xref: /freebsd-11-stable/sys/dev/cxgbe/t4_netmap.c (revision 17de9e9a183c63970fdbe7d9fbf51b999f36a22c)
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_RDTUN, &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 holdoff_tmr_idx = 2;
74 SYSCTL_INT(_hw_cxgbe, OID_AUTO, nm_holdoff_tmr_idx, CTLFLAG_RWTUN,
75     &holdoff_tmr_idx, 0, "Holdoff timer index for netmap rx queues.");
76 
77 /*
78  * Congestion drops.
79  * -1: no congestion feedback (not recommended).
80  *  0: backpressure the channel instead of dropping packets right away.
81  *  1: no backpressure, drop packets for the congested queue immediately.
82  */
83 static int nm_cong_drop = 1;
84 SYSCTL_INT(_hw_cxgbe, OID_AUTO, nm_cong_drop, CTLFLAG_RDTUN,
85     &nm_cong_drop, 0,
86     "Congestion control for netmap rx queues (0 = backpressure, 1 = drop");
87 
88 static int
alloc_nm_rxq_hwq(struct vi_info * vi,struct sge_nm_rxq * nm_rxq,int cong)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 	MPASS(!forwarding_intr_to_fwq(sc));
112 	KASSERT(nm_rxq->intr_idx < sc->intr_count,
113 	    ("%s: invalid direct intr_idx %d", __func__, nm_rxq->intr_idx));
114 	v = V_FW_IQ_CMD_IQANDSTINDEX(nm_rxq->intr_idx);
115 	c.type_to_iqandstindex = htobe32(v |
116 	    V_FW_IQ_CMD_TYPE(FW_IQ_TYPE_FL_INT_CAP) |
117 	    V_FW_IQ_CMD_VIID(vi->viid) |
118 	    V_FW_IQ_CMD_IQANUD(X_UPDATEDELIVERY_INTERRUPT));
119 	c.iqdroprss_to_iqesize = htobe16(V_FW_IQ_CMD_IQPCIECH(vi->pi->tx_chan) |
120 	    F_FW_IQ_CMD_IQGTSMODE |
121 	    V_FW_IQ_CMD_IQINTCNTTHRESH(0) |
122 	    V_FW_IQ_CMD_IQESIZE(ilog2(IQ_ESIZE) - 4));
123 	c.iqsize = htobe16(vi->qsize_rxq);
124 	c.iqaddr = htobe64(nm_rxq->iq_ba);
125 	if (cong >= 0) {
126 		c.iqns_to_fl0congen = htobe32(F_FW_IQ_CMD_IQFLINTCONGEN |
127 		    V_FW_IQ_CMD_FL0CNGCHMAP(cong) | F_FW_IQ_CMD_FL0CONGCIF |
128 		    F_FW_IQ_CMD_FL0CONGEN);
129 	}
130 	c.iqns_to_fl0congen |=
131 	    htobe32(V_FW_IQ_CMD_FL0HOSTFCMODE(X_HOSTFCMODE_NONE) |
132 		F_FW_IQ_CMD_FL0FETCHRO | F_FW_IQ_CMD_FL0DATARO |
133 		(fl_pad ? F_FW_IQ_CMD_FL0PADEN : 0) |
134 		(black_hole == 2 ? F_FW_IQ_CMD_FL0PACKEN : 0));
135 	c.fl0dcaen_to_fl0cidxfthresh =
136 	    htobe16(V_FW_IQ_CMD_FL0FBMIN(chip_id(sc) <= CHELSIO_T5 ?
137 		X_FETCHBURSTMIN_128B : X_FETCHBURSTMIN_64B_T6) |
138 		V_FW_IQ_CMD_FL0FBMAX(chip_id(sc) <= CHELSIO_T5 ?
139 		X_FETCHBURSTMAX_512B : X_FETCHBURSTMAX_256B));
140 	c.fl0size = htobe16(na->num_rx_desc / 8 + sp->spg_len / EQ_ESIZE);
141 	c.fl0addr = htobe64(nm_rxq->fl_ba);
142 
143 	rc = -t4_wr_mbox(sc, sc->mbox, &c, sizeof(c), &c);
144 	if (rc != 0) {
145 		device_printf(sc->dev,
146 		    "failed to create netmap ingress queue: %d\n", rc);
147 		return (rc);
148 	}
149 
150 	nm_rxq->iq_cidx = 0;
151 	MPASS(nm_rxq->iq_sidx == vi->qsize_rxq - sp->spg_len / IQ_ESIZE);
152 	nm_rxq->iq_gen = F_RSPD_GEN;
153 	nm_rxq->iq_cntxt_id = be16toh(c.iqid);
154 	nm_rxq->iq_abs_id = be16toh(c.physiqid);
155 	cntxt_id = nm_rxq->iq_cntxt_id - sc->sge.iq_start;
156 	if (cntxt_id >= sc->sge.niq) {
157 		panic ("%s: nm_rxq->iq_cntxt_id (%d) more than the max (%d)",
158 		    __func__, cntxt_id, sc->sge.niq - 1);
159 	}
160 	sc->sge.iqmap[cntxt_id] = (void *)nm_rxq;
161 
162 	nm_rxq->fl_cntxt_id = be16toh(c.fl0id);
163 	nm_rxq->fl_pidx = nm_rxq->fl_cidx = 0;
164 	MPASS(nm_rxq->fl_sidx == na->num_rx_desc);
165 	cntxt_id = nm_rxq->fl_cntxt_id - sc->sge.eq_start;
166 	if (cntxt_id >= sc->sge.neq) {
167 		panic("%s: nm_rxq->fl_cntxt_id (%d) more than the max (%d)",
168 		    __func__, cntxt_id, sc->sge.neq - 1);
169 	}
170 	sc->sge.eqmap[cntxt_id] = (void *)nm_rxq;
171 
172 	nm_rxq->fl_db_val = V_QID(nm_rxq->fl_cntxt_id) |
173 	    sc->chip_params->sge_fl_db;
174 
175 	if (chip_id(sc) >= CHELSIO_T5 && cong >= 0) {
176 		uint32_t param, val;
177 
178 		param = V_FW_PARAMS_MNEM(FW_PARAMS_MNEM_DMAQ) |
179 		    V_FW_PARAMS_PARAM_X(FW_PARAMS_PARAM_DMAQ_CONM_CTXT) |
180 		    V_FW_PARAMS_PARAM_YZ(nm_rxq->iq_cntxt_id);
181 		param = V_FW_PARAMS_MNEM(FW_PARAMS_MNEM_DMAQ) |
182 		    V_FW_PARAMS_PARAM_X(FW_PARAMS_PARAM_DMAQ_CONM_CTXT) |
183 		    V_FW_PARAMS_PARAM_YZ(nm_rxq->iq_cntxt_id);
184 		if (cong == 0)
185 			val = 1 << 19;
186 		else {
187 			val = 2 << 19;
188 			for (i = 0; i < 4; i++) {
189 				if (cong & (1 << i))
190 					val |= 1 << (i << 2);
191 			}
192 		}
193 
194 		rc = -t4_set_params(sc, sc->mbox, sc->pf, 0, 1, &param, &val);
195 		if (rc != 0) {
196 			/* report error but carry on */
197 			device_printf(sc->dev,
198 			    "failed to set congestion manager context for "
199 			    "ingress queue %d: %d\n", nm_rxq->iq_cntxt_id, rc);
200 		}
201 	}
202 
203 	t4_write_reg(sc, sc->sge_gts_reg,
204 	    V_INGRESSQID(nm_rxq->iq_cntxt_id) |
205 	    V_SEINTARM(V_QINTR_TIMER_IDX(holdoff_tmr_idx)));
206 
207 	return (rc);
208 }
209 
210 static int
free_nm_rxq_hwq(struct vi_info * vi,struct sge_nm_rxq * nm_rxq)211 free_nm_rxq_hwq(struct vi_info *vi, struct sge_nm_rxq *nm_rxq)
212 {
213 	struct adapter *sc = vi->pi->adapter;
214 	int rc;
215 
216 	rc = -t4_iq_free(sc, sc->mbox, sc->pf, 0, FW_IQ_TYPE_FL_INT_CAP,
217 	    nm_rxq->iq_cntxt_id, nm_rxq->fl_cntxt_id, 0xffff);
218 	if (rc != 0)
219 		device_printf(sc->dev, "%s: failed for iq %d, fl %d: %d\n",
220 		    __func__, nm_rxq->iq_cntxt_id, nm_rxq->fl_cntxt_id, rc);
221 	return (rc);
222 }
223 
224 static int
alloc_nm_txq_hwq(struct vi_info * vi,struct sge_nm_txq * nm_txq)225 alloc_nm_txq_hwq(struct vi_info *vi, struct sge_nm_txq *nm_txq)
226 {
227 	int rc, cntxt_id;
228 	size_t len;
229 	struct adapter *sc = vi->pi->adapter;
230 	struct netmap_adapter *na = NA(vi->ifp);
231 	struct fw_eq_eth_cmd c;
232 
233 	MPASS(na != NULL);
234 	MPASS(nm_txq->desc != NULL);
235 
236 	len = na->num_tx_desc * EQ_ESIZE + sc->params.sge.spg_len;
237 	bzero(nm_txq->desc, len);
238 
239 	bzero(&c, sizeof(c));
240 	c.op_to_vfn = htobe32(V_FW_CMD_OP(FW_EQ_ETH_CMD) | F_FW_CMD_REQUEST |
241 	    F_FW_CMD_WRITE | F_FW_CMD_EXEC | V_FW_EQ_ETH_CMD_PFN(sc->pf) |
242 	    V_FW_EQ_ETH_CMD_VFN(0));
243 	c.alloc_to_len16 = htobe32(F_FW_EQ_ETH_CMD_ALLOC |
244 	    F_FW_EQ_ETH_CMD_EQSTART | FW_LEN16(c));
245 	c.autoequiqe_to_viid = htobe32(F_FW_EQ_ETH_CMD_AUTOEQUIQE |
246 	    F_FW_EQ_ETH_CMD_AUTOEQUEQE | V_FW_EQ_ETH_CMD_VIID(vi->viid));
247 	c.fetchszm_to_iqid =
248 	    htobe32(V_FW_EQ_ETH_CMD_HOSTFCMODE(X_HOSTFCMODE_NONE) |
249 		V_FW_EQ_ETH_CMD_PCIECHN(vi->pi->tx_chan) | F_FW_EQ_ETH_CMD_FETCHRO |
250 		V_FW_EQ_ETH_CMD_IQID(sc->sge.nm_rxq[nm_txq->iqidx].iq_cntxt_id));
251 	c.dcaen_to_eqsize =
252 	    htobe32(V_FW_EQ_ETH_CMD_FBMIN(chip_id(sc) <= CHELSIO_T5 ?
253 		X_FETCHBURSTMIN_64B : X_FETCHBURSTMIN_64B_T6) |
254 		V_FW_EQ_ETH_CMD_FBMAX(X_FETCHBURSTMAX_512B) |
255 		V_FW_EQ_ETH_CMD_EQSIZE(len / EQ_ESIZE));
256 	c.eqaddr = htobe64(nm_txq->ba);
257 
258 	rc = -t4_wr_mbox(sc, sc->mbox, &c, sizeof(c), &c);
259 	if (rc != 0) {
260 		device_printf(vi->dev,
261 		    "failed to create netmap egress queue: %d\n", rc);
262 		return (rc);
263 	}
264 
265 	nm_txq->cntxt_id = G_FW_EQ_ETH_CMD_EQID(be32toh(c.eqid_pkd));
266 	cntxt_id = nm_txq->cntxt_id - sc->sge.eq_start;
267 	if (cntxt_id >= sc->sge.neq)
268 	    panic("%s: nm_txq->cntxt_id (%d) more than the max (%d)", __func__,
269 		cntxt_id, sc->sge.neq - 1);
270 	sc->sge.eqmap[cntxt_id] = (void *)nm_txq;
271 
272 	nm_txq->pidx = nm_txq->cidx = 0;
273 	MPASS(nm_txq->sidx == na->num_tx_desc);
274 	nm_txq->equiqidx = nm_txq->equeqidx = nm_txq->dbidx = 0;
275 
276 	nm_txq->doorbells = sc->doorbells;
277 	if (isset(&nm_txq->doorbells, DOORBELL_UDB) ||
278 	    isset(&nm_txq->doorbells, DOORBELL_UDBWC) ||
279 	    isset(&nm_txq->doorbells, DOORBELL_WCWR)) {
280 		uint32_t s_qpp = sc->params.sge.eq_s_qpp;
281 		uint32_t mask = (1 << s_qpp) - 1;
282 		volatile uint8_t *udb;
283 
284 		udb = sc->udbs_base + UDBS_DB_OFFSET;
285 		udb += (nm_txq->cntxt_id >> s_qpp) << PAGE_SHIFT;
286 		nm_txq->udb_qid = nm_txq->cntxt_id & mask;
287 		if (nm_txq->udb_qid >= PAGE_SIZE / UDBS_SEG_SIZE)
288 	    		clrbit(&nm_txq->doorbells, DOORBELL_WCWR);
289 		else {
290 			udb += nm_txq->udb_qid << UDBS_SEG_SHIFT;
291 			nm_txq->udb_qid = 0;
292 		}
293 		nm_txq->udb = (volatile void *)udb;
294 	}
295 
296 	return (rc);
297 }
298 
299 static int
free_nm_txq_hwq(struct vi_info * vi,struct sge_nm_txq * nm_txq)300 free_nm_txq_hwq(struct vi_info *vi, struct sge_nm_txq *nm_txq)
301 {
302 	struct adapter *sc = vi->pi->adapter;
303 	int rc;
304 
305 	rc = -t4_eth_eq_free(sc, sc->mbox, sc->pf, 0, nm_txq->cntxt_id);
306 	if (rc != 0)
307 		device_printf(sc->dev, "%s: failed for eq %d: %d\n", __func__,
308 		    nm_txq->cntxt_id, rc);
309 	return (rc);
310 }
311 
312 static int
cxgbe_netmap_on(struct adapter * sc,struct vi_info * vi,struct ifnet * ifp,struct netmap_adapter * na)313 cxgbe_netmap_on(struct adapter *sc, struct vi_info *vi, struct ifnet *ifp,
314     struct netmap_adapter *na)
315 {
316 	struct netmap_slot *slot;
317 	struct sge_nm_rxq *nm_rxq;
318 	struct sge_nm_txq *nm_txq;
319 	int rc, i, j, hwidx;
320 	struct hw_buf_info *hwb;
321 
322 	ASSERT_SYNCHRONIZED_OP(sc);
323 
324 	if ((vi->flags & VI_INIT_DONE) == 0 ||
325 	    (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
326 		return (EAGAIN);
327 
328 	hwb = &sc->sge.hw_buf_info[0];
329 	for (i = 0; i < SGE_FLBUF_SIZES; i++, hwb++) {
330 		if (hwb->size == NETMAP_BUF_SIZE(na))
331 			break;
332 	}
333 	if (i >= SGE_FLBUF_SIZES) {
334 		if_printf(ifp, "no hwidx for netmap buffer size %d.\n",
335 		    NETMAP_BUF_SIZE(na));
336 		return (ENXIO);
337 	}
338 	hwidx = i;
339 
340 	/* Must set caps before calling netmap_reset */
341 	nm_set_native_flags(na);
342 
343 	for_each_nm_rxq(vi, i, nm_rxq) {
344 		alloc_nm_rxq_hwq(vi, nm_rxq, tnl_cong(vi->pi, nm_cong_drop));
345 		nm_rxq->fl_hwidx = hwidx;
346 		slot = netmap_reset(na, NR_RX, i, 0);
347 		MPASS(slot != NULL);	/* XXXNM: error check, not assert */
348 
349 		/* We deal with 8 bufs at a time */
350 		MPASS((na->num_rx_desc & 7) == 0);
351 		MPASS(na->num_rx_desc == nm_rxq->fl_sidx);
352 		for (j = 0; j < nm_rxq->fl_sidx; j++) {
353 			uint64_t ba;
354 
355 			PNMB(na, &slot[j], &ba);
356 			MPASS(ba != 0);
357 			nm_rxq->fl_desc[j] = htobe64(ba | hwidx);
358 		}
359 		j = nm_rxq->fl_pidx = nm_rxq->fl_sidx - 8;
360 		MPASS((j & 7) == 0);
361 		j /= 8;	/* driver pidx to hardware pidx */
362 		wmb();
363 		t4_write_reg(sc, sc->sge_kdoorbell_reg,
364 		    nm_rxq->fl_db_val | V_PIDX(j));
365 
366 		(void) atomic_cmpset_int(&nm_rxq->nm_state, NM_OFF, NM_ON);
367 	}
368 
369 	for_each_nm_txq(vi, i, nm_txq) {
370 		alloc_nm_txq_hwq(vi, nm_txq);
371 		slot = netmap_reset(na, NR_TX, i, 0);
372 		MPASS(slot != NULL);	/* XXXNM: error check, not assert */
373 	}
374 
375 	if (vi->nm_rss == NULL) {
376 		vi->nm_rss = malloc(vi->rss_size * sizeof(uint16_t), M_CXGBE,
377 		    M_ZERO | M_WAITOK);
378 	}
379 	for (i = 0; i < vi->rss_size;) {
380 		for_each_nm_rxq(vi, j, nm_rxq) {
381 			vi->nm_rss[i++] = nm_rxq->iq_abs_id;
382 			if (i == vi->rss_size)
383 				break;
384 		}
385 	}
386 	rc = -t4_config_rss_range(sc, sc->mbox, vi->viid, 0, vi->rss_size,
387 	    vi->nm_rss, vi->rss_size);
388 	if (rc != 0)
389 		if_printf(ifp, "netmap rss_config failed: %d\n", rc);
390 
391 	return (rc);
392 }
393 
394 static int
cxgbe_netmap_off(struct adapter * sc,struct vi_info * vi,struct ifnet * ifp,struct netmap_adapter * na)395 cxgbe_netmap_off(struct adapter *sc, struct vi_info *vi, struct ifnet *ifp,
396     struct netmap_adapter *na)
397 {
398 	int rc, i;
399 	struct sge_nm_txq *nm_txq;
400 	struct sge_nm_rxq *nm_rxq;
401 
402 	ASSERT_SYNCHRONIZED_OP(sc);
403 
404 	if ((vi->flags & VI_INIT_DONE) == 0)
405 		return (0);
406 
407 	rc = -t4_config_rss_range(sc, sc->mbox, vi->viid, 0, vi->rss_size,
408 	    vi->rss, vi->rss_size);
409 	if (rc != 0)
410 		if_printf(ifp, "failed to restore RSS config: %d\n", rc);
411 	nm_clear_native_flags(na);
412 
413 	for_each_nm_txq(vi, i, nm_txq) {
414 		struct sge_qstat *spg = (void *)&nm_txq->desc[nm_txq->sidx];
415 
416 		/* Wait for hw pidx to catch up ... */
417 		while (be16toh(nm_txq->pidx) != spg->pidx)
418 			pause("nmpidx", 1);
419 
420 		/* ... and then for the cidx. */
421 		while (spg->pidx != spg->cidx)
422 			pause("nmcidx", 1);
423 
424 		free_nm_txq_hwq(vi, nm_txq);
425 	}
426 	for_each_nm_rxq(vi, i, nm_rxq) {
427 		while (!atomic_cmpset_int(&nm_rxq->nm_state, NM_ON, NM_OFF))
428 			pause("nmst", 1);
429 
430 		free_nm_rxq_hwq(vi, nm_rxq);
431 	}
432 
433 	return (rc);
434 }
435 
436 static int
cxgbe_netmap_reg(struct netmap_adapter * na,int on)437 cxgbe_netmap_reg(struct netmap_adapter *na, int on)
438 {
439 	struct ifnet *ifp = na->ifp;
440 	struct vi_info *vi = ifp->if_softc;
441 	struct adapter *sc = vi->pi->adapter;
442 	int rc;
443 
444 	rc = begin_synchronized_op(sc, vi, SLEEP_OK | INTR_OK, "t4nmreg");
445 	if (rc != 0)
446 		return (rc);
447 	if (on)
448 		rc = cxgbe_netmap_on(sc, vi, ifp, na);
449 	else
450 		rc = cxgbe_netmap_off(sc, vi, ifp, na);
451 	end_synchronized_op(sc, 0);
452 
453 	return (rc);
454 }
455 
456 /* How many packets can a single type1 WR carry in n descriptors */
457 static inline int
ndesc_to_npkt(const int n)458 ndesc_to_npkt(const int n)
459 {
460 
461 	MPASS(n > 0 && n <= SGE_MAX_WR_NDESC);
462 
463 	return (n * 2 - 1);
464 }
465 #define MAX_NPKT_IN_TYPE1_WR	(ndesc_to_npkt(SGE_MAX_WR_NDESC))
466 
467 /* Space (in descriptors) needed for a type1 WR that carries n packets */
468 static inline int
npkt_to_ndesc(const int n)469 npkt_to_ndesc(const int n)
470 {
471 
472 	MPASS(n > 0 && n <= MAX_NPKT_IN_TYPE1_WR);
473 
474 	return ((n + 2) / 2);
475 }
476 
477 /* Space (in 16B units) needed for a type1 WR that carries n packets */
478 static inline int
npkt_to_len16(const int n)479 npkt_to_len16(const int n)
480 {
481 
482 	MPASS(n > 0 && n <= MAX_NPKT_IN_TYPE1_WR);
483 
484 	return (n * 2 + 1);
485 }
486 
487 #define NMIDXDIFF(q, idx) IDXDIFF((q)->pidx, (q)->idx, (q)->sidx)
488 
489 static void
ring_nm_txq_db(struct adapter * sc,struct sge_nm_txq * nm_txq)490 ring_nm_txq_db(struct adapter *sc, struct sge_nm_txq *nm_txq)
491 {
492 	int n;
493 	u_int db = nm_txq->doorbells;
494 
495 	MPASS(nm_txq->pidx != nm_txq->dbidx);
496 
497 	n = NMIDXDIFF(nm_txq, dbidx);
498 	if (n > 1)
499 		clrbit(&db, DOORBELL_WCWR);
500 	wmb();
501 
502 	switch (ffs(db) - 1) {
503 	case DOORBELL_UDB:
504 		*nm_txq->udb = htole32(V_QID(nm_txq->udb_qid) | V_PIDX(n));
505 		break;
506 
507 	case DOORBELL_WCWR: {
508 		volatile uint64_t *dst, *src;
509 
510 		/*
511 		 * Queues whose 128B doorbell segment fits in the page do not
512 		 * use relative qid (udb_qid is always 0).  Only queues with
513 		 * doorbell segments can do WCWR.
514 		 */
515 		KASSERT(nm_txq->udb_qid == 0 && n == 1,
516 		    ("%s: inappropriate doorbell (0x%x, %d, %d) for nm_txq %p",
517 		    __func__, nm_txq->doorbells, n, nm_txq->pidx, nm_txq));
518 
519 		dst = (volatile void *)((uintptr_t)nm_txq->udb +
520 		    UDBS_WR_OFFSET - UDBS_DB_OFFSET);
521 		src = (void *)&nm_txq->desc[nm_txq->dbidx];
522 		while (src != (void *)&nm_txq->desc[nm_txq->dbidx + 1])
523 			*dst++ = *src++;
524 		wmb();
525 		break;
526 	}
527 
528 	case DOORBELL_UDBWC:
529 		*nm_txq->udb = htole32(V_QID(nm_txq->udb_qid) | V_PIDX(n));
530 		wmb();
531 		break;
532 
533 	case DOORBELL_KDB:
534 		t4_write_reg(sc, sc->sge_kdoorbell_reg,
535 		    V_QID(nm_txq->cntxt_id) | V_PIDX(n));
536 		break;
537 	}
538 	nm_txq->dbidx = nm_txq->pidx;
539 }
540 
541 int lazy_tx_credit_flush = 1;
542 
543 /*
544  * Write work requests to send 'npkt' frames and ring the doorbell to send them
545  * on their way.  No need to check for wraparound.
546  */
547 static void
cxgbe_nm_tx(struct adapter * sc,struct sge_nm_txq * nm_txq,struct netmap_kring * kring,int npkt,int npkt_remaining,int txcsum)548 cxgbe_nm_tx(struct adapter *sc, struct sge_nm_txq *nm_txq,
549     struct netmap_kring *kring, int npkt, int npkt_remaining, int txcsum)
550 {
551 	struct netmap_ring *ring = kring->ring;
552 	struct netmap_slot *slot;
553 	const u_int lim = kring->nkr_num_slots - 1;
554 	struct fw_eth_tx_pkts_wr *wr = (void *)&nm_txq->desc[nm_txq->pidx];
555 	uint16_t len;
556 	uint64_t ba;
557 	struct cpl_tx_pkt_core *cpl;
558 	struct ulptx_sgl *usgl;
559 	int i, n;
560 
561 	while (npkt) {
562 		n = min(npkt, MAX_NPKT_IN_TYPE1_WR);
563 		len = 0;
564 
565 		wr = (void *)&nm_txq->desc[nm_txq->pidx];
566 		wr->op_pkd = htobe32(V_FW_WR_OP(FW_ETH_TX_PKTS_WR));
567 		wr->equiq_to_len16 = htobe32(V_FW_WR_LEN16(npkt_to_len16(n)));
568 		wr->npkt = n;
569 		wr->r3 = 0;
570 		wr->type = 1;
571 		cpl = (void *)(wr + 1);
572 
573 		for (i = 0; i < n; i++) {
574 			slot = &ring->slot[kring->nr_hwcur];
575 			PNMB(kring->na, slot, &ba);
576 			MPASS(ba != 0);
577 
578 			cpl->ctrl0 = nm_txq->cpl_ctrl0;
579 			cpl->pack = 0;
580 			cpl->len = htobe16(slot->len);
581 			/*
582 			 * netmap(4) says "netmap does not use features such as
583 			 * checksum offloading, TCP segmentation offloading,
584 			 * encryption, VLAN encapsulation/decapsulation, etc."
585 			 *
586 			 * So the ncxl interfaces have tx hardware checksumming
587 			 * disabled by default.  But you can override netmap by
588 			 * enabling IFCAP_TXCSUM on the interface manully.
589 			 */
590 			cpl->ctrl1 = txcsum ? 0 :
591 			    htobe64(F_TXPKT_IPCSUM_DIS | F_TXPKT_L4CSUM_DIS);
592 
593 			usgl = (void *)(cpl + 1);
594 			usgl->cmd_nsge = htobe32(V_ULPTX_CMD(ULP_TX_SC_DSGL) |
595 			    V_ULPTX_NSGE(1));
596 			usgl->len0 = htobe32(slot->len);
597 			usgl->addr0 = htobe64(ba);
598 
599 			slot->flags &= ~(NS_REPORT | NS_BUF_CHANGED);
600 			cpl = (void *)(usgl + 1);
601 			MPASS(slot->len + len <= UINT16_MAX);
602 			len += slot->len;
603 			kring->nr_hwcur = nm_next(kring->nr_hwcur, lim);
604 		}
605 		wr->plen = htobe16(len);
606 
607 		npkt -= n;
608 		nm_txq->pidx += npkt_to_ndesc(n);
609 		MPASS(nm_txq->pidx <= nm_txq->sidx);
610 		if (__predict_false(nm_txq->pidx == nm_txq->sidx)) {
611 			/*
612 			 * This routine doesn't know how to write WRs that wrap
613 			 * around.  Make sure it wasn't asked to.
614 			 */
615 			MPASS(npkt == 0);
616 			nm_txq->pidx = 0;
617 		}
618 
619 		if (npkt == 0 && npkt_remaining == 0) {
620 			/* All done. */
621 			if (lazy_tx_credit_flush == 0) {
622 				wr->equiq_to_len16 |= htobe32(F_FW_WR_EQUEQ |
623 				    F_FW_WR_EQUIQ);
624 				nm_txq->equeqidx = nm_txq->pidx;
625 				nm_txq->equiqidx = nm_txq->pidx;
626 			}
627 			ring_nm_txq_db(sc, nm_txq);
628 			return;
629 		}
630 
631 		if (NMIDXDIFF(nm_txq, equiqidx) >= nm_txq->sidx / 2) {
632 			wr->equiq_to_len16 |= htobe32(F_FW_WR_EQUEQ |
633 			    F_FW_WR_EQUIQ);
634 			nm_txq->equeqidx = nm_txq->pidx;
635 			nm_txq->equiqidx = nm_txq->pidx;
636 		} else if (NMIDXDIFF(nm_txq, equeqidx) >= 64) {
637 			wr->equiq_to_len16 |= htobe32(F_FW_WR_EQUEQ);
638 			nm_txq->equeqidx = nm_txq->pidx;
639 		}
640 		if (NMIDXDIFF(nm_txq, dbidx) >= 2 * SGE_MAX_WR_NDESC)
641 			ring_nm_txq_db(sc, nm_txq);
642 	}
643 
644 	/* Will get called again. */
645 	MPASS(npkt_remaining);
646 }
647 
648 /* How many contiguous free descriptors starting at pidx */
649 static inline int
contiguous_ndesc_available(struct sge_nm_txq * nm_txq)650 contiguous_ndesc_available(struct sge_nm_txq *nm_txq)
651 {
652 
653 	if (nm_txq->cidx > nm_txq->pidx)
654 		return (nm_txq->cidx - nm_txq->pidx - 1);
655 	else if (nm_txq->cidx > 0)
656 		return (nm_txq->sidx - nm_txq->pidx);
657 	else
658 		return (nm_txq->sidx - nm_txq->pidx - 1);
659 }
660 
661 static int
reclaim_nm_tx_desc(struct sge_nm_txq * nm_txq)662 reclaim_nm_tx_desc(struct sge_nm_txq *nm_txq)
663 {
664 	struct sge_qstat *spg = (void *)&nm_txq->desc[nm_txq->sidx];
665 	uint16_t hw_cidx = spg->cidx;	/* snapshot */
666 	struct fw_eth_tx_pkts_wr *wr;
667 	int n = 0;
668 
669 	hw_cidx = be16toh(hw_cidx);
670 
671 	while (nm_txq->cidx != hw_cidx) {
672 		wr = (void *)&nm_txq->desc[nm_txq->cidx];
673 
674 		MPASS(wr->op_pkd == htobe32(V_FW_WR_OP(FW_ETH_TX_PKTS_WR)));
675 		MPASS(wr->type == 1);
676 		MPASS(wr->npkt > 0 && wr->npkt <= MAX_NPKT_IN_TYPE1_WR);
677 
678 		n += wr->npkt;
679 		nm_txq->cidx += npkt_to_ndesc(wr->npkt);
680 
681 		/*
682 		 * We never sent a WR that wrapped around so the credits coming
683 		 * back, WR by WR, should never cause the cidx to wrap around
684 		 * either.
685 		 */
686 		MPASS(nm_txq->cidx <= nm_txq->sidx);
687 		if (__predict_false(nm_txq->cidx == nm_txq->sidx))
688 			nm_txq->cidx = 0;
689 	}
690 
691 	return (n);
692 }
693 
694 static int
cxgbe_netmap_txsync(struct netmap_kring * kring,int flags)695 cxgbe_netmap_txsync(struct netmap_kring *kring, int flags)
696 {
697 	struct netmap_adapter *na = kring->na;
698 	struct ifnet *ifp = na->ifp;
699 	struct vi_info *vi = ifp->if_softc;
700 	struct adapter *sc = vi->pi->adapter;
701 	struct sge_nm_txq *nm_txq = &sc->sge.nm_txq[vi->first_nm_txq + kring->ring_id];
702 	const u_int head = kring->rhead;
703 	u_int reclaimed = 0;
704 	int n, d, npkt_remaining, ndesc_remaining, txcsum;
705 
706 	/*
707 	 * Tx was at kring->nr_hwcur last time around and now we need to advance
708 	 * to kring->rhead.  Note that the driver's pidx moves independent of
709 	 * netmap's kring->nr_hwcur (pidx counts descriptors and the relation
710 	 * between descriptors and frames isn't 1:1).
711 	 */
712 
713 	npkt_remaining = head >= kring->nr_hwcur ? head - kring->nr_hwcur :
714 	    kring->nkr_num_slots - kring->nr_hwcur + head;
715 	txcsum = ifp->if_capenable & (IFCAP_TXCSUM | IFCAP_TXCSUM_IPV6);
716 	while (npkt_remaining) {
717 		reclaimed += reclaim_nm_tx_desc(nm_txq);
718 		ndesc_remaining = contiguous_ndesc_available(nm_txq);
719 		/* Can't run out of descriptors with packets still remaining */
720 		MPASS(ndesc_remaining > 0);
721 
722 		/* # of desc needed to tx all remaining packets */
723 		d = (npkt_remaining / MAX_NPKT_IN_TYPE1_WR) * SGE_MAX_WR_NDESC;
724 		if (npkt_remaining % MAX_NPKT_IN_TYPE1_WR)
725 			d += npkt_to_ndesc(npkt_remaining % MAX_NPKT_IN_TYPE1_WR);
726 
727 		if (d <= ndesc_remaining)
728 			n = npkt_remaining;
729 		else {
730 			/* Can't send all, calculate how many can be sent */
731 			n = (ndesc_remaining / SGE_MAX_WR_NDESC) *
732 			    MAX_NPKT_IN_TYPE1_WR;
733 			if (ndesc_remaining % SGE_MAX_WR_NDESC)
734 				n += ndesc_to_npkt(ndesc_remaining % SGE_MAX_WR_NDESC);
735 		}
736 
737 		/* Send n packets and update nm_txq->pidx and kring->nr_hwcur */
738 		npkt_remaining -= n;
739 		cxgbe_nm_tx(sc, nm_txq, kring, n, npkt_remaining, txcsum);
740 	}
741 	MPASS(npkt_remaining == 0);
742 	MPASS(kring->nr_hwcur == head);
743 	MPASS(nm_txq->dbidx == nm_txq->pidx);
744 
745 	/*
746 	 * Second part: reclaim buffers for completed transmissions.
747 	 */
748 	if (reclaimed || flags & NAF_FORCE_RECLAIM || nm_kr_txempty(kring)) {
749 		reclaimed += reclaim_nm_tx_desc(nm_txq);
750 		kring->nr_hwtail += reclaimed;
751 		if (kring->nr_hwtail >= kring->nkr_num_slots)
752 			kring->nr_hwtail -= kring->nkr_num_slots;
753 	}
754 
755 	return (0);
756 }
757 
758 static int
cxgbe_netmap_rxsync(struct netmap_kring * kring,int flags)759 cxgbe_netmap_rxsync(struct netmap_kring *kring, int flags)
760 {
761 	struct netmap_adapter *na = kring->na;
762 	struct netmap_ring *ring = kring->ring;
763 	struct ifnet *ifp = na->ifp;
764 	struct vi_info *vi = ifp->if_softc;
765 	struct adapter *sc = vi->pi->adapter;
766 	struct sge_nm_rxq *nm_rxq = &sc->sge.nm_rxq[vi->first_nm_rxq + kring->ring_id];
767 	u_int const head = kring->rhead;
768 	u_int n;
769 	int force_update = (flags & NAF_FORCE_READ) || kring->nr_kflags & NKR_PENDINTR;
770 
771 	if (black_hole)
772 		return (0);	/* No updates ever. */
773 
774 	if (netmap_no_pendintr || force_update) {
775 		kring->nr_hwtail = atomic_load_acq_32(&nm_rxq->fl_cidx);
776 		kring->nr_kflags &= ~NKR_PENDINTR;
777 	}
778 
779 	/* Userspace done with buffers from kring->nr_hwcur to head */
780 	n = head >= kring->nr_hwcur ? head - kring->nr_hwcur :
781 	    kring->nkr_num_slots - kring->nr_hwcur + head;
782 	n &= ~7U;
783 	if (n > 0) {
784 		u_int fl_pidx = nm_rxq->fl_pidx;
785 		struct netmap_slot *slot = &ring->slot[fl_pidx];
786 		uint64_t ba;
787 		int i, dbinc = 0, hwidx = nm_rxq->fl_hwidx;
788 
789 		/*
790 		 * We always deal with 8 buffers at a time.  We must have
791 		 * stopped at an 8B boundary (fl_pidx) last time around and we
792 		 * must have a multiple of 8B buffers to give to the freelist.
793 		 */
794 		MPASS((fl_pidx & 7) == 0);
795 		MPASS((n & 7) == 0);
796 
797 		IDXINCR(kring->nr_hwcur, n, kring->nkr_num_slots);
798 		IDXINCR(nm_rxq->fl_pidx, n, nm_rxq->fl_sidx);
799 
800 		while (n > 0) {
801 			for (i = 0; i < 8; i++, fl_pidx++, slot++) {
802 				PNMB(na, slot, &ba);
803 				MPASS(ba != 0);
804 				nm_rxq->fl_desc[fl_pidx] = htobe64(ba | hwidx);
805 				slot->flags &= ~NS_BUF_CHANGED;
806 				MPASS(fl_pidx <= nm_rxq->fl_sidx);
807 			}
808 			n -= 8;
809 			if (fl_pidx == nm_rxq->fl_sidx) {
810 				fl_pidx = 0;
811 				slot = &ring->slot[0];
812 			}
813 			if (++dbinc == 8 && n >= 32) {
814 				wmb();
815 				t4_write_reg(sc, sc->sge_kdoorbell_reg,
816 				    nm_rxq->fl_db_val | V_PIDX(dbinc));
817 				dbinc = 0;
818 			}
819 		}
820 		MPASS(nm_rxq->fl_pidx == fl_pidx);
821 
822 		if (dbinc > 0) {
823 			wmb();
824 			t4_write_reg(sc, sc->sge_kdoorbell_reg,
825 			    nm_rxq->fl_db_val | V_PIDX(dbinc));
826 		}
827 	}
828 
829 	return (0);
830 }
831 
832 void
cxgbe_nm_attach(struct vi_info * vi)833 cxgbe_nm_attach(struct vi_info *vi)
834 {
835 	struct port_info *pi;
836 	struct adapter *sc;
837 	struct netmap_adapter na;
838 
839 	MPASS(vi->nnmrxq > 0);
840 	MPASS(vi->ifp != NULL);
841 
842 	pi = vi->pi;
843 	sc = pi->adapter;
844 
845 	bzero(&na, sizeof(na));
846 
847 	na.ifp = vi->ifp;
848 	na.na_flags = NAF_BDG_MAYSLEEP;
849 
850 	/* Netmap doesn't know about the space reserved for the status page. */
851 	na.num_tx_desc = vi->qsize_txq - sc->params.sge.spg_len / EQ_ESIZE;
852 
853 	/*
854 	 * The freelist's cidx/pidx drives netmap's rx cidx/pidx.  So
855 	 * num_rx_desc is based on the number of buffers that can be held in the
856 	 * freelist, and not the number of entries in the iq.  (These two are
857 	 * not exactly the same due to the space taken up by the status page).
858 	 */
859 	na.num_rx_desc = rounddown(vi->qsize_rxq, 8);
860 	na.nm_txsync = cxgbe_netmap_txsync;
861 	na.nm_rxsync = cxgbe_netmap_rxsync;
862 	na.nm_register = cxgbe_netmap_reg;
863 	na.num_tx_rings = vi->nnmtxq;
864 	na.num_rx_rings = vi->nnmrxq;
865 	netmap_attach(&na);	/* This adds IFCAP_NETMAP to if_capabilities */
866 }
867 
868 void
cxgbe_nm_detach(struct vi_info * vi)869 cxgbe_nm_detach(struct vi_info *vi)
870 {
871 
872 	MPASS(vi->nnmrxq > 0);
873 	MPASS(vi->ifp != NULL);
874 
875 	netmap_detach(vi->ifp);
876 }
877 
878 static inline const void *
unwrap_nm_fw6_msg(const struct cpl_fw6_msg * cpl)879 unwrap_nm_fw6_msg(const struct cpl_fw6_msg *cpl)
880 {
881 
882 	MPASS(cpl->type == FW_TYPE_RSSCPL || cpl->type == FW6_TYPE_RSSCPL);
883 
884 	/* data[0] is RSS header */
885 	return (&cpl->data[1]);
886 }
887 
888 static void
handle_nm_sge_egr_update(struct adapter * sc,struct ifnet * ifp,const struct cpl_sge_egr_update * egr)889 handle_nm_sge_egr_update(struct adapter *sc, struct ifnet *ifp,
890     const struct cpl_sge_egr_update *egr)
891 {
892 	uint32_t oq;
893 	struct sge_nm_txq *nm_txq;
894 
895 	oq = be32toh(egr->opcode_qid);
896 	MPASS(G_CPL_OPCODE(oq) == CPL_SGE_EGR_UPDATE);
897 	nm_txq = (void *)sc->sge.eqmap[G_EGR_QID(oq) - sc->sge.eq_start];
898 
899 	netmap_tx_irq(ifp, nm_txq->nid);
900 }
901 
902 void
service_nm_rxq(struct sge_nm_rxq * nm_rxq)903 service_nm_rxq(struct sge_nm_rxq *nm_rxq)
904 {
905 	struct vi_info *vi = nm_rxq->vi;
906 	struct adapter *sc = vi->pi->adapter;
907 	struct ifnet *ifp = vi->ifp;
908 	struct netmap_adapter *na = NA(ifp);
909 	struct netmap_kring *kring = na->rx_rings[nm_rxq->nid];
910 	struct netmap_ring *ring = kring->ring;
911 	struct iq_desc *d = &nm_rxq->iq_desc[nm_rxq->iq_cidx];
912 	const void *cpl;
913 	uint32_t lq;
914 	u_int n = 0, work = 0;
915 	uint8_t opcode;
916 	uint32_t fl_cidx = atomic_load_acq_32(&nm_rxq->fl_cidx);
917 	u_int fl_credits = fl_cidx & 7;
918 
919 	while ((d->rsp.u.type_gen & F_RSPD_GEN) == nm_rxq->iq_gen) {
920 
921 		rmb();
922 
923 		lq = be32toh(d->rsp.pldbuflen_qid);
924 		opcode = d->rss.opcode;
925 		cpl = &d->cpl[0];
926 
927 		switch (G_RSPD_TYPE(d->rsp.u.type_gen)) {
928 		case X_RSPD_TYPE_FLBUF:
929 			if (black_hole != 2) {
930 				/* No buffer packing so new buf every time */
931 				MPASS(lq & F_RSPD_NEWBUF);
932 			}
933 
934 			/* fall through */
935 
936 		case X_RSPD_TYPE_CPL:
937 			MPASS(opcode < NUM_CPL_CMDS);
938 
939 			switch (opcode) {
940 			case CPL_FW4_MSG:
941 			case CPL_FW6_MSG:
942 				cpl = unwrap_nm_fw6_msg(cpl);
943 				/* fall through */
944 			case CPL_SGE_EGR_UPDATE:
945 				handle_nm_sge_egr_update(sc, ifp, cpl);
946 				break;
947 			case CPL_RX_PKT:
948 				ring->slot[fl_cidx].len = G_RSPD_LEN(lq) -
949 				    sc->params.sge.fl_pktshift;
950 				ring->slot[fl_cidx].flags = 0;
951 				fl_cidx += (lq & F_RSPD_NEWBUF) ? 1 : 0;
952 				fl_credits += (lq & F_RSPD_NEWBUF) ? 1 : 0;
953 				if (__predict_false(fl_cidx == nm_rxq->fl_sidx))
954 					fl_cidx = 0;
955 				break;
956 			default:
957 				panic("%s: unexpected opcode 0x%x on nm_rxq %p",
958 				    __func__, opcode, nm_rxq);
959 			}
960 			break;
961 
962 		case X_RSPD_TYPE_INTR:
963 			/* Not equipped to handle forwarded interrupts. */
964 			panic("%s: netmap queue received interrupt for iq %u\n",
965 			    __func__, lq);
966 
967 		default:
968 			panic("%s: illegal response type %d on nm_rxq %p",
969 			    __func__, G_RSPD_TYPE(d->rsp.u.type_gen), nm_rxq);
970 		}
971 
972 		d++;
973 		if (__predict_false(++nm_rxq->iq_cidx == nm_rxq->iq_sidx)) {
974 			nm_rxq->iq_cidx = 0;
975 			d = &nm_rxq->iq_desc[0];
976 			nm_rxq->iq_gen ^= F_RSPD_GEN;
977 		}
978 
979 		if (__predict_false(++n == rx_ndesc)) {
980 			atomic_store_rel_32(&nm_rxq->fl_cidx, fl_cidx);
981 			if (black_hole && fl_credits >= 8) {
982 				fl_credits /= 8;
983 				IDXINCR(nm_rxq->fl_pidx, fl_credits * 8,
984 				    nm_rxq->fl_sidx);
985 				t4_write_reg(sc, sc->sge_kdoorbell_reg,
986 				    nm_rxq->fl_db_val | V_PIDX(fl_credits));
987 				fl_credits = fl_cidx & 7;
988 			} else if (!black_hole) {
989 				netmap_rx_irq(ifp, nm_rxq->nid, &work);
990 				MPASS(work != 0);
991 			}
992 			t4_write_reg(sc, sc->sge_gts_reg,
993 			    V_CIDXINC(n) | V_INGRESSQID(nm_rxq->iq_cntxt_id) |
994 			    V_SEINTARM(V_QINTR_TIMER_IDX(X_TIMERREG_UPDATE_CIDX)));
995 			n = 0;
996 		}
997 	}
998 
999 	atomic_store_rel_32(&nm_rxq->fl_cidx, fl_cidx);
1000 	if (black_hole) {
1001 		fl_credits /= 8;
1002 		IDXINCR(nm_rxq->fl_pidx, fl_credits * 8, nm_rxq->fl_sidx);
1003 		t4_write_reg(sc, sc->sge_kdoorbell_reg,
1004 		    nm_rxq->fl_db_val | V_PIDX(fl_credits));
1005 	} else
1006 		netmap_rx_irq(ifp, nm_rxq->nid, &work);
1007 
1008 	t4_write_reg(sc, sc->sge_gts_reg, V_CIDXINC(n) |
1009 	    V_INGRESSQID((u32)nm_rxq->iq_cntxt_id) |
1010 	    V_SEINTARM(V_QINTR_TIMER_IDX(holdoff_tmr_idx)));
1011 }
1012 #endif
1013