xref: /linux/drivers/bus/fsl-mc/dprc-driver.c (revision 44f57d78)
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  * Author: German Rivera <German.Rivera@freescale.com>
7  *
8  */
9 
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 #include <linux/interrupt.h>
13 #include <linux/msi.h>
14 #include <linux/fsl/mc.h>
15 
16 #include "fsl-mc-private.h"
17 
18 #define FSL_MC_DPRC_DRIVER_NAME    "fsl_mc_dprc"
19 
20 struct fsl_mc_child_objs {
21 	int child_count;
22 	struct fsl_mc_obj_desc *child_array;
23 };
24 
25 static bool fsl_mc_device_match(struct fsl_mc_device *mc_dev,
26 				struct fsl_mc_obj_desc *obj_desc)
27 {
28 	return mc_dev->obj_desc.id == obj_desc->id &&
29 	       strcmp(mc_dev->obj_desc.type, obj_desc->type) == 0;
30 
31 }
32 
33 static int __fsl_mc_device_remove_if_not_in_mc(struct device *dev, void *data)
34 {
35 	int i;
36 	struct fsl_mc_child_objs *objs;
37 	struct fsl_mc_device *mc_dev;
38 
39 	mc_dev = to_fsl_mc_device(dev);
40 	objs = data;
41 
42 	for (i = 0; i < objs->child_count; i++) {
43 		struct fsl_mc_obj_desc *obj_desc = &objs->child_array[i];
44 
45 		if (strlen(obj_desc->type) != 0 &&
46 		    fsl_mc_device_match(mc_dev, obj_desc))
47 			break;
48 	}
49 
50 	if (i == objs->child_count)
51 		fsl_mc_device_remove(mc_dev);
52 
53 	return 0;
54 }
55 
56 static int __fsl_mc_device_remove(struct device *dev, void *data)
57 {
58 	fsl_mc_device_remove(to_fsl_mc_device(dev));
59 	return 0;
60 }
61 
62 /**
63  * dprc_remove_devices - Removes devices for objects removed from a DPRC
64  *
65  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
66  * @obj_desc_array: array of object descriptors for child objects currently
67  * present in the DPRC in the MC.
68  * @num_child_objects_in_mc: number of entries in obj_desc_array
69  *
70  * Synchronizes the state of the Linux bus driver with the actual state of
71  * the MC by removing devices that represent MC objects that have
72  * been dynamically removed in the physical DPRC.
73  */
74 static void dprc_remove_devices(struct fsl_mc_device *mc_bus_dev,
75 				struct fsl_mc_obj_desc *obj_desc_array,
76 				int num_child_objects_in_mc)
77 {
78 	if (num_child_objects_in_mc != 0) {
79 		/*
80 		 * Remove child objects that are in the DPRC in Linux,
81 		 * but not in the MC:
82 		 */
83 		struct fsl_mc_child_objs objs;
84 
85 		objs.child_count = num_child_objects_in_mc;
86 		objs.child_array = obj_desc_array;
87 		device_for_each_child(&mc_bus_dev->dev, &objs,
88 				      __fsl_mc_device_remove_if_not_in_mc);
89 	} else {
90 		/*
91 		 * There are no child objects for this DPRC in the MC.
92 		 * So, remove all the child devices from Linux:
93 		 */
94 		device_for_each_child(&mc_bus_dev->dev, NULL,
95 				      __fsl_mc_device_remove);
96 	}
97 }
98 
99 static int __fsl_mc_device_match(struct device *dev, void *data)
100 {
101 	struct fsl_mc_obj_desc *obj_desc = data;
102 	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
103 
104 	return fsl_mc_device_match(mc_dev, obj_desc);
105 }
106 
107 static struct fsl_mc_device *fsl_mc_device_lookup(struct fsl_mc_obj_desc
108 								*obj_desc,
109 						  struct fsl_mc_device
110 								*mc_bus_dev)
111 {
112 	struct device *dev;
113 
114 	dev = device_find_child(&mc_bus_dev->dev, obj_desc,
115 				__fsl_mc_device_match);
116 
117 	return dev ? to_fsl_mc_device(dev) : NULL;
118 }
119 
120 /**
121  * check_plugged_state_change - Check change in an MC object's plugged state
122  *
123  * @mc_dev: pointer to the fsl-mc device for a given MC object
124  * @obj_desc: pointer to the MC object's descriptor in the MC
125  *
126  * If the plugged state has changed from unplugged to plugged, the fsl-mc
127  * device is bound to the corresponding device driver.
128  * If the plugged state has changed from plugged to unplugged, the fsl-mc
129  * device is unbound from the corresponding device driver.
130  */
131 static void check_plugged_state_change(struct fsl_mc_device *mc_dev,
132 				       struct fsl_mc_obj_desc *obj_desc)
133 {
134 	int error;
135 	u32 plugged_flag_at_mc =
136 			obj_desc->state & FSL_MC_OBJ_STATE_PLUGGED;
137 
138 	if (plugged_flag_at_mc !=
139 	    (mc_dev->obj_desc.state & FSL_MC_OBJ_STATE_PLUGGED)) {
140 		if (plugged_flag_at_mc) {
141 			mc_dev->obj_desc.state |= FSL_MC_OBJ_STATE_PLUGGED;
142 			error = device_attach(&mc_dev->dev);
143 			if (error < 0) {
144 				dev_err(&mc_dev->dev,
145 					"device_attach() failed: %d\n",
146 					error);
147 			}
148 		} else {
149 			mc_dev->obj_desc.state &= ~FSL_MC_OBJ_STATE_PLUGGED;
150 			device_release_driver(&mc_dev->dev);
151 		}
152 	}
153 }
154 
155 /**
156  * dprc_add_new_devices - Adds devices to the logical bus for a DPRC
157  *
158  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
159  * @obj_desc_array: array of device descriptors for child devices currently
160  * present in the physical DPRC.
161  * @num_child_objects_in_mc: number of entries in obj_desc_array
162  *
163  * Synchronizes the state of the Linux bus driver with the actual
164  * state of the MC by adding objects that have been newly discovered
165  * in the physical DPRC.
166  */
167 static void dprc_add_new_devices(struct fsl_mc_device *mc_bus_dev,
168 				 struct fsl_mc_obj_desc *obj_desc_array,
169 				 int num_child_objects_in_mc)
170 {
171 	int error;
172 	int i;
173 
174 	for (i = 0; i < num_child_objects_in_mc; i++) {
175 		struct fsl_mc_device *child_dev;
176 		struct fsl_mc_obj_desc *obj_desc = &obj_desc_array[i];
177 
178 		if (strlen(obj_desc->type) == 0)
179 			continue;
180 
181 		/*
182 		 * Check if device is already known to Linux:
183 		 */
184 		child_dev = fsl_mc_device_lookup(obj_desc, mc_bus_dev);
185 		if (child_dev) {
186 			check_plugged_state_change(child_dev, obj_desc);
187 			put_device(&child_dev->dev);
188 			continue;
189 		}
190 
191 		error = fsl_mc_device_add(obj_desc, NULL, &mc_bus_dev->dev,
192 					  &child_dev);
193 		if (error < 0)
194 			continue;
195 	}
196 }
197 
198 /**
199  * dprc_scan_objects - Discover objects in a DPRC
200  *
201  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
202  * @total_irq_count: If argument is provided the function populates the
203  * total number of IRQs created by objects in the DPRC.
204  *
205  * Detects objects added and removed from a DPRC and synchronizes the
206  * state of the Linux bus driver, MC by adding and removing
207  * devices accordingly.
208  * Two types of devices can be found in a DPRC: allocatable objects (e.g.,
209  * dpbp, dpmcp) and non-allocatable devices (e.g., dprc, dpni).
210  * All allocatable devices needed to be probed before all non-allocatable
211  * devices, to ensure that device drivers for non-allocatable
212  * devices can allocate any type of allocatable devices.
213  * That is, we need to ensure that the corresponding resource pools are
214  * populated before they can get allocation requests from probe callbacks
215  * of the device drivers for the non-allocatable devices.
216  */
217 static int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
218 			     unsigned int *total_irq_count)
219 {
220 	int num_child_objects;
221 	int dprc_get_obj_failures;
222 	int error;
223 	unsigned int irq_count = mc_bus_dev->obj_desc.irq_count;
224 	struct fsl_mc_obj_desc *child_obj_desc_array = NULL;
225 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
226 
227 	error = dprc_get_obj_count(mc_bus_dev->mc_io,
228 				   0,
229 				   mc_bus_dev->mc_handle,
230 				   &num_child_objects);
231 	if (error < 0) {
232 		dev_err(&mc_bus_dev->dev, "dprc_get_obj_count() failed: %d\n",
233 			error);
234 		return error;
235 	}
236 
237 	if (num_child_objects != 0) {
238 		int i;
239 
240 		child_obj_desc_array =
241 		    devm_kmalloc_array(&mc_bus_dev->dev, num_child_objects,
242 				       sizeof(*child_obj_desc_array),
243 				       GFP_KERNEL);
244 		if (!child_obj_desc_array)
245 			return -ENOMEM;
246 
247 		/*
248 		 * Discover objects currently present in the physical DPRC:
249 		 */
250 		dprc_get_obj_failures = 0;
251 		for (i = 0; i < num_child_objects; i++) {
252 			struct fsl_mc_obj_desc *obj_desc =
253 			    &child_obj_desc_array[i];
254 
255 			error = dprc_get_obj(mc_bus_dev->mc_io,
256 					     0,
257 					     mc_bus_dev->mc_handle,
258 					     i, obj_desc);
259 			if (error < 0) {
260 				dev_err(&mc_bus_dev->dev,
261 					"dprc_get_obj(i=%d) failed: %d\n",
262 					i, error);
263 				/*
264 				 * Mark the obj entry as "invalid", by using the
265 				 * empty string as obj type:
266 				 */
267 				obj_desc->type[0] = '\0';
268 				obj_desc->id = error;
269 				dprc_get_obj_failures++;
270 				continue;
271 			}
272 
273 			/*
274 			 * add a quirk for all versions of dpsec < 4.0...none
275 			 * are coherent regardless of what the MC reports.
276 			 */
277 			if ((strcmp(obj_desc->type, "dpseci") == 0) &&
278 			    (obj_desc->ver_major < 4))
279 				obj_desc->flags |=
280 					FSL_MC_OBJ_FLAG_NO_MEM_SHAREABILITY;
281 
282 			irq_count += obj_desc->irq_count;
283 			dev_dbg(&mc_bus_dev->dev,
284 				"Discovered object: type %s, id %d\n",
285 				obj_desc->type, obj_desc->id);
286 		}
287 
288 		if (dprc_get_obj_failures != 0) {
289 			dev_err(&mc_bus_dev->dev,
290 				"%d out of %d devices could not be retrieved\n",
291 				dprc_get_obj_failures, num_child_objects);
292 		}
293 	}
294 
295 	/*
296 	 * Allocate IRQ's before binding the scanned devices with their
297 	 * respective drivers.
298 	 */
299 	if (dev_get_msi_domain(&mc_bus_dev->dev) && !mc_bus->irq_resources) {
300 		if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
301 			dev_warn(&mc_bus_dev->dev,
302 				 "IRQs needed (%u) exceed IRQs preallocated (%u)\n",
303 				 irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
304 		}
305 
306 		error = fsl_mc_populate_irq_pool(mc_bus,
307 				FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
308 		if (error < 0)
309 			return error;
310 	}
311 
312 	if (total_irq_count)
313 		*total_irq_count = irq_count;
314 
315 	dprc_remove_devices(mc_bus_dev, child_obj_desc_array,
316 			    num_child_objects);
317 
318 	dprc_add_new_devices(mc_bus_dev, child_obj_desc_array,
319 			     num_child_objects);
320 
321 	if (child_obj_desc_array)
322 		devm_kfree(&mc_bus_dev->dev, child_obj_desc_array);
323 
324 	return 0;
325 }
326 
327 /**
328  * dprc_scan_container - Scans a physical DPRC and synchronizes Linux bus state
329  *
330  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
331  *
332  * Scans the physical DPRC and synchronizes the state of the Linux
333  * bus driver with the actual state of the MC by adding and removing
334  * devices as appropriate.
335  */
336 static int dprc_scan_container(struct fsl_mc_device *mc_bus_dev)
337 {
338 	int error;
339 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
340 
341 	fsl_mc_init_all_resource_pools(mc_bus_dev);
342 
343 	/*
344 	 * Discover objects in the DPRC:
345 	 */
346 	mutex_lock(&mc_bus->scan_mutex);
347 	error = dprc_scan_objects(mc_bus_dev, NULL);
348 	mutex_unlock(&mc_bus->scan_mutex);
349 	if (error < 0) {
350 		fsl_mc_cleanup_all_resource_pools(mc_bus_dev);
351 		return error;
352 	}
353 
354 	return 0;
355 }
356 
357 /**
358  * dprc_irq0_handler - Regular ISR for DPRC interrupt 0
359  *
360  * @irq: IRQ number of the interrupt being handled
361  * @arg: Pointer to device structure
362  */
363 static irqreturn_t dprc_irq0_handler(int irq_num, void *arg)
364 {
365 	return IRQ_WAKE_THREAD;
366 }
367 
368 /**
369  * dprc_irq0_handler_thread - Handler thread function for DPRC interrupt 0
370  *
371  * @irq: IRQ number of the interrupt being handled
372  * @arg: Pointer to device structure
373  */
374 static irqreturn_t dprc_irq0_handler_thread(int irq_num, void *arg)
375 {
376 	int error;
377 	u32 status;
378 	struct device *dev = arg;
379 	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
380 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
381 	struct fsl_mc_io *mc_io = mc_dev->mc_io;
382 	struct msi_desc *msi_desc = mc_dev->irqs[0]->msi_desc;
383 
384 	dev_dbg(dev, "DPRC IRQ %d triggered on CPU %u\n",
385 		irq_num, smp_processor_id());
386 
387 	if (!(mc_dev->flags & FSL_MC_IS_DPRC))
388 		return IRQ_HANDLED;
389 
390 	mutex_lock(&mc_bus->scan_mutex);
391 	if (!msi_desc || msi_desc->irq != (u32)irq_num)
392 		goto out;
393 
394 	status = 0;
395 	error = dprc_get_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
396 				    &status);
397 	if (error < 0) {
398 		dev_err(dev,
399 			"dprc_get_irq_status() failed: %d\n", error);
400 		goto out;
401 	}
402 
403 	error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
404 				      status);
405 	if (error < 0) {
406 		dev_err(dev,
407 			"dprc_clear_irq_status() failed: %d\n", error);
408 		goto out;
409 	}
410 
411 	if (status & (DPRC_IRQ_EVENT_OBJ_ADDED |
412 		      DPRC_IRQ_EVENT_OBJ_REMOVED |
413 		      DPRC_IRQ_EVENT_CONTAINER_DESTROYED |
414 		      DPRC_IRQ_EVENT_OBJ_DESTROYED |
415 		      DPRC_IRQ_EVENT_OBJ_CREATED)) {
416 		unsigned int irq_count;
417 
418 		error = dprc_scan_objects(mc_dev, &irq_count);
419 		if (error < 0) {
420 			/*
421 			 * If the error is -ENXIO, we ignore it, as it indicates
422 			 * that the object scan was aborted, as we detected that
423 			 * an object was removed from the DPRC in the MC, while
424 			 * we were scanning the DPRC.
425 			 */
426 			if (error != -ENXIO) {
427 				dev_err(dev, "dprc_scan_objects() failed: %d\n",
428 					error);
429 			}
430 
431 			goto out;
432 		}
433 
434 		if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
435 			dev_warn(dev,
436 				 "IRQs needed (%u) exceed IRQs preallocated (%u)\n",
437 				 irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
438 		}
439 	}
440 
441 out:
442 	mutex_unlock(&mc_bus->scan_mutex);
443 	return IRQ_HANDLED;
444 }
445 
446 /*
447  * Disable and clear interrupt for a given DPRC object
448  */
449 static int disable_dprc_irq(struct fsl_mc_device *mc_dev)
450 {
451 	int error;
452 	struct fsl_mc_io *mc_io = mc_dev->mc_io;
453 
454 	/*
455 	 * Disable generation of interrupt, while we configure it:
456 	 */
457 	error = dprc_set_irq_enable(mc_io, 0, mc_dev->mc_handle, 0, 0);
458 	if (error < 0) {
459 		dev_err(&mc_dev->dev,
460 			"Disabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
461 			error);
462 		return error;
463 	}
464 
465 	/*
466 	 * Disable all interrupt causes for the interrupt:
467 	 */
468 	error = dprc_set_irq_mask(mc_io, 0, mc_dev->mc_handle, 0, 0x0);
469 	if (error < 0) {
470 		dev_err(&mc_dev->dev,
471 			"Disabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
472 			error);
473 		return error;
474 	}
475 
476 	/*
477 	 * Clear any leftover interrupts:
478 	 */
479 	error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0, ~0x0U);
480 	if (error < 0) {
481 		dev_err(&mc_dev->dev,
482 			"Disabling DPRC IRQ failed: dprc_clear_irq_status() failed: %d\n",
483 			error);
484 		return error;
485 	}
486 
487 	return 0;
488 }
489 
490 static int register_dprc_irq_handler(struct fsl_mc_device *mc_dev)
491 {
492 	int error;
493 	struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
494 
495 	/*
496 	 * NOTE: devm_request_threaded_irq() invokes the device-specific
497 	 * function that programs the MSI physically in the device
498 	 */
499 	error = devm_request_threaded_irq(&mc_dev->dev,
500 					  irq->msi_desc->irq,
501 					  dprc_irq0_handler,
502 					  dprc_irq0_handler_thread,
503 					  IRQF_NO_SUSPEND | IRQF_ONESHOT,
504 					  dev_name(&mc_dev->dev),
505 					  &mc_dev->dev);
506 	if (error < 0) {
507 		dev_err(&mc_dev->dev,
508 			"devm_request_threaded_irq() failed: %d\n",
509 			error);
510 		return error;
511 	}
512 
513 	return 0;
514 }
515 
516 static int enable_dprc_irq(struct fsl_mc_device *mc_dev)
517 {
518 	int error;
519 
520 	/*
521 	 * Enable all interrupt causes for the interrupt:
522 	 */
523 	error = dprc_set_irq_mask(mc_dev->mc_io, 0, mc_dev->mc_handle, 0,
524 				  ~0x0u);
525 	if (error < 0) {
526 		dev_err(&mc_dev->dev,
527 			"Enabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
528 			error);
529 
530 		return error;
531 	}
532 
533 	/*
534 	 * Enable generation of the interrupt:
535 	 */
536 	error = dprc_set_irq_enable(mc_dev->mc_io, 0, mc_dev->mc_handle, 0, 1);
537 	if (error < 0) {
538 		dev_err(&mc_dev->dev,
539 			"Enabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
540 			error);
541 
542 		return error;
543 	}
544 
545 	return 0;
546 }
547 
548 /*
549  * Setup interrupt for a given DPRC device
550  */
551 static int dprc_setup_irq(struct fsl_mc_device *mc_dev)
552 {
553 	int error;
554 
555 	error = fsl_mc_allocate_irqs(mc_dev);
556 	if (error < 0)
557 		return error;
558 
559 	error = disable_dprc_irq(mc_dev);
560 	if (error < 0)
561 		goto error_free_irqs;
562 
563 	error = register_dprc_irq_handler(mc_dev);
564 	if (error < 0)
565 		goto error_free_irqs;
566 
567 	error = enable_dprc_irq(mc_dev);
568 	if (error < 0)
569 		goto error_free_irqs;
570 
571 	return 0;
572 
573 error_free_irqs:
574 	fsl_mc_free_irqs(mc_dev);
575 	return error;
576 }
577 
578 /**
579  * dprc_probe - callback invoked when a DPRC is being bound to this driver
580  *
581  * @mc_dev: Pointer to fsl-mc device representing a DPRC
582  *
583  * It opens the physical DPRC in the MC.
584  * It scans the DPRC to discover the MC objects contained in it.
585  * It creates the interrupt pool for the MC bus associated with the DPRC.
586  * It configures the interrupts for the DPRC device itself.
587  */
588 static int dprc_probe(struct fsl_mc_device *mc_dev)
589 {
590 	int error;
591 	size_t region_size;
592 	struct device *parent_dev = mc_dev->dev.parent;
593 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
594 	bool mc_io_created = false;
595 	bool msi_domain_set = false;
596 	u16 major_ver, minor_ver;
597 
598 	if (!is_fsl_mc_bus_dprc(mc_dev))
599 		return -EINVAL;
600 
601 	if (dev_get_msi_domain(&mc_dev->dev))
602 		return -EINVAL;
603 
604 	if (!mc_dev->mc_io) {
605 		/*
606 		 * This is a child DPRC:
607 		 */
608 		if (!dev_is_fsl_mc(parent_dev))
609 			return -EINVAL;
610 
611 		if (mc_dev->obj_desc.region_count == 0)
612 			return -EINVAL;
613 
614 		region_size = resource_size(mc_dev->regions);
615 
616 		error = fsl_create_mc_io(&mc_dev->dev,
617 					 mc_dev->regions[0].start,
618 					 region_size,
619 					 NULL,
620 					 FSL_MC_IO_ATOMIC_CONTEXT_PORTAL,
621 					 &mc_dev->mc_io);
622 		if (error < 0)
623 			return error;
624 
625 		mc_io_created = true;
626 
627 		/*
628 		 * Inherit parent MSI domain:
629 		 */
630 		dev_set_msi_domain(&mc_dev->dev,
631 				   dev_get_msi_domain(parent_dev));
632 		msi_domain_set = true;
633 	} else {
634 		/*
635 		 * This is a root DPRC
636 		 */
637 		struct irq_domain *mc_msi_domain;
638 
639 		if (dev_is_fsl_mc(parent_dev))
640 			return -EINVAL;
641 
642 		error = fsl_mc_find_msi_domain(parent_dev,
643 					       &mc_msi_domain);
644 		if (error < 0) {
645 			dev_warn(&mc_dev->dev,
646 				 "WARNING: MC bus without interrupt support\n");
647 		} else {
648 			dev_set_msi_domain(&mc_dev->dev, mc_msi_domain);
649 			msi_domain_set = true;
650 		}
651 	}
652 
653 	error = dprc_open(mc_dev->mc_io, 0, mc_dev->obj_desc.id,
654 			  &mc_dev->mc_handle);
655 	if (error < 0) {
656 		dev_err(&mc_dev->dev, "dprc_open() failed: %d\n", error);
657 		goto error_cleanup_msi_domain;
658 	}
659 
660 	error = dprc_get_attributes(mc_dev->mc_io, 0, mc_dev->mc_handle,
661 				    &mc_bus->dprc_attr);
662 	if (error < 0) {
663 		dev_err(&mc_dev->dev, "dprc_get_attributes() failed: %d\n",
664 			error);
665 		goto error_cleanup_open;
666 	}
667 
668 	error = dprc_get_api_version(mc_dev->mc_io, 0,
669 				     &major_ver,
670 				     &minor_ver);
671 	if (error < 0) {
672 		dev_err(&mc_dev->dev, "dprc_get_api_version() failed: %d\n",
673 			error);
674 		goto error_cleanup_open;
675 	}
676 
677 	if (major_ver < DPRC_MIN_VER_MAJOR ||
678 	    (major_ver == DPRC_MIN_VER_MAJOR &&
679 	     minor_ver < DPRC_MIN_VER_MINOR)) {
680 		dev_err(&mc_dev->dev,
681 			"ERROR: DPRC version %d.%d not supported\n",
682 			major_ver, minor_ver);
683 		error = -ENOTSUPP;
684 		goto error_cleanup_open;
685 	}
686 
687 	mutex_init(&mc_bus->scan_mutex);
688 
689 	/*
690 	 * Discover MC objects in DPRC object:
691 	 */
692 	error = dprc_scan_container(mc_dev);
693 	if (error < 0)
694 		goto error_cleanup_open;
695 
696 	/*
697 	 * Configure interrupt for the DPRC object associated with this MC bus:
698 	 */
699 	error = dprc_setup_irq(mc_dev);
700 	if (error < 0)
701 		goto error_cleanup_open;
702 
703 	dev_info(&mc_dev->dev, "DPRC device bound to driver");
704 	return 0;
705 
706 error_cleanup_open:
707 	(void)dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
708 
709 error_cleanup_msi_domain:
710 	if (msi_domain_set)
711 		dev_set_msi_domain(&mc_dev->dev, NULL);
712 
713 	if (mc_io_created) {
714 		fsl_destroy_mc_io(mc_dev->mc_io);
715 		mc_dev->mc_io = NULL;
716 	}
717 
718 	return error;
719 }
720 
721 /*
722  * Tear down interrupt for a given DPRC object
723  */
724 static void dprc_teardown_irq(struct fsl_mc_device *mc_dev)
725 {
726 	struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
727 
728 	(void)disable_dprc_irq(mc_dev);
729 
730 	devm_free_irq(&mc_dev->dev, irq->msi_desc->irq, &mc_dev->dev);
731 
732 	fsl_mc_free_irqs(mc_dev);
733 }
734 
735 /**
736  * dprc_remove - callback invoked when a DPRC is being unbound from this driver
737  *
738  * @mc_dev: Pointer to fsl-mc device representing the DPRC
739  *
740  * It removes the DPRC's child objects from Linux (not from the MC) and
741  * closes the DPRC device in the MC.
742  * It tears down the interrupts that were configured for the DPRC device.
743  * It destroys the interrupt pool associated with this MC bus.
744  */
745 static int dprc_remove(struct fsl_mc_device *mc_dev)
746 {
747 	int error;
748 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
749 
750 	if (!is_fsl_mc_bus_dprc(mc_dev))
751 		return -EINVAL;
752 	if (!mc_dev->mc_io)
753 		return -EINVAL;
754 
755 	if (!mc_bus->irq_resources)
756 		return -EINVAL;
757 
758 	if (dev_get_msi_domain(&mc_dev->dev))
759 		dprc_teardown_irq(mc_dev);
760 
761 	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
762 
763 	if (dev_get_msi_domain(&mc_dev->dev)) {
764 		fsl_mc_cleanup_irq_pool(mc_bus);
765 		dev_set_msi_domain(&mc_dev->dev, NULL);
766 	}
767 
768 	fsl_mc_cleanup_all_resource_pools(mc_dev);
769 
770 	error = dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
771 	if (error < 0)
772 		dev_err(&mc_dev->dev, "dprc_close() failed: %d\n", error);
773 
774 	if (!fsl_mc_is_root_dprc(&mc_dev->dev)) {
775 		fsl_destroy_mc_io(mc_dev->mc_io);
776 		mc_dev->mc_io = NULL;
777 	}
778 
779 	dev_info(&mc_dev->dev, "DPRC device unbound from driver");
780 	return 0;
781 }
782 
783 static const struct fsl_mc_device_id match_id_table[] = {
784 	{
785 	 .vendor = FSL_MC_VENDOR_FREESCALE,
786 	 .obj_type = "dprc"},
787 	{.vendor = 0x0},
788 };
789 
790 static struct fsl_mc_driver dprc_driver = {
791 	.driver = {
792 		   .name = FSL_MC_DPRC_DRIVER_NAME,
793 		   .owner = THIS_MODULE,
794 		   .pm = NULL,
795 		   },
796 	.match_id_table = match_id_table,
797 	.probe = dprc_probe,
798 	.remove = dprc_remove,
799 };
800 
801 int __init dprc_driver_init(void)
802 {
803 	return fsl_mc_driver_register(&dprc_driver);
804 }
805 
806 void dprc_driver_exit(void)
807 {
808 	fsl_mc_driver_unregister(&dprc_driver);
809 }
810