xref: /freebsd/sys/dev/cxgbe/iw_cxgbe/t4.h (revision a2aef24aa3c8458e4036735dd6928b4ef77294e5)
1 /*
2  * Copyright (c) 2009-2013 Chelsio, Inc. All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *      - Redistributions in binary form must reproduce the above
18  *        copyright notice, this list of conditions and the following
19  *        disclaimer in the documentation and/or other materials
20  *        provided with the distribution.
21  *
22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
23  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
24  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
25  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
26  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
27  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
28  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
29  * SOFTWARE.
30  *
31  * $FreeBSD$
32  */
33 #ifndef __T4_H__
34 #define __T4_H__
35 
36 /*
37  * Fixme: Adding missing defines
38  */
39 #define SGE_PF_KDOORBELL 0x0
40 #define  QID_MASK    0xffff8000U
41 #define  QID_SHIFT   15
42 #define  QID(x)      ((x) << QID_SHIFT)
43 #define  DBPRIO      0x00004000U
44 #define  PIDX_MASK   0x00003fffU
45 #define  PIDX_SHIFT  0
46 #define  PIDX(x)     ((x) << PIDX_SHIFT)
47 
48 #define SGE_PF_GTS 0x4
49 #define  INGRESSQID_MASK   0xffff0000U
50 #define  INGRESSQID_SHIFT  16
51 #define  INGRESSQID(x)     ((x) << INGRESSQID_SHIFT)
52 #define  TIMERREG_MASK     0x0000e000U
53 #define  TIMERREG_SHIFT    13
54 #define  TIMERREG(x)       ((x) << TIMERREG_SHIFT)
55 #define  SEINTARM_MASK     0x00001000U
56 #define  SEINTARM_SHIFT    12
57 #define  SEINTARM(x)       ((x) << SEINTARM_SHIFT)
58 #define  CIDXINC_MASK      0x00000fffU
59 #define  CIDXINC_SHIFT     0
60 #define  CIDXINC(x)        ((x) << CIDXINC_SHIFT)
61 
62 #define T4_MAX_NUM_PD 65536
63 #define T4_MAX_EQ_SIZE 65520
64 #define T4_MAX_IQ_SIZE 65520
65 #define T4_MAX_RQ_SIZE(n) (8192 - (n) - 1)
66 #define T4_MAX_SQ_SIZE(n) (T4_MAX_EQ_SIZE - (n) - 1)
67 #define T4_MAX_QP_DEPTH(n) (T4_MAX_RQ_SIZE(n))
68 #define T4_MAX_CQ_DEPTH (T4_MAX_IQ_SIZE - 2)
69 #define T4_MAX_MR_SIZE (~0ULL - 1)
70 #define T4_PAGESIZE_MASK 0xffffffff000  /* 4KB-8TB */
71 #define T4_STAG_UNSET 0xffffffff
72 #define T4_FW_MAJ 0
73 #define A_PCIE_MA_SYNC 0x30b4
74 
75 struct t4_status_page {
76 	__be32 rsvd1;	/* flit 0 - hw owns */
77 	__be16 rsvd2;
78 	__be16 qid;
79 	__be16 cidx;
80 	__be16 pidx;
81 	u8 qp_err;	/* flit 1 - sw owns */
82 	u8 db_off;
83 	u8 pad;
84 	u16 host_wq_pidx;
85 	u16 host_cidx;
86 	u16 host_pidx;
87 };
88 
89 #define T4_EQ_ENTRY_SIZE 64
90 
91 #define T4_SQ_NUM_SLOTS 5
92 #define T4_SQ_NUM_BYTES (T4_EQ_ENTRY_SIZE * T4_SQ_NUM_SLOTS)
93 #define T4_MAX_SEND_SGE ((T4_SQ_NUM_BYTES - sizeof(struct fw_ri_send_wr) - \
94 			sizeof(struct fw_ri_isgl)) / sizeof(struct fw_ri_sge))
95 #define T4_MAX_SEND_INLINE ((T4_SQ_NUM_BYTES - sizeof(struct fw_ri_send_wr) - \
96 			sizeof(struct fw_ri_immd)))
97 #define T4_MAX_WRITE_INLINE ((T4_SQ_NUM_BYTES - \
98 			sizeof(struct fw_ri_rdma_write_wr) - \
99 			sizeof(struct fw_ri_immd)))
100 #define T4_MAX_WRITE_SGE ((T4_SQ_NUM_BYTES - \
101 			sizeof(struct fw_ri_rdma_write_wr) - \
102 			sizeof(struct fw_ri_isgl)) / sizeof(struct fw_ri_sge))
103 #define T4_MAX_FR_IMMD ((T4_SQ_NUM_BYTES - sizeof(struct fw_ri_fr_nsmr_wr) - \
104 			sizeof(struct fw_ri_immd)) & ~31UL)
105 #define T4_MAX_FR_DEPTH (T4_MAX_FR_IMMD / sizeof(u64))
106 
107 #define T4_RQ_NUM_SLOTS 2
108 #define T4_RQ_NUM_BYTES (T4_EQ_ENTRY_SIZE * T4_RQ_NUM_SLOTS)
109 #define T4_MAX_RECV_SGE 4
110 
111 union t4_wr {
112 	struct fw_ri_res_wr res;
113 	struct fw_ri_wr ri;
114 	struct fw_ri_rdma_write_wr write;
115 	struct fw_ri_send_wr send;
116 	struct fw_ri_rdma_read_wr read;
117 	struct fw_ri_bind_mw_wr bind;
118 	struct fw_ri_fr_nsmr_wr fr;
119 	struct fw_ri_inv_lstag_wr inv;
120 	struct t4_status_page status;
121 	__be64 flits[T4_EQ_ENTRY_SIZE / sizeof(__be64) * T4_SQ_NUM_SLOTS];
122 };
123 
124 union t4_recv_wr {
125 	struct fw_ri_recv_wr recv;
126 	struct t4_status_page status;
127 	__be64 flits[T4_EQ_ENTRY_SIZE / sizeof(__be64) * T4_RQ_NUM_SLOTS];
128 };
129 
130 static inline void init_wr_hdr(union t4_wr *wqe, u16 wrid,
131 			       enum fw_wr_opcodes opcode, u8 flags, u8 len16)
132 {
133 	wqe->send.opcode = (u8)opcode;
134 	wqe->send.flags = flags;
135 	wqe->send.wrid = wrid;
136 	wqe->send.r1[0] = 0;
137 	wqe->send.r1[1] = 0;
138 	wqe->send.r1[2] = 0;
139 	wqe->send.len16 = len16;
140 }
141 
142 /* CQE/AE status codes */
143 #define T4_ERR_SUCCESS                     0x0
144 #define T4_ERR_STAG                        0x1	/* STAG invalid: either the */
145 						/* STAG is offlimt, being 0, */
146 						/* or STAG_key mismatch */
147 #define T4_ERR_PDID                        0x2	/* PDID mismatch */
148 #define T4_ERR_QPID                        0x3	/* QPID mismatch */
149 #define T4_ERR_ACCESS                      0x4	/* Invalid access right */
150 #define T4_ERR_WRAP                        0x5	/* Wrap error */
151 #define T4_ERR_BOUND                       0x6	/* base and bounds voilation */
152 #define T4_ERR_INVALIDATE_SHARED_MR        0x7	/* attempt to invalidate a  */
153 						/* shared memory region */
154 #define T4_ERR_INVALIDATE_MR_WITH_MW_BOUND 0x8	/* attempt to invalidate a  */
155 						/* shared memory region */
156 #define T4_ERR_ECC                         0x9	/* ECC error detected */
157 #define T4_ERR_ECC_PSTAG                   0xA	/* ECC error detected when  */
158 						/* reading PSTAG for a MW  */
159 						/* Invalidate */
160 #define T4_ERR_PBL_ADDR_BOUND              0xB	/* pbl addr out of bounds:  */
161 						/* software error */
162 #define T4_ERR_SWFLUSH			   0xC	/* SW FLUSHED */
163 #define T4_ERR_CRC                         0x10 /* CRC error */
164 #define T4_ERR_MARKER                      0x11 /* Marker error */
165 #define T4_ERR_PDU_LEN_ERR                 0x12 /* invalid PDU length */
166 #define T4_ERR_OUT_OF_RQE                  0x13 /* out of RQE */
167 #define T4_ERR_DDP_VERSION                 0x14 /* wrong DDP version */
168 #define T4_ERR_RDMA_VERSION                0x15 /* wrong RDMA version */
169 #define T4_ERR_OPCODE                      0x16 /* invalid rdma opcode */
170 #define T4_ERR_DDP_QUEUE_NUM               0x17 /* invalid ddp queue number */
171 #define T4_ERR_MSN                         0x18 /* MSN error */
172 #define T4_ERR_TBIT                        0x19 /* tag bit not set correctly */
173 #define T4_ERR_MO                          0x1A /* MO not 0 for TERMINATE  */
174 						/* or READ_REQ */
175 #define T4_ERR_MSN_GAP                     0x1B
176 #define T4_ERR_MSN_RANGE                   0x1C
177 #define T4_ERR_IRD_OVERFLOW                0x1D
178 #define T4_ERR_RQE_ADDR_BOUND              0x1E /* RQE addr out of bounds:  */
179 						/* software error */
180 #define T4_ERR_INTERNAL_ERR                0x1F /* internal error (opcode  */
181 						/* mismatch) */
182 /*
183  * CQE defs
184  */
185 struct t4_cqe {
186 	__be32 header;
187 	__be32 len;
188 	union {
189 		struct {
190 			__be32 stag;
191 			__be32 msn;
192 		} rcqe;
193 		struct {
194 			u32 nada1;
195 			u16 nada2;
196 			u16 cidx;
197 		} scqe;
198 		struct {
199 			__be32 wrid_hi;
200 			__be32 wrid_low;
201 		} gen;
202 		u64 drain_cookie;
203 	} u;
204 	__be64 reserved;
205 	__be64 bits_type_ts;
206 };
207 
208 /* macros for flit 0 of the cqe */
209 
210 #define S_CQE_QPID        12
211 #define M_CQE_QPID        0xFFFFF
212 #define G_CQE_QPID(x)     ((((x) >> S_CQE_QPID)) & M_CQE_QPID)
213 #define V_CQE_QPID(x)	  ((x)<<S_CQE_QPID)
214 
215 #define S_CQE_SWCQE       11
216 #define M_CQE_SWCQE       0x1
217 #define G_CQE_SWCQE(x)    ((((x) >> S_CQE_SWCQE)) & M_CQE_SWCQE)
218 #define V_CQE_SWCQE(x)	  ((x)<<S_CQE_SWCQE)
219 
220 #define S_CQE_STATUS      5
221 #define M_CQE_STATUS      0x1F
222 #define G_CQE_STATUS(x)   ((((x) >> S_CQE_STATUS)) & M_CQE_STATUS)
223 #define V_CQE_STATUS(x)   ((x)<<S_CQE_STATUS)
224 
225 #define S_CQE_TYPE        4
226 #define M_CQE_TYPE        0x1
227 #define G_CQE_TYPE(x)     ((((x) >> S_CQE_TYPE)) & M_CQE_TYPE)
228 #define V_CQE_TYPE(x)     ((x)<<S_CQE_TYPE)
229 
230 #define S_CQE_OPCODE      0
231 #define M_CQE_OPCODE      0xF
232 #define G_CQE_OPCODE(x)   ((((x) >> S_CQE_OPCODE)) & M_CQE_OPCODE)
233 #define V_CQE_OPCODE(x)   ((x)<<S_CQE_OPCODE)
234 
235 #define SW_CQE(x)         (G_CQE_SWCQE(be32_to_cpu((x)->header)))
236 #define CQE_QPID(x)       (G_CQE_QPID(be32_to_cpu((x)->header)))
237 #define CQE_TYPE(x)       (G_CQE_TYPE(be32_to_cpu((x)->header)))
238 #define SQ_TYPE(x)	  (CQE_TYPE((x)))
239 #define RQ_TYPE(x)	  (!CQE_TYPE((x)))
240 #define CQE_STATUS(x)     (G_CQE_STATUS(be32_to_cpu((x)->header)))
241 #define CQE_OPCODE(x)     (G_CQE_OPCODE(be32_to_cpu((x)->header)))
242 
243 #define CQE_SEND_OPCODE(x)(\
244 	(G_CQE_OPCODE(be32_to_cpu((x)->header)) == FW_RI_SEND) || \
245 	(G_CQE_OPCODE(be32_to_cpu((x)->header)) == FW_RI_SEND_WITH_SE) || \
246 	(G_CQE_OPCODE(be32_to_cpu((x)->header)) == FW_RI_SEND_WITH_INV) || \
247 	(G_CQE_OPCODE(be32_to_cpu((x)->header)) == FW_RI_SEND_WITH_SE_INV))
248 
249 #define CQE_LEN(x)        (be32_to_cpu((x)->len))
250 
251 /* used for RQ completion processing */
252 #define CQE_WRID_STAG(x)  (be32_to_cpu((x)->u.rcqe.stag))
253 #define CQE_WRID_MSN(x)   (be32_to_cpu((x)->u.rcqe.msn))
254 
255 /* used for SQ completion processing */
256 #define CQE_WRID_SQ_IDX(x)	((x)->u.scqe.cidx)
257 
258 /* generic accessor macros */
259 #define CQE_WRID_HI(x)		((x)->u.gen.wrid_hi)
260 #define CQE_WRID_LOW(x)		((x)->u.gen.wrid_low)
261 #define CQE_DRAIN_COOKIE(x)	(x)->u.drain_cookie;
262 
263 /* macros for flit 3 of the cqe */
264 #define S_CQE_GENBIT	63
265 #define M_CQE_GENBIT	0x1
266 #define G_CQE_GENBIT(x)	(((x) >> S_CQE_GENBIT) & M_CQE_GENBIT)
267 #define V_CQE_GENBIT(x) ((x)<<S_CQE_GENBIT)
268 
269 #define S_CQE_OVFBIT	62
270 #define M_CQE_OVFBIT	0x1
271 #define G_CQE_OVFBIT(x)	((((x) >> S_CQE_OVFBIT)) & M_CQE_OVFBIT)
272 
273 #define S_CQE_IQTYPE	60
274 #define M_CQE_IQTYPE	0x3
275 #define G_CQE_IQTYPE(x)	((((x) >> S_CQE_IQTYPE)) & M_CQE_IQTYPE)
276 
277 #define M_CQE_TS	0x0fffffffffffffffULL
278 #define G_CQE_TS(x)	((x) & M_CQE_TS)
279 
280 #define CQE_OVFBIT(x)	((unsigned)G_CQE_OVFBIT(be64_to_cpu((x)->bits_type_ts)))
281 #define CQE_GENBIT(x)	((unsigned)G_CQE_GENBIT(be64_to_cpu((x)->bits_type_ts)))
282 #define CQE_TS(x)	(G_CQE_TS(be64_to_cpu((x)->bits_type_ts)))
283 
284 struct t4_swsqe {
285 	u64			wr_id;
286 	struct t4_cqe		cqe;
287 	int			read_len;
288 	int			opcode;
289 	int			complete;
290 	int			signaled;
291 	u16			idx;
292 };
293 
294 struct t4_sq {
295 	union t4_wr *queue;
296 	bus_addr_t dma_addr;
297 	DECLARE_PCI_UNMAP_ADDR(mapping);
298 	unsigned long phys_addr;
299 	struct t4_swsqe *sw_sq;
300 	struct t4_swsqe *oldest_read;
301 	u64 udb;
302 	size_t memsize;
303 	u32 qid;
304 	u16 in_use;
305 	u16 size;
306 	u16 cidx;
307 	u16 pidx;
308 	u16 wq_pidx;
309 	u16 flags;
310 };
311 
312 struct t4_swrqe {
313 	u64 wr_id;
314 };
315 
316 struct t4_rq {
317 	union  t4_recv_wr *queue;
318 	bus_addr_t dma_addr;
319 	DECLARE_PCI_UNMAP_ADDR(mapping);
320 	struct t4_swrqe *sw_rq;
321 	u64 udb;
322 	size_t memsize;
323 	u32 qid;
324 	u32 msn;
325 	u32 rqt_hwaddr;
326 	u16 rqt_size;
327 	u16 in_use;
328 	u16 size;
329 	u16 cidx;
330 	u16 pidx;
331 	u16 wq_pidx;
332 };
333 
334 struct t4_wq {
335 	struct t4_sq sq;
336 	struct t4_rq rq;
337 	void __iomem *db;
338 	void __iomem *gts;
339 	struct c4iw_rdev *rdev;
340 };
341 
342 static inline int t4_rqes_posted(struct t4_wq *wq)
343 {
344 	return wq->rq.in_use;
345 }
346 
347 static inline int t4_rq_empty(struct t4_wq *wq)
348 {
349 	return wq->rq.in_use == 0;
350 }
351 
352 static inline int t4_rq_full(struct t4_wq *wq)
353 {
354 	return wq->rq.in_use == (wq->rq.size - 1);
355 }
356 
357 static inline u32 t4_rq_avail(struct t4_wq *wq)
358 {
359 	return wq->rq.size - 1 - wq->rq.in_use;
360 }
361 
362 static inline void t4_rq_produce(struct t4_wq *wq, u8 len16)
363 {
364 	wq->rq.in_use++;
365 	if (++wq->rq.pidx == wq->rq.size)
366 		wq->rq.pidx = 0;
367 	wq->rq.wq_pidx += DIV_ROUND_UP(len16*16, T4_EQ_ENTRY_SIZE);
368 	if (wq->rq.wq_pidx >= wq->rq.size * T4_RQ_NUM_SLOTS)
369 		wq->rq.wq_pidx %= wq->rq.size * T4_RQ_NUM_SLOTS;
370 }
371 
372 static inline void t4_rq_consume(struct t4_wq *wq)
373 {
374 	wq->rq.in_use--;
375 	wq->rq.msn++;
376 	if (++wq->rq.cidx == wq->rq.size)
377 		wq->rq.cidx = 0;
378 }
379 
380 static inline u16 t4_rq_host_wq_pidx(struct t4_wq *wq)
381 {
382 	return wq->rq.queue[wq->rq.size].status.host_wq_pidx;
383 }
384 
385 static inline u16 t4_rq_wq_size(struct t4_wq *wq)
386 {
387 		return wq->rq.size * T4_RQ_NUM_SLOTS;
388 }
389 
390 static inline int t4_sq_empty(struct t4_wq *wq)
391 {
392 	return wq->sq.in_use == 0;
393 }
394 
395 static inline int t4_sq_full(struct t4_wq *wq)
396 {
397 	return wq->sq.in_use == (wq->sq.size - 1);
398 }
399 
400 static inline u32 t4_sq_avail(struct t4_wq *wq)
401 {
402 	return wq->sq.size - 1 - wq->sq.in_use;
403 }
404 
405 static inline void t4_sq_produce(struct t4_wq *wq, u8 len16)
406 {
407 	wq->sq.in_use++;
408 	if (++wq->sq.pidx == wq->sq.size)
409 		wq->sq.pidx = 0;
410 	wq->sq.wq_pidx += DIV_ROUND_UP(len16*16, T4_EQ_ENTRY_SIZE);
411 	if (wq->sq.wq_pidx >= wq->sq.size * T4_SQ_NUM_SLOTS)
412 		wq->sq.wq_pidx %= wq->sq.size * T4_SQ_NUM_SLOTS;
413 }
414 
415 static inline void t4_sq_consume(struct t4_wq *wq)
416 {
417 	wq->sq.in_use--;
418 	if (++wq->sq.cidx == wq->sq.size)
419 		wq->sq.cidx = 0;
420 }
421 
422 static inline u16 t4_sq_host_wq_pidx(struct t4_wq *wq)
423 {
424 	return wq->sq.queue[wq->sq.size].status.host_wq_pidx;
425 }
426 
427 static inline u16 t4_sq_wq_size(struct t4_wq *wq)
428 {
429 		return wq->sq.size * T4_SQ_NUM_SLOTS;
430 }
431 
432 static inline void t4_ring_sq_db(struct t4_wq *wq, u16 inc)
433 {
434 	wmb();
435 	writel(QID(wq->sq.qid) | PIDX(inc), wq->db);
436 }
437 
438 static inline void t4_ring_rq_db(struct t4_wq *wq, u16 inc)
439 {
440 	wmb();
441 	writel(QID(wq->rq.qid) | PIDX(inc), wq->db);
442 }
443 
444 static inline int t4_wq_in_error(struct t4_wq *wq)
445 {
446 	return wq->rq.queue[wq->rq.size].status.qp_err;
447 }
448 
449 static inline void t4_set_wq_in_error(struct t4_wq *wq)
450 {
451 	wq->rq.queue[wq->rq.size].status.qp_err = 1;
452 }
453 
454 struct t4_cq {
455 	struct t4_cqe *queue;
456 	bus_addr_t dma_addr;
457 	DECLARE_PCI_UNMAP_ADDR(mapping);
458 	struct t4_cqe *sw_queue;
459 	void __iomem *gts;
460 	struct c4iw_rdev *rdev;
461 	u64 ugts;
462 	size_t memsize;
463 	__be64 bits_type_ts;
464 	u32 cqid;
465 	u16 size; /* including status page */
466 	u16 cidx;
467 	u16 sw_pidx;
468 	u16 sw_cidx;
469 	u16 sw_in_use;
470 	u16 cidx_inc;
471 	u8 gen;
472 	u8 error;
473 };
474 
475 static inline int t4_arm_cq(struct t4_cq *cq, int se)
476 {
477 	u32 val;
478 
479 	while (cq->cidx_inc > CIDXINC_MASK) {
480 		val = SEINTARM(0) | CIDXINC(CIDXINC_MASK) | TIMERREG(7) |
481 		      INGRESSQID(cq->cqid);
482 		writel(val, cq->gts);
483 		cq->cidx_inc -= CIDXINC_MASK;
484 	}
485 	val = SEINTARM(se) | CIDXINC(cq->cidx_inc) | TIMERREG(6) |
486 	      INGRESSQID(cq->cqid);
487 	writel(val, cq->gts);
488 	cq->cidx_inc = 0;
489 	return 0;
490 }
491 
492 static inline void t4_swcq_produce(struct t4_cq *cq)
493 {
494 	cq->sw_in_use++;
495 	if (++cq->sw_pidx == cq->size)
496 		cq->sw_pidx = 0;
497 }
498 
499 static inline void t4_swcq_consume(struct t4_cq *cq)
500 {
501 	cq->sw_in_use--;
502 	if (++cq->sw_cidx == cq->size)
503 		cq->sw_cidx = 0;
504 }
505 
506 static inline void t4_hwcq_consume(struct t4_cq *cq)
507 {
508 	cq->bits_type_ts = cq->queue[cq->cidx].bits_type_ts;
509 	if (++cq->cidx_inc == (cq->size >> 4) || cq->cidx_inc == M_CIDXINC) {
510 		u32 val;
511 
512 		val = SEINTARM(0) | CIDXINC(cq->cidx_inc) | TIMERREG(7) |
513 		      INGRESSQID(cq->cqid);
514 		writel(val, cq->gts);
515 		cq->cidx_inc = 0;
516 	}
517 	if (++cq->cidx == cq->size) {
518 		cq->cidx = 0;
519 		cq->gen ^= 1;
520 	}
521 }
522 
523 static inline int t4_valid_cqe(struct t4_cq *cq, struct t4_cqe *cqe)
524 {
525 	return (CQE_GENBIT(cqe) == cq->gen);
526 }
527 
528 static inline int t4_next_hw_cqe(struct t4_cq *cq, struct t4_cqe **cqe)
529 {
530 	int ret;
531 	u16 prev_cidx;
532 
533 	if (cq->cidx == 0)
534 		prev_cidx = cq->size - 1;
535 	else
536 		prev_cidx = cq->cidx - 1;
537 
538 	if (cq->queue[prev_cidx].bits_type_ts != cq->bits_type_ts) {
539 		ret = -EOVERFLOW;
540 		cq->error = 1;
541 		printk(KERN_ERR MOD "cq overflow cqid %u\n", cq->cqid);
542 	} else if (t4_valid_cqe(cq, &cq->queue[cq->cidx])) {
543 		*cqe = &cq->queue[cq->cidx];
544 		ret = 0;
545 	} else
546 		ret = -ENODATA;
547 	return ret;
548 }
549 
550 static inline struct t4_cqe *t4_next_sw_cqe(struct t4_cq *cq)
551 {
552 	if (cq->sw_in_use)
553 		return &cq->sw_queue[cq->sw_cidx];
554 	return NULL;
555 }
556 
557 static inline int t4_next_cqe(struct t4_cq *cq, struct t4_cqe **cqe)
558 {
559 	int ret = 0;
560 
561 	if (cq->error)
562 		ret = -ENODATA;
563 	else if (cq->sw_in_use)
564 		*cqe = &cq->sw_queue[cq->sw_cidx];
565 	else
566 		ret = t4_next_hw_cqe(cq, cqe);
567 	return ret;
568 }
569 
570 static inline int t4_cq_in_error(struct t4_cq *cq)
571 {
572 	return ((struct t4_status_page *)&cq->queue[cq->size])->qp_err;
573 }
574 
575 static inline void t4_set_cq_in_error(struct t4_cq *cq)
576 {
577 	((struct t4_status_page *)&cq->queue[cq->size])->qp_err = 1;
578 }
579 #endif
580