xref: /openbmc/linux/drivers/scsi/qla2xxx/qla_iocb.c (revision 22246614)
1 /*
2  * QLogic Fibre Channel HBA Driver
3  * Copyright (c)  2003-2008 QLogic Corporation
4  *
5  * See LICENSE.qla2xxx for copyright and licensing details.
6  */
7 #include "qla_def.h"
8 
9 #include <linux/blkdev.h>
10 #include <linux/delay.h>
11 
12 #include <scsi/scsi_tcq.h>
13 
14 static request_t *qla2x00_req_pkt(scsi_qla_host_t *ha);
15 static void qla2x00_isp_cmd(scsi_qla_host_t *ha);
16 
17 /**
18  * qla2x00_get_cmd_direction() - Determine control_flag data direction.
19  * @cmd: SCSI command
20  *
21  * Returns the proper CF_* direction based on CDB.
22  */
23 static inline uint16_t
24 qla2x00_get_cmd_direction(struct scsi_cmnd *cmd)
25 {
26 	uint16_t cflags;
27 
28 	cflags = 0;
29 
30 	/* Set transfer direction */
31 	if (cmd->sc_data_direction == DMA_TO_DEVICE)
32 		cflags = CF_WRITE;
33 	else if (cmd->sc_data_direction == DMA_FROM_DEVICE)
34 		cflags = CF_READ;
35 	return (cflags);
36 }
37 
38 /**
39  * qla2x00_calc_iocbs_32() - Determine number of Command Type 2 and
40  * Continuation Type 0 IOCBs to allocate.
41  *
42  * @dsds: number of data segment decriptors needed
43  *
44  * Returns the number of IOCB entries needed to store @dsds.
45  */
46 uint16_t
47 qla2x00_calc_iocbs_32(uint16_t dsds)
48 {
49 	uint16_t iocbs;
50 
51 	iocbs = 1;
52 	if (dsds > 3) {
53 		iocbs += (dsds - 3) / 7;
54 		if ((dsds - 3) % 7)
55 			iocbs++;
56 	}
57 	return (iocbs);
58 }
59 
60 /**
61  * qla2x00_calc_iocbs_64() - Determine number of Command Type 3 and
62  * Continuation Type 1 IOCBs to allocate.
63  *
64  * @dsds: number of data segment decriptors needed
65  *
66  * Returns the number of IOCB entries needed to store @dsds.
67  */
68 uint16_t
69 qla2x00_calc_iocbs_64(uint16_t dsds)
70 {
71 	uint16_t iocbs;
72 
73 	iocbs = 1;
74 	if (dsds > 2) {
75 		iocbs += (dsds - 2) / 5;
76 		if ((dsds - 2) % 5)
77 			iocbs++;
78 	}
79 	return (iocbs);
80 }
81 
82 /**
83  * qla2x00_prep_cont_type0_iocb() - Initialize a Continuation Type 0 IOCB.
84  * @ha: HA context
85  *
86  * Returns a pointer to the Continuation Type 0 IOCB packet.
87  */
88 static inline cont_entry_t *
89 qla2x00_prep_cont_type0_iocb(scsi_qla_host_t *ha)
90 {
91 	cont_entry_t *cont_pkt;
92 
93 	/* Adjust ring index. */
94 	ha->req_ring_index++;
95 	if (ha->req_ring_index == ha->request_q_length) {
96 		ha->req_ring_index = 0;
97 		ha->request_ring_ptr = ha->request_ring;
98 	} else {
99 		ha->request_ring_ptr++;
100 	}
101 
102 	cont_pkt = (cont_entry_t *)ha->request_ring_ptr;
103 
104 	/* Load packet defaults. */
105 	*((uint32_t *)(&cont_pkt->entry_type)) =
106 	    __constant_cpu_to_le32(CONTINUE_TYPE);
107 
108 	return (cont_pkt);
109 }
110 
111 /**
112  * qla2x00_prep_cont_type1_iocb() - Initialize a Continuation Type 1 IOCB.
113  * @ha: HA context
114  *
115  * Returns a pointer to the continuation type 1 IOCB packet.
116  */
117 static inline cont_a64_entry_t *
118 qla2x00_prep_cont_type1_iocb(scsi_qla_host_t *ha)
119 {
120 	cont_a64_entry_t *cont_pkt;
121 
122 	/* Adjust ring index. */
123 	ha->req_ring_index++;
124 	if (ha->req_ring_index == ha->request_q_length) {
125 		ha->req_ring_index = 0;
126 		ha->request_ring_ptr = ha->request_ring;
127 	} else {
128 		ha->request_ring_ptr++;
129 	}
130 
131 	cont_pkt = (cont_a64_entry_t *)ha->request_ring_ptr;
132 
133 	/* Load packet defaults. */
134 	*((uint32_t *)(&cont_pkt->entry_type)) =
135 	    __constant_cpu_to_le32(CONTINUE_A64_TYPE);
136 
137 	return (cont_pkt);
138 }
139 
140 /**
141  * qla2x00_build_scsi_iocbs_32() - Build IOCB command utilizing 32bit
142  * capable IOCB types.
143  *
144  * @sp: SRB command to process
145  * @cmd_pkt: Command type 2 IOCB
146  * @tot_dsds: Total number of segments to transfer
147  */
148 void qla2x00_build_scsi_iocbs_32(srb_t *sp, cmd_entry_t *cmd_pkt,
149     uint16_t tot_dsds)
150 {
151 	uint16_t	avail_dsds;
152 	uint32_t	*cur_dsd;
153 	scsi_qla_host_t	*ha;
154 	struct scsi_cmnd *cmd;
155 	struct scatterlist *sg;
156 	int i;
157 
158 	cmd = sp->cmd;
159 
160 	/* Update entry type to indicate Command Type 2 IOCB */
161 	*((uint32_t *)(&cmd_pkt->entry_type)) =
162 	    __constant_cpu_to_le32(COMMAND_TYPE);
163 
164 	/* No data transfer */
165 	if (!scsi_bufflen(cmd) || cmd->sc_data_direction == DMA_NONE) {
166 		cmd_pkt->byte_count = __constant_cpu_to_le32(0);
167 		return;
168 	}
169 
170 	ha = sp->ha;
171 
172 	cmd_pkt->control_flags |= cpu_to_le16(qla2x00_get_cmd_direction(cmd));
173 
174 	/* Three DSDs are available in the Command Type 2 IOCB */
175 	avail_dsds = 3;
176 	cur_dsd = (uint32_t *)&cmd_pkt->dseg_0_address;
177 
178 	/* Load data segments */
179 	scsi_for_each_sg(cmd, sg, tot_dsds, i) {
180 		cont_entry_t *cont_pkt;
181 
182 		/* Allocate additional continuation packets? */
183 		if (avail_dsds == 0) {
184 			/*
185 			 * Seven DSDs are available in the Continuation
186 			 * Type 0 IOCB.
187 			 */
188 			cont_pkt = qla2x00_prep_cont_type0_iocb(ha);
189 			cur_dsd = (uint32_t *)&cont_pkt->dseg_0_address;
190 			avail_dsds = 7;
191 		}
192 
193 		*cur_dsd++ = cpu_to_le32(sg_dma_address(sg));
194 		*cur_dsd++ = cpu_to_le32(sg_dma_len(sg));
195 		avail_dsds--;
196 	}
197 }
198 
199 /**
200  * qla2x00_build_scsi_iocbs_64() - Build IOCB command utilizing 64bit
201  * capable IOCB types.
202  *
203  * @sp: SRB command to process
204  * @cmd_pkt: Command type 3 IOCB
205  * @tot_dsds: Total number of segments to transfer
206  */
207 void qla2x00_build_scsi_iocbs_64(srb_t *sp, cmd_entry_t *cmd_pkt,
208     uint16_t tot_dsds)
209 {
210 	uint16_t	avail_dsds;
211 	uint32_t	*cur_dsd;
212 	scsi_qla_host_t	*ha;
213 	struct scsi_cmnd *cmd;
214 	struct scatterlist *sg;
215 	int i;
216 
217 	cmd = sp->cmd;
218 
219 	/* Update entry type to indicate Command Type 3 IOCB */
220 	*((uint32_t *)(&cmd_pkt->entry_type)) =
221 	    __constant_cpu_to_le32(COMMAND_A64_TYPE);
222 
223 	/* No data transfer */
224 	if (!scsi_bufflen(cmd) || cmd->sc_data_direction == DMA_NONE) {
225 		cmd_pkt->byte_count = __constant_cpu_to_le32(0);
226 		return;
227 	}
228 
229 	ha = sp->ha;
230 
231 	cmd_pkt->control_flags |= cpu_to_le16(qla2x00_get_cmd_direction(cmd));
232 
233 	/* Two DSDs are available in the Command Type 3 IOCB */
234 	avail_dsds = 2;
235 	cur_dsd = (uint32_t *)&cmd_pkt->dseg_0_address;
236 
237 	/* Load data segments */
238 	scsi_for_each_sg(cmd, sg, tot_dsds, i) {
239 		dma_addr_t	sle_dma;
240 		cont_a64_entry_t *cont_pkt;
241 
242 		/* Allocate additional continuation packets? */
243 		if (avail_dsds == 0) {
244 			/*
245 			 * Five DSDs are available in the Continuation
246 			 * Type 1 IOCB.
247 			 */
248 			cont_pkt = qla2x00_prep_cont_type1_iocb(ha);
249 			cur_dsd = (uint32_t *)cont_pkt->dseg_0_address;
250 			avail_dsds = 5;
251 		}
252 
253 		sle_dma = sg_dma_address(sg);
254 		*cur_dsd++ = cpu_to_le32(LSD(sle_dma));
255 		*cur_dsd++ = cpu_to_le32(MSD(sle_dma));
256 		*cur_dsd++ = cpu_to_le32(sg_dma_len(sg));
257 		avail_dsds--;
258 	}
259 }
260 
261 /**
262  * qla2x00_start_scsi() - Send a SCSI command to the ISP
263  * @sp: command to send to the ISP
264  *
265  * Returns non-zero if a failure occured, else zero.
266  */
267 int
268 qla2x00_start_scsi(srb_t *sp)
269 {
270 	int		ret, nseg;
271 	unsigned long   flags;
272 	scsi_qla_host_t	*ha;
273 	struct scsi_cmnd *cmd;
274 	uint32_t	*clr_ptr;
275 	uint32_t        index;
276 	uint32_t	handle;
277 	cmd_entry_t	*cmd_pkt;
278 	uint16_t	cnt;
279 	uint16_t	req_cnt;
280 	uint16_t	tot_dsds;
281 	struct device_reg_2xxx __iomem *reg;
282 
283 	/* Setup device pointers. */
284 	ret = 0;
285 	ha = sp->ha;
286 	reg = &ha->iobase->isp;
287 	cmd = sp->cmd;
288 	/* So we know we haven't pci_map'ed anything yet */
289 	tot_dsds = 0;
290 
291 	/* Send marker if required */
292 	if (ha->marker_needed != 0) {
293 		if (qla2x00_marker(ha, 0, 0, MK_SYNC_ALL) != QLA_SUCCESS) {
294 			return (QLA_FUNCTION_FAILED);
295 		}
296 		ha->marker_needed = 0;
297 	}
298 
299 	/* Acquire ring specific lock */
300 	spin_lock_irqsave(&ha->hardware_lock, flags);
301 
302 	/* Check for room in outstanding command list. */
303 	handle = ha->current_outstanding_cmd;
304 	for (index = 1; index < MAX_OUTSTANDING_COMMANDS; index++) {
305 		handle++;
306 		if (handle == MAX_OUTSTANDING_COMMANDS)
307 			handle = 1;
308 		if (!ha->outstanding_cmds[handle])
309 			break;
310 	}
311 	if (index == MAX_OUTSTANDING_COMMANDS)
312 		goto queuing_error;
313 
314 	/* Map the sg table so we have an accurate count of sg entries needed */
315 	if (scsi_sg_count(cmd)) {
316 		nseg = dma_map_sg(&ha->pdev->dev, scsi_sglist(cmd),
317 		    scsi_sg_count(cmd), cmd->sc_data_direction);
318 		if (unlikely(!nseg))
319 			goto queuing_error;
320 	} else
321 		nseg = 0;
322 
323 	tot_dsds = nseg;
324 
325 	/* Calculate the number of request entries needed. */
326 	req_cnt = ha->isp_ops->calc_req_entries(tot_dsds);
327 	if (ha->req_q_cnt < (req_cnt + 2)) {
328 		cnt = RD_REG_WORD_RELAXED(ISP_REQ_Q_OUT(ha, reg));
329 		if (ha->req_ring_index < cnt)
330 			ha->req_q_cnt = cnt - ha->req_ring_index;
331 		else
332 			ha->req_q_cnt = ha->request_q_length -
333 			    (ha->req_ring_index - cnt);
334 	}
335 	if (ha->req_q_cnt < (req_cnt + 2))
336 		goto queuing_error;
337 
338 	/* Build command packet */
339 	ha->current_outstanding_cmd = handle;
340 	ha->outstanding_cmds[handle] = sp;
341 	sp->ha = ha;
342 	sp->cmd->host_scribble = (unsigned char *)(unsigned long)handle;
343 	ha->req_q_cnt -= req_cnt;
344 
345 	cmd_pkt = (cmd_entry_t *)ha->request_ring_ptr;
346 	cmd_pkt->handle = handle;
347 	/* Zero out remaining portion of packet. */
348 	clr_ptr = (uint32_t *)cmd_pkt + 2;
349 	memset(clr_ptr, 0, REQUEST_ENTRY_SIZE - 8);
350 	cmd_pkt->dseg_count = cpu_to_le16(tot_dsds);
351 
352 	/* Set target ID and LUN number*/
353 	SET_TARGET_ID(ha, cmd_pkt->target, sp->fcport->loop_id);
354 	cmd_pkt->lun = cpu_to_le16(sp->cmd->device->lun);
355 
356 	/* Update tagged queuing modifier */
357 	cmd_pkt->control_flags = __constant_cpu_to_le16(CF_SIMPLE_TAG);
358 
359 	/* Load SCSI command packet. */
360 	memcpy(cmd_pkt->scsi_cdb, cmd->cmnd, cmd->cmd_len);
361 	cmd_pkt->byte_count = cpu_to_le32((uint32_t)scsi_bufflen(cmd));
362 
363 	/* Build IOCB segments */
364 	ha->isp_ops->build_iocbs(sp, cmd_pkt, tot_dsds);
365 
366 	/* Set total data segment count. */
367 	cmd_pkt->entry_count = (uint8_t)req_cnt;
368 	wmb();
369 
370 	/* Adjust ring index. */
371 	ha->req_ring_index++;
372 	if (ha->req_ring_index == ha->request_q_length) {
373 		ha->req_ring_index = 0;
374 		ha->request_ring_ptr = ha->request_ring;
375 	} else
376 		ha->request_ring_ptr++;
377 
378 	sp->flags |= SRB_DMA_VALID;
379 
380 	/* Set chip new ring index. */
381 	WRT_REG_WORD(ISP_REQ_Q_IN(ha, reg), ha->req_ring_index);
382 	RD_REG_WORD_RELAXED(ISP_REQ_Q_IN(ha, reg));	/* PCI Posting. */
383 
384 	/* Manage unprocessed RIO/ZIO commands in response queue. */
385 	if (ha->flags.process_response_queue &&
386 	    ha->response_ring_ptr->signature != RESPONSE_PROCESSED)
387 		qla2x00_process_response_queue(ha);
388 
389 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
390 	return (QLA_SUCCESS);
391 
392 queuing_error:
393 	if (tot_dsds)
394 		scsi_dma_unmap(cmd);
395 
396 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
397 
398 	return (QLA_FUNCTION_FAILED);
399 }
400 
401 /**
402  * qla2x00_marker() - Send a marker IOCB to the firmware.
403  * @ha: HA context
404  * @loop_id: loop ID
405  * @lun: LUN
406  * @type: marker modifier
407  *
408  * Can be called from both normal and interrupt context.
409  *
410  * Returns non-zero if a failure occured, else zero.
411  */
412 int
413 __qla2x00_marker(scsi_qla_host_t *ha, uint16_t loop_id, uint16_t lun,
414     uint8_t type)
415 {
416 	mrk_entry_t *mrk;
417 	struct mrk_entry_24xx *mrk24;
418 	scsi_qla_host_t *pha = to_qla_parent(ha);
419 
420 	mrk24 = NULL;
421 	mrk = (mrk_entry_t *)qla2x00_req_pkt(pha);
422 	if (mrk == NULL) {
423 		DEBUG2_3(printk("%s(%ld): failed to allocate Marker IOCB.\n",
424 		    __func__, ha->host_no));
425 
426 		return (QLA_FUNCTION_FAILED);
427 	}
428 
429 	mrk->entry_type = MARKER_TYPE;
430 	mrk->modifier = type;
431 	if (type != MK_SYNC_ALL) {
432 		if (IS_FWI2_CAPABLE(ha)) {
433 			mrk24 = (struct mrk_entry_24xx *) mrk;
434 			mrk24->nport_handle = cpu_to_le16(loop_id);
435 			mrk24->lun[1] = LSB(lun);
436 			mrk24->lun[2] = MSB(lun);
437 			host_to_fcp_swap(mrk24->lun, sizeof(mrk24->lun));
438 			mrk24->vp_index = ha->vp_idx;
439 		} else {
440 			SET_TARGET_ID(ha, mrk->target, loop_id);
441 			mrk->lun = cpu_to_le16(lun);
442 		}
443 	}
444 	wmb();
445 
446 	qla2x00_isp_cmd(pha);
447 
448 	return (QLA_SUCCESS);
449 }
450 
451 int
452 qla2x00_marker(scsi_qla_host_t *ha, uint16_t loop_id, uint16_t lun,
453     uint8_t type)
454 {
455 	int ret;
456 	unsigned long flags = 0;
457 
458 	spin_lock_irqsave(&ha->hardware_lock, flags);
459 	ret = __qla2x00_marker(ha, loop_id, lun, type);
460 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
461 
462 	return (ret);
463 }
464 
465 /**
466  * qla2x00_req_pkt() - Retrieve a request packet from the request ring.
467  * @ha: HA context
468  *
469  * Note: The caller must hold the hardware lock before calling this routine.
470  *
471  * Returns NULL if function failed, else, a pointer to the request packet.
472  */
473 static request_t *
474 qla2x00_req_pkt(scsi_qla_host_t *ha)
475 {
476 	device_reg_t __iomem *reg = ha->iobase;
477 	request_t	*pkt = NULL;
478 	uint16_t	cnt;
479 	uint32_t	*dword_ptr;
480 	uint32_t	timer;
481 	uint16_t	req_cnt = 1;
482 
483 	/* Wait 1 second for slot. */
484 	for (timer = HZ; timer; timer--) {
485 		if ((req_cnt + 2) >= ha->req_q_cnt) {
486 			/* Calculate number of free request entries. */
487 			if (IS_FWI2_CAPABLE(ha))
488 				cnt = (uint16_t)RD_REG_DWORD(
489 				    &reg->isp24.req_q_out);
490 			else
491 				cnt = qla2x00_debounce_register(
492 				    ISP_REQ_Q_OUT(ha, &reg->isp));
493 			if  (ha->req_ring_index < cnt)
494 				ha->req_q_cnt = cnt - ha->req_ring_index;
495 			else
496 				ha->req_q_cnt = ha->request_q_length -
497 				    (ha->req_ring_index - cnt);
498 		}
499 		/* If room for request in request ring. */
500 		if ((req_cnt + 2) < ha->req_q_cnt) {
501 			ha->req_q_cnt--;
502 			pkt = ha->request_ring_ptr;
503 
504 			/* Zero out packet. */
505 			dword_ptr = (uint32_t *)pkt;
506 			for (cnt = 0; cnt < REQUEST_ENTRY_SIZE / 4; cnt++)
507 				*dword_ptr++ = 0;
508 
509 			/* Set system defined field. */
510 			pkt->sys_define = (uint8_t)ha->req_ring_index;
511 
512 			/* Set entry count. */
513 			pkt->entry_count = 1;
514 
515 			break;
516 		}
517 
518 		/* Release ring specific lock */
519 		spin_unlock(&ha->hardware_lock);
520 
521 		udelay(2);   /* 2 us */
522 
523 		/* Check for pending interrupts. */
524 		/* During init we issue marker directly */
525 		if (!ha->marker_needed && !ha->flags.init_done)
526 			qla2x00_poll(ha);
527 
528 		spin_lock_irq(&ha->hardware_lock);
529 	}
530 	if (!pkt) {
531 		DEBUG2_3(printk("%s(): **** FAILED ****\n", __func__));
532 	}
533 
534 	return (pkt);
535 }
536 
537 /**
538  * qla2x00_isp_cmd() - Modify the request ring pointer.
539  * @ha: HA context
540  *
541  * Note: The caller must hold the hardware lock before calling this routine.
542  */
543 static void
544 qla2x00_isp_cmd(scsi_qla_host_t *ha)
545 {
546 	device_reg_t __iomem *reg = ha->iobase;
547 
548 	DEBUG5(printk("%s(): IOCB data:\n", __func__));
549 	DEBUG5(qla2x00_dump_buffer(
550 	    (uint8_t *)ha->request_ring_ptr, REQUEST_ENTRY_SIZE));
551 
552 	/* Adjust ring index. */
553 	ha->req_ring_index++;
554 	if (ha->req_ring_index == ha->request_q_length) {
555 		ha->req_ring_index = 0;
556 		ha->request_ring_ptr = ha->request_ring;
557 	} else
558 		ha->request_ring_ptr++;
559 
560 	/* Set chip new ring index. */
561 	if (IS_FWI2_CAPABLE(ha)) {
562 		WRT_REG_DWORD(&reg->isp24.req_q_in, ha->req_ring_index);
563 		RD_REG_DWORD_RELAXED(&reg->isp24.req_q_in);
564 	} else {
565 		WRT_REG_WORD(ISP_REQ_Q_IN(ha, &reg->isp), ha->req_ring_index);
566 		RD_REG_WORD_RELAXED(ISP_REQ_Q_IN(ha, &reg->isp));
567 	}
568 
569 }
570 
571 /**
572  * qla24xx_calc_iocbs() - Determine number of Command Type 3 and
573  * Continuation Type 1 IOCBs to allocate.
574  *
575  * @dsds: number of data segment decriptors needed
576  *
577  * Returns the number of IOCB entries needed to store @dsds.
578  */
579 static inline uint16_t
580 qla24xx_calc_iocbs(uint16_t dsds)
581 {
582 	uint16_t iocbs;
583 
584 	iocbs = 1;
585 	if (dsds > 1) {
586 		iocbs += (dsds - 1) / 5;
587 		if ((dsds - 1) % 5)
588 			iocbs++;
589 	}
590 	return iocbs;
591 }
592 
593 /**
594  * qla24xx_build_scsi_iocbs() - Build IOCB command utilizing Command Type 7
595  * IOCB types.
596  *
597  * @sp: SRB command to process
598  * @cmd_pkt: Command type 3 IOCB
599  * @tot_dsds: Total number of segments to transfer
600  */
601 static inline void
602 qla24xx_build_scsi_iocbs(srb_t *sp, struct cmd_type_7 *cmd_pkt,
603     uint16_t tot_dsds)
604 {
605 	uint16_t	avail_dsds;
606 	uint32_t	*cur_dsd;
607 	scsi_qla_host_t	*ha;
608 	struct scsi_cmnd *cmd;
609 	struct scatterlist *sg;
610 	int i;
611 
612 	cmd = sp->cmd;
613 
614 	/* Update entry type to indicate Command Type 3 IOCB */
615 	*((uint32_t *)(&cmd_pkt->entry_type)) =
616 	    __constant_cpu_to_le32(COMMAND_TYPE_7);
617 
618 	/* No data transfer */
619 	if (!scsi_bufflen(cmd) || cmd->sc_data_direction == DMA_NONE) {
620 		cmd_pkt->byte_count = __constant_cpu_to_le32(0);
621 		return;
622 	}
623 
624 	ha = sp->ha;
625 
626 	/* Set transfer direction */
627 	if (cmd->sc_data_direction == DMA_TO_DEVICE)
628 		cmd_pkt->task_mgmt_flags =
629 		    __constant_cpu_to_le16(TMF_WRITE_DATA);
630 	else if (cmd->sc_data_direction == DMA_FROM_DEVICE)
631 		cmd_pkt->task_mgmt_flags =
632 		    __constant_cpu_to_le16(TMF_READ_DATA);
633 
634 	/* One DSD is available in the Command Type 3 IOCB */
635 	avail_dsds = 1;
636 	cur_dsd = (uint32_t *)&cmd_pkt->dseg_0_address;
637 
638 	/* Load data segments */
639 
640 	scsi_for_each_sg(cmd, sg, tot_dsds, i) {
641 		dma_addr_t	sle_dma;
642 		cont_a64_entry_t *cont_pkt;
643 
644 		/* Allocate additional continuation packets? */
645 		if (avail_dsds == 0) {
646 			/*
647 			 * Five DSDs are available in the Continuation
648 			 * Type 1 IOCB.
649 			 */
650 			cont_pkt = qla2x00_prep_cont_type1_iocb(ha);
651 			cur_dsd = (uint32_t *)cont_pkt->dseg_0_address;
652 			avail_dsds = 5;
653 		}
654 
655 		sle_dma = sg_dma_address(sg);
656 		*cur_dsd++ = cpu_to_le32(LSD(sle_dma));
657 		*cur_dsd++ = cpu_to_le32(MSD(sle_dma));
658 		*cur_dsd++ = cpu_to_le32(sg_dma_len(sg));
659 		avail_dsds--;
660 	}
661 }
662 
663 
664 /**
665  * qla24xx_start_scsi() - Send a SCSI command to the ISP
666  * @sp: command to send to the ISP
667  *
668  * Returns non-zero if a failure occured, else zero.
669  */
670 int
671 qla24xx_start_scsi(srb_t *sp)
672 {
673 	int		ret, nseg;
674 	unsigned long   flags;
675 	scsi_qla_host_t	*ha;
676 	struct scsi_cmnd *cmd;
677 	uint32_t	*clr_ptr;
678 	uint32_t        index;
679 	uint32_t	handle;
680 	struct cmd_type_7 *cmd_pkt;
681 	uint16_t	cnt;
682 	uint16_t	req_cnt;
683 	uint16_t	tot_dsds;
684 	struct device_reg_24xx __iomem *reg;
685 
686 	/* Setup device pointers. */
687 	ret = 0;
688 	ha = sp->ha;
689 	reg = &ha->iobase->isp24;
690 	cmd = sp->cmd;
691 	/* So we know we haven't pci_map'ed anything yet */
692 	tot_dsds = 0;
693 
694 	/* Send marker if required */
695 	if (ha->marker_needed != 0) {
696 		if (qla2x00_marker(ha, 0, 0, MK_SYNC_ALL) != QLA_SUCCESS) {
697 			return QLA_FUNCTION_FAILED;
698 		}
699 		ha->marker_needed = 0;
700 	}
701 
702 	/* Acquire ring specific lock */
703 	spin_lock_irqsave(&ha->hardware_lock, flags);
704 
705 	/* Check for room in outstanding command list. */
706 	handle = ha->current_outstanding_cmd;
707 	for (index = 1; index < MAX_OUTSTANDING_COMMANDS; index++) {
708 		handle++;
709 		if (handle == MAX_OUTSTANDING_COMMANDS)
710 			handle = 1;
711 		if (!ha->outstanding_cmds[handle])
712 			break;
713 	}
714 	if (index == MAX_OUTSTANDING_COMMANDS)
715 		goto queuing_error;
716 
717 	/* Map the sg table so we have an accurate count of sg entries needed */
718 	if (scsi_sg_count(cmd)) {
719 		nseg = dma_map_sg(&ha->pdev->dev, scsi_sglist(cmd),
720 		    scsi_sg_count(cmd), cmd->sc_data_direction);
721 		if (unlikely(!nseg))
722 			goto queuing_error;
723 	} else
724 		nseg = 0;
725 
726 	tot_dsds = nseg;
727 
728 	req_cnt = qla24xx_calc_iocbs(tot_dsds);
729 	if (ha->req_q_cnt < (req_cnt + 2)) {
730 		cnt = (uint16_t)RD_REG_DWORD_RELAXED(&reg->req_q_out);
731 		if (ha->req_ring_index < cnt)
732 			ha->req_q_cnt = cnt - ha->req_ring_index;
733 		else
734 			ha->req_q_cnt = ha->request_q_length -
735 				(ha->req_ring_index - cnt);
736 	}
737 	if (ha->req_q_cnt < (req_cnt + 2))
738 		goto queuing_error;
739 
740 	/* Build command packet. */
741 	ha->current_outstanding_cmd = handle;
742 	ha->outstanding_cmds[handle] = sp;
743 	sp->ha = ha;
744 	sp->cmd->host_scribble = (unsigned char *)(unsigned long)handle;
745 	ha->req_q_cnt -= req_cnt;
746 
747 	cmd_pkt = (struct cmd_type_7 *)ha->request_ring_ptr;
748 	cmd_pkt->handle = handle;
749 
750 	/* Zero out remaining portion of packet. */
751 	/*    tagged queuing modifier -- default is TSK_SIMPLE (0). */
752 	clr_ptr = (uint32_t *)cmd_pkt + 2;
753 	memset(clr_ptr, 0, REQUEST_ENTRY_SIZE - 8);
754 	cmd_pkt->dseg_count = cpu_to_le16(tot_dsds);
755 
756 	/* Set NPORT-ID and LUN number*/
757 	cmd_pkt->nport_handle = cpu_to_le16(sp->fcport->loop_id);
758 	cmd_pkt->port_id[0] = sp->fcport->d_id.b.al_pa;
759 	cmd_pkt->port_id[1] = sp->fcport->d_id.b.area;
760 	cmd_pkt->port_id[2] = sp->fcport->d_id.b.domain;
761 	cmd_pkt->vp_index = sp->fcport->vp_idx;
762 
763 	int_to_scsilun(sp->cmd->device->lun, &cmd_pkt->lun);
764 	host_to_fcp_swap((uint8_t *)&cmd_pkt->lun, sizeof(cmd_pkt->lun));
765 
766 	/* Load SCSI command packet. */
767 	memcpy(cmd_pkt->fcp_cdb, cmd->cmnd, cmd->cmd_len);
768 	host_to_fcp_swap(cmd_pkt->fcp_cdb, sizeof(cmd_pkt->fcp_cdb));
769 
770 	cmd_pkt->byte_count = cpu_to_le32((uint32_t)scsi_bufflen(cmd));
771 
772 	/* Build IOCB segments */
773 	qla24xx_build_scsi_iocbs(sp, cmd_pkt, tot_dsds);
774 
775 	/* Set total data segment count. */
776 	cmd_pkt->entry_count = (uint8_t)req_cnt;
777 	wmb();
778 
779 	/* Adjust ring index. */
780 	ha->req_ring_index++;
781 	if (ha->req_ring_index == ha->request_q_length) {
782 		ha->req_ring_index = 0;
783 		ha->request_ring_ptr = ha->request_ring;
784 	} else
785 		ha->request_ring_ptr++;
786 
787 	sp->flags |= SRB_DMA_VALID;
788 
789 	/* Set chip new ring index. */
790 	WRT_REG_DWORD(&reg->req_q_in, ha->req_ring_index);
791 	RD_REG_DWORD_RELAXED(&reg->req_q_in);		/* PCI Posting. */
792 
793 	/* Manage unprocessed RIO/ZIO commands in response queue. */
794 	if (ha->flags.process_response_queue &&
795 	    ha->response_ring_ptr->signature != RESPONSE_PROCESSED)
796 		qla24xx_process_response_queue(ha);
797 
798 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
799 	return QLA_SUCCESS;
800 
801 queuing_error:
802 	if (tot_dsds)
803 		scsi_dma_unmap(cmd);
804 
805 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
806 
807 	return QLA_FUNCTION_FAILED;
808 }
809