xref: /openbmc/linux/drivers/bus/fsl-mc/dprc-driver.c (revision 910499e1)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Freescale data path resource container (DPRC) driver
4  *
5  * Copyright (C) 2014-2016 Freescale Semiconductor, Inc.
6  * Copyright 2019-2020 NXP
7  * Author: German Rivera <German.Rivera@freescale.com>
8  *
9  */
10 
11 #include <linux/module.h>
12 #include <linux/slab.h>
13 #include <linux/interrupt.h>
14 #include <linux/msi.h>
15 #include <linux/fsl/mc.h>
16 
17 #include "fsl-mc-private.h"
18 
19 #define FSL_MC_DPRC_DRIVER_NAME    "fsl_mc_dprc"
20 
21 struct fsl_mc_child_objs {
22 	int child_count;
23 	struct fsl_mc_obj_desc *child_array;
24 };
25 
26 static bool fsl_mc_device_match(struct fsl_mc_device *mc_dev,
27 				struct fsl_mc_obj_desc *obj_desc)
28 {
29 	return mc_dev->obj_desc.id == obj_desc->id &&
30 	       strcmp(mc_dev->obj_desc.type, obj_desc->type) == 0;
31 }
32 
33 static bool fsl_mc_obj_desc_is_allocatable(struct fsl_mc_obj_desc *obj)
34 {
35 	if (strcmp(obj->type, "dpmcp") == 0 ||
36 	    strcmp(obj->type, "dpcon") == 0 ||
37 	    strcmp(obj->type, "dpbp") == 0)
38 		return true;
39 	else
40 		return false;
41 }
42 
43 static int __fsl_mc_device_remove_if_not_in_mc(struct device *dev, void *data)
44 {
45 	int i;
46 	struct fsl_mc_child_objs *objs;
47 	struct fsl_mc_device *mc_dev;
48 
49 	mc_dev = to_fsl_mc_device(dev);
50 	objs = data;
51 
52 	for (i = 0; i < objs->child_count; i++) {
53 		struct fsl_mc_obj_desc *obj_desc = &objs->child_array[i];
54 
55 		if (strlen(obj_desc->type) != 0 &&
56 		    fsl_mc_device_match(mc_dev, obj_desc))
57 			break;
58 	}
59 
60 	if (i == objs->child_count)
61 		fsl_mc_device_remove(mc_dev);
62 
63 	return 0;
64 }
65 
66 static int __fsl_mc_device_remove(struct device *dev, void *data)
67 {
68 	fsl_mc_device_remove(to_fsl_mc_device(dev));
69 	return 0;
70 }
71 
72 /**
73  * dprc_remove_devices - Removes devices for objects removed from a DPRC
74  *
75  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
76  * @obj_desc_array: array of object descriptors for child objects currently
77  * present in the DPRC in the MC.
78  * @num_child_objects_in_mc: number of entries in obj_desc_array
79  *
80  * Synchronizes the state of the Linux bus driver with the actual state of
81  * the MC by removing devices that represent MC objects that have
82  * been dynamically removed in the physical DPRC.
83  */
84 void dprc_remove_devices(struct fsl_mc_device *mc_bus_dev,
85 			 struct fsl_mc_obj_desc *obj_desc_array,
86 			 int num_child_objects_in_mc)
87 {
88 	if (num_child_objects_in_mc != 0) {
89 		/*
90 		 * Remove child objects that are in the DPRC in Linux,
91 		 * but not in the MC:
92 		 */
93 		struct fsl_mc_child_objs objs;
94 
95 		objs.child_count = num_child_objects_in_mc;
96 		objs.child_array = obj_desc_array;
97 		device_for_each_child(&mc_bus_dev->dev, &objs,
98 				      __fsl_mc_device_remove_if_not_in_mc);
99 	} else {
100 		/*
101 		 * There are no child objects for this DPRC in the MC.
102 		 * So, remove all the child devices from Linux:
103 		 */
104 		device_for_each_child(&mc_bus_dev->dev, NULL,
105 				      __fsl_mc_device_remove);
106 	}
107 }
108 EXPORT_SYMBOL_GPL(dprc_remove_devices);
109 
110 static int __fsl_mc_device_match(struct device *dev, void *data)
111 {
112 	struct fsl_mc_obj_desc *obj_desc = data;
113 	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
114 
115 	return fsl_mc_device_match(mc_dev, obj_desc);
116 }
117 
118 struct fsl_mc_device *fsl_mc_device_lookup(struct fsl_mc_obj_desc *obj_desc,
119 					   struct fsl_mc_device *mc_bus_dev)
120 {
121 	struct device *dev;
122 
123 	dev = device_find_child(&mc_bus_dev->dev, obj_desc,
124 				__fsl_mc_device_match);
125 
126 	return dev ? to_fsl_mc_device(dev) : NULL;
127 }
128 
129 /**
130  * check_plugged_state_change - Check change in an MC object's plugged state
131  *
132  * @mc_dev: pointer to the fsl-mc device for a given MC object
133  * @obj_desc: pointer to the MC object's descriptor in the MC
134  *
135  * If the plugged state has changed from unplugged to plugged, the fsl-mc
136  * device is bound to the corresponding device driver.
137  * If the plugged state has changed from plugged to unplugged, the fsl-mc
138  * device is unbound from the corresponding device driver.
139  */
140 static void check_plugged_state_change(struct fsl_mc_device *mc_dev,
141 				       struct fsl_mc_obj_desc *obj_desc)
142 {
143 	int error;
144 	u32 plugged_flag_at_mc =
145 			obj_desc->state & FSL_MC_OBJ_STATE_PLUGGED;
146 
147 	if (plugged_flag_at_mc !=
148 	    (mc_dev->obj_desc.state & FSL_MC_OBJ_STATE_PLUGGED)) {
149 		if (plugged_flag_at_mc) {
150 			mc_dev->obj_desc.state |= FSL_MC_OBJ_STATE_PLUGGED;
151 			error = device_attach(&mc_dev->dev);
152 			if (error < 0) {
153 				dev_err(&mc_dev->dev,
154 					"device_attach() failed: %d\n",
155 					error);
156 			}
157 		} else {
158 			mc_dev->obj_desc.state &= ~FSL_MC_OBJ_STATE_PLUGGED;
159 			device_release_driver(&mc_dev->dev);
160 		}
161 	}
162 }
163 
164 static void fsl_mc_obj_device_add(struct fsl_mc_device *mc_bus_dev,
165 				  struct fsl_mc_obj_desc *obj_desc)
166 {
167 	int error;
168 	struct fsl_mc_device *child_dev;
169 
170 	/*
171 	 * Check if device is already known to Linux:
172 	 */
173 	child_dev = fsl_mc_device_lookup(obj_desc, mc_bus_dev);
174 	if (child_dev) {
175 		check_plugged_state_change(child_dev, obj_desc);
176 		put_device(&child_dev->dev);
177 	} else {
178 		error = fsl_mc_device_add(obj_desc, NULL, &mc_bus_dev->dev,
179 					  &child_dev);
180 		if (error < 0)
181 			return;
182 	}
183 }
184 
185 /**
186  * dprc_add_new_devices - Adds devices to the logical bus for a DPRC
187  *
188  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
189  * @obj_desc_array: array of device descriptors for child devices currently
190  * present in the physical DPRC.
191  * @num_child_objects_in_mc: number of entries in obj_desc_array
192  *
193  * Synchronizes the state of the Linux bus driver with the actual
194  * state of the MC by adding objects that have been newly discovered
195  * in the physical DPRC.
196  */
197 static void dprc_add_new_devices(struct fsl_mc_device *mc_bus_dev,
198 				 struct fsl_mc_obj_desc *obj_desc_array,
199 				 int num_child_objects_in_mc)
200 {
201 	int i;
202 
203 	/* probe the allocable objects first */
204 	for (i = 0; i < num_child_objects_in_mc; i++) {
205 		struct fsl_mc_obj_desc *obj_desc = &obj_desc_array[i];
206 
207 		if (strlen(obj_desc->type) > 0 &&
208 		    fsl_mc_obj_desc_is_allocatable(obj_desc))
209 			fsl_mc_obj_device_add(mc_bus_dev, obj_desc);
210 	}
211 
212 	for (i = 0; i < num_child_objects_in_mc; i++) {
213 		struct fsl_mc_obj_desc *obj_desc = &obj_desc_array[i];
214 
215 		if (strlen(obj_desc->type) > 0 &&
216 		    !fsl_mc_obj_desc_is_allocatable(obj_desc))
217 			fsl_mc_obj_device_add(mc_bus_dev, obj_desc);
218 	}
219 }
220 
221 /**
222  * dprc_scan_objects - Discover objects in a DPRC
223  *
224  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
225  * @alloc_interrupts: if true the function allocates the interrupt pool,
226  * otherwise the interrupt allocation is delayed
227  *
228  * Detects objects added and removed from a DPRC and synchronizes the
229  * state of the Linux bus driver, MC by adding and removing
230  * devices accordingly.
231  * Two types of devices can be found in a DPRC: allocatable objects (e.g.,
232  * dpbp, dpmcp) and non-allocatable devices (e.g., dprc, dpni).
233  * All allocatable devices needed to be probed before all non-allocatable
234  * devices, to ensure that device drivers for non-allocatable
235  * devices can allocate any type of allocatable devices.
236  * That is, we need to ensure that the corresponding resource pools are
237  * populated before they can get allocation requests from probe callbacks
238  * of the device drivers for the non-allocatable devices.
239  */
240 int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
241 		      bool alloc_interrupts)
242 {
243 	int num_child_objects;
244 	int dprc_get_obj_failures;
245 	int error;
246 	unsigned int irq_count = mc_bus_dev->obj_desc.irq_count;
247 	struct fsl_mc_obj_desc *child_obj_desc_array = NULL;
248 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
249 
250 	error = dprc_get_obj_count(mc_bus_dev->mc_io,
251 				   0,
252 				   mc_bus_dev->mc_handle,
253 				   &num_child_objects);
254 	if (error < 0) {
255 		dev_err(&mc_bus_dev->dev, "dprc_get_obj_count() failed: %d\n",
256 			error);
257 		return error;
258 	}
259 
260 	if (num_child_objects != 0) {
261 		int i;
262 
263 		child_obj_desc_array =
264 		    devm_kmalloc_array(&mc_bus_dev->dev, num_child_objects,
265 				       sizeof(*child_obj_desc_array),
266 				       GFP_KERNEL);
267 		if (!child_obj_desc_array)
268 			return -ENOMEM;
269 
270 		/*
271 		 * Discover objects currently present in the physical DPRC:
272 		 */
273 		dprc_get_obj_failures = 0;
274 		for (i = 0; i < num_child_objects; i++) {
275 			struct fsl_mc_obj_desc *obj_desc =
276 			    &child_obj_desc_array[i];
277 
278 			error = dprc_get_obj(mc_bus_dev->mc_io,
279 					     0,
280 					     mc_bus_dev->mc_handle,
281 					     i, obj_desc);
282 			if (error < 0) {
283 				dev_err(&mc_bus_dev->dev,
284 					"dprc_get_obj(i=%d) failed: %d\n",
285 					i, error);
286 				/*
287 				 * Mark the obj entry as "invalid", by using the
288 				 * empty string as obj type:
289 				 */
290 				obj_desc->type[0] = '\0';
291 				obj_desc->id = error;
292 				dprc_get_obj_failures++;
293 				continue;
294 			}
295 
296 			/*
297 			 * add a quirk for all versions of dpsec < 4.0...none
298 			 * are coherent regardless of what the MC reports.
299 			 */
300 			if ((strcmp(obj_desc->type, "dpseci") == 0) &&
301 			    (obj_desc->ver_major < 4))
302 				obj_desc->flags |=
303 					FSL_MC_OBJ_FLAG_NO_MEM_SHAREABILITY;
304 
305 			irq_count += obj_desc->irq_count;
306 			dev_dbg(&mc_bus_dev->dev,
307 				"Discovered object: type %s, id %d\n",
308 				obj_desc->type, obj_desc->id);
309 		}
310 
311 		if (dprc_get_obj_failures != 0) {
312 			dev_err(&mc_bus_dev->dev,
313 				"%d out of %d devices could not be retrieved\n",
314 				dprc_get_obj_failures, num_child_objects);
315 		}
316 	}
317 
318 	/*
319 	 * Allocate IRQ's before binding the scanned devices with their
320 	 * respective drivers.
321 	 */
322 	if (dev_get_msi_domain(&mc_bus_dev->dev)) {
323 		if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
324 			dev_warn(&mc_bus_dev->dev,
325 				 "IRQs needed (%u) exceed IRQs preallocated (%u)\n",
326 				 irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
327 		}
328 
329 		if (alloc_interrupts && !mc_bus->irq_resources) {
330 			error = fsl_mc_populate_irq_pool(mc_bus_dev,
331 					 FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
332 			if (error < 0)
333 				return error;
334 		}
335 	}
336 
337 	dprc_remove_devices(mc_bus_dev, child_obj_desc_array,
338 			    num_child_objects);
339 
340 	dprc_add_new_devices(mc_bus_dev, child_obj_desc_array,
341 			     num_child_objects);
342 
343 	if (child_obj_desc_array)
344 		devm_kfree(&mc_bus_dev->dev, child_obj_desc_array);
345 
346 	return 0;
347 }
348 
349 /**
350  * dprc_scan_container - Scans a physical DPRC and synchronizes Linux bus state
351  *
352  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
353  *
354  * Scans the physical DPRC and synchronizes the state of the Linux
355  * bus driver with the actual state of the MC by adding and removing
356  * devices as appropriate.
357  */
358 int dprc_scan_container(struct fsl_mc_device *mc_bus_dev,
359 			bool alloc_interrupts)
360 {
361 	int error = 0;
362 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
363 
364 	fsl_mc_init_all_resource_pools(mc_bus_dev);
365 
366 	/*
367 	 * Discover objects in the DPRC:
368 	 */
369 	mutex_lock(&mc_bus->scan_mutex);
370 	error = dprc_scan_objects(mc_bus_dev, alloc_interrupts);
371 	mutex_unlock(&mc_bus->scan_mutex);
372 
373 	return error;
374 }
375 EXPORT_SYMBOL_GPL(dprc_scan_container);
376 /**
377  * dprc_irq0_handler - Regular ISR for DPRC interrupt 0
378  *
379  * @irq: IRQ number of the interrupt being handled
380  * @arg: Pointer to device structure
381  */
382 static irqreturn_t dprc_irq0_handler(int irq_num, void *arg)
383 {
384 	return IRQ_WAKE_THREAD;
385 }
386 
387 /**
388  * dprc_irq0_handler_thread - Handler thread function for DPRC interrupt 0
389  *
390  * @irq: IRQ number of the interrupt being handled
391  * @arg: Pointer to device structure
392  */
393 static irqreturn_t dprc_irq0_handler_thread(int irq_num, void *arg)
394 {
395 	int error;
396 	u32 status;
397 	struct device *dev = arg;
398 	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
399 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
400 	struct fsl_mc_io *mc_io = mc_dev->mc_io;
401 	struct msi_desc *msi_desc = mc_dev->irqs[0]->msi_desc;
402 
403 	dev_dbg(dev, "DPRC IRQ %d triggered on CPU %u\n",
404 		irq_num, smp_processor_id());
405 
406 	if (!(mc_dev->flags & FSL_MC_IS_DPRC))
407 		return IRQ_HANDLED;
408 
409 	mutex_lock(&mc_bus->scan_mutex);
410 	if (!msi_desc || msi_desc->irq != (u32)irq_num)
411 		goto out;
412 
413 	status = 0;
414 	error = dprc_get_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
415 				    &status);
416 	if (error < 0) {
417 		dev_err(dev,
418 			"dprc_get_irq_status() failed: %d\n", error);
419 		goto out;
420 	}
421 
422 	error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
423 				      status);
424 	if (error < 0) {
425 		dev_err(dev,
426 			"dprc_clear_irq_status() failed: %d\n", error);
427 		goto out;
428 	}
429 
430 	if (status & (DPRC_IRQ_EVENT_OBJ_ADDED |
431 		      DPRC_IRQ_EVENT_OBJ_REMOVED |
432 		      DPRC_IRQ_EVENT_CONTAINER_DESTROYED |
433 		      DPRC_IRQ_EVENT_OBJ_DESTROYED |
434 		      DPRC_IRQ_EVENT_OBJ_CREATED)) {
435 
436 		error = dprc_scan_objects(mc_dev, true);
437 		if (error < 0) {
438 			/*
439 			 * If the error is -ENXIO, we ignore it, as it indicates
440 			 * that the object scan was aborted, as we detected that
441 			 * an object was removed from the DPRC in the MC, while
442 			 * we were scanning the DPRC.
443 			 */
444 			if (error != -ENXIO) {
445 				dev_err(dev, "dprc_scan_objects() failed: %d\n",
446 					error);
447 			}
448 
449 			goto out;
450 		}
451 	}
452 
453 out:
454 	mutex_unlock(&mc_bus->scan_mutex);
455 	return IRQ_HANDLED;
456 }
457 
458 /*
459  * Disable and clear interrupt for a given DPRC object
460  */
461 int disable_dprc_irq(struct fsl_mc_device *mc_dev)
462 {
463 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
464 	int error;
465 	struct fsl_mc_io *mc_io = mc_dev->mc_io;
466 
467 	/*
468 	 * Disable generation of interrupt, while we configure it:
469 	 */
470 	error = dprc_set_irq_enable(mc_io, 0, mc_dev->mc_handle, 0, 0);
471 	if (error < 0) {
472 		dev_err(&mc_dev->dev,
473 			"Disabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
474 			error);
475 		return error;
476 	}
477 
478 	/*
479 	 * Disable all interrupt causes for the interrupt:
480 	 */
481 	error = dprc_set_irq_mask(mc_io, 0, mc_dev->mc_handle, 0, 0x0);
482 	if (error < 0) {
483 		dev_err(&mc_dev->dev,
484 			"Disabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
485 			error);
486 		return error;
487 	}
488 
489 	/*
490 	 * Clear any leftover interrupts:
491 	 */
492 	error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0, ~0x0U);
493 	if (error < 0) {
494 		dev_err(&mc_dev->dev,
495 			"Disabling DPRC IRQ failed: dprc_clear_irq_status() failed: %d\n",
496 			error);
497 		return error;
498 	}
499 
500 	mc_bus->irq_enabled = 0;
501 
502 	return 0;
503 }
504 
505 int get_dprc_irq_state(struct fsl_mc_device *mc_dev)
506 {
507 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
508 
509 	return mc_bus->irq_enabled;
510 }
511 
512 static int register_dprc_irq_handler(struct fsl_mc_device *mc_dev)
513 {
514 	int error;
515 	struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
516 
517 	/*
518 	 * NOTE: devm_request_threaded_irq() invokes the device-specific
519 	 * function that programs the MSI physically in the device
520 	 */
521 	error = devm_request_threaded_irq(&mc_dev->dev,
522 					  irq->msi_desc->irq,
523 					  dprc_irq0_handler,
524 					  dprc_irq0_handler_thread,
525 					  IRQF_NO_SUSPEND | IRQF_ONESHOT,
526 					  dev_name(&mc_dev->dev),
527 					  &mc_dev->dev);
528 	if (error < 0) {
529 		dev_err(&mc_dev->dev,
530 			"devm_request_threaded_irq() failed: %d\n",
531 			error);
532 		return error;
533 	}
534 
535 	return 0;
536 }
537 
538 int enable_dprc_irq(struct fsl_mc_device *mc_dev)
539 {
540 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
541 	int error;
542 
543 	/*
544 	 * Enable all interrupt causes for the interrupt:
545 	 */
546 	error = dprc_set_irq_mask(mc_dev->mc_io, 0, mc_dev->mc_handle, 0,
547 				  ~0x0u);
548 	if (error < 0) {
549 		dev_err(&mc_dev->dev,
550 			"Enabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
551 			error);
552 
553 		return error;
554 	}
555 
556 	/*
557 	 * Enable generation of the interrupt:
558 	 */
559 	error = dprc_set_irq_enable(mc_dev->mc_io, 0, mc_dev->mc_handle, 0, 1);
560 	if (error < 0) {
561 		dev_err(&mc_dev->dev,
562 			"Enabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
563 			error);
564 
565 		return error;
566 	}
567 
568 	mc_bus->irq_enabled = 1;
569 
570 	return 0;
571 }
572 
573 /*
574  * Setup interrupt for a given DPRC device
575  */
576 static int dprc_setup_irq(struct fsl_mc_device *mc_dev)
577 {
578 	int error;
579 
580 	error = fsl_mc_allocate_irqs(mc_dev);
581 	if (error < 0)
582 		return error;
583 
584 	error = disable_dprc_irq(mc_dev);
585 	if (error < 0)
586 		goto error_free_irqs;
587 
588 	error = register_dprc_irq_handler(mc_dev);
589 	if (error < 0)
590 		goto error_free_irqs;
591 
592 	error = enable_dprc_irq(mc_dev);
593 	if (error < 0)
594 		goto error_free_irqs;
595 
596 	return 0;
597 
598 error_free_irqs:
599 	fsl_mc_free_irqs(mc_dev);
600 	return error;
601 }
602 
603 /**
604  * dprc_setup - opens and creates a mc_io for DPRC
605  *
606  * @mc_dev: Pointer to fsl-mc device representing a DPRC
607  *
608  * It opens the physical DPRC in the MC.
609  * It configures the DPRC portal used to communicate with MC
610  */
611 
612 int dprc_setup(struct fsl_mc_device *mc_dev)
613 {
614 	struct device *parent_dev = mc_dev->dev.parent;
615 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
616 	struct irq_domain *mc_msi_domain;
617 	bool mc_io_created = false;
618 	bool msi_domain_set = false;
619 	bool uapi_created = false;
620 	u16 major_ver, minor_ver;
621 	size_t region_size;
622 	int error;
623 
624 	if (!is_fsl_mc_bus_dprc(mc_dev))
625 		return -EINVAL;
626 
627 	if (dev_get_msi_domain(&mc_dev->dev))
628 		return -EINVAL;
629 
630 	if (!mc_dev->mc_io) {
631 		/*
632 		 * This is a child DPRC:
633 		 */
634 		if (!dev_is_fsl_mc(parent_dev))
635 			return -EINVAL;
636 
637 		if (mc_dev->obj_desc.region_count == 0)
638 			return -EINVAL;
639 
640 		region_size = resource_size(mc_dev->regions);
641 
642 		error = fsl_create_mc_io(&mc_dev->dev,
643 					 mc_dev->regions[0].start,
644 					 region_size,
645 					 NULL,
646 					 FSL_MC_IO_ATOMIC_CONTEXT_PORTAL,
647 					 &mc_dev->mc_io);
648 		if (error < 0)
649 			return error;
650 
651 		mc_io_created = true;
652 	} else {
653 		error = fsl_mc_uapi_create_device_file(mc_bus);
654 		if (error < 0)
655 			return -EPROBE_DEFER;
656 		uapi_created = true;
657 	}
658 
659 	mc_msi_domain = fsl_mc_find_msi_domain(&mc_dev->dev);
660 	if (!mc_msi_domain) {
661 		dev_warn(&mc_dev->dev,
662 			 "WARNING: MC bus without interrupt support\n");
663 	} else {
664 		dev_set_msi_domain(&mc_dev->dev, mc_msi_domain);
665 		msi_domain_set = true;
666 	}
667 
668 	error = dprc_open(mc_dev->mc_io, 0, mc_dev->obj_desc.id,
669 			  &mc_dev->mc_handle);
670 	if (error < 0) {
671 		dev_err(&mc_dev->dev, "dprc_open() failed: %d\n", error);
672 		goto error_cleanup_msi_domain;
673 	}
674 
675 	error = dprc_get_attributes(mc_dev->mc_io, 0, mc_dev->mc_handle,
676 				    &mc_bus->dprc_attr);
677 	if (error < 0) {
678 		dev_err(&mc_dev->dev, "dprc_get_attributes() failed: %d\n",
679 			error);
680 		goto error_cleanup_open;
681 	}
682 
683 	error = dprc_get_api_version(mc_dev->mc_io, 0,
684 				     &major_ver,
685 				     &minor_ver);
686 	if (error < 0) {
687 		dev_err(&mc_dev->dev, "dprc_get_api_version() failed: %d\n",
688 			error);
689 		goto error_cleanup_open;
690 	}
691 
692 	if (major_ver < DPRC_MIN_VER_MAJOR) {
693 		dev_err(&mc_dev->dev,
694 			"ERROR: DPRC version %d.%d not supported\n",
695 			major_ver, minor_ver);
696 		error = -ENOTSUPP;
697 		goto error_cleanup_open;
698 	}
699 
700 	return 0;
701 
702 error_cleanup_open:
703 	(void)dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
704 
705 error_cleanup_msi_domain:
706 	if (msi_domain_set)
707 		dev_set_msi_domain(&mc_dev->dev, NULL);
708 
709 	if (mc_io_created) {
710 		fsl_destroy_mc_io(mc_dev->mc_io);
711 		mc_dev->mc_io = NULL;
712 	}
713 
714 	if (uapi_created)
715 		fsl_mc_uapi_remove_device_file(mc_bus);
716 
717 	return error;
718 }
719 EXPORT_SYMBOL_GPL(dprc_setup);
720 
721 /**
722  * dprc_probe - callback invoked when a DPRC is being bound to this driver
723  *
724  * @mc_dev: Pointer to fsl-mc device representing a DPRC
725  *
726  * It opens the physical DPRC in the MC.
727  * It scans the DPRC to discover the MC objects contained in it.
728  * It creates the interrupt pool for the MC bus associated with the DPRC.
729  * It configures the interrupts for the DPRC device itself.
730  */
731 static int dprc_probe(struct fsl_mc_device *mc_dev)
732 {
733 	int error;
734 
735 	error = dprc_setup(mc_dev);
736 	if (error < 0)
737 		return error;
738 
739 	/*
740 	 * Discover MC objects in DPRC object:
741 	 */
742 	error = dprc_scan_container(mc_dev, true);
743 	if (error < 0)
744 		goto dprc_cleanup;
745 
746 	/*
747 	 * Configure interrupt for the DPRC object associated with this MC bus:
748 	 */
749 	error = dprc_setup_irq(mc_dev);
750 	if (error < 0)
751 		goto scan_cleanup;
752 
753 	dev_info(&mc_dev->dev, "DPRC device bound to driver");
754 	return 0;
755 
756 scan_cleanup:
757 	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
758 dprc_cleanup:
759 	dprc_cleanup(mc_dev);
760 	return error;
761 }
762 
763 /*
764  * Tear down interrupt for a given DPRC object
765  */
766 static void dprc_teardown_irq(struct fsl_mc_device *mc_dev)
767 {
768 	struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
769 
770 	(void)disable_dprc_irq(mc_dev);
771 
772 	devm_free_irq(&mc_dev->dev, irq->msi_desc->irq, &mc_dev->dev);
773 
774 	fsl_mc_free_irqs(mc_dev);
775 }
776 
777 /**
778  * dprc_cleanup - function that cleanups a DPRC
779  *
780  * @mc_dev: Pointer to fsl-mc device representing the DPRC
781  *
782  * It closes the DPRC device in the MC.
783  * It destroys the interrupt pool associated with this MC bus.
784  */
785 
786 int dprc_cleanup(struct fsl_mc_device *mc_dev)
787 {
788 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
789 	int error;
790 
791 	/* this function should be called only for DPRCs, it
792 	 * is an error to call it for regular objects
793 	 */
794 	if (!is_fsl_mc_bus_dprc(mc_dev))
795 		return -EINVAL;
796 
797 	if (dev_get_msi_domain(&mc_dev->dev)) {
798 		fsl_mc_cleanup_irq_pool(mc_dev);
799 		dev_set_msi_domain(&mc_dev->dev, NULL);
800 	}
801 
802 	fsl_mc_cleanup_all_resource_pools(mc_dev);
803 
804 	/* if this step fails we cannot go further with cleanup as there is no way of
805 	 * communicating with the firmware
806 	 */
807 	if (!mc_dev->mc_io) {
808 		dev_err(&mc_dev->dev, "mc_io is NULL, tear down cannot be performed in firmware\n");
809 		return -EINVAL;
810 	}
811 
812 	error = dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
813 	if (error < 0)
814 		dev_err(&mc_dev->dev, "dprc_close() failed: %d\n", error);
815 
816 	if (!fsl_mc_is_root_dprc(&mc_dev->dev)) {
817 		fsl_destroy_mc_io(mc_dev->mc_io);
818 		mc_dev->mc_io = NULL;
819 	} else {
820 		fsl_mc_uapi_remove_device_file(mc_bus);
821 	}
822 
823 	return 0;
824 }
825 EXPORT_SYMBOL_GPL(dprc_cleanup);
826 
827 /**
828  * dprc_remove - callback invoked when a DPRC is being unbound from this driver
829  *
830  * @mc_dev: Pointer to fsl-mc device representing the DPRC
831  *
832  * It removes the DPRC's child objects from Linux (not from the MC) and
833  * closes the DPRC device in the MC.
834  * It tears down the interrupts that were configured for the DPRC device.
835  * It destroys the interrupt pool associated with this MC bus.
836  */
837 static int dprc_remove(struct fsl_mc_device *mc_dev)
838 {
839 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
840 
841 	if (!is_fsl_mc_bus_dprc(mc_dev))
842 		return -EINVAL;
843 
844 	if (!mc_bus->irq_resources)
845 		return -EINVAL;
846 
847 	if (dev_get_msi_domain(&mc_dev->dev))
848 		dprc_teardown_irq(mc_dev);
849 
850 	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
851 
852 	dprc_cleanup(mc_dev);
853 
854 	dev_info(&mc_dev->dev, "DPRC device unbound from driver");
855 	return 0;
856 }
857 
858 static const struct fsl_mc_device_id match_id_table[] = {
859 	{
860 	 .vendor = FSL_MC_VENDOR_FREESCALE,
861 	 .obj_type = "dprc"},
862 	{.vendor = 0x0},
863 };
864 
865 static struct fsl_mc_driver dprc_driver = {
866 	.driver = {
867 		   .name = FSL_MC_DPRC_DRIVER_NAME,
868 		   .owner = THIS_MODULE,
869 		   .pm = NULL,
870 		   },
871 	.match_id_table = match_id_table,
872 	.probe = dprc_probe,
873 	.remove = dprc_remove,
874 };
875 
876 int __init dprc_driver_init(void)
877 {
878 	return fsl_mc_driver_register(&dprc_driver);
879 }
880 
881 void dprc_driver_exit(void)
882 {
883 	fsl_mc_driver_unregister(&dprc_driver);
884 }
885