xref: /linux/drivers/scsi/qla2xxx/qla_iocb.c (revision 2624f124b3b5d550ab2fbef7ee3bc0e1fed09722)
1 /******************************************************************************
2  *                  QLOGIC LINUX SOFTWARE
3  *
4  * QLogic ISP2x00 device driver for Linux 2.6.x
5  * Copyright (C) 2003-2005 QLogic Corporation
6  * (www.qlogic.com)
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms of the GNU General Public License as published by the
10  * Free Software Foundation; either version 2, or (at your option) any
11  * later version.
12  *
13  * This program is distributed in the hope that it will be useful, but
14  * WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * General Public License for more details.
17  *
18  ******************************************************************************/
19 
20 #include "qla_def.h"
21 
22 #include <linux/blkdev.h>
23 #include <linux/delay.h>
24 
25 #include <scsi/scsi_tcq.h>
26 
27 static inline uint16_t qla2x00_get_cmd_direction(struct scsi_cmnd *cmd);
28 static inline cont_entry_t *qla2x00_prep_cont_type0_iocb(scsi_qla_host_t *);
29 static inline cont_a64_entry_t *qla2x00_prep_cont_type1_iocb(scsi_qla_host_t *);
30 static request_t *qla2x00_req_pkt(scsi_qla_host_t *ha);
31 
32 /**
33  * qla2x00_get_cmd_direction() - Determine control_flag data direction.
34  * @cmd: SCSI command
35  *
36  * Returns the proper CF_* direction based on CDB.
37  */
38 static inline uint16_t
39 qla2x00_get_cmd_direction(struct scsi_cmnd *cmd)
40 {
41 	uint16_t cflags;
42 
43 	cflags = 0;
44 
45 	/* Set transfer direction */
46 	if (cmd->sc_data_direction == DMA_TO_DEVICE)
47 		cflags = CF_WRITE;
48 	else if (cmd->sc_data_direction == DMA_FROM_DEVICE)
49 		cflags = CF_READ;
50 	return (cflags);
51 }
52 
53 /**
54  * qla2x00_calc_iocbs_32() - Determine number of Command Type 2 and
55  * Continuation Type 0 IOCBs to allocate.
56  *
57  * @dsds: number of data segment decriptors needed
58  *
59  * Returns the number of IOCB entries needed to store @dsds.
60  */
61 uint16_t
62 qla2x00_calc_iocbs_32(uint16_t dsds)
63 {
64 	uint16_t iocbs;
65 
66 	iocbs = 1;
67 	if (dsds > 3) {
68 		iocbs += (dsds - 3) / 7;
69 		if ((dsds - 3) % 7)
70 			iocbs++;
71 	}
72 	return (iocbs);
73 }
74 
75 /**
76  * qla2x00_calc_iocbs_64() - Determine number of Command Type 3 and
77  * Continuation Type 1 IOCBs to allocate.
78  *
79  * @dsds: number of data segment decriptors needed
80  *
81  * Returns the number of IOCB entries needed to store @dsds.
82  */
83 uint16_t
84 qla2x00_calc_iocbs_64(uint16_t dsds)
85 {
86 	uint16_t iocbs;
87 
88 	iocbs = 1;
89 	if (dsds > 2) {
90 		iocbs += (dsds - 2) / 5;
91 		if ((dsds - 2) % 5)
92 			iocbs++;
93 	}
94 	return (iocbs);
95 }
96 
97 /**
98  * qla2x00_prep_cont_type0_iocb() - Initialize a Continuation Type 0 IOCB.
99  * @ha: HA context
100  *
101  * Returns a pointer to the Continuation Type 0 IOCB packet.
102  */
103 static inline cont_entry_t *
104 qla2x00_prep_cont_type0_iocb(scsi_qla_host_t *ha)
105 {
106 	cont_entry_t *cont_pkt;
107 
108 	/* Adjust ring index. */
109 	ha->req_ring_index++;
110 	if (ha->req_ring_index == ha->request_q_length) {
111 		ha->req_ring_index = 0;
112 		ha->request_ring_ptr = ha->request_ring;
113 	} else {
114 		ha->request_ring_ptr++;
115 	}
116 
117 	cont_pkt = (cont_entry_t *)ha->request_ring_ptr;
118 
119 	/* Load packet defaults. */
120 	*((uint32_t *)(&cont_pkt->entry_type)) =
121 	    __constant_cpu_to_le32(CONTINUE_TYPE);
122 
123 	return (cont_pkt);
124 }
125 
126 /**
127  * qla2x00_prep_cont_type1_iocb() - Initialize a Continuation Type 1 IOCB.
128  * @ha: HA context
129  *
130  * Returns a pointer to the continuation type 1 IOCB packet.
131  */
132 static inline cont_a64_entry_t *
133 qla2x00_prep_cont_type1_iocb(scsi_qla_host_t *ha)
134 {
135 	cont_a64_entry_t *cont_pkt;
136 
137 	/* Adjust ring index. */
138 	ha->req_ring_index++;
139 	if (ha->req_ring_index == ha->request_q_length) {
140 		ha->req_ring_index = 0;
141 		ha->request_ring_ptr = ha->request_ring;
142 	} else {
143 		ha->request_ring_ptr++;
144 	}
145 
146 	cont_pkt = (cont_a64_entry_t *)ha->request_ring_ptr;
147 
148 	/* Load packet defaults. */
149 	*((uint32_t *)(&cont_pkt->entry_type)) =
150 	    __constant_cpu_to_le32(CONTINUE_A64_TYPE);
151 
152 	return (cont_pkt);
153 }
154 
155 /**
156  * qla2x00_build_scsi_iocbs_32() - Build IOCB command utilizing 32bit
157  * capable IOCB types.
158  *
159  * @sp: SRB command to process
160  * @cmd_pkt: Command type 2 IOCB
161  * @tot_dsds: Total number of segments to transfer
162  */
163 void qla2x00_build_scsi_iocbs_32(srb_t *sp, cmd_entry_t *cmd_pkt,
164     uint16_t tot_dsds)
165 {
166 	uint16_t	avail_dsds;
167 	uint32_t	*cur_dsd;
168 	scsi_qla_host_t	*ha;
169 	struct scsi_cmnd *cmd;
170 
171 	cmd = sp->cmd;
172 
173 	/* Update entry type to indicate Command Type 2 IOCB */
174 	*((uint32_t *)(&cmd_pkt->entry_type)) =
175 	    __constant_cpu_to_le32(COMMAND_TYPE);
176 
177 	/* No data transfer */
178 	if (cmd->request_bufflen == 0 || cmd->sc_data_direction == DMA_NONE) {
179 		cmd_pkt->byte_count = __constant_cpu_to_le32(0);
180 		return;
181 	}
182 
183 	ha = sp->ha;
184 
185 	cmd_pkt->control_flags |= cpu_to_le16(qla2x00_get_cmd_direction(cmd));
186 
187 	/* Three DSDs are available in the Command Type 2 IOCB */
188 	avail_dsds = 3;
189 	cur_dsd = (uint32_t *)&cmd_pkt->dseg_0_address;
190 
191 	/* Load data segments */
192 	if (cmd->use_sg != 0) {
193 		struct	scatterlist *cur_seg;
194 		struct	scatterlist *end_seg;
195 
196 		cur_seg = (struct scatterlist *)cmd->request_buffer;
197 		end_seg = cur_seg + tot_dsds;
198 		while (cur_seg < end_seg) {
199 			cont_entry_t	*cont_pkt;
200 
201 			/* Allocate additional continuation packets? */
202 			if (avail_dsds == 0) {
203 				/*
204 				 * Seven DSDs are available in the Continuation
205 				 * Type 0 IOCB.
206 				 */
207 				cont_pkt = qla2x00_prep_cont_type0_iocb(ha);
208 				cur_dsd = (uint32_t *)&cont_pkt->dseg_0_address;
209 				avail_dsds = 7;
210 			}
211 
212 			*cur_dsd++ = cpu_to_le32(sg_dma_address(cur_seg));
213 			*cur_dsd++ = cpu_to_le32(sg_dma_len(cur_seg));
214 			avail_dsds--;
215 
216 			cur_seg++;
217 		}
218 	} else {
219 		*cur_dsd++ = cpu_to_le32(sp->dma_handle);
220 		*cur_dsd++ = cpu_to_le32(cmd->request_bufflen);
221 	}
222 }
223 
224 /**
225  * qla2x00_build_scsi_iocbs_64() - Build IOCB command utilizing 64bit
226  * capable IOCB types.
227  *
228  * @sp: SRB command to process
229  * @cmd_pkt: Command type 3 IOCB
230  * @tot_dsds: Total number of segments to transfer
231  */
232 void qla2x00_build_scsi_iocbs_64(srb_t *sp, cmd_entry_t *cmd_pkt,
233     uint16_t tot_dsds)
234 {
235 	uint16_t	avail_dsds;
236 	uint32_t	*cur_dsd;
237 	scsi_qla_host_t	*ha;
238 	struct scsi_cmnd *cmd;
239 
240 	cmd = sp->cmd;
241 
242 	/* Update entry type to indicate Command Type 3 IOCB */
243 	*((uint32_t *)(&cmd_pkt->entry_type)) =
244 	    __constant_cpu_to_le32(COMMAND_A64_TYPE);
245 
246 	/* No data transfer */
247 	if (cmd->request_bufflen == 0 || cmd->sc_data_direction == DMA_NONE) {
248 		cmd_pkt->byte_count = __constant_cpu_to_le32(0);
249 		return;
250 	}
251 
252 	ha = sp->ha;
253 
254 	cmd_pkt->control_flags |= cpu_to_le16(qla2x00_get_cmd_direction(cmd));
255 
256 	/* Two DSDs are available in the Command Type 3 IOCB */
257 	avail_dsds = 2;
258 	cur_dsd = (uint32_t *)&cmd_pkt->dseg_0_address;
259 
260 	/* Load data segments */
261 	if (cmd->use_sg != 0) {
262 		struct	scatterlist *cur_seg;
263 		struct	scatterlist *end_seg;
264 
265 		cur_seg = (struct scatterlist *)cmd->request_buffer;
266 		end_seg = cur_seg + tot_dsds;
267 		while (cur_seg < end_seg) {
268 			dma_addr_t	sle_dma;
269 			cont_a64_entry_t *cont_pkt;
270 
271 			/* Allocate additional continuation packets? */
272 			if (avail_dsds == 0) {
273 				/*
274 				 * Five DSDs are available in the Continuation
275 				 * Type 1 IOCB.
276 				 */
277 				cont_pkt = qla2x00_prep_cont_type1_iocb(ha);
278 				cur_dsd = (uint32_t *)cont_pkt->dseg_0_address;
279 				avail_dsds = 5;
280 			}
281 
282 			sle_dma = sg_dma_address(cur_seg);
283 			*cur_dsd++ = cpu_to_le32(LSD(sle_dma));
284 			*cur_dsd++ = cpu_to_le32(MSD(sle_dma));
285 			*cur_dsd++ = cpu_to_le32(sg_dma_len(cur_seg));
286 			avail_dsds--;
287 
288 			cur_seg++;
289 		}
290 	} else {
291 		*cur_dsd++ = cpu_to_le32(LSD(sp->dma_handle));
292 		*cur_dsd++ = cpu_to_le32(MSD(sp->dma_handle));
293 		*cur_dsd++ = cpu_to_le32(cmd->request_bufflen);
294 	}
295 }
296 
297 /**
298  * qla2x00_start_scsi() - Send a SCSI command to the ISP
299  * @sp: command to send to the ISP
300  *
301  * Returns non-zero if a failure occured, else zero.
302  */
303 int
304 qla2x00_start_scsi(srb_t *sp)
305 {
306 	int		ret;
307 	unsigned long   flags;
308 	scsi_qla_host_t	*ha;
309 	struct scsi_cmnd *cmd;
310 	uint32_t	*clr_ptr;
311 	uint32_t        index;
312 	uint32_t	handle;
313 	cmd_entry_t	*cmd_pkt;
314 	struct scatterlist *sg;
315 	uint16_t	cnt;
316 	uint16_t	req_cnt;
317 	uint16_t	tot_dsds;
318 	struct device_reg_2xxx __iomem *reg;
319 	char		tag[2];
320 
321 	/* Setup device pointers. */
322 	ret = 0;
323 	ha = sp->ha;
324 	reg = &ha->iobase->isp;
325 	cmd = sp->cmd;
326 	/* So we know we haven't pci_map'ed anything yet */
327 	tot_dsds = 0;
328 
329 	/* Send marker if required */
330 	if (ha->marker_needed != 0) {
331 		if (qla2x00_marker(ha, 0, 0, MK_SYNC_ALL) != QLA_SUCCESS) {
332 			return (QLA_FUNCTION_FAILED);
333 		}
334 		ha->marker_needed = 0;
335 	}
336 
337 	/* Acquire ring specific lock */
338 	spin_lock_irqsave(&ha->hardware_lock, flags);
339 
340 	/* Check for room in outstanding command list. */
341 	handle = ha->current_outstanding_cmd;
342 	for (index = 1; index < MAX_OUTSTANDING_COMMANDS; index++) {
343 		handle++;
344 		if (handle == MAX_OUTSTANDING_COMMANDS)
345 			handle = 1;
346 		if (ha->outstanding_cmds[handle] == 0)
347 			break;
348 	}
349 	if (index == MAX_OUTSTANDING_COMMANDS)
350 		goto queuing_error;
351 
352 	/* Map the sg table so we have an accurate count of sg entries needed */
353 	if (cmd->use_sg) {
354 		sg = (struct scatterlist *) cmd->request_buffer;
355 		tot_dsds = pci_map_sg(ha->pdev, sg, cmd->use_sg,
356 		    cmd->sc_data_direction);
357 		if (tot_dsds == 0)
358 			goto queuing_error;
359 	} else if (cmd->request_bufflen) {
360 		dma_addr_t	req_dma;
361 
362 		req_dma = pci_map_single(ha->pdev, cmd->request_buffer,
363 		    cmd->request_bufflen, cmd->sc_data_direction);
364 		if (dma_mapping_error(req_dma))
365 			goto queuing_error;
366 
367 		sp->dma_handle = req_dma;
368 		tot_dsds = 1;
369 	}
370 
371 	/* Calculate the number of request entries needed. */
372 	req_cnt = ha->isp_ops.calc_req_entries(tot_dsds);
373 	if (ha->req_q_cnt < (req_cnt + 2)) {
374 		cnt = RD_REG_WORD_RELAXED(ISP_REQ_Q_OUT(ha, reg));
375 		if (ha->req_ring_index < cnt)
376 			ha->req_q_cnt = cnt - ha->req_ring_index;
377 		else
378 			ha->req_q_cnt = ha->request_q_length -
379 			    (ha->req_ring_index - cnt);
380 	}
381 	if (ha->req_q_cnt < (req_cnt + 2))
382 		goto queuing_error;
383 
384 	/* Build command packet */
385 	ha->current_outstanding_cmd = handle;
386 	ha->outstanding_cmds[handle] = sp;
387 	sp->ha = ha;
388 	sp->cmd->host_scribble = (unsigned char *)(unsigned long)handle;
389 	ha->req_q_cnt -= req_cnt;
390 
391 	cmd_pkt = (cmd_entry_t *)ha->request_ring_ptr;
392 	cmd_pkt->handle = handle;
393 	/* Zero out remaining portion of packet. */
394 	clr_ptr = (uint32_t *)cmd_pkt + 2;
395 	memset(clr_ptr, 0, REQUEST_ENTRY_SIZE - 8);
396 	cmd_pkt->dseg_count = cpu_to_le16(tot_dsds);
397 
398 	/* Set target ID and LUN number*/
399 	SET_TARGET_ID(ha, cmd_pkt->target, sp->fcport->loop_id);
400 	cmd_pkt->lun = cpu_to_le16(sp->cmd->device->lun);
401 
402 	/* Update tagged queuing modifier */
403 	cmd_pkt->control_flags = __constant_cpu_to_le16(CF_SIMPLE_TAG);
404 	if (scsi_populate_tag_msg(cmd, tag)) {
405 		switch (tag[0]) {
406 		case MSG_HEAD_TAG:
407 			cmd_pkt->control_flags =
408 			    __constant_cpu_to_le16(CF_HEAD_TAG);
409 			break;
410 		case MSG_ORDERED_TAG:
411 			cmd_pkt->control_flags =
412 			    __constant_cpu_to_le16(CF_ORDERED_TAG);
413 			break;
414 		}
415 	}
416 
417 	/* Load SCSI command packet. */
418 	memcpy(cmd_pkt->scsi_cdb, cmd->cmnd, cmd->cmd_len);
419 	cmd_pkt->byte_count = cpu_to_le32((uint32_t)cmd->request_bufflen);
420 
421 	/* Build IOCB segments */
422 	ha->isp_ops.build_iocbs(sp, cmd_pkt, tot_dsds);
423 
424 	/* Set total data segment count. */
425 	cmd_pkt->entry_count = (uint8_t)req_cnt;
426 	wmb();
427 
428 	/* Adjust ring index. */
429 	ha->req_ring_index++;
430 	if (ha->req_ring_index == ha->request_q_length) {
431 		ha->req_ring_index = 0;
432 		ha->request_ring_ptr = ha->request_ring;
433 	} else
434 		ha->request_ring_ptr++;
435 
436 	sp->flags |= SRB_DMA_VALID;
437 	sp->state = SRB_ACTIVE_STATE;
438 
439 	/* Set chip new ring index. */
440 	WRT_REG_WORD(ISP_REQ_Q_IN(ha, reg), ha->req_ring_index);
441 	RD_REG_WORD_RELAXED(ISP_REQ_Q_IN(ha, reg));	/* PCI Posting. */
442 
443 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
444 	return (QLA_SUCCESS);
445 
446 queuing_error:
447 	if (cmd->use_sg && tot_dsds) {
448 		sg = (struct scatterlist *) cmd->request_buffer;
449 		pci_unmap_sg(ha->pdev, sg, cmd->use_sg,
450 		    cmd->sc_data_direction);
451 	} else if (tot_dsds) {
452 		pci_unmap_single(ha->pdev, sp->dma_handle,
453 		    cmd->request_bufflen, cmd->sc_data_direction);
454 	}
455 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
456 
457 	return (QLA_FUNCTION_FAILED);
458 }
459 
460 /**
461  * qla2x00_marker() - Send a marker IOCB to the firmware.
462  * @ha: HA context
463  * @loop_id: loop ID
464  * @lun: LUN
465  * @type: marker modifier
466  *
467  * Can be called from both normal and interrupt context.
468  *
469  * Returns non-zero if a failure occured, else zero.
470  */
471 int
472 __qla2x00_marker(scsi_qla_host_t *ha, uint16_t loop_id, uint16_t lun,
473     uint8_t type)
474 {
475 	mrk_entry_t *mrk;
476 	struct mrk_entry_24xx *mrk24;
477 
478 	mrk24 = NULL;
479 	mrk = (mrk_entry_t *)qla2x00_req_pkt(ha);
480 	if (mrk == NULL) {
481 		DEBUG2_3(printk("%s(%ld): failed to allocate Marker IOCB.\n",
482 		    __func__, ha->host_no));
483 
484 		return (QLA_FUNCTION_FAILED);
485 	}
486 
487 	mrk->entry_type = MARKER_TYPE;
488 	mrk->modifier = type;
489 	if (type != MK_SYNC_ALL) {
490 		if (IS_QLA24XX(ha) || IS_QLA25XX(ha)) {
491 			mrk24 = (struct mrk_entry_24xx *) mrk;
492 			mrk24->nport_handle = cpu_to_le16(loop_id);
493 			mrk24->lun[1] = LSB(lun);
494 			mrk24->lun[2] = MSB(lun);
495 		} else {
496 			SET_TARGET_ID(ha, mrk->target, loop_id);
497 			mrk->lun = cpu_to_le16(lun);
498 		}
499 	}
500 	wmb();
501 
502 	qla2x00_isp_cmd(ha);
503 
504 	return (QLA_SUCCESS);
505 }
506 
507 int
508 qla2x00_marker(scsi_qla_host_t *ha, uint16_t loop_id, uint16_t lun,
509     uint8_t type)
510 {
511 	int ret;
512 	unsigned long flags = 0;
513 
514 	spin_lock_irqsave(&ha->hardware_lock, flags);
515 	ret = __qla2x00_marker(ha, loop_id, lun, type);
516 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
517 
518 	return (ret);
519 }
520 
521 /**
522  * qla2x00_req_pkt() - Retrieve a request packet from the request ring.
523  * @ha: HA context
524  *
525  * Note: The caller must hold the hardware lock before calling this routine.
526  *
527  * Returns NULL if function failed, else, a pointer to the request packet.
528  */
529 static request_t *
530 qla2x00_req_pkt(scsi_qla_host_t *ha)
531 {
532 	device_reg_t __iomem *reg = ha->iobase;
533 	request_t	*pkt = NULL;
534 	uint16_t	cnt;
535 	uint32_t	*dword_ptr;
536 	uint32_t	timer;
537 	uint16_t	req_cnt = 1;
538 
539 	/* Wait 1 second for slot. */
540 	for (timer = HZ; timer; timer--) {
541 		if ((req_cnt + 2) >= ha->req_q_cnt) {
542 			/* Calculate number of free request entries. */
543 			if (IS_QLA24XX(ha) || IS_QLA25XX(ha))
544 				cnt = (uint16_t)RD_REG_DWORD(
545 				    &reg->isp24.req_q_out);
546 			else
547 				cnt = qla2x00_debounce_register(
548 				    ISP_REQ_Q_OUT(ha, &reg->isp));
549 			if  (ha->req_ring_index < cnt)
550 				ha->req_q_cnt = cnt - ha->req_ring_index;
551 			else
552 				ha->req_q_cnt = ha->request_q_length -
553 				    (ha->req_ring_index - cnt);
554 		}
555 		/* If room for request in request ring. */
556 		if ((req_cnt + 2) < ha->req_q_cnt) {
557 			ha->req_q_cnt--;
558 			pkt = ha->request_ring_ptr;
559 
560 			/* Zero out packet. */
561 			dword_ptr = (uint32_t *)pkt;
562 			for (cnt = 0; cnt < REQUEST_ENTRY_SIZE / 4; cnt++)
563 				*dword_ptr++ = 0;
564 
565 			/* Set system defined field. */
566 			pkt->sys_define = (uint8_t)ha->req_ring_index;
567 
568 			/* Set entry count. */
569 			pkt->entry_count = 1;
570 
571 			break;
572 		}
573 
574 		/* Release ring specific lock */
575 		spin_unlock(&ha->hardware_lock);
576 
577 		udelay(2);   /* 2 us */
578 
579 		/* Check for pending interrupts. */
580 		/* During init we issue marker directly */
581 		if (!ha->marker_needed)
582 			qla2x00_poll(ha);
583 
584 		spin_lock_irq(&ha->hardware_lock);
585 	}
586 	if (!pkt) {
587 		DEBUG2_3(printk("%s(): **** FAILED ****\n", __func__));
588 	}
589 
590 	return (pkt);
591 }
592 
593 /**
594  * qla2x00_isp_cmd() - Modify the request ring pointer.
595  * @ha: HA context
596  *
597  * Note: The caller must hold the hardware lock before calling this routine.
598  */
599 void
600 qla2x00_isp_cmd(scsi_qla_host_t *ha)
601 {
602 	device_reg_t __iomem *reg = ha->iobase;
603 
604 	DEBUG5(printk("%s(): IOCB data:\n", __func__));
605 	DEBUG5(qla2x00_dump_buffer(
606 	    (uint8_t *)ha->request_ring_ptr, REQUEST_ENTRY_SIZE));
607 
608 	/* Adjust ring index. */
609 	ha->req_ring_index++;
610 	if (ha->req_ring_index == ha->request_q_length) {
611 		ha->req_ring_index = 0;
612 		ha->request_ring_ptr = ha->request_ring;
613 	} else
614 		ha->request_ring_ptr++;
615 
616 	/* Set chip new ring index. */
617 	if (IS_QLA24XX(ha) || IS_QLA25XX(ha)) {
618 		WRT_REG_DWORD(&reg->isp24.req_q_in, ha->req_ring_index);
619 		RD_REG_DWORD_RELAXED(&reg->isp24.req_q_in);
620 	} else {
621 		WRT_REG_WORD(ISP_REQ_Q_IN(ha, &reg->isp), ha->req_ring_index);
622 		RD_REG_WORD_RELAXED(ISP_REQ_Q_IN(ha, &reg->isp));
623 	}
624 
625 }
626 
627 /**
628  * qla24xx_calc_iocbs() - Determine number of Command Type 3 and
629  * Continuation Type 1 IOCBs to allocate.
630  *
631  * @dsds: number of data segment decriptors needed
632  *
633  * Returns the number of IOCB entries needed to store @dsds.
634  */
635 static inline uint16_t
636 qla24xx_calc_iocbs(uint16_t dsds)
637 {
638 	uint16_t iocbs;
639 
640 	iocbs = 1;
641 	if (dsds > 1) {
642 		iocbs += (dsds - 1) / 5;
643 		if ((dsds - 1) % 5)
644 			iocbs++;
645 	}
646 	return iocbs;
647 }
648 
649 /**
650  * qla24xx_build_scsi_iocbs() - Build IOCB command utilizing Command Type 7
651  * IOCB types.
652  *
653  * @sp: SRB command to process
654  * @cmd_pkt: Command type 3 IOCB
655  * @tot_dsds: Total number of segments to transfer
656  */
657 static inline void
658 qla24xx_build_scsi_iocbs(srb_t *sp, struct cmd_type_7 *cmd_pkt,
659     uint16_t tot_dsds)
660 {
661 	uint16_t	avail_dsds;
662 	uint32_t	*cur_dsd;
663 	scsi_qla_host_t	*ha;
664 	struct scsi_cmnd *cmd;
665 
666 	cmd = sp->cmd;
667 
668 	/* Update entry type to indicate Command Type 3 IOCB */
669 	*((uint32_t *)(&cmd_pkt->entry_type)) =
670 	    __constant_cpu_to_le32(COMMAND_TYPE_7);
671 
672 	/* No data transfer */
673 	if (cmd->request_bufflen == 0 || cmd->sc_data_direction == DMA_NONE) {
674 		cmd_pkt->byte_count = __constant_cpu_to_le32(0);
675 		return;
676 	}
677 
678 	ha = sp->ha;
679 
680 	/* Set transfer direction */
681 	if (cmd->sc_data_direction == DMA_TO_DEVICE)
682 		cmd_pkt->task_mgmt_flags =
683 		    __constant_cpu_to_le16(TMF_WRITE_DATA);
684 	else if (cmd->sc_data_direction == DMA_FROM_DEVICE)
685 		cmd_pkt->task_mgmt_flags =
686 		    __constant_cpu_to_le16(TMF_READ_DATA);
687 
688 	/* One DSD is available in the Command Type 3 IOCB */
689 	avail_dsds = 1;
690 	cur_dsd = (uint32_t *)&cmd_pkt->dseg_0_address;
691 
692 	/* Load data segments */
693 	if (cmd->use_sg != 0) {
694 		struct	scatterlist *cur_seg;
695 		struct	scatterlist *end_seg;
696 
697 		cur_seg = (struct scatterlist *)cmd->request_buffer;
698 		end_seg = cur_seg + tot_dsds;
699 		while (cur_seg < end_seg) {
700 			dma_addr_t	sle_dma;
701 			cont_a64_entry_t *cont_pkt;
702 
703 			/* Allocate additional continuation packets? */
704 			if (avail_dsds == 0) {
705 				/*
706 				 * Five DSDs are available in the Continuation
707 				 * Type 1 IOCB.
708 				 */
709 				cont_pkt = qla2x00_prep_cont_type1_iocb(ha);
710 				cur_dsd = (uint32_t *)cont_pkt->dseg_0_address;
711 				avail_dsds = 5;
712 			}
713 
714 			sle_dma = sg_dma_address(cur_seg);
715 			*cur_dsd++ = cpu_to_le32(LSD(sle_dma));
716 			*cur_dsd++ = cpu_to_le32(MSD(sle_dma));
717 			*cur_dsd++ = cpu_to_le32(sg_dma_len(cur_seg));
718 			avail_dsds--;
719 
720 			cur_seg++;
721 		}
722 	} else {
723 		*cur_dsd++ = cpu_to_le32(LSD(sp->dma_handle));
724 		*cur_dsd++ = cpu_to_le32(MSD(sp->dma_handle));
725 		*cur_dsd++ = cpu_to_le32(cmd->request_bufflen);
726 	}
727 }
728 
729 
730 /**
731  * qla24xx_start_scsi() - Send a SCSI command to the ISP
732  * @sp: command to send to the ISP
733  *
734  * Returns non-zero if a failure occured, else zero.
735  */
736 int
737 qla24xx_start_scsi(srb_t *sp)
738 {
739 	int		ret;
740 	unsigned long   flags;
741 	scsi_qla_host_t	*ha;
742 	struct scsi_cmnd *cmd;
743 	uint32_t	*clr_ptr;
744 	uint32_t        index;
745 	uint32_t	handle;
746 	struct cmd_type_7 *cmd_pkt;
747 	struct scatterlist *sg;
748 	uint16_t	cnt;
749 	uint16_t	req_cnt;
750 	uint16_t	tot_dsds;
751 	struct device_reg_24xx __iomem *reg;
752 	char		tag[2];
753 
754 	/* Setup device pointers. */
755 	ret = 0;
756 	ha = sp->ha;
757 	reg = &ha->iobase->isp24;
758 	cmd = sp->cmd;
759 	/* So we know we haven't pci_map'ed anything yet */
760 	tot_dsds = 0;
761 
762 	/* Send marker if required */
763 	if (ha->marker_needed != 0) {
764 		if (qla2x00_marker(ha, 0, 0, MK_SYNC_ALL) != QLA_SUCCESS) {
765 			return QLA_FUNCTION_FAILED;
766 		}
767 		ha->marker_needed = 0;
768 	}
769 
770 	/* Acquire ring specific lock */
771 	spin_lock_irqsave(&ha->hardware_lock, flags);
772 
773 	/* Check for room in outstanding command list. */
774 	handle = ha->current_outstanding_cmd;
775 	for (index = 1; index < MAX_OUTSTANDING_COMMANDS; index++) {
776 		handle++;
777 		if (handle == MAX_OUTSTANDING_COMMANDS)
778 			handle = 1;
779 		if (ha->outstanding_cmds[handle] == 0)
780 			break;
781 	}
782 	if (index == MAX_OUTSTANDING_COMMANDS)
783 		goto queuing_error;
784 
785 	/* Map the sg table so we have an accurate count of sg entries needed */
786 	if (cmd->use_sg) {
787 		sg = (struct scatterlist *) cmd->request_buffer;
788 		tot_dsds = pci_map_sg(ha->pdev, sg, cmd->use_sg,
789 		    cmd->sc_data_direction);
790 		if (tot_dsds == 0)
791 			goto queuing_error;
792 	} else if (cmd->request_bufflen) {
793 		dma_addr_t      req_dma;
794 
795 		req_dma = pci_map_single(ha->pdev, cmd->request_buffer,
796 		    cmd->request_bufflen, cmd->sc_data_direction);
797 		if (dma_mapping_error(req_dma))
798 			goto queuing_error;
799 
800 		sp->dma_handle = req_dma;
801 		tot_dsds = 1;
802 	}
803 
804 	req_cnt = qla24xx_calc_iocbs(tot_dsds);
805 	if (ha->req_q_cnt < (req_cnt + 2)) {
806 		cnt = (uint16_t)RD_REG_DWORD_RELAXED(&reg->req_q_out);
807 		if (ha->req_ring_index < cnt)
808 			ha->req_q_cnt = cnt - ha->req_ring_index;
809 		else
810 			ha->req_q_cnt = ha->request_q_length -
811 				(ha->req_ring_index - cnt);
812 	}
813 	if (ha->req_q_cnt < (req_cnt + 2))
814 		goto queuing_error;
815 
816 	/* Build command packet. */
817 	ha->current_outstanding_cmd = handle;
818 	ha->outstanding_cmds[handle] = sp;
819 	sp->ha = ha;
820 	sp->cmd->host_scribble = (unsigned char *)(unsigned long)handle;
821 	ha->req_q_cnt -= req_cnt;
822 
823 	cmd_pkt = (struct cmd_type_7 *)ha->request_ring_ptr;
824 	cmd_pkt->handle = handle;
825 
826 	/* Zero out remaining portion of packet. */
827 	clr_ptr = (uint32_t *)cmd_pkt + 2;
828 	memset(clr_ptr, 0, REQUEST_ENTRY_SIZE - 8);
829 	cmd_pkt->dseg_count = cpu_to_le16(tot_dsds);
830 
831 	/* Set NPORT-ID and LUN number*/
832 	cmd_pkt->nport_handle = cpu_to_le16(sp->fcport->loop_id);
833 	cmd_pkt->port_id[0] = sp->fcport->d_id.b.al_pa;
834 	cmd_pkt->port_id[1] = sp->fcport->d_id.b.area;
835 	cmd_pkt->port_id[2] = sp->fcport->d_id.b.domain;
836 
837 	cmd_pkt->lun[1] = LSB(sp->cmd->device->lun);
838 	cmd_pkt->lun[2] = MSB(sp->cmd->device->lun);
839 
840 	/* Update tagged queuing modifier -- default is TSK_SIMPLE (0). */
841 	if (scsi_populate_tag_msg(cmd, tag)) {
842 		switch (tag[0]) {
843 		case MSG_HEAD_TAG:
844 			cmd_pkt->task = TSK_HEAD_OF_QUEUE;
845 			break;
846 		case MSG_ORDERED_TAG:
847 			cmd_pkt->task = TSK_ORDERED;
848 			break;
849 		}
850 	}
851 
852 	/* Load SCSI command packet. */
853 	memcpy(cmd_pkt->fcp_cdb, cmd->cmnd, cmd->cmd_len);
854 	host_to_fcp_swap(cmd_pkt->fcp_cdb, sizeof(cmd_pkt->fcp_cdb));
855 
856 	cmd_pkt->byte_count = cpu_to_le32((uint32_t)cmd->request_bufflen);
857 
858 	/* Build IOCB segments */
859 	qla24xx_build_scsi_iocbs(sp, cmd_pkt, tot_dsds);
860 
861 	/* Set total data segment count. */
862 	cmd_pkt->entry_count = (uint8_t)req_cnt;
863 	wmb();
864 
865 	/* Adjust ring index. */
866 	ha->req_ring_index++;
867 	if (ha->req_ring_index == ha->request_q_length) {
868 		ha->req_ring_index = 0;
869 		ha->request_ring_ptr = ha->request_ring;
870 	} else
871 		ha->request_ring_ptr++;
872 
873 	sp->flags |= SRB_DMA_VALID;
874 	sp->state = SRB_ACTIVE_STATE;
875 
876 	/* Set chip new ring index. */
877 	WRT_REG_DWORD(&reg->req_q_in, ha->req_ring_index);
878 	RD_REG_DWORD_RELAXED(&reg->req_q_in);		/* PCI Posting. */
879 
880 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
881 	return QLA_SUCCESS;
882 
883 queuing_error:
884 	if (cmd->use_sg && tot_dsds) {
885 		sg = (struct scatterlist *) cmd->request_buffer;
886 		pci_unmap_sg(ha->pdev, sg, cmd->use_sg,
887 		    cmd->sc_data_direction);
888 	} else if (tot_dsds) {
889 		pci_unmap_single(ha->pdev, sp->dma_handle,
890 		    cmd->request_bufflen, cmd->sc_data_direction);
891 	}
892 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
893 
894 	return QLA_FUNCTION_FAILED;
895 }
896