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 		goto fail_put_device;
654 
655 	if (subdev->type == INTEL_TH_OUTPUT) {
656 		if (subdev->mknode)
657 			thdev->dev.devt = MKDEV(th->major, th->num_thdevs);
658 		thdev->output.type = subdev->otype;
659 		thdev->output.port = -1;
660 		thdev->output.scratchpad = subdev->scrpd;
661 	} else if (subdev->type == INTEL_TH_SWITCH) {
662 		thdev->host_mode =
663 			INTEL_TH_CAP(th, host_mode_only) ? true : host_mode;
664 		th->hub = thdev;
665 	}
666 
667 	err = device_add(&thdev->dev);
668 	if (err)
669 		goto fail_free_res;
670 
671 	/* need switch driver to be loaded to enumerate the rest */
672 	if (subdev->type == INTEL_TH_SWITCH && !req) {
673 		err = intel_th_request_hub_module(th);
674 		if (!err)
675 			req++;
676 	}
677 
678 	return thdev;
679 
680 fail_free_res:
681 	kfree(thdev->resource);
682 
683 fail_put_device:
684 	put_device(&thdev->dev);
685 
686 	return ERR_PTR(err);
687 }
688 
689 /**
690  * intel_th_output_enable() - find and enable a device for a given output type
691  * @th:		Intel TH instance
692  * @otype:	output type
693  *
694  * Go through the unallocated output devices, find the first one whos type
695  * matches @otype and instantiate it. These devices are removed when the hub
696  * device is removed, see intel_th_remove().
697  */
698 int intel_th_output_enable(struct intel_th *th, unsigned int otype)
699 {
700 	struct intel_th_device *thdev;
701 	int src = 0, dst = 0;
702 
703 	for (src = 0, dst = 0; dst <= th->num_thdevs; src++, dst++) {
704 		for (; src < ARRAY_SIZE(intel_th_subdevices); src++) {
705 			if (intel_th_subdevices[src].type != INTEL_TH_OUTPUT)
706 				continue;
707 
708 			if (intel_th_subdevices[src].otype != otype)
709 				continue;
710 
711 			break;
712 		}
713 
714 		/* no unallocated matching subdevices */
715 		if (src == ARRAY_SIZE(intel_th_subdevices))
716 			return -ENODEV;
717 
718 		for (; dst < th->num_thdevs; dst++) {
719 			if (th->thdev[dst]->type != INTEL_TH_OUTPUT)
720 				continue;
721 
722 			if (th->thdev[dst]->output.type != otype)
723 				continue;
724 
725 			break;
726 		}
727 
728 		/*
729 		 * intel_th_subdevices[src] matches our requirements and is
730 		 * not matched in th::thdev[]
731 		 */
732 		if (dst == th->num_thdevs)
733 			goto found;
734 	}
735 
736 	return -ENODEV;
737 
738 found:
739 	thdev = intel_th_subdevice_alloc(th, &intel_th_subdevices[src]);
740 	if (IS_ERR(thdev))
741 		return PTR_ERR(thdev);
742 
743 	th->thdev[th->num_thdevs++] = thdev;
744 
745 	return 0;
746 }
747 EXPORT_SYMBOL_GPL(intel_th_output_enable);
748 
749 static int intel_th_populate(struct intel_th *th)
750 {
751 	int src;
752 
753 	/* create devices for each intel_th_subdevice */
754 	for (src = 0; src < ARRAY_SIZE(intel_th_subdevices); src++) {
755 		const struct intel_th_subdevice *subdev =
756 			&intel_th_subdevices[src];
757 		struct intel_th_device *thdev;
758 
759 		/* only allow SOURCE and SWITCH devices in host mode */
760 		if ((INTEL_TH_CAP(th, host_mode_only) || host_mode) &&
761 		    subdev->type == INTEL_TH_OUTPUT)
762 			continue;
763 
764 		/*
765 		 * don't enable port OUTPUTs in this path; SWITCH enables them
766 		 * via intel_th_output_enable()
767 		 */
768 		if (subdev->type == INTEL_TH_OUTPUT &&
769 		    subdev->otype != GTH_NONE)
770 			continue;
771 
772 		thdev = intel_th_subdevice_alloc(th, subdev);
773 		/* note: caller should free subdevices from th::thdev[] */
774 		if (IS_ERR(thdev)) {
775 			/* ENODEV for individual subdevices is allowed */
776 			if (PTR_ERR(thdev) == -ENODEV)
777 				continue;
778 
779 			return PTR_ERR(thdev);
780 		}
781 
782 		th->thdev[th->num_thdevs++] = thdev;
783 	}
784 
785 	return 0;
786 }
787 
788 static int intel_th_output_open(struct inode *inode, struct file *file)
789 {
790 	const struct file_operations *fops;
791 	struct intel_th_driver *thdrv;
792 	struct device *dev;
793 	int err;
794 
795 	dev = bus_find_device_by_devt(&intel_th_bus, inode->i_rdev);
796 	if (!dev || !dev->driver)
797 		return -ENODEV;
798 
799 	thdrv = to_intel_th_driver(dev->driver);
800 	fops = fops_get(thdrv->fops);
801 	if (!fops)
802 		return -ENODEV;
803 
804 	replace_fops(file, fops);
805 
806 	file->private_data = to_intel_th_device(dev);
807 
808 	if (file->f_op->open) {
809 		err = file->f_op->open(inode, file);
810 		return err;
811 	}
812 
813 	return 0;
814 }
815 
816 static const struct file_operations intel_th_output_fops = {
817 	.open	= intel_th_output_open,
818 	.llseek	= noop_llseek,
819 };
820 
821 static irqreturn_t intel_th_irq(int irq, void *data)
822 {
823 	struct intel_th *th = data;
824 	irqreturn_t ret = IRQ_NONE;
825 	struct intel_th_driver *d;
826 	int i;
827 
828 	for (i = 0; i < th->num_thdevs; i++) {
829 		if (th->thdev[i]->type != INTEL_TH_OUTPUT)
830 			continue;
831 
832 		d = to_intel_th_driver(th->thdev[i]->dev.driver);
833 		if (d && d->irq)
834 			ret |= d->irq(th->thdev[i]);
835 	}
836 
837 	return ret;
838 }
839 
840 /**
841  * intel_th_alloc() - allocate a new Intel TH device and its subdevices
842  * @dev:	parent device
843  * @devres:	resources indexed by th_mmio_idx
844  * @irq:	irq number
845  */
846 struct intel_th *
847 intel_th_alloc(struct device *dev, const struct intel_th_drvdata *drvdata,
848 	       struct resource *devres, unsigned int ndevres)
849 {
850 	int err, r, nr_mmios = 0;
851 	struct intel_th *th;
852 
853 	th = kzalloc(sizeof(*th), GFP_KERNEL);
854 	if (!th)
855 		return ERR_PTR(-ENOMEM);
856 
857 	th->id = ida_simple_get(&intel_th_ida, 0, 0, GFP_KERNEL);
858 	if (th->id < 0) {
859 		err = th->id;
860 		goto err_alloc;
861 	}
862 
863 	th->major = __register_chrdev(0, 0, TH_POSSIBLE_OUTPUTS,
864 				      "intel_th/output", &intel_th_output_fops);
865 	if (th->major < 0) {
866 		err = th->major;
867 		goto err_ida;
868 	}
869 	th->irq = -1;
870 	th->dev = dev;
871 	th->drvdata = drvdata;
872 
873 	for (r = 0; r < ndevres; r++)
874 		switch (devres[r].flags & IORESOURCE_TYPE_BITS) {
875 		case IORESOURCE_MEM:
876 			th->resource[nr_mmios++] = devres[r];
877 			break;
878 		case IORESOURCE_IRQ:
879 			err = devm_request_irq(dev, devres[r].start,
880 					       intel_th_irq, IRQF_SHARED,
881 					       dev_name(dev), th);
882 			if (err)
883 				goto err_chrdev;
884 
885 			if (th->irq == -1)
886 				th->irq = devres[r].start;
887 			th->num_irqs++;
888 			break;
889 		default:
890 			dev_warn(dev, "Unknown resource type %lx\n",
891 				 devres[r].flags);
892 			break;
893 		}
894 
895 	th->num_resources = nr_mmios;
896 
897 	dev_set_drvdata(dev, th);
898 
899 	pm_runtime_no_callbacks(dev);
900 	pm_runtime_put(dev);
901 	pm_runtime_allow(dev);
902 
903 	err = intel_th_populate(th);
904 	if (err) {
905 		/* free the subdevices and undo everything */
906 		intel_th_free(th);
907 		return ERR_PTR(err);
908 	}
909 
910 	return th;
911 
912 err_chrdev:
913 	__unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
914 			    "intel_th/output");
915 
916 err_ida:
917 	ida_simple_remove(&intel_th_ida, th->id);
918 
919 err_alloc:
920 	kfree(th);
921 
922 	return ERR_PTR(err);
923 }
924 EXPORT_SYMBOL_GPL(intel_th_alloc);
925 
926 void intel_th_free(struct intel_th *th)
927 {
928 	int i;
929 
930 	intel_th_request_hub_module_flush(th);
931 
932 	intel_th_device_remove(th->hub);
933 	for (i = 0; i < th->num_thdevs; i++) {
934 		if (th->thdev[i] != th->hub)
935 			intel_th_device_remove(th->thdev[i]);
936 		th->thdev[i] = NULL;
937 	}
938 
939 	th->num_thdevs = 0;
940 
941 	for (i = 0; i < th->num_irqs; i++)
942 		devm_free_irq(th->dev, th->irq + i, th);
943 
944 	pm_runtime_get_sync(th->dev);
945 	pm_runtime_forbid(th->dev);
946 
947 	__unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
948 			    "intel_th/output");
949 
950 	ida_simple_remove(&intel_th_ida, th->id);
951 
952 	kfree(th);
953 }
954 EXPORT_SYMBOL_GPL(intel_th_free);
955 
956 /**
957  * intel_th_trace_enable() - enable tracing for an output device
958  * @thdev:	output device that requests tracing be enabled
959  */
960 int intel_th_trace_enable(struct intel_th_device *thdev)
961 {
962 	struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
963 	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
964 
965 	if (WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH))
966 		return -EINVAL;
967 
968 	if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
969 		return -EINVAL;
970 
971 	pm_runtime_get_sync(&thdev->dev);
972 	hubdrv->enable(hub, &thdev->output);
973 
974 	return 0;
975 }
976 EXPORT_SYMBOL_GPL(intel_th_trace_enable);
977 
978 /**
979  * intel_th_trace_switch() - execute a switch sequence
980  * @thdev:	output device that requests tracing switch
981  */
982 int intel_th_trace_switch(struct intel_th_device *thdev)
983 {
984 	struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
985 	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
986 
987 	if (WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH))
988 		return -EINVAL;
989 
990 	if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
991 		return -EINVAL;
992 
993 	hubdrv->trig_switch(hub, &thdev->output);
994 
995 	return 0;
996 }
997 EXPORT_SYMBOL_GPL(intel_th_trace_switch);
998 
999 /**
1000  * intel_th_trace_disable() - disable tracing for an output device
1001  * @thdev:	output device that requests tracing be disabled
1002  */
1003 int intel_th_trace_disable(struct intel_th_device *thdev)
1004 {
1005 	struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
1006 	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
1007 
1008 	WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH);
1009 	if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
1010 		return -EINVAL;
1011 
1012 	hubdrv->disable(hub, &thdev->output);
1013 	pm_runtime_put(&thdev->dev);
1014 
1015 	return 0;
1016 }
1017 EXPORT_SYMBOL_GPL(intel_th_trace_disable);
1018 
1019 int intel_th_set_output(struct intel_th_device *thdev,
1020 			unsigned int master)
1021 {
1022 	struct intel_th_device *hub = to_intel_th_hub(thdev);
1023 	struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
1024 	int ret;
1025 
1026 	/* In host mode, this is up to the external debugger, do nothing. */
1027 	if (hub->host_mode)
1028 		return 0;
1029 
1030 	/*
1031 	 * hub is instantiated together with the source device that
1032 	 * calls here, so guaranteed to be present.
1033 	 */
1034 	hubdrv = to_intel_th_driver(hub->dev.driver);
1035 	if (!hubdrv || !try_module_get(hubdrv->driver.owner))
1036 		return -EINVAL;
1037 
1038 	if (!hubdrv->set_output) {
1039 		ret = -ENOTSUPP;
1040 		goto out;
1041 	}
1042 
1043 	ret = hubdrv->set_output(hub, master);
1044 
1045 out:
1046 	module_put(hubdrv->driver.owner);
1047 	return ret;
1048 }
1049 EXPORT_SYMBOL_GPL(intel_th_set_output);
1050 
1051 static int __init intel_th_init(void)
1052 {
1053 	intel_th_debug_init();
1054 
1055 	return bus_register(&intel_th_bus);
1056 }
1057 subsys_initcall(intel_th_init);
1058 
1059 static void __exit intel_th_exit(void)
1060 {
1061 	intel_th_debug_done();
1062 
1063 	bus_unregister(&intel_th_bus);
1064 }
1065 module_exit(intel_th_exit);
1066 
1067 MODULE_LICENSE("GPL v2");
1068 MODULE_DESCRIPTION("Intel(R) Trace Hub controller driver");
1069 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
1070