1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Intel(R) Trace Hub driver core
4  *
5  * Copyright (C) 2014-2015 Intel Corporation.
6  */
7 
8 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
9 
10 #include <linux/types.h>
11 #include <linux/module.h>
12 #include <linux/device.h>
13 #include <linux/sysfs.h>
14 #include <linux/kdev_t.h>
15 #include <linux/debugfs.h>
16 #include <linux/idr.h>
17 #include <linux/pci.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/dma-mapping.h>
20 
21 #include "intel_th.h"
22 #include "debug.h"
23 
24 static bool host_mode __read_mostly;
25 module_param(host_mode, bool, 0444);
26 
27 static DEFINE_IDA(intel_th_ida);
28 
29 static int intel_th_match(struct device *dev, struct device_driver *driver)
30 {
31 	struct intel_th_driver *thdrv = to_intel_th_driver(driver);
32 	struct intel_th_device *thdev = to_intel_th_device(dev);
33 
34 	if (thdev->type == INTEL_TH_SWITCH &&
35 	    (!thdrv->enable || !thdrv->disable))
36 		return 0;
37 
38 	return !strcmp(thdev->name, driver->name);
39 }
40 
41 static int intel_th_child_remove(struct device *dev, void *data)
42 {
43 	device_release_driver(dev);
44 
45 	return 0;
46 }
47 
48 static int intel_th_probe(struct device *dev)
49 {
50 	struct intel_th_driver *thdrv = to_intel_th_driver(dev->driver);
51 	struct intel_th_device *thdev = to_intel_th_device(dev);
52 	struct intel_th_driver *hubdrv;
53 	struct intel_th_device *hub = NULL;
54 	int ret;
55 
56 	if (thdev->type == INTEL_TH_SWITCH)
57 		hub = thdev;
58 	else if (dev->parent)
59 		hub = to_intel_th_device(dev->parent);
60 
61 	if (!hub || !hub->dev.driver)
62 		return -EPROBE_DEFER;
63 
64 	hubdrv = to_intel_th_driver(hub->dev.driver);
65 
66 	pm_runtime_set_active(dev);
67 	pm_runtime_no_callbacks(dev);
68 	pm_runtime_enable(dev);
69 
70 	ret = thdrv->probe(to_intel_th_device(dev));
71 	if (ret)
72 		goto out_pm;
73 
74 	if (thdrv->attr_group) {
75 		ret = sysfs_create_group(&thdev->dev.kobj, thdrv->attr_group);
76 		if (ret)
77 			goto out;
78 	}
79 
80 	if (thdev->type == INTEL_TH_OUTPUT &&
81 	    !intel_th_output_assigned(thdev))
82 		/* does not talk to hardware */
83 		ret = hubdrv->assign(hub, thdev);
84 
85 out:
86 	if (ret)
87 		thdrv->remove(thdev);
88 
89 out_pm:
90 	if (ret)
91 		pm_runtime_disable(dev);
92 
93 	return ret;
94 }
95 
96 static void intel_th_device_remove(struct intel_th_device *thdev);
97 
98 static int intel_th_remove(struct device *dev)
99 {
100 	struct intel_th_driver *thdrv = to_intel_th_driver(dev->driver);
101 	struct intel_th_device *thdev = to_intel_th_device(dev);
102 	struct intel_th_device *hub = to_intel_th_hub(thdev);
103 	int err;
104 
105 	if (thdev->type == INTEL_TH_SWITCH) {
106 		struct intel_th *th = to_intel_th(hub);
107 		int i, lowest;
108 
109 		/* disconnect outputs */
110 		err = device_for_each_child(dev, thdev, intel_th_child_remove);
111 		if (err)
112 			return err;
113 
114 		/*
115 		 * Remove outputs, that is, hub's children: they are created
116 		 * at hub's probe time by having the hub call
117 		 * intel_th_output_enable() for each of them.
118 		 */
119 		for (i = 0, lowest = -1; i < th->num_thdevs; i++) {
120 			/*
121 			 * Move the non-output devices from higher up the
122 			 * th->thdev[] array to lower positions to maintain
123 			 * a contiguous array.
124 			 */
125 			if (th->thdev[i]->type != INTEL_TH_OUTPUT) {
126 				if (lowest >= 0) {
127 					th->thdev[lowest] = th->thdev[i];
128 					th->thdev[i] = NULL;
129 					++lowest;
130 				}
131 
132 				continue;
133 			}
134 
135 			if (lowest == -1)
136 				lowest = i;
137 
138 			intel_th_device_remove(th->thdev[i]);
139 			th->thdev[i] = NULL;
140 		}
141 
142 		if (lowest >= 0)
143 			th->num_thdevs = lowest;
144 	}
145 
146 	if (thdrv->attr_group)
147 		sysfs_remove_group(&thdev->dev.kobj, thdrv->attr_group);
148 
149 	pm_runtime_get_sync(dev);
150 
151 	thdrv->remove(thdev);
152 
153 	if (intel_th_output_assigned(thdev)) {
154 		struct intel_th_driver *hubdrv =
155 			to_intel_th_driver(dev->parent->driver);
156 
157 		if (hub->dev.driver)
158 			/* does not talk to hardware */
159 			hubdrv->unassign(hub, thdev);
160 	}
161 
162 	pm_runtime_disable(dev);
163 	pm_runtime_set_active(dev);
164 	pm_runtime_enable(dev);
165 
166 	return 0;
167 }
168 
169 static struct bus_type intel_th_bus = {
170 	.name		= "intel_th",
171 	.match		= intel_th_match,
172 	.probe		= intel_th_probe,
173 	.remove		= intel_th_remove,
174 };
175 
176 static void intel_th_device_free(struct intel_th_device *thdev);
177 
178 static void intel_th_device_release(struct device *dev)
179 {
180 	intel_th_device_free(to_intel_th_device(dev));
181 }
182 
183 static struct device_type intel_th_source_device_type = {
184 	.name		= "intel_th_source_device",
185 	.release	= intel_th_device_release,
186 };
187 
188 static char *intel_th_output_devnode(struct device *dev, umode_t *mode,
189 				     kuid_t *uid, kgid_t *gid)
190 {
191 	struct intel_th_device *thdev = to_intel_th_device(dev);
192 	struct intel_th *th = to_intel_th(thdev);
193 	char *node;
194 
195 	if (thdev->id >= 0)
196 		node = kasprintf(GFP_KERNEL, "intel_th%d/%s%d", th->id,
197 				 thdev->name, thdev->id);
198 	else
199 		node = kasprintf(GFP_KERNEL, "intel_th%d/%s", th->id,
200 				 thdev->name);
201 
202 	return node;
203 }
204 
205 static ssize_t port_show(struct device *dev, struct device_attribute *attr,
206 			 char *buf)
207 {
208 	struct intel_th_device *thdev = to_intel_th_device(dev);
209 
210 	if (thdev->output.port >= 0)
211 		return scnprintf(buf, PAGE_SIZE, "%u\n", thdev->output.port);
212 
213 	return scnprintf(buf, PAGE_SIZE, "unassigned\n");
214 }
215 
216 static DEVICE_ATTR_RO(port);
217 
218 static int intel_th_output_activate(struct intel_th_device *thdev)
219 {
220 	struct intel_th_driver *thdrv =
221 		to_intel_th_driver_or_null(thdev->dev.driver);
222 	struct intel_th *th = to_intel_th(thdev);
223 	int ret = 0;
224 
225 	if (!thdrv)
226 		return -ENODEV;
227 
228 	if (!try_module_get(thdrv->driver.owner))
229 		return -ENODEV;
230 
231 	pm_runtime_get_sync(&thdev->dev);
232 
233 	if (th->activate)
234 		ret = th->activate(th);
235 	if (ret)
236 		goto fail_put;
237 
238 	if (thdrv->activate)
239 		ret = thdrv->activate(thdev);
240 	else
241 		intel_th_trace_enable(thdev);
242 
243 	if (ret)
244 		goto fail_deactivate;
245 
246 	return 0;
247 
248 fail_deactivate:
249 	if (th->deactivate)
250 		th->deactivate(th);
251 
252 fail_put:
253 	pm_runtime_put(&thdev->dev);
254 	module_put(thdrv->driver.owner);
255 
256 	return ret;
257 }
258 
259 static void intel_th_output_deactivate(struct intel_th_device *thdev)
260 {
261 	struct intel_th_driver *thdrv =
262 		to_intel_th_driver_or_null(thdev->dev.driver);
263 	struct intel_th *th = to_intel_th(thdev);
264 
265 	if (!thdrv)
266 		return;
267 
268 	if (thdrv->deactivate)
269 		thdrv->deactivate(thdev);
270 	else
271 		intel_th_trace_disable(thdev);
272 
273 	if (th->deactivate)
274 		th->deactivate(th);
275 
276 	pm_runtime_put(&thdev->dev);
277 	module_put(thdrv->driver.owner);
278 }
279 
280 static ssize_t active_show(struct device *dev, struct device_attribute *attr,
281 			   char *buf)
282 {
283 	struct intel_th_device *thdev = to_intel_th_device(dev);
284 
285 	return scnprintf(buf, PAGE_SIZE, "%d\n", thdev->output.active);
286 }
287 
288 static ssize_t active_store(struct device *dev, struct device_attribute *attr,
289 			    const char *buf, size_t size)
290 {
291 	struct intel_th_device *thdev = to_intel_th_device(dev);
292 	unsigned long val;
293 	int ret;
294 
295 	ret = kstrtoul(buf, 10, &val);
296 	if (ret)
297 		return ret;
298 
299 	if (!!val != thdev->output.active) {
300 		if (val)
301 			ret = intel_th_output_activate(thdev);
302 		else
303 			intel_th_output_deactivate(thdev);
304 	}
305 
306 	return ret ? ret : size;
307 }
308 
309 static DEVICE_ATTR_RW(active);
310 
311 static struct attribute *intel_th_output_attrs[] = {
312 	&dev_attr_port.attr,
313 	&dev_attr_active.attr,
314 	NULL,
315 };
316 
317 ATTRIBUTE_GROUPS(intel_th_output);
318 
319 static struct device_type intel_th_output_device_type = {
320 	.name		= "intel_th_output_device",
321 	.groups		= intel_th_output_groups,
322 	.release	= intel_th_device_release,
323 	.devnode	= intel_th_output_devnode,
324 };
325 
326 static struct device_type intel_th_switch_device_type = {
327 	.name		= "intel_th_switch_device",
328 	.release	= intel_th_device_release,
329 };
330 
331 static struct device_type *intel_th_device_type[] = {
332 	[INTEL_TH_SOURCE]	= &intel_th_source_device_type,
333 	[INTEL_TH_OUTPUT]	= &intel_th_output_device_type,
334 	[INTEL_TH_SWITCH]	= &intel_th_switch_device_type,
335 };
336 
337 int intel_th_driver_register(struct intel_th_driver *thdrv)
338 {
339 	if (!thdrv->probe || !thdrv->remove)
340 		return -EINVAL;
341 
342 	thdrv->driver.bus = &intel_th_bus;
343 
344 	return driver_register(&thdrv->driver);
345 }
346 EXPORT_SYMBOL_GPL(intel_th_driver_register);
347 
348 void intel_th_driver_unregister(struct intel_th_driver *thdrv)
349 {
350 	driver_unregister(&thdrv->driver);
351 }
352 EXPORT_SYMBOL_GPL(intel_th_driver_unregister);
353 
354 static struct intel_th_device *
355 intel_th_device_alloc(struct intel_th *th, unsigned int type, const char *name,
356 		      int id)
357 {
358 	struct device *parent;
359 	struct intel_th_device *thdev;
360 
361 	if (type == INTEL_TH_OUTPUT)
362 		parent = &th->hub->dev;
363 	else
364 		parent = th->dev;
365 
366 	thdev = kzalloc(sizeof(*thdev) + strlen(name) + 1, GFP_KERNEL);
367 	if (!thdev)
368 		return NULL;
369 
370 	thdev->id = id;
371 	thdev->type = type;
372 
373 	strcpy(thdev->name, name);
374 	device_initialize(&thdev->dev);
375 	thdev->dev.bus = &intel_th_bus;
376 	thdev->dev.type = intel_th_device_type[type];
377 	thdev->dev.parent = parent;
378 	thdev->dev.dma_mask = parent->dma_mask;
379 	thdev->dev.dma_parms = parent->dma_parms;
380 	dma_set_coherent_mask(&thdev->dev, parent->coherent_dma_mask);
381 	if (id >= 0)
382 		dev_set_name(&thdev->dev, "%d-%s%d", th->id, name, id);
383 	else
384 		dev_set_name(&thdev->dev, "%d-%s", th->id, name);
385 
386 	return thdev;
387 }
388 
389 static int intel_th_device_add_resources(struct intel_th_device *thdev,
390 					 struct resource *res, int nres)
391 {
392 	struct resource *r;
393 
394 	r = kmemdup(res, sizeof(*res) * nres, GFP_KERNEL);
395 	if (!r)
396 		return -ENOMEM;
397 
398 	thdev->resource = r;
399 	thdev->num_resources = nres;
400 
401 	return 0;
402 }
403 
404 static void intel_th_device_remove(struct intel_th_device *thdev)
405 {
406 	device_del(&thdev->dev);
407 	put_device(&thdev->dev);
408 }
409 
410 static void intel_th_device_free(struct intel_th_device *thdev)
411 {
412 	kfree(thdev->resource);
413 	kfree(thdev);
414 }
415 
416 /*
417  * Intel(R) Trace Hub subdevices
418  */
419 static const struct intel_th_subdevice {
420 	const char		*name;
421 	struct resource		res[3];
422 	unsigned		nres;
423 	unsigned		type;
424 	unsigned		otype;
425 	bool			mknode;
426 	unsigned		scrpd;
427 	int			id;
428 } intel_th_subdevices[] = {
429 	{
430 		.nres	= 1,
431 		.res	= {
432 			{
433 				/* Handle TSCU and CTS from GTH driver */
434 				.start	= REG_GTH_OFFSET,
435 				.end	= REG_CTS_OFFSET + REG_CTS_LENGTH - 1,
436 				.flags	= IORESOURCE_MEM,
437 			},
438 		},
439 		.name	= "gth",
440 		.type	= INTEL_TH_SWITCH,
441 		.id	= -1,
442 	},
443 	{
444 		.nres	= 2,
445 		.res	= {
446 			{
447 				.start	= REG_MSU_OFFSET,
448 				.end	= REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
449 				.flags	= IORESOURCE_MEM,
450 			},
451 			{
452 				.start	= BUF_MSU_OFFSET,
453 				.end	= BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
454 				.flags	= IORESOURCE_MEM,
455 			},
456 		},
457 		.name	= "msc",
458 		.id	= 0,
459 		.type	= INTEL_TH_OUTPUT,
460 		.mknode	= true,
461 		.otype	= GTH_MSU,
462 		.scrpd	= SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC0_IS_ENABLED,
463 	},
464 	{
465 		.nres	= 2,
466 		.res	= {
467 			{
468 				.start	= REG_MSU_OFFSET,
469 				.end	= REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
470 				.flags	= IORESOURCE_MEM,
471 			},
472 			{
473 				.start	= BUF_MSU_OFFSET,
474 				.end	= BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
475 				.flags	= IORESOURCE_MEM,
476 			},
477 		},
478 		.name	= "msc",
479 		.id	= 1,
480 		.type	= INTEL_TH_OUTPUT,
481 		.mknode	= true,
482 		.otype	= GTH_MSU,
483 		.scrpd	= SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC1_IS_ENABLED,
484 	},
485 	{
486 		.nres	= 2,
487 		.res	= {
488 			{
489 				.start	= REG_STH_OFFSET,
490 				.end	= REG_STH_OFFSET + REG_STH_LENGTH - 1,
491 				.flags	= IORESOURCE_MEM,
492 			},
493 			{
494 				.start	= TH_MMIO_SW,
495 				.end	= 0,
496 				.flags	= IORESOURCE_MEM,
497 			},
498 		},
499 		.id	= -1,
500 		.name	= "sth",
501 		.type	= INTEL_TH_SOURCE,
502 	},
503 	{
504 		.nres	= 2,
505 		.res	= {
506 			{
507 				.start	= REG_STH_OFFSET,
508 				.end	= REG_STH_OFFSET + REG_STH_LENGTH - 1,
509 				.flags	= IORESOURCE_MEM,
510 			},
511 			{
512 				.start	= TH_MMIO_RTIT,
513 				.end	= 0,
514 				.flags	= IORESOURCE_MEM,
515 			},
516 		},
517 		.id	= -1,
518 		.name	= "rtit",
519 		.type	= INTEL_TH_SOURCE,
520 	},
521 	{
522 		.nres	= 1,
523 		.res	= {
524 			{
525 				.start	= REG_PTI_OFFSET,
526 				.end	= REG_PTI_OFFSET + REG_PTI_LENGTH - 1,
527 				.flags	= IORESOURCE_MEM,
528 			},
529 		},
530 		.id	= -1,
531 		.name	= "pti",
532 		.type	= INTEL_TH_OUTPUT,
533 		.otype	= GTH_PTI,
534 		.scrpd	= SCRPD_PTI_IS_PRIM_DEST,
535 	},
536 	{
537 		.nres	= 1,
538 		.res	= {
539 			{
540 				.start	= REG_PTI_OFFSET,
541 				.end	= REG_PTI_OFFSET + REG_PTI_LENGTH - 1,
542 				.flags	= IORESOURCE_MEM,
543 			},
544 		},
545 		.id	= -1,
546 		.name	= "lpp",
547 		.type	= INTEL_TH_OUTPUT,
548 		.otype	= GTH_LPP,
549 		.scrpd	= SCRPD_PTI_IS_PRIM_DEST,
550 	},
551 	{
552 		.nres	= 1,
553 		.res	= {
554 			{
555 				.start	= REG_DCIH_OFFSET,
556 				.end	= REG_DCIH_OFFSET + REG_DCIH_LENGTH - 1,
557 				.flags	= IORESOURCE_MEM,
558 			},
559 		},
560 		.id	= -1,
561 		.name	= "dcih",
562 		.type	= INTEL_TH_OUTPUT,
563 	},
564 };
565 
566 #ifdef CONFIG_MODULES
567 static void __intel_th_request_hub_module(struct work_struct *work)
568 {
569 	struct intel_th *th = container_of(work, struct intel_th,
570 					   request_module_work);
571 
572 	request_module("intel_th_%s", th->hub->name);
573 }
574 
575 static int intel_th_request_hub_module(struct intel_th *th)
576 {
577 	INIT_WORK(&th->request_module_work, __intel_th_request_hub_module);
578 	schedule_work(&th->request_module_work);
579 
580 	return 0;
581 }
582 
583 static void intel_th_request_hub_module_flush(struct intel_th *th)
584 {
585 	flush_work(&th->request_module_work);
586 }
587 #else
588 static inline int intel_th_request_hub_module(struct intel_th *th)
589 {
590 	return -EINVAL;
591 }
592 
593 static inline void intel_th_request_hub_module_flush(struct intel_th *th)
594 {
595 }
596 #endif /* CONFIG_MODULES */
597 
598 static struct intel_th_device *
599 intel_th_subdevice_alloc(struct intel_th *th,
600 			 const struct intel_th_subdevice *subdev)
601 {
602 	struct intel_th_device *thdev;
603 	struct resource res[3];
604 	unsigned int req = 0;
605 	int r, err;
606 
607 	thdev = intel_th_device_alloc(th, subdev->type, subdev->name,
608 				      subdev->id);
609 	if (!thdev)
610 		return ERR_PTR(-ENOMEM);
611 
612 	thdev->drvdata = th->drvdata;
613 
614 	memcpy(res, subdev->res,
615 	       sizeof(struct resource) * subdev->nres);
616 
617 	for (r = 0; r < subdev->nres; r++) {
618 		struct resource *devres = th->resource;
619 		int bar = TH_MMIO_CONFIG;
620 
621 		/*
622 		 * Take .end == 0 to mean 'take the whole bar',
623 		 * .start then tells us which bar it is. Default to
624 		 * TH_MMIO_CONFIG.
625 		 */
626 		if (!res[r].end && res[r].flags == IORESOURCE_MEM) {
627 			bar = res[r].start;
628 			err = -ENODEV;
629 			if (bar >= th->num_resources)
630 				goto fail_put_device;
631 			res[r].start = 0;
632 			res[r].end = resource_size(&devres[bar]) - 1;
633 		}
634 
635 		if (res[r].flags & IORESOURCE_MEM) {
636 			res[r].start	+= devres[bar].start;
637 			res[r].end	+= devres[bar].start;
638 
639 			dev_dbg(th->dev, "%s:%d @ %pR\n",
640 				subdev->name, r, &res[r]);
641 		} else if (res[r].flags & IORESOURCE_IRQ) {
642 			/*
643 			 * Only pass on the IRQ if we have useful interrupts:
644 			 * the ones that can be configured via MINTCTL.
645 			 */
646 			if (INTEL_TH_CAP(th, has_mintctl) && th->irq != -1)
647 				res[r].start = th->irq;
648 		}
649 	}
650 
651 	err = intel_th_device_add_resources(thdev, res, subdev->nres);
652 	if (err) {
653 		put_device(&thdev->dev);
654 		goto fail_put_device;
655 	}
656 
657 	if (subdev->type == INTEL_TH_OUTPUT) {
658 		if (subdev->mknode)
659 			thdev->dev.devt = MKDEV(th->major, th->num_thdevs);
660 		thdev->output.type = subdev->otype;
661 		thdev->output.port = -1;
662 		thdev->output.scratchpad = subdev->scrpd;
663 	} else if (subdev->type == INTEL_TH_SWITCH) {
664 		thdev->host_mode =
665 			INTEL_TH_CAP(th, host_mode_only) ? true : host_mode;
666 		th->hub = thdev;
667 	}
668 
669 	err = device_add(&thdev->dev);
670 	if (err) {
671 		put_device(&thdev->dev);
672 		goto fail_free_res;
673 	}
674 
675 	/* need switch driver to be loaded to enumerate the rest */
676 	if (subdev->type == INTEL_TH_SWITCH && !req) {
677 		err = intel_th_request_hub_module(th);
678 		if (!err)
679 			req++;
680 	}
681 
682 	return thdev;
683 
684 fail_free_res:
685 	kfree(thdev->resource);
686 
687 fail_put_device:
688 	put_device(&thdev->dev);
689 
690 	return ERR_PTR(err);
691 }
692 
693 /**
694  * intel_th_output_enable() - find and enable a device for a given output type
695  * @th:		Intel TH instance
696  * @otype:	output type
697  *
698  * Go through the unallocated output devices, find the first one whos type
699  * matches @otype and instantiate it. These devices are removed when the hub
700  * device is removed, see intel_th_remove().
701  */
702 int intel_th_output_enable(struct intel_th *th, unsigned int otype)
703 {
704 	struct intel_th_device *thdev;
705 	int src = 0, dst = 0;
706 
707 	for (src = 0, dst = 0; dst <= th->num_thdevs; src++, dst++) {
708 		for (; src < ARRAY_SIZE(intel_th_subdevices); src++) {
709 			if (intel_th_subdevices[src].type != INTEL_TH_OUTPUT)
710 				continue;
711 
712 			if (intel_th_subdevices[src].otype != otype)
713 				continue;
714 
715 			break;
716 		}
717 
718 		/* no unallocated matching subdevices */
719 		if (src == ARRAY_SIZE(intel_th_subdevices))
720 			return -ENODEV;
721 
722 		for (; dst < th->num_thdevs; dst++) {
723 			if (th->thdev[dst]->type != INTEL_TH_OUTPUT)
724 				continue;
725 
726 			if (th->thdev[dst]->output.type != otype)
727 				continue;
728 
729 			break;
730 		}
731 
732 		/*
733 		 * intel_th_subdevices[src] matches our requirements and is
734 		 * not matched in th::thdev[]
735 		 */
736 		if (dst == th->num_thdevs)
737 			goto found;
738 	}
739 
740 	return -ENODEV;
741 
742 found:
743 	thdev = intel_th_subdevice_alloc(th, &intel_th_subdevices[src]);
744 	if (IS_ERR(thdev))
745 		return PTR_ERR(thdev);
746 
747 	th->thdev[th->num_thdevs++] = thdev;
748 
749 	return 0;
750 }
751 EXPORT_SYMBOL_GPL(intel_th_output_enable);
752 
753 static int intel_th_populate(struct intel_th *th)
754 {
755 	int src;
756 
757 	/* create devices for each intel_th_subdevice */
758 	for (src = 0; src < ARRAY_SIZE(intel_th_subdevices); src++) {
759 		const struct intel_th_subdevice *subdev =
760 			&intel_th_subdevices[src];
761 		struct intel_th_device *thdev;
762 
763 		/* only allow SOURCE and SWITCH devices in host mode */
764 		if ((INTEL_TH_CAP(th, host_mode_only) || host_mode) &&
765 		    subdev->type == INTEL_TH_OUTPUT)
766 			continue;
767 
768 		/*
769 		 * don't enable port OUTPUTs in this path; SWITCH enables them
770 		 * via intel_th_output_enable()
771 		 */
772 		if (subdev->type == INTEL_TH_OUTPUT &&
773 		    subdev->otype != GTH_NONE)
774 			continue;
775 
776 		thdev = intel_th_subdevice_alloc(th, subdev);
777 		/* note: caller should free subdevices from th::thdev[] */
778 		if (IS_ERR(thdev)) {
779 			/* ENODEV for individual subdevices is allowed */
780 			if (PTR_ERR(thdev) == -ENODEV)
781 				continue;
782 
783 			return PTR_ERR(thdev);
784 		}
785 
786 		th->thdev[th->num_thdevs++] = thdev;
787 	}
788 
789 	return 0;
790 }
791 
792 static int match_devt(struct device *dev, void *data)
793 {
794 	dev_t devt = (dev_t)(unsigned long)data;
795 
796 	return dev->devt == devt;
797 }
798 
799 static int intel_th_output_open(struct inode *inode, struct file *file)
800 {
801 	const struct file_operations *fops;
802 	struct intel_th_driver *thdrv;
803 	struct device *dev;
804 	int err;
805 
806 	dev = bus_find_device(&intel_th_bus, NULL,
807 			      (void *)(unsigned long)inode->i_rdev,
808 			      match_devt);
809 	if (!dev || !dev->driver)
810 		return -ENODEV;
811 
812 	thdrv = to_intel_th_driver(dev->driver);
813 	fops = fops_get(thdrv->fops);
814 	if (!fops)
815 		return -ENODEV;
816 
817 	replace_fops(file, fops);
818 
819 	file->private_data = to_intel_th_device(dev);
820 
821 	if (file->f_op->open) {
822 		err = file->f_op->open(inode, file);
823 		return err;
824 	}
825 
826 	return 0;
827 }
828 
829 static const struct file_operations intel_th_output_fops = {
830 	.open	= intel_th_output_open,
831 	.llseek	= noop_llseek,
832 };
833 
834 static irqreturn_t intel_th_irq(int irq, void *data)
835 {
836 	struct intel_th *th = data;
837 	irqreturn_t ret = IRQ_NONE;
838 	struct intel_th_driver *d;
839 	int i;
840 
841 	for (i = 0; i < th->num_thdevs; i++) {
842 		if (th->thdev[i]->type != INTEL_TH_OUTPUT)
843 			continue;
844 
845 		d = to_intel_th_driver(th->thdev[i]->dev.driver);
846 		if (d && d->irq)
847 			ret |= d->irq(th->thdev[i]);
848 	}
849 
850 	if (ret == IRQ_NONE)
851 		pr_warn_ratelimited("nobody cared for irq\n");
852 
853 	return ret;
854 }
855 
856 /**
857  * intel_th_alloc() - allocate a new Intel TH device and its subdevices
858  * @dev:	parent device
859  * @devres:	resources indexed by th_mmio_idx
860  * @irq:	irq number
861  */
862 struct intel_th *
863 intel_th_alloc(struct device *dev, struct intel_th_drvdata *drvdata,
864 	       struct resource *devres, unsigned int ndevres)
865 {
866 	int err, r, nr_mmios = 0;
867 	struct intel_th *th;
868 
869 	th = kzalloc(sizeof(*th), GFP_KERNEL);
870 	if (!th)
871 		return ERR_PTR(-ENOMEM);
872 
873 	th->id = ida_simple_get(&intel_th_ida, 0, 0, GFP_KERNEL);
874 	if (th->id < 0) {
875 		err = th->id;
876 		goto err_alloc;
877 	}
878 
879 	th->major = __register_chrdev(0, 0, TH_POSSIBLE_OUTPUTS,
880 				      "intel_th/output", &intel_th_output_fops);
881 	if (th->major < 0) {
882 		err = th->major;
883 		goto err_ida;
884 	}
885 	th->irq = -1;
886 	th->dev = dev;
887 	th->drvdata = drvdata;
888 
889 	for (r = 0; r < ndevres; r++)
890 		switch (devres[r].flags & IORESOURCE_TYPE_BITS) {
891 		case IORESOURCE_MEM:
892 			th->resource[nr_mmios++] = devres[r];
893 			break;
894 		case IORESOURCE_IRQ:
895 			err = devm_request_irq(dev, devres[r].start,
896 					       intel_th_irq, IRQF_SHARED,
897 					       dev_name(dev), th);
898 			if (err)
899 				goto err_chrdev;
900 
901 			if (th->irq == -1)
902 				th->irq = devres[r].start;
903 			break;
904 		default:
905 			dev_warn(dev, "Unknown resource type %lx\n",
906 				 devres[r].flags);
907 			break;
908 		}
909 
910 	th->num_resources = nr_mmios;
911 
912 	dev_set_drvdata(dev, th);
913 
914 	pm_runtime_no_callbacks(dev);
915 	pm_runtime_put(dev);
916 	pm_runtime_allow(dev);
917 
918 	err = intel_th_populate(th);
919 	if (err) {
920 		/* free the subdevices and undo everything */
921 		intel_th_free(th);
922 		return ERR_PTR(err);
923 	}
924 
925 	return th;
926 
927 err_chrdev:
928 	__unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
929 			    "intel_th/output");
930 
931 err_ida:
932 	ida_simple_remove(&intel_th_ida, th->id);
933 
934 err_alloc:
935 	kfree(th);
936 
937 	return ERR_PTR(err);
938 }
939 EXPORT_SYMBOL_GPL(intel_th_alloc);
940 
941 void intel_th_free(struct intel_th *th)
942 {
943 	int i;
944 
945 	intel_th_request_hub_module_flush(th);
946 
947 	intel_th_device_remove(th->hub);
948 	for (i = 0; i < th->num_thdevs; i++) {
949 		if (th->thdev[i] != th->hub)
950 			intel_th_device_remove(th->thdev[i]);
951 		th->thdev[i] = NULL;
952 	}
953 
954 	th->num_thdevs = 0;
955 
956 	pm_runtime_get_sync(th->dev);
957 	pm_runtime_forbid(th->dev);
958 
959 	__unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
960 			    "intel_th/output");
961 
962 	ida_simple_remove(&intel_th_ida, th->id);
963 
964 	kfree(th);
965 }
966 EXPORT_SYMBOL_GPL(intel_th_free);
967 
968 /**
969  * intel_th_trace_enable() - enable tracing for an output device
970  * @thdev:	output device that requests tracing be enabled
971  */
972 int intel_th_trace_enable(struct intel_th_device *thdev)
973 {
974 	struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
975 	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
976 
977 	if (WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH))
978 		return -EINVAL;
979 
980 	if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
981 		return -EINVAL;
982 
983 	pm_runtime_get_sync(&thdev->dev);
984 	hubdrv->enable(hub, &thdev->output);
985 
986 	return 0;
987 }
988 EXPORT_SYMBOL_GPL(intel_th_trace_enable);
989 
990 /**
991  * intel_th_trace_switch() - execute a switch sequence
992  * @thdev:	output device that requests tracing switch
993  */
994 int intel_th_trace_switch(struct intel_th_device *thdev)
995 {
996 	struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
997 	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
998 
999 	if (WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH))
1000 		return -EINVAL;
1001 
1002 	if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
1003 		return -EINVAL;
1004 
1005 	hubdrv->trig_switch(hub, &thdev->output);
1006 
1007 	return 0;
1008 }
1009 EXPORT_SYMBOL_GPL(intel_th_trace_switch);
1010 
1011 /**
1012  * intel_th_trace_disable() - disable tracing for an output device
1013  * @thdev:	output device that requests tracing be disabled
1014  */
1015 int intel_th_trace_disable(struct intel_th_device *thdev)
1016 {
1017 	struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
1018 	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
1019 
1020 	WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH);
1021 	if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
1022 		return -EINVAL;
1023 
1024 	hubdrv->disable(hub, &thdev->output);
1025 	pm_runtime_put(&thdev->dev);
1026 
1027 	return 0;
1028 }
1029 EXPORT_SYMBOL_GPL(intel_th_trace_disable);
1030 
1031 int intel_th_set_output(struct intel_th_device *thdev,
1032 			unsigned int master)
1033 {
1034 	struct intel_th_device *hub = to_intel_th_hub(thdev);
1035 	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
1036 
1037 	/* In host mode, this is up to the external debugger, do nothing. */
1038 	if (hub->host_mode)
1039 		return 0;
1040 
1041 	if (!hubdrv->set_output)
1042 		return -ENOTSUPP;
1043 
1044 	return hubdrv->set_output(hub, master);
1045 }
1046 EXPORT_SYMBOL_GPL(intel_th_set_output);
1047 
1048 static int __init intel_th_init(void)
1049 {
1050 	intel_th_debug_init();
1051 
1052 	return bus_register(&intel_th_bus);
1053 }
1054 subsys_initcall(intel_th_init);
1055 
1056 static void __exit intel_th_exit(void)
1057 {
1058 	intel_th_debug_done();
1059 
1060 	bus_unregister(&intel_th_bus);
1061 }
1062 module_exit(intel_th_exit);
1063 
1064 MODULE_LICENSE("GPL v2");
1065 MODULE_DESCRIPTION("Intel(R) Trace Hub controller driver");
1066 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
1067