xref: /openbmc/linux/drivers/scsi/csiostor/csio_isr.c (revision 2359ccdd)
1 /*
2  * This file is part of the Chelsio FCoE driver for Linux.
3  *
4  * Copyright (c) 2008-2012 Chelsio Communications, Inc. All rights reserved.
5  *
6  * This software is available to you under a choice of one of two
7  * licenses.  You may choose to be licensed under the terms of the GNU
8  * General Public License (GPL) Version 2, available from the file
9  * COPYING in the main directory of this source tree, or the
10  * OpenIB.org BSD license below:
11  *
12  *     Redistribution and use in source and binary forms, with or
13  *     without modification, are permitted provided that the following
14  *     conditions are met:
15  *
16  *      - Redistributions of source code must retain the above
17  *        copyright notice, this list of conditions and the following
18  *        disclaimer.
19  *
20  *      - Redistributions in binary form must reproduce the above
21  *        copyright notice, this list of conditions and the following
22  *        disclaimer in the documentation and/or other materials
23  *        provided with the distribution.
24  *
25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32  * SOFTWARE.
33  */
34 
35 #include <linux/kernel.h>
36 #include <linux/pci.h>
37 #include <linux/interrupt.h>
38 #include <linux/cpumask.h>
39 #include <linux/string.h>
40 
41 #include "csio_init.h"
42 #include "csio_hw.h"
43 
44 static irqreturn_t
45 csio_nondata_isr(int irq, void *dev_id)
46 {
47 	struct csio_hw *hw = (struct csio_hw *) dev_id;
48 	int rv;
49 	unsigned long flags;
50 
51 	if (unlikely(!hw))
52 		return IRQ_NONE;
53 
54 	if (unlikely(pci_channel_offline(hw->pdev))) {
55 		CSIO_INC_STATS(hw, n_pcich_offline);
56 		return IRQ_NONE;
57 	}
58 
59 	spin_lock_irqsave(&hw->lock, flags);
60 	csio_hw_slow_intr_handler(hw);
61 	rv = csio_mb_isr_handler(hw);
62 
63 	if (rv == 0 && !(hw->flags & CSIO_HWF_FWEVT_PENDING)) {
64 		hw->flags |= CSIO_HWF_FWEVT_PENDING;
65 		spin_unlock_irqrestore(&hw->lock, flags);
66 		schedule_work(&hw->evtq_work);
67 		return IRQ_HANDLED;
68 	}
69 	spin_unlock_irqrestore(&hw->lock, flags);
70 	return IRQ_HANDLED;
71 }
72 
73 /*
74  * csio_fwevt_handler - Common FW event handler routine.
75  * @hw: HW module.
76  *
77  * This is the ISR for FW events. It is shared b/w MSIX
78  * and INTx handlers.
79  */
80 static void
81 csio_fwevt_handler(struct csio_hw *hw)
82 {
83 	int rv;
84 	unsigned long flags;
85 
86 	rv = csio_fwevtq_handler(hw);
87 
88 	spin_lock_irqsave(&hw->lock, flags);
89 	if (rv == 0 && !(hw->flags & CSIO_HWF_FWEVT_PENDING)) {
90 		hw->flags |= CSIO_HWF_FWEVT_PENDING;
91 		spin_unlock_irqrestore(&hw->lock, flags);
92 		schedule_work(&hw->evtq_work);
93 		return;
94 	}
95 	spin_unlock_irqrestore(&hw->lock, flags);
96 
97 } /* csio_fwevt_handler */
98 
99 /*
100  * csio_fwevt_isr() - FW events MSIX ISR
101  * @irq:
102  * @dev_id:
103  *
104  * Process WRs on the FW event queue.
105  *
106  */
107 static irqreturn_t
108 csio_fwevt_isr(int irq, void *dev_id)
109 {
110 	struct csio_hw *hw = (struct csio_hw *) dev_id;
111 
112 	if (unlikely(!hw))
113 		return IRQ_NONE;
114 
115 	if (unlikely(pci_channel_offline(hw->pdev))) {
116 		CSIO_INC_STATS(hw, n_pcich_offline);
117 		return IRQ_NONE;
118 	}
119 
120 	csio_fwevt_handler(hw);
121 
122 	return IRQ_HANDLED;
123 }
124 
125 /*
126  * csio_fwevt_isr() - INTx wrapper for handling FW events.
127  * @irq:
128  * @dev_id:
129  */
130 void
131 csio_fwevt_intx_handler(struct csio_hw *hw, void *wr, uint32_t len,
132 			   struct csio_fl_dma_buf *flb, void *priv)
133 {
134 	csio_fwevt_handler(hw);
135 } /* csio_fwevt_intx_handler */
136 
137 /*
138  * csio_process_scsi_cmpl - Process a SCSI WR completion.
139  * @hw: HW module.
140  * @wr: The completed WR from the ingress queue.
141  * @len: Length of the WR.
142  * @flb: Freelist buffer array.
143  *
144  */
145 static void
146 csio_process_scsi_cmpl(struct csio_hw *hw, void *wr, uint32_t len,
147 			struct csio_fl_dma_buf *flb, void *cbfn_q)
148 {
149 	struct csio_ioreq *ioreq;
150 	uint8_t *scsiwr;
151 	uint8_t subop;
152 	void *cmnd;
153 	unsigned long flags;
154 
155 	ioreq = csio_scsi_cmpl_handler(hw, wr, len, flb, NULL, &scsiwr);
156 	if (likely(ioreq)) {
157 		if (unlikely(*scsiwr == FW_SCSI_ABRT_CLS_WR)) {
158 			subop = FW_SCSI_ABRT_CLS_WR_SUB_OPCODE_GET(
159 					((struct fw_scsi_abrt_cls_wr *)
160 					    scsiwr)->sub_opcode_to_chk_all_io);
161 
162 			csio_dbg(hw, "%s cmpl recvd ioreq:%p status:%d\n",
163 				    subop ? "Close" : "Abort",
164 				    ioreq, ioreq->wr_status);
165 
166 			spin_lock_irqsave(&hw->lock, flags);
167 			if (subop)
168 				csio_scsi_closed(ioreq,
169 						 (struct list_head *)cbfn_q);
170 			else
171 				csio_scsi_aborted(ioreq,
172 						  (struct list_head *)cbfn_q);
173 			/*
174 			 * We call scsi_done for I/Os that driver thinks aborts
175 			 * have timed out. If there is a race caused by FW
176 			 * completing abort at the exact same time that the
177 			 * driver has deteced the abort timeout, the following
178 			 * check prevents calling of scsi_done twice for the
179 			 * same command: once from the eh_abort_handler, another
180 			 * from csio_scsi_isr_handler(). This also avoids the
181 			 * need to check if csio_scsi_cmnd(req) is NULL in the
182 			 * fast path.
183 			 */
184 			cmnd = csio_scsi_cmnd(ioreq);
185 			if (unlikely(cmnd == NULL))
186 				list_del_init(&ioreq->sm.sm_list);
187 
188 			spin_unlock_irqrestore(&hw->lock, flags);
189 
190 			if (unlikely(cmnd == NULL))
191 				csio_put_scsi_ioreq_lock(hw,
192 						csio_hw_to_scsim(hw), ioreq);
193 		} else {
194 			spin_lock_irqsave(&hw->lock, flags);
195 			csio_scsi_completed(ioreq, (struct list_head *)cbfn_q);
196 			spin_unlock_irqrestore(&hw->lock, flags);
197 		}
198 	}
199 }
200 
201 /*
202  * csio_scsi_isr_handler() - Common SCSI ISR handler.
203  * @iq: Ingress queue pointer.
204  *
205  * Processes SCSI completions on the SCSI IQ indicated by scm->iq_idx
206  * by calling csio_wr_process_iq_idx. If there are completions on the
207  * isr_cbfn_q, yank them out into a local queue and call their io_cbfns.
208  * Once done, add these completions onto the freelist.
209  * This routine is shared b/w MSIX and INTx.
210  */
211 static inline irqreturn_t
212 csio_scsi_isr_handler(struct csio_q *iq)
213 {
214 	struct csio_hw *hw = (struct csio_hw *)iq->owner;
215 	LIST_HEAD(cbfn_q);
216 	struct list_head *tmp;
217 	struct csio_scsim *scm;
218 	struct csio_ioreq *ioreq;
219 	int isr_completions = 0;
220 
221 	scm = csio_hw_to_scsim(hw);
222 
223 	if (unlikely(csio_wr_process_iq(hw, iq, csio_process_scsi_cmpl,
224 					&cbfn_q) != 0))
225 		return IRQ_NONE;
226 
227 	/* Call back the completion routines */
228 	list_for_each(tmp, &cbfn_q) {
229 		ioreq = (struct csio_ioreq *)tmp;
230 		isr_completions++;
231 		ioreq->io_cbfn(hw, ioreq);
232 		/* Release ddp buffer if used for this req */
233 		if (unlikely(ioreq->dcopy))
234 			csio_put_scsi_ddp_list_lock(hw, scm, &ioreq->gen_list,
235 						    ioreq->nsge);
236 	}
237 
238 	if (isr_completions) {
239 		/* Return the ioreqs back to ioreq->freelist */
240 		csio_put_scsi_ioreq_list_lock(hw, scm, &cbfn_q,
241 					      isr_completions);
242 	}
243 
244 	return IRQ_HANDLED;
245 }
246 
247 /*
248  * csio_scsi_isr() - SCSI MSIX handler
249  * @irq:
250  * @dev_id:
251  *
252  * This is the top level SCSI MSIX handler. Calls csio_scsi_isr_handler()
253  * for handling SCSI completions.
254  */
255 static irqreturn_t
256 csio_scsi_isr(int irq, void *dev_id)
257 {
258 	struct csio_q *iq = (struct csio_q *) dev_id;
259 	struct csio_hw *hw;
260 
261 	if (unlikely(!iq))
262 		return IRQ_NONE;
263 
264 	hw = (struct csio_hw *)iq->owner;
265 
266 	if (unlikely(pci_channel_offline(hw->pdev))) {
267 		CSIO_INC_STATS(hw, n_pcich_offline);
268 		return IRQ_NONE;
269 	}
270 
271 	csio_scsi_isr_handler(iq);
272 
273 	return IRQ_HANDLED;
274 }
275 
276 /*
277  * csio_scsi_intx_handler() - SCSI INTx handler
278  * @irq:
279  * @dev_id:
280  *
281  * This is the top level SCSI INTx handler. Calls csio_scsi_isr_handler()
282  * for handling SCSI completions.
283  */
284 void
285 csio_scsi_intx_handler(struct csio_hw *hw, void *wr, uint32_t len,
286 			struct csio_fl_dma_buf *flb, void *priv)
287 {
288 	struct csio_q *iq = priv;
289 
290 	csio_scsi_isr_handler(iq);
291 
292 } /* csio_scsi_intx_handler */
293 
294 /*
295  * csio_fcoe_isr() - INTx/MSI interrupt service routine for FCoE.
296  * @irq:
297  * @dev_id:
298  *
299  *
300  */
301 static irqreturn_t
302 csio_fcoe_isr(int irq, void *dev_id)
303 {
304 	struct csio_hw *hw = (struct csio_hw *) dev_id;
305 	struct csio_q *intx_q = NULL;
306 	int rv;
307 	irqreturn_t ret = IRQ_NONE;
308 	unsigned long flags;
309 
310 	if (unlikely(!hw))
311 		return IRQ_NONE;
312 
313 	if (unlikely(pci_channel_offline(hw->pdev))) {
314 		CSIO_INC_STATS(hw, n_pcich_offline);
315 		return IRQ_NONE;
316 	}
317 
318 	/* Disable the interrupt for this PCI function. */
319 	if (hw->intr_mode == CSIO_IM_INTX)
320 		csio_wr_reg32(hw, 0, MYPF_REG(PCIE_PF_CLI_A));
321 
322 	/*
323 	 * The read in the following function will flush the
324 	 * above write.
325 	 */
326 	if (csio_hw_slow_intr_handler(hw))
327 		ret = IRQ_HANDLED;
328 
329 	/* Get the INTx Forward interrupt IQ. */
330 	intx_q = csio_get_q(hw, hw->intr_iq_idx);
331 
332 	CSIO_DB_ASSERT(intx_q);
333 
334 	/* IQ handler is not possible for intx_q, hence pass in NULL */
335 	if (likely(csio_wr_process_iq(hw, intx_q, NULL, NULL) == 0))
336 		ret = IRQ_HANDLED;
337 
338 	spin_lock_irqsave(&hw->lock, flags);
339 	rv = csio_mb_isr_handler(hw);
340 	if (rv == 0 && !(hw->flags & CSIO_HWF_FWEVT_PENDING)) {
341 		hw->flags |= CSIO_HWF_FWEVT_PENDING;
342 		spin_unlock_irqrestore(&hw->lock, flags);
343 		schedule_work(&hw->evtq_work);
344 		return IRQ_HANDLED;
345 	}
346 	spin_unlock_irqrestore(&hw->lock, flags);
347 
348 	return ret;
349 }
350 
351 static void
352 csio_add_msix_desc(struct csio_hw *hw)
353 {
354 	int i;
355 	struct csio_msix_entries *entryp = &hw->msix_entries[0];
356 	int k = CSIO_EXTRA_VECS;
357 	int len = sizeof(entryp->desc) - 1;
358 	int cnt = hw->num_sqsets + k;
359 
360 	/* Non-data vector */
361 	memset(entryp->desc, 0, len + 1);
362 	snprintf(entryp->desc, len, "csio-%02x:%02x:%x-nondata",
363 		 CSIO_PCI_BUS(hw), CSIO_PCI_DEV(hw), CSIO_PCI_FUNC(hw));
364 
365 	entryp++;
366 	memset(entryp->desc, 0, len + 1);
367 	snprintf(entryp->desc, len, "csio-%02x:%02x:%x-fwevt",
368 		 CSIO_PCI_BUS(hw), CSIO_PCI_DEV(hw), CSIO_PCI_FUNC(hw));
369 	entryp++;
370 
371 	/* Name SCSI vecs */
372 	for (i = k; i < cnt; i++, entryp++) {
373 		memset(entryp->desc, 0, len + 1);
374 		snprintf(entryp->desc, len, "csio-%02x:%02x:%x-scsi%d",
375 			 CSIO_PCI_BUS(hw), CSIO_PCI_DEV(hw),
376 			 CSIO_PCI_FUNC(hw), i - CSIO_EXTRA_VECS);
377 	}
378 }
379 
380 int
381 csio_request_irqs(struct csio_hw *hw)
382 {
383 	int rv, i, j, k = 0;
384 	struct csio_msix_entries *entryp = &hw->msix_entries[0];
385 	struct csio_scsi_cpu_info *info;
386 	struct pci_dev *pdev = hw->pdev;
387 
388 	if (hw->intr_mode != CSIO_IM_MSIX) {
389 		rv = request_irq(pci_irq_vector(pdev, 0), csio_fcoe_isr,
390 				hw->intr_mode == CSIO_IM_MSI ? 0 : IRQF_SHARED,
391 				KBUILD_MODNAME, hw);
392 		if (rv) {
393 			csio_err(hw, "Failed to allocate interrupt line.\n");
394 			goto out_free_irqs;
395 		}
396 
397 		goto out;
398 	}
399 
400 	/* Add the MSIX vector descriptions */
401 	csio_add_msix_desc(hw);
402 
403 	rv = request_irq(pci_irq_vector(pdev, k), csio_nondata_isr, 0,
404 			 entryp[k].desc, hw);
405 	if (rv) {
406 		csio_err(hw, "IRQ request failed for vec %d err:%d\n",
407 			 pci_irq_vector(pdev, k), rv);
408 		goto out_free_irqs;
409 	}
410 
411 	entryp[k++].dev_id = hw;
412 
413 	rv = request_irq(pci_irq_vector(pdev, k), csio_fwevt_isr, 0,
414 			 entryp[k].desc, hw);
415 	if (rv) {
416 		csio_err(hw, "IRQ request failed for vec %d err:%d\n",
417 			 pci_irq_vector(pdev, k), rv);
418 		goto out_free_irqs;
419 	}
420 
421 	entryp[k++].dev_id = (void *)hw;
422 
423 	/* Allocate IRQs for SCSI */
424 	for (i = 0; i < hw->num_pports; i++) {
425 		info = &hw->scsi_cpu_info[i];
426 		for (j = 0; j < info->max_cpus; j++, k++) {
427 			struct csio_scsi_qset *sqset = &hw->sqset[i][j];
428 			struct csio_q *q = hw->wrm.q_arr[sqset->iq_idx];
429 
430 			rv = request_irq(pci_irq_vector(pdev, k), csio_scsi_isr, 0,
431 					 entryp[k].desc, q);
432 			if (rv) {
433 				csio_err(hw,
434 				       "IRQ request failed for vec %d err:%d\n",
435 				       pci_irq_vector(pdev, k), rv);
436 				goto out_free_irqs;
437 			}
438 
439 			entryp[k].dev_id = q;
440 
441 		} /* for all scsi cpus */
442 	} /* for all ports */
443 
444 out:
445 	hw->flags |= CSIO_HWF_HOST_INTR_ENABLED;
446 	return 0;
447 
448 out_free_irqs:
449 	for (i = 0; i < k; i++)
450 		free_irq(pci_irq_vector(pdev, i), hw->msix_entries[i].dev_id);
451 	pci_free_irq_vectors(hw->pdev);
452 	return -EINVAL;
453 }
454 
455 /* Reduce per-port max possible CPUs */
456 static void
457 csio_reduce_sqsets(struct csio_hw *hw, int cnt)
458 {
459 	int i;
460 	struct csio_scsi_cpu_info *info;
461 
462 	while (cnt < hw->num_sqsets) {
463 		for (i = 0; i < hw->num_pports; i++) {
464 			info = &hw->scsi_cpu_info[i];
465 			if (info->max_cpus > 1) {
466 				info->max_cpus--;
467 				hw->num_sqsets--;
468 				if (hw->num_sqsets <= cnt)
469 					break;
470 			}
471 		}
472 	}
473 
474 	csio_dbg(hw, "Reduced sqsets to %d\n", hw->num_sqsets);
475 }
476 
477 static int
478 csio_enable_msix(struct csio_hw *hw)
479 {
480 	int i, j, k, n, min, cnt;
481 	int extra = CSIO_EXTRA_VECS;
482 	struct csio_scsi_cpu_info *info;
483 	struct irq_affinity desc = { .pre_vectors = 2 };
484 
485 	min = hw->num_pports + extra;
486 	cnt = hw->num_sqsets + extra;
487 
488 	/* Max vectors required based on #niqs configured in fw */
489 	if (hw->flags & CSIO_HWF_USING_SOFT_PARAMS || !csio_is_hw_master(hw))
490 		cnt = min_t(uint8_t, hw->cfg_niq, cnt);
491 
492 	csio_dbg(hw, "FW supp #niq:%d, trying %d msix's\n", hw->cfg_niq, cnt);
493 
494 	cnt = pci_alloc_irq_vectors_affinity(hw->pdev, min, cnt,
495 			PCI_IRQ_MSIX | PCI_IRQ_AFFINITY, &desc);
496 	if (cnt < 0)
497 		return cnt;
498 
499 	if (cnt < (hw->num_sqsets + extra)) {
500 		csio_dbg(hw, "Reducing sqsets to %d\n", cnt - extra);
501 		csio_reduce_sqsets(hw, cnt - extra);
502 	}
503 
504 	/* Distribute vectors */
505 	k = 0;
506 	csio_set_nondata_intr_idx(hw, k);
507 	csio_set_mb_intr_idx(csio_hw_to_mbm(hw), k++);
508 	csio_set_fwevt_intr_idx(hw, k++);
509 
510 	for (i = 0; i < hw->num_pports; i++) {
511 		info = &hw->scsi_cpu_info[i];
512 
513 		for (j = 0; j < hw->num_scsi_msix_cpus; j++) {
514 			n = (j % info->max_cpus) +  k;
515 			hw->sqset[i][j].intr_idx = n;
516 		}
517 
518 		k += info->max_cpus;
519 	}
520 
521 	return 0;
522 }
523 
524 void
525 csio_intr_enable(struct csio_hw *hw)
526 {
527 	hw->intr_mode = CSIO_IM_NONE;
528 	hw->flags &= ~CSIO_HWF_HOST_INTR_ENABLED;
529 
530 	/* Try MSIX, then MSI or fall back to INTx */
531 	if ((csio_msi == 2) && !csio_enable_msix(hw))
532 		hw->intr_mode = CSIO_IM_MSIX;
533 	else {
534 		/* Max iqs required based on #niqs configured in fw */
535 		if (hw->flags & CSIO_HWF_USING_SOFT_PARAMS ||
536 			!csio_is_hw_master(hw)) {
537 			int extra = CSIO_EXTRA_MSI_IQS;
538 
539 			if (hw->cfg_niq < (hw->num_sqsets + extra)) {
540 				csio_dbg(hw, "Reducing sqsets to %d\n",
541 					 hw->cfg_niq - extra);
542 				csio_reduce_sqsets(hw, hw->cfg_niq - extra);
543 			}
544 		}
545 
546 		if ((csio_msi == 1) && !pci_enable_msi(hw->pdev))
547 			hw->intr_mode = CSIO_IM_MSI;
548 		else
549 			hw->intr_mode = CSIO_IM_INTX;
550 	}
551 
552 	csio_dbg(hw, "Using %s interrupt mode.\n",
553 		(hw->intr_mode == CSIO_IM_MSIX) ? "MSIX" :
554 		((hw->intr_mode == CSIO_IM_MSI) ? "MSI" : "INTx"));
555 }
556 
557 void
558 csio_intr_disable(struct csio_hw *hw, bool free)
559 {
560 	csio_hw_intr_disable(hw);
561 
562 	if (free) {
563 		int i;
564 
565 		switch (hw->intr_mode) {
566 		case CSIO_IM_MSIX:
567 			for (i = 0; i < hw->num_sqsets + CSIO_EXTRA_VECS; i++) {
568 				free_irq(pci_irq_vector(hw->pdev, i),
569 					 hw->msix_entries[i].dev_id);
570 			}
571 			break;
572 		case CSIO_IM_MSI:
573 		case CSIO_IM_INTX:
574 			free_irq(pci_irq_vector(hw->pdev, 0), hw);
575 			break;
576 		default:
577 			break;
578 		}
579 	}
580 
581 	pci_free_irq_vectors(hw->pdev);
582 	hw->intr_mode = CSIO_IM_NONE;
583 	hw->flags &= ~CSIO_HWF_HOST_INTR_ENABLED;
584 }
585