xref: /freebsd/sys/dev/cxgb/cxgb_sge.c (revision 18054d0220cfc8df9c9568c437bd6fbb59d53c3c)
1 /**************************************************************************
2 SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 
4 Copyright (c) 2007-2009, Chelsio Inc.
5 All rights reserved.
6 
7 Redistribution and use in source and binary forms, with or without
8 modification, are permitted provided that the following conditions are met:
9 
10  1. Redistributions of source code must retain the above copyright notice,
11     this list of conditions and the following disclaimer.
12 
13  2. Neither the name of the Chelsio Corporation nor the names of its
14     contributors may be used to endorse or promote products derived from
15     this software without specific prior written permission.
16 
17 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
18 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
21 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
24 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
26 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27 POSSIBILITY OF SUCH DAMAGE.
28 
29 ***************************************************************************/
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include "opt_inet6.h"
35 #include "opt_inet.h"
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/kernel.h>
40 #include <sys/module.h>
41 #include <sys/bus.h>
42 #include <sys/conf.h>
43 #include <machine/bus.h>
44 #include <machine/resource.h>
45 #include <sys/rman.h>
46 #include <sys/queue.h>
47 #include <sys/sysctl.h>
48 #include <sys/taskqueue.h>
49 
50 #include <sys/proc.h>
51 #include <sys/sbuf.h>
52 #include <sys/sched.h>
53 #include <sys/smp.h>
54 #include <sys/systm.h>
55 #include <sys/syslog.h>
56 #include <sys/socket.h>
57 #include <sys/sglist.h>
58 
59 #include <net/if.h>
60 #include <net/if_var.h>
61 #include <net/bpf.h>
62 #include <net/ethernet.h>
63 #include <net/if_vlan_var.h>
64 
65 #include <netinet/in_systm.h>
66 #include <netinet/in.h>
67 #include <netinet/ip.h>
68 #include <netinet/ip6.h>
69 #include <netinet/tcp.h>
70 
71 #include <dev/pci/pcireg.h>
72 #include <dev/pci/pcivar.h>
73 
74 #include <vm/vm.h>
75 #include <vm/pmap.h>
76 
77 #include <cxgb_include.h>
78 #include <sys/mvec.h>
79 
80 int	txq_fills = 0;
81 int	multiq_tx_enable = 1;
82 
83 #ifdef TCP_OFFLOAD
84 CTASSERT(NUM_CPL_HANDLERS >= NUM_CPL_CMDS);
85 #endif
86 
87 extern struct sysctl_oid_list sysctl__hw_cxgb_children;
88 int cxgb_txq_buf_ring_size = TX_ETH_Q_SIZE;
89 SYSCTL_INT(_hw_cxgb, OID_AUTO, txq_mr_size, CTLFLAG_RDTUN, &cxgb_txq_buf_ring_size, 0,
90     "size of per-queue mbuf ring");
91 
92 static int cxgb_tx_coalesce_force = 0;
93 SYSCTL_INT(_hw_cxgb, OID_AUTO, tx_coalesce_force, CTLFLAG_RWTUN,
94     &cxgb_tx_coalesce_force, 0,
95     "coalesce small packets into a single work request regardless of ring state");
96 
97 #define	COALESCE_START_DEFAULT		TX_ETH_Q_SIZE>>1
98 #define	COALESCE_START_MAX		(TX_ETH_Q_SIZE-(TX_ETH_Q_SIZE>>3))
99 #define	COALESCE_STOP_DEFAULT		TX_ETH_Q_SIZE>>2
100 #define	COALESCE_STOP_MIN		TX_ETH_Q_SIZE>>5
101 #define	TX_RECLAIM_DEFAULT		TX_ETH_Q_SIZE>>5
102 #define	TX_RECLAIM_MAX			TX_ETH_Q_SIZE>>2
103 #define	TX_RECLAIM_MIN			TX_ETH_Q_SIZE>>6
104 
105 
106 static int cxgb_tx_coalesce_enable_start = COALESCE_START_DEFAULT;
107 SYSCTL_INT(_hw_cxgb, OID_AUTO, tx_coalesce_enable_start, CTLFLAG_RWTUN,
108     &cxgb_tx_coalesce_enable_start, 0,
109     "coalesce enable threshold");
110 static int cxgb_tx_coalesce_enable_stop = COALESCE_STOP_DEFAULT;
111 SYSCTL_INT(_hw_cxgb, OID_AUTO, tx_coalesce_enable_stop, CTLFLAG_RWTUN,
112     &cxgb_tx_coalesce_enable_stop, 0,
113     "coalesce disable threshold");
114 static int cxgb_tx_reclaim_threshold = TX_RECLAIM_DEFAULT;
115 SYSCTL_INT(_hw_cxgb, OID_AUTO, tx_reclaim_threshold, CTLFLAG_RWTUN,
116     &cxgb_tx_reclaim_threshold, 0,
117     "tx cleaning minimum threshold");
118 
119 /*
120  * XXX don't re-enable this until TOE stops assuming
121  * we have an m_ext
122  */
123 static int recycle_enable = 0;
124 
125 extern int cxgb_use_16k_clusters;
126 extern int nmbjumbop;
127 extern int nmbjumbo9;
128 extern int nmbjumbo16;
129 
130 #define USE_GTS 0
131 
132 #define SGE_RX_SM_BUF_SIZE	1536
133 #define SGE_RX_DROP_THRES	16
134 #define SGE_RX_COPY_THRES	128
135 
136 /*
137  * Period of the Tx buffer reclaim timer.  This timer does not need to run
138  * frequently as Tx buffers are usually reclaimed by new Tx packets.
139  */
140 #define TX_RECLAIM_PERIOD       (hz >> 1)
141 
142 /*
143  * Values for sge_txq.flags
144  */
145 enum {
146 	TXQ_RUNNING	= 1 << 0,  /* fetch engine is running */
147 	TXQ_LAST_PKT_DB = 1 << 1,  /* last packet rang the doorbell */
148 };
149 
150 struct tx_desc {
151 	uint64_t	flit[TX_DESC_FLITS];
152 } __packed;
153 
154 struct rx_desc {
155 	uint32_t	addr_lo;
156 	uint32_t	len_gen;
157 	uint32_t	gen2;
158 	uint32_t	addr_hi;
159 } __packed;
160 
161 struct rsp_desc {               /* response queue descriptor */
162 	struct rss_header	rss_hdr;
163 	uint32_t		flags;
164 	uint32_t		len_cq;
165 	uint8_t			imm_data[47];
166 	uint8_t			intr_gen;
167 } __packed;
168 
169 #define RX_SW_DESC_MAP_CREATED	(1 << 0)
170 #define TX_SW_DESC_MAP_CREATED	(1 << 1)
171 #define RX_SW_DESC_INUSE        (1 << 3)
172 #define TX_SW_DESC_MAPPED       (1 << 4)
173 
174 #define RSPQ_NSOP_NEOP           G_RSPD_SOP_EOP(0)
175 #define RSPQ_EOP                 G_RSPD_SOP_EOP(F_RSPD_EOP)
176 #define RSPQ_SOP                 G_RSPD_SOP_EOP(F_RSPD_SOP)
177 #define RSPQ_SOP_EOP             G_RSPD_SOP_EOP(F_RSPD_SOP|F_RSPD_EOP)
178 
179 struct tx_sw_desc {                /* SW state per Tx descriptor */
180 	struct mbuf	*m;
181 	bus_dmamap_t	map;
182 	int		flags;
183 };
184 
185 struct rx_sw_desc {                /* SW state per Rx descriptor */
186 	caddr_t		rxsd_cl;
187 	struct mbuf	*m;
188 	bus_dmamap_t	map;
189 	int		flags;
190 };
191 
192 struct txq_state {
193 	unsigned int	compl;
194 	unsigned int	gen;
195 	unsigned int	pidx;
196 };
197 
198 struct refill_fl_cb_arg {
199 	int               error;
200 	bus_dma_segment_t seg;
201 	int               nseg;
202 };
203 
204 
205 /*
206  * Maps a number of flits to the number of Tx descriptors that can hold them.
207  * The formula is
208  *
209  * desc = 1 + (flits - 2) / (WR_FLITS - 1).
210  *
211  * HW allows up to 4 descriptors to be combined into a WR.
212  */
213 static uint8_t flit_desc_map[] = {
214 	0,
215 #if SGE_NUM_GENBITS == 1
216 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
217 	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
218 	3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
219 	4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4
220 #elif SGE_NUM_GENBITS == 2
221 	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
222 	2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
223 	3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
224 	4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4,
225 #else
226 # error "SGE_NUM_GENBITS must be 1 or 2"
227 #endif
228 };
229 
230 #define	TXQ_LOCK_ASSERT(qs)	mtx_assert(&(qs)->lock, MA_OWNED)
231 #define	TXQ_TRYLOCK(qs)		mtx_trylock(&(qs)->lock)
232 #define	TXQ_LOCK(qs)		mtx_lock(&(qs)->lock)
233 #define	TXQ_UNLOCK(qs)		mtx_unlock(&(qs)->lock)
234 #define	TXQ_RING_EMPTY(qs)	drbr_empty((qs)->port->ifp, (qs)->txq[TXQ_ETH].txq_mr)
235 #define	TXQ_RING_NEEDS_ENQUEUE(qs)					\
236 	drbr_needs_enqueue((qs)->port->ifp, (qs)->txq[TXQ_ETH].txq_mr)
237 #define	TXQ_RING_FLUSH(qs)	drbr_flush((qs)->port->ifp, (qs)->txq[TXQ_ETH].txq_mr)
238 #define	TXQ_RING_DEQUEUE_COND(qs, func, arg)				\
239 	drbr_dequeue_cond((qs)->port->ifp, (qs)->txq[TXQ_ETH].txq_mr, func, arg)
240 #define	TXQ_RING_DEQUEUE(qs) \
241 	drbr_dequeue((qs)->port->ifp, (qs)->txq[TXQ_ETH].txq_mr)
242 
243 int cxgb_debug = 0;
244 
245 static void sge_timer_cb(void *arg);
246 static void sge_timer_reclaim(void *arg, int ncount);
247 static void sge_txq_reclaim_handler(void *arg, int ncount);
248 static void cxgb_start_locked(struct sge_qset *qs);
249 
250 /*
251  * XXX need to cope with bursty scheduling by looking at a wider
252  * window than we are now for determining the need for coalescing
253  *
254  */
255 static __inline uint64_t
256 check_pkt_coalesce(struct sge_qset *qs)
257 {
258         struct adapter *sc;
259         struct sge_txq *txq;
260 	uint8_t *fill;
261 
262 	if (__predict_false(cxgb_tx_coalesce_force))
263 		return (1);
264 	txq = &qs->txq[TXQ_ETH];
265         sc = qs->port->adapter;
266 	fill = &sc->tunq_fill[qs->idx];
267 
268 	if (cxgb_tx_coalesce_enable_start > COALESCE_START_MAX)
269 		cxgb_tx_coalesce_enable_start = COALESCE_START_MAX;
270 	if (cxgb_tx_coalesce_enable_stop < COALESCE_STOP_MIN)
271 		cxgb_tx_coalesce_enable_start = COALESCE_STOP_MIN;
272 	/*
273 	 * if the hardware transmit queue is more than 1/8 full
274 	 * we mark it as coalescing - we drop back from coalescing
275 	 * when we go below 1/32 full and there are no packets enqueued,
276 	 * this provides us with some degree of hysteresis
277 	 */
278         if (*fill != 0 && (txq->in_use <= cxgb_tx_coalesce_enable_stop) &&
279 	    TXQ_RING_EMPTY(qs) && (qs->coalescing == 0))
280                 *fill = 0;
281         else if (*fill == 0 && (txq->in_use >= cxgb_tx_coalesce_enable_start))
282                 *fill = 1;
283 
284 	return (sc->tunq_coalesce);
285 }
286 
287 #ifdef __LP64__
288 static void
289 set_wr_hdr(struct work_request_hdr *wrp, uint32_t wr_hi, uint32_t wr_lo)
290 {
291 	uint64_t wr_hilo;
292 #if _BYTE_ORDER == _LITTLE_ENDIAN
293 	wr_hilo = wr_hi;
294 	wr_hilo |= (((uint64_t)wr_lo)<<32);
295 #else
296 	wr_hilo = wr_lo;
297 	wr_hilo |= (((uint64_t)wr_hi)<<32);
298 #endif
299 	wrp->wrh_hilo = wr_hilo;
300 }
301 #else
302 static void
303 set_wr_hdr(struct work_request_hdr *wrp, uint32_t wr_hi, uint32_t wr_lo)
304 {
305 
306 	wrp->wrh_hi = wr_hi;
307 	wmb();
308 	wrp->wrh_lo = wr_lo;
309 }
310 #endif
311 
312 struct coalesce_info {
313 	int count;
314 	int nbytes;
315 	int noncoal;
316 };
317 
318 static int
319 coalesce_check(struct mbuf *m, void *arg)
320 {
321 	struct coalesce_info *ci = arg;
322 
323 	if ((m->m_next != NULL) ||
324 	    ((mtod(m, vm_offset_t) & PAGE_MASK) + m->m_len > PAGE_SIZE))
325 		ci->noncoal = 1;
326 
327 	if ((ci->count == 0) || (ci->noncoal == 0 && (ci->count < 7) &&
328 	    (ci->nbytes + m->m_len <= 10500))) {
329 		ci->count++;
330 		ci->nbytes += m->m_len;
331 		return (1);
332 	}
333 	return (0);
334 }
335 
336 static struct mbuf *
337 cxgb_dequeue(struct sge_qset *qs)
338 {
339 	struct mbuf *m, *m_head, *m_tail;
340 	struct coalesce_info ci;
341 
342 
343 	if (check_pkt_coalesce(qs) == 0)
344 		return TXQ_RING_DEQUEUE(qs);
345 
346 	m_head = m_tail = NULL;
347 	ci.count = ci.nbytes = ci.noncoal = 0;
348 	do {
349 		m = TXQ_RING_DEQUEUE_COND(qs, coalesce_check, &ci);
350 		if (m_head == NULL) {
351 			m_tail = m_head = m;
352 		} else if (m != NULL) {
353 			m_tail->m_nextpkt = m;
354 			m_tail = m;
355 		}
356 	} while (m != NULL);
357 	if (ci.count > 7)
358 		panic("trying to coalesce %d packets in to one WR", ci.count);
359 	return (m_head);
360 }
361 
362 /**
363  *	reclaim_completed_tx - reclaims completed Tx descriptors
364  *	@adapter: the adapter
365  *	@q: the Tx queue to reclaim completed descriptors from
366  *
367  *	Reclaims Tx descriptors that the SGE has indicated it has processed,
368  *	and frees the associated buffers if possible.  Called with the Tx
369  *	queue's lock held.
370  */
371 static __inline int
372 reclaim_completed_tx(struct sge_qset *qs, int reclaim_min, int queue)
373 {
374 	struct sge_txq *q = &qs->txq[queue];
375 	int reclaim = desc_reclaimable(q);
376 
377 	if ((cxgb_tx_reclaim_threshold > TX_RECLAIM_MAX) ||
378 	    (cxgb_tx_reclaim_threshold < TX_RECLAIM_MIN))
379 		cxgb_tx_reclaim_threshold = TX_RECLAIM_DEFAULT;
380 
381 	if (reclaim < reclaim_min)
382 		return (0);
383 
384 	mtx_assert(&qs->lock, MA_OWNED);
385 	if (reclaim > 0) {
386 		t3_free_tx_desc(qs, reclaim, queue);
387 		q->cleaned += reclaim;
388 		q->in_use -= reclaim;
389 	}
390 	if (isset(&qs->txq_stopped, TXQ_ETH))
391                 clrbit(&qs->txq_stopped, TXQ_ETH);
392 
393 	return (reclaim);
394 }
395 
396 #ifdef DEBUGNET
397 int
398 cxgb_debugnet_poll_tx(struct sge_qset *qs)
399 {
400 
401 	return (reclaim_completed_tx(qs, TX_RECLAIM_MAX, TXQ_ETH));
402 }
403 #endif
404 
405 /**
406  *	should_restart_tx - are there enough resources to restart a Tx queue?
407  *	@q: the Tx queue
408  *
409  *	Checks if there are enough descriptors to restart a suspended Tx queue.
410  */
411 static __inline int
412 should_restart_tx(const struct sge_txq *q)
413 {
414 	unsigned int r = q->processed - q->cleaned;
415 
416 	return q->in_use - r < (q->size >> 1);
417 }
418 
419 /**
420  *	t3_sge_init - initialize SGE
421  *	@adap: the adapter
422  *	@p: the SGE parameters
423  *
424  *	Performs SGE initialization needed every time after a chip reset.
425  *	We do not initialize any of the queue sets here, instead the driver
426  *	top-level must request those individually.  We also do not enable DMA
427  *	here, that should be done after the queues have been set up.
428  */
429 void
430 t3_sge_init(adapter_t *adap, struct sge_params *p)
431 {
432 	u_int ctrl, ups;
433 
434 	ups = 0; /* = ffs(pci_resource_len(adap->pdev, 2) >> 12); */
435 
436 	ctrl = F_DROPPKT | V_PKTSHIFT(2) | F_FLMODE | F_AVOIDCQOVFL |
437 	       F_CQCRDTCTRL | F_CONGMODE | F_TNLFLMODE | F_FATLPERREN |
438 	       V_HOSTPAGESIZE(PAGE_SHIFT - 11) | F_BIGENDIANINGRESS |
439 	       V_USERSPACESIZE(ups ? ups - 1 : 0) | F_ISCSICOALESCING;
440 #if SGE_NUM_GENBITS == 1
441 	ctrl |= F_EGRGENCTRL;
442 #endif
443 	if (adap->params.rev > 0) {
444 		if (!(adap->flags & (USING_MSIX | USING_MSI)))
445 			ctrl |= F_ONEINTMULTQ | F_OPTONEINTMULTQ;
446 	}
447 	t3_write_reg(adap, A_SG_CONTROL, ctrl);
448 	t3_write_reg(adap, A_SG_EGR_RCQ_DRB_THRSH, V_HIRCQDRBTHRSH(512) |
449 		     V_LORCQDRBTHRSH(512));
450 	t3_write_reg(adap, A_SG_TIMER_TICK, core_ticks_per_usec(adap) / 10);
451 	t3_write_reg(adap, A_SG_CMDQ_CREDIT_TH, V_THRESHOLD(32) |
452 		     V_TIMEOUT(200 * core_ticks_per_usec(adap)));
453 	t3_write_reg(adap, A_SG_HI_DRB_HI_THRSH,
454 		     adap->params.rev < T3_REV_C ? 1000 : 500);
455 	t3_write_reg(adap, A_SG_HI_DRB_LO_THRSH, 256);
456 	t3_write_reg(adap, A_SG_LO_DRB_HI_THRSH, 1000);
457 	t3_write_reg(adap, A_SG_LO_DRB_LO_THRSH, 256);
458 	t3_write_reg(adap, A_SG_OCO_BASE, V_BASE1(0xfff));
459 	t3_write_reg(adap, A_SG_DRB_PRI_THRESH, 63 * 1024);
460 }
461 
462 
463 /**
464  *	sgl_len - calculates the size of an SGL of the given capacity
465  *	@n: the number of SGL entries
466  *
467  *	Calculates the number of flits needed for a scatter/gather list that
468  *	can hold the given number of entries.
469  */
470 static __inline unsigned int
471 sgl_len(unsigned int n)
472 {
473 	return ((3 * n) / 2 + (n & 1));
474 }
475 
476 /**
477  *	get_imm_packet - return the next ingress packet buffer from a response
478  *	@resp: the response descriptor containing the packet data
479  *
480  *	Return a packet containing the immediate data of the given response.
481  */
482 static int
483 get_imm_packet(adapter_t *sc, const struct rsp_desc *resp, struct mbuf *m)
484 {
485 
486 	if (resp->rss_hdr.opcode == CPL_RX_DATA) {
487 		const struct cpl_rx_data *cpl = (const void *)&resp->imm_data[0];
488 		m->m_len = sizeof(*cpl) + ntohs(cpl->len);
489 	} else if (resp->rss_hdr.opcode == CPL_RX_PKT) {
490 		const struct cpl_rx_pkt *cpl = (const void *)&resp->imm_data[0];
491 		m->m_len = sizeof(*cpl) + ntohs(cpl->len);
492 	} else
493 		m->m_len = IMMED_PKT_SIZE;
494 	m->m_ext.ext_buf = NULL;
495 	m->m_ext.ext_type = 0;
496 	memcpy(mtod(m, uint8_t *), resp->imm_data, m->m_len);
497 	return (0);
498 }
499 
500 static __inline u_int
501 flits_to_desc(u_int n)
502 {
503 	return (flit_desc_map[n]);
504 }
505 
506 #define SGE_PARERR (F_CPPARITYERROR | F_OCPARITYERROR | F_RCPARITYERROR | \
507 		    F_IRPARITYERROR | V_ITPARITYERROR(M_ITPARITYERROR) | \
508 		    V_FLPARITYERROR(M_FLPARITYERROR) | F_LODRBPARITYERROR | \
509 		    F_HIDRBPARITYERROR | F_LORCQPARITYERROR | \
510 		    F_HIRCQPARITYERROR)
511 #define SGE_FRAMINGERR (F_UC_REQ_FRAMINGERROR | F_R_REQ_FRAMINGERROR)
512 #define SGE_FATALERR (SGE_PARERR | SGE_FRAMINGERR | F_RSPQCREDITOVERFOW | \
513 		      F_RSPQDISABLED)
514 
515 /**
516  *	t3_sge_err_intr_handler - SGE async event interrupt handler
517  *	@adapter: the adapter
518  *
519  *	Interrupt handler for SGE asynchronous (non-data) events.
520  */
521 void
522 t3_sge_err_intr_handler(adapter_t *adapter)
523 {
524 	unsigned int v, status;
525 
526 	status = t3_read_reg(adapter, A_SG_INT_CAUSE);
527 	if (status & SGE_PARERR)
528 		CH_ALERT(adapter, "SGE parity error (0x%x)\n",
529 			 status & SGE_PARERR);
530 	if (status & SGE_FRAMINGERR)
531 		CH_ALERT(adapter, "SGE framing error (0x%x)\n",
532 			 status & SGE_FRAMINGERR);
533 	if (status & F_RSPQCREDITOVERFOW)
534 		CH_ALERT(adapter, "SGE response queue credit overflow\n");
535 
536 	if (status & F_RSPQDISABLED) {
537 		v = t3_read_reg(adapter, A_SG_RSPQ_FL_STATUS);
538 
539 		CH_ALERT(adapter,
540 			 "packet delivered to disabled response queue (0x%x)\n",
541 			 (v >> S_RSPQ0DISABLED) & 0xff);
542 	}
543 
544 	t3_write_reg(adapter, A_SG_INT_CAUSE, status);
545 	if (status & SGE_FATALERR)
546 		t3_fatal_err(adapter);
547 }
548 
549 void
550 t3_sge_prep(adapter_t *adap, struct sge_params *p)
551 {
552 	int i, nqsets, fl_q_size, jumbo_q_size, use_16k, jumbo_buf_size;
553 
554 	nqsets = min(SGE_QSETS / adap->params.nports, mp_ncpus);
555 	nqsets *= adap->params.nports;
556 
557 	fl_q_size = min(nmbclusters/(3*nqsets), FL_Q_SIZE);
558 
559 	while (!powerof2(fl_q_size))
560 		fl_q_size--;
561 
562 	use_16k = cxgb_use_16k_clusters != -1 ? cxgb_use_16k_clusters :
563 	    is_offload(adap);
564 
565 	if (use_16k) {
566 		jumbo_q_size = min(nmbjumbo16/(3*nqsets), JUMBO_Q_SIZE);
567 		jumbo_buf_size = MJUM16BYTES;
568 	} else {
569 		jumbo_q_size = min(nmbjumbo9/(3*nqsets), JUMBO_Q_SIZE);
570 		jumbo_buf_size = MJUM9BYTES;
571 	}
572 	while (!powerof2(jumbo_q_size))
573 		jumbo_q_size--;
574 
575 	if (fl_q_size < (FL_Q_SIZE / 4) || jumbo_q_size < (JUMBO_Q_SIZE / 2))
576 		device_printf(adap->dev,
577 		    "Insufficient clusters and/or jumbo buffers.\n");
578 
579 	p->max_pkt_size = jumbo_buf_size - sizeof(struct cpl_rx_data);
580 
581 	for (i = 0; i < SGE_QSETS; ++i) {
582 		struct qset_params *q = p->qset + i;
583 
584 		if (adap->params.nports > 2) {
585 			q->coalesce_usecs = 50;
586 		} else {
587 #ifdef INVARIANTS
588 			q->coalesce_usecs = 10;
589 #else
590 			q->coalesce_usecs = 5;
591 #endif
592 		}
593 		q->polling = 0;
594 		q->rspq_size = RSPQ_Q_SIZE;
595 		q->fl_size = fl_q_size;
596 		q->jumbo_size = jumbo_q_size;
597 		q->jumbo_buf_size = jumbo_buf_size;
598 		q->txq_size[TXQ_ETH] = TX_ETH_Q_SIZE;
599 		q->txq_size[TXQ_OFLD] = is_offload(adap) ? TX_OFLD_Q_SIZE : 16;
600 		q->txq_size[TXQ_CTRL] = TX_CTRL_Q_SIZE;
601 		q->cong_thres = 0;
602 	}
603 }
604 
605 int
606 t3_sge_alloc(adapter_t *sc)
607 {
608 
609 	/* The parent tag. */
610 	if (bus_dma_tag_create( bus_get_dma_tag(sc->dev),/* PCI parent */
611 				1, 0,			/* algnmnt, boundary */
612 				BUS_SPACE_MAXADDR,	/* lowaddr */
613 				BUS_SPACE_MAXADDR,	/* highaddr */
614 				NULL, NULL,		/* filter, filterarg */
615 				BUS_SPACE_MAXSIZE_32BIT,/* maxsize */
616 				BUS_SPACE_UNRESTRICTED, /* nsegments */
617 				BUS_SPACE_MAXSIZE_32BIT,/* maxsegsize */
618 				0,			/* flags */
619 				NULL, NULL,		/* lock, lockarg */
620 				&sc->parent_dmat)) {
621 		device_printf(sc->dev, "Cannot allocate parent DMA tag\n");
622 		return (ENOMEM);
623 	}
624 
625 	/*
626 	 * DMA tag for normal sized RX frames
627 	 */
628 	if (bus_dma_tag_create(sc->parent_dmat, MCLBYTES, 0, BUS_SPACE_MAXADDR,
629 		BUS_SPACE_MAXADDR, NULL, NULL, MCLBYTES, 1,
630 		MCLBYTES, BUS_DMA_ALLOCNOW, NULL, NULL, &sc->rx_dmat)) {
631 		device_printf(sc->dev, "Cannot allocate RX DMA tag\n");
632 		return (ENOMEM);
633 	}
634 
635 	/*
636 	 * DMA tag for jumbo sized RX frames.
637 	 */
638 	if (bus_dma_tag_create(sc->parent_dmat, MJUM16BYTES, 0, BUS_SPACE_MAXADDR,
639 		BUS_SPACE_MAXADDR, NULL, NULL, MJUM16BYTES, 1, MJUM16BYTES,
640 		BUS_DMA_ALLOCNOW, NULL, NULL, &sc->rx_jumbo_dmat)) {
641 		device_printf(sc->dev, "Cannot allocate RX jumbo DMA tag\n");
642 		return (ENOMEM);
643 	}
644 
645 	/*
646 	 * DMA tag for TX frames.
647 	 */
648 	if (bus_dma_tag_create(sc->parent_dmat, 1, 0, BUS_SPACE_MAXADDR,
649 		BUS_SPACE_MAXADDR, NULL, NULL, TX_MAX_SIZE, TX_MAX_SEGS,
650 		TX_MAX_SIZE, BUS_DMA_ALLOCNOW,
651 		NULL, NULL, &sc->tx_dmat)) {
652 		device_printf(sc->dev, "Cannot allocate TX DMA tag\n");
653 		return (ENOMEM);
654 	}
655 
656 	return (0);
657 }
658 
659 int
660 t3_sge_free(struct adapter * sc)
661 {
662 
663 	if (sc->tx_dmat != NULL)
664 		bus_dma_tag_destroy(sc->tx_dmat);
665 
666 	if (sc->rx_jumbo_dmat != NULL)
667 		bus_dma_tag_destroy(sc->rx_jumbo_dmat);
668 
669 	if (sc->rx_dmat != NULL)
670 		bus_dma_tag_destroy(sc->rx_dmat);
671 
672 	if (sc->parent_dmat != NULL)
673 		bus_dma_tag_destroy(sc->parent_dmat);
674 
675 	return (0);
676 }
677 
678 void
679 t3_update_qset_coalesce(struct sge_qset *qs, const struct qset_params *p)
680 {
681 
682 	qs->rspq.holdoff_tmr = max(p->coalesce_usecs * 10, 1U);
683 	qs->rspq.polling = 0 /* p->polling */;
684 }
685 
686 #if !defined(__i386__) && !defined(__amd64__)
687 static void
688 refill_fl_cb(void *arg, bus_dma_segment_t *segs, int nseg, int error)
689 {
690 	struct refill_fl_cb_arg *cb_arg = arg;
691 
692 	cb_arg->error = error;
693 	cb_arg->seg = segs[0];
694 	cb_arg->nseg = nseg;
695 
696 }
697 #endif
698 /**
699  *	refill_fl - refill an SGE free-buffer list
700  *	@sc: the controller softc
701  *	@q: the free-list to refill
702  *	@n: the number of new buffers to allocate
703  *
704  *	(Re)populate an SGE free-buffer list with up to @n new packet buffers.
705  *	The caller must assure that @n does not exceed the queue's capacity.
706  */
707 static void
708 refill_fl(adapter_t *sc, struct sge_fl *q, int n)
709 {
710 	struct rx_sw_desc *sd = &q->sdesc[q->pidx];
711 	struct rx_desc *d = &q->desc[q->pidx];
712 	struct refill_fl_cb_arg cb_arg;
713 	struct mbuf *m;
714 	caddr_t cl;
715 	int err;
716 
717 	cb_arg.error = 0;
718 	while (n--) {
719 		/*
720 		 * We allocate an uninitialized mbuf + cluster, mbuf is
721 		 * initialized after rx.
722 		 */
723 		if (q->zone == zone_pack) {
724 			if ((m = m_getcl(M_NOWAIT, MT_NOINIT, M_PKTHDR)) == NULL)
725 				break;
726 			cl = m->m_ext.ext_buf;
727 		} else {
728 			if ((cl = m_cljget(NULL, M_NOWAIT, q->buf_size)) == NULL)
729 				break;
730 			if ((m = m_gethdr_raw(M_NOWAIT, 0)) == NULL) {
731 				uma_zfree(q->zone, cl);
732 				break;
733 			}
734 		}
735 		if ((sd->flags & RX_SW_DESC_MAP_CREATED) == 0) {
736 			if ((err = bus_dmamap_create(q->entry_tag, 0, &sd->map))) {
737 				log(LOG_WARNING, "bus_dmamap_create failed %d\n", err);
738 				uma_zfree(q->zone, cl);
739 				goto done;
740 			}
741 			sd->flags |= RX_SW_DESC_MAP_CREATED;
742 		}
743 #if !defined(__i386__) && !defined(__amd64__)
744 		err = bus_dmamap_load(q->entry_tag, sd->map,
745 		    cl, q->buf_size, refill_fl_cb, &cb_arg, 0);
746 
747 		if (err != 0 || cb_arg.error) {
748 			if (q->zone != zone_pack)
749 				uma_zfree(q->zone, cl);
750 			m_free(m);
751 			goto done;
752 		}
753 #else
754 		cb_arg.seg.ds_addr = pmap_kextract((vm_offset_t)cl);
755 #endif
756 		sd->flags |= RX_SW_DESC_INUSE;
757 		sd->rxsd_cl = cl;
758 		sd->m = m;
759 		d->addr_lo = htobe32(cb_arg.seg.ds_addr & 0xffffffff);
760 		d->addr_hi = htobe32(((uint64_t)cb_arg.seg.ds_addr >>32) & 0xffffffff);
761 		d->len_gen = htobe32(V_FLD_GEN1(q->gen));
762 		d->gen2 = htobe32(V_FLD_GEN2(q->gen));
763 
764 		d++;
765 		sd++;
766 
767 		if (++q->pidx == q->size) {
768 			q->pidx = 0;
769 			q->gen ^= 1;
770 			sd = q->sdesc;
771 			d = q->desc;
772 		}
773 		q->credits++;
774 		q->db_pending++;
775 	}
776 
777 done:
778 	if (q->db_pending >= 32) {
779 		q->db_pending = 0;
780 		t3_write_reg(sc, A_SG_KDOORBELL, V_EGRCNTX(q->cntxt_id));
781 	}
782 }
783 
784 
785 /**
786  *	free_rx_bufs - free the Rx buffers on an SGE free list
787  *	@sc: the controle softc
788  *	@q: the SGE free list to clean up
789  *
790  *	Release the buffers on an SGE free-buffer Rx queue.  HW fetching from
791  *	this queue should be stopped before calling this function.
792  */
793 static void
794 free_rx_bufs(adapter_t *sc, struct sge_fl *q)
795 {
796 	u_int cidx = q->cidx;
797 
798 	while (q->credits--) {
799 		struct rx_sw_desc *d = &q->sdesc[cidx];
800 
801 		if (d->flags & RX_SW_DESC_INUSE) {
802 			bus_dmamap_unload(q->entry_tag, d->map);
803 			bus_dmamap_destroy(q->entry_tag, d->map);
804 			if (q->zone == zone_pack) {
805 				m_init(d->m, M_NOWAIT, MT_DATA, M_EXT);
806 				uma_zfree(zone_pack, d->m);
807 			} else {
808 				m_init(d->m, M_NOWAIT, MT_DATA, 0);
809 				m_free_raw(d->m);
810 				uma_zfree(q->zone, d->rxsd_cl);
811 			}
812 		}
813 
814 		d->rxsd_cl = NULL;
815 		d->m = NULL;
816 		if (++cidx == q->size)
817 			cidx = 0;
818 	}
819 }
820 
821 static __inline void
822 __refill_fl(adapter_t *adap, struct sge_fl *fl)
823 {
824 	refill_fl(adap, fl, min(16U, fl->size - fl->credits));
825 }
826 
827 static __inline void
828 __refill_fl_lt(adapter_t *adap, struct sge_fl *fl, int max)
829 {
830 	uint32_t reclaimable = fl->size - fl->credits;
831 
832 	if (reclaimable > 0)
833 		refill_fl(adap, fl, min(max, reclaimable));
834 }
835 
836 /**
837  *	recycle_rx_buf - recycle a receive buffer
838  *	@adapter: the adapter
839  *	@q: the SGE free list
840  *	@idx: index of buffer to recycle
841  *
842  *	Recycles the specified buffer on the given free list by adding it at
843  *	the next available slot on the list.
844  */
845 static void
846 recycle_rx_buf(adapter_t *adap, struct sge_fl *q, unsigned int idx)
847 {
848 	struct rx_desc *from = &q->desc[idx];
849 	struct rx_desc *to   = &q->desc[q->pidx];
850 
851 	q->sdesc[q->pidx] = q->sdesc[idx];
852 	to->addr_lo = from->addr_lo;        // already big endian
853 	to->addr_hi = from->addr_hi;        // likewise
854 	wmb();	/* necessary ? */
855 	to->len_gen = htobe32(V_FLD_GEN1(q->gen));
856 	to->gen2 = htobe32(V_FLD_GEN2(q->gen));
857 	q->credits++;
858 
859 	if (++q->pidx == q->size) {
860 		q->pidx = 0;
861 		q->gen ^= 1;
862 	}
863 	t3_write_reg(adap, A_SG_KDOORBELL, V_EGRCNTX(q->cntxt_id));
864 }
865 
866 static void
867 alloc_ring_cb(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
868 {
869 	uint32_t *addr;
870 
871 	addr = arg;
872 	*addr = segs[0].ds_addr;
873 }
874 
875 static int
876 alloc_ring(adapter_t *sc, size_t nelem, size_t elem_size, size_t sw_size,
877     bus_addr_t *phys, void *desc, void *sdesc, bus_dma_tag_t *tag,
878     bus_dmamap_t *map, bus_dma_tag_t parent_entry_tag, bus_dma_tag_t *entry_tag)
879 {
880 	size_t len = nelem * elem_size;
881 	void *s = NULL;
882 	void *p = NULL;
883 	int err;
884 
885 	if ((err = bus_dma_tag_create(sc->parent_dmat, PAGE_SIZE, 0,
886 				      BUS_SPACE_MAXADDR_32BIT,
887 				      BUS_SPACE_MAXADDR, NULL, NULL, len, 1,
888 				      len, 0, NULL, NULL, tag)) != 0) {
889 		device_printf(sc->dev, "Cannot allocate descriptor tag\n");
890 		return (ENOMEM);
891 	}
892 
893 	if ((err = bus_dmamem_alloc(*tag, (void **)&p, BUS_DMA_NOWAIT,
894 				    map)) != 0) {
895 		device_printf(sc->dev, "Cannot allocate descriptor memory\n");
896 		return (ENOMEM);
897 	}
898 
899 	bus_dmamap_load(*tag, *map, p, len, alloc_ring_cb, phys, 0);
900 	bzero(p, len);
901 	*(void **)desc = p;
902 
903 	if (sw_size) {
904 		len = nelem * sw_size;
905 		s = malloc(len, M_DEVBUF, M_WAITOK|M_ZERO);
906 		*(void **)sdesc = s;
907 	}
908 	if (parent_entry_tag == NULL)
909 		return (0);
910 
911 	if ((err = bus_dma_tag_create(parent_entry_tag, 1, 0,
912 				      BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR,
913 		                      NULL, NULL, TX_MAX_SIZE, TX_MAX_SEGS,
914 				      TX_MAX_SIZE, BUS_DMA_ALLOCNOW,
915 		                      NULL, NULL, entry_tag)) != 0) {
916 		device_printf(sc->dev, "Cannot allocate descriptor entry tag\n");
917 		return (ENOMEM);
918 	}
919 	return (0);
920 }
921 
922 static void
923 sge_slow_intr_handler(void *arg, int ncount)
924 {
925 	adapter_t *sc = arg;
926 
927 	t3_slow_intr_handler(sc);
928 	t3_write_reg(sc, A_PL_INT_ENABLE0, sc->slow_intr_mask);
929 	(void) t3_read_reg(sc, A_PL_INT_ENABLE0);
930 }
931 
932 /**
933  *	sge_timer_cb - perform periodic maintenance of an SGE qset
934  *	@data: the SGE queue set to maintain
935  *
936  *	Runs periodically from a timer to perform maintenance of an SGE queue
937  *	set.  It performs two tasks:
938  *
939  *	a) Cleans up any completed Tx descriptors that may still be pending.
940  *	Normal descriptor cleanup happens when new packets are added to a Tx
941  *	queue so this timer is relatively infrequent and does any cleanup only
942  *	if the Tx queue has not seen any new packets in a while.  We make a
943  *	best effort attempt to reclaim descriptors, in that we don't wait
944  *	around if we cannot get a queue's lock (which most likely is because
945  *	someone else is queueing new packets and so will also handle the clean
946  *	up).  Since control queues use immediate data exclusively we don't
947  *	bother cleaning them up here.
948  *
949  *	b) Replenishes Rx queues that have run out due to memory shortage.
950  *	Normally new Rx buffers are added when existing ones are consumed but
951  *	when out of memory a queue can become empty.  We try to add only a few
952  *	buffers here, the queue will be replenished fully as these new buffers
953  *	are used up if memory shortage has subsided.
954  *
955  *	c) Return coalesced response queue credits in case a response queue is
956  *	starved.
957  *
958  *	d) Ring doorbells for T304 tunnel queues since we have seen doorbell
959  *	fifo overflows and the FW doesn't implement any recovery scheme yet.
960  */
961 static void
962 sge_timer_cb(void *arg)
963 {
964 	adapter_t *sc = arg;
965 	if ((sc->flags & USING_MSIX) == 0) {
966 
967 		struct port_info *pi;
968 		struct sge_qset *qs;
969 		struct sge_txq  *txq;
970 		int i, j;
971 		int reclaim_ofl, refill_rx;
972 
973 		if (sc->open_device_map == 0)
974 			return;
975 
976 		for (i = 0; i < sc->params.nports; i++) {
977 			pi = &sc->port[i];
978 			for (j = 0; j < pi->nqsets; j++) {
979 				qs = &sc->sge.qs[pi->first_qset + j];
980 				txq = &qs->txq[0];
981 				reclaim_ofl = txq[TXQ_OFLD].processed - txq[TXQ_OFLD].cleaned;
982 				refill_rx = ((qs->fl[0].credits < qs->fl[0].size) ||
983 				    (qs->fl[1].credits < qs->fl[1].size));
984 				if (reclaim_ofl || refill_rx) {
985 					taskqueue_enqueue(sc->tq, &pi->timer_reclaim_task);
986 					break;
987 				}
988 			}
989 		}
990 	}
991 
992 	if (sc->params.nports > 2) {
993 		int i;
994 
995 		for_each_port(sc, i) {
996 			struct port_info *pi = &sc->port[i];
997 
998 			t3_write_reg(sc, A_SG_KDOORBELL,
999 				     F_SELEGRCNTX |
1000 				     (FW_TUNNEL_SGEEC_START + pi->first_qset));
1001 		}
1002 	}
1003 	if (((sc->flags & USING_MSIX) == 0 || sc->params.nports > 2) &&
1004 	    sc->open_device_map != 0)
1005 		callout_reset(&sc->sge_timer_ch, TX_RECLAIM_PERIOD, sge_timer_cb, sc);
1006 }
1007 
1008 /*
1009  * This is meant to be a catch-all function to keep sge state private
1010  * to sge.c
1011  *
1012  */
1013 int
1014 t3_sge_init_adapter(adapter_t *sc)
1015 {
1016 	callout_init(&sc->sge_timer_ch, 1);
1017 	callout_reset(&sc->sge_timer_ch, TX_RECLAIM_PERIOD, sge_timer_cb, sc);
1018 	TASK_INIT(&sc->slow_intr_task, 0, sge_slow_intr_handler, sc);
1019 	return (0);
1020 }
1021 
1022 int
1023 t3_sge_reset_adapter(adapter_t *sc)
1024 {
1025 	callout_reset(&sc->sge_timer_ch, TX_RECLAIM_PERIOD, sge_timer_cb, sc);
1026 	return (0);
1027 }
1028 
1029 int
1030 t3_sge_init_port(struct port_info *pi)
1031 {
1032 	TASK_INIT(&pi->timer_reclaim_task, 0, sge_timer_reclaim, pi);
1033 	return (0);
1034 }
1035 
1036 /**
1037  *	refill_rspq - replenish an SGE response queue
1038  *	@adapter: the adapter
1039  *	@q: the response queue to replenish
1040  *	@credits: how many new responses to make available
1041  *
1042  *	Replenishes a response queue by making the supplied number of responses
1043  *	available to HW.
1044  */
1045 static __inline void
1046 refill_rspq(adapter_t *sc, const struct sge_rspq *q, u_int credits)
1047 {
1048 
1049 	/* mbufs are allocated on demand when a rspq entry is processed. */
1050 	t3_write_reg(sc, A_SG_RSPQ_CREDIT_RETURN,
1051 		     V_RSPQ(q->cntxt_id) | V_CREDITS(credits));
1052 }
1053 
1054 static void
1055 sge_txq_reclaim_handler(void *arg, int ncount)
1056 {
1057 	struct sge_qset *qs = arg;
1058 	int i;
1059 
1060 	for (i = 0; i < 3; i++)
1061 		reclaim_completed_tx(qs, 16, i);
1062 }
1063 
1064 static void
1065 sge_timer_reclaim(void *arg, int ncount)
1066 {
1067 	struct port_info *pi = arg;
1068 	int i, nqsets = pi->nqsets;
1069 	adapter_t *sc = pi->adapter;
1070 	struct sge_qset *qs;
1071 	struct mtx *lock;
1072 
1073 	KASSERT((sc->flags & USING_MSIX) == 0,
1074 	    ("can't call timer reclaim for msi-x"));
1075 
1076 	for (i = 0; i < nqsets; i++) {
1077 		qs = &sc->sge.qs[pi->first_qset + i];
1078 
1079 		reclaim_completed_tx(qs, 16, TXQ_OFLD);
1080 		lock = (sc->flags & USING_MSIX) ? &qs->rspq.lock :
1081 			    &sc->sge.qs[0].rspq.lock;
1082 
1083 		if (mtx_trylock(lock)) {
1084 			/* XXX currently assume that we are *NOT* polling */
1085 			uint32_t status = t3_read_reg(sc, A_SG_RSPQ_FL_STATUS);
1086 
1087 			if (qs->fl[0].credits < qs->fl[0].size - 16)
1088 				__refill_fl(sc, &qs->fl[0]);
1089 			if (qs->fl[1].credits < qs->fl[1].size - 16)
1090 				__refill_fl(sc, &qs->fl[1]);
1091 
1092 			if (status & (1 << qs->rspq.cntxt_id)) {
1093 				if (qs->rspq.credits) {
1094 					refill_rspq(sc, &qs->rspq, 1);
1095 					qs->rspq.credits--;
1096 					t3_write_reg(sc, A_SG_RSPQ_FL_STATUS,
1097 					    1 << qs->rspq.cntxt_id);
1098 				}
1099 			}
1100 			mtx_unlock(lock);
1101 		}
1102 	}
1103 }
1104 
1105 /**
1106  *	init_qset_cntxt - initialize an SGE queue set context info
1107  *	@qs: the queue set
1108  *	@id: the queue set id
1109  *
1110  *	Initializes the TIDs and context ids for the queues of a queue set.
1111  */
1112 static void
1113 init_qset_cntxt(struct sge_qset *qs, u_int id)
1114 {
1115 
1116 	qs->rspq.cntxt_id = id;
1117 	qs->fl[0].cntxt_id = 2 * id;
1118 	qs->fl[1].cntxt_id = 2 * id + 1;
1119 	qs->txq[TXQ_ETH].cntxt_id = FW_TUNNEL_SGEEC_START + id;
1120 	qs->txq[TXQ_ETH].token = FW_TUNNEL_TID_START + id;
1121 	qs->txq[TXQ_OFLD].cntxt_id = FW_OFLD_SGEEC_START + id;
1122 	qs->txq[TXQ_CTRL].cntxt_id = FW_CTRL_SGEEC_START + id;
1123 	qs->txq[TXQ_CTRL].token = FW_CTRL_TID_START + id;
1124 
1125 	/* XXX: a sane limit is needed instead of INT_MAX */
1126 	mbufq_init(&qs->txq[TXQ_ETH].sendq, INT_MAX);
1127 	mbufq_init(&qs->txq[TXQ_OFLD].sendq, INT_MAX);
1128 	mbufq_init(&qs->txq[TXQ_CTRL].sendq, INT_MAX);
1129 }
1130 
1131 
1132 static void
1133 txq_prod(struct sge_txq *txq, unsigned int ndesc, struct txq_state *txqs)
1134 {
1135 	txq->in_use += ndesc;
1136 	/*
1137 	 * XXX we don't handle stopping of queue
1138 	 * presumably start handles this when we bump against the end
1139 	 */
1140 	txqs->gen = txq->gen;
1141 	txq->unacked += ndesc;
1142 	txqs->compl = (txq->unacked & 32) << (S_WR_COMPL - 5);
1143 	txq->unacked &= 31;
1144 	txqs->pidx = txq->pidx;
1145 	txq->pidx += ndesc;
1146 #ifdef INVARIANTS
1147 	if (((txqs->pidx > txq->cidx) &&
1148 		(txq->pidx < txqs->pidx) &&
1149 		(txq->pidx >= txq->cidx)) ||
1150 	    ((txqs->pidx < txq->cidx) &&
1151 		(txq->pidx >= txq-> cidx)) ||
1152 	    ((txqs->pidx < txq->cidx) &&
1153 		(txq->cidx < txqs->pidx)))
1154 		panic("txqs->pidx=%d txq->pidx=%d txq->cidx=%d",
1155 		    txqs->pidx, txq->pidx, txq->cidx);
1156 #endif
1157 	if (txq->pidx >= txq->size) {
1158 		txq->pidx -= txq->size;
1159 		txq->gen ^= 1;
1160 	}
1161 
1162 }
1163 
1164 /**
1165  *	calc_tx_descs - calculate the number of Tx descriptors for a packet
1166  *	@m: the packet mbufs
1167  *      @nsegs: the number of segments
1168  *
1169  * 	Returns the number of Tx descriptors needed for the given Ethernet
1170  * 	packet.  Ethernet packets require addition of WR and CPL headers.
1171  */
1172 static __inline unsigned int
1173 calc_tx_descs(const struct mbuf *m, int nsegs)
1174 {
1175 	unsigned int flits;
1176 
1177 	if (m->m_pkthdr.len <= PIO_LEN)
1178 		return 1;
1179 
1180 	flits = sgl_len(nsegs) + 2;
1181 	if (m->m_pkthdr.csum_flags & CSUM_TSO)
1182 		flits++;
1183 
1184 	return flits_to_desc(flits);
1185 }
1186 
1187 /**
1188  *	make_sgl - populate a scatter/gather list for a packet
1189  *	@sgp: the SGL to populate
1190  *	@segs: the packet dma segments
1191  *	@nsegs: the number of segments
1192  *
1193  *	Generates a scatter/gather list for the buffers that make up a packet
1194  *	and returns the SGL size in 8-byte words.  The caller must size the SGL
1195  *	appropriately.
1196  */
1197 static __inline void
1198 make_sgl(struct sg_ent *sgp, bus_dma_segment_t *segs, int nsegs)
1199 {
1200 	int i, idx;
1201 
1202 	for (idx = 0, i = 0; i < nsegs; i++) {
1203 		/*
1204 		 * firmware doesn't like empty segments
1205 		 */
1206 		if (segs[i].ds_len == 0)
1207 			continue;
1208 		if (i && idx == 0)
1209 			++sgp;
1210 
1211 		sgp->len[idx] = htobe32(segs[i].ds_len);
1212 		sgp->addr[idx] = htobe64(segs[i].ds_addr);
1213 		idx ^= 1;
1214 	}
1215 
1216 	if (idx) {
1217 		sgp->len[idx] = 0;
1218 		sgp->addr[idx] = 0;
1219 	}
1220 }
1221 
1222 /**
1223  *	check_ring_tx_db - check and potentially ring a Tx queue's doorbell
1224  *	@adap: the adapter
1225  *	@q: the Tx queue
1226  *
1227  *	Ring the doorbell if a Tx queue is asleep.  There is a natural race,
1228  *	where the HW is going to sleep just after we checked, however,
1229  *	then the interrupt handler will detect the outstanding TX packet
1230  *	and ring the doorbell for us.
1231  *
1232  *	When GTS is disabled we unconditionally ring the doorbell.
1233  */
1234 static __inline void
1235 check_ring_tx_db(adapter_t *adap, struct sge_txq *q, int mustring)
1236 {
1237 #if USE_GTS
1238 	clear_bit(TXQ_LAST_PKT_DB, &q->flags);
1239 	if (test_and_set_bit(TXQ_RUNNING, &q->flags) == 0) {
1240 		set_bit(TXQ_LAST_PKT_DB, &q->flags);
1241 #ifdef T3_TRACE
1242 		T3_TRACE1(adap->tb[q->cntxt_id & 7], "doorbell Tx, cntxt %d",
1243 			  q->cntxt_id);
1244 #endif
1245 		t3_write_reg(adap, A_SG_KDOORBELL,
1246 			     F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id));
1247 	}
1248 #else
1249 	if (mustring || ++q->db_pending >= 32) {
1250 		wmb();            /* write descriptors before telling HW */
1251 		t3_write_reg(adap, A_SG_KDOORBELL,
1252 		    F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id));
1253 		q->db_pending = 0;
1254 	}
1255 #endif
1256 }
1257 
1258 static __inline void
1259 wr_gen2(struct tx_desc *d, unsigned int gen)
1260 {
1261 #if SGE_NUM_GENBITS == 2
1262 	d->flit[TX_DESC_FLITS - 1] = htobe64(gen);
1263 #endif
1264 }
1265 
1266 /**
1267  *	write_wr_hdr_sgl - write a WR header and, optionally, SGL
1268  *	@ndesc: number of Tx descriptors spanned by the SGL
1269  *	@txd: first Tx descriptor to be written
1270  *	@txqs: txq state (generation and producer index)
1271  *	@txq: the SGE Tx queue
1272  *	@sgl: the SGL
1273  *	@flits: number of flits to the start of the SGL in the first descriptor
1274  *	@sgl_flits: the SGL size in flits
1275  *	@wr_hi: top 32 bits of WR header based on WR type (big endian)
1276  *	@wr_lo: low 32 bits of WR header based on WR type (big endian)
1277  *
1278  *	Write a work request header and an associated SGL.  If the SGL is
1279  *	small enough to fit into one Tx descriptor it has already been written
1280  *	and we just need to write the WR header.  Otherwise we distribute the
1281  *	SGL across the number of descriptors it spans.
1282  */
1283 static void
1284 write_wr_hdr_sgl(unsigned int ndesc, struct tx_desc *txd, struct txq_state *txqs,
1285     const struct sge_txq *txq, const struct sg_ent *sgl, unsigned int flits,
1286     unsigned int sgl_flits, unsigned int wr_hi, unsigned int wr_lo)
1287 {
1288 
1289 	struct work_request_hdr *wrp = (struct work_request_hdr *)txd;
1290 	struct tx_sw_desc *txsd = &txq->sdesc[txqs->pidx];
1291 
1292 	if (__predict_true(ndesc == 1)) {
1293 		set_wr_hdr(wrp, htonl(F_WR_SOP | F_WR_EOP | V_WR_DATATYPE(1) |
1294 		    V_WR_SGLSFLT(flits)) | wr_hi,
1295 		    htonl(V_WR_LEN(flits + sgl_flits) | V_WR_GEN(txqs->gen)) |
1296 		    wr_lo);
1297 
1298 		wr_gen2(txd, txqs->gen);
1299 
1300 	} else {
1301 		unsigned int ogen = txqs->gen;
1302 		const uint64_t *fp = (const uint64_t *)sgl;
1303 		struct work_request_hdr *wp = wrp;
1304 
1305 		wrp->wrh_hi = htonl(F_WR_SOP | V_WR_DATATYPE(1) |
1306 		    V_WR_SGLSFLT(flits)) | wr_hi;
1307 
1308 		while (sgl_flits) {
1309 			unsigned int avail = WR_FLITS - flits;
1310 
1311 			if (avail > sgl_flits)
1312 				avail = sgl_flits;
1313 			memcpy(&txd->flit[flits], fp, avail * sizeof(*fp));
1314 			sgl_flits -= avail;
1315 			ndesc--;
1316 			if (!sgl_flits)
1317 				break;
1318 
1319 			fp += avail;
1320 			txd++;
1321 			txsd++;
1322 			if (++txqs->pidx == txq->size) {
1323 				txqs->pidx = 0;
1324 				txqs->gen ^= 1;
1325 				txd = txq->desc;
1326 				txsd = txq->sdesc;
1327 			}
1328 
1329 			/*
1330 			 * when the head of the mbuf chain
1331 			 * is freed all clusters will be freed
1332 			 * with it
1333 			 */
1334 			wrp = (struct work_request_hdr *)txd;
1335 			wrp->wrh_hi = htonl(V_WR_DATATYPE(1) |
1336 			    V_WR_SGLSFLT(1)) | wr_hi;
1337 			wrp->wrh_lo = htonl(V_WR_LEN(min(WR_FLITS,
1338 				    sgl_flits + 1)) |
1339 			    V_WR_GEN(txqs->gen)) | wr_lo;
1340 			wr_gen2(txd, txqs->gen);
1341 			flits = 1;
1342 		}
1343 		wrp->wrh_hi |= htonl(F_WR_EOP);
1344 		wmb();
1345 		wp->wrh_lo = htonl(V_WR_LEN(WR_FLITS) | V_WR_GEN(ogen)) | wr_lo;
1346 		wr_gen2((struct tx_desc *)wp, ogen);
1347 	}
1348 }
1349 
1350 /* sizeof(*eh) + sizeof(*ip) + sizeof(*tcp) */
1351 #define TCPPKTHDRSIZE (ETHER_HDR_LEN + 20 + 20)
1352 
1353 #define GET_VTAG(cntrl, m) \
1354 do { \
1355 	if ((m)->m_flags & M_VLANTAG)					            \
1356 		cntrl |= F_TXPKT_VLAN_VLD | V_TXPKT_VLAN((m)->m_pkthdr.ether_vtag); \
1357 } while (0)
1358 
1359 static int
1360 t3_encap(struct sge_qset *qs, struct mbuf **m)
1361 {
1362 	adapter_t *sc;
1363 	struct mbuf *m0;
1364 	struct sge_txq *txq;
1365 	struct txq_state txqs;
1366 	struct port_info *pi;
1367 	unsigned int ndesc, flits, cntrl, mlen;
1368 	int err, nsegs, tso_info = 0;
1369 
1370 	struct work_request_hdr *wrp;
1371 	struct tx_sw_desc *txsd;
1372 	struct sg_ent *sgp, *sgl;
1373 	uint32_t wr_hi, wr_lo, sgl_flits;
1374 	bus_dma_segment_t segs[TX_MAX_SEGS];
1375 
1376 	struct tx_desc *txd;
1377 
1378 	pi = qs->port;
1379 	sc = pi->adapter;
1380 	txq = &qs->txq[TXQ_ETH];
1381 	txd = &txq->desc[txq->pidx];
1382 	txsd = &txq->sdesc[txq->pidx];
1383 	sgl = txq->txq_sgl;
1384 
1385 	prefetch(txd);
1386 	m0 = *m;
1387 
1388 	mtx_assert(&qs->lock, MA_OWNED);
1389 	cntrl = V_TXPKT_INTF(pi->txpkt_intf);
1390 	KASSERT(m0->m_flags & M_PKTHDR, ("not packet header\n"));
1391 
1392 	if  (m0->m_nextpkt == NULL && m0->m_next != NULL &&
1393 	    m0->m_pkthdr.csum_flags & (CSUM_TSO))
1394 		tso_info = V_LSO_MSS(m0->m_pkthdr.tso_segsz);
1395 
1396 	if (m0->m_nextpkt != NULL) {
1397 		busdma_map_sg_vec(txq->entry_tag, txsd->map, m0, segs, &nsegs);
1398 		ndesc = 1;
1399 		mlen = 0;
1400 	} else {
1401 		if ((err = busdma_map_sg_collapse(txq->entry_tag, txsd->map,
1402 		    &m0, segs, &nsegs))) {
1403 			if (cxgb_debug)
1404 				printf("failed ... err=%d\n", err);
1405 			return (err);
1406 		}
1407 		mlen = m0->m_pkthdr.len;
1408 		ndesc = calc_tx_descs(m0, nsegs);
1409 	}
1410 	txq_prod(txq, ndesc, &txqs);
1411 
1412 	KASSERT(m0->m_pkthdr.len, ("empty packet nsegs=%d", nsegs));
1413 	txsd->m = m0;
1414 
1415 	if (m0->m_nextpkt != NULL) {
1416 		struct cpl_tx_pkt_batch *cpl_batch = (struct cpl_tx_pkt_batch *)txd;
1417 		int i, fidx;
1418 
1419 		if (nsegs > 7)
1420 			panic("trying to coalesce %d packets in to one WR", nsegs);
1421 		txq->txq_coalesced += nsegs;
1422 		wrp = (struct work_request_hdr *)txd;
1423 		flits = nsegs*2 + 1;
1424 
1425 		for (fidx = 1, i = 0; i < nsegs; i++, fidx += 2) {
1426 			struct cpl_tx_pkt_batch_entry *cbe;
1427 			uint64_t flit;
1428 			uint32_t *hflit = (uint32_t *)&flit;
1429 			int cflags = m0->m_pkthdr.csum_flags;
1430 
1431 			cntrl = V_TXPKT_INTF(pi->txpkt_intf);
1432 			GET_VTAG(cntrl, m0);
1433 			cntrl |= V_TXPKT_OPCODE(CPL_TX_PKT);
1434 			if (__predict_false(!(cflags & CSUM_IP)))
1435 				cntrl |= F_TXPKT_IPCSUM_DIS;
1436 			if (__predict_false(!(cflags & (CSUM_TCP | CSUM_UDP |
1437 			    CSUM_UDP_IPV6 | CSUM_TCP_IPV6))))
1438 				cntrl |= F_TXPKT_L4CSUM_DIS;
1439 
1440 			hflit[0] = htonl(cntrl);
1441 			hflit[1] = htonl(segs[i].ds_len | 0x80000000);
1442 			flit |= htobe64(1 << 24);
1443 			cbe = &cpl_batch->pkt_entry[i];
1444 			cbe->cntrl = hflit[0];
1445 			cbe->len = hflit[1];
1446 			cbe->addr = htobe64(segs[i].ds_addr);
1447 		}
1448 
1449 		wr_hi = htonl(F_WR_SOP | F_WR_EOP | V_WR_DATATYPE(1) |
1450 		    V_WR_SGLSFLT(flits)) |
1451 		    htonl(V_WR_OP(FW_WROPCODE_TUNNEL_TX_PKT) | txqs.compl);
1452 		wr_lo = htonl(V_WR_LEN(flits) |
1453 		    V_WR_GEN(txqs.gen)) | htonl(V_WR_TID(txq->token));
1454 		set_wr_hdr(wrp, wr_hi, wr_lo);
1455 		wmb();
1456 		ETHER_BPF_MTAP(pi->ifp, m0);
1457 		wr_gen2(txd, txqs.gen);
1458 		check_ring_tx_db(sc, txq, 0);
1459 		return (0);
1460 	} else if (tso_info) {
1461 		uint16_t eth_type;
1462 		struct cpl_tx_pkt_lso *hdr = (struct cpl_tx_pkt_lso *)txd;
1463 		struct ether_header *eh;
1464 		void *l3hdr;
1465 		struct tcphdr *tcp;
1466 
1467 		txd->flit[2] = 0;
1468 		GET_VTAG(cntrl, m0);
1469 		cntrl |= V_TXPKT_OPCODE(CPL_TX_PKT_LSO);
1470 		hdr->cntrl = htonl(cntrl);
1471 		hdr->len = htonl(mlen | 0x80000000);
1472 
1473 		if (__predict_false(mlen < TCPPKTHDRSIZE)) {
1474 			printf("mbuf=%p,len=%d,tso_segsz=%d,csum_flags=%b,flags=%#x",
1475 			    m0, mlen, m0->m_pkthdr.tso_segsz,
1476 			    (int)m0->m_pkthdr.csum_flags, CSUM_BITS, m0->m_flags);
1477 			panic("tx tso packet too small");
1478 		}
1479 
1480 		/* Make sure that ether, ip, tcp headers are all in m0 */
1481 		if (__predict_false(m0->m_len < TCPPKTHDRSIZE)) {
1482 			m0 = m_pullup(m0, TCPPKTHDRSIZE);
1483 			if (__predict_false(m0 == NULL)) {
1484 				/* XXX panic probably an overreaction */
1485 				panic("couldn't fit header into mbuf");
1486 			}
1487 		}
1488 
1489 		eh = mtod(m0, struct ether_header *);
1490 		eth_type = eh->ether_type;
1491 		if (eth_type == htons(ETHERTYPE_VLAN)) {
1492 			struct ether_vlan_header *evh = (void *)eh;
1493 
1494 			tso_info |= V_LSO_ETH_TYPE(CPL_ETH_II_VLAN);
1495 			l3hdr = evh + 1;
1496 			eth_type = evh->evl_proto;
1497 		} else {
1498 			tso_info |= V_LSO_ETH_TYPE(CPL_ETH_II);
1499 			l3hdr = eh + 1;
1500 		}
1501 
1502 		if (eth_type == htons(ETHERTYPE_IP)) {
1503 			struct ip *ip = l3hdr;
1504 
1505 			tso_info |= V_LSO_IPHDR_WORDS(ip->ip_hl);
1506 			tcp = (struct tcphdr *)(ip + 1);
1507 		} else if (eth_type == htons(ETHERTYPE_IPV6)) {
1508 			struct ip6_hdr *ip6 = l3hdr;
1509 
1510 			KASSERT(ip6->ip6_nxt == IPPROTO_TCP,
1511 			    ("%s: CSUM_TSO with ip6_nxt %d",
1512 			    __func__, ip6->ip6_nxt));
1513 
1514 			tso_info |= F_LSO_IPV6;
1515 			tso_info |= V_LSO_IPHDR_WORDS(sizeof(*ip6) >> 2);
1516 			tcp = (struct tcphdr *)(ip6 + 1);
1517 		} else
1518 			panic("%s: CSUM_TSO but neither ip nor ip6", __func__);
1519 
1520 		tso_info |= V_LSO_TCPHDR_WORDS(tcp->th_off);
1521 		hdr->lso_info = htonl(tso_info);
1522 
1523 		if (__predict_false(mlen <= PIO_LEN)) {
1524 			/*
1525 			 * pkt not undersized but fits in PIO_LEN
1526 			 * Indicates a TSO bug at the higher levels.
1527 			 */
1528 			txsd->m = NULL;
1529 			m_copydata(m0, 0, mlen, (caddr_t)&txd->flit[3]);
1530 			flits = (mlen + 7) / 8 + 3;
1531 			wr_hi = htonl(V_WR_BCNTLFLT(mlen & 7) |
1532 					  V_WR_OP(FW_WROPCODE_TUNNEL_TX_PKT) |
1533 					  F_WR_SOP | F_WR_EOP | txqs.compl);
1534 			wr_lo = htonl(V_WR_LEN(flits) |
1535 			    V_WR_GEN(txqs.gen) | V_WR_TID(txq->token));
1536 			set_wr_hdr(&hdr->wr, wr_hi, wr_lo);
1537 			wmb();
1538 			ETHER_BPF_MTAP(pi->ifp, m0);
1539 			wr_gen2(txd, txqs.gen);
1540 			check_ring_tx_db(sc, txq, 0);
1541 			m_freem(m0);
1542 			return (0);
1543 		}
1544 		flits = 3;
1545 	} else {
1546 		struct cpl_tx_pkt *cpl = (struct cpl_tx_pkt *)txd;
1547 
1548 		GET_VTAG(cntrl, m0);
1549 		cntrl |= V_TXPKT_OPCODE(CPL_TX_PKT);
1550 		if (__predict_false(!(m0->m_pkthdr.csum_flags & CSUM_IP)))
1551 			cntrl |= F_TXPKT_IPCSUM_DIS;
1552 		if (__predict_false(!(m0->m_pkthdr.csum_flags & (CSUM_TCP |
1553 		    CSUM_UDP | CSUM_UDP_IPV6 | CSUM_TCP_IPV6))))
1554 			cntrl |= F_TXPKT_L4CSUM_DIS;
1555 		cpl->cntrl = htonl(cntrl);
1556 		cpl->len = htonl(mlen | 0x80000000);
1557 
1558 		if (mlen <= PIO_LEN) {
1559 			txsd->m = NULL;
1560 			m_copydata(m0, 0, mlen, (caddr_t)&txd->flit[2]);
1561 			flits = (mlen + 7) / 8 + 2;
1562 
1563 			wr_hi = htonl(V_WR_BCNTLFLT(mlen & 7) |
1564 			    V_WR_OP(FW_WROPCODE_TUNNEL_TX_PKT) |
1565 					  F_WR_SOP | F_WR_EOP | txqs.compl);
1566 			wr_lo = htonl(V_WR_LEN(flits) |
1567 			    V_WR_GEN(txqs.gen) | V_WR_TID(txq->token));
1568 			set_wr_hdr(&cpl->wr, wr_hi, wr_lo);
1569 			wmb();
1570 			ETHER_BPF_MTAP(pi->ifp, m0);
1571 			wr_gen2(txd, txqs.gen);
1572 			check_ring_tx_db(sc, txq, 0);
1573 			m_freem(m0);
1574 			return (0);
1575 		}
1576 		flits = 2;
1577 	}
1578 	wrp = (struct work_request_hdr *)txd;
1579 	sgp = (ndesc == 1) ? (struct sg_ent *)&txd->flit[flits] : sgl;
1580 	make_sgl(sgp, segs, nsegs);
1581 
1582 	sgl_flits = sgl_len(nsegs);
1583 
1584 	ETHER_BPF_MTAP(pi->ifp, m0);
1585 
1586 	KASSERT(ndesc <= 4, ("ndesc too large %d", ndesc));
1587 	wr_hi = htonl(V_WR_OP(FW_WROPCODE_TUNNEL_TX_PKT) | txqs.compl);
1588 	wr_lo = htonl(V_WR_TID(txq->token));
1589 	write_wr_hdr_sgl(ndesc, txd, &txqs, txq, sgl, flits,
1590 	    sgl_flits, wr_hi, wr_lo);
1591 	check_ring_tx_db(sc, txq, 0);
1592 
1593 	return (0);
1594 }
1595 
1596 #ifdef DEBUGNET
1597 int
1598 cxgb_debugnet_encap(struct sge_qset *qs, struct mbuf **m)
1599 {
1600 	int error;
1601 
1602 	error = t3_encap(qs, m);
1603 	if (error == 0)
1604 		check_ring_tx_db(qs->port->adapter, &qs->txq[TXQ_ETH], 1);
1605 	else if (*m != NULL) {
1606 		m_freem(*m);
1607 		*m = NULL;
1608 	}
1609 	return (error);
1610 }
1611 #endif
1612 
1613 void
1614 cxgb_tx_watchdog(void *arg)
1615 {
1616 	struct sge_qset *qs = arg;
1617 	struct sge_txq *txq = &qs->txq[TXQ_ETH];
1618 
1619         if (qs->coalescing != 0 &&
1620 	    (txq->in_use <= cxgb_tx_coalesce_enable_stop) &&
1621 	    TXQ_RING_EMPTY(qs))
1622                 qs->coalescing = 0;
1623         else if (qs->coalescing == 0 &&
1624 	    (txq->in_use >= cxgb_tx_coalesce_enable_start))
1625                 qs->coalescing = 1;
1626 	if (TXQ_TRYLOCK(qs)) {
1627 		qs->qs_flags |= QS_FLUSHING;
1628 		cxgb_start_locked(qs);
1629 		qs->qs_flags &= ~QS_FLUSHING;
1630 		TXQ_UNLOCK(qs);
1631 	}
1632 	if (qs->port->ifp->if_drv_flags & IFF_DRV_RUNNING)
1633 		callout_reset_on(&txq->txq_watchdog, hz/4, cxgb_tx_watchdog,
1634 		    qs, txq->txq_watchdog.c_cpu);
1635 }
1636 
1637 static void
1638 cxgb_tx_timeout(void *arg)
1639 {
1640 	struct sge_qset *qs = arg;
1641 	struct sge_txq *txq = &qs->txq[TXQ_ETH];
1642 
1643 	if (qs->coalescing == 0 && (txq->in_use >= (txq->size>>3)))
1644                 qs->coalescing = 1;
1645 	if (TXQ_TRYLOCK(qs)) {
1646 		qs->qs_flags |= QS_TIMEOUT;
1647 		cxgb_start_locked(qs);
1648 		qs->qs_flags &= ~QS_TIMEOUT;
1649 		TXQ_UNLOCK(qs);
1650 	}
1651 }
1652 
1653 static void
1654 cxgb_start_locked(struct sge_qset *qs)
1655 {
1656 	struct mbuf *m_head = NULL;
1657 	struct sge_txq *txq = &qs->txq[TXQ_ETH];
1658 	struct port_info *pi = qs->port;
1659 	struct ifnet *ifp = pi->ifp;
1660 
1661 	if (qs->qs_flags & (QS_FLUSHING|QS_TIMEOUT))
1662 		reclaim_completed_tx(qs, 0, TXQ_ETH);
1663 
1664 	if (!pi->link_config.link_ok) {
1665 		TXQ_RING_FLUSH(qs);
1666 		return;
1667 	}
1668 	TXQ_LOCK_ASSERT(qs);
1669 	while (!TXQ_RING_EMPTY(qs) && (ifp->if_drv_flags & IFF_DRV_RUNNING) &&
1670 	    pi->link_config.link_ok) {
1671 		reclaim_completed_tx(qs, cxgb_tx_reclaim_threshold, TXQ_ETH);
1672 
1673 		if (txq->size - txq->in_use <= TX_MAX_DESC)
1674 			break;
1675 
1676 		if ((m_head = cxgb_dequeue(qs)) == NULL)
1677 			break;
1678 		/*
1679 		 *  Encapsulation can modify our pointer, and or make it
1680 		 *  NULL on failure.  In that event, we can't requeue.
1681 		 */
1682 		if (t3_encap(qs, &m_head) || m_head == NULL)
1683 			break;
1684 
1685 		m_head = NULL;
1686 	}
1687 
1688 	if (txq->db_pending)
1689 		check_ring_tx_db(pi->adapter, txq, 1);
1690 
1691 	if (!TXQ_RING_EMPTY(qs) && callout_pending(&txq->txq_timer) == 0 &&
1692 	    pi->link_config.link_ok)
1693 		callout_reset_on(&txq->txq_timer, 1, cxgb_tx_timeout,
1694 		    qs, txq->txq_timer.c_cpu);
1695 	if (m_head != NULL)
1696 		m_freem(m_head);
1697 }
1698 
1699 static int
1700 cxgb_transmit_locked(struct ifnet *ifp, struct sge_qset *qs, struct mbuf *m)
1701 {
1702 	struct port_info *pi = qs->port;
1703 	struct sge_txq *txq = &qs->txq[TXQ_ETH];
1704 	struct buf_ring *br = txq->txq_mr;
1705 	int error, avail;
1706 
1707 	avail = txq->size - txq->in_use;
1708 	TXQ_LOCK_ASSERT(qs);
1709 
1710 	/*
1711 	 * We can only do a direct transmit if the following are true:
1712 	 * - we aren't coalescing (ring < 3/4 full)
1713 	 * - the link is up -- checked in caller
1714 	 * - there are no packets enqueued already
1715 	 * - there is space in hardware transmit queue
1716 	 */
1717 	if (check_pkt_coalesce(qs) == 0 &&
1718 	    !TXQ_RING_NEEDS_ENQUEUE(qs) && avail > TX_MAX_DESC) {
1719 		if (t3_encap(qs, &m)) {
1720 			if (m != NULL &&
1721 			    (error = drbr_enqueue(ifp, br, m)) != 0)
1722 				return (error);
1723 		} else {
1724 			if (txq->db_pending)
1725 				check_ring_tx_db(pi->adapter, txq, 1);
1726 
1727 			/*
1728 			 * We've bypassed the buf ring so we need to update
1729 			 * the stats directly
1730 			 */
1731 			txq->txq_direct_packets++;
1732 			txq->txq_direct_bytes += m->m_pkthdr.len;
1733 		}
1734 	} else if ((error = drbr_enqueue(ifp, br, m)) != 0)
1735 		return (error);
1736 
1737 	reclaim_completed_tx(qs, cxgb_tx_reclaim_threshold, TXQ_ETH);
1738 	if (!TXQ_RING_EMPTY(qs) && pi->link_config.link_ok &&
1739 	    (!check_pkt_coalesce(qs) || (drbr_inuse(ifp, br) >= 7)))
1740 		cxgb_start_locked(qs);
1741 	else if (!TXQ_RING_EMPTY(qs) && !callout_pending(&txq->txq_timer))
1742 		callout_reset_on(&txq->txq_timer, 1, cxgb_tx_timeout,
1743 		    qs, txq->txq_timer.c_cpu);
1744 	return (0);
1745 }
1746 
1747 int
1748 cxgb_transmit(struct ifnet *ifp, struct mbuf *m)
1749 {
1750 	struct sge_qset *qs;
1751 	struct port_info *pi = ifp->if_softc;
1752 	int error, qidx = pi->first_qset;
1753 
1754 	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0
1755 	    ||(!pi->link_config.link_ok)) {
1756 		m_freem(m);
1757 		return (0);
1758 	}
1759 
1760 	/* check if flowid is set */
1761 	if (M_HASHTYPE_GET(m) != M_HASHTYPE_NONE)
1762 		qidx = (m->m_pkthdr.flowid % pi->nqsets) + pi->first_qset;
1763 
1764 	qs = &pi->adapter->sge.qs[qidx];
1765 
1766 	if (TXQ_TRYLOCK(qs)) {
1767 		/* XXX running */
1768 		error = cxgb_transmit_locked(ifp, qs, m);
1769 		TXQ_UNLOCK(qs);
1770 	} else
1771 		error = drbr_enqueue(ifp, qs->txq[TXQ_ETH].txq_mr, m);
1772 	return (error);
1773 }
1774 
1775 void
1776 cxgb_qflush(struct ifnet *ifp)
1777 {
1778 	/*
1779 	 * flush any enqueued mbufs in the buf_rings
1780 	 * and in the transmit queues
1781 	 * no-op for now
1782 	 */
1783 	return;
1784 }
1785 
1786 /**
1787  *	write_imm - write a packet into a Tx descriptor as immediate data
1788  *	@d: the Tx descriptor to write
1789  *	@m: the packet
1790  *	@len: the length of packet data to write as immediate data
1791  *	@gen: the generation bit value to write
1792  *
1793  *	Writes a packet as immediate data into a Tx descriptor.  The packet
1794  *	contains a work request at its beginning.  We must write the packet
1795  *	carefully so the SGE doesn't read accidentally before it's written in
1796  *	its entirety.
1797  */
1798 static __inline void
1799 write_imm(struct tx_desc *d, caddr_t src,
1800 	  unsigned int len, unsigned int gen)
1801 {
1802 	struct work_request_hdr *from = (struct work_request_hdr *)src;
1803 	struct work_request_hdr *to = (struct work_request_hdr *)d;
1804 	uint32_t wr_hi, wr_lo;
1805 
1806 	KASSERT(len <= WR_LEN && len >= sizeof(*from),
1807 	    ("%s: invalid len %d", __func__, len));
1808 
1809 	memcpy(&to[1], &from[1], len - sizeof(*from));
1810 	wr_hi = from->wrh_hi | htonl(F_WR_SOP | F_WR_EOP |
1811 	    V_WR_BCNTLFLT(len & 7));
1812 	wr_lo = from->wrh_lo | htonl(V_WR_GEN(gen) | V_WR_LEN((len + 7) / 8));
1813 	set_wr_hdr(to, wr_hi, wr_lo);
1814 	wmb();
1815 	wr_gen2(d, gen);
1816 }
1817 
1818 /**
1819  *	check_desc_avail - check descriptor availability on a send queue
1820  *	@adap: the adapter
1821  *	@q: the TX queue
1822  *	@m: the packet needing the descriptors
1823  *	@ndesc: the number of Tx descriptors needed
1824  *	@qid: the Tx queue number in its queue set (TXQ_OFLD or TXQ_CTRL)
1825  *
1826  *	Checks if the requested number of Tx descriptors is available on an
1827  *	SGE send queue.  If the queue is already suspended or not enough
1828  *	descriptors are available the packet is queued for later transmission.
1829  *	Must be called with the Tx queue locked.
1830  *
1831  *	Returns 0 if enough descriptors are available, 1 if there aren't
1832  *	enough descriptors and the packet has been queued, and 2 if the caller
1833  *	needs to retry because there weren't enough descriptors at the
1834  *	beginning of the call but some freed up in the mean time.
1835  */
1836 static __inline int
1837 check_desc_avail(adapter_t *adap, struct sge_txq *q,
1838 		 struct mbuf *m, unsigned int ndesc,
1839 		 unsigned int qid)
1840 {
1841 	/*
1842 	 * XXX We currently only use this for checking the control queue
1843 	 * the control queue is only used for binding qsets which happens
1844 	 * at init time so we are guaranteed enough descriptors
1845 	 */
1846 	if (__predict_false(mbufq_len(&q->sendq))) {
1847 addq_exit:	(void )mbufq_enqueue(&q->sendq, m);
1848 		return 1;
1849 	}
1850 	if (__predict_false(q->size - q->in_use < ndesc)) {
1851 
1852 		struct sge_qset *qs = txq_to_qset(q, qid);
1853 
1854 		setbit(&qs->txq_stopped, qid);
1855 		if (should_restart_tx(q) &&
1856 		    test_and_clear_bit(qid, &qs->txq_stopped))
1857 			return 2;
1858 
1859 		q->stops++;
1860 		goto addq_exit;
1861 	}
1862 	return 0;
1863 }
1864 
1865 
1866 /**
1867  *	reclaim_completed_tx_imm - reclaim completed control-queue Tx descs
1868  *	@q: the SGE control Tx queue
1869  *
1870  *	This is a variant of reclaim_completed_tx() that is used for Tx queues
1871  *	that send only immediate data (presently just the control queues) and
1872  *	thus do not have any mbufs
1873  */
1874 static __inline void
1875 reclaim_completed_tx_imm(struct sge_txq *q)
1876 {
1877 	unsigned int reclaim = q->processed - q->cleaned;
1878 
1879 	q->in_use -= reclaim;
1880 	q->cleaned += reclaim;
1881 }
1882 
1883 /**
1884  *	ctrl_xmit - send a packet through an SGE control Tx queue
1885  *	@adap: the adapter
1886  *	@q: the control queue
1887  *	@m: the packet
1888  *
1889  *	Send a packet through an SGE control Tx queue.  Packets sent through
1890  *	a control queue must fit entirely as immediate data in a single Tx
1891  *	descriptor and have no page fragments.
1892  */
1893 static int
1894 ctrl_xmit(adapter_t *adap, struct sge_qset *qs, struct mbuf *m)
1895 {
1896 	int ret;
1897 	struct work_request_hdr *wrp = mtod(m, struct work_request_hdr *);
1898 	struct sge_txq *q = &qs->txq[TXQ_CTRL];
1899 
1900 	KASSERT(m->m_len <= WR_LEN, ("%s: bad tx data", __func__));
1901 
1902 	wrp->wrh_hi |= htonl(F_WR_SOP | F_WR_EOP);
1903 	wrp->wrh_lo = htonl(V_WR_TID(q->token));
1904 
1905 	TXQ_LOCK(qs);
1906 again:	reclaim_completed_tx_imm(q);
1907 
1908 	ret = check_desc_avail(adap, q, m, 1, TXQ_CTRL);
1909 	if (__predict_false(ret)) {
1910 		if (ret == 1) {
1911 			TXQ_UNLOCK(qs);
1912 			return (ENOSPC);
1913 		}
1914 		goto again;
1915 	}
1916 	write_imm(&q->desc[q->pidx], m->m_data, m->m_len, q->gen);
1917 
1918 	q->in_use++;
1919 	if (++q->pidx >= q->size) {
1920 		q->pidx = 0;
1921 		q->gen ^= 1;
1922 	}
1923 	TXQ_UNLOCK(qs);
1924 	wmb();
1925 	t3_write_reg(adap, A_SG_KDOORBELL,
1926 	    F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id));
1927 
1928 	m_free(m);
1929 	return (0);
1930 }
1931 
1932 
1933 /**
1934  *	restart_ctrlq - restart a suspended control queue
1935  *	@qs: the queue set cotaining the control queue
1936  *
1937  *	Resumes transmission on a suspended Tx control queue.
1938  */
1939 static void
1940 restart_ctrlq(void *data, int npending)
1941 {
1942 	struct mbuf *m;
1943 	struct sge_qset *qs = (struct sge_qset *)data;
1944 	struct sge_txq *q = &qs->txq[TXQ_CTRL];
1945 	adapter_t *adap = qs->port->adapter;
1946 
1947 	TXQ_LOCK(qs);
1948 again:	reclaim_completed_tx_imm(q);
1949 
1950 	while (q->in_use < q->size &&
1951 	       (m = mbufq_dequeue(&q->sendq)) != NULL) {
1952 
1953 		write_imm(&q->desc[q->pidx], m->m_data, m->m_len, q->gen);
1954 		m_free(m);
1955 
1956 		if (++q->pidx >= q->size) {
1957 			q->pidx = 0;
1958 			q->gen ^= 1;
1959 		}
1960 		q->in_use++;
1961 	}
1962 	if (mbufq_len(&q->sendq)) {
1963 		setbit(&qs->txq_stopped, TXQ_CTRL);
1964 
1965 		if (should_restart_tx(q) &&
1966 		    test_and_clear_bit(TXQ_CTRL, &qs->txq_stopped))
1967 			goto again;
1968 		q->stops++;
1969 	}
1970 	TXQ_UNLOCK(qs);
1971 	t3_write_reg(adap, A_SG_KDOORBELL,
1972 		     F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id));
1973 }
1974 
1975 
1976 /*
1977  * Send a management message through control queue 0
1978  */
1979 int
1980 t3_mgmt_tx(struct adapter *adap, struct mbuf *m)
1981 {
1982 	return ctrl_xmit(adap, &adap->sge.qs[0], m);
1983 }
1984 
1985 /**
1986  *	free_qset - free the resources of an SGE queue set
1987  *	@sc: the controller owning the queue set
1988  *	@q: the queue set
1989  *
1990  *	Release the HW and SW resources associated with an SGE queue set, such
1991  *	as HW contexts, packet buffers, and descriptor rings.  Traffic to the
1992  *	queue set must be quiesced prior to calling this.
1993  */
1994 static void
1995 t3_free_qset(adapter_t *sc, struct sge_qset *q)
1996 {
1997 	int i;
1998 
1999 	reclaim_completed_tx(q, 0, TXQ_ETH);
2000 	if (q->txq[TXQ_ETH].txq_mr != NULL)
2001 		buf_ring_free(q->txq[TXQ_ETH].txq_mr, M_DEVBUF);
2002 	if (q->txq[TXQ_ETH].txq_ifq != NULL) {
2003 		ifq_delete(q->txq[TXQ_ETH].txq_ifq);
2004 		free(q->txq[TXQ_ETH].txq_ifq, M_DEVBUF);
2005 	}
2006 
2007 	for (i = 0; i < SGE_RXQ_PER_SET; ++i) {
2008 		if (q->fl[i].desc) {
2009 			mtx_lock_spin(&sc->sge.reg_lock);
2010 			t3_sge_disable_fl(sc, q->fl[i].cntxt_id);
2011 			mtx_unlock_spin(&sc->sge.reg_lock);
2012 			bus_dmamap_unload(q->fl[i].desc_tag, q->fl[i].desc_map);
2013 			bus_dmamem_free(q->fl[i].desc_tag, q->fl[i].desc,
2014 					q->fl[i].desc_map);
2015 			bus_dma_tag_destroy(q->fl[i].desc_tag);
2016 			bus_dma_tag_destroy(q->fl[i].entry_tag);
2017 		}
2018 		if (q->fl[i].sdesc) {
2019 			free_rx_bufs(sc, &q->fl[i]);
2020 			free(q->fl[i].sdesc, M_DEVBUF);
2021 		}
2022 	}
2023 
2024 	mtx_unlock(&q->lock);
2025 	MTX_DESTROY(&q->lock);
2026 	for (i = 0; i < SGE_TXQ_PER_SET; i++) {
2027 		if (q->txq[i].desc) {
2028 			mtx_lock_spin(&sc->sge.reg_lock);
2029 			t3_sge_enable_ecntxt(sc, q->txq[i].cntxt_id, 0);
2030 			mtx_unlock_spin(&sc->sge.reg_lock);
2031 			bus_dmamap_unload(q->txq[i].desc_tag,
2032 					q->txq[i].desc_map);
2033 			bus_dmamem_free(q->txq[i].desc_tag, q->txq[i].desc,
2034 					q->txq[i].desc_map);
2035 			bus_dma_tag_destroy(q->txq[i].desc_tag);
2036 			bus_dma_tag_destroy(q->txq[i].entry_tag);
2037 		}
2038 		if (q->txq[i].sdesc) {
2039 			free(q->txq[i].sdesc, M_DEVBUF);
2040 		}
2041 	}
2042 
2043 	if (q->rspq.desc) {
2044 		mtx_lock_spin(&sc->sge.reg_lock);
2045 		t3_sge_disable_rspcntxt(sc, q->rspq.cntxt_id);
2046 		mtx_unlock_spin(&sc->sge.reg_lock);
2047 
2048 		bus_dmamap_unload(q->rspq.desc_tag, q->rspq.desc_map);
2049 		bus_dmamem_free(q->rspq.desc_tag, q->rspq.desc,
2050 			        q->rspq.desc_map);
2051 		bus_dma_tag_destroy(q->rspq.desc_tag);
2052 		MTX_DESTROY(&q->rspq.lock);
2053 	}
2054 
2055 #if defined(INET6) || defined(INET)
2056 	tcp_lro_free(&q->lro.ctrl);
2057 #endif
2058 
2059 	bzero(q, sizeof(*q));
2060 }
2061 
2062 /**
2063  *	t3_free_sge_resources - free SGE resources
2064  *	@sc: the adapter softc
2065  *
2066  *	Frees resources used by the SGE queue sets.
2067  */
2068 void
2069 t3_free_sge_resources(adapter_t *sc, int nqsets)
2070 {
2071 	int i;
2072 
2073 	for (i = 0; i < nqsets; ++i) {
2074 		TXQ_LOCK(&sc->sge.qs[i]);
2075 		t3_free_qset(sc, &sc->sge.qs[i]);
2076 	}
2077 }
2078 
2079 /**
2080  *	t3_sge_start - enable SGE
2081  *	@sc: the controller softc
2082  *
2083  *	Enables the SGE for DMAs.  This is the last step in starting packet
2084  *	transfers.
2085  */
2086 void
2087 t3_sge_start(adapter_t *sc)
2088 {
2089 	t3_set_reg_field(sc, A_SG_CONTROL, F_GLOBALENABLE, F_GLOBALENABLE);
2090 }
2091 
2092 /**
2093  *	t3_sge_stop - disable SGE operation
2094  *	@sc: the adapter
2095  *
2096  *	Disables the DMA engine.  This can be called in emeregencies (e.g.,
2097  *	from error interrupts) or from normal process context.  In the latter
2098  *	case it also disables any pending queue restart tasklets.  Note that
2099  *	if it is called in interrupt context it cannot disable the restart
2100  *	tasklets as it cannot wait, however the tasklets will have no effect
2101  *	since the doorbells are disabled and the driver will call this again
2102  *	later from process context, at which time the tasklets will be stopped
2103  *	if they are still running.
2104  */
2105 void
2106 t3_sge_stop(adapter_t *sc)
2107 {
2108 
2109 	t3_set_reg_field(sc, A_SG_CONTROL, F_GLOBALENABLE, 0);
2110 }
2111 
2112 /**
2113  *	t3_free_tx_desc - reclaims Tx descriptors and their buffers
2114  *	@adapter: the adapter
2115  *	@q: the Tx queue to reclaim descriptors from
2116  *	@reclaimable: the number of descriptors to reclaim
2117  *      @m_vec_size: maximum number of buffers to reclaim
2118  *      @desc_reclaimed: returns the number of descriptors reclaimed
2119  *
2120  *	Reclaims Tx descriptors from an SGE Tx queue and frees the associated
2121  *	Tx buffers.  Called with the Tx queue lock held.
2122  *
2123  *      Returns number of buffers of reclaimed
2124  */
2125 void
2126 t3_free_tx_desc(struct sge_qset *qs, int reclaimable, int queue)
2127 {
2128 	struct tx_sw_desc *txsd;
2129 	unsigned int cidx, mask;
2130 	struct sge_txq *q = &qs->txq[queue];
2131 
2132 #ifdef T3_TRACE
2133 	T3_TRACE2(sc->tb[q->cntxt_id & 7],
2134 		  "reclaiming %u Tx descriptors at cidx %u", reclaimable, cidx);
2135 #endif
2136 	cidx = q->cidx;
2137 	mask = q->size - 1;
2138 	txsd = &q->sdesc[cidx];
2139 
2140 	mtx_assert(&qs->lock, MA_OWNED);
2141 	while (reclaimable--) {
2142 		prefetch(q->sdesc[(cidx + 1) & mask].m);
2143 		prefetch(q->sdesc[(cidx + 2) & mask].m);
2144 
2145 		if (txsd->m != NULL) {
2146 			if (txsd->flags & TX_SW_DESC_MAPPED) {
2147 				bus_dmamap_unload(q->entry_tag, txsd->map);
2148 				txsd->flags &= ~TX_SW_DESC_MAPPED;
2149 			}
2150 			m_freem_list(txsd->m);
2151 			txsd->m = NULL;
2152 		} else
2153 			q->txq_skipped++;
2154 
2155 		++txsd;
2156 		if (++cidx == q->size) {
2157 			cidx = 0;
2158 			txsd = q->sdesc;
2159 		}
2160 	}
2161 	q->cidx = cidx;
2162 
2163 }
2164 
2165 /**
2166  *	is_new_response - check if a response is newly written
2167  *	@r: the response descriptor
2168  *	@q: the response queue
2169  *
2170  *	Returns true if a response descriptor contains a yet unprocessed
2171  *	response.
2172  */
2173 static __inline int
2174 is_new_response(const struct rsp_desc *r,
2175     const struct sge_rspq *q)
2176 {
2177 	return (r->intr_gen & F_RSPD_GEN2) == q->gen;
2178 }
2179 
2180 #define RSPD_GTS_MASK  (F_RSPD_TXQ0_GTS | F_RSPD_TXQ1_GTS)
2181 #define RSPD_CTRL_MASK (RSPD_GTS_MASK | \
2182 			V_RSPD_TXQ0_CR(M_RSPD_TXQ0_CR) | \
2183 			V_RSPD_TXQ1_CR(M_RSPD_TXQ1_CR) | \
2184 			V_RSPD_TXQ2_CR(M_RSPD_TXQ2_CR))
2185 
2186 /* How long to delay the next interrupt in case of memory shortage, in 0.1us. */
2187 #define NOMEM_INTR_DELAY 2500
2188 
2189 #ifdef TCP_OFFLOAD
2190 /**
2191  *	write_ofld_wr - write an offload work request
2192  *	@adap: the adapter
2193  *	@m: the packet to send
2194  *	@q: the Tx queue
2195  *	@pidx: index of the first Tx descriptor to write
2196  *	@gen: the generation value to use
2197  *	@ndesc: number of descriptors the packet will occupy
2198  *
2199  *	Write an offload work request to send the supplied packet.  The packet
2200  *	data already carry the work request with most fields populated.
2201  */
2202 static void
2203 write_ofld_wr(adapter_t *adap, struct mbuf *m, struct sge_txq *q,
2204     unsigned int pidx, unsigned int gen, unsigned int ndesc)
2205 {
2206 	unsigned int sgl_flits, flits;
2207 	int i, idx, nsegs, wrlen;
2208 	struct work_request_hdr *from;
2209 	struct sg_ent *sgp, t3sgl[TX_MAX_SEGS / 2 + 1];
2210 	struct tx_desc *d = &q->desc[pidx];
2211 	struct txq_state txqs;
2212 	struct sglist_seg *segs;
2213 	struct ofld_hdr *oh = mtod(m, struct ofld_hdr *);
2214 	struct sglist *sgl;
2215 
2216 	from = (void *)(oh + 1);	/* Start of WR within mbuf */
2217 	wrlen = m->m_len - sizeof(*oh);
2218 
2219 	if (!(oh->flags & F_HDR_SGL)) {
2220 		write_imm(d, (caddr_t)from, wrlen, gen);
2221 
2222 		/*
2223 		 * mbuf with "real" immediate tx data will be enqueue_wr'd by
2224 		 * t3_push_frames and freed in wr_ack.  Others, like those sent
2225 		 * down by close_conn, t3_send_reset, etc. should be freed here.
2226 		 */
2227 		if (!(oh->flags & F_HDR_DF))
2228 			m_free(m);
2229 		return;
2230 	}
2231 
2232 	memcpy(&d->flit[1], &from[1], wrlen - sizeof(*from));
2233 
2234 	sgl = oh->sgl;
2235 	flits = wrlen / 8;
2236 	sgp = (ndesc == 1) ? (struct sg_ent *)&d->flit[flits] : t3sgl;
2237 
2238 	nsegs = sgl->sg_nseg;
2239 	segs = sgl->sg_segs;
2240 	for (idx = 0, i = 0; i < nsegs; i++) {
2241 		KASSERT(segs[i].ss_len, ("%s: 0 len in sgl", __func__));
2242 		if (i && idx == 0)
2243 			++sgp;
2244 		sgp->len[idx] = htobe32(segs[i].ss_len);
2245 		sgp->addr[idx] = htobe64(segs[i].ss_paddr);
2246 		idx ^= 1;
2247 	}
2248 	if (idx) {
2249 		sgp->len[idx] = 0;
2250 		sgp->addr[idx] = 0;
2251 	}
2252 
2253 	sgl_flits = sgl_len(nsegs);
2254 	txqs.gen = gen;
2255 	txqs.pidx = pidx;
2256 	txqs.compl = 0;
2257 
2258 	write_wr_hdr_sgl(ndesc, d, &txqs, q, t3sgl, flits, sgl_flits,
2259 	    from->wrh_hi, from->wrh_lo);
2260 }
2261 
2262 /**
2263  *	ofld_xmit - send a packet through an offload queue
2264  *	@adap: the adapter
2265  *	@q: the Tx offload queue
2266  *	@m: the packet
2267  *
2268  *	Send an offload packet through an SGE offload queue.
2269  */
2270 static int
2271 ofld_xmit(adapter_t *adap, struct sge_qset *qs, struct mbuf *m)
2272 {
2273 	int ret;
2274 	unsigned int ndesc;
2275 	unsigned int pidx, gen;
2276 	struct sge_txq *q = &qs->txq[TXQ_OFLD];
2277 	struct ofld_hdr *oh = mtod(m, struct ofld_hdr *);
2278 
2279 	ndesc = G_HDR_NDESC(oh->flags);
2280 
2281 	TXQ_LOCK(qs);
2282 again:	reclaim_completed_tx(qs, 16, TXQ_OFLD);
2283 	ret = check_desc_avail(adap, q, m, ndesc, TXQ_OFLD);
2284 	if (__predict_false(ret)) {
2285 		if (ret == 1) {
2286 			TXQ_UNLOCK(qs);
2287 			return (EINTR);
2288 		}
2289 		goto again;
2290 	}
2291 
2292 	gen = q->gen;
2293 	q->in_use += ndesc;
2294 	pidx = q->pidx;
2295 	q->pidx += ndesc;
2296 	if (q->pidx >= q->size) {
2297 		q->pidx -= q->size;
2298 		q->gen ^= 1;
2299 	}
2300 
2301 	write_ofld_wr(adap, m, q, pidx, gen, ndesc);
2302 	check_ring_tx_db(adap, q, 1);
2303 	TXQ_UNLOCK(qs);
2304 
2305 	return (0);
2306 }
2307 
2308 /**
2309  *	restart_offloadq - restart a suspended offload queue
2310  *	@qs: the queue set cotaining the offload queue
2311  *
2312  *	Resumes transmission on a suspended Tx offload queue.
2313  */
2314 static void
2315 restart_offloadq(void *data, int npending)
2316 {
2317 	struct mbuf *m;
2318 	struct sge_qset *qs = data;
2319 	struct sge_txq *q = &qs->txq[TXQ_OFLD];
2320 	adapter_t *adap = qs->port->adapter;
2321 
2322 	TXQ_LOCK(qs);
2323 again:
2324 	while ((m = mbufq_first(&q->sendq)) != NULL) {
2325 		unsigned int gen, pidx;
2326 		struct ofld_hdr *oh = mtod(m, struct ofld_hdr *);
2327 		unsigned int ndesc = G_HDR_NDESC(oh->flags);
2328 
2329 		if (__predict_false(q->size - q->in_use < ndesc)) {
2330 			setbit(&qs->txq_stopped, TXQ_OFLD);
2331 			if (should_restart_tx(q) &&
2332 			    test_and_clear_bit(TXQ_OFLD, &qs->txq_stopped))
2333 				goto again;
2334 			q->stops++;
2335 			break;
2336 		}
2337 
2338 		gen = q->gen;
2339 		q->in_use += ndesc;
2340 		pidx = q->pidx;
2341 		q->pidx += ndesc;
2342 		if (q->pidx >= q->size) {
2343 			q->pidx -= q->size;
2344 			q->gen ^= 1;
2345 		}
2346 
2347 		(void)mbufq_dequeue(&q->sendq);
2348 		TXQ_UNLOCK(qs);
2349 		write_ofld_wr(adap, m, q, pidx, gen, ndesc);
2350 		TXQ_LOCK(qs);
2351 	}
2352 #if USE_GTS
2353 	set_bit(TXQ_RUNNING, &q->flags);
2354 	set_bit(TXQ_LAST_PKT_DB, &q->flags);
2355 #endif
2356 	TXQ_UNLOCK(qs);
2357 	wmb();
2358 	t3_write_reg(adap, A_SG_KDOORBELL,
2359 		     F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id));
2360 }
2361 
2362 /**
2363  *	t3_offload_tx - send an offload packet
2364  *	@m: the packet
2365  *
2366  *	Sends an offload packet.  We use the packet priority to select the
2367  *	appropriate Tx queue as follows: bit 0 indicates whether the packet
2368  *	should be sent as regular or control, bits 1-3 select the queue set.
2369  */
2370 int
2371 t3_offload_tx(struct adapter *sc, struct mbuf *m)
2372 {
2373 	struct ofld_hdr *oh = mtod(m, struct ofld_hdr *);
2374 	struct sge_qset *qs = &sc->sge.qs[G_HDR_QSET(oh->flags)];
2375 
2376 	if (oh->flags & F_HDR_CTRL) {
2377 		m_adj(m, sizeof (*oh));	/* trim ofld_hdr off */
2378 		return (ctrl_xmit(sc, qs, m));
2379 	} else
2380 		return (ofld_xmit(sc, qs, m));
2381 }
2382 #endif
2383 
2384 static void
2385 restart_tx(struct sge_qset *qs)
2386 {
2387 	struct adapter *sc = qs->port->adapter;
2388 
2389 	if (isset(&qs->txq_stopped, TXQ_OFLD) &&
2390 	    should_restart_tx(&qs->txq[TXQ_OFLD]) &&
2391 	    test_and_clear_bit(TXQ_OFLD, &qs->txq_stopped)) {
2392 		qs->txq[TXQ_OFLD].restarts++;
2393 		taskqueue_enqueue(sc->tq, &qs->txq[TXQ_OFLD].qresume_task);
2394 	}
2395 
2396 	if (isset(&qs->txq_stopped, TXQ_CTRL) &&
2397 	    should_restart_tx(&qs->txq[TXQ_CTRL]) &&
2398 	    test_and_clear_bit(TXQ_CTRL, &qs->txq_stopped)) {
2399 		qs->txq[TXQ_CTRL].restarts++;
2400 		taskqueue_enqueue(sc->tq, &qs->txq[TXQ_CTRL].qresume_task);
2401 	}
2402 }
2403 
2404 /**
2405  *	t3_sge_alloc_qset - initialize an SGE queue set
2406  *	@sc: the controller softc
2407  *	@id: the queue set id
2408  *	@nports: how many Ethernet ports will be using this queue set
2409  *	@irq_vec_idx: the IRQ vector index for response queue interrupts
2410  *	@p: configuration parameters for this queue set
2411  *	@ntxq: number of Tx queues for the queue set
2412  *	@pi: port info for queue set
2413  *
2414  *	Allocate resources and initialize an SGE queue set.  A queue set
2415  *	comprises a response queue, two Rx free-buffer queues, and up to 3
2416  *	Tx queues.  The Tx queues are assigned roles in the order Ethernet
2417  *	queue, offload queue, and control queue.
2418  */
2419 int
2420 t3_sge_alloc_qset(adapter_t *sc, u_int id, int nports, int irq_vec_idx,
2421 		  const struct qset_params *p, int ntxq, struct port_info *pi)
2422 {
2423 	struct sge_qset *q = &sc->sge.qs[id];
2424 	int i, ret = 0;
2425 
2426 	MTX_INIT(&q->lock, q->namebuf, NULL, MTX_DEF);
2427 	q->port = pi;
2428 	q->adap = sc;
2429 
2430 	if ((q->txq[TXQ_ETH].txq_mr = buf_ring_alloc(cxgb_txq_buf_ring_size,
2431 	    M_DEVBUF, M_WAITOK, &q->lock)) == NULL) {
2432 		device_printf(sc->dev, "failed to allocate mbuf ring\n");
2433 		goto err;
2434 	}
2435 	if ((q->txq[TXQ_ETH].txq_ifq = malloc(sizeof(struct ifaltq), M_DEVBUF,
2436 	    M_NOWAIT | M_ZERO)) == NULL) {
2437 		device_printf(sc->dev, "failed to allocate ifq\n");
2438 		goto err;
2439 	}
2440 	ifq_init(q->txq[TXQ_ETH].txq_ifq, pi->ifp);
2441 	callout_init(&q->txq[TXQ_ETH].txq_timer, 1);
2442 	callout_init(&q->txq[TXQ_ETH].txq_watchdog, 1);
2443 	q->txq[TXQ_ETH].txq_timer.c_cpu = id % mp_ncpus;
2444 	q->txq[TXQ_ETH].txq_watchdog.c_cpu = id % mp_ncpus;
2445 
2446 	init_qset_cntxt(q, id);
2447 	q->idx = id;
2448 	if ((ret = alloc_ring(sc, p->fl_size, sizeof(struct rx_desc),
2449 		    sizeof(struct rx_sw_desc), &q->fl[0].phys_addr,
2450 		    &q->fl[0].desc, &q->fl[0].sdesc,
2451 		    &q->fl[0].desc_tag, &q->fl[0].desc_map,
2452 		    sc->rx_dmat, &q->fl[0].entry_tag)) != 0) {
2453 		printf("error %d from alloc ring fl0\n", ret);
2454 		goto err;
2455 	}
2456 
2457 	if ((ret = alloc_ring(sc, p->jumbo_size, sizeof(struct rx_desc),
2458 		    sizeof(struct rx_sw_desc), &q->fl[1].phys_addr,
2459 		    &q->fl[1].desc, &q->fl[1].sdesc,
2460 		    &q->fl[1].desc_tag, &q->fl[1].desc_map,
2461 		    sc->rx_jumbo_dmat, &q->fl[1].entry_tag)) != 0) {
2462 		printf("error %d from alloc ring fl1\n", ret);
2463 		goto err;
2464 	}
2465 
2466 	if ((ret = alloc_ring(sc, p->rspq_size, sizeof(struct rsp_desc), 0,
2467 		    &q->rspq.phys_addr, &q->rspq.desc, NULL,
2468 		    &q->rspq.desc_tag, &q->rspq.desc_map,
2469 		    NULL, NULL)) != 0) {
2470 		printf("error %d from alloc ring rspq\n", ret);
2471 		goto err;
2472 	}
2473 
2474 	snprintf(q->rspq.lockbuf, RSPQ_NAME_LEN, "t3 rspq lock %d:%d",
2475 	    device_get_unit(sc->dev), irq_vec_idx);
2476 	MTX_INIT(&q->rspq.lock, q->rspq.lockbuf, NULL, MTX_DEF);
2477 
2478 	for (i = 0; i < ntxq; ++i) {
2479 		size_t sz = i == TXQ_CTRL ? 0 : sizeof(struct tx_sw_desc);
2480 
2481 		if ((ret = alloc_ring(sc, p->txq_size[i],
2482 			    sizeof(struct tx_desc), sz,
2483 			    &q->txq[i].phys_addr, &q->txq[i].desc,
2484 			    &q->txq[i].sdesc, &q->txq[i].desc_tag,
2485 			    &q->txq[i].desc_map,
2486 			    sc->tx_dmat, &q->txq[i].entry_tag)) != 0) {
2487 			printf("error %d from alloc ring tx %i\n", ret, i);
2488 			goto err;
2489 		}
2490 		mbufq_init(&q->txq[i].sendq, INT_MAX);
2491 		q->txq[i].gen = 1;
2492 		q->txq[i].size = p->txq_size[i];
2493 	}
2494 
2495 #ifdef TCP_OFFLOAD
2496 	TASK_INIT(&q->txq[TXQ_OFLD].qresume_task, 0, restart_offloadq, q);
2497 #endif
2498 	TASK_INIT(&q->txq[TXQ_CTRL].qresume_task, 0, restart_ctrlq, q);
2499 	TASK_INIT(&q->txq[TXQ_ETH].qreclaim_task, 0, sge_txq_reclaim_handler, q);
2500 	TASK_INIT(&q->txq[TXQ_OFLD].qreclaim_task, 0, sge_txq_reclaim_handler, q);
2501 
2502 	q->fl[0].gen = q->fl[1].gen = 1;
2503 	q->fl[0].size = p->fl_size;
2504 	q->fl[1].size = p->jumbo_size;
2505 
2506 	q->rspq.gen = 1;
2507 	q->rspq.cidx = 0;
2508 	q->rspq.size = p->rspq_size;
2509 
2510 	q->txq[TXQ_ETH].stop_thres = nports *
2511 	    flits_to_desc(sgl_len(TX_MAX_SEGS + 1) + 3);
2512 
2513 	q->fl[0].buf_size = MCLBYTES;
2514 	q->fl[0].zone = zone_pack;
2515 	q->fl[0].type = EXT_PACKET;
2516 
2517 	if (p->jumbo_buf_size ==  MJUM16BYTES) {
2518 		q->fl[1].zone = zone_jumbo16;
2519 		q->fl[1].type = EXT_JUMBO16;
2520 	} else if (p->jumbo_buf_size ==  MJUM9BYTES) {
2521 		q->fl[1].zone = zone_jumbo9;
2522 		q->fl[1].type = EXT_JUMBO9;
2523 	} else if (p->jumbo_buf_size ==  MJUMPAGESIZE) {
2524 		q->fl[1].zone = zone_jumbop;
2525 		q->fl[1].type = EXT_JUMBOP;
2526 	} else {
2527 		KASSERT(0, ("can't deal with jumbo_buf_size %d.", p->jumbo_buf_size));
2528 		ret = EDOOFUS;
2529 		goto err;
2530 	}
2531 	q->fl[1].buf_size = p->jumbo_buf_size;
2532 
2533 	/* Allocate and setup the lro_ctrl structure */
2534 	q->lro.enabled = !!(pi->ifp->if_capenable & IFCAP_LRO);
2535 #if defined(INET6) || defined(INET)
2536 	ret = tcp_lro_init(&q->lro.ctrl);
2537 	if (ret) {
2538 		printf("error %d from tcp_lro_init\n", ret);
2539 		goto err;
2540 	}
2541 #endif
2542 	q->lro.ctrl.ifp = pi->ifp;
2543 
2544 	mtx_lock_spin(&sc->sge.reg_lock);
2545 	ret = -t3_sge_init_rspcntxt(sc, q->rspq.cntxt_id, irq_vec_idx,
2546 				   q->rspq.phys_addr, q->rspq.size,
2547 				   q->fl[0].buf_size, 1, 0);
2548 	if (ret) {
2549 		printf("error %d from t3_sge_init_rspcntxt\n", ret);
2550 		goto err_unlock;
2551 	}
2552 
2553 	for (i = 0; i < SGE_RXQ_PER_SET; ++i) {
2554 		ret = -t3_sge_init_flcntxt(sc, q->fl[i].cntxt_id, 0,
2555 					  q->fl[i].phys_addr, q->fl[i].size,
2556 					  q->fl[i].buf_size, p->cong_thres, 1,
2557 					  0);
2558 		if (ret) {
2559 			printf("error %d from t3_sge_init_flcntxt for index i=%d\n", ret, i);
2560 			goto err_unlock;
2561 		}
2562 	}
2563 
2564 	ret = -t3_sge_init_ecntxt(sc, q->txq[TXQ_ETH].cntxt_id, USE_GTS,
2565 				 SGE_CNTXT_ETH, id, q->txq[TXQ_ETH].phys_addr,
2566 				 q->txq[TXQ_ETH].size, q->txq[TXQ_ETH].token,
2567 				 1, 0);
2568 	if (ret) {
2569 		printf("error %d from t3_sge_init_ecntxt\n", ret);
2570 		goto err_unlock;
2571 	}
2572 
2573 	if (ntxq > 1) {
2574 		ret = -t3_sge_init_ecntxt(sc, q->txq[TXQ_OFLD].cntxt_id,
2575 					 USE_GTS, SGE_CNTXT_OFLD, id,
2576 					 q->txq[TXQ_OFLD].phys_addr,
2577 					 q->txq[TXQ_OFLD].size, 0, 1, 0);
2578 		if (ret) {
2579 			printf("error %d from t3_sge_init_ecntxt\n", ret);
2580 			goto err_unlock;
2581 		}
2582 	}
2583 
2584 	if (ntxq > 2) {
2585 		ret = -t3_sge_init_ecntxt(sc, q->txq[TXQ_CTRL].cntxt_id, 0,
2586 					 SGE_CNTXT_CTRL, id,
2587 					 q->txq[TXQ_CTRL].phys_addr,
2588 					 q->txq[TXQ_CTRL].size,
2589 					 q->txq[TXQ_CTRL].token, 1, 0);
2590 		if (ret) {
2591 			printf("error %d from t3_sge_init_ecntxt\n", ret);
2592 			goto err_unlock;
2593 		}
2594 	}
2595 
2596 	mtx_unlock_spin(&sc->sge.reg_lock);
2597 	t3_update_qset_coalesce(q, p);
2598 
2599 	refill_fl(sc, &q->fl[0], q->fl[0].size);
2600 	refill_fl(sc, &q->fl[1], q->fl[1].size);
2601 	refill_rspq(sc, &q->rspq, q->rspq.size - 1);
2602 
2603 	t3_write_reg(sc, A_SG_GTS, V_RSPQ(q->rspq.cntxt_id) |
2604 		     V_NEWTIMER(q->rspq.holdoff_tmr));
2605 
2606 	return (0);
2607 
2608 err_unlock:
2609 	mtx_unlock_spin(&sc->sge.reg_lock);
2610 err:
2611 	TXQ_LOCK(q);
2612 	t3_free_qset(sc, q);
2613 
2614 	return (ret);
2615 }
2616 
2617 /*
2618  * Remove CPL_RX_PKT headers from the mbuf and reduce it to a regular mbuf with
2619  * ethernet data.  Hardware assistance with various checksums and any vlan tag
2620  * will also be taken into account here.
2621  */
2622 void
2623 t3_rx_eth(struct adapter *adap, struct mbuf *m, int ethpad)
2624 {
2625 	struct cpl_rx_pkt *cpl = (struct cpl_rx_pkt *)(mtod(m, uint8_t *) + ethpad);
2626 	struct port_info *pi = &adap->port[adap->rxpkt_map[cpl->iff]];
2627 	struct ifnet *ifp = pi->ifp;
2628 
2629 	if (cpl->vlan_valid) {
2630 		m->m_pkthdr.ether_vtag = ntohs(cpl->vlan);
2631 		m->m_flags |= M_VLANTAG;
2632 	}
2633 
2634 	m->m_pkthdr.rcvif = ifp;
2635 	/*
2636 	 * adjust after conversion to mbuf chain
2637 	 */
2638 	m->m_pkthdr.len -= (sizeof(*cpl) + ethpad);
2639 	m->m_len -= (sizeof(*cpl) + ethpad);
2640 	m->m_data += (sizeof(*cpl) + ethpad);
2641 
2642 	if (!cpl->fragment && cpl->csum_valid && cpl->csum == 0xffff) {
2643 		struct ether_header *eh = mtod(m, void *);
2644 		uint16_t eh_type;
2645 
2646 		if (eh->ether_type == htons(ETHERTYPE_VLAN)) {
2647 			struct ether_vlan_header *evh = mtod(m, void *);
2648 
2649 			eh_type = evh->evl_proto;
2650 		} else
2651 			eh_type = eh->ether_type;
2652 
2653 		if (ifp->if_capenable & IFCAP_RXCSUM &&
2654 		    eh_type == htons(ETHERTYPE_IP)) {
2655 			m->m_pkthdr.csum_flags = (CSUM_IP_CHECKED |
2656 			    CSUM_IP_VALID | CSUM_DATA_VALID | CSUM_PSEUDO_HDR);
2657 			m->m_pkthdr.csum_data = 0xffff;
2658 		} else if (ifp->if_capenable & IFCAP_RXCSUM_IPV6 &&
2659 		    eh_type == htons(ETHERTYPE_IPV6)) {
2660 			m->m_pkthdr.csum_flags = (CSUM_DATA_VALID_IPV6 |
2661 			    CSUM_PSEUDO_HDR);
2662 			m->m_pkthdr.csum_data = 0xffff;
2663 		}
2664 	}
2665 }
2666 
2667 /**
2668  *	get_packet - return the next ingress packet buffer from a free list
2669  *	@adap: the adapter that received the packet
2670  *	@drop_thres: # of remaining buffers before we start dropping packets
2671  *	@qs: the qset that the SGE free list holding the packet belongs to
2672  *      @mh: the mbuf header, contains a pointer to the head and tail of the mbuf chain
2673  *      @r: response descriptor
2674  *
2675  *	Get the next packet from a free list and complete setup of the
2676  *	sk_buff.  If the packet is small we make a copy and recycle the
2677  *	original buffer, otherwise we use the original buffer itself.  If a
2678  *	positive drop threshold is supplied packets are dropped and their
2679  *	buffers recycled if (a) the number of remaining buffers is under the
2680  *	threshold and the packet is too big to copy, or (b) the packet should
2681  *	be copied but there is no memory for the copy.
2682  */
2683 static int
2684 get_packet(adapter_t *adap, unsigned int drop_thres, struct sge_qset *qs,
2685     struct t3_mbuf_hdr *mh, struct rsp_desc *r)
2686 {
2687 
2688 	unsigned int len_cq =  ntohl(r->len_cq);
2689 	struct sge_fl *fl = (len_cq & F_RSPD_FLQ) ? &qs->fl[1] : &qs->fl[0];
2690 	int mask, cidx = fl->cidx;
2691 	struct rx_sw_desc *sd = &fl->sdesc[cidx];
2692 	uint32_t len = G_RSPD_LEN(len_cq);
2693 	uint32_t flags = M_EXT;
2694 	uint8_t sopeop = G_RSPD_SOP_EOP(ntohl(r->flags));
2695 	caddr_t cl;
2696 	struct mbuf *m;
2697 	int ret = 0;
2698 
2699 	mask = fl->size - 1;
2700 	prefetch(fl->sdesc[(cidx + 1) & mask].m);
2701 	prefetch(fl->sdesc[(cidx + 2) & mask].m);
2702 	prefetch(fl->sdesc[(cidx + 1) & mask].rxsd_cl);
2703 	prefetch(fl->sdesc[(cidx + 2) & mask].rxsd_cl);
2704 
2705 	fl->credits--;
2706 	bus_dmamap_sync(fl->entry_tag, sd->map, BUS_DMASYNC_POSTREAD);
2707 
2708 	if (recycle_enable && len <= SGE_RX_COPY_THRES &&
2709 	    sopeop == RSPQ_SOP_EOP) {
2710 		if ((m = m_gethdr(M_NOWAIT, MT_DATA)) == NULL)
2711 			goto skip_recycle;
2712 		cl = mtod(m, void *);
2713 		memcpy(cl, sd->rxsd_cl, len);
2714 		recycle_rx_buf(adap, fl, fl->cidx);
2715 		m->m_pkthdr.len = m->m_len = len;
2716 		m->m_flags = 0;
2717 		mh->mh_head = mh->mh_tail = m;
2718 		ret = 1;
2719 		goto done;
2720 	} else {
2721 	skip_recycle:
2722 		bus_dmamap_unload(fl->entry_tag, sd->map);
2723 		cl = sd->rxsd_cl;
2724 		m = sd->m;
2725 
2726 		if ((sopeop == RSPQ_SOP_EOP) ||
2727 		    (sopeop == RSPQ_SOP))
2728 			flags |= M_PKTHDR;
2729 		m_init(m, M_NOWAIT, MT_DATA, flags);
2730 		if (fl->zone == zone_pack) {
2731 			/*
2732 			 * restore clobbered data pointer
2733 			 */
2734 			m->m_data = m->m_ext.ext_buf;
2735 		} else {
2736 			m_cljset(m, cl, fl->type);
2737 		}
2738 		m->m_len = len;
2739 	}
2740 	switch(sopeop) {
2741 	case RSPQ_SOP_EOP:
2742 		ret = 1;
2743 		/* FALLTHROUGH */
2744 	case RSPQ_SOP:
2745 		mh->mh_head = mh->mh_tail = m;
2746 		m->m_pkthdr.len = len;
2747 		break;
2748 	case RSPQ_EOP:
2749 		ret = 1;
2750 		/* FALLTHROUGH */
2751 	case RSPQ_NSOP_NEOP:
2752 		if (mh->mh_tail == NULL) {
2753 			log(LOG_ERR, "discarding intermediate descriptor entry\n");
2754 			m_freem(m);
2755 			m = NULL;
2756 			break;
2757 		}
2758 		mh->mh_tail->m_next = m;
2759 		mh->mh_tail = m;
2760 		mh->mh_head->m_pkthdr.len += len;
2761 		break;
2762 	}
2763 	if (cxgb_debug && m != NULL)
2764 		printf("len=%d pktlen=%d\n", m->m_len, m->m_pkthdr.len);
2765 done:
2766 	if (++fl->cidx == fl->size)
2767 		fl->cidx = 0;
2768 
2769 	return (ret);
2770 }
2771 
2772 /**
2773  *	handle_rsp_cntrl_info - handles control information in a response
2774  *	@qs: the queue set corresponding to the response
2775  *	@flags: the response control flags
2776  *
2777  *	Handles the control information of an SGE response, such as GTS
2778  *	indications and completion credits for the queue set's Tx queues.
2779  *	HW coalesces credits, we don't do any extra SW coalescing.
2780  */
2781 static __inline void
2782 handle_rsp_cntrl_info(struct sge_qset *qs, uint32_t flags)
2783 {
2784 	unsigned int credits;
2785 
2786 #if USE_GTS
2787 	if (flags & F_RSPD_TXQ0_GTS)
2788 		clear_bit(TXQ_RUNNING, &qs->txq[TXQ_ETH].flags);
2789 #endif
2790 	credits = G_RSPD_TXQ0_CR(flags);
2791 	if (credits)
2792 		qs->txq[TXQ_ETH].processed += credits;
2793 
2794 	credits = G_RSPD_TXQ2_CR(flags);
2795 	if (credits)
2796 		qs->txq[TXQ_CTRL].processed += credits;
2797 
2798 # if USE_GTS
2799 	if (flags & F_RSPD_TXQ1_GTS)
2800 		clear_bit(TXQ_RUNNING, &qs->txq[TXQ_OFLD].flags);
2801 # endif
2802 	credits = G_RSPD_TXQ1_CR(flags);
2803 	if (credits)
2804 		qs->txq[TXQ_OFLD].processed += credits;
2805 
2806 }
2807 
2808 static void
2809 check_ring_db(adapter_t *adap, struct sge_qset *qs,
2810     unsigned int sleeping)
2811 {
2812 	;
2813 }
2814 
2815 /**
2816  *	process_responses - process responses from an SGE response queue
2817  *	@adap: the adapter
2818  *	@qs: the queue set to which the response queue belongs
2819  *	@budget: how many responses can be processed in this round
2820  *
2821  *	Process responses from an SGE response queue up to the supplied budget.
2822  *	Responses include received packets as well as credits and other events
2823  *	for the queues that belong to the response queue's queue set.
2824  *	A negative budget is effectively unlimited.
2825  *
2826  *	Additionally choose the interrupt holdoff time for the next interrupt
2827  *	on this queue.  If the system is under memory shortage use a fairly
2828  *	long delay to help recovery.
2829  */
2830 static int
2831 process_responses(adapter_t *adap, struct sge_qset *qs, int budget)
2832 {
2833 	struct sge_rspq *rspq = &qs->rspq;
2834 	struct rsp_desc *r = &rspq->desc[rspq->cidx];
2835 	int budget_left = budget;
2836 	unsigned int sleeping = 0;
2837 #if defined(INET6) || defined(INET)
2838 	int lro_enabled = qs->lro.enabled;
2839 	int skip_lro;
2840 	struct lro_ctrl *lro_ctrl = &qs->lro.ctrl;
2841 #endif
2842 	struct t3_mbuf_hdr *mh = &rspq->rspq_mh;
2843 #ifdef DEBUG
2844 	static int last_holdoff = 0;
2845 	if (cxgb_debug && rspq->holdoff_tmr != last_holdoff) {
2846 		printf("next_holdoff=%d\n", rspq->holdoff_tmr);
2847 		last_holdoff = rspq->holdoff_tmr;
2848 	}
2849 #endif
2850 	rspq->next_holdoff = rspq->holdoff_tmr;
2851 
2852 	while (__predict_true(budget_left && is_new_response(r, rspq))) {
2853 		int eth, eop = 0, ethpad = 0;
2854 		uint32_t flags = ntohl(r->flags);
2855 		uint32_t rss_hash = be32toh(r->rss_hdr.rss_hash_val);
2856 		uint8_t opcode = r->rss_hdr.opcode;
2857 
2858 		eth = (opcode == CPL_RX_PKT);
2859 
2860 		if (__predict_false(flags & F_RSPD_ASYNC_NOTIF)) {
2861 			struct mbuf *m;
2862 
2863 			if (cxgb_debug)
2864 				printf("async notification\n");
2865 
2866 			if (mh->mh_head == NULL) {
2867 				mh->mh_head = m_gethdr(M_NOWAIT, MT_DATA);
2868 				m = mh->mh_head;
2869 			} else {
2870 				m = m_gethdr(M_NOWAIT, MT_DATA);
2871 			}
2872 			if (m == NULL)
2873 				goto no_mem;
2874 
2875                         memcpy(mtod(m, char *), r, AN_PKT_SIZE);
2876 			m->m_len = m->m_pkthdr.len = AN_PKT_SIZE;
2877                         *mtod(m, uint8_t *) = CPL_ASYNC_NOTIF;
2878 			opcode = CPL_ASYNC_NOTIF;
2879 			eop = 1;
2880                         rspq->async_notif++;
2881 			goto skip;
2882 		} else if  (flags & F_RSPD_IMM_DATA_VALID) {
2883 			struct mbuf *m = m_gethdr(M_NOWAIT, MT_DATA);
2884 
2885 			if (m == NULL) {
2886 		no_mem:
2887 				rspq->next_holdoff = NOMEM_INTR_DELAY;
2888 				budget_left--;
2889 				break;
2890 			}
2891 			if (mh->mh_head == NULL)
2892 				mh->mh_head = m;
2893                         else
2894 				mh->mh_tail->m_next = m;
2895 			mh->mh_tail = m;
2896 
2897 			get_imm_packet(adap, r, m);
2898 			mh->mh_head->m_pkthdr.len += m->m_len;
2899 			eop = 1;
2900 			rspq->imm_data++;
2901 		} else if (r->len_cq) {
2902 			int drop_thresh = eth ? SGE_RX_DROP_THRES : 0;
2903 
2904 			eop = get_packet(adap, drop_thresh, qs, mh, r);
2905 			if (eop) {
2906 				if (r->rss_hdr.hash_type && !adap->timestamp) {
2907 					M_HASHTYPE_SET(mh->mh_head,
2908 					    M_HASHTYPE_OPAQUE_HASH);
2909 					mh->mh_head->m_pkthdr.flowid = rss_hash;
2910 				}
2911 			}
2912 
2913 			ethpad = 2;
2914 		} else {
2915 			rspq->pure_rsps++;
2916 		}
2917 	skip:
2918 		if (flags & RSPD_CTRL_MASK) {
2919 			sleeping |= flags & RSPD_GTS_MASK;
2920 			handle_rsp_cntrl_info(qs, flags);
2921 		}
2922 
2923 		if (!eth && eop) {
2924 			rspq->offload_pkts++;
2925 #ifdef TCP_OFFLOAD
2926 			adap->cpl_handler[opcode](qs, r, mh->mh_head);
2927 #else
2928 			m_freem(mh->mh_head);
2929 #endif
2930 			mh->mh_head = NULL;
2931 		} else if (eth && eop) {
2932 			struct mbuf *m = mh->mh_head;
2933 
2934 			t3_rx_eth(adap, m, ethpad);
2935 
2936 			/*
2937 			 * The T304 sends incoming packets on any qset.  If LRO
2938 			 * is also enabled, we could end up sending packet up
2939 			 * lro_ctrl->ifp's input.  That is incorrect.
2940 			 *
2941 			 * The mbuf's rcvif was derived from the cpl header and
2942 			 * is accurate.  Skip LRO and just use that.
2943 			 */
2944 #if defined(INET6) || defined(INET)
2945 			skip_lro = __predict_false(qs->port->ifp != m->m_pkthdr.rcvif);
2946 
2947 			if (lro_enabled && lro_ctrl->lro_cnt && !skip_lro
2948 			    && (tcp_lro_rx(lro_ctrl, m, 0) == 0)
2949 			    ) {
2950 				/* successfully queue'd for LRO */
2951 			} else
2952 #endif
2953 			{
2954 				/*
2955 				 * LRO not enabled, packet unsuitable for LRO,
2956 				 * or unable to queue.  Pass it up right now in
2957 				 * either case.
2958 				 */
2959 				struct ifnet *ifp = m->m_pkthdr.rcvif;
2960 				(*ifp->if_input)(ifp, m);
2961 			}
2962 			mh->mh_head = NULL;
2963 
2964 		}
2965 
2966 		r++;
2967 		if (__predict_false(++rspq->cidx == rspq->size)) {
2968 			rspq->cidx = 0;
2969 			rspq->gen ^= 1;
2970 			r = rspq->desc;
2971 		}
2972 
2973 		if (++rspq->credits >= 64) {
2974 			refill_rspq(adap, rspq, rspq->credits);
2975 			rspq->credits = 0;
2976 		}
2977 		__refill_fl_lt(adap, &qs->fl[0], 32);
2978 		__refill_fl_lt(adap, &qs->fl[1], 32);
2979 		--budget_left;
2980 	}
2981 
2982 #if defined(INET6) || defined(INET)
2983 	/* Flush LRO */
2984 	tcp_lro_flush_all(lro_ctrl);
2985 #endif
2986 
2987 	if (sleeping)
2988 		check_ring_db(adap, qs, sleeping);
2989 
2990 	mb();  /* commit Tx queue processed updates */
2991 	if (__predict_false(qs->txq_stopped > 1))
2992 		restart_tx(qs);
2993 
2994 	__refill_fl_lt(adap, &qs->fl[0], 512);
2995 	__refill_fl_lt(adap, &qs->fl[1], 512);
2996 	budget -= budget_left;
2997 	return (budget);
2998 }
2999 
3000 /*
3001  * A helper function that processes responses and issues GTS.
3002  */
3003 static __inline int
3004 process_responses_gts(adapter_t *adap, struct sge_rspq *rq)
3005 {
3006 	int work;
3007 	static int last_holdoff = 0;
3008 
3009 	work = process_responses(adap, rspq_to_qset(rq), -1);
3010 
3011 	if (cxgb_debug && (rq->next_holdoff != last_holdoff)) {
3012 		printf("next_holdoff=%d\n", rq->next_holdoff);
3013 		last_holdoff = rq->next_holdoff;
3014 	}
3015 	t3_write_reg(adap, A_SG_GTS, V_RSPQ(rq->cntxt_id) |
3016 	    V_NEWTIMER(rq->next_holdoff) | V_NEWINDEX(rq->cidx));
3017 
3018 	return (work);
3019 }
3020 
3021 #ifdef DEBUGNET
3022 int
3023 cxgb_debugnet_poll_rx(adapter_t *adap, struct sge_qset *qs)
3024 {
3025 
3026 	return (process_responses_gts(adap, &qs->rspq));
3027 }
3028 #endif
3029 
3030 /*
3031  * Interrupt handler for legacy INTx interrupts for T3B-based cards.
3032  * Handles data events from SGE response queues as well as error and other
3033  * async events as they all use the same interrupt pin.  We use one SGE
3034  * response queue per port in this mode and protect all response queues with
3035  * queue 0's lock.
3036  */
3037 void
3038 t3b_intr(void *data)
3039 {
3040 	uint32_t i, map;
3041 	adapter_t *adap = data;
3042 	struct sge_rspq *q0 = &adap->sge.qs[0].rspq;
3043 
3044 	t3_write_reg(adap, A_PL_CLI, 0);
3045 	map = t3_read_reg(adap, A_SG_DATA_INTR);
3046 
3047 	if (!map)
3048 		return;
3049 
3050 	if (__predict_false(map & F_ERRINTR)) {
3051 		t3_write_reg(adap, A_PL_INT_ENABLE0, 0);
3052 		(void) t3_read_reg(adap, A_PL_INT_ENABLE0);
3053 		taskqueue_enqueue(adap->tq, &adap->slow_intr_task);
3054 	}
3055 
3056 	mtx_lock(&q0->lock);
3057 	for_each_port(adap, i)
3058 	    if (map & (1 << i))
3059 			process_responses_gts(adap, &adap->sge.qs[i].rspq);
3060 	mtx_unlock(&q0->lock);
3061 }
3062 
3063 /*
3064  * The MSI interrupt handler.  This needs to handle data events from SGE
3065  * response queues as well as error and other async events as they all use
3066  * the same MSI vector.  We use one SGE response queue per port in this mode
3067  * and protect all response queues with queue 0's lock.
3068  */
3069 void
3070 t3_intr_msi(void *data)
3071 {
3072 	adapter_t *adap = data;
3073 	struct sge_rspq *q0 = &adap->sge.qs[0].rspq;
3074 	int i, new_packets = 0;
3075 
3076 	mtx_lock(&q0->lock);
3077 
3078 	for_each_port(adap, i)
3079 	    if (process_responses_gts(adap, &adap->sge.qs[i].rspq))
3080 		    new_packets = 1;
3081 	mtx_unlock(&q0->lock);
3082 	if (new_packets == 0) {
3083 		t3_write_reg(adap, A_PL_INT_ENABLE0, 0);
3084 		(void) t3_read_reg(adap, A_PL_INT_ENABLE0);
3085 		taskqueue_enqueue(adap->tq, &adap->slow_intr_task);
3086 	}
3087 }
3088 
3089 void
3090 t3_intr_msix(void *data)
3091 {
3092 	struct sge_qset *qs = data;
3093 	adapter_t *adap = qs->port->adapter;
3094 	struct sge_rspq *rspq = &qs->rspq;
3095 
3096 	if (process_responses_gts(adap, rspq) == 0)
3097 		rspq->unhandled_irqs++;
3098 }
3099 
3100 #define QDUMP_SBUF_SIZE		32 * 400
3101 static int
3102 t3_dump_rspq(SYSCTL_HANDLER_ARGS)
3103 {
3104 	struct sge_rspq *rspq;
3105 	struct sge_qset *qs;
3106 	int i, err, dump_end, idx;
3107 	struct sbuf *sb;
3108 	struct rsp_desc *rspd;
3109 	uint32_t data[4];
3110 
3111 	rspq = arg1;
3112 	qs = rspq_to_qset(rspq);
3113 	if (rspq->rspq_dump_count == 0)
3114 		return (0);
3115 	if (rspq->rspq_dump_count > RSPQ_Q_SIZE) {
3116 		log(LOG_WARNING,
3117 		    "dump count is too large %d\n", rspq->rspq_dump_count);
3118 		rspq->rspq_dump_count = 0;
3119 		return (EINVAL);
3120 	}
3121 	if (rspq->rspq_dump_start > (RSPQ_Q_SIZE-1)) {
3122 		log(LOG_WARNING,
3123 		    "dump start of %d is greater than queue size\n",
3124 		    rspq->rspq_dump_start);
3125 		rspq->rspq_dump_start = 0;
3126 		return (EINVAL);
3127 	}
3128 	err = t3_sge_read_rspq(qs->port->adapter, rspq->cntxt_id, data);
3129 	if (err)
3130 		return (err);
3131 	err = sysctl_wire_old_buffer(req, 0);
3132 	if (err)
3133 		return (err);
3134 	sb = sbuf_new_for_sysctl(NULL, NULL, QDUMP_SBUF_SIZE, req);
3135 
3136 	sbuf_printf(sb, " \n index=%u size=%u MSI-X/RspQ=%u intr enable=%u intr armed=%u\n",
3137 	    (data[0] & 0xffff), data[0] >> 16, ((data[2] >> 20) & 0x3f),
3138 	    ((data[2] >> 26) & 1), ((data[2] >> 27) & 1));
3139 	sbuf_printf(sb, " generation=%u CQ mode=%u FL threshold=%u\n",
3140 	    ((data[2] >> 28) & 1), ((data[2] >> 31) & 1), data[3]);
3141 
3142 	sbuf_printf(sb, " start=%d -> end=%d\n", rspq->rspq_dump_start,
3143 	    (rspq->rspq_dump_start + rspq->rspq_dump_count) & (RSPQ_Q_SIZE-1));
3144 
3145 	dump_end = rspq->rspq_dump_start + rspq->rspq_dump_count;
3146 	for (i = rspq->rspq_dump_start; i < dump_end; i++) {
3147 		idx = i & (RSPQ_Q_SIZE-1);
3148 
3149 		rspd = &rspq->desc[idx];
3150 		sbuf_printf(sb, "\tidx=%04d opcode=%02x cpu_idx=%x hash_type=%x cq_idx=%x\n",
3151 		    idx, rspd->rss_hdr.opcode, rspd->rss_hdr.cpu_idx,
3152 		    rspd->rss_hdr.hash_type, be16toh(rspd->rss_hdr.cq_idx));
3153 		sbuf_printf(sb, "\trss_hash_val=%x flags=%08x len_cq=%x intr_gen=%x\n",
3154 		    rspd->rss_hdr.rss_hash_val, be32toh(rspd->flags),
3155 		    be32toh(rspd->len_cq), rspd->intr_gen);
3156 	}
3157 
3158 	err = sbuf_finish(sb);
3159 	sbuf_delete(sb);
3160 	return (err);
3161 }
3162 
3163 static int
3164 t3_dump_txq_eth(SYSCTL_HANDLER_ARGS)
3165 {
3166 	struct sge_txq *txq;
3167 	struct sge_qset *qs;
3168 	int i, j, err, dump_end;
3169 	struct sbuf *sb;
3170 	struct tx_desc *txd;
3171 	uint32_t *WR, wr_hi, wr_lo, gen;
3172 	uint32_t data[4];
3173 
3174 	txq = arg1;
3175 	qs = txq_to_qset(txq, TXQ_ETH);
3176 	if (txq->txq_dump_count == 0) {
3177 		return (0);
3178 	}
3179 	if (txq->txq_dump_count > TX_ETH_Q_SIZE) {
3180 		log(LOG_WARNING,
3181 		    "dump count is too large %d\n", txq->txq_dump_count);
3182 		txq->txq_dump_count = 1;
3183 		return (EINVAL);
3184 	}
3185 	if (txq->txq_dump_start > (TX_ETH_Q_SIZE-1)) {
3186 		log(LOG_WARNING,
3187 		    "dump start of %d is greater than queue size\n",
3188 		    txq->txq_dump_start);
3189 		txq->txq_dump_start = 0;
3190 		return (EINVAL);
3191 	}
3192 	err = t3_sge_read_ecntxt(qs->port->adapter, qs->rspq.cntxt_id, data);
3193 	if (err)
3194 		return (err);
3195 	err = sysctl_wire_old_buffer(req, 0);
3196 	if (err)
3197 		return (err);
3198 	sb = sbuf_new_for_sysctl(NULL, NULL, QDUMP_SBUF_SIZE, req);
3199 
3200 	sbuf_printf(sb, " \n credits=%u GTS=%u index=%u size=%u rspq#=%u cmdq#=%u\n",
3201 	    (data[0] & 0x7fff), ((data[0] >> 15) & 1), (data[0] >> 16),
3202 	    (data[1] & 0xffff), ((data[3] >> 4) & 7), ((data[3] >> 7) & 1));
3203 	sbuf_printf(sb, " TUN=%u TOE=%u generation%u uP token=%u valid=%u\n",
3204 	    ((data[3] >> 8) & 1), ((data[3] >> 9) & 1), ((data[3] >> 10) & 1),
3205 	    ((data[3] >> 11) & 0xfffff), ((data[3] >> 31) & 1));
3206 	sbuf_printf(sb, " qid=%d start=%d -> end=%d\n", qs->idx,
3207 	    txq->txq_dump_start,
3208 	    (txq->txq_dump_start + txq->txq_dump_count) & (TX_ETH_Q_SIZE-1));
3209 
3210 	dump_end = txq->txq_dump_start + txq->txq_dump_count;
3211 	for (i = txq->txq_dump_start; i < dump_end; i++) {
3212 		txd = &txq->desc[i & (TX_ETH_Q_SIZE-1)];
3213 		WR = (uint32_t *)txd->flit;
3214 		wr_hi = ntohl(WR[0]);
3215 		wr_lo = ntohl(WR[1]);
3216 		gen = G_WR_GEN(wr_lo);
3217 
3218 		sbuf_printf(sb," wr_hi %08x wr_lo %08x gen %d\n",
3219 		    wr_hi, wr_lo, gen);
3220 		for (j = 2; j < 30; j += 4)
3221 			sbuf_printf(sb, "\t%08x %08x %08x %08x \n",
3222 			    WR[j], WR[j + 1], WR[j + 2], WR[j + 3]);
3223 
3224 	}
3225 	err = sbuf_finish(sb);
3226 	sbuf_delete(sb);
3227 	return (err);
3228 }
3229 
3230 static int
3231 t3_dump_txq_ctrl(SYSCTL_HANDLER_ARGS)
3232 {
3233 	struct sge_txq *txq;
3234 	struct sge_qset *qs;
3235 	int i, j, err, dump_end;
3236 	struct sbuf *sb;
3237 	struct tx_desc *txd;
3238 	uint32_t *WR, wr_hi, wr_lo, gen;
3239 
3240 	txq = arg1;
3241 	qs = txq_to_qset(txq, TXQ_CTRL);
3242 	if (txq->txq_dump_count == 0) {
3243 		return (0);
3244 	}
3245 	if (txq->txq_dump_count > 256) {
3246 		log(LOG_WARNING,
3247 		    "dump count is too large %d\n", txq->txq_dump_count);
3248 		txq->txq_dump_count = 1;
3249 		return (EINVAL);
3250 	}
3251 	if (txq->txq_dump_start > 255) {
3252 		log(LOG_WARNING,
3253 		    "dump start of %d is greater than queue size\n",
3254 		    txq->txq_dump_start);
3255 		txq->txq_dump_start = 0;
3256 		return (EINVAL);
3257 	}
3258 
3259 	err = sysctl_wire_old_buffer(req, 0);
3260 	if (err != 0)
3261 		return (err);
3262 	sb = sbuf_new_for_sysctl(NULL, NULL, QDUMP_SBUF_SIZE, req);
3263 	sbuf_printf(sb, " qid=%d start=%d -> end=%d\n", qs->idx,
3264 	    txq->txq_dump_start,
3265 	    (txq->txq_dump_start + txq->txq_dump_count) & 255);
3266 
3267 	dump_end = txq->txq_dump_start + txq->txq_dump_count;
3268 	for (i = txq->txq_dump_start; i < dump_end; i++) {
3269 		txd = &txq->desc[i & (255)];
3270 		WR = (uint32_t *)txd->flit;
3271 		wr_hi = ntohl(WR[0]);
3272 		wr_lo = ntohl(WR[1]);
3273 		gen = G_WR_GEN(wr_lo);
3274 
3275 		sbuf_printf(sb," wr_hi %08x wr_lo %08x gen %d\n",
3276 		    wr_hi, wr_lo, gen);
3277 		for (j = 2; j < 30; j += 4)
3278 			sbuf_printf(sb, "\t%08x %08x %08x %08x \n",
3279 			    WR[j], WR[j + 1], WR[j + 2], WR[j + 3]);
3280 
3281 	}
3282 	err = sbuf_finish(sb);
3283 	sbuf_delete(sb);
3284 	return (err);
3285 }
3286 
3287 static int
3288 t3_set_coalesce_usecs(SYSCTL_HANDLER_ARGS)
3289 {
3290 	adapter_t *sc = arg1;
3291 	struct qset_params *qsp = &sc->params.sge.qset[0];
3292 	int coalesce_usecs;
3293 	struct sge_qset *qs;
3294 	int i, j, err, nqsets = 0;
3295 	struct mtx *lock;
3296 
3297 	if ((sc->flags & FULL_INIT_DONE) == 0)
3298 		return (ENXIO);
3299 
3300 	coalesce_usecs = qsp->coalesce_usecs;
3301         err = sysctl_handle_int(oidp, &coalesce_usecs, arg2, req);
3302 
3303 	if (err != 0) {
3304 		return (err);
3305 	}
3306 	if (coalesce_usecs == qsp->coalesce_usecs)
3307 		return (0);
3308 
3309 	for (i = 0; i < sc->params.nports; i++)
3310 		for (j = 0; j < sc->port[i].nqsets; j++)
3311 			nqsets++;
3312 
3313 	coalesce_usecs = max(1, coalesce_usecs);
3314 
3315 	for (i = 0; i < nqsets; i++) {
3316 		qs = &sc->sge.qs[i];
3317 		qsp = &sc->params.sge.qset[i];
3318 		qsp->coalesce_usecs = coalesce_usecs;
3319 
3320 		lock = (sc->flags & USING_MSIX) ? &qs->rspq.lock :
3321 			    &sc->sge.qs[0].rspq.lock;
3322 
3323 		mtx_lock(lock);
3324 		t3_update_qset_coalesce(qs, qsp);
3325 		t3_write_reg(sc, A_SG_GTS, V_RSPQ(qs->rspq.cntxt_id) |
3326 		    V_NEWTIMER(qs->rspq.holdoff_tmr));
3327 		mtx_unlock(lock);
3328 	}
3329 
3330 	return (0);
3331 }
3332 
3333 static int
3334 t3_pkt_timestamp(SYSCTL_HANDLER_ARGS)
3335 {
3336 	adapter_t *sc = arg1;
3337 	int rc, timestamp;
3338 
3339 	if ((sc->flags & FULL_INIT_DONE) == 0)
3340 		return (ENXIO);
3341 
3342 	timestamp = sc->timestamp;
3343 	rc = sysctl_handle_int(oidp, &timestamp, arg2, req);
3344 
3345 	if (rc != 0)
3346 		return (rc);
3347 
3348 	if (timestamp != sc->timestamp) {
3349 		t3_set_reg_field(sc, A_TP_PC_CONFIG2, F_ENABLERXPKTTMSTPRSS,
3350 		    timestamp ? F_ENABLERXPKTTMSTPRSS : 0);
3351 		sc->timestamp = timestamp;
3352 	}
3353 
3354 	return (0);
3355 }
3356 
3357 void
3358 t3_add_attach_sysctls(adapter_t *sc)
3359 {
3360 	struct sysctl_ctx_list *ctx;
3361 	struct sysctl_oid_list *children;
3362 
3363 	ctx = device_get_sysctl_ctx(sc->dev);
3364 	children = SYSCTL_CHILDREN(device_get_sysctl_tree(sc->dev));
3365 
3366 	/* random information */
3367 	SYSCTL_ADD_STRING(ctx, children, OID_AUTO,
3368 	    "firmware_version",
3369 	    CTLFLAG_RD, sc->fw_version,
3370 	    0, "firmware version");
3371 	SYSCTL_ADD_UINT(ctx, children, OID_AUTO,
3372 	    "hw_revision",
3373 	    CTLFLAG_RD, &sc->params.rev,
3374 	    0, "chip model");
3375 	SYSCTL_ADD_STRING(ctx, children, OID_AUTO,
3376 	    "port_types",
3377 	    CTLFLAG_RD, sc->port_types,
3378 	    0, "type of ports");
3379 	SYSCTL_ADD_INT(ctx, children, OID_AUTO,
3380 	    "enable_debug",
3381 	    CTLFLAG_RW, &cxgb_debug,
3382 	    0, "enable verbose debugging output");
3383 	SYSCTL_ADD_UQUAD(ctx, children, OID_AUTO, "tunq_coalesce",
3384 	    CTLFLAG_RD, &sc->tunq_coalesce,
3385 	    "#tunneled packets freed");
3386 	SYSCTL_ADD_INT(ctx, children, OID_AUTO,
3387 	    "txq_overrun",
3388 	    CTLFLAG_RD, &txq_fills,
3389 	    0, "#times txq overrun");
3390 	SYSCTL_ADD_UINT(ctx, children, OID_AUTO,
3391 	    "core_clock",
3392 	    CTLFLAG_RD, &sc->params.vpd.cclk,
3393 	    0, "core clock frequency (in KHz)");
3394 }
3395 
3396 
3397 static const char *rspq_name = "rspq";
3398 static const char *txq_names[] =
3399 {
3400 	"txq_eth",
3401 	"txq_ofld",
3402 	"txq_ctrl"
3403 };
3404 
3405 static int
3406 sysctl_handle_macstat(SYSCTL_HANDLER_ARGS)
3407 {
3408 	struct port_info *p = arg1;
3409 	uint64_t *parg;
3410 
3411 	if (!p)
3412 		return (EINVAL);
3413 
3414 	cxgb_refresh_stats(p);
3415 	parg = (uint64_t *) ((uint8_t *)&p->mac.stats + arg2);
3416 
3417 	return (sysctl_handle_64(oidp, parg, 0, req));
3418 }
3419 
3420 void
3421 t3_add_configured_sysctls(adapter_t *sc)
3422 {
3423 	struct sysctl_ctx_list *ctx;
3424 	struct sysctl_oid_list *children;
3425 	int i, j;
3426 
3427 	ctx = device_get_sysctl_ctx(sc->dev);
3428 	children = SYSCTL_CHILDREN(device_get_sysctl_tree(sc->dev));
3429 
3430 	SYSCTL_ADD_PROC(ctx, children, OID_AUTO,
3431 	    "intr_coal",
3432 	    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, sc,
3433 	    0, t3_set_coalesce_usecs,
3434 	    "I", "interrupt coalescing timer (us)");
3435 
3436 	SYSCTL_ADD_PROC(ctx, children, OID_AUTO,
3437 	    "pkt_timestamp",
3438 	    CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, sc,
3439 	    0, t3_pkt_timestamp,
3440 	    "I", "provide packet timestamp instead of connection hash");
3441 
3442 	for (i = 0; i < sc->params.nports; i++) {
3443 		struct port_info *pi = &sc->port[i];
3444 		struct sysctl_oid *poid;
3445 		struct sysctl_oid_list *poidlist;
3446 		struct mac_stats *mstats = &pi->mac.stats;
3447 
3448 		snprintf(pi->namebuf, PORT_NAME_LEN, "port%d", i);
3449 		poid = SYSCTL_ADD_NODE(ctx, children, OID_AUTO,
3450 		    pi->namebuf, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
3451 		    "port statistics");
3452 		poidlist = SYSCTL_CHILDREN(poid);
3453 		SYSCTL_ADD_UINT(ctx, poidlist, OID_AUTO,
3454 		    "nqsets", CTLFLAG_RD, &pi->nqsets,
3455 		    0, "#queue sets");
3456 
3457 		for (j = 0; j < pi->nqsets; j++) {
3458 			struct sge_qset *qs = &sc->sge.qs[pi->first_qset + j];
3459 			struct sysctl_oid *qspoid, *rspqpoid, *txqpoid,
3460 					  *ctrlqpoid, *lropoid;
3461 			struct sysctl_oid_list *qspoidlist, *rspqpoidlist,
3462 					       *txqpoidlist, *ctrlqpoidlist,
3463 					       *lropoidlist;
3464 			struct sge_txq *txq = &qs->txq[TXQ_ETH];
3465 
3466 			snprintf(qs->namebuf, QS_NAME_LEN, "qs%d", j);
3467 
3468 			qspoid = SYSCTL_ADD_NODE(ctx, poidlist, OID_AUTO,
3469 			    qs->namebuf, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
3470 			    "qset statistics");
3471 			qspoidlist = SYSCTL_CHILDREN(qspoid);
3472 
3473 			SYSCTL_ADD_UINT(ctx, qspoidlist, OID_AUTO, "fl0_empty",
3474 					CTLFLAG_RD, &qs->fl[0].empty, 0,
3475 					"freelist #0 empty");
3476 			SYSCTL_ADD_UINT(ctx, qspoidlist, OID_AUTO, "fl1_empty",
3477 					CTLFLAG_RD, &qs->fl[1].empty, 0,
3478 					"freelist #1 empty");
3479 
3480 			rspqpoid = SYSCTL_ADD_NODE(ctx, qspoidlist, OID_AUTO,
3481 			    rspq_name, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
3482 			    "rspq statistics");
3483 			rspqpoidlist = SYSCTL_CHILDREN(rspqpoid);
3484 
3485 			txqpoid = SYSCTL_ADD_NODE(ctx, qspoidlist, OID_AUTO,
3486 			    txq_names[0], CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
3487 			    "txq statistics");
3488 			txqpoidlist = SYSCTL_CHILDREN(txqpoid);
3489 
3490 			ctrlqpoid = SYSCTL_ADD_NODE(ctx, qspoidlist, OID_AUTO,
3491 			    txq_names[2], CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
3492 			    "ctrlq statistics");
3493 			ctrlqpoidlist = SYSCTL_CHILDREN(ctrlqpoid);
3494 
3495 			lropoid = SYSCTL_ADD_NODE(ctx, qspoidlist, OID_AUTO,
3496 			    "lro_stats", CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
3497 			    "LRO statistics");
3498 			lropoidlist = SYSCTL_CHILDREN(lropoid);
3499 
3500 			SYSCTL_ADD_UINT(ctx, rspqpoidlist, OID_AUTO, "size",
3501 			    CTLFLAG_RD, &qs->rspq.size,
3502 			    0, "#entries in response queue");
3503 			SYSCTL_ADD_UINT(ctx, rspqpoidlist, OID_AUTO, "cidx",
3504 			    CTLFLAG_RD, &qs->rspq.cidx,
3505 			    0, "consumer index");
3506 			SYSCTL_ADD_UINT(ctx, rspqpoidlist, OID_AUTO, "credits",
3507 			    CTLFLAG_RD, &qs->rspq.credits,
3508 			    0, "#credits");
3509 			SYSCTL_ADD_UINT(ctx, rspqpoidlist, OID_AUTO, "starved",
3510 			    CTLFLAG_RD, &qs->rspq.starved,
3511 			    0, "#times starved");
3512 			SYSCTL_ADD_UAUTO(ctx, rspqpoidlist, OID_AUTO, "phys_addr",
3513 			    CTLFLAG_RD, &qs->rspq.phys_addr,
3514 			    "physical_address_of the queue");
3515 			SYSCTL_ADD_UINT(ctx, rspqpoidlist, OID_AUTO, "dump_start",
3516 			    CTLFLAG_RW, &qs->rspq.rspq_dump_start,
3517 			    0, "start rspq dump entry");
3518 			SYSCTL_ADD_UINT(ctx, rspqpoidlist, OID_AUTO, "dump_count",
3519 			    CTLFLAG_RW, &qs->rspq.rspq_dump_count,
3520 			    0, "#rspq entries to dump");
3521 			SYSCTL_ADD_PROC(ctx, rspqpoidlist, OID_AUTO, "qdump",
3522 			    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
3523 			    &qs->rspq, 0, t3_dump_rspq, "A",
3524 			    "dump of the response queue");
3525 
3526 			SYSCTL_ADD_UQUAD(ctx, txqpoidlist, OID_AUTO, "dropped",
3527 			    CTLFLAG_RD, &qs->txq[TXQ_ETH].txq_mr->br_drops,
3528 			    "#tunneled packets dropped");
3529 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "sendqlen",
3530 			    CTLFLAG_RD, &qs->txq[TXQ_ETH].sendq.mq_len,
3531 			    0, "#tunneled packets waiting to be sent");
3532 #if 0
3533 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "queue_pidx",
3534 			    CTLFLAG_RD, (uint32_t *)(uintptr_t)&qs->txq[TXQ_ETH].txq_mr.br_prod,
3535 			    0, "#tunneled packets queue producer index");
3536 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "queue_cidx",
3537 			    CTLFLAG_RD, (uint32_t *)(uintptr_t)&qs->txq[TXQ_ETH].txq_mr.br_cons,
3538 			    0, "#tunneled packets queue consumer index");
3539 #endif
3540 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "processed",
3541 			    CTLFLAG_RD, &qs->txq[TXQ_ETH].processed,
3542 			    0, "#tunneled packets processed by the card");
3543 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "cleaned",
3544 			    CTLFLAG_RD, &txq->cleaned,
3545 			    0, "#tunneled packets cleaned");
3546 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "in_use",
3547 			    CTLFLAG_RD, &txq->in_use,
3548 			    0, "#tunneled packet slots in use");
3549 			SYSCTL_ADD_UQUAD(ctx, txqpoidlist, OID_AUTO, "frees",
3550 			    CTLFLAG_RD, &txq->txq_frees,
3551 			    "#tunneled packets freed");
3552 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "skipped",
3553 			    CTLFLAG_RD, &txq->txq_skipped,
3554 			    0, "#tunneled packet descriptors skipped");
3555 			SYSCTL_ADD_UQUAD(ctx, txqpoidlist, OID_AUTO, "coalesced",
3556 			    CTLFLAG_RD, &txq->txq_coalesced,
3557 			    "#tunneled packets coalesced");
3558 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "enqueued",
3559 			    CTLFLAG_RD, &txq->txq_enqueued,
3560 			    0, "#tunneled packets enqueued to hardware");
3561 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "stopped_flags",
3562 			    CTLFLAG_RD, &qs->txq_stopped,
3563 			    0, "tx queues stopped");
3564 			SYSCTL_ADD_UAUTO(ctx, txqpoidlist, OID_AUTO, "phys_addr",
3565 			    CTLFLAG_RD, &txq->phys_addr,
3566 			    "physical_address_of the queue");
3567 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "qgen",
3568 			    CTLFLAG_RW, &qs->txq[TXQ_ETH].gen,
3569 			    0, "txq generation");
3570 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "hw_cidx",
3571 			    CTLFLAG_RD, &txq->cidx,
3572 			    0, "hardware queue cidx");
3573 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "hw_pidx",
3574 			    CTLFLAG_RD, &txq->pidx,
3575 			    0, "hardware queue pidx");
3576 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "dump_start",
3577 			    CTLFLAG_RW, &qs->txq[TXQ_ETH].txq_dump_start,
3578 			    0, "txq start idx for dump");
3579 			SYSCTL_ADD_UINT(ctx, txqpoidlist, OID_AUTO, "dump_count",
3580 			    CTLFLAG_RW, &qs->txq[TXQ_ETH].txq_dump_count,
3581 			    0, "txq #entries to dump");
3582 			SYSCTL_ADD_PROC(ctx, txqpoidlist, OID_AUTO, "qdump",
3583 			    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
3584 			    &qs->txq[TXQ_ETH], 0, t3_dump_txq_eth, "A",
3585 			    "dump of the transmit queue");
3586 
3587 			SYSCTL_ADD_UINT(ctx, ctrlqpoidlist, OID_AUTO, "dump_start",
3588 			    CTLFLAG_RW, &qs->txq[TXQ_CTRL].txq_dump_start,
3589 			    0, "ctrlq start idx for dump");
3590 			SYSCTL_ADD_UINT(ctx, ctrlqpoidlist, OID_AUTO, "dump_count",
3591 			    CTLFLAG_RW, &qs->txq[TXQ_CTRL].txq_dump_count,
3592 			    0, "ctrl #entries to dump");
3593 			SYSCTL_ADD_PROC(ctx, ctrlqpoidlist, OID_AUTO, "qdump",
3594 			    CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
3595 			    &qs->txq[TXQ_CTRL], 0, t3_dump_txq_ctrl, "A",
3596 			    "dump of the transmit queue");
3597 
3598 			SYSCTL_ADD_U64(ctx, lropoidlist, OID_AUTO, "lro_queued",
3599 			    CTLFLAG_RD, &qs->lro.ctrl.lro_queued, 0, NULL);
3600 			SYSCTL_ADD_U64(ctx, lropoidlist, OID_AUTO, "lro_flushed",
3601 			    CTLFLAG_RD, &qs->lro.ctrl.lro_flushed, 0, NULL);
3602 			SYSCTL_ADD_U64(ctx, lropoidlist, OID_AUTO, "lro_bad_csum",
3603 			    CTLFLAG_RD, &qs->lro.ctrl.lro_bad_csum, 0, NULL);
3604 			SYSCTL_ADD_INT(ctx, lropoidlist, OID_AUTO, "lro_cnt",
3605 			    CTLFLAG_RD, &qs->lro.ctrl.lro_cnt, 0, NULL);
3606 		}
3607 
3608 		/* Now add a node for mac stats. */
3609 		poid = SYSCTL_ADD_NODE(ctx, poidlist, OID_AUTO, "mac_stats",
3610 		    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "MAC statistics");
3611 		poidlist = SYSCTL_CHILDREN(poid);
3612 
3613 		/*
3614 		 * We (ab)use the length argument (arg2) to pass on the offset
3615 		 * of the data that we are interested in.  This is only required
3616 		 * for the quad counters that are updated from the hardware (we
3617 		 * make sure that we return the latest value).
3618 		 * sysctl_handle_macstat first updates *all* the counters from
3619 		 * the hardware, and then returns the latest value of the
3620 		 * requested counter.  Best would be to update only the
3621 		 * requested counter from hardware, but t3_mac_update_stats()
3622 		 * hides all the register details and we don't want to dive into
3623 		 * all that here.
3624 		 */
3625 #define CXGB_SYSCTL_ADD_QUAD(a)	SYSCTL_ADD_OID(ctx, poidlist, OID_AUTO, #a, \
3626     CTLTYPE_U64 | CTLFLAG_RD | CTLFLAG_NEEDGIANT, pi, \
3627     offsetof(struct mac_stats, a), sysctl_handle_macstat, "QU", 0)
3628 		CXGB_SYSCTL_ADD_QUAD(tx_octets);
3629 		CXGB_SYSCTL_ADD_QUAD(tx_octets_bad);
3630 		CXGB_SYSCTL_ADD_QUAD(tx_frames);
3631 		CXGB_SYSCTL_ADD_QUAD(tx_mcast_frames);
3632 		CXGB_SYSCTL_ADD_QUAD(tx_bcast_frames);
3633 		CXGB_SYSCTL_ADD_QUAD(tx_pause);
3634 		CXGB_SYSCTL_ADD_QUAD(tx_deferred);
3635 		CXGB_SYSCTL_ADD_QUAD(tx_late_collisions);
3636 		CXGB_SYSCTL_ADD_QUAD(tx_total_collisions);
3637 		CXGB_SYSCTL_ADD_QUAD(tx_excess_collisions);
3638 		CXGB_SYSCTL_ADD_QUAD(tx_underrun);
3639 		CXGB_SYSCTL_ADD_QUAD(tx_len_errs);
3640 		CXGB_SYSCTL_ADD_QUAD(tx_mac_internal_errs);
3641 		CXGB_SYSCTL_ADD_QUAD(tx_excess_deferral);
3642 		CXGB_SYSCTL_ADD_QUAD(tx_fcs_errs);
3643 		CXGB_SYSCTL_ADD_QUAD(tx_frames_64);
3644 		CXGB_SYSCTL_ADD_QUAD(tx_frames_65_127);
3645 		CXGB_SYSCTL_ADD_QUAD(tx_frames_128_255);
3646 		CXGB_SYSCTL_ADD_QUAD(tx_frames_256_511);
3647 		CXGB_SYSCTL_ADD_QUAD(tx_frames_512_1023);
3648 		CXGB_SYSCTL_ADD_QUAD(tx_frames_1024_1518);
3649 		CXGB_SYSCTL_ADD_QUAD(tx_frames_1519_max);
3650 		CXGB_SYSCTL_ADD_QUAD(rx_octets);
3651 		CXGB_SYSCTL_ADD_QUAD(rx_octets_bad);
3652 		CXGB_SYSCTL_ADD_QUAD(rx_frames);
3653 		CXGB_SYSCTL_ADD_QUAD(rx_mcast_frames);
3654 		CXGB_SYSCTL_ADD_QUAD(rx_bcast_frames);
3655 		CXGB_SYSCTL_ADD_QUAD(rx_pause);
3656 		CXGB_SYSCTL_ADD_QUAD(rx_fcs_errs);
3657 		CXGB_SYSCTL_ADD_QUAD(rx_align_errs);
3658 		CXGB_SYSCTL_ADD_QUAD(rx_symbol_errs);
3659 		CXGB_SYSCTL_ADD_QUAD(rx_data_errs);
3660 		CXGB_SYSCTL_ADD_QUAD(rx_sequence_errs);
3661 		CXGB_SYSCTL_ADD_QUAD(rx_runt);
3662 		CXGB_SYSCTL_ADD_QUAD(rx_jabber);
3663 		CXGB_SYSCTL_ADD_QUAD(rx_short);
3664 		CXGB_SYSCTL_ADD_QUAD(rx_too_long);
3665 		CXGB_SYSCTL_ADD_QUAD(rx_mac_internal_errs);
3666 		CXGB_SYSCTL_ADD_QUAD(rx_cong_drops);
3667 		CXGB_SYSCTL_ADD_QUAD(rx_frames_64);
3668 		CXGB_SYSCTL_ADD_QUAD(rx_frames_65_127);
3669 		CXGB_SYSCTL_ADD_QUAD(rx_frames_128_255);
3670 		CXGB_SYSCTL_ADD_QUAD(rx_frames_256_511);
3671 		CXGB_SYSCTL_ADD_QUAD(rx_frames_512_1023);
3672 		CXGB_SYSCTL_ADD_QUAD(rx_frames_1024_1518);
3673 		CXGB_SYSCTL_ADD_QUAD(rx_frames_1519_max);
3674 #undef CXGB_SYSCTL_ADD_QUAD
3675 
3676 #define CXGB_SYSCTL_ADD_ULONG(a) SYSCTL_ADD_ULONG(ctx, poidlist, OID_AUTO, #a, \
3677     CTLFLAG_RD, &mstats->a, 0)
3678 		CXGB_SYSCTL_ADD_ULONG(tx_fifo_parity_err);
3679 		CXGB_SYSCTL_ADD_ULONG(rx_fifo_parity_err);
3680 		CXGB_SYSCTL_ADD_ULONG(tx_fifo_urun);
3681 		CXGB_SYSCTL_ADD_ULONG(rx_fifo_ovfl);
3682 		CXGB_SYSCTL_ADD_ULONG(serdes_signal_loss);
3683 		CXGB_SYSCTL_ADD_ULONG(xaui_pcs_ctc_err);
3684 		CXGB_SYSCTL_ADD_ULONG(xaui_pcs_align_change);
3685 		CXGB_SYSCTL_ADD_ULONG(num_toggled);
3686 		CXGB_SYSCTL_ADD_ULONG(num_resets);
3687 		CXGB_SYSCTL_ADD_ULONG(link_faults);
3688 #undef CXGB_SYSCTL_ADD_ULONG
3689 	}
3690 }
3691 
3692 /**
3693  *	t3_get_desc - dump an SGE descriptor for debugging purposes
3694  *	@qs: the queue set
3695  *	@qnum: identifies the specific queue (0..2: Tx, 3:response, 4..5: Rx)
3696  *	@idx: the descriptor index in the queue
3697  *	@data: where to dump the descriptor contents
3698  *
3699  *	Dumps the contents of a HW descriptor of an SGE queue.  Returns the
3700  *	size of the descriptor.
3701  */
3702 int
3703 t3_get_desc(const struct sge_qset *qs, unsigned int qnum, unsigned int idx,
3704 		unsigned char *data)
3705 {
3706 	if (qnum >= 6)
3707 		return (EINVAL);
3708 
3709 	if (qnum < 3) {
3710 		if (!qs->txq[qnum].desc || idx >= qs->txq[qnum].size)
3711 			return -EINVAL;
3712 		memcpy(data, &qs->txq[qnum].desc[idx], sizeof(struct tx_desc));
3713 		return sizeof(struct tx_desc);
3714 	}
3715 
3716 	if (qnum == 3) {
3717 		if (!qs->rspq.desc || idx >= qs->rspq.size)
3718 			return (EINVAL);
3719 		memcpy(data, &qs->rspq.desc[idx], sizeof(struct rsp_desc));
3720 		return sizeof(struct rsp_desc);
3721 	}
3722 
3723 	qnum -= 4;
3724 	if (!qs->fl[qnum].desc || idx >= qs->fl[qnum].size)
3725 		return (EINVAL);
3726 	memcpy(data, &qs->fl[qnum].desc[idx], sizeof(struct rx_desc));
3727 	return sizeof(struct rx_desc);
3728 }
3729