xref: /openbmc/linux/drivers/bus/fsl-mc/dprc-driver.c (revision 715f23b6)
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 struct fsl_mc_device *fsl_mc_device_lookup(struct fsl_mc_obj_desc *obj_desc,
108 					   struct fsl_mc_device *mc_bus_dev)
109 {
110 	struct device *dev;
111 
112 	dev = device_find_child(&mc_bus_dev->dev, obj_desc,
113 				__fsl_mc_device_match);
114 
115 	return dev ? to_fsl_mc_device(dev) : NULL;
116 }
117 
118 /**
119  * check_plugged_state_change - Check change in an MC object's plugged state
120  *
121  * @mc_dev: pointer to the fsl-mc device for a given MC object
122  * @obj_desc: pointer to the MC object's descriptor in the MC
123  *
124  * If the plugged state has changed from unplugged to plugged, the fsl-mc
125  * device is bound to the corresponding device driver.
126  * If the plugged state has changed from plugged to unplugged, the fsl-mc
127  * device is unbound from the corresponding device driver.
128  */
129 static void check_plugged_state_change(struct fsl_mc_device *mc_dev,
130 				       struct fsl_mc_obj_desc *obj_desc)
131 {
132 	int error;
133 	u32 plugged_flag_at_mc =
134 			obj_desc->state & FSL_MC_OBJ_STATE_PLUGGED;
135 
136 	if (plugged_flag_at_mc !=
137 	    (mc_dev->obj_desc.state & FSL_MC_OBJ_STATE_PLUGGED)) {
138 		if (plugged_flag_at_mc) {
139 			mc_dev->obj_desc.state |= FSL_MC_OBJ_STATE_PLUGGED;
140 			error = device_attach(&mc_dev->dev);
141 			if (error < 0) {
142 				dev_err(&mc_dev->dev,
143 					"device_attach() failed: %d\n",
144 					error);
145 			}
146 		} else {
147 			mc_dev->obj_desc.state &= ~FSL_MC_OBJ_STATE_PLUGGED;
148 			device_release_driver(&mc_dev->dev);
149 		}
150 	}
151 }
152 
153 /**
154  * dprc_add_new_devices - Adds devices to the logical bus for a DPRC
155  *
156  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
157  * @obj_desc_array: array of device descriptors for child devices currently
158  * present in the physical DPRC.
159  * @num_child_objects_in_mc: number of entries in obj_desc_array
160  *
161  * Synchronizes the state of the Linux bus driver with the actual
162  * state of the MC by adding objects that have been newly discovered
163  * in the physical DPRC.
164  */
165 static void dprc_add_new_devices(struct fsl_mc_device *mc_bus_dev,
166 				 struct fsl_mc_obj_desc *obj_desc_array,
167 				 int num_child_objects_in_mc)
168 {
169 	int error;
170 	int i;
171 
172 	for (i = 0; i < num_child_objects_in_mc; i++) {
173 		struct fsl_mc_device *child_dev;
174 		struct fsl_mc_obj_desc *obj_desc = &obj_desc_array[i];
175 
176 		if (strlen(obj_desc->type) == 0)
177 			continue;
178 
179 		/*
180 		 * Check if device is already known to Linux:
181 		 */
182 		child_dev = fsl_mc_device_lookup(obj_desc, mc_bus_dev);
183 		if (child_dev) {
184 			check_plugged_state_change(child_dev, obj_desc);
185 			put_device(&child_dev->dev);
186 			continue;
187 		}
188 
189 		error = fsl_mc_device_add(obj_desc, NULL, &mc_bus_dev->dev,
190 					  &child_dev);
191 		if (error < 0)
192 			continue;
193 	}
194 }
195 
196 /**
197  * dprc_scan_objects - Discover objects in a DPRC
198  *
199  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
200  * @total_irq_count: If argument is provided the function populates the
201  * total number of IRQs created by objects in the DPRC.
202  *
203  * Detects objects added and removed from a DPRC and synchronizes the
204  * state of the Linux bus driver, MC by adding and removing
205  * devices accordingly.
206  * Two types of devices can be found in a DPRC: allocatable objects (e.g.,
207  * dpbp, dpmcp) and non-allocatable devices (e.g., dprc, dpni).
208  * All allocatable devices needed to be probed before all non-allocatable
209  * devices, to ensure that device drivers for non-allocatable
210  * devices can allocate any type of allocatable devices.
211  * That is, we need to ensure that the corresponding resource pools are
212  * populated before they can get allocation requests from probe callbacks
213  * of the device drivers for the non-allocatable devices.
214  */
215 static int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
216 			     unsigned int *total_irq_count)
217 {
218 	int num_child_objects;
219 	int dprc_get_obj_failures;
220 	int error;
221 	unsigned int irq_count = mc_bus_dev->obj_desc.irq_count;
222 	struct fsl_mc_obj_desc *child_obj_desc_array = NULL;
223 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
224 
225 	error = dprc_get_obj_count(mc_bus_dev->mc_io,
226 				   0,
227 				   mc_bus_dev->mc_handle,
228 				   &num_child_objects);
229 	if (error < 0) {
230 		dev_err(&mc_bus_dev->dev, "dprc_get_obj_count() failed: %d\n",
231 			error);
232 		return error;
233 	}
234 
235 	if (num_child_objects != 0) {
236 		int i;
237 
238 		child_obj_desc_array =
239 		    devm_kmalloc_array(&mc_bus_dev->dev, num_child_objects,
240 				       sizeof(*child_obj_desc_array),
241 				       GFP_KERNEL);
242 		if (!child_obj_desc_array)
243 			return -ENOMEM;
244 
245 		/*
246 		 * Discover objects currently present in the physical DPRC:
247 		 */
248 		dprc_get_obj_failures = 0;
249 		for (i = 0; i < num_child_objects; i++) {
250 			struct fsl_mc_obj_desc *obj_desc =
251 			    &child_obj_desc_array[i];
252 
253 			error = dprc_get_obj(mc_bus_dev->mc_io,
254 					     0,
255 					     mc_bus_dev->mc_handle,
256 					     i, obj_desc);
257 			if (error < 0) {
258 				dev_err(&mc_bus_dev->dev,
259 					"dprc_get_obj(i=%d) failed: %d\n",
260 					i, error);
261 				/*
262 				 * Mark the obj entry as "invalid", by using the
263 				 * empty string as obj type:
264 				 */
265 				obj_desc->type[0] = '\0';
266 				obj_desc->id = error;
267 				dprc_get_obj_failures++;
268 				continue;
269 			}
270 
271 			/*
272 			 * add a quirk for all versions of dpsec < 4.0...none
273 			 * are coherent regardless of what the MC reports.
274 			 */
275 			if ((strcmp(obj_desc->type, "dpseci") == 0) &&
276 			    (obj_desc->ver_major < 4))
277 				obj_desc->flags |=
278 					FSL_MC_OBJ_FLAG_NO_MEM_SHAREABILITY;
279 
280 			irq_count += obj_desc->irq_count;
281 			dev_dbg(&mc_bus_dev->dev,
282 				"Discovered object: type %s, id %d\n",
283 				obj_desc->type, obj_desc->id);
284 		}
285 
286 		if (dprc_get_obj_failures != 0) {
287 			dev_err(&mc_bus_dev->dev,
288 				"%d out of %d devices could not be retrieved\n",
289 				dprc_get_obj_failures, num_child_objects);
290 		}
291 	}
292 
293 	/*
294 	 * Allocate IRQ's before binding the scanned devices with their
295 	 * respective drivers.
296 	 */
297 	if (dev_get_msi_domain(&mc_bus_dev->dev) && !mc_bus->irq_resources) {
298 		if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
299 			dev_warn(&mc_bus_dev->dev,
300 				 "IRQs needed (%u) exceed IRQs preallocated (%u)\n",
301 				 irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
302 		}
303 
304 		error = fsl_mc_populate_irq_pool(mc_bus,
305 				FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
306 		if (error < 0)
307 			return error;
308 	}
309 
310 	if (total_irq_count)
311 		*total_irq_count = irq_count;
312 
313 	dprc_remove_devices(mc_bus_dev, child_obj_desc_array,
314 			    num_child_objects);
315 
316 	dprc_add_new_devices(mc_bus_dev, child_obj_desc_array,
317 			     num_child_objects);
318 
319 	if (child_obj_desc_array)
320 		devm_kfree(&mc_bus_dev->dev, child_obj_desc_array);
321 
322 	return 0;
323 }
324 
325 /**
326  * dprc_scan_container - Scans a physical DPRC and synchronizes Linux bus state
327  *
328  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
329  *
330  * Scans the physical DPRC and synchronizes the state of the Linux
331  * bus driver with the actual state of the MC by adding and removing
332  * devices as appropriate.
333  */
334 static int dprc_scan_container(struct fsl_mc_device *mc_bus_dev)
335 {
336 	int error;
337 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
338 
339 	fsl_mc_init_all_resource_pools(mc_bus_dev);
340 
341 	/*
342 	 * Discover objects in the DPRC:
343 	 */
344 	mutex_lock(&mc_bus->scan_mutex);
345 	error = dprc_scan_objects(mc_bus_dev, NULL);
346 	mutex_unlock(&mc_bus->scan_mutex);
347 	if (error < 0) {
348 		fsl_mc_cleanup_all_resource_pools(mc_bus_dev);
349 		return error;
350 	}
351 
352 	return 0;
353 }
354 
355 /**
356  * dprc_irq0_handler - Regular ISR for DPRC interrupt 0
357  *
358  * @irq: IRQ number of the interrupt being handled
359  * @arg: Pointer to device structure
360  */
361 static irqreturn_t dprc_irq0_handler(int irq_num, void *arg)
362 {
363 	return IRQ_WAKE_THREAD;
364 }
365 
366 /**
367  * dprc_irq0_handler_thread - Handler thread function for DPRC interrupt 0
368  *
369  * @irq: IRQ number of the interrupt being handled
370  * @arg: Pointer to device structure
371  */
372 static irqreturn_t dprc_irq0_handler_thread(int irq_num, void *arg)
373 {
374 	int error;
375 	u32 status;
376 	struct device *dev = arg;
377 	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
378 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
379 	struct fsl_mc_io *mc_io = mc_dev->mc_io;
380 	struct msi_desc *msi_desc = mc_dev->irqs[0]->msi_desc;
381 
382 	dev_dbg(dev, "DPRC IRQ %d triggered on CPU %u\n",
383 		irq_num, smp_processor_id());
384 
385 	if (!(mc_dev->flags & FSL_MC_IS_DPRC))
386 		return IRQ_HANDLED;
387 
388 	mutex_lock(&mc_bus->scan_mutex);
389 	if (!msi_desc || msi_desc->irq != (u32)irq_num)
390 		goto out;
391 
392 	status = 0;
393 	error = dprc_get_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
394 				    &status);
395 	if (error < 0) {
396 		dev_err(dev,
397 			"dprc_get_irq_status() failed: %d\n", error);
398 		goto out;
399 	}
400 
401 	error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
402 				      status);
403 	if (error < 0) {
404 		dev_err(dev,
405 			"dprc_clear_irq_status() failed: %d\n", error);
406 		goto out;
407 	}
408 
409 	if (status & (DPRC_IRQ_EVENT_OBJ_ADDED |
410 		      DPRC_IRQ_EVENT_OBJ_REMOVED |
411 		      DPRC_IRQ_EVENT_CONTAINER_DESTROYED |
412 		      DPRC_IRQ_EVENT_OBJ_DESTROYED |
413 		      DPRC_IRQ_EVENT_OBJ_CREATED)) {
414 		unsigned int irq_count;
415 
416 		error = dprc_scan_objects(mc_dev, &irq_count);
417 		if (error < 0) {
418 			/*
419 			 * If the error is -ENXIO, we ignore it, as it indicates
420 			 * that the object scan was aborted, as we detected that
421 			 * an object was removed from the DPRC in the MC, while
422 			 * we were scanning the DPRC.
423 			 */
424 			if (error != -ENXIO) {
425 				dev_err(dev, "dprc_scan_objects() failed: %d\n",
426 					error);
427 			}
428 
429 			goto out;
430 		}
431 
432 		if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
433 			dev_warn(dev,
434 				 "IRQs needed (%u) exceed IRQs preallocated (%u)\n",
435 				 irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
436 		}
437 	}
438 
439 out:
440 	mutex_unlock(&mc_bus->scan_mutex);
441 	return IRQ_HANDLED;
442 }
443 
444 /*
445  * Disable and clear interrupt for a given DPRC object
446  */
447 static int disable_dprc_irq(struct fsl_mc_device *mc_dev)
448 {
449 	int error;
450 	struct fsl_mc_io *mc_io = mc_dev->mc_io;
451 
452 	/*
453 	 * Disable generation of interrupt, while we configure it:
454 	 */
455 	error = dprc_set_irq_enable(mc_io, 0, mc_dev->mc_handle, 0, 0);
456 	if (error < 0) {
457 		dev_err(&mc_dev->dev,
458 			"Disabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
459 			error);
460 		return error;
461 	}
462 
463 	/*
464 	 * Disable all interrupt causes for the interrupt:
465 	 */
466 	error = dprc_set_irq_mask(mc_io, 0, mc_dev->mc_handle, 0, 0x0);
467 	if (error < 0) {
468 		dev_err(&mc_dev->dev,
469 			"Disabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
470 			error);
471 		return error;
472 	}
473 
474 	/*
475 	 * Clear any leftover interrupts:
476 	 */
477 	error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0, ~0x0U);
478 	if (error < 0) {
479 		dev_err(&mc_dev->dev,
480 			"Disabling DPRC IRQ failed: dprc_clear_irq_status() failed: %d\n",
481 			error);
482 		return error;
483 	}
484 
485 	return 0;
486 }
487 
488 static int register_dprc_irq_handler(struct fsl_mc_device *mc_dev)
489 {
490 	int error;
491 	struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
492 
493 	/*
494 	 * NOTE: devm_request_threaded_irq() invokes the device-specific
495 	 * function that programs the MSI physically in the device
496 	 */
497 	error = devm_request_threaded_irq(&mc_dev->dev,
498 					  irq->msi_desc->irq,
499 					  dprc_irq0_handler,
500 					  dprc_irq0_handler_thread,
501 					  IRQF_NO_SUSPEND | IRQF_ONESHOT,
502 					  dev_name(&mc_dev->dev),
503 					  &mc_dev->dev);
504 	if (error < 0) {
505 		dev_err(&mc_dev->dev,
506 			"devm_request_threaded_irq() failed: %d\n",
507 			error);
508 		return error;
509 	}
510 
511 	return 0;
512 }
513 
514 static int enable_dprc_irq(struct fsl_mc_device *mc_dev)
515 {
516 	int error;
517 
518 	/*
519 	 * Enable all interrupt causes for the interrupt:
520 	 */
521 	error = dprc_set_irq_mask(mc_dev->mc_io, 0, mc_dev->mc_handle, 0,
522 				  ~0x0u);
523 	if (error < 0) {
524 		dev_err(&mc_dev->dev,
525 			"Enabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
526 			error);
527 
528 		return error;
529 	}
530 
531 	/*
532 	 * Enable generation of the interrupt:
533 	 */
534 	error = dprc_set_irq_enable(mc_dev->mc_io, 0, mc_dev->mc_handle, 0, 1);
535 	if (error < 0) {
536 		dev_err(&mc_dev->dev,
537 			"Enabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
538 			error);
539 
540 		return error;
541 	}
542 
543 	return 0;
544 }
545 
546 /*
547  * Setup interrupt for a given DPRC device
548  */
549 static int dprc_setup_irq(struct fsl_mc_device *mc_dev)
550 {
551 	int error;
552 
553 	error = fsl_mc_allocate_irqs(mc_dev);
554 	if (error < 0)
555 		return error;
556 
557 	error = disable_dprc_irq(mc_dev);
558 	if (error < 0)
559 		goto error_free_irqs;
560 
561 	error = register_dprc_irq_handler(mc_dev);
562 	if (error < 0)
563 		goto error_free_irqs;
564 
565 	error = enable_dprc_irq(mc_dev);
566 	if (error < 0)
567 		goto error_free_irqs;
568 
569 	return 0;
570 
571 error_free_irqs:
572 	fsl_mc_free_irqs(mc_dev);
573 	return error;
574 }
575 
576 /**
577  * dprc_probe - callback invoked when a DPRC is being bound to this driver
578  *
579  * @mc_dev: Pointer to fsl-mc device representing a DPRC
580  *
581  * It opens the physical DPRC in the MC.
582  * It scans the DPRC to discover the MC objects contained in it.
583  * It creates the interrupt pool for the MC bus associated with the DPRC.
584  * It configures the interrupts for the DPRC device itself.
585  */
586 static int dprc_probe(struct fsl_mc_device *mc_dev)
587 {
588 	int error;
589 	size_t region_size;
590 	struct device *parent_dev = mc_dev->dev.parent;
591 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
592 	bool mc_io_created = false;
593 	bool msi_domain_set = false;
594 	u16 major_ver, minor_ver;
595 
596 	if (!is_fsl_mc_bus_dprc(mc_dev))
597 		return -EINVAL;
598 
599 	if (dev_get_msi_domain(&mc_dev->dev))
600 		return -EINVAL;
601 
602 	if (!mc_dev->mc_io) {
603 		/*
604 		 * This is a child DPRC:
605 		 */
606 		if (!dev_is_fsl_mc(parent_dev))
607 			return -EINVAL;
608 
609 		if (mc_dev->obj_desc.region_count == 0)
610 			return -EINVAL;
611 
612 		region_size = resource_size(mc_dev->regions);
613 
614 		error = fsl_create_mc_io(&mc_dev->dev,
615 					 mc_dev->regions[0].start,
616 					 region_size,
617 					 NULL,
618 					 FSL_MC_IO_ATOMIC_CONTEXT_PORTAL,
619 					 &mc_dev->mc_io);
620 		if (error < 0)
621 			return error;
622 
623 		mc_io_created = true;
624 
625 		/*
626 		 * Inherit parent MSI domain:
627 		 */
628 		dev_set_msi_domain(&mc_dev->dev,
629 				   dev_get_msi_domain(parent_dev));
630 		msi_domain_set = true;
631 	} else {
632 		/*
633 		 * This is a root DPRC
634 		 */
635 		struct irq_domain *mc_msi_domain;
636 
637 		if (dev_is_fsl_mc(parent_dev))
638 			return -EINVAL;
639 
640 		error = fsl_mc_find_msi_domain(parent_dev,
641 					       &mc_msi_domain);
642 		if (error < 0) {
643 			dev_warn(&mc_dev->dev,
644 				 "WARNING: MC bus without interrupt support\n");
645 		} else {
646 			dev_set_msi_domain(&mc_dev->dev, mc_msi_domain);
647 			msi_domain_set = true;
648 		}
649 	}
650 
651 	error = dprc_open(mc_dev->mc_io, 0, mc_dev->obj_desc.id,
652 			  &mc_dev->mc_handle);
653 	if (error < 0) {
654 		dev_err(&mc_dev->dev, "dprc_open() failed: %d\n", error);
655 		goto error_cleanup_msi_domain;
656 	}
657 
658 	error = dprc_get_attributes(mc_dev->mc_io, 0, mc_dev->mc_handle,
659 				    &mc_bus->dprc_attr);
660 	if (error < 0) {
661 		dev_err(&mc_dev->dev, "dprc_get_attributes() failed: %d\n",
662 			error);
663 		goto error_cleanup_open;
664 	}
665 
666 	error = dprc_get_api_version(mc_dev->mc_io, 0,
667 				     &major_ver,
668 				     &minor_ver);
669 	if (error < 0) {
670 		dev_err(&mc_dev->dev, "dprc_get_api_version() failed: %d\n",
671 			error);
672 		goto error_cleanup_open;
673 	}
674 
675 	if (major_ver < DPRC_MIN_VER_MAJOR ||
676 	    (major_ver == DPRC_MIN_VER_MAJOR &&
677 	     minor_ver < DPRC_MIN_VER_MINOR)) {
678 		dev_err(&mc_dev->dev,
679 			"ERROR: DPRC version %d.%d not supported\n",
680 			major_ver, minor_ver);
681 		error = -ENOTSUPP;
682 		goto error_cleanup_open;
683 	}
684 
685 	mutex_init(&mc_bus->scan_mutex);
686 
687 	/*
688 	 * Discover MC objects in DPRC object:
689 	 */
690 	error = dprc_scan_container(mc_dev);
691 	if (error < 0)
692 		goto error_cleanup_open;
693 
694 	/*
695 	 * Configure interrupt for the DPRC object associated with this MC bus:
696 	 */
697 	error = dprc_setup_irq(mc_dev);
698 	if (error < 0)
699 		goto error_cleanup_open;
700 
701 	dev_info(&mc_dev->dev, "DPRC device bound to driver");
702 	return 0;
703 
704 error_cleanup_open:
705 	(void)dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
706 
707 error_cleanup_msi_domain:
708 	if (msi_domain_set)
709 		dev_set_msi_domain(&mc_dev->dev, NULL);
710 
711 	if (mc_io_created) {
712 		fsl_destroy_mc_io(mc_dev->mc_io);
713 		mc_dev->mc_io = NULL;
714 	}
715 
716 	return error;
717 }
718 
719 /*
720  * Tear down interrupt for a given DPRC object
721  */
722 static void dprc_teardown_irq(struct fsl_mc_device *mc_dev)
723 {
724 	struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
725 
726 	(void)disable_dprc_irq(mc_dev);
727 
728 	devm_free_irq(&mc_dev->dev, irq->msi_desc->irq, &mc_dev->dev);
729 
730 	fsl_mc_free_irqs(mc_dev);
731 }
732 
733 /**
734  * dprc_remove - callback invoked when a DPRC is being unbound from this driver
735  *
736  * @mc_dev: Pointer to fsl-mc device representing the DPRC
737  *
738  * It removes the DPRC's child objects from Linux (not from the MC) and
739  * closes the DPRC device in the MC.
740  * It tears down the interrupts that were configured for the DPRC device.
741  * It destroys the interrupt pool associated with this MC bus.
742  */
743 static int dprc_remove(struct fsl_mc_device *mc_dev)
744 {
745 	int error;
746 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
747 
748 	if (!is_fsl_mc_bus_dprc(mc_dev))
749 		return -EINVAL;
750 	if (!mc_dev->mc_io)
751 		return -EINVAL;
752 
753 	if (!mc_bus->irq_resources)
754 		return -EINVAL;
755 
756 	if (dev_get_msi_domain(&mc_dev->dev))
757 		dprc_teardown_irq(mc_dev);
758 
759 	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
760 
761 	if (dev_get_msi_domain(&mc_dev->dev)) {
762 		fsl_mc_cleanup_irq_pool(mc_bus);
763 		dev_set_msi_domain(&mc_dev->dev, NULL);
764 	}
765 
766 	fsl_mc_cleanup_all_resource_pools(mc_dev);
767 
768 	error = dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
769 	if (error < 0)
770 		dev_err(&mc_dev->dev, "dprc_close() failed: %d\n", error);
771 
772 	if (!fsl_mc_is_root_dprc(&mc_dev->dev)) {
773 		fsl_destroy_mc_io(mc_dev->mc_io);
774 		mc_dev->mc_io = NULL;
775 	}
776 
777 	dev_info(&mc_dev->dev, "DPRC device unbound from driver");
778 	return 0;
779 }
780 
781 static const struct fsl_mc_device_id match_id_table[] = {
782 	{
783 	 .vendor = FSL_MC_VENDOR_FREESCALE,
784 	 .obj_type = "dprc"},
785 	{.vendor = 0x0},
786 };
787 
788 static struct fsl_mc_driver dprc_driver = {
789 	.driver = {
790 		   .name = FSL_MC_DPRC_DRIVER_NAME,
791 		   .owner = THIS_MODULE,
792 		   .pm = NULL,
793 		   },
794 	.match_id_table = match_id_table,
795 	.probe = dprc_probe,
796 	.remove = dprc_remove,
797 };
798 
799 int __init dprc_driver_init(void)
800 {
801 	return fsl_mc_driver_register(&dprc_driver);
802 }
803 
804 void dprc_driver_exit(void)
805 {
806 	fsl_mc_driver_unregister(&dprc_driver);
807 }
808