xref: /linux/drivers/scsi/esas2r/esas2r_io.c (revision 307797159ac25fe5a2048bf5c6a5718298edca57)
1 /*
2  *  linux/drivers/scsi/esas2r/esas2r_io.c
3  *      For use with ATTO ExpressSAS R6xx SAS/SATA RAID controllers
4  *
5  *  Copyright (c) 2001-2013 ATTO Technology, Inc.
6  *  (mailto:linuxdrivers@attotech.com)mpt3sas/mpt3sas_trigger_diag.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * as published by the Free Software Foundation; either version 2
11  * of the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * NO WARRANTY
19  * THE PROGRAM IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OR
20  * CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED INCLUDING, WITHOUT
21  * LIMITATION, ANY WARRANTIES OR CONDITIONS OF TITLE, NON-INFRINGEMENT,
22  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Each Recipient is
23  * solely responsible for determining the appropriateness of using and
24  * distributing the Program and assumes all risks associated with its
25  * exercise of rights under this Agreement, including but not limited to
26  * the risks and costs of program errors, damage to or loss of data,
27  * programs or equipment, and unavailability or interruption of operations.
28  *
29  * DISCLAIMER OF LIABILITY
30  * NEITHER RECIPIENT NOR ANY CONTRIBUTORS SHALL HAVE ANY LIABILITY FOR ANY
31  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32  * DAMAGES (INCLUDING WITHOUT LIMITATION LOST PROFITS), HOWEVER CAUSED AND
33  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
34  * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
35  * USE OR DISTRIBUTION OF THE PROGRAM OR THE EXERCISE OF ANY RIGHTS GRANTED
36  * HEREUNDER, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES
37  *
38  * You should have received a copy of the GNU General Public License
39  * along with this program; if not, write to the Free Software
40  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
41  * USA.
42  */
43 
44 #include "esas2r.h"
45 
46 void esas2r_start_request(struct esas2r_adapter *a, struct esas2r_request *rq)
47 {
48 	struct esas2r_target *t = NULL;
49 	struct esas2r_request *startrq = rq;
50 	unsigned long flags;
51 
52 	if (unlikely(test_bit(AF_DEGRADED_MODE, &a->flags) ||
53 		     test_bit(AF_POWER_DOWN, &a->flags))) {
54 		if (rq->vrq->scsi.function == VDA_FUNC_SCSI)
55 			rq->req_stat = RS_SEL2;
56 		else
57 			rq->req_stat = RS_DEGRADED;
58 	} else if (likely(rq->vrq->scsi.function == VDA_FUNC_SCSI)) {
59 		t = a->targetdb + rq->target_id;
60 
61 		if (unlikely(t >= a->targetdb_end
62 			     || !(t->flags & TF_USED))) {
63 			rq->req_stat = RS_SEL;
64 		} else {
65 			/* copy in the target ID. */
66 			rq->vrq->scsi.target_id = cpu_to_le16(t->virt_targ_id);
67 
68 			/*
69 			 * Test if we want to report RS_SEL for missing target.
70 			 * Note that if AF_DISC_PENDING is set than this will
71 			 * go on the defer queue.
72 			 */
73 			if (unlikely(t->target_state != TS_PRESENT &&
74 				     !test_bit(AF_DISC_PENDING, &a->flags)))
75 				rq->req_stat = RS_SEL;
76 		}
77 	}
78 
79 	if (unlikely(rq->req_stat != RS_PENDING)) {
80 		esas2r_complete_request(a, rq);
81 		return;
82 	}
83 
84 	esas2r_trace("rq=%p", rq);
85 	esas2r_trace("rq->vrq->scsi.handle=%x", rq->vrq->scsi.handle);
86 
87 	if (rq->vrq->scsi.function == VDA_FUNC_SCSI) {
88 		esas2r_trace("rq->target_id=%d", rq->target_id);
89 		esas2r_trace("rq->vrq->scsi.flags=%x", rq->vrq->scsi.flags);
90 	}
91 
92 	spin_lock_irqsave(&a->queue_lock, flags);
93 
94 	if (likely(list_empty(&a->defer_list) &&
95 		   !test_bit(AF_CHPRST_PENDING, &a->flags) &&
96 		   !test_bit(AF_FLASHING, &a->flags) &&
97 		   !test_bit(AF_DISC_PENDING, &a->flags)))
98 		esas2r_local_start_request(a, startrq);
99 	else
100 		list_add_tail(&startrq->req_list, &a->defer_list);
101 
102 	spin_unlock_irqrestore(&a->queue_lock, flags);
103 }
104 
105 /*
106  * Starts the specified request.  all requests have RS_PENDING set when this
107  * routine is called.  The caller is usually esas2r_start_request, but
108  * esas2r_do_deferred_processes will start request that are deferred.
109  *
110  * The caller must ensure that requests can be started.
111  *
112  * esas2r_start_request will defer a request if there are already requests
113  * waiting or there is a chip reset pending.  once the reset condition clears,
114  * esas2r_do_deferred_processes will call this function to start the request.
115  *
116  * When a request is started, it is placed on the active list and queued to
117  * the controller.
118  */
119 void esas2r_local_start_request(struct esas2r_adapter *a,
120 				struct esas2r_request *rq)
121 {
122 	esas2r_trace_enter();
123 	esas2r_trace("rq=%p", rq);
124 	esas2r_trace("rq->vrq:%p", rq->vrq);
125 	esas2r_trace("rq->vrq_md->phys_addr:%x", rq->vrq_md->phys_addr);
126 
127 	if (unlikely(rq->vrq->scsi.function == VDA_FUNC_FLASH
128 		     && rq->vrq->flash.sub_func == VDA_FLASH_COMMIT))
129 		set_bit(AF_FLASHING, &a->flags);
130 
131 	list_add_tail(&rq->req_list, &a->active_list);
132 	esas2r_start_vda_request(a, rq);
133 	esas2r_trace_exit();
134 	return;
135 }
136 
137 void esas2r_start_vda_request(struct esas2r_adapter *a,
138 			      struct esas2r_request *rq)
139 {
140 	struct esas2r_inbound_list_source_entry *element;
141 	u32 dw;
142 
143 	rq->req_stat = RS_STARTED;
144 	/*
145 	 * Calculate the inbound list entry location and the current state of
146 	 * toggle bit.
147 	 */
148 	a->last_write++;
149 	if (a->last_write >= a->list_size) {
150 		a->last_write = 0;
151 		/* update the toggle bit */
152 		if (test_bit(AF_COMM_LIST_TOGGLE, &a->flags))
153 			clear_bit(AF_COMM_LIST_TOGGLE, &a->flags);
154 		else
155 			set_bit(AF_COMM_LIST_TOGGLE, &a->flags);
156 	}
157 
158 	element =
159 		(struct esas2r_inbound_list_source_entry *)a->inbound_list_md.
160 		virt_addr
161 		+ a->last_write;
162 
163 	/* Set the VDA request size if it was never modified */
164 	if (rq->vda_req_sz == RQ_SIZE_DEFAULT)
165 		rq->vda_req_sz = (u16)(a->max_vdareq_size / sizeof(u32));
166 
167 	element->address = cpu_to_le64(rq->vrq_md->phys_addr);
168 	element->length = cpu_to_le32(rq->vda_req_sz);
169 
170 	/* Update the write pointer */
171 	dw = a->last_write;
172 
173 	if (test_bit(AF_COMM_LIST_TOGGLE, &a->flags))
174 		dw |= MU_ILW_TOGGLE;
175 
176 	esas2r_trace("rq->vrq->scsi.handle:%x", rq->vrq->scsi.handle);
177 	esas2r_trace("dw:%x", dw);
178 	esas2r_trace("rq->vda_req_sz:%x", rq->vda_req_sz);
179 	esas2r_write_register_dword(a, MU_IN_LIST_WRITE, dw);
180 }
181 
182 /*
183  * Build the scatter/gather list for an I/O request according to the
184  * specifications placed in the s/g context.  The caller must initialize
185  * context prior to the initial call by calling esas2r_sgc_init().
186  */
187 bool esas2r_build_sg_list_sge(struct esas2r_adapter *a,
188 			      struct esas2r_sg_context *sgc)
189 {
190 	struct esas2r_request *rq = sgc->first_req;
191 	union atto_vda_req *vrq = rq->vrq;
192 
193 	while (sgc->length) {
194 		u32 rem = 0;
195 		u64 addr;
196 		u32 len;
197 
198 		len = (*sgc->get_phys_addr)(sgc, &addr);
199 
200 		if (unlikely(len == 0))
201 			return false;
202 
203 		/* if current length is more than what's left, stop there */
204 		if (unlikely(len > sgc->length))
205 			len = sgc->length;
206 
207 another_entry:
208 		/* limit to a round number less than the maximum length */
209 		if (len > SGE_LEN_MAX) {
210 			/*
211 			 * Save the remainder of the split.  Whenever we limit
212 			 * an entry we come back around to build entries out
213 			 * of the leftover.  We do this to prevent multiple
214 			 * calls to the get_phys_addr() function for an SGE
215 			 * that is too large.
216 			 */
217 			rem = len - SGE_LEN_MAX;
218 			len = SGE_LEN_MAX;
219 		}
220 
221 		/* See if we need to allocate a new SGL */
222 		if (unlikely(sgc->sge.a64.curr > sgc->sge.a64.limit)) {
223 			u8 sgelen;
224 			struct esas2r_mem_desc *sgl;
225 
226 			/*
227 			 * If no SGls are available, return failure.  The
228 			 * caller can call us later with the current context
229 			 * to pick up here.
230 			 */
231 			sgl = esas2r_alloc_sgl(a);
232 
233 			if (unlikely(sgl == NULL))
234 				return false;
235 
236 			/* Calculate the length of the last SGE filled in */
237 			sgelen = (u8)((u8 *)sgc->sge.a64.curr
238 				      - (u8 *)sgc->sge.a64.last);
239 
240 			/*
241 			 * Copy the last SGE filled in to the first entry of
242 			 * the new SGL to make room for the chain entry.
243 			 */
244 			memcpy(sgl->virt_addr, sgc->sge.a64.last, sgelen);
245 
246 			/* Figure out the new curr pointer in the new segment */
247 			sgc->sge.a64.curr =
248 				(struct atto_vda_sge *)((u8 *)sgl->virt_addr +
249 							sgelen);
250 
251 			/* Set the limit pointer and build the chain entry */
252 			sgc->sge.a64.limit =
253 				(struct atto_vda_sge *)((u8 *)sgl->virt_addr
254 							+ sgl_page_size
255 							- sizeof(struct
256 								 atto_vda_sge));
257 			sgc->sge.a64.last->length = cpu_to_le32(
258 				SGE_CHAIN | SGE_ADDR_64);
259 			sgc->sge.a64.last->address =
260 				cpu_to_le64(sgl->phys_addr);
261 
262 			/*
263 			 * Now, if there was a previous chain entry, then
264 			 * update it to contain the length of this segment
265 			 * and size of this chain.  otherwise this is the
266 			 * first SGL, so set the chain_offset in the request.
267 			 */
268 			if (sgc->sge.a64.chain) {
269 				sgc->sge.a64.chain->length |=
270 					cpu_to_le32(
271 						((u8 *)(sgc->sge.a64.
272 							last + 1)
273 						 - (u8 *)rq->sg_table->
274 						 virt_addr)
275 						+ sizeof(struct atto_vda_sge) *
276 						LOBIT(SGE_CHAIN_SZ));
277 			} else {
278 				vrq->scsi.chain_offset = (u8)
279 							 ((u8 *)sgc->
280 							  sge.a64.last -
281 							  (u8 *)vrq);
282 
283 				/*
284 				 * This is the first SGL, so set the
285 				 * chain_offset and the VDA request size in
286 				 * the request.
287 				 */
288 				rq->vda_req_sz =
289 					(vrq->scsi.chain_offset +
290 					 sizeof(struct atto_vda_sge) +
291 					 3)
292 					/ sizeof(u32);
293 			}
294 
295 			/*
296 			 * Remember this so when we get a new SGL filled in we
297 			 * can update the length of this chain entry.
298 			 */
299 			sgc->sge.a64.chain = sgc->sge.a64.last;
300 
301 			/* Now link the new SGL onto the primary request. */
302 			list_add(&sgl->next_desc, &rq->sg_table_head);
303 		}
304 
305 		/* Update last one filled in */
306 		sgc->sge.a64.last = sgc->sge.a64.curr;
307 
308 		/* Build the new SGE and update the S/G context */
309 		sgc->sge.a64.curr->length = cpu_to_le32(SGE_ADDR_64 | len);
310 		sgc->sge.a64.curr->address = cpu_to_le32(addr);
311 		sgc->sge.a64.curr++;
312 		sgc->cur_offset += len;
313 		sgc->length -= len;
314 
315 		/*
316 		 * Check if we previously split an entry.  If so we have to
317 		 * pick up where we left off.
318 		 */
319 		if (rem) {
320 			addr += len;
321 			len = rem;
322 			rem = 0;
323 			goto another_entry;
324 		}
325 	}
326 
327 	/* Mark the end of the SGL */
328 	sgc->sge.a64.last->length |= cpu_to_le32(SGE_LAST);
329 
330 	/*
331 	 * If there was a previous chain entry, update the length to indicate
332 	 * the length of this last segment.
333 	 */
334 	if (sgc->sge.a64.chain) {
335 		sgc->sge.a64.chain->length |= cpu_to_le32(
336 			((u8 *)(sgc->sge.a64.curr) -
337 			 (u8 *)rq->sg_table->virt_addr));
338 	} else {
339 		u16 reqsize;
340 
341 		/*
342 		 * The entire VDA request was not used so lets
343 		 * set the size of the VDA request to be DMA'd
344 		 */
345 		reqsize =
346 			((u16)((u8 *)sgc->sge.a64.last - (u8 *)vrq)
347 			 + sizeof(struct atto_vda_sge) + 3) / sizeof(u32);
348 
349 		/*
350 		 * Only update the request size if it is bigger than what is
351 		 * already there.  We can come in here twice for some management
352 		 * commands.
353 		 */
354 		if (reqsize > rq->vda_req_sz)
355 			rq->vda_req_sz = reqsize;
356 	}
357 	return true;
358 }
359 
360 
361 /*
362  * Create PRD list for each I-block consumed by the command. This routine
363  * determines how much data is required from each I-block being consumed
364  * by the command. The first and last I-blocks can be partials and all of
365  * the I-blocks in between are for a full I-block of data.
366  *
367  * The interleave size is used to determine the number of bytes in the 1st
368  * I-block and the remaining I-blocks are what remeains.
369  */
370 static bool esas2r_build_prd_iblk(struct esas2r_adapter *a,
371 				  struct esas2r_sg_context *sgc)
372 {
373 	struct esas2r_request *rq = sgc->first_req;
374 	u64 addr;
375 	u32 len;
376 	struct esas2r_mem_desc *sgl;
377 	u32 numchain = 1;
378 	u32 rem = 0;
379 
380 	while (sgc->length) {
381 		/* Get the next address/length pair */
382 
383 		len = (*sgc->get_phys_addr)(sgc, &addr);
384 
385 		if (unlikely(len == 0))
386 			return false;
387 
388 		/* If current length is more than what's left, stop there */
389 
390 		if (unlikely(len > sgc->length))
391 			len = sgc->length;
392 
393 another_entry:
394 		/* Limit to a round number less than the maximum length */
395 
396 		if (len > PRD_LEN_MAX) {
397 			/*
398 			 * Save the remainder of the split.  whenever we limit
399 			 * an entry we come back around to build entries out
400 			 * of the leftover.  We do this to prevent multiple
401 			 * calls to the get_phys_addr() function for an SGE
402 			 * that is too large.
403 			 */
404 			rem = len - PRD_LEN_MAX;
405 			len = PRD_LEN_MAX;
406 		}
407 
408 		/* See if we need to allocate a new SGL */
409 		if (sgc->sge.prd.sge_cnt == 0) {
410 			if (len == sgc->length) {
411 				/*
412 				 * We only have 1 PRD entry left.
413 				 * It can be placed where the chain
414 				 * entry would have gone
415 				 */
416 
417 				/* Build the simple SGE */
418 				sgc->sge.prd.curr->ctl_len = cpu_to_le32(
419 					PRD_DATA | len);
420 				sgc->sge.prd.curr->address = cpu_to_le64(addr);
421 
422 				/* Adjust length related fields */
423 				sgc->cur_offset += len;
424 				sgc->length -= len;
425 
426 				/* We use the reserved chain entry for data */
427 				numchain = 0;
428 
429 				break;
430 			}
431 
432 			if (sgc->sge.prd.chain) {
433 				/*
434 				 * Fill # of entries of current SGL in previous
435 				 * chain the length of this current SGL may not
436 				 * full.
437 				 */
438 
439 				sgc->sge.prd.chain->ctl_len |= cpu_to_le32(
440 					sgc->sge.prd.sgl_max_cnt);
441 			}
442 
443 			/*
444 			 * If no SGls are available, return failure.  The
445 			 * caller can call us later with the current context
446 			 * to pick up here.
447 			 */
448 
449 			sgl = esas2r_alloc_sgl(a);
450 
451 			if (unlikely(sgl == NULL))
452 				return false;
453 
454 			/*
455 			 * Link the new SGL onto the chain
456 			 * They are in reverse order
457 			 */
458 			list_add(&sgl->next_desc, &rq->sg_table_head);
459 
460 			/*
461 			 * An SGL was just filled in and we are starting
462 			 * a new SGL. Prime the chain of the ending SGL with
463 			 * info that points to the new SGL. The length gets
464 			 * filled in when the new SGL is filled or ended
465 			 */
466 
467 			sgc->sge.prd.chain = sgc->sge.prd.curr;
468 
469 			sgc->sge.prd.chain->ctl_len = cpu_to_le32(PRD_CHAIN);
470 			sgc->sge.prd.chain->address =
471 				cpu_to_le64(sgl->phys_addr);
472 
473 			/*
474 			 * Start a new segment.
475 			 * Take one away and save for chain SGE
476 			 */
477 
478 			sgc->sge.prd.curr =
479 				(struct atto_physical_region_description *)sgl
480 				->
481 				virt_addr;
482 			sgc->sge.prd.sge_cnt = sgc->sge.prd.sgl_max_cnt - 1;
483 		}
484 
485 		sgc->sge.prd.sge_cnt--;
486 		/* Build the simple SGE */
487 		sgc->sge.prd.curr->ctl_len = cpu_to_le32(PRD_DATA | len);
488 		sgc->sge.prd.curr->address = cpu_to_le64(addr);
489 
490 		/* Used another element.  Point to the next one */
491 
492 		sgc->sge.prd.curr++;
493 
494 		/* Adjust length related fields */
495 
496 		sgc->cur_offset += len;
497 		sgc->length -= len;
498 
499 		/*
500 		 * Check if we previously split an entry.  If so we have to
501 		 * pick up where we left off.
502 		 */
503 
504 		if (rem) {
505 			addr += len;
506 			len = rem;
507 			rem = 0;
508 			goto another_entry;
509 		}
510 	}
511 
512 	if (!list_empty(&rq->sg_table_head)) {
513 		if (sgc->sge.prd.chain) {
514 			sgc->sge.prd.chain->ctl_len |=
515 				cpu_to_le32(sgc->sge.prd.sgl_max_cnt
516 					    - sgc->sge.prd.sge_cnt
517 					    - numchain);
518 		}
519 	}
520 
521 	return true;
522 }
523 
524 bool esas2r_build_sg_list_prd(struct esas2r_adapter *a,
525 			      struct esas2r_sg_context *sgc)
526 {
527 	struct esas2r_request *rq = sgc->first_req;
528 	u32 len = sgc->length;
529 	struct esas2r_target *t = a->targetdb + rq->target_id;
530 	u8 is_i_o = 0;
531 	u16 reqsize;
532 	struct atto_physical_region_description *curr_iblk_chn;
533 	u8 *cdb = (u8 *)&rq->vrq->scsi.cdb[0];
534 
535 	/*
536 	 * extract LBA from command so we can determine
537 	 * the I-Block boundary
538 	 */
539 
540 	if (rq->vrq->scsi.function == VDA_FUNC_SCSI
541 	    && t->target_state == TS_PRESENT
542 	    && !(t->flags & TF_PASS_THRU)) {
543 		u32 lbalo = 0;
544 
545 		switch (rq->vrq->scsi.cdb[0]) {
546 		case    READ_16:
547 		case    WRITE_16:
548 		{
549 			lbalo =
550 				MAKEDWORD(MAKEWORD(cdb[9],
551 						   cdb[8]),
552 					  MAKEWORD(cdb[7],
553 						   cdb[6]));
554 			is_i_o = 1;
555 			break;
556 		}
557 
558 		case    READ_12:
559 		case    WRITE_12:
560 		case    READ_10:
561 		case    WRITE_10:
562 		{
563 			lbalo =
564 				MAKEDWORD(MAKEWORD(cdb[5],
565 						   cdb[4]),
566 					  MAKEWORD(cdb[3],
567 						   cdb[2]));
568 			is_i_o = 1;
569 			break;
570 		}
571 
572 		case    READ_6:
573 		case    WRITE_6:
574 		{
575 			lbalo =
576 				MAKEDWORD(MAKEWORD(cdb[3],
577 						   cdb[2]),
578 					  MAKEWORD(cdb[1] & 0x1F,
579 						   0));
580 			is_i_o = 1;
581 			break;
582 		}
583 
584 		default:
585 			break;
586 		}
587 
588 		if (is_i_o) {
589 			u32 startlba;
590 
591 			rq->vrq->scsi.iblk_cnt_prd = 0;
592 
593 			/* Determine size of 1st I-block PRD list       */
594 			startlba = t->inter_block - (lbalo & (t->inter_block -
595 							      1));
596 			sgc->length = startlba * t->block_size;
597 
598 			/* Chk if the 1st iblk chain starts at base of Iblock */
599 			if ((lbalo & (t->inter_block - 1)) == 0)
600 				rq->flags |= RF_1ST_IBLK_BASE;
601 
602 			if (sgc->length > len)
603 				sgc->length = len;
604 		} else {
605 			sgc->length = len;
606 		}
607 	} else {
608 		sgc->length = len;
609 	}
610 
611 	/* get our starting chain address   */
612 
613 	curr_iblk_chn =
614 		(struct atto_physical_region_description *)sgc->sge.a64.curr;
615 
616 	sgc->sge.prd.sgl_max_cnt = sgl_page_size /
617 				   sizeof(struct
618 					  atto_physical_region_description);
619 
620 	/* create all of the I-block PRD lists          */
621 
622 	while (len) {
623 		sgc->sge.prd.sge_cnt = 0;
624 		sgc->sge.prd.chain = NULL;
625 		sgc->sge.prd.curr = curr_iblk_chn;
626 
627 		/* increment to next I-Block    */
628 
629 		len -= sgc->length;
630 
631 		/* go build the next I-Block PRD list   */
632 
633 		if (unlikely(!esas2r_build_prd_iblk(a, sgc)))
634 			return false;
635 
636 		curr_iblk_chn++;
637 
638 		if (is_i_o) {
639 			rq->vrq->scsi.iblk_cnt_prd++;
640 
641 			if (len > t->inter_byte)
642 				sgc->length = t->inter_byte;
643 			else
644 				sgc->length = len;
645 		}
646 	}
647 
648 	/* figure out the size used of the VDA request */
649 
650 	reqsize = ((u16)((u8 *)curr_iblk_chn - (u8 *)rq->vrq))
651 		  / sizeof(u32);
652 
653 	/*
654 	 * only update the request size if it is bigger than what is
655 	 * already there.  we can come in here twice for some management
656 	 * commands.
657 	 */
658 
659 	if (reqsize > rq->vda_req_sz)
660 		rq->vda_req_sz = reqsize;
661 
662 	return true;
663 }
664 
665 static void esas2r_handle_pending_reset(struct esas2r_adapter *a, u32 currtime)
666 {
667 	u32 delta = currtime - a->chip_init_time;
668 
669 	if (delta <= ESAS2R_CHPRST_WAIT_TIME) {
670 		/* Wait before accessing registers */
671 	} else if (delta >= ESAS2R_CHPRST_TIME) {
672 		/*
673 		 * The last reset failed so try again. Reset
674 		 * processing will give up after three tries.
675 		 */
676 		esas2r_local_reset_adapter(a);
677 	} else {
678 		/* We can now see if the firmware is ready */
679 		u32 doorbell;
680 
681 		doorbell = esas2r_read_register_dword(a, MU_DOORBELL_OUT);
682 		if (doorbell == 0xFFFFFFFF || !(doorbell & DRBL_FORCE_INT)) {
683 			esas2r_force_interrupt(a);
684 		} else {
685 			u32 ver = (doorbell & DRBL_FW_VER_MSK);
686 
687 			/* Driver supports API version 0 and 1 */
688 			esas2r_write_register_dword(a, MU_DOORBELL_OUT,
689 						    doorbell);
690 			if (ver == DRBL_FW_VER_0) {
691 				set_bit(AF_CHPRST_DETECTED, &a->flags);
692 				set_bit(AF_LEGACY_SGE_MODE, &a->flags);
693 
694 				a->max_vdareq_size = 128;
695 				a->build_sgl = esas2r_build_sg_list_sge;
696 			} else if (ver == DRBL_FW_VER_1) {
697 				set_bit(AF_CHPRST_DETECTED, &a->flags);
698 				clear_bit(AF_LEGACY_SGE_MODE, &a->flags);
699 
700 				a->max_vdareq_size = 1024;
701 				a->build_sgl = esas2r_build_sg_list_prd;
702 			} else {
703 				esas2r_local_reset_adapter(a);
704 			}
705 		}
706 	}
707 }
708 
709 
710 /* This function must be called once per timer tick */
711 void esas2r_timer_tick(struct esas2r_adapter *a)
712 {
713 	u32 currtime = jiffies_to_msecs(jiffies);
714 	u32 deltatime = currtime - a->last_tick_time;
715 
716 	a->last_tick_time = currtime;
717 
718 	/* count down the uptime */
719 	if (a->chip_uptime &&
720 	    !test_bit(AF_CHPRST_PENDING, &a->flags) &&
721 	    !test_bit(AF_DISC_PENDING, &a->flags)) {
722 		if (deltatime >= a->chip_uptime)
723 			a->chip_uptime = 0;
724 		else
725 			a->chip_uptime -= deltatime;
726 	}
727 
728 	if (test_bit(AF_CHPRST_PENDING, &a->flags)) {
729 		if (!test_bit(AF_CHPRST_NEEDED, &a->flags) &&
730 		    !test_bit(AF_CHPRST_DETECTED, &a->flags))
731 			esas2r_handle_pending_reset(a, currtime);
732 	} else {
733 		if (test_bit(AF_DISC_PENDING, &a->flags))
734 			esas2r_disc_check_complete(a);
735 		if (test_bit(AF_HEARTBEAT_ENB, &a->flags)) {
736 			if (test_bit(AF_HEARTBEAT, &a->flags)) {
737 				if ((currtime - a->heartbeat_time) >=
738 				    ESAS2R_HEARTBEAT_TIME) {
739 					clear_bit(AF_HEARTBEAT, &a->flags);
740 					esas2r_hdebug("heartbeat failed");
741 					esas2r_log(ESAS2R_LOG_CRIT,
742 						   "heartbeat failed");
743 					esas2r_bugon();
744 					esas2r_local_reset_adapter(a);
745 				}
746 			} else {
747 				set_bit(AF_HEARTBEAT, &a->flags);
748 				a->heartbeat_time = currtime;
749 				esas2r_force_interrupt(a);
750 			}
751 		}
752 	}
753 
754 	if (atomic_read(&a->disable_cnt) == 0)
755 		esas2r_do_deferred_processes(a);
756 }
757 
758 /*
759  * Send the specified task management function to the target and LUN
760  * specified in rqaux.  in addition, immediately abort any commands that
761  * are queued but not sent to the device according to the rules specified
762  * by the task management function.
763  */
764 bool esas2r_send_task_mgmt(struct esas2r_adapter *a,
765 			   struct esas2r_request *rqaux, u8 task_mgt_func)
766 {
767 	u16 targetid = rqaux->target_id;
768 	u8 lun = (u8)le32_to_cpu(rqaux->vrq->scsi.flags);
769 	bool ret = false;
770 	struct esas2r_request *rq;
771 	struct list_head *next, *element;
772 	unsigned long flags;
773 
774 	LIST_HEAD(comp_list);
775 
776 	esas2r_trace_enter();
777 	esas2r_trace("rqaux:%p", rqaux);
778 	esas2r_trace("task_mgt_func:%x", task_mgt_func);
779 	spin_lock_irqsave(&a->queue_lock, flags);
780 
781 	/* search the defer queue looking for requests for the device */
782 	list_for_each_safe(element, next, &a->defer_list) {
783 		rq = list_entry(element, struct esas2r_request, req_list);
784 
785 		if (rq->vrq->scsi.function == VDA_FUNC_SCSI
786 		    && rq->target_id == targetid
787 		    && (((u8)le32_to_cpu(rq->vrq->scsi.flags)) == lun
788 			|| task_mgt_func == 0x20)) { /* target reset */
789 			/* Found a request affected by the task management */
790 			if (rq->req_stat == RS_PENDING) {
791 				/*
792 				 * The request is pending or waiting.  We can
793 				 * safelycomplete the request now.
794 				 */
795 				if (esas2r_ioreq_aborted(a, rq, RS_ABORTED))
796 					list_add_tail(&rq->comp_list,
797 						      &comp_list);
798 			}
799 		}
800 	}
801 
802 	/* Send the task management request to the firmware */
803 	rqaux->sense_len = 0;
804 	rqaux->vrq->scsi.length = 0;
805 	rqaux->target_id = targetid;
806 	rqaux->vrq->scsi.flags |= cpu_to_le32(lun);
807 	memset(rqaux->vrq->scsi.cdb, 0, sizeof(rqaux->vrq->scsi.cdb));
808 	rqaux->vrq->scsi.flags |=
809 		cpu_to_le16(task_mgt_func * LOBIT(FCP_CMND_TM_MASK));
810 
811 	if (test_bit(AF_FLASHING, &a->flags)) {
812 		/* Assume success.  if there are active requests, return busy */
813 		rqaux->req_stat = RS_SUCCESS;
814 
815 		list_for_each_safe(element, next, &a->active_list) {
816 			rq = list_entry(element, struct esas2r_request,
817 					req_list);
818 			if (rq->vrq->scsi.function == VDA_FUNC_SCSI
819 			    && rq->target_id == targetid
820 			    && (((u8)le32_to_cpu(rq->vrq->scsi.flags)) == lun
821 				|| task_mgt_func == 0x20))  /* target reset */
822 				rqaux->req_stat = RS_BUSY;
823 		}
824 
825 		ret = true;
826 	}
827 
828 	spin_unlock_irqrestore(&a->queue_lock, flags);
829 
830 	if (!test_bit(AF_FLASHING, &a->flags))
831 		esas2r_start_request(a, rqaux);
832 
833 	esas2r_comp_list_drain(a, &comp_list);
834 
835 	if (atomic_read(&a->disable_cnt) == 0)
836 		esas2r_do_deferred_processes(a);
837 
838 	esas2r_trace_exit();
839 
840 	return ret;
841 }
842 
843 void esas2r_reset_bus(struct esas2r_adapter *a)
844 {
845 	esas2r_log(ESAS2R_LOG_INFO, "performing a bus reset");
846 
847 	if (!test_bit(AF_DEGRADED_MODE, &a->flags) &&
848 	    !test_bit(AF_CHPRST_PENDING, &a->flags) &&
849 	    !test_bit(AF_DISC_PENDING, &a->flags)) {
850 		set_bit(AF_BUSRST_NEEDED, &a->flags);
851 		set_bit(AF_BUSRST_PENDING, &a->flags);
852 		set_bit(AF_OS_RESET, &a->flags);
853 
854 		esas2r_schedule_tasklet(a);
855 	}
856 }
857 
858 bool esas2r_ioreq_aborted(struct esas2r_adapter *a, struct esas2r_request *rq,
859 			  u8 status)
860 {
861 	esas2r_trace_enter();
862 	esas2r_trace("rq:%p", rq);
863 	list_del_init(&rq->req_list);
864 	if (rq->timeout > RQ_MAX_TIMEOUT) {
865 		/*
866 		 * The request timed out, but we could not abort it because a
867 		 * chip reset occurred.  Return busy status.
868 		 */
869 		rq->req_stat = RS_BUSY;
870 		esas2r_trace_exit();
871 		return true;
872 	}
873 
874 	rq->req_stat = status;
875 	esas2r_trace_exit();
876 	return true;
877 }
878