xref: /freebsd/sys/dev/cxgbe/t4_netmap.c (revision 852ba100814e41898dc6e673fe0af017084e411d)
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 SYSCTL_NODE(_hw, OID_AUTO, cxgbe, CTLFLAG_RD, 0, "cxgbe netmap parameters");
61 
62 /*
63  * 0 = normal netmap rx
64  * 1 = black hole
65  * 2 = supermassive black hole (buffer packing enabled)
66  */
67 int black_hole = 0;
68 SYSCTL_INT(_hw_cxgbe, OID_AUTO, nm_black_hole, CTLFLAG_RDTUN, &black_hole, 0,
69     "Sink incoming packets.");
70 
71 int rx_ndesc = 256;
72 SYSCTL_INT(_hw_cxgbe, OID_AUTO, nm_rx_ndesc, CTLFLAG_RWTUN,
73     &rx_ndesc, 0, "# of rx descriptors after which the hw cidx is updated.");
74 
75 int holdoff_tmr_idx = 2;
76 SYSCTL_INT(_hw_cxgbe, OID_AUTO, nm_holdoff_tmr_idx, CTLFLAG_RWTUN,
77     &holdoff_tmr_idx, 0, "Holdoff timer index for netmap rx queues.");
78 
79 /*
80  * Congestion drops.
81  * -1: no congestion feedback (not recommended).
82  *  0: backpressure the channel instead of dropping packets right away.
83  *  1: no backpressure, drop packets for the congested queue immediately.
84  */
85 static int nm_cong_drop = 1;
86 TUNABLE_INT("hw.cxgbe.nm_cong_drop", &nm_cong_drop);
87 
88 static int
89 alloc_nm_rxq_hwq(struct vi_info *vi, struct sge_nm_rxq *nm_rxq, int cong)
90 {
91 	int rc, cntxt_id, i;
92 	__be32 v;
93 	struct adapter *sc = vi->pi->adapter;
94 	struct sge_params *sp = &sc->params.sge;
95 	struct netmap_adapter *na = NA(vi->ifp);
96 	struct fw_iq_cmd c;
97 
98 	MPASS(na != NULL);
99 	MPASS(nm_rxq->iq_desc != NULL);
100 	MPASS(nm_rxq->fl_desc != NULL);
101 
102 	bzero(nm_rxq->iq_desc, vi->qsize_rxq * IQ_ESIZE);
103 	bzero(nm_rxq->fl_desc, na->num_rx_desc * EQ_ESIZE + sp->spg_len);
104 
105 	bzero(&c, sizeof(c));
106 	c.op_to_vfn = htobe32(V_FW_CMD_OP(FW_IQ_CMD) | F_FW_CMD_REQUEST |
107 	    F_FW_CMD_WRITE | F_FW_CMD_EXEC | V_FW_IQ_CMD_PFN(sc->pf) |
108 	    V_FW_IQ_CMD_VFN(0));
109 	c.alloc_to_len16 = htobe32(F_FW_IQ_CMD_ALLOC | F_FW_IQ_CMD_IQSTART |
110 	    FW_LEN16(c));
111 	if (vi->flags & INTR_RXQ) {
112 		KASSERT(nm_rxq->intr_idx < sc->intr_count,
113 		    ("%s: invalid direct intr_idx %d", __func__,
114 		    nm_rxq->intr_idx));
115 		v = V_FW_IQ_CMD_IQANDSTINDEX(nm_rxq->intr_idx);
116 	} else {
117 		CXGBE_UNIMPLEMENTED(__func__);	/* XXXNM: needs review */
118 		v = V_FW_IQ_CMD_IQANDSTINDEX(nm_rxq->intr_idx) |
119 		    F_FW_IQ_CMD_IQANDST;
120 	}
121 	c.type_to_iqandstindex = htobe32(v |
122 	    V_FW_IQ_CMD_TYPE(FW_IQ_TYPE_FL_INT_CAP) |
123 	    V_FW_IQ_CMD_VIID(vi->viid) |
124 	    V_FW_IQ_CMD_IQANUD(X_UPDATEDELIVERY_INTERRUPT));
125 	c.iqdroprss_to_iqesize = htobe16(V_FW_IQ_CMD_IQPCIECH(vi->pi->tx_chan) |
126 	    F_FW_IQ_CMD_IQGTSMODE |
127 	    V_FW_IQ_CMD_IQINTCNTTHRESH(0) |
128 	    V_FW_IQ_CMD_IQESIZE(ilog2(IQ_ESIZE) - 4));
129 	c.iqsize = htobe16(vi->qsize_rxq);
130 	c.iqaddr = htobe64(nm_rxq->iq_ba);
131 	if (cong >= 0) {
132 		c.iqns_to_fl0congen = htobe32(F_FW_IQ_CMD_IQFLINTCONGEN |
133 		    V_FW_IQ_CMD_FL0CNGCHMAP(cong) | F_FW_IQ_CMD_FL0CONGCIF |
134 		    F_FW_IQ_CMD_FL0CONGEN);
135 	}
136 	c.iqns_to_fl0congen |=
137 	    htobe32(V_FW_IQ_CMD_FL0HOSTFCMODE(X_HOSTFCMODE_NONE) |
138 		F_FW_IQ_CMD_FL0FETCHRO | F_FW_IQ_CMD_FL0DATARO |
139 		(fl_pad ? F_FW_IQ_CMD_FL0PADEN : 0) |
140 		(black_hole == 2 ? F_FW_IQ_CMD_FL0PACKEN : 0));
141 	c.fl0dcaen_to_fl0cidxfthresh =
142 	    htobe16(V_FW_IQ_CMD_FL0FBMIN(chip_id(sc) <= CHELSIO_T5 ?
143 		X_FETCHBURSTMIN_128B : X_FETCHBURSTMIN_64B) |
144 		V_FW_IQ_CMD_FL0FBMAX(chip_id(sc) <= CHELSIO_T5 ?
145 		X_FETCHBURSTMAX_512B : X_FETCHBURSTMAX_256B));
146 	c.fl0size = htobe16(na->num_rx_desc / 8 + sp->spg_len / EQ_ESIZE);
147 	c.fl0addr = htobe64(nm_rxq->fl_ba);
148 
149 	rc = -t4_wr_mbox(sc, sc->mbox, &c, sizeof(c), &c);
150 	if (rc != 0) {
151 		device_printf(sc->dev,
152 		    "failed to create netmap ingress queue: %d\n", rc);
153 		return (rc);
154 	}
155 
156 	nm_rxq->iq_cidx = 0;
157 	MPASS(nm_rxq->iq_sidx == vi->qsize_rxq - sp->spg_len / IQ_ESIZE);
158 	nm_rxq->iq_gen = F_RSPD_GEN;
159 	nm_rxq->iq_cntxt_id = be16toh(c.iqid);
160 	nm_rxq->iq_abs_id = be16toh(c.physiqid);
161 	cntxt_id = nm_rxq->iq_cntxt_id - sc->sge.iq_start;
162 	if (cntxt_id >= sc->sge.niq) {
163 		panic ("%s: nm_rxq->iq_cntxt_id (%d) more than the max (%d)",
164 		    __func__, cntxt_id, sc->sge.niq - 1);
165 	}
166 	sc->sge.iqmap[cntxt_id] = (void *)nm_rxq;
167 
168 	nm_rxq->fl_cntxt_id = be16toh(c.fl0id);
169 	nm_rxq->fl_pidx = nm_rxq->fl_cidx = 0;
170 	MPASS(nm_rxq->fl_sidx == na->num_rx_desc);
171 	cntxt_id = nm_rxq->fl_cntxt_id - sc->sge.eq_start;
172 	if (cntxt_id >= sc->sge.neq) {
173 		panic("%s: nm_rxq->fl_cntxt_id (%d) more than the max (%d)",
174 		    __func__, cntxt_id, sc->sge.neq - 1);
175 	}
176 	sc->sge.eqmap[cntxt_id] = (void *)nm_rxq;
177 
178 	nm_rxq->fl_db_val = V_QID(nm_rxq->fl_cntxt_id) |
179 	    sc->chip_params->sge_fl_db;
180 
181 	if (chip_id(sc) >= CHELSIO_T5 && cong >= 0) {
182 		uint32_t param, val;
183 
184 		param = V_FW_PARAMS_MNEM(FW_PARAMS_MNEM_DMAQ) |
185 		    V_FW_PARAMS_PARAM_X(FW_PARAMS_PARAM_DMAQ_CONM_CTXT) |
186 		    V_FW_PARAMS_PARAM_YZ(nm_rxq->iq_cntxt_id);
187 		param = V_FW_PARAMS_MNEM(FW_PARAMS_MNEM_DMAQ) |
188 		    V_FW_PARAMS_PARAM_X(FW_PARAMS_PARAM_DMAQ_CONM_CTXT) |
189 		    V_FW_PARAMS_PARAM_YZ(nm_rxq->iq_cntxt_id);
190 		if (cong == 0)
191 			val = 1 << 19;
192 		else {
193 			val = 2 << 19;
194 			for (i = 0; i < 4; i++) {
195 				if (cong & (1 << i))
196 					val |= 1 << (i << 2);
197 			}
198 		}
199 
200 		rc = -t4_set_params(sc, sc->mbox, sc->pf, 0, 1, &param, &val);
201 		if (rc != 0) {
202 			/* report error but carry on */
203 			device_printf(sc->dev,
204 			    "failed to set congestion manager context for "
205 			    "ingress queue %d: %d\n", nm_rxq->iq_cntxt_id, rc);
206 		}
207 	}
208 
209 	t4_write_reg(sc, sc->sge_gts_reg,
210 	    V_INGRESSQID(nm_rxq->iq_cntxt_id) |
211 	    V_SEINTARM(V_QINTR_TIMER_IDX(holdoff_tmr_idx)));
212 
213 	return (rc);
214 }
215 
216 static int
217 free_nm_rxq_hwq(struct vi_info *vi, struct sge_nm_rxq *nm_rxq)
218 {
219 	struct adapter *sc = vi->pi->adapter;
220 	int rc;
221 
222 	rc = -t4_iq_free(sc, sc->mbox, sc->pf, 0, FW_IQ_TYPE_FL_INT_CAP,
223 	    nm_rxq->iq_cntxt_id, nm_rxq->fl_cntxt_id, 0xffff);
224 	if (rc != 0)
225 		device_printf(sc->dev, "%s: failed for iq %d, fl %d: %d\n",
226 		    __func__, nm_rxq->iq_cntxt_id, nm_rxq->fl_cntxt_id, rc);
227 	nm_rxq->iq_cntxt_id = INVALID_NM_RXQ_CNTXT_ID;
228 	return (rc);
229 }
230 
231 static int
232 alloc_nm_txq_hwq(struct vi_info *vi, struct sge_nm_txq *nm_txq)
233 {
234 	int rc, cntxt_id;
235 	size_t len;
236 	struct adapter *sc = vi->pi->adapter;
237 	struct netmap_adapter *na = NA(vi->ifp);
238 	struct fw_eq_eth_cmd c;
239 
240 	MPASS(na != NULL);
241 	MPASS(nm_txq->desc != NULL);
242 
243 	len = na->num_tx_desc * EQ_ESIZE + sc->params.sge.spg_len;
244 	bzero(nm_txq->desc, len);
245 
246 	bzero(&c, sizeof(c));
247 	c.op_to_vfn = htobe32(V_FW_CMD_OP(FW_EQ_ETH_CMD) | F_FW_CMD_REQUEST |
248 	    F_FW_CMD_WRITE | F_FW_CMD_EXEC | V_FW_EQ_ETH_CMD_PFN(sc->pf) |
249 	    V_FW_EQ_ETH_CMD_VFN(0));
250 	c.alloc_to_len16 = htobe32(F_FW_EQ_ETH_CMD_ALLOC |
251 	    F_FW_EQ_ETH_CMD_EQSTART | FW_LEN16(c));
252 	c.autoequiqe_to_viid = htobe32(F_FW_EQ_ETH_CMD_AUTOEQUIQE |
253 	    F_FW_EQ_ETH_CMD_AUTOEQUEQE | V_FW_EQ_ETH_CMD_VIID(vi->viid));
254 	c.fetchszm_to_iqid =
255 	    htobe32(V_FW_EQ_ETH_CMD_HOSTFCMODE(X_HOSTFCMODE_NONE) |
256 		V_FW_EQ_ETH_CMD_PCIECHN(vi->pi->tx_chan) | F_FW_EQ_ETH_CMD_FETCHRO |
257 		V_FW_EQ_ETH_CMD_IQID(sc->sge.nm_rxq[nm_txq->iqidx].iq_cntxt_id));
258 	c.dcaen_to_eqsize = htobe32(V_FW_EQ_ETH_CMD_FBMIN(X_FETCHBURSTMIN_64B) |
259 		      V_FW_EQ_ETH_CMD_FBMAX(X_FETCHBURSTMAX_512B) |
260 		      V_FW_EQ_ETH_CMD_EQSIZE(len / EQ_ESIZE));
261 	c.eqaddr = htobe64(nm_txq->ba);
262 
263 	rc = -t4_wr_mbox(sc, sc->mbox, &c, sizeof(c), &c);
264 	if (rc != 0) {
265 		device_printf(vi->dev,
266 		    "failed to create netmap egress queue: %d\n", rc);
267 		return (rc);
268 	}
269 
270 	nm_txq->cntxt_id = G_FW_EQ_ETH_CMD_EQID(be32toh(c.eqid_pkd));
271 	cntxt_id = nm_txq->cntxt_id - sc->sge.eq_start;
272 	if (cntxt_id >= sc->sge.neq)
273 	    panic("%s: nm_txq->cntxt_id (%d) more than the max (%d)", __func__,
274 		cntxt_id, sc->sge.neq - 1);
275 	sc->sge.eqmap[cntxt_id] = (void *)nm_txq;
276 
277 	nm_txq->pidx = nm_txq->cidx = 0;
278 	MPASS(nm_txq->sidx == na->num_tx_desc);
279 	nm_txq->equiqidx = nm_txq->equeqidx = nm_txq->dbidx = 0;
280 
281 	nm_txq->doorbells = sc->doorbells;
282 	if (isset(&nm_txq->doorbells, DOORBELL_UDB) ||
283 	    isset(&nm_txq->doorbells, DOORBELL_UDBWC) ||
284 	    isset(&nm_txq->doorbells, DOORBELL_WCWR)) {
285 		uint32_t s_qpp = sc->params.sge.eq_s_qpp;
286 		uint32_t mask = (1 << s_qpp) - 1;
287 		volatile uint8_t *udb;
288 
289 		udb = sc->udbs_base + UDBS_DB_OFFSET;
290 		udb += (nm_txq->cntxt_id >> s_qpp) << PAGE_SHIFT;
291 		nm_txq->udb_qid = nm_txq->cntxt_id & mask;
292 		if (nm_txq->udb_qid >= PAGE_SIZE / UDBS_SEG_SIZE)
293 	    		clrbit(&nm_txq->doorbells, DOORBELL_WCWR);
294 		else {
295 			udb += nm_txq->udb_qid << UDBS_SEG_SHIFT;
296 			nm_txq->udb_qid = 0;
297 		}
298 		nm_txq->udb = (volatile void *)udb;
299 	}
300 
301 	return (rc);
302 }
303 
304 static int
305 free_nm_txq_hwq(struct vi_info *vi, struct sge_nm_txq *nm_txq)
306 {
307 	struct adapter *sc = vi->pi->adapter;
308 	int rc;
309 
310 	rc = -t4_eth_eq_free(sc, sc->mbox, sc->pf, 0, nm_txq->cntxt_id);
311 	if (rc != 0)
312 		device_printf(sc->dev, "%s: failed for eq %d: %d\n", __func__,
313 		    nm_txq->cntxt_id, rc);
314 	nm_txq->cntxt_id = INVALID_NM_TXQ_CNTXT_ID;
315 	return (rc);
316 }
317 
318 static int
319 cxgbe_netmap_on(struct adapter *sc, struct vi_info *vi, struct ifnet *ifp,
320     struct netmap_adapter *na)
321 {
322 	struct netmap_slot *slot;
323 	struct netmap_kring *kring;
324 	struct sge_nm_rxq *nm_rxq;
325 	struct sge_nm_txq *nm_txq;
326 	int rc, i, j, hwidx;
327 	struct hw_buf_info *hwb;
328 
329 	ASSERT_SYNCHRONIZED_OP(sc);
330 
331 	if ((vi->flags & VI_INIT_DONE) == 0 ||
332 	    (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
333 		return (EAGAIN);
334 
335 	hwb = &sc->sge.hw_buf_info[0];
336 	for (i = 0; i < SGE_FLBUF_SIZES; i++, hwb++) {
337 		if (hwb->size == NETMAP_BUF_SIZE(na))
338 			break;
339 	}
340 	if (i >= SGE_FLBUF_SIZES) {
341 		if_printf(ifp, "no hwidx for netmap buffer size %d.\n",
342 		    NETMAP_BUF_SIZE(na));
343 		return (ENXIO);
344 	}
345 	hwidx = i;
346 
347 	/* Must set caps before calling netmap_reset */
348 	nm_set_native_flags(na);
349 
350 	for_each_nm_rxq(vi, i, nm_rxq) {
351 		struct irq *irq = &sc->irq[vi->first_intr + i];
352 
353 		kring = &na->rx_rings[nm_rxq->nid];
354 		if (!nm_kring_pending_on(kring) ||
355 		    nm_rxq->iq_cntxt_id != INVALID_NM_RXQ_CNTXT_ID)
356 			continue;
357 
358 		alloc_nm_rxq_hwq(vi, nm_rxq, tnl_cong(vi->pi, nm_cong_drop));
359 		nm_rxq->fl_hwidx = hwidx;
360 		slot = netmap_reset(na, NR_RX, i, 0);
361 		MPASS(slot != NULL);	/* XXXNM: error check, not assert */
362 
363 		/* We deal with 8 bufs at a time */
364 		MPASS((na->num_rx_desc & 7) == 0);
365 		MPASS(na->num_rx_desc == nm_rxq->fl_sidx);
366 		for (j = 0; j < nm_rxq->fl_sidx; j++) {
367 			uint64_t ba;
368 
369 			PNMB(na, &slot[j], &ba);
370 			MPASS(ba != 0);
371 			nm_rxq->fl_desc[j] = htobe64(ba | hwidx);
372 		}
373 		j = nm_rxq->fl_pidx = nm_rxq->fl_sidx - 8;
374 		MPASS((j & 7) == 0);
375 		j /= 8;	/* driver pidx to hardware pidx */
376 		wmb();
377 		t4_write_reg(sc, sc->sge_kdoorbell_reg,
378 		    nm_rxq->fl_db_val | V_PIDX(j));
379 
380 		atomic_cmpset_int(&irq->nm_state, NM_OFF, NM_ON);
381 	}
382 
383 	for_each_nm_txq(vi, i, nm_txq) {
384 		kring = &na->tx_rings[nm_txq->nid];
385 		if (!nm_kring_pending_on(kring) ||
386 		    nm_txq->cntxt_id != INVALID_NM_TXQ_CNTXT_ID)
387 			continue;
388 
389 		alloc_nm_txq_hwq(vi, nm_txq);
390 		slot = netmap_reset(na, NR_TX, i, 0);
391 		MPASS(slot != NULL);	/* XXXNM: error check, not assert */
392 	}
393 
394 	if (vi->nm_rss == NULL) {
395 		vi->nm_rss = malloc(vi->rss_size * sizeof(uint16_t), M_CXGBE,
396 		    M_ZERO | M_WAITOK);
397 	}
398 	for (i = 0; i < vi->rss_size;) {
399 		for_each_nm_rxq(vi, j, nm_rxq) {
400 			vi->nm_rss[i++] = nm_rxq->iq_abs_id;
401 			if (i == vi->rss_size)
402 				break;
403 		}
404 	}
405 	rc = -t4_config_rss_range(sc, sc->mbox, vi->viid, 0, vi->rss_size,
406 	    vi->nm_rss, vi->rss_size);
407 	if (rc != 0)
408 		if_printf(ifp, "netmap rss_config failed: %d\n", rc);
409 
410 	return (rc);
411 }
412 
413 static int
414 cxgbe_netmap_off(struct adapter *sc, struct vi_info *vi, struct ifnet *ifp,
415     struct netmap_adapter *na)
416 {
417 	struct netmap_kring *kring;
418 	int rc, i;
419 	struct sge_nm_txq *nm_txq;
420 	struct sge_nm_rxq *nm_rxq;
421 
422 	ASSERT_SYNCHRONIZED_OP(sc);
423 
424 	if ((vi->flags & VI_INIT_DONE) == 0)
425 		return (0);
426 
427 	rc = -t4_config_rss_range(sc, sc->mbox, vi->viid, 0, vi->rss_size,
428 	    vi->rss, vi->rss_size);
429 	if (rc != 0)
430 		if_printf(ifp, "failed to restore RSS config: %d\n", rc);
431 	nm_clear_native_flags(na);
432 
433 	for_each_nm_txq(vi, i, nm_txq) {
434 		struct sge_qstat *spg = (void *)&nm_txq->desc[nm_txq->sidx];
435 
436 		kring = &na->tx_rings[nm_txq->nid];
437 		if (!nm_kring_pending_off(kring) ||
438 		    nm_txq->cntxt_id == INVALID_NM_TXQ_CNTXT_ID)
439 			continue;
440 
441 		/* Wait for hw pidx to catch up ... */
442 		while (be16toh(nm_txq->pidx) != spg->pidx)
443 			pause("nmpidx", 1);
444 
445 		/* ... and then for the cidx. */
446 		while (spg->pidx != spg->cidx)
447 			pause("nmcidx", 1);
448 
449 		free_nm_txq_hwq(vi, nm_txq);
450 	}
451 	for_each_nm_rxq(vi, i, nm_rxq) {
452 		struct irq *irq = &sc->irq[vi->first_intr + i];
453 
454 		kring = &na->rx_rings[nm_rxq->nid];
455 		if (!nm_kring_pending_off(kring) ||
456 		    nm_rxq->iq_cntxt_id == INVALID_NM_RXQ_CNTXT_ID)
457 			continue;
458 
459 		while (!atomic_cmpset_int(&irq->nm_state, NM_ON, NM_OFF))
460 			pause("nmst", 1);
461 
462 		free_nm_rxq_hwq(vi, nm_rxq);
463 	}
464 
465 	return (rc);
466 }
467 
468 static int
469 cxgbe_netmap_reg(struct netmap_adapter *na, int on)
470 {
471 	struct ifnet *ifp = na->ifp;
472 	struct vi_info *vi = ifp->if_softc;
473 	struct adapter *sc = vi->pi->adapter;
474 	int rc;
475 
476 	rc = begin_synchronized_op(sc, vi, SLEEP_OK | INTR_OK, "t4nmreg");
477 	if (rc != 0)
478 		return (rc);
479 	if (on)
480 		rc = cxgbe_netmap_on(sc, vi, ifp, na);
481 	else
482 		rc = cxgbe_netmap_off(sc, vi, ifp, na);
483 	end_synchronized_op(sc, 0);
484 
485 	return (rc);
486 }
487 
488 /* How many packets can a single type1 WR carry in n descriptors */
489 static inline int
490 ndesc_to_npkt(const int n)
491 {
492 
493 	MPASS(n > 0 && n <= SGE_MAX_WR_NDESC);
494 
495 	return (n * 2 - 1);
496 }
497 #define MAX_NPKT_IN_TYPE1_WR	(ndesc_to_npkt(SGE_MAX_WR_NDESC))
498 
499 /* Space (in descriptors) needed for a type1 WR that carries n packets */
500 static inline int
501 npkt_to_ndesc(const int n)
502 {
503 
504 	MPASS(n > 0 && n <= MAX_NPKT_IN_TYPE1_WR);
505 
506 	return ((n + 2) / 2);
507 }
508 
509 /* Space (in 16B units) needed for a type1 WR that carries n packets */
510 static inline int
511 npkt_to_len16(const int n)
512 {
513 
514 	MPASS(n > 0 && n <= MAX_NPKT_IN_TYPE1_WR);
515 
516 	return (n * 2 + 1);
517 }
518 
519 #define NMIDXDIFF(q, idx) IDXDIFF((q)->pidx, (q)->idx, (q)->sidx)
520 
521 static void
522 ring_nm_txq_db(struct adapter *sc, struct sge_nm_txq *nm_txq)
523 {
524 	int n;
525 	u_int db = nm_txq->doorbells;
526 
527 	MPASS(nm_txq->pidx != nm_txq->dbidx);
528 
529 	n = NMIDXDIFF(nm_txq, dbidx);
530 	if (n > 1)
531 		clrbit(&db, DOORBELL_WCWR);
532 	wmb();
533 
534 	switch (ffs(db) - 1) {
535 	case DOORBELL_UDB:
536 		*nm_txq->udb = htole32(V_QID(nm_txq->udb_qid) | V_PIDX(n));
537 		break;
538 
539 	case DOORBELL_WCWR: {
540 		volatile uint64_t *dst, *src;
541 
542 		/*
543 		 * Queues whose 128B doorbell segment fits in the page do not
544 		 * use relative qid (udb_qid is always 0).  Only queues with
545 		 * doorbell segments can do WCWR.
546 		 */
547 		KASSERT(nm_txq->udb_qid == 0 && n == 1,
548 		    ("%s: inappropriate doorbell (0x%x, %d, %d) for nm_txq %p",
549 		    __func__, nm_txq->doorbells, n, nm_txq->pidx, nm_txq));
550 
551 		dst = (volatile void *)((uintptr_t)nm_txq->udb +
552 		    UDBS_WR_OFFSET - UDBS_DB_OFFSET);
553 		src = (void *)&nm_txq->desc[nm_txq->dbidx];
554 		while (src != (void *)&nm_txq->desc[nm_txq->dbidx + 1])
555 			*dst++ = *src++;
556 		wmb();
557 		break;
558 	}
559 
560 	case DOORBELL_UDBWC:
561 		*nm_txq->udb = htole32(V_QID(nm_txq->udb_qid) | V_PIDX(n));
562 		wmb();
563 		break;
564 
565 	case DOORBELL_KDB:
566 		t4_write_reg(sc, sc->sge_kdoorbell_reg,
567 		    V_QID(nm_txq->cntxt_id) | V_PIDX(n));
568 		break;
569 	}
570 	nm_txq->dbidx = nm_txq->pidx;
571 }
572 
573 int lazy_tx_credit_flush = 1;
574 
575 /*
576  * Write work requests to send 'npkt' frames and ring the doorbell to send them
577  * on their way.  No need to check for wraparound.
578  */
579 static void
580 cxgbe_nm_tx(struct adapter *sc, struct sge_nm_txq *nm_txq,
581     struct netmap_kring *kring, int npkt, int npkt_remaining, int txcsum)
582 {
583 	struct netmap_ring *ring = kring->ring;
584 	struct netmap_slot *slot;
585 	const u_int lim = kring->nkr_num_slots - 1;
586 	struct fw_eth_tx_pkts_wr *wr = (void *)&nm_txq->desc[nm_txq->pidx];
587 	uint16_t len;
588 	uint64_t ba;
589 	struct cpl_tx_pkt_core *cpl;
590 	struct ulptx_sgl *usgl;
591 	int i, n;
592 
593 	while (npkt) {
594 		n = min(npkt, MAX_NPKT_IN_TYPE1_WR);
595 		len = 0;
596 
597 		wr = (void *)&nm_txq->desc[nm_txq->pidx];
598 		wr->op_pkd = htobe32(V_FW_WR_OP(FW_ETH_TX_PKTS_WR));
599 		wr->equiq_to_len16 = htobe32(V_FW_WR_LEN16(npkt_to_len16(n)));
600 		wr->npkt = n;
601 		wr->r3 = 0;
602 		wr->type = 1;
603 		cpl = (void *)(wr + 1);
604 
605 		for (i = 0; i < n; i++) {
606 			slot = &ring->slot[kring->nr_hwcur];
607 			PNMB(kring->na, slot, &ba);
608 			MPASS(ba != 0);
609 
610 			cpl->ctrl0 = nm_txq->cpl_ctrl0;
611 			cpl->pack = 0;
612 			cpl->len = htobe16(slot->len);
613 			/*
614 			 * netmap(4) says "netmap does not use features such as
615 			 * checksum offloading, TCP segmentation offloading,
616 			 * encryption, VLAN encapsulation/decapsulation, etc."
617 			 *
618 			 * So the ncxl interfaces have tx hardware checksumming
619 			 * disabled by default.  But you can override netmap by
620 			 * enabling IFCAP_TXCSUM on the interface manully.
621 			 */
622 			cpl->ctrl1 = txcsum ? 0 :
623 			    htobe64(F_TXPKT_IPCSUM_DIS | F_TXPKT_L4CSUM_DIS);
624 
625 			usgl = (void *)(cpl + 1);
626 			usgl->cmd_nsge = htobe32(V_ULPTX_CMD(ULP_TX_SC_DSGL) |
627 			    V_ULPTX_NSGE(1));
628 			usgl->len0 = htobe32(slot->len);
629 			usgl->addr0 = htobe64(ba);
630 
631 			slot->flags &= ~(NS_REPORT | NS_BUF_CHANGED);
632 			cpl = (void *)(usgl + 1);
633 			MPASS(slot->len + len <= UINT16_MAX);
634 			len += slot->len;
635 			kring->nr_hwcur = nm_next(kring->nr_hwcur, lim);
636 		}
637 		wr->plen = htobe16(len);
638 
639 		npkt -= n;
640 		nm_txq->pidx += npkt_to_ndesc(n);
641 		MPASS(nm_txq->pidx <= nm_txq->sidx);
642 		if (__predict_false(nm_txq->pidx == nm_txq->sidx)) {
643 			/*
644 			 * This routine doesn't know how to write WRs that wrap
645 			 * around.  Make sure it wasn't asked to.
646 			 */
647 			MPASS(npkt == 0);
648 			nm_txq->pidx = 0;
649 		}
650 
651 		if (npkt == 0 && npkt_remaining == 0) {
652 			/* All done. */
653 			if (lazy_tx_credit_flush == 0) {
654 				wr->equiq_to_len16 |= htobe32(F_FW_WR_EQUEQ |
655 				    F_FW_WR_EQUIQ);
656 				nm_txq->equeqidx = nm_txq->pidx;
657 				nm_txq->equiqidx = nm_txq->pidx;
658 			}
659 			ring_nm_txq_db(sc, nm_txq);
660 			return;
661 		}
662 
663 		if (NMIDXDIFF(nm_txq, equiqidx) >= nm_txq->sidx / 2) {
664 			wr->equiq_to_len16 |= htobe32(F_FW_WR_EQUEQ |
665 			    F_FW_WR_EQUIQ);
666 			nm_txq->equeqidx = nm_txq->pidx;
667 			nm_txq->equiqidx = nm_txq->pidx;
668 		} else if (NMIDXDIFF(nm_txq, equeqidx) >= 64) {
669 			wr->equiq_to_len16 |= htobe32(F_FW_WR_EQUEQ);
670 			nm_txq->equeqidx = nm_txq->pidx;
671 		}
672 		if (NMIDXDIFF(nm_txq, dbidx) >= 2 * SGE_MAX_WR_NDESC)
673 			ring_nm_txq_db(sc, nm_txq);
674 	}
675 
676 	/* Will get called again. */
677 	MPASS(npkt_remaining);
678 }
679 
680 /* How many contiguous free descriptors starting at pidx */
681 static inline int
682 contiguous_ndesc_available(struct sge_nm_txq *nm_txq)
683 {
684 
685 	if (nm_txq->cidx > nm_txq->pidx)
686 		return (nm_txq->cidx - nm_txq->pidx - 1);
687 	else if (nm_txq->cidx > 0)
688 		return (nm_txq->sidx - nm_txq->pidx);
689 	else
690 		return (nm_txq->sidx - nm_txq->pidx - 1);
691 }
692 
693 static int
694 reclaim_nm_tx_desc(struct sge_nm_txq *nm_txq)
695 {
696 	struct sge_qstat *spg = (void *)&nm_txq->desc[nm_txq->sidx];
697 	uint16_t hw_cidx = spg->cidx;	/* snapshot */
698 	struct fw_eth_tx_pkts_wr *wr;
699 	int n = 0;
700 
701 	hw_cidx = be16toh(hw_cidx);
702 
703 	while (nm_txq->cidx != hw_cidx) {
704 		wr = (void *)&nm_txq->desc[nm_txq->cidx];
705 
706 		MPASS(wr->op_pkd == htobe32(V_FW_WR_OP(FW_ETH_TX_PKTS_WR)));
707 		MPASS(wr->type == 1);
708 		MPASS(wr->npkt > 0 && wr->npkt <= MAX_NPKT_IN_TYPE1_WR);
709 
710 		n += wr->npkt;
711 		nm_txq->cidx += npkt_to_ndesc(wr->npkt);
712 
713 		/*
714 		 * We never sent a WR that wrapped around so the credits coming
715 		 * back, WR by WR, should never cause the cidx to wrap around
716 		 * either.
717 		 */
718 		MPASS(nm_txq->cidx <= nm_txq->sidx);
719 		if (__predict_false(nm_txq->cidx == nm_txq->sidx))
720 			nm_txq->cidx = 0;
721 	}
722 
723 	return (n);
724 }
725 
726 static int
727 cxgbe_netmap_txsync(struct netmap_kring *kring, int flags)
728 {
729 	struct netmap_adapter *na = kring->na;
730 	struct ifnet *ifp = na->ifp;
731 	struct vi_info *vi = ifp->if_softc;
732 	struct adapter *sc = vi->pi->adapter;
733 	struct sge_nm_txq *nm_txq = &sc->sge.nm_txq[vi->first_nm_txq + kring->ring_id];
734 	const u_int head = kring->rhead;
735 	u_int reclaimed = 0;
736 	int n, d, npkt_remaining, ndesc_remaining, txcsum;
737 
738 	/*
739 	 * Tx was at kring->nr_hwcur last time around and now we need to advance
740 	 * to kring->rhead.  Note that the driver's pidx moves independent of
741 	 * netmap's kring->nr_hwcur (pidx counts descriptors and the relation
742 	 * between descriptors and frames isn't 1:1).
743 	 */
744 
745 	npkt_remaining = head >= kring->nr_hwcur ? head - kring->nr_hwcur :
746 	    kring->nkr_num_slots - kring->nr_hwcur + head;
747 	txcsum = ifp->if_capenable & (IFCAP_TXCSUM | IFCAP_TXCSUM_IPV6);
748 	while (npkt_remaining) {
749 		reclaimed += reclaim_nm_tx_desc(nm_txq);
750 		ndesc_remaining = contiguous_ndesc_available(nm_txq);
751 		/* Can't run out of descriptors with packets still remaining */
752 		MPASS(ndesc_remaining > 0);
753 
754 		/* # of desc needed to tx all remaining packets */
755 		d = (npkt_remaining / MAX_NPKT_IN_TYPE1_WR) * SGE_MAX_WR_NDESC;
756 		if (npkt_remaining % MAX_NPKT_IN_TYPE1_WR)
757 			d += npkt_to_ndesc(npkt_remaining % MAX_NPKT_IN_TYPE1_WR);
758 
759 		if (d <= ndesc_remaining)
760 			n = npkt_remaining;
761 		else {
762 			/* Can't send all, calculate how many can be sent */
763 			n = (ndesc_remaining / SGE_MAX_WR_NDESC) *
764 			    MAX_NPKT_IN_TYPE1_WR;
765 			if (ndesc_remaining % SGE_MAX_WR_NDESC)
766 				n += ndesc_to_npkt(ndesc_remaining % SGE_MAX_WR_NDESC);
767 		}
768 
769 		/* Send n packets and update nm_txq->pidx and kring->nr_hwcur */
770 		npkt_remaining -= n;
771 		cxgbe_nm_tx(sc, nm_txq, kring, n, npkt_remaining, txcsum);
772 	}
773 	MPASS(npkt_remaining == 0);
774 	MPASS(kring->nr_hwcur == head);
775 	MPASS(nm_txq->dbidx == nm_txq->pidx);
776 
777 	/*
778 	 * Second part: reclaim buffers for completed transmissions.
779 	 */
780 	if (reclaimed || flags & NAF_FORCE_RECLAIM || nm_kr_txempty(kring)) {
781 		reclaimed += reclaim_nm_tx_desc(nm_txq);
782 		kring->nr_hwtail += reclaimed;
783 		if (kring->nr_hwtail >= kring->nkr_num_slots)
784 			kring->nr_hwtail -= kring->nkr_num_slots;
785 	}
786 
787 	return (0);
788 }
789 
790 static int
791 cxgbe_netmap_rxsync(struct netmap_kring *kring, int flags)
792 {
793 	struct netmap_adapter *na = kring->na;
794 	struct netmap_ring *ring = kring->ring;
795 	struct ifnet *ifp = na->ifp;
796 	struct vi_info *vi = ifp->if_softc;
797 	struct adapter *sc = vi->pi->adapter;
798 	struct sge_nm_rxq *nm_rxq = &sc->sge.nm_rxq[vi->first_nm_rxq + kring->ring_id];
799 	u_int const head = kring->rhead;
800 	u_int n;
801 	int force_update = (flags & NAF_FORCE_READ) || kring->nr_kflags & NKR_PENDINTR;
802 
803 	if (black_hole)
804 		return (0);	/* No updates ever. */
805 
806 	if (netmap_no_pendintr || force_update) {
807 		kring->nr_hwtail = atomic_load_acq_32(&nm_rxq->fl_cidx);
808 		kring->nr_kflags &= ~NKR_PENDINTR;
809 	}
810 
811 	/* Userspace done with buffers from kring->nr_hwcur to head */
812 	n = head >= kring->nr_hwcur ? head - kring->nr_hwcur :
813 	    kring->nkr_num_slots - kring->nr_hwcur + head;
814 	n &= ~7U;
815 	if (n > 0) {
816 		u_int fl_pidx = nm_rxq->fl_pidx;
817 		struct netmap_slot *slot = &ring->slot[fl_pidx];
818 		uint64_t ba;
819 		int i, dbinc = 0, hwidx = nm_rxq->fl_hwidx;
820 
821 		/*
822 		 * We always deal with 8 buffers at a time.  We must have
823 		 * stopped at an 8B boundary (fl_pidx) last time around and we
824 		 * must have a multiple of 8B buffers to give to the freelist.
825 		 */
826 		MPASS((fl_pidx & 7) == 0);
827 		MPASS((n & 7) == 0);
828 
829 		IDXINCR(kring->nr_hwcur, n, kring->nkr_num_slots);
830 		IDXINCR(nm_rxq->fl_pidx, n, nm_rxq->fl_sidx);
831 
832 		while (n > 0) {
833 			for (i = 0; i < 8; i++, fl_pidx++, slot++) {
834 				PNMB(na, slot, &ba);
835 				MPASS(ba != 0);
836 				nm_rxq->fl_desc[fl_pidx] = htobe64(ba | hwidx);
837 				slot->flags &= ~NS_BUF_CHANGED;
838 				MPASS(fl_pidx <= nm_rxq->fl_sidx);
839 			}
840 			n -= 8;
841 			if (fl_pidx == nm_rxq->fl_sidx) {
842 				fl_pidx = 0;
843 				slot = &ring->slot[0];
844 			}
845 			if (++dbinc == 8 && n >= 32) {
846 				wmb();
847 				t4_write_reg(sc, sc->sge_kdoorbell_reg,
848 				    nm_rxq->fl_db_val | V_PIDX(dbinc));
849 				dbinc = 0;
850 			}
851 		}
852 		MPASS(nm_rxq->fl_pidx == fl_pidx);
853 
854 		if (dbinc > 0) {
855 			wmb();
856 			t4_write_reg(sc, sc->sge_kdoorbell_reg,
857 			    nm_rxq->fl_db_val | V_PIDX(dbinc));
858 		}
859 	}
860 
861 	return (0);
862 }
863 
864 void
865 cxgbe_nm_attach(struct vi_info *vi)
866 {
867 	struct port_info *pi;
868 	struct adapter *sc;
869 	struct netmap_adapter na;
870 
871 	MPASS(vi->nnmrxq > 0);
872 	MPASS(vi->ifp != NULL);
873 
874 	pi = vi->pi;
875 	sc = pi->adapter;
876 
877 	bzero(&na, sizeof(na));
878 
879 	na.ifp = vi->ifp;
880 	na.na_flags = NAF_BDG_MAYSLEEP;
881 
882 	/* Netmap doesn't know about the space reserved for the status page. */
883 	na.num_tx_desc = vi->qsize_txq - sc->params.sge.spg_len / EQ_ESIZE;
884 
885 	/*
886 	 * The freelist's cidx/pidx drives netmap's rx cidx/pidx.  So
887 	 * num_rx_desc is based on the number of buffers that can be held in the
888 	 * freelist, and not the number of entries in the iq.  (These two are
889 	 * not exactly the same due to the space taken up by the status page).
890 	 */
891 	na.num_rx_desc = rounddown(vi->qsize_rxq, 8);
892 	na.nm_txsync = cxgbe_netmap_txsync;
893 	na.nm_rxsync = cxgbe_netmap_rxsync;
894 	na.nm_register = cxgbe_netmap_reg;
895 	na.num_tx_rings = vi->nnmtxq;
896 	na.num_rx_rings = vi->nnmrxq;
897 	netmap_attach(&na);
898 }
899 
900 void
901 cxgbe_nm_detach(struct vi_info *vi)
902 {
903 
904 	MPASS(vi->nnmrxq > 0);
905 	MPASS(vi->ifp != NULL);
906 
907 	netmap_detach(vi->ifp);
908 }
909 
910 static inline const void *
911 unwrap_nm_fw6_msg(const struct cpl_fw6_msg *cpl)
912 {
913 
914 	MPASS(cpl->type == FW_TYPE_RSSCPL || cpl->type == FW6_TYPE_RSSCPL);
915 
916 	/* data[0] is RSS header */
917 	return (&cpl->data[1]);
918 }
919 
920 static void
921 handle_nm_sge_egr_update(struct adapter *sc, struct ifnet *ifp,
922     const struct cpl_sge_egr_update *egr)
923 {
924 	uint32_t oq;
925 	struct sge_nm_txq *nm_txq;
926 
927 	oq = be32toh(egr->opcode_qid);
928 	MPASS(G_CPL_OPCODE(oq) == CPL_SGE_EGR_UPDATE);
929 	nm_txq = (void *)sc->sge.eqmap[G_EGR_QID(oq) - sc->sge.eq_start];
930 
931 	netmap_tx_irq(ifp, nm_txq->nid);
932 }
933 
934 void
935 t4_nm_intr(void *arg)
936 {
937 	struct sge_nm_rxq *nm_rxq = arg;
938 	struct vi_info *vi = nm_rxq->vi;
939 	struct adapter *sc = vi->pi->adapter;
940 	struct ifnet *ifp = vi->ifp;
941 	struct netmap_adapter *na = NA(ifp);
942 	struct netmap_kring *kring = &na->rx_rings[nm_rxq->nid];
943 	struct netmap_ring *ring = kring->ring;
944 	struct iq_desc *d = &nm_rxq->iq_desc[nm_rxq->iq_cidx];
945 	const void *cpl;
946 	uint32_t lq;
947 	u_int n = 0, work = 0;
948 	uint8_t opcode;
949 	uint32_t fl_cidx = atomic_load_acq_32(&nm_rxq->fl_cidx);
950 	u_int fl_credits = fl_cidx & 7;
951 
952 	while ((d->rsp.u.type_gen & F_RSPD_GEN) == nm_rxq->iq_gen) {
953 
954 		rmb();
955 
956 		lq = be32toh(d->rsp.pldbuflen_qid);
957 		opcode = d->rss.opcode;
958 		cpl = &d->cpl[0];
959 
960 		switch (G_RSPD_TYPE(d->rsp.u.type_gen)) {
961 		case X_RSPD_TYPE_FLBUF:
962 			if (black_hole != 2) {
963 				/* No buffer packing so new buf every time */
964 				MPASS(lq & F_RSPD_NEWBUF);
965 			}
966 
967 			/* fall through */
968 
969 		case X_RSPD_TYPE_CPL:
970 			MPASS(opcode < NUM_CPL_CMDS);
971 
972 			switch (opcode) {
973 			case CPL_FW4_MSG:
974 			case CPL_FW6_MSG:
975 				cpl = unwrap_nm_fw6_msg(cpl);
976 				/* fall through */
977 			case CPL_SGE_EGR_UPDATE:
978 				handle_nm_sge_egr_update(sc, ifp, cpl);
979 				break;
980 			case CPL_RX_PKT:
981 				ring->slot[fl_cidx].len = G_RSPD_LEN(lq) -
982 				    sc->params.sge.fl_pktshift;
983 				ring->slot[fl_cidx].flags = kring->nkr_slot_flags;
984 				fl_cidx += (lq & F_RSPD_NEWBUF) ? 1 : 0;
985 				fl_credits += (lq & F_RSPD_NEWBUF) ? 1 : 0;
986 				if (__predict_false(fl_cidx == nm_rxq->fl_sidx))
987 					fl_cidx = 0;
988 				break;
989 			default:
990 				panic("%s: unexpected opcode 0x%x on nm_rxq %p",
991 				    __func__, opcode, nm_rxq);
992 			}
993 			break;
994 
995 		case X_RSPD_TYPE_INTR:
996 			/* Not equipped to handle forwarded interrupts. */
997 			panic("%s: netmap queue received interrupt for iq %u\n",
998 			    __func__, lq);
999 
1000 		default:
1001 			panic("%s: illegal response type %d on nm_rxq %p",
1002 			    __func__, G_RSPD_TYPE(d->rsp.u.type_gen), nm_rxq);
1003 		}
1004 
1005 		d++;
1006 		if (__predict_false(++nm_rxq->iq_cidx == nm_rxq->iq_sidx)) {
1007 			nm_rxq->iq_cidx = 0;
1008 			d = &nm_rxq->iq_desc[0];
1009 			nm_rxq->iq_gen ^= F_RSPD_GEN;
1010 		}
1011 
1012 		if (__predict_false(++n == rx_ndesc)) {
1013 			atomic_store_rel_32(&nm_rxq->fl_cidx, fl_cidx);
1014 			if (black_hole && fl_credits >= 8) {
1015 				fl_credits /= 8;
1016 				IDXINCR(nm_rxq->fl_pidx, fl_credits * 8,
1017 				    nm_rxq->fl_sidx);
1018 				t4_write_reg(sc, sc->sge_kdoorbell_reg,
1019 				    nm_rxq->fl_db_val | V_PIDX(fl_credits));
1020 				fl_credits = fl_cidx & 7;
1021 			} else if (!black_hole) {
1022 				netmap_rx_irq(ifp, nm_rxq->nid, &work);
1023 				MPASS(work != 0);
1024 			}
1025 			t4_write_reg(sc, sc->sge_gts_reg,
1026 			    V_CIDXINC(n) | V_INGRESSQID(nm_rxq->iq_cntxt_id) |
1027 			    V_SEINTARM(V_QINTR_TIMER_IDX(X_TIMERREG_UPDATE_CIDX)));
1028 			n = 0;
1029 		}
1030 	}
1031 
1032 	atomic_store_rel_32(&nm_rxq->fl_cidx, fl_cidx);
1033 	if (black_hole) {
1034 		fl_credits /= 8;
1035 		IDXINCR(nm_rxq->fl_pidx, fl_credits * 8, nm_rxq->fl_sidx);
1036 		t4_write_reg(sc, sc->sge_kdoorbell_reg,
1037 		    nm_rxq->fl_db_val | V_PIDX(fl_credits));
1038 	} else
1039 		netmap_rx_irq(ifp, nm_rxq->nid, &work);
1040 
1041 	t4_write_reg(sc, sc->sge_gts_reg, V_CIDXINC(n) |
1042 	    V_INGRESSQID((u32)nm_rxq->iq_cntxt_id) |
1043 	    V_SEINTARM(V_QINTR_TIMER_IDX(holdoff_tmr_idx)));
1044 }
1045 #endif
1046