xref: /linux/drivers/scsi/fnic/fnic_isr.c (revision 4b660dbd9ee2059850fd30e0df420ca7a38a1856)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2008 Cisco Systems, Inc.  All rights reserved.
4  * Copyright 2007 Nuova Systems, Inc.  All rights reserved.
5  */
6 #include <linux/string.h>
7 #include <linux/errno.h>
8 #include <linux/pci.h>
9 #include <linux/interrupt.h>
10 #include <scsi/libfc.h>
11 #include <scsi/fc_frame.h>
12 #include "vnic_dev.h"
13 #include "vnic_intr.h"
14 #include "vnic_stats.h"
15 #include "fnic_io.h"
16 #include "fnic.h"
17 
18 static irqreturn_t fnic_isr_legacy(int irq, void *data)
19 {
20 	struct fnic *fnic = data;
21 	u32 pba;
22 	unsigned long work_done = 0;
23 
24 	pba = vnic_intr_legacy_pba(fnic->legacy_pba);
25 	if (!pba)
26 		return IRQ_NONE;
27 
28 	fnic->fnic_stats.misc_stats.last_isr_time = jiffies;
29 	atomic64_inc(&fnic->fnic_stats.misc_stats.isr_count);
30 
31 	if (pba & (1 << FNIC_INTX_NOTIFY)) {
32 		vnic_intr_return_all_credits(&fnic->intr[FNIC_INTX_NOTIFY]);
33 		fnic_handle_link_event(fnic);
34 	}
35 
36 	if (pba & (1 << FNIC_INTX_ERR)) {
37 		vnic_intr_return_all_credits(&fnic->intr[FNIC_INTX_ERR]);
38 		fnic_log_q_error(fnic);
39 	}
40 
41 	if (pba & (1 << FNIC_INTX_DUMMY)) {
42 		atomic64_inc(&fnic->fnic_stats.misc_stats.intx_dummy);
43 		vnic_intr_return_all_credits(&fnic->intr[FNIC_INTX_DUMMY]);
44 	}
45 
46 	if (pba & (1 << FNIC_INTX_WQ_RQ_COPYWQ)) {
47 		work_done += fnic_wq_copy_cmpl_handler(fnic, io_completions, FNIC_MQ_CQ_INDEX);
48 		work_done += fnic_wq_cmpl_handler(fnic, -1);
49 		work_done += fnic_rq_cmpl_handler(fnic, -1);
50 
51 		vnic_intr_return_credits(&fnic->intr[FNIC_INTX_WQ_RQ_COPYWQ],
52 					 work_done,
53 					 1 /* unmask intr */,
54 					 1 /* reset intr timer */);
55 	}
56 
57 	return IRQ_HANDLED;
58 }
59 
60 static irqreturn_t fnic_isr_msi(int irq, void *data)
61 {
62 	struct fnic *fnic = data;
63 	unsigned long work_done = 0;
64 
65 	fnic->fnic_stats.misc_stats.last_isr_time = jiffies;
66 	atomic64_inc(&fnic->fnic_stats.misc_stats.isr_count);
67 
68 	work_done += fnic_wq_copy_cmpl_handler(fnic, io_completions, FNIC_MQ_CQ_INDEX);
69 	work_done += fnic_wq_cmpl_handler(fnic, -1);
70 	work_done += fnic_rq_cmpl_handler(fnic, -1);
71 
72 	vnic_intr_return_credits(&fnic->intr[0],
73 				 work_done,
74 				 1 /* unmask intr */,
75 				 1 /* reset intr timer */);
76 
77 	return IRQ_HANDLED;
78 }
79 
80 static irqreturn_t fnic_isr_msix_rq(int irq, void *data)
81 {
82 	struct fnic *fnic = data;
83 	unsigned long rq_work_done = 0;
84 
85 	fnic->fnic_stats.misc_stats.last_isr_time = jiffies;
86 	atomic64_inc(&fnic->fnic_stats.misc_stats.isr_count);
87 
88 	rq_work_done = fnic_rq_cmpl_handler(fnic, -1);
89 	vnic_intr_return_credits(&fnic->intr[FNIC_MSIX_RQ],
90 				 rq_work_done,
91 				 1 /* unmask intr */,
92 				 1 /* reset intr timer */);
93 
94 	return IRQ_HANDLED;
95 }
96 
97 static irqreturn_t fnic_isr_msix_wq(int irq, void *data)
98 {
99 	struct fnic *fnic = data;
100 	unsigned long wq_work_done = 0;
101 
102 	fnic->fnic_stats.misc_stats.last_isr_time = jiffies;
103 	atomic64_inc(&fnic->fnic_stats.misc_stats.isr_count);
104 
105 	wq_work_done = fnic_wq_cmpl_handler(fnic, -1);
106 	vnic_intr_return_credits(&fnic->intr[FNIC_MSIX_WQ],
107 				 wq_work_done,
108 				 1 /* unmask intr */,
109 				 1 /* reset intr timer */);
110 	return IRQ_HANDLED;
111 }
112 
113 static irqreturn_t fnic_isr_msix_wq_copy(int irq, void *data)
114 {
115 	struct fnic *fnic = data;
116 	unsigned long wq_copy_work_done = 0;
117 	int i;
118 
119 	fnic->fnic_stats.misc_stats.last_isr_time = jiffies;
120 	atomic64_inc(&fnic->fnic_stats.misc_stats.isr_count);
121 
122 	i = irq - fnic->msix[0].irq_num;
123 	if (i >= fnic->wq_copy_count + fnic->copy_wq_base ||
124 		i < 0 || fnic->msix[i].irq_num != irq) {
125 		for (i = fnic->copy_wq_base; i < fnic->wq_copy_count + fnic->copy_wq_base ; i++) {
126 			if (fnic->msix[i].irq_num == irq)
127 				break;
128 		}
129 	}
130 
131 	wq_copy_work_done = fnic_wq_copy_cmpl_handler(fnic, io_completions, i);
132 	vnic_intr_return_credits(&fnic->intr[i],
133 				 wq_copy_work_done,
134 				 1 /* unmask intr */,
135 				 1 /* reset intr timer */);
136 	return IRQ_HANDLED;
137 }
138 
139 static irqreturn_t fnic_isr_msix_err_notify(int irq, void *data)
140 {
141 	struct fnic *fnic = data;
142 
143 	fnic->fnic_stats.misc_stats.last_isr_time = jiffies;
144 	atomic64_inc(&fnic->fnic_stats.misc_stats.isr_count);
145 
146 	vnic_intr_return_all_credits(&fnic->intr[fnic->err_intr_offset]);
147 	fnic_log_q_error(fnic);
148 	fnic_handle_link_event(fnic);
149 
150 	return IRQ_HANDLED;
151 }
152 
153 void fnic_free_intr(struct fnic *fnic)
154 {
155 	int i;
156 
157 	switch (vnic_dev_get_intr_mode(fnic->vdev)) {
158 	case VNIC_DEV_INTR_MODE_INTX:
159 	case VNIC_DEV_INTR_MODE_MSI:
160 		free_irq(pci_irq_vector(fnic->pdev, 0), fnic);
161 		break;
162 
163 	case VNIC_DEV_INTR_MODE_MSIX:
164 		for (i = 0; i < ARRAY_SIZE(fnic->msix); i++)
165 			if (fnic->msix[i].requested)
166 				free_irq(pci_irq_vector(fnic->pdev, i),
167 					 fnic->msix[i].devid);
168 		break;
169 
170 	default:
171 		break;
172 	}
173 }
174 
175 int fnic_request_intr(struct fnic *fnic)
176 {
177 	int err = 0;
178 	int i;
179 
180 	switch (vnic_dev_get_intr_mode(fnic->vdev)) {
181 
182 	case VNIC_DEV_INTR_MODE_INTX:
183 		err = request_irq(pci_irq_vector(fnic->pdev, 0),
184 				&fnic_isr_legacy, IRQF_SHARED, DRV_NAME, fnic);
185 		break;
186 
187 	case VNIC_DEV_INTR_MODE_MSI:
188 		err = request_irq(pci_irq_vector(fnic->pdev, 0), &fnic_isr_msi,
189 				  0, fnic->name, fnic);
190 		break;
191 
192 	case VNIC_DEV_INTR_MODE_MSIX:
193 
194 		sprintf(fnic->msix[FNIC_MSIX_RQ].devname,
195 			"%.11s-fcs-rq", fnic->name);
196 		fnic->msix[FNIC_MSIX_RQ].isr = fnic_isr_msix_rq;
197 		fnic->msix[FNIC_MSIX_RQ].devid = fnic;
198 
199 		sprintf(fnic->msix[FNIC_MSIX_WQ].devname,
200 			"%.11s-fcs-wq", fnic->name);
201 		fnic->msix[FNIC_MSIX_WQ].isr = fnic_isr_msix_wq;
202 		fnic->msix[FNIC_MSIX_WQ].devid = fnic;
203 
204 		for (i = fnic->copy_wq_base; i < fnic->wq_copy_count + fnic->copy_wq_base; i++) {
205 			sprintf(fnic->msix[i].devname,
206 				"%.11s-scsi-wq-%d", fnic->name, i-FNIC_MSIX_WQ_COPY);
207 			fnic->msix[i].isr = fnic_isr_msix_wq_copy;
208 			fnic->msix[i].devid = fnic;
209 		}
210 
211 		sprintf(fnic->msix[fnic->err_intr_offset].devname,
212 			"%.11s-err-notify", fnic->name);
213 		fnic->msix[fnic->err_intr_offset].isr =
214 			fnic_isr_msix_err_notify;
215 		fnic->msix[fnic->err_intr_offset].devid = fnic;
216 
217 		for (i = 0; i < fnic->intr_count; i++) {
218 			fnic->msix[i].irq_num = pci_irq_vector(fnic->pdev, i);
219 
220 			err = request_irq(fnic->msix[i].irq_num,
221 							fnic->msix[i].isr, 0,
222 							fnic->msix[i].devname,
223 							fnic->msix[i].devid);
224 			if (err) {
225 				FNIC_ISR_DBG(KERN_ERR, fnic->lport->host, fnic->fnic_num,
226 							"request_irq failed with error: %d\n",
227 							err);
228 				fnic_free_intr(fnic);
229 				break;
230 			}
231 			fnic->msix[i].requested = 1;
232 		}
233 		break;
234 
235 	default:
236 		break;
237 	}
238 
239 	return err;
240 }
241 
242 int fnic_set_intr_mode_msix(struct fnic *fnic)
243 {
244 	unsigned int n = ARRAY_SIZE(fnic->rq);
245 	unsigned int m = ARRAY_SIZE(fnic->wq);
246 	unsigned int o = ARRAY_SIZE(fnic->hw_copy_wq);
247 	unsigned int min_irqs = n + m + 1 + 1; /*rq, raw wq, wq, err*/
248 
249 	/*
250 	 * We need n RQs, m WQs, o Copy WQs, n+m+o CQs, and n+m+o+1 INTRs
251 	 * (last INTR is used for WQ/RQ errors and notification area)
252 	 */
253 	FNIC_ISR_DBG(KERN_INFO, fnic->lport->host, fnic->fnic_num,
254 		"rq-array size: %d wq-array size: %d copy-wq array size: %d\n",
255 		n, m, o);
256 	FNIC_ISR_DBG(KERN_INFO, fnic->lport->host, fnic->fnic_num,
257 		"rq_count: %d raw_wq_count: %d wq_copy_count: %d cq_count: %d\n",
258 		fnic->rq_count, fnic->raw_wq_count,
259 		fnic->wq_copy_count, fnic->cq_count);
260 
261 	if (fnic->rq_count <= n && fnic->raw_wq_count <= m &&
262 		fnic->wq_copy_count <= o) {
263 		int vec_count = 0;
264 		int vecs = fnic->rq_count + fnic->raw_wq_count + fnic->wq_copy_count + 1;
265 
266 		vec_count = pci_alloc_irq_vectors(fnic->pdev, min_irqs, vecs,
267 					PCI_IRQ_MSIX | PCI_IRQ_AFFINITY);
268 		FNIC_ISR_DBG(KERN_INFO, fnic->lport->host, fnic->fnic_num,
269 					"allocated %d MSI-X vectors\n",
270 					vec_count);
271 
272 		if (vec_count > 0) {
273 			if (vec_count < vecs) {
274 				FNIC_ISR_DBG(KERN_ERR, fnic->lport->host, fnic->fnic_num,
275 				"interrupts number mismatch: vec_count: %d vecs: %d\n",
276 				vec_count, vecs);
277 				if (vec_count < min_irqs) {
278 					FNIC_ISR_DBG(KERN_ERR, fnic->lport->host, fnic->fnic_num,
279 								"no interrupts for copy wq\n");
280 					return 1;
281 				}
282 			}
283 
284 			fnic->rq_count = n;
285 			fnic->raw_wq_count = m;
286 			fnic->copy_wq_base = fnic->rq_count + fnic->raw_wq_count;
287 			fnic->wq_copy_count = vec_count - n - m - 1;
288 			fnic->wq_count = fnic->raw_wq_count + fnic->wq_copy_count;
289 			if (fnic->cq_count != vec_count - 1) {
290 				FNIC_ISR_DBG(KERN_ERR, fnic->lport->host, fnic->fnic_num,
291 				"CQ count: %d does not match MSI-X vector count: %d\n",
292 				fnic->cq_count, vec_count);
293 				fnic->cq_count = vec_count - 1;
294 			}
295 			fnic->intr_count = vec_count;
296 			fnic->err_intr_offset = fnic->rq_count + fnic->wq_count;
297 
298 			FNIC_ISR_DBG(KERN_INFO, fnic->lport->host, fnic->fnic_num,
299 				"rq_count: %d raw_wq_count: %d copy_wq_base: %d\n",
300 				fnic->rq_count,
301 				fnic->raw_wq_count, fnic->copy_wq_base);
302 
303 			FNIC_ISR_DBG(KERN_INFO, fnic->lport->host, fnic->fnic_num,
304 				"wq_copy_count: %d wq_count: %d cq_count: %d\n",
305 				fnic->wq_copy_count,
306 				fnic->wq_count, fnic->cq_count);
307 
308 			FNIC_ISR_DBG(KERN_INFO, fnic->lport->host, fnic->fnic_num,
309 				"intr_count: %d err_intr_offset: %u",
310 				fnic->intr_count,
311 				fnic->err_intr_offset);
312 
313 			vnic_dev_set_intr_mode(fnic->vdev, VNIC_DEV_INTR_MODE_MSIX);
314 			FNIC_ISR_DBG(KERN_INFO, fnic->lport->host, fnic->fnic_num,
315 					"fnic using MSI-X\n");
316 			return 0;
317 		}
318 	}
319 	return 1;
320 }
321 
322 int fnic_set_intr_mode(struct fnic *fnic)
323 {
324 	int ret_status = 0;
325 
326 	/*
327 	 * Set interrupt mode (INTx, MSI, MSI-X) depending
328 	 * system capabilities.
329 	 *
330 	 * Try MSI-X first
331 	 */
332 	ret_status = fnic_set_intr_mode_msix(fnic);
333 	if (ret_status == 0)
334 		return ret_status;
335 
336 	/*
337 	 * Next try MSI
338 	 * We need 1 RQ, 1 WQ, 1 WQ_COPY, 3 CQs, and 1 INTR
339 	 */
340 	if (fnic->rq_count >= 1 &&
341 	    fnic->raw_wq_count >= 1 &&
342 	    fnic->wq_copy_count >= 1 &&
343 	    fnic->cq_count >= 3 &&
344 	    fnic->intr_count >= 1 &&
345 	    pci_alloc_irq_vectors(fnic->pdev, 1, 1, PCI_IRQ_MSI) == 1) {
346 		fnic->rq_count = 1;
347 		fnic->raw_wq_count = 1;
348 		fnic->wq_copy_count = 1;
349 		fnic->wq_count = 2;
350 		fnic->cq_count = 3;
351 		fnic->intr_count = 1;
352 		fnic->err_intr_offset = 0;
353 
354 		FNIC_ISR_DBG(KERN_DEBUG, fnic->lport->host, fnic->fnic_num,
355 			     "Using MSI Interrupts\n");
356 		vnic_dev_set_intr_mode(fnic->vdev, VNIC_DEV_INTR_MODE_MSI);
357 
358 		return 0;
359 	}
360 
361 	/*
362 	 * Next try INTx
363 	 * We need 1 RQ, 1 WQ, 1 WQ_COPY, 3 CQs, and 3 INTRs
364 	 * 1 INTR is used for all 3 queues, 1 INTR for queue errors
365 	 * 1 INTR for notification area
366 	 */
367 
368 	if (fnic->rq_count >= 1 &&
369 	    fnic->raw_wq_count >= 1 &&
370 	    fnic->wq_copy_count >= 1 &&
371 	    fnic->cq_count >= 3 &&
372 	    fnic->intr_count >= 3) {
373 
374 		fnic->rq_count = 1;
375 		fnic->raw_wq_count = 1;
376 		fnic->wq_copy_count = 1;
377 		fnic->cq_count = 3;
378 		fnic->intr_count = 3;
379 
380 		FNIC_ISR_DBG(KERN_DEBUG, fnic->lport->host, fnic->fnic_num,
381 			     "Using Legacy Interrupts\n");
382 		vnic_dev_set_intr_mode(fnic->vdev, VNIC_DEV_INTR_MODE_INTX);
383 
384 		return 0;
385 	}
386 
387 	vnic_dev_set_intr_mode(fnic->vdev, VNIC_DEV_INTR_MODE_UNKNOWN);
388 
389 	return -EINVAL;
390 }
391 
392 void fnic_clear_intr_mode(struct fnic *fnic)
393 {
394 	pci_free_irq_vectors(fnic->pdev);
395 	vnic_dev_set_intr_mode(fnic->vdev, VNIC_DEV_INTR_MODE_INTX);
396 }
397