		X_FETCHBURSTMIN_64B : X_FETCHBURSTMIN_64B_T6) |
290 		V_FW_EQ_ETH_CMD_FBMAX(X_FETCHBURSTMAX_512B) |
291 		V_FW_EQ_ETH_CMD_EQSIZE(len / EQ_ESIZE));
292 	c.eqaddr = htobe64(nm_txq->ba);
293 
294 	rc = -t4_wr_mbox(sc, sc->mbox, &c, sizeof(c), &c);
295 	if (rc != 0) {
296 		device_printf(vi->dev,
297 		    "failed to create netmap egress queue: %d\n", rc);
298 		return (rc);
299 	}
300 
301 	nm_txq->cntxt_id = G_FW_EQ_ETH_CMD_EQID(be32toh(c.eqid_pkd));
302 	cntxt_id = nm_txq->cntxt_id - sc->sge.eq_start;
303 	if (cntxt_id >= sc->sge.neq)
304 	    panic("%s: nm_txq->cntxt_id (%d) more than the max (%d)", __func__,
305 		cntxt_id, sc->sge.neq - 1);
306 	sc->sge.eqmap[cntxt_id] = (void *)nm_txq;
307 
308 	nm_txq->pidx = nm_txq->cidx = 0;
309 	MPASS(nm_txq->sidx == na->num_tx_desc);
310 	nm_txq->equiqidx = nm_txq->equeqidx = nm_txq->dbidx = 0;
311 
312 	nm_txq->doorbells = sc->doorbells;
313 	if (isset(&nm_txq->doorbells, DOORBELL_UDB) ||
314 	    isset(&nm_txq->doorbells, DOORBELL_UDBWC) ||
315 	    isset(&nm_txq->doorbells, DOORBELL_WCWR)) {
316 		uint32_t s_qpp = sc->params.sge.eq_s_qpp;
317 		uint32_t mask = (1 << s_qpp) - 1;
318 		volatile uint8_t *udb;
319 
320 		udb = sc->udbs_base + UDBS_DB_OFFSET;
321 		udb += (nm_txq->cntxt_id >> s_qpp) << PAGE_SHIFT;
322 		nm_txq->udb_qid = nm_txq->cntxt_id & mask;
323 		if (nm_txq->udb_qid >= PAGE_SIZE / UDBS_SEG_SIZE)
324 	    		clrbit(&nm_txq->doorbells, DOORBELL_WCWR);
325 		else {
326 			udb += nm_txq->udb_qid << UDBS_SEG_SHIFT;
327 			nm_txq->udb_qid = 0;
328 		}
329 		nm_txq->udb = (volatile void *)udb;
330 	}
331 
332 	return (rc);
333 }
334 
335 static int
336 free_nm_txq_hwq(struct vi_info *vi, struct sge_nm_txq *nm_txq)
337 {
338 	struct adapter *sc = vi->pi->adapter;
339 	int rc;
340 
341 	rc = -t4_eth_eq_free(sc, sc->mbox, sc->pf, 0, nm_txq->cntxt_id);
342 	if (rc != 0)
343 		device_printf(sc->dev, "%s: failed for eq %d: %d\n", __func__,
344 		    nm_txq->cntxt_id, rc);
345 	nm_txq->cntxt_id = INVALID_NM_TXQ_CNTXT_ID;
346 	return (rc);
347 }
348 
349 static int
350 cxgbe_netmap_on(struct adapter *sc, struct vi_info *vi, struct ifnet *ifp,
351     struct netmap_adapter *na)
352 {
353 	struct netmap_slot *slot;
354 	struct netmap_kring *kring;
355 	struct sge_nm_rxq *nm_rxq;
356 	struct sge_nm_txq *nm_txq;
357 	int rc, i, j, hwidx, defq, nrssq;
358 	struct rx_buf_info *rxb;
359 
360 	ASSERT_SYNCHRONIZED_OP(sc);
361 
362 	if ((vi->flags & VI_INIT_DONE) == 0 ||
363 	    (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
364 		return (EAGAIN);
365 
366 	rxb = &sc->sge.rx_buf_info[0];
367 	for (i = 0; i < SW_ZONE_SIZES; i++, rxb++) {
368 		if (rxb->size1 == NETMAP_BUF_SIZE(na)) {
369 			hwidx = rxb->hwidx1;
370 			break;
371 		}
372 		if (rxb->size2 == NETMAP_BUF_SIZE(na)) {
373 			hwidx = rxb->hwidx2;
374 			break;
375 		}
376 	}
377 	if (i >= SW_ZONE_SIZES) {
378 		if_printf(ifp, "no hwidx for netmap buffer size %d.\n",
379 		    NETMAP_BUF_SIZE(na));
380 		return (ENXIO);
381 	}
382 
383 	/* Must set caps before calling netmap_reset */
384 	nm_set_native_flags(na);
385 
386 	for_each_nm_rxq(vi, i, nm_rxq) {
387 		kring = na->rx_rings[nm_rxq->nid];
388 		if (!nm_kring_pending_on(kring) ||
389 		    nm_rxq->iq_cntxt_id != INVALID_NM_RXQ_CNTXT_ID)
390 			continue;
391 
392 		alloc_nm_rxq_hwq(vi, nm_rxq, tnl_cong(vi->pi, nm_cong_drop));
393 		nm_rxq->fl_hwidx = hwidx;
394 		slot = netmap_reset(na, NR_RX, i, 0);
395 		MPASS(slot != NULL);	/* XXXNM: error check, not assert */
396 
397 		/* We deal with 8 bufs at a time */
398 		MPASS((na->num_rx_desc & 7) == 0);
399 		MPASS(na->num_rx_desc == nm_rxq->fl_sidx);
400 		for (j = 0; j < nm_rxq->fl_sidx; j++) {
401 			uint64_t ba;
402 
403 			PNMB(na, &slot[j], &ba);
404 			MPASS(ba != 0);
405 			nm_rxq->fl_desc[j] = htobe64(ba | hwidx);
406 		}
407 		j = nm_rxq->fl_pidx = nm_rxq->fl_sidx - 8;
408 		MPASS((j & 7) == 0);
409 		j /= 8;	/* driver pidx to hardware pidx */
410 		wmb();
411 		t4_write_reg(sc, sc->sge_kdoorbell_reg,
412 		    nm_rxq->fl_db_val | V_PIDX(j));
413 
414 		(void) atomic_cmpset_int(&nm_rxq->nm_state, NM_OFF, NM_ON);
415 	}
416 
417 	for_each_nm_txq(vi, i, nm_txq) {
418 		kring = na->tx_rings[nm_txq->nid];
419 		if (!nm_kring_pending_on(kring) ||
420 		    nm_txq->cntxt_id != INVALID_NM_TXQ_CNTXT_ID)
421 			continue;
422 
423 		alloc_nm_txq_hwq(vi, nm_txq);
424 		slot = netmap_reset(na, NR_TX, i, 0);
425 		MPASS(slot != NULL);	/* XXXNM: error check, not assert */
426 	}
427 
428 	if (vi->nm_rss == NULL) {
429 		vi->nm_rss = malloc(vi->rss_size * sizeof(uint16_t), M_CXGBE,
430 		    M_ZERO | M_WAITOK);
431 	}
432 
433 	MPASS(vi->nnmrxq > 0);
434 	if (nm_split_rss == 0 || vi->nnmrxq == 1) {
435 		for (i = 0; i < vi->rss_size;) {
436 			for_each_nm_rxq(vi, j, nm_rxq) {
437 				vi->nm_rss[i++] = nm_rxq->iq_abs_id;
438 				if (i == vi->rss_size)
439 					break;
440 			}
441 		}
442 		defq = vi->nm_rss[0];
443 	} else {
444 		/* We have multiple queues and we want to split the table. */
445 		MPASS(nm_split_rss != 0);
446 		MPASS(vi->nnmrxq > 1);
447 
448 		nm_rxq = &sc->sge.nm_rxq[vi->first_nm_rxq];
449 		nrssq = vi->nnmrxq;
450 		if (vi->nnmrxq & 1) {
451 			/*
452 			 * Odd number of queues. The first rxq is designated the
453 			 * default queue, the rest are split evenly.
454 			 */
455 			defq = nm_rxq->iq_abs_id;
456 			nm_rxq++;
457 			nrssq--;
458 		} else {
459 			/*
460 			 * Even number of queues split into two halves.  The
461 			 * first rxq in one of the halves is designated the
462 			 * default queue.
463 			 */
464 #if 1
465 			/* First rxq in the first half. */
466 			defq = nm_rxq->iq_abs_id;
467 #else
468 			/* First rxq in the second half. */
469 			defq = nm_rxq[vi->nnmrxq / 2].iq_abs_id;
470 #endif
471 		}
472 
473 		i = 0;
474 		while (i < vi->rss_size / 2) {
475 			for (j = 0; j < nrssq / 2; j++) {
476 				vi->nm_rss[i++] = nm_rxq[j].iq_abs_id;
477 				if (i == vi->rss_size / 2)
478 					break;
479 			}
480 		}
481 		while (i < vi->rss_size) {
482 			for (j = nrssq / 2; j < nrssq; j++) {
483 				vi->nm_rss[i++] = nm_rxq[j].iq_abs_id;
484 				if (i == vi->rss_size)
485 					break;
486 			}
487 		}
488 	}
489 	rc = -t4_config_rss_range(sc, sc->mbox, vi->viid, 0, vi->rss_size,
490 	    vi->nm_rss, vi->rss_size);
491 	if (rc != 0)
492 		if_printf(ifp, "netmap rss_config failed: %d\n", rc);
493 
494 	rc = -t4_config_vi_rss(sc, sc->mbox, vi->viid, vi->hashen, defq, 0, 0);
495 	if (rc != 0)
496 		if_printf(ifp, "netmap rss hash/defaultq config failed: %d\n", rc);
497 
498 	return (rc);
499 }
500 
501 static int
502 cxgbe_netmap_off(struct adapter *sc, struct vi_info *vi, struct ifnet *ifp,
503     struct netmap_adapter *na)
504 {
505 	struct netmap_kring *kring;
506 	int rc, i;
507 	struct sge_nm_txq *nm_txq;
508 	struct sge_nm_rxq *nm_rxq;
509 
510 	ASSERT_SYNCHRONIZED_OP(sc);
511 
512 	if (!nm_netmap_on(na))
513 		return (0);
514 
515 	if ((vi->flags & VI_INIT_DONE) == 0)
516 		return (0);
517 
518 	rc = -t4_config_rss_range(sc, sc->mbox, vi->viid, 0, vi->rss_size,
519 	    vi->rss, vi->rss_size);
520 	if (rc != 0)
521 		if_printf(ifp, "failed to restore RSS config: %d\n", rc);
522 	rc = -t4_config_vi_rss(sc, sc->mbox, vi->viid, vi->hashen, vi->rss[0], 0, 0);
523 	if (rc != 0)
524 		if_printf(ifp, "failed to restore RSS hash/defaultq: %d\n", rc);
525 	nm_clear_native_flags(na);
526 
527 	for_each_nm_txq(vi, i, nm_txq) {
528 		struct sge_qstat *spg = (void *)&nm_txq->desc[nm_txq->sidx];
529 
530 		kring = na->tx_rings[nm_txq->nid];
531 		if (!nm_kring_pending_off(kring) ||
532 		    nm_txq->cntxt_id == INVALID_NM_TXQ_CNTXT_ID)
533 			continue;
534 
535 		/* Wait for hw pidx to catch up ... */
536 		while (be16toh(nm_txq->pidx) != spg->pidx)
537 			pause("nmpidx", 1);
538 
539 		/* ... and then for the cidx. */
540 		while (spg->pidx != spg->cidx)
541 			pause("nmcidx", 1);
542 
543 		free_nm_txq_hwq(vi, nm_txq);
544 	}
545 	for_each_nm_rxq(vi, i, nm_rxq) {
546 		kring = na->rx_rings[nm_rxq->nid];
547 		if (!nm_kring_pending_off(kring) ||
548 		    nm_rxq->iq_cntxt_id == INVALID_NM_RXQ_CNTXT_ID)
549 			continue;
550 
551 		while (!atomic_cmpset_int(&nm_rxq->nm_state, NM_ON, NM_OFF))
552 			pause("nmst", 1);
553 
554 		free_nm_rxq_hwq(vi, nm_rxq);
555 	}
556 
557 	return (rc);
558 }
559 
560 static int
561 cxgbe_netmap_reg(struct netmap_adapter *na, int on)
562 {
563 	struct ifnet *ifp = na->ifp;
564 	struct vi_info *vi = ifp->if_softc;
565 	struct adapter *sc = vi->pi->adapter;
566 	int rc;
567 
568 	rc = begin_synchronized_op(sc, vi, SLEEP_OK | INTR_OK, "t4nmreg");
569 	if (rc != 0)
570 		return (rc);
571 	if (on)
572 		rc = cxgbe_netmap_on(sc, vi, ifp, na);
573 	else
574 		rc = cxgbe_netmap_off(sc, vi, ifp, na);
575 	end_synchronized_op(sc, 0);
576 
577 	return (rc);
578 }
579 
580 /* How many packets can a single type1 WR carry in n descriptors */
581 static inline int
582 ndesc_to_npkt(const int n)
583 {
584 
585 	MPASS(n > 0 && n <= SGE_MAX_WR_NDESC);
586 
587 	return (n * 2 - 1);
588 }
589 #define MAX_NPKT_IN_TYPE1_WR	(ndesc_to_npkt(SGE_MAX_WR_NDESC))
590 
591 /*
592  * Space (in descriptors) needed for a type1 WR (TX_PKTS or TX_PKTS2) that
593  * carries n packets
594  */
595 static inline int
596 npkt_to_ndesc(const int n)
597 {
598 
599 	MPASS(n > 0 && n <= MAX_NPKT_IN_TYPE1_WR);
600 
601 	return ((n + 2) / 2);
602 }
603 
604 /*
605  * Space (in 16B units) needed for a type1 WR (TX_PKTS or TX_PKTS2) that
606  * carries n packets
607  */
608 static inline int
609 npkt_to_len16(const int n)
610 {
611 
612 	MPASS(n > 0 && n <= MAX_NPKT_IN_TYPE1_WR);
613 
614 	return (n * 2 + 1);
615 }
616 
617 #define NMIDXDIFF(q, idx) IDXDIFF((q)->pidx, (q)->idx, (q)->sidx)
618 
619 static void
620 ring_nm_txq_db(struct adapter *sc, struct sge_nm_txq *nm_txq)
621 {
622 	int n;
623 	u_int db = nm_txq->doorbells;
624 
625 	MPASS(nm_txq->pidx != nm_txq->dbidx);
626 
627 	n = NMIDXDIFF(nm_txq, dbidx);
628 	if (n > 1)
629 		clrbit(&db, DOORBELL_WCWR);
630 	wmb();
631 
632 	switch (ffs(db) - 1) {
633 	case DOORBELL_UDB:
634 		*nm_txq->udb = htole32(V_QID(nm_txq->udb_qid) | V_PIDX(n));
635 		break;
636 
637 	case DOORBELL_WCWR: {
638 		volatile uint64_t *dst, *src;
639 
640 		/*
641 		 * Queues whose 128B doorbell segment fits in the page do not
642 		 * use relative qid (udb_qid is always 0).  Only queues with
643 		 * doorbell segments can do WCWR.
644 		 */
645 		KASSERT(nm_txq->udb_qid == 0 && n == 1,
646 		    ("%s: inappropriate doorbell (0x%x, %d, %d) for nm_txq %p",
647 		    __func__, nm_txq->doorbells, n, nm_txq->pidx, nm_txq));
648 
649 		dst = (volatile void *)((uintptr_t)nm_txq->udb +
650 		    UDBS_WR_OFFSET - UDBS_DB_OFFSET);
651 		src = (void *)&nm_txq->desc[nm_txq->dbidx];
652 		while (src != (void *)&nm_txq->desc[nm_txq->dbidx + 1])
653 			*dst++ = *src++;
654 		wmb();
655 		break;
656 	}
657 
658 	case DOORBELL_UDBWC:
659 		*nm_txq->udb = htole32(V_QID(nm_txq->udb_qid) | V_PIDX(n));
660 		wmb();
661 		break;
662 
663 	case DOORBELL_KDB:
664 		t4_write_reg(sc, sc->sge_kdoorbell_reg,
665 		    V_QID(nm_txq->cntxt_id) | V_PIDX(n));
666 		break;
667 	}
668 	nm_txq->dbidx = nm_txq->pidx;
669 }
670 
671 /*
672  * Write work requests to send 'npkt' frames and ring the doorbell to send them
673  * on their way.  No need to check for wraparound.
674  */
675 static void
676 cxgbe_nm_tx(struct adapter *sc, struct sge_nm_txq *nm_txq,
677     struct netmap_kring *kring, int npkt, int npkt_remaining)
678 {
679 	struct netmap_ring *ring = kring->ring;
680 	struct netmap_slot *slot;
681 	const u_int lim = kring->nkr_num_slots - 1;
682 	struct fw_eth_tx_pkts_wr *wr = (void *)&nm_txq->desc[nm_txq->pidx];
683 	uint16_t len;
684 	uint64_t ba;
685 	struct cpl_tx_pkt_core *cpl;
686 	struct ulptx_sgl *usgl;
687 	int i, n;
688 
689 	while (npkt) {
690 		n = min(npkt, MAX_NPKT_IN_TYPE1_WR);
691 		len = 0;
692 
693 		wr = (void *)&nm_txq->desc[nm_txq->pidx];
694 		wr->op_pkd = nm_txq->op_pkd;
695 		wr->equiq_to_len16 = htobe32(V_FW_WR_LEN16(npkt_to_len16(n)));
696 		wr->npkt = n;
697 		wr->r3 = 0;
698 		wr->type = 1;
699 		cpl = (void *)(wr + 1);
700 
701 		for (i = 0; i < n; i++) {
702 			slot = &ring->slot[kring->nr_hwcur];
703 			PNMB(kring->na, slot, &ba);
704 			MPASS(ba != 0);
705 
706 			cpl->ctrl0 = nm_txq->cpl_ctrl0;
707 			cpl->pack = 0;
708 			cpl->len = htobe16(slot->len);
709 			cpl->ctrl1 = nm_txcsum ? 0 :
710 			    htobe64(F_TXPKT_IPCSUM_DIS | F_TXPKT_L4CSUM_DIS);
711 
712 			usgl = (void *)(cpl + 1);
713 			usgl->cmd_nsge = htobe32(V_ULPTX_CMD(ULP_TX_SC_DSGL) |
714 			    V_ULPTX_NSGE(1));
715 			usgl->len0 = htobe32(slot->len);
716 			usgl->addr0 = htobe64(ba);
717 
718 			slot->flags &= ~(NS_REPORT | NS_BUF_CHANGED);
719 			cpl = (void *)(usgl + 1);
720 			MPASS(slot->len + len <= UINT16_MAX);
721 			len += slot->len;
722 			kring->nr_hwcur = nm_next(kring->nr_hwcur, lim);
723 		}
724 		wr->plen = htobe16(len);
725 
726 		npkt -= n;
727 		nm_txq->pidx += npkt_to_ndesc(n);
728 		MPASS(nm_txq->pidx <= nm_txq->sidx);
729 		if (__predict_false(nm_txq->pidx == nm_txq->sidx)) {
730 			/*
731 			 * This routine doesn't know how to write WRs that wrap
732 			 * around.  Make sure it wasn't asked to.
733 			 */
734 			MPASS(npkt == 0);
735 			nm_txq->pidx = 0;
736 		}
737 
738 		if (npkt == 0 && npkt_remaining == 0) {
739 			/* All done. */
740 			if (lazy_tx_credit_flush == 0) {
741 				wr->equiq_to_len16 |= htobe32(F_FW_WR_EQUEQ |
742 				    F_FW_WR_EQUIQ);
743 				nm_txq->equeqidx = nm_txq->pidx;
744 				nm_txq->equiqidx = nm_txq->pidx;
745 			}
746 			ring_nm_txq_db(sc, nm_txq);
747 			return;
748 		}
749 
750 		if (NMIDXDIFF(nm_txq, equiqidx) >= nm_txq->sidx / 2) {
751 			wr->equiq_to_len16 |= htobe32(F_FW_WR_EQUEQ |
752 			    F_FW_WR_EQUIQ);
753 			nm_txq->equeqidx = nm_txq->pidx;
754 			nm_txq->equiqidx = nm_txq->pidx;
755 		} else if (NMIDXDIFF(nm_txq, equeqidx) >= 64) {
756 			wr->equiq_to_len16 |= htobe32(F_FW_WR_EQUEQ);
757 			nm_txq->equeqidx = nm_txq->pidx;
758 		}
759 		if (NMIDXDIFF(nm_txq, dbidx) >= 2 * SGE_MAX_WR_NDESC)
760 			ring_nm_txq_db(sc, nm_txq);
761 	}
762 
763 	/* Will get called again. */
764 	MPASS(npkt_remaining);
765 }
766 
767 /* How many contiguous free descriptors starting at pidx */
768 static inline int
769 contiguous_ndesc_available(struct sge_nm_txq *nm_txq)
770 {
771 
772 	if (nm_txq->cidx > nm_txq->pidx)
773 		return (nm_txq->cidx - nm_txq->pidx - 1);
774 	else if (nm_txq->cidx > 0)
775 		return (nm_txq->sidx - nm_txq->pidx);
776 	else
777 		return (nm_txq->sidx - nm_txq->pidx - 1);
778 }
779 
780 static int
781 reclaim_nm_tx_desc(struct sge_nm_txq *nm_txq)
782 {
783 	struct sge_qstat *spg = (void *)&nm_txq->desc[nm_txq->sidx];
784 	uint16_t hw_cidx = spg->cidx;	/* snapshot */
785 	struct fw_eth_tx_pkts_wr *wr;
786 	int n = 0;
787 
788 	hw_cidx = be16toh(hw_cidx);
789 
790 	while (nm_txq->cidx != hw_cidx) {
791 		wr = (void *)&nm_txq->desc[nm_txq->cidx];
792 
793 		MPASS(wr->op_pkd == htobe32(V_FW_WR_OP(FW_ETH_TX_PKTS_WR)) ||
794 		    wr->op_pkd == htobe32(V_FW_WR_OP(FW_ETH_TX_PKTS2_WR)));
795 		MPASS(wr->type == 1);
796 		MPASS(wr->npkt > 0 && wr->npkt <= MAX_NPKT_IN_TYPE1_WR);
797 
798 		n += wr->npkt;
799 		nm_txq->cidx += npkt_to_ndesc(wr->npkt);
800 
801 		/*
802 		 * We never sent a WR that wrapped around so the credits coming
803 		 * back, WR by WR, should never cause the cidx to wrap around
804 		 * either.
805 		 */
806 		MPASS(nm_txq->cidx <= nm_txq->sidx);
807 		if (__predict_false(nm_txq->cidx == nm_txq->sidx))
808 			nm_txq->cidx = 0;
809 	}
810 
811 	return (n);
812 }
813 
814 static int
815 cxgbe_netmap_txsync(struct netmap_kring *kring, int flags)
816 {
817 	struct netmap_adapter *na = kring->na;
818 	struct ifnet *ifp = na->ifp;
819 	struct vi_info *vi = ifp->if_softc;
820 	struct adapter *sc = vi->pi->adapter;
821 	struct sge_nm_txq *nm_txq = &sc->sge.nm_txq[vi->first_nm_txq + kring->ring_id];
822 	const u_int head = kring->rhead;
823 	u_int reclaimed = 0;
824 	int n, d, npkt_remaining, ndesc_remaining;
825 
826 	/*
827 	 * Tx was at kring->nr_hwcur last time around and now we need to advance
828 	 * to kring->rhead.  Note that the driver's pidx moves independent of
829 	 * netmap's kring->nr_hwcur (pidx counts descriptors and the relation
830 	 * between descriptors and frames isn't 1:1).
831 	 */
832 
833 	npkt_remaining = head >= kring->nr_hwcur ? head - kring->nr_hwcur :
834 	    kring->nkr_num_slots - kring->nr_hwcur + head;
835 	while (npkt_remaining) {
836 		reclaimed += reclaim_nm_tx_desc(nm_txq);
837 		ndesc_remaining = contiguous_ndesc_available(nm_txq);
838 		/* Can't run out of descriptors with packets still remaining */
839 		MPASS(ndesc_remaining > 0);
840 
841 		/* # of desc needed to tx all remaining packets */
842 		d = (npkt_remaining / MAX_NPKT_IN_TYPE1_WR) * SGE_MAX_WR_NDESC;
843 		if (npkt_remaining % MAX_NPKT_IN_TYPE1_WR)
844 			d += npkt_to_ndesc(npkt_remaining % MAX_NPKT_IN_TYPE1_WR);
845 
846 		if (d <= ndesc_remaining)
847 			n = npkt_remaining;
848 		else {
849 			/* Can't send all, calculate how many can be sent */
850 			n = (ndesc_remaining / SGE_MAX_WR_NDESC) *
851 			    MAX_NPKT_IN_TYPE1_WR;
852 			if (ndesc_remaining % SGE_MAX_WR_NDESC)
853 				n += ndesc_to_npkt(ndesc_remaining % SGE_MAX_WR_NDESC);
854 		}
855 
856 		/* Send n packets and update nm_txq->pidx and kring->nr_hwcur */
857 		npkt_remaining -= n;
858 		cxgbe_nm_tx(sc, nm_txq, kring, n, npkt_remaining);
859 	}
860 	MPASS(npkt_remaining == 0);
861 	MPASS(kring->nr_hwcur == head);
862 	MPASS(nm_txq->dbidx == nm_txq->pidx);
863 
864 	/*
865 	 * Second part: reclaim buffers for completed transmissions.
866 	 */
867 	if (reclaimed || flags & NAF_FORCE_RECLAIM || nm_kr_txempty(kring)) {
868 		reclaimed += reclaim_nm_tx_desc(nm_txq);
869 		kring->nr_hwtail += reclaimed;
870 		if (kring->nr_hwtail >= kring->nkr_num_slots)
871 			kring->nr_hwtail -= kring->nkr_num_slots;
872 	}
873 
874 	return (0);
875 }
876 
877 static int
878 cxgbe_netmap_rxsync(struct netmap_kring *kring, int flags)
879 {
880 	struct netmap_adapter *na = kring->na;
881 	struct netmap_ring *ring = kring->ring;
882 	struct ifnet *ifp = na->ifp;
883 	struct vi_info *vi = ifp->if_softc;
884 	struct adapter *sc = vi->pi->adapter;
885 	struct sge_nm_rxq *nm_rxq = &sc->sge.nm_rxq[vi->first_nm_rxq + kring->ring_id];
886 	u_int const head = kring->rhead;
887 	u_int n;
888 	int force_update = (flags & NAF_FORCE_READ) || kring->nr_kflags & NKR_PENDINTR;
889 
890 	if (black_hole)
891 		return (0);	/* No updates ever. */
892 
893 	if (netmap_no_pendintr || force_update) {
894 		kring->nr_hwtail = atomic_load_acq_32(&nm_rxq->fl_cidx);
895 		kring->nr_kflags &= ~NKR_PENDINTR;
896 	}
897 
898 	if (nm_rxq->fl_db_saved > 0 && starve_fl == 0) {
899 		wmb();
900 		t4_write_reg(sc, sc->sge_kdoorbell_reg,
901 		    nm_rxq->fl_db_val | V_PIDX(nm_rxq->fl_db_saved));
902 		nm_rxq->fl_db_saved = 0;
903 	}
904 
905 	/* Userspace done with buffers from kring->nr_hwcur to head */
906 	n = head >= kring->nr_hwcur ? head - kring->nr_hwcur :
907 	    kring->nkr_num_slots - kring->nr_hwcur + head;
908 	n &= ~7U;
909 	if (n > 0) {
910 		u_int fl_pidx = nm_rxq->fl_pidx;
911 		struct netmap_slot *slot = &ring->slot[fl_pidx];
912 		uint64_t ba;
913 		int i, dbinc = 0, hwidx = nm_rxq->fl_hwidx;
914 
915 		/*
916 		 * We always deal with 8 buffers at a time.  We must have
917 		 * stopped at an 8B boundary (fl_pidx) last time around and we
918 		 * must have a multiple of 8B buffers to give to the freelist.
919 		 */
920 		MPASS((fl_pidx & 7) == 0);
921 		MPASS((n & 7) == 0);
922 
923 		IDXINCR(kring->nr_hwcur, n, kring->nkr_num_slots);
924 		IDXINCR(nm_rxq->fl_pidx, n, nm_rxq->fl_sidx2);
925 
926 		while (n > 0) {
927 			for (i = 0; i < 8; i++, fl_pidx++, slot++) {
928 				PNMB(na, slot, &ba);
929 				MPASS(ba != 0);
930 				nm_rxq->fl_desc[fl_pidx] = htobe64(ba | hwidx);
931 				slot->flags &= ~NS_BUF_CHANGED;
932 				MPASS(fl_pidx <= nm_rxq->fl_sidx2);
933 			}
934 			n -= 8;
935 			if (fl_pidx == nm_rxq->fl_sidx2) {
936 				fl_pidx = 0;
937 				slot = &ring->slot[0];
938 			}
939 			if (++dbinc == 8 && n >= 32) {
940 				wmb();
941 				if (starve_fl)
942 					nm_rxq->fl_db_saved += dbinc;
943 				else {
944 					t4_write_reg(sc, sc->sge_kdoorbell_reg,
945 					    nm_rxq->fl_db_val | V_PIDX(dbinc));
946 				}
947 				dbinc = 0;
948 			}
949 		}
950 		MPASS(nm_rxq->fl_pidx == fl_pidx);
951 
952 		if (dbinc > 0) {
953 			wmb();
954 			if (starve_fl)
955 				nm_rxq->fl_db_saved += dbinc;
956 			else {
957 				t4_write_reg(sc, sc->sge_kdoorbell_reg,
958 				    nm_rxq->fl_db_val | V_PIDX(dbinc));
959 			}
960 		}
961 	}
962 
963 	return (0);
964 }
965 
966 void
967 cxgbe_nm_attach(struct vi_info *vi)
968 {
969 	struct port_info *pi;
970 	struct adapter *sc;
971 	struct netmap_adapter na;
972 
973 	MPASS(vi->nnmrxq > 0);
974 	MPASS(vi->ifp != NULL);
975 
976 	pi = vi->pi;
977 	sc = pi->adapter;
978 
979 	bzero(&na, sizeof(na));
980 
981 	na.ifp = vi->ifp;
982 	na.na_flags = NAF_BDG_MAYSLEEP;
983 
984 	/* Netmap doesn't know about the space reserved for the status page. */
985 	na.num_tx_desc = vi->qsize_txq - sc->params.sge.spg_len / EQ_ESIZE;
986 
987 	/*
988 	 * The freelist's cidx/pidx drives netmap's rx cidx/pidx.  So
989 	 * num_rx_desc is based on the number of buffers that can be held in the
990 	 * freelist, and not the number of entries in the iq.  (These two are
991 	 * not exactly the same due to the space taken up by the status page).
992 	 */
993 	na.num_rx_desc = rounddown(vi->qsize_rxq, 8);
994 	na.nm_txsync = cxgbe_netmap_txsync;
995 	na.nm_rxsync = cxgbe_netmap_rxsync;
996 	na.nm_register = cxgbe_netmap_reg;
997 	na.num_tx_rings = vi->nnmtxq;
998 	na.num_rx_rings = vi->nnmrxq;
999 	na.rx_buf_maxsize = MAX_MTU;
1000 	netmap_attach(&na);	/* This adds IFCAP_NETMAP to if_capabilities */
1001 }
1002 
1003 void
1004 cxgbe_nm_detach(struct vi_info *vi)
1005 {
1006 
1007 	MPASS(vi->nnmrxq > 0);
1008 	MPASS(vi->ifp != NULL);
1009 
1010 	netmap_detach(vi->ifp);
1011 }
1012 
1013 static inline const void *
1014 unwrap_nm_fw6_msg(const struct cpl_fw6_msg *cpl)
1015 {
1016 
1017 	MPASS(cpl->type == FW_TYPE_RSSCPL || cpl->type == FW6_TYPE_RSSCPL);
1018 
1019 	/* data[0] is RSS header */
1020 	return (&cpl->data[1]);
1021 }
1022 
1023 static void
1024 handle_nm_sge_egr_update(struct adapter *sc, struct ifnet *ifp,
1025     const struct cpl_sge_egr_update *egr)
1026 {
1027 	uint32_t oq;
1028 	struct sge_nm_txq *nm_txq;
1029 
1030 	oq = be32toh(egr->opcode_qid);
1031 	MPASS(G_CPL_OPCODE(oq) == CPL_SGE_EGR_UPDATE);
1032 	nm_txq = (void *)sc->sge.eqmap[G_EGR_QID(oq) - sc->sge.eq_start];
1033 
1034 	netmap_tx_irq(ifp, nm_txq->nid);
1035 }
1036 
1037 void
1038 service_nm_rxq(struct sge_nm_rxq *nm_rxq)
1039 {
1040 	struct vi_info *vi = nm_rxq->vi;
1041 	struct adapter *sc = vi->pi->adapter;
1042 	struct ifnet *ifp = vi->ifp;
1043 	struct netmap_adapter *na = NA(ifp);
1044 	struct netmap_kring *kring = na->rx_rings[nm_rxq->nid];
1045 	struct netmap_ring *ring = kring->ring;
1046 	struct iq_desc *d = &nm_rxq->iq_desc[nm_rxq->iq_cidx];
1047 	const void *cpl;
1048 	uint32_t lq;
1049 	u_int work = 0;
1050 	uint8_t opcode;
1051 	uint32_t fl_cidx = atomic_load_acq_32(&nm_rxq->fl_cidx);
1052 	u_int fl_credits = fl_cidx & 7;
1053 	u_int ndesc = 0;	/* desc processed since last cidx update */
1054 	u_int nframes = 0;	/* frames processed since last netmap wakeup */
1055 
1056 	while ((d->rsp.u.type_gen & F_RSPD_GEN) == nm_rxq->iq_gen) {
1057 
1058 		rmb();
1059 
1060 		lq = be32toh(d->rsp.pldbuflen_qid);
1061 		opcode = d->rss.opcode;
1062 		cpl = &d->cpl[0];
1063 
1064 		switch (G_RSPD_TYPE(d->rsp.u.type_gen)) {
1065 		case X_RSPD_TYPE_FLBUF:
1066 
1067 			/* fall through */
1068 
1069 		case X_RSPD_TYPE_CPL:
1070 			MPASS(opcode < NUM_CPL_CMDS);
1071 
1072 			switch (opcode) {
1073 			case CPL_FW4_MSG:
1074 			case CPL_FW6_MSG:
1075 				cpl = unwrap_nm_fw6_msg(cpl);
1076 				/* fall through */
1077 			case CPL_SGE_EGR_UPDATE:
1078 				handle_nm_sge_egr_update(sc, ifp, cpl);
1079 				break;
1080 			case CPL_RX_PKT:
1081 				ring->slot[fl_cidx].len = G_RSPD_LEN(lq) -
1082 				    sc->params.sge.fl_pktshift;
1083 				ring->slot[fl_cidx].flags = 0;
1084 				nframes++;
1085 				if (!(lq & F_RSPD_NEWBUF)) {
1086 					MPASS(black_hole == 2);
1087 					break;
1088 				}
1089 				fl_credits++;
1090 				if (__predict_false(++fl_cidx == nm_rxq->fl_sidx))
1091 					fl_cidx = 0;
1092 				break;
1093 			default:
1094 				panic("%s: unexpected opcode 0x%x on nm_rxq %p",
1095 				    __func__, opcode, nm_rxq);
1096 			}
1097 			break;
1098 
1099 		case X_RSPD_TYPE_INTR:
1100 			/* Not equipped to handle forwarded interrupts. */
1101 			panic("%s: netmap queue received interrupt for iq %u\n",
1102 			    __func__, lq);
1103 
1104 		default:
1105 			panic("%s: illegal response type %d on nm_rxq %p",
1106 			    __func__, G_RSPD_TYPE(d->rsp.u.type_gen), nm_rxq);
1107 		}
1108 
1109 		d++;
1110 		if (__predict_false(++nm_rxq->iq_cidx == nm_rxq->iq_sidx)) {
1111 			nm_rxq->iq_cidx = 0;
1112 			d = &nm_rxq->iq_desc[0];
1113 			nm_rxq->iq_gen ^= F_RSPD_GEN;
1114 		}
1115 
1116 		if (__predict_false(++nframes == rx_nframes) && !black_hole) {
1117 			atomic_store_rel_32(&nm_rxq->fl_cidx, fl_cidx);
1118 			netmap_rx_irq(ifp, nm_rxq->nid, &work);
1119 			nframes = 0;
1120 		}
1121 
1122 		if (__predict_false(++ndesc == rx_ndesc)) {
1123 			if (black_hole && fl_credits >= 8) {
1124 				fl_credits /= 8;
1125 				IDXINCR(nm_rxq->fl_pidx, fl_credits * 8,
1126 				    nm_rxq->fl_sidx);
1127 				t4_write_reg(sc, sc->sge_kdoorbell_reg,
1128 				    nm_rxq->fl_db_val | V_PIDX(fl_credits));
1129 				fl_credits = fl_cidx & 7;
1130 			}
1131 			t4_write_reg(sc, sc->sge_gts_reg,
1132 			    V_CIDXINC(ndesc) |
1133 			    V_INGRESSQID(nm_rxq->iq_cntxt_id) |
1134 			    V_SEINTARM(V_QINTR_TIMER_IDX(X_TIMERREG_UPDATE_CIDX)));
1135 			ndesc = 0;
1136 		}
1137 	}
1138 
1139 	atomic_store_rel_32(&nm_rxq->fl_cidx, fl_cidx);
1140 	if (black_hole) {
1141 		fl_credits /= 8;
1142 		IDXINCR(nm_rxq->fl_pidx, fl_credits * 8, nm_rxq->fl_sidx);
1143 		t4_write_reg(sc, sc->sge_kdoorbell_reg,
1144 		    nm_rxq->fl_db_val | V_PIDX(fl_credits));
1145 	} else if (nframes > 0)
1146 		netmap_rx_irq(ifp, nm_rxq->nid, &work);
1147 
1148     	t4_write_reg(sc, sc->sge_gts_reg, V_CIDXINC(ndesc) |
1149 	    V_INGRESSQID((u32)nm_rxq->iq_cntxt_id) |
1150 	    V_SEINTARM(V_QINTR_TIMER_IDX(holdoff_tmr_idx)));
1151 }
1152 #endif
1153