xref: /linux/drivers/misc/ocxl/pci.c (revision 856e7c4b619af622d56b3b454f7bec32a170ac99)
1 // SPDX-License-Identifier: GPL-2.0+
2 // Copyright 2017 IBM Corp.
3 #include <linux/module.h>
4 #include <linux/pci.h>
5 #include <linux/idr.h>
6 #include <asm/pnv-ocxl.h>
7 #include "ocxl_internal.h"
8 
9 /*
10  * Any opencapi device which wants to use this 'generic' driver should
11  * use the 0x062B device ID. Vendors should define the subsystem
12  * vendor/device ID to help differentiate devices.
13  */
14 static const struct pci_device_id ocxl_pci_tbl[] = {
15 	{ PCI_DEVICE(PCI_VENDOR_ID_IBM, 0x062B), },
16 	{ }
17 };
18 MODULE_DEVICE_TABLE(pci, ocxl_pci_tbl);
19 
20 
21 static struct ocxl_fn *ocxl_fn_get(struct ocxl_fn *fn)
22 {
23 	return (get_device(&fn->dev) == NULL) ? NULL : fn;
24 }
25 
26 static void ocxl_fn_put(struct ocxl_fn *fn)
27 {
28 	put_device(&fn->dev);
29 }
30 
31 struct ocxl_afu *ocxl_afu_get(struct ocxl_afu *afu)
32 {
33 	return (get_device(&afu->dev) == NULL) ? NULL : afu;
34 }
35 
36 void ocxl_afu_put(struct ocxl_afu *afu)
37 {
38 	put_device(&afu->dev);
39 }
40 
41 static struct ocxl_afu *alloc_afu(struct ocxl_fn *fn)
42 {
43 	struct ocxl_afu *afu;
44 
45 	afu = kzalloc(sizeof(struct ocxl_afu), GFP_KERNEL);
46 	if (!afu)
47 		return NULL;
48 
49 	mutex_init(&afu->contexts_lock);
50 	mutex_init(&afu->afu_control_lock);
51 	idr_init(&afu->contexts_idr);
52 	afu->fn = fn;
53 	ocxl_fn_get(fn);
54 	return afu;
55 }
56 
57 static void free_afu(struct ocxl_afu *afu)
58 {
59 	idr_destroy(&afu->contexts_idr);
60 	ocxl_fn_put(afu->fn);
61 	kfree(afu);
62 }
63 
64 static void free_afu_dev(struct device *dev)
65 {
66 	struct ocxl_afu *afu = to_ocxl_afu(dev);
67 
68 	ocxl_unregister_afu(afu);
69 	free_afu(afu);
70 }
71 
72 static int set_afu_device(struct ocxl_afu *afu, const char *location)
73 {
74 	struct ocxl_fn *fn = afu->fn;
75 	int rc;
76 
77 	afu->dev.parent = &fn->dev;
78 	afu->dev.release = free_afu_dev;
79 	rc = dev_set_name(&afu->dev, "%s.%s.%hhu", afu->config.name, location,
80 		afu->config.idx);
81 	return rc;
82 }
83 
84 static int assign_afu_actag(struct ocxl_afu *afu, struct pci_dev *dev)
85 {
86 	struct ocxl_fn *fn = afu->fn;
87 	int actag_count, actag_offset;
88 
89 	/*
90 	 * if there were not enough actags for the function, each afu
91 	 * reduces its count as well
92 	 */
93 	actag_count = afu->config.actag_supported *
94 		fn->actag_enabled / fn->actag_supported;
95 	actag_offset = ocxl_actag_afu_alloc(fn, actag_count);
96 	if (actag_offset < 0) {
97 		dev_err(&afu->dev, "Can't allocate %d actags for AFU: %d\n",
98 			actag_count, actag_offset);
99 		return actag_offset;
100 	}
101 	afu->actag_base = fn->actag_base + actag_offset;
102 	afu->actag_enabled = actag_count;
103 
104 	ocxl_config_set_afu_actag(dev, afu->config.dvsec_afu_control_pos,
105 				afu->actag_base, afu->actag_enabled);
106 	dev_dbg(&afu->dev, "actag base=%d enabled=%d\n",
107 		afu->actag_base, afu->actag_enabled);
108 	return 0;
109 }
110 
111 static void reclaim_afu_actag(struct ocxl_afu *afu)
112 {
113 	struct ocxl_fn *fn = afu->fn;
114 	int start_offset, size;
115 
116 	start_offset = afu->actag_base - fn->actag_base;
117 	size = afu->actag_enabled;
118 	ocxl_actag_afu_free(afu->fn, start_offset, size);
119 }
120 
121 static int assign_afu_pasid(struct ocxl_afu *afu, struct pci_dev *dev)
122 {
123 	struct ocxl_fn *fn = afu->fn;
124 	int pasid_count, pasid_offset;
125 
126 	/*
127 	 * We only support the case where the function configuration
128 	 * requested enough PASIDs to cover all AFUs.
129 	 */
130 	pasid_count = 1 << afu->config.pasid_supported_log;
131 	pasid_offset = ocxl_pasid_afu_alloc(fn, pasid_count);
132 	if (pasid_offset < 0) {
133 		dev_err(&afu->dev, "Can't allocate %d PASIDs for AFU: %d\n",
134 			pasid_count, pasid_offset);
135 		return pasid_offset;
136 	}
137 	afu->pasid_base = fn->pasid_base + pasid_offset;
138 	afu->pasid_count = 0;
139 	afu->pasid_max = pasid_count;
140 
141 	ocxl_config_set_afu_pasid(dev, afu->config.dvsec_afu_control_pos,
142 				afu->pasid_base,
143 				afu->config.pasid_supported_log);
144 	dev_dbg(&afu->dev, "PASID base=%d, enabled=%d\n",
145 		afu->pasid_base, pasid_count);
146 	return 0;
147 }
148 
149 static void reclaim_afu_pasid(struct ocxl_afu *afu)
150 {
151 	struct ocxl_fn *fn = afu->fn;
152 	int start_offset, size;
153 
154 	start_offset = afu->pasid_base - fn->pasid_base;
155 	size = 1 << afu->config.pasid_supported_log;
156 	ocxl_pasid_afu_free(afu->fn, start_offset, size);
157 }
158 
159 static int reserve_fn_bar(struct ocxl_fn *fn, int bar)
160 {
161 	struct pci_dev *dev = to_pci_dev(fn->dev.parent);
162 	int rc, idx;
163 
164 	if (bar != 0 && bar != 2 && bar != 4)
165 		return -EINVAL;
166 
167 	idx = bar >> 1;
168 	if (fn->bar_used[idx]++ == 0) {
169 		rc = pci_request_region(dev, bar, "ocxl");
170 		if (rc)
171 			return rc;
172 	}
173 	return 0;
174 }
175 
176 static void release_fn_bar(struct ocxl_fn *fn, int bar)
177 {
178 	struct pci_dev *dev = to_pci_dev(fn->dev.parent);
179 	int idx;
180 
181 	if (bar != 0 && bar != 2 && bar != 4)
182 		return;
183 
184 	idx = bar >> 1;
185 	if (--fn->bar_used[idx] == 0)
186 		pci_release_region(dev, bar);
187 	WARN_ON(fn->bar_used[idx] < 0);
188 }
189 
190 static int map_mmio_areas(struct ocxl_afu *afu, struct pci_dev *dev)
191 {
192 	int rc;
193 
194 	rc = reserve_fn_bar(afu->fn, afu->config.global_mmio_bar);
195 	if (rc)
196 		return rc;
197 
198 	rc = reserve_fn_bar(afu->fn, afu->config.pp_mmio_bar);
199 	if (rc) {
200 		release_fn_bar(afu->fn, afu->config.global_mmio_bar);
201 		return rc;
202 	}
203 
204 	afu->global_mmio_start =
205 		pci_resource_start(dev, afu->config.global_mmio_bar) +
206 		afu->config.global_mmio_offset;
207 	afu->pp_mmio_start =
208 		pci_resource_start(dev, afu->config.pp_mmio_bar) +
209 		afu->config.pp_mmio_offset;
210 
211 	afu->global_mmio_ptr = ioremap(afu->global_mmio_start,
212 				afu->config.global_mmio_size);
213 	if (!afu->global_mmio_ptr) {
214 		release_fn_bar(afu->fn, afu->config.pp_mmio_bar);
215 		release_fn_bar(afu->fn, afu->config.global_mmio_bar);
216 		dev_err(&dev->dev, "Error mapping global mmio area\n");
217 		return -ENOMEM;
218 	}
219 
220 	/*
221 	 * Leave an empty page between the per-process mmio area and
222 	 * the AFU interrupt mappings
223 	 */
224 	afu->irq_base_offset = afu->config.pp_mmio_stride + PAGE_SIZE;
225 	return 0;
226 }
227 
228 static void unmap_mmio_areas(struct ocxl_afu *afu)
229 {
230 	if (afu->global_mmio_ptr) {
231 		iounmap(afu->global_mmio_ptr);
232 		afu->global_mmio_ptr = NULL;
233 	}
234 	afu->global_mmio_start = 0;
235 	afu->pp_mmio_start = 0;
236 	release_fn_bar(afu->fn, afu->config.pp_mmio_bar);
237 	release_fn_bar(afu->fn, afu->config.global_mmio_bar);
238 }
239 
240 static int configure_afu(struct ocxl_afu *afu, u8 afu_idx, struct pci_dev *dev)
241 {
242 	int rc;
243 
244 	rc = ocxl_config_read_afu(dev, &afu->fn->config, &afu->config, afu_idx);
245 	if (rc)
246 		return rc;
247 
248 	rc = set_afu_device(afu, dev_name(&dev->dev));
249 	if (rc)
250 		return rc;
251 
252 	rc = assign_afu_actag(afu, dev);
253 	if (rc)
254 		return rc;
255 
256 	rc = assign_afu_pasid(afu, dev);
257 	if (rc) {
258 		reclaim_afu_actag(afu);
259 		return rc;
260 	}
261 
262 	rc = map_mmio_areas(afu, dev);
263 	if (rc) {
264 		reclaim_afu_pasid(afu);
265 		reclaim_afu_actag(afu);
266 		return rc;
267 	}
268 	return 0;
269 }
270 
271 static void deconfigure_afu(struct ocxl_afu *afu)
272 {
273 	unmap_mmio_areas(afu);
274 	reclaim_afu_pasid(afu);
275 	reclaim_afu_actag(afu);
276 }
277 
278 static int activate_afu(struct pci_dev *dev, struct ocxl_afu *afu)
279 {
280 	int rc;
281 
282 	ocxl_config_set_afu_state(dev, afu->config.dvsec_afu_control_pos, 1);
283 	/*
284 	 * Char device creation is the last step, as processes can
285 	 * call our driver immediately, so all our inits must be finished.
286 	 */
287 	rc = ocxl_create_cdev(afu);
288 	if (rc)
289 		return rc;
290 	return 0;
291 }
292 
293 static void deactivate_afu(struct ocxl_afu *afu)
294 {
295 	struct pci_dev *dev = to_pci_dev(afu->fn->dev.parent);
296 
297 	ocxl_destroy_cdev(afu);
298 	ocxl_config_set_afu_state(dev, afu->config.dvsec_afu_control_pos, 0);
299 }
300 
301 static int init_afu(struct pci_dev *dev, struct ocxl_fn *fn, u8 afu_idx)
302 {
303 	int rc;
304 	struct ocxl_afu *afu;
305 
306 	afu = alloc_afu(fn);
307 	if (!afu)
308 		return -ENOMEM;
309 
310 	rc = configure_afu(afu, afu_idx, dev);
311 	if (rc) {
312 		free_afu(afu);
313 		return rc;
314 	}
315 
316 	rc = ocxl_register_afu(afu);
317 	if (rc)
318 		goto err;
319 
320 	rc = ocxl_sysfs_add_afu(afu);
321 	if (rc)
322 		goto err;
323 
324 	rc = activate_afu(dev, afu);
325 	if (rc)
326 		goto err_sys;
327 
328 	list_add_tail(&afu->list, &fn->afu_list);
329 	return 0;
330 
331 err_sys:
332 	ocxl_sysfs_remove_afu(afu);
333 err:
334 	deconfigure_afu(afu);
335 	device_unregister(&afu->dev);
336 	return rc;
337 }
338 
339 static void remove_afu(struct ocxl_afu *afu)
340 {
341 	list_del(&afu->list);
342 	ocxl_context_detach_all(afu);
343 	deactivate_afu(afu);
344 	ocxl_sysfs_remove_afu(afu);
345 	deconfigure_afu(afu);
346 	device_unregister(&afu->dev);
347 }
348 
349 static struct ocxl_fn *alloc_function(struct pci_dev *dev)
350 {
351 	struct ocxl_fn *fn;
352 
353 	fn = kzalloc(sizeof(struct ocxl_fn), GFP_KERNEL);
354 	if (!fn)
355 		return NULL;
356 
357 	INIT_LIST_HEAD(&fn->afu_list);
358 	INIT_LIST_HEAD(&fn->pasid_list);
359 	INIT_LIST_HEAD(&fn->actag_list);
360 	return fn;
361 }
362 
363 static void free_function(struct ocxl_fn *fn)
364 {
365 	WARN_ON(!list_empty(&fn->afu_list));
366 	WARN_ON(!list_empty(&fn->pasid_list));
367 	kfree(fn);
368 }
369 
370 static void free_function_dev(struct device *dev)
371 {
372 	struct ocxl_fn *fn = to_ocxl_function(dev);
373 
374 	free_function(fn);
375 }
376 
377 static int set_function_device(struct ocxl_fn *fn, struct pci_dev *dev)
378 {
379 	int rc;
380 
381 	fn->dev.parent = &dev->dev;
382 	fn->dev.release = free_function_dev;
383 	rc = dev_set_name(&fn->dev, "ocxlfn.%s", dev_name(&dev->dev));
384 	if (rc)
385 		return rc;
386 	pci_set_drvdata(dev, fn);
387 	return 0;
388 }
389 
390 static int assign_function_actag(struct ocxl_fn *fn)
391 {
392 	struct pci_dev *dev = to_pci_dev(fn->dev.parent);
393 	u16 base, enabled, supported;
394 	int rc;
395 
396 	rc = ocxl_config_get_actag_info(dev, &base, &enabled, &supported);
397 	if (rc)
398 		return rc;
399 
400 	fn->actag_base = base;
401 	fn->actag_enabled = enabled;
402 	fn->actag_supported = supported;
403 
404 	ocxl_config_set_actag(dev, fn->config.dvsec_function_pos,
405 			fn->actag_base,	fn->actag_enabled);
406 	dev_dbg(&fn->dev, "actag range starting at %d, enabled %d\n",
407 		fn->actag_base, fn->actag_enabled);
408 	return 0;
409 }
410 
411 static int set_function_pasid(struct ocxl_fn *fn)
412 {
413 	struct pci_dev *dev = to_pci_dev(fn->dev.parent);
414 	int rc, desired_count, max_count;
415 
416 	/* A function may not require any PASID */
417 	if (fn->config.max_pasid_log < 0)
418 		return 0;
419 
420 	rc = ocxl_config_get_pasid_info(dev, &max_count);
421 	if (rc)
422 		return rc;
423 
424 	desired_count = 1 << fn->config.max_pasid_log;
425 
426 	if (desired_count > max_count) {
427 		dev_err(&fn->dev,
428 			"Function requires more PASIDs than is available (%d vs. %d)\n",
429 			desired_count, max_count);
430 		return -ENOSPC;
431 	}
432 
433 	fn->pasid_base = 0;
434 	return 0;
435 }
436 
437 static int configure_function(struct ocxl_fn *fn, struct pci_dev *dev)
438 {
439 	int rc;
440 
441 	rc = pci_enable_device(dev);
442 	if (rc) {
443 		dev_err(&dev->dev, "pci_enable_device failed: %d\n", rc);
444 		return rc;
445 	}
446 
447 	/*
448 	 * Once it has been confirmed to work on our hardware, we
449 	 * should reset the function, to force the adapter to restart
450 	 * from scratch.
451 	 * A function reset would also reset all its AFUs.
452 	 *
453 	 * Some hints for implementation:
454 	 *
455 	 * - there's not status bit to know when the reset is done. We
456 	 *   should try reading the config space to know when it's
457 	 *   done.
458 	 * - probably something like:
459 	 *	Reset
460 	 *	wait 100ms
461 	 *	issue config read
462 	 *	allow device up to 1 sec to return success on config
463 	 *	read before declaring it broken
464 	 *
465 	 * Some shared logic on the card (CFG, TLX) won't be reset, so
466 	 * there's no guarantee that it will be enough.
467 	 */
468 	rc = ocxl_config_read_function(dev, &fn->config);
469 	if (rc)
470 		return rc;
471 
472 	rc = set_function_device(fn, dev);
473 	if (rc)
474 		return rc;
475 
476 	rc = assign_function_actag(fn);
477 	if (rc)
478 		return rc;
479 
480 	rc = set_function_pasid(fn);
481 	if (rc)
482 		return rc;
483 
484 	rc = ocxl_link_setup(dev, 0, &fn->link);
485 	if (rc)
486 		return rc;
487 
488 	rc = ocxl_config_set_TL(dev, fn->config.dvsec_tl_pos);
489 	if (rc) {
490 		ocxl_link_release(dev, fn->link);
491 		return rc;
492 	}
493 	return 0;
494 }
495 
496 static void deconfigure_function(struct ocxl_fn *fn)
497 {
498 	struct pci_dev *dev = to_pci_dev(fn->dev.parent);
499 
500 	ocxl_link_release(dev, fn->link);
501 	pci_disable_device(dev);
502 }
503 
504 static struct ocxl_fn *init_function(struct pci_dev *dev)
505 {
506 	struct ocxl_fn *fn;
507 	int rc;
508 
509 	fn = alloc_function(dev);
510 	if (!fn)
511 		return ERR_PTR(-ENOMEM);
512 
513 	rc = configure_function(fn, dev);
514 	if (rc) {
515 		free_function(fn);
516 		return ERR_PTR(rc);
517 	}
518 
519 	rc = device_register(&fn->dev);
520 	if (rc) {
521 		deconfigure_function(fn);
522 		put_device(&fn->dev);
523 		return ERR_PTR(rc);
524 	}
525 	return fn;
526 }
527 
528 static void remove_function(struct ocxl_fn *fn)
529 {
530 	deconfigure_function(fn);
531 	device_unregister(&fn->dev);
532 }
533 
534 static int ocxl_probe(struct pci_dev *dev, const struct pci_device_id *id)
535 {
536 	int rc, afu_count = 0;
537 	u8 afu;
538 	struct ocxl_fn *fn;
539 
540 	if (!radix_enabled()) {
541 		dev_err(&dev->dev, "Unsupported memory model (hash)\n");
542 		return -ENODEV;
543 	}
544 
545 	fn = init_function(dev);
546 	if (IS_ERR(fn)) {
547 		dev_err(&dev->dev, "function init failed: %li\n",
548 			PTR_ERR(fn));
549 		return PTR_ERR(fn);
550 	}
551 
552 	for (afu = 0; afu <= fn->config.max_afu_index; afu++) {
553 		rc = ocxl_config_check_afu_index(dev, &fn->config, afu);
554 		if (rc > 0) {
555 			rc = init_afu(dev, fn, afu);
556 			if (rc) {
557 				dev_err(&dev->dev,
558 					"Can't initialize AFU index %d\n", afu);
559 				continue;
560 			}
561 			afu_count++;
562 		}
563 	}
564 	dev_info(&dev->dev, "%d AFU(s) configured\n", afu_count);
565 	return 0;
566 }
567 
568 static void ocxl_remove(struct pci_dev *dev)
569 {
570 	struct ocxl_afu *afu, *tmp;
571 	struct ocxl_fn *fn = pci_get_drvdata(dev);
572 
573 	list_for_each_entry_safe(afu, tmp, &fn->afu_list, list) {
574 		remove_afu(afu);
575 	}
576 	remove_function(fn);
577 }
578 
579 struct pci_driver ocxl_pci_driver = {
580 	.name = "ocxl",
581 	.id_table = ocxl_pci_tbl,
582 	.probe = ocxl_probe,
583 	.remove = ocxl_remove,
584 	.shutdown = ocxl_remove,
585 };
586