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 
fsl_mc_device_match(struct fsl_mc_device * mc_dev,struct fsl_mc_obj_desc * obj_desc)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 
fsl_mc_obj_desc_is_allocatable(struct fsl_mc_obj_desc * obj)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 
__fsl_mc_device_remove_if_not_in_mc(struct device * dev,void * data)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 
__fsl_mc_device_remove(struct device * dev,void * data)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  */
dprc_remove_devices(struct fsl_mc_device * mc_bus_dev,struct fsl_mc_obj_desc * obj_desc_array,int num_child_objects_in_mc)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 
__fsl_mc_device_match(struct device * dev,void * data)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 
fsl_mc_device_lookup(struct fsl_mc_obj_desc * obj_desc,struct fsl_mc_device * mc_bus_dev)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  */
check_plugged_state_change(struct fsl_mc_device * mc_dev,struct fsl_mc_obj_desc * obj_desc)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 
fsl_mc_obj_device_add(struct fsl_mc_device * mc_bus_dev,struct fsl_mc_obj_desc * obj_desc)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  */
dprc_add_new_devices(struct fsl_mc_device * mc_bus_dev,struct fsl_mc_obj_desc * obj_desc_array,int num_child_objects_in_mc)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  */
dprc_scan_objects(struct fsl_mc_device * mc_bus_dev,bool alloc_interrupts)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  * @alloc_interrupts: if true the function allocates the interrupt pool,
354  *                    otherwise the interrupt allocation is delayed
355  * Scans the physical DPRC and synchronizes the state of the Linux
356  * bus driver with the actual state of the MC by adding and removing
357  * devices as appropriate.
358  */
dprc_scan_container(struct fsl_mc_device * mc_bus_dev,bool alloc_interrupts)359 int dprc_scan_container(struct fsl_mc_device *mc_bus_dev,
360 			bool alloc_interrupts)
361 {
362 	int error = 0;
363 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
364 
365 	fsl_mc_init_all_resource_pools(mc_bus_dev);
366 
367 	/*
368 	 * Discover objects in the DPRC:
369 	 */
370 	mutex_lock(&mc_bus->scan_mutex);
371 	error = dprc_scan_objects(mc_bus_dev, alloc_interrupts);
372 	mutex_unlock(&mc_bus->scan_mutex);
373 
374 	return error;
375 }
376 EXPORT_SYMBOL_GPL(dprc_scan_container);
377 
378 /**
379  * dprc_irq0_handler - Regular ISR for DPRC interrupt 0
380  *
381  * @irq_num: IRQ number of the interrupt being handled
382  * @arg: Pointer to device structure
383  */
dprc_irq0_handler(int irq_num,void * arg)384 static irqreturn_t dprc_irq0_handler(int irq_num, void *arg)
385 {
386 	return IRQ_WAKE_THREAD;
387 }
388 
389 /**
390  * dprc_irq0_handler_thread - Handler thread function for DPRC interrupt 0
391  *
392  * @irq_num: IRQ number of the interrupt being handled
393  * @arg: Pointer to device structure
394  */
dprc_irq0_handler_thread(int irq_num,void * arg)395 static irqreturn_t dprc_irq0_handler_thread(int irq_num, void *arg)
396 {
397 	int error;
398 	u32 status;
399 	struct device *dev = arg;
400 	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
401 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
402 	struct fsl_mc_io *mc_io = mc_dev->mc_io;
403 	struct msi_desc *msi_desc = mc_dev->irqs[0]->msi_desc;
404 
405 	dev_dbg(dev, "DPRC IRQ %d triggered on CPU %u\n",
406 		irq_num, smp_processor_id());
407 
408 	if (!(mc_dev->flags & FSL_MC_IS_DPRC))
409 		return IRQ_HANDLED;
410 
411 	mutex_lock(&mc_bus->scan_mutex);
412 	if (!msi_desc || msi_desc->irq != (u32)irq_num)
413 		goto out;
414 
415 	status = 0;
416 	error = dprc_get_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
417 				    &status);
418 	if (error < 0) {
419 		dev_err(dev,
420 			"dprc_get_irq_status() failed: %d\n", error);
421 		goto out;
422 	}
423 
424 	error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
425 				      status);
426 	if (error < 0) {
427 		dev_err(dev,
428 			"dprc_clear_irq_status() failed: %d\n", error);
429 		goto out;
430 	}
431 
432 	if (status & (DPRC_IRQ_EVENT_OBJ_ADDED |
433 		      DPRC_IRQ_EVENT_OBJ_REMOVED |
434 		      DPRC_IRQ_EVENT_CONTAINER_DESTROYED |
435 		      DPRC_IRQ_EVENT_OBJ_DESTROYED |
436 		      DPRC_IRQ_EVENT_OBJ_CREATED)) {
437 
438 		error = dprc_scan_objects(mc_dev, true);
439 		if (error < 0) {
440 			/*
441 			 * If the error is -ENXIO, we ignore it, as it indicates
442 			 * that the object scan was aborted, as we detected that
443 			 * an object was removed from the DPRC in the MC, while
444 			 * we were scanning the DPRC.
445 			 */
446 			if (error != -ENXIO) {
447 				dev_err(dev, "dprc_scan_objects() failed: %d\n",
448 					error);
449 			}
450 
451 			goto out;
452 		}
453 	}
454 
455 out:
456 	mutex_unlock(&mc_bus->scan_mutex);
457 	return IRQ_HANDLED;
458 }
459 
460 /*
461  * Disable and clear interrupt for a given DPRC object
462  */
disable_dprc_irq(struct fsl_mc_device * mc_dev)463 int disable_dprc_irq(struct fsl_mc_device *mc_dev)
464 {
465 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
466 	int error;
467 	struct fsl_mc_io *mc_io = mc_dev->mc_io;
468 
469 	/*
470 	 * Disable generation of interrupt, while we configure it:
471 	 */
472 	error = dprc_set_irq_enable(mc_io, 0, mc_dev->mc_handle, 0, 0);
473 	if (error < 0) {
474 		dev_err(&mc_dev->dev,
475 			"Disabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
476 			error);
477 		return error;
478 	}
479 
480 	/*
481 	 * Disable all interrupt causes for the interrupt:
482 	 */
483 	error = dprc_set_irq_mask(mc_io, 0, mc_dev->mc_handle, 0, 0x0);
484 	if (error < 0) {
485 		dev_err(&mc_dev->dev,
486 			"Disabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
487 			error);
488 		return error;
489 	}
490 
491 	/*
492 	 * Clear any leftover interrupts:
493 	 */
494 	error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0, ~0x0U);
495 	if (error < 0) {
496 		dev_err(&mc_dev->dev,
497 			"Disabling DPRC IRQ failed: dprc_clear_irq_status() failed: %d\n",
498 			error);
499 		return error;
500 	}
501 
502 	mc_bus->irq_enabled = 0;
503 
504 	return 0;
505 }
506 
get_dprc_irq_state(struct fsl_mc_device * mc_dev)507 int get_dprc_irq_state(struct fsl_mc_device *mc_dev)
508 {
509 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
510 
511 	return mc_bus->irq_enabled;
512 }
513 
register_dprc_irq_handler(struct fsl_mc_device * mc_dev)514 static int register_dprc_irq_handler(struct fsl_mc_device *mc_dev)
515 {
516 	int error;
517 	struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
518 
519 	/*
520 	 * NOTE: devm_request_threaded_irq() invokes the device-specific
521 	 * function that programs the MSI physically in the device
522 	 */
523 	error = devm_request_threaded_irq(&mc_dev->dev,
524 					  irq->msi_desc->irq,
525 					  dprc_irq0_handler,
526 					  dprc_irq0_handler_thread,
527 					  IRQF_NO_SUSPEND | IRQF_ONESHOT,
528 					  dev_name(&mc_dev->dev),
529 					  &mc_dev->dev);
530 	if (error < 0) {
531 		dev_err(&mc_dev->dev,
532 			"devm_request_threaded_irq() failed: %d\n",
533 			error);
534 		return error;
535 	}
536 
537 	return 0;
538 }
539 
enable_dprc_irq(struct fsl_mc_device * mc_dev)540 int enable_dprc_irq(struct fsl_mc_device *mc_dev)
541 {
542 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
543 	int error;
544 
545 	/*
546 	 * Enable all interrupt causes for the interrupt:
547 	 */
548 	error = dprc_set_irq_mask(mc_dev->mc_io, 0, mc_dev->mc_handle, 0,
549 				  ~0x0u);
550 	if (error < 0) {
551 		dev_err(&mc_dev->dev,
552 			"Enabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
553 			error);
554 
555 		return error;
556 	}
557 
558 	/*
559 	 * Enable generation of the interrupt:
560 	 */
561 	error = dprc_set_irq_enable(mc_dev->mc_io, 0, mc_dev->mc_handle, 0, 1);
562 	if (error < 0) {
563 		dev_err(&mc_dev->dev,
564 			"Enabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
565 			error);
566 
567 		return error;
568 	}
569 
570 	mc_bus->irq_enabled = 1;
571 
572 	return 0;
573 }
574 
575 /*
576  * Setup interrupt for a given DPRC device
577  */
dprc_setup_irq(struct fsl_mc_device * mc_dev)578 static int dprc_setup_irq(struct fsl_mc_device *mc_dev)
579 {
580 	int error;
581 
582 	error = fsl_mc_allocate_irqs(mc_dev);
583 	if (error < 0)
584 		return error;
585 
586 	error = disable_dprc_irq(mc_dev);
587 	if (error < 0)
588 		goto error_free_irqs;
589 
590 	error = register_dprc_irq_handler(mc_dev);
591 	if (error < 0)
592 		goto error_free_irqs;
593 
594 	error = enable_dprc_irq(mc_dev);
595 	if (error < 0)
596 		goto error_free_irqs;
597 
598 	return 0;
599 
600 error_free_irqs:
601 	fsl_mc_free_irqs(mc_dev);
602 	return error;
603 }
604 
605 /**
606  * dprc_setup - opens and creates a mc_io for DPRC
607  *
608  * @mc_dev: Pointer to fsl-mc device representing a DPRC
609  *
610  * It opens the physical DPRC in the MC.
611  * It configures the DPRC portal used to communicate with MC
612  */
613 
dprc_setup(struct fsl_mc_device * mc_dev)614 int dprc_setup(struct fsl_mc_device *mc_dev)
615 {
616 	struct device *parent_dev = mc_dev->dev.parent;
617 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
618 	struct irq_domain *mc_msi_domain;
619 	bool mc_io_created = false;
620 	bool msi_domain_set = false;
621 	bool uapi_created = false;
622 	u16 major_ver, minor_ver;
623 	size_t region_size;
624 	int error;
625 
626 	if (!is_fsl_mc_bus_dprc(mc_dev))
627 		return -EINVAL;
628 
629 	if (dev_get_msi_domain(&mc_dev->dev))
630 		return -EINVAL;
631 
632 	if (!mc_dev->mc_io) {
633 		/*
634 		 * This is a child DPRC:
635 		 */
636 		if (!dev_is_fsl_mc(parent_dev))
637 			return -EINVAL;
638 
639 		if (mc_dev->obj_desc.region_count == 0)
640 			return -EINVAL;
641 
642 		region_size = resource_size(mc_dev->regions);
643 
644 		error = fsl_create_mc_io(&mc_dev->dev,
645 					 mc_dev->regions[0].start,
646 					 region_size,
647 					 NULL,
648 					 FSL_MC_IO_ATOMIC_CONTEXT_PORTAL,
649 					 &mc_dev->mc_io);
650 		if (error < 0)
651 			return error;
652 
653 		mc_io_created = true;
654 	} else {
655 		error = fsl_mc_uapi_create_device_file(mc_bus);
656 		if (error < 0)
657 			return -EPROBE_DEFER;
658 		uapi_created = true;
659 	}
660 
661 	mc_msi_domain = fsl_mc_find_msi_domain(&mc_dev->dev);
662 	if (!mc_msi_domain) {
663 		dev_warn(&mc_dev->dev,
664 			 "WARNING: MC bus without interrupt support\n");
665 	} else {
666 		dev_set_msi_domain(&mc_dev->dev, mc_msi_domain);
667 		msi_domain_set = true;
668 	}
669 
670 	error = dprc_open(mc_dev->mc_io, 0, mc_dev->obj_desc.id,
671 			  &mc_dev->mc_handle);
672 	if (error < 0) {
673 		dev_err(&mc_dev->dev, "dprc_open() failed: %d\n", error);
674 		goto error_cleanup_msi_domain;
675 	}
676 
677 	error = dprc_get_attributes(mc_dev->mc_io, 0, mc_dev->mc_handle,
678 				    &mc_bus->dprc_attr);
679 	if (error < 0) {
680 		dev_err(&mc_dev->dev, "dprc_get_attributes() failed: %d\n",
681 			error);
682 		goto error_cleanup_open;
683 	}
684 
685 	error = dprc_get_api_version(mc_dev->mc_io, 0,
686 				     &major_ver,
687 				     &minor_ver);
688 	if (error < 0) {
689 		dev_err(&mc_dev->dev, "dprc_get_api_version() failed: %d\n",
690 			error);
691 		goto error_cleanup_open;
692 	}
693 
694 	if (major_ver < DPRC_MIN_VER_MAJOR) {
695 		dev_err(&mc_dev->dev,
696 			"ERROR: DPRC version %d.%d not supported\n",
697 			major_ver, minor_ver);
698 		error = -ENOTSUPP;
699 		goto error_cleanup_open;
700 	}
701 
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 	if (uapi_created)
717 		fsl_mc_uapi_remove_device_file(mc_bus);
718 
719 	return error;
720 }
721 EXPORT_SYMBOL_GPL(dprc_setup);
722 
723 /**
724  * dprc_probe - callback invoked when a DPRC is being bound to this driver
725  *
726  * @mc_dev: Pointer to fsl-mc device representing a DPRC
727  *
728  * It opens the physical DPRC in the MC.
729  * It scans the DPRC to discover the MC objects contained in it.
730  * It creates the interrupt pool for the MC bus associated with the DPRC.
731  * It configures the interrupts for the DPRC device itself.
732  */
dprc_probe(struct fsl_mc_device * mc_dev)733 static int dprc_probe(struct fsl_mc_device *mc_dev)
734 {
735 	int error;
736 
737 	error = dprc_setup(mc_dev);
738 	if (error < 0)
739 		return error;
740 
741 	/*
742 	 * Discover MC objects in DPRC object:
743 	 */
744 	error = dprc_scan_container(mc_dev, true);
745 	if (error < 0)
746 		goto dprc_cleanup;
747 
748 	/*
749 	 * Configure interrupt for the DPRC object associated with this MC bus:
750 	 */
751 	error = dprc_setup_irq(mc_dev);
752 	if (error < 0)
753 		goto scan_cleanup;
754 
755 	dev_info(&mc_dev->dev, "DPRC device bound to driver");
756 	return 0;
757 
758 scan_cleanup:
759 	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
760 dprc_cleanup:
761 	dprc_cleanup(mc_dev);
762 	return error;
763 }
764 
765 /*
766  * Tear down interrupt for a given DPRC object
767  */
dprc_teardown_irq(struct fsl_mc_device * mc_dev)768 static void dprc_teardown_irq(struct fsl_mc_device *mc_dev)
769 {
770 	struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
771 
772 	(void)disable_dprc_irq(mc_dev);
773 
774 	devm_free_irq(&mc_dev->dev, irq->msi_desc->irq, &mc_dev->dev);
775 
776 	fsl_mc_free_irqs(mc_dev);
777 }
778 
779 /**
780  * dprc_cleanup - function that cleanups a DPRC
781  *
782  * @mc_dev: Pointer to fsl-mc device representing the DPRC
783  *
784  * It closes the DPRC device in the MC.
785  * It destroys the interrupt pool associated with this MC bus.
786  */
787 
dprc_cleanup(struct fsl_mc_device * mc_dev)788 int dprc_cleanup(struct fsl_mc_device *mc_dev)
789 {
790 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
791 	int error;
792 
793 	/* this function should be called only for DPRCs, it
794 	 * is an error to call it for regular objects
795 	 */
796 	if (!is_fsl_mc_bus_dprc(mc_dev))
797 		return -EINVAL;
798 
799 	if (dev_get_msi_domain(&mc_dev->dev)) {
800 		fsl_mc_cleanup_irq_pool(mc_dev);
801 		dev_set_msi_domain(&mc_dev->dev, NULL);
802 	}
803 
804 	fsl_mc_cleanup_all_resource_pools(mc_dev);
805 
806 	/* if this step fails we cannot go further with cleanup as there is no way of
807 	 * communicating with the firmware
808 	 */
809 	if (!mc_dev->mc_io) {
810 		dev_err(&mc_dev->dev, "mc_io is NULL, tear down cannot be performed in firmware\n");
811 		return -EINVAL;
812 	}
813 
814 	error = dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
815 	if (error < 0)
816 		dev_err(&mc_dev->dev, "dprc_close() failed: %d\n", error);
817 
818 	if (!fsl_mc_is_root_dprc(&mc_dev->dev)) {
819 		fsl_destroy_mc_io(mc_dev->mc_io);
820 		mc_dev->mc_io = NULL;
821 	} else {
822 		fsl_mc_uapi_remove_device_file(mc_bus);
823 	}
824 
825 	return 0;
826 }
827 EXPORT_SYMBOL_GPL(dprc_cleanup);
828 
829 /**
830  * dprc_remove - callback invoked when a DPRC is being unbound from this driver
831  *
832  * @mc_dev: Pointer to fsl-mc device representing the DPRC
833  *
834  * It removes the DPRC's child objects from Linux (not from the MC) and
835  * closes the DPRC device in the MC.
836  * It tears down the interrupts that were configured for the DPRC device.
837  * It destroys the interrupt pool associated with this MC bus.
838  */
dprc_remove(struct fsl_mc_device * mc_dev)839 static int dprc_remove(struct fsl_mc_device *mc_dev)
840 {
841 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
842 
843 	if (!is_fsl_mc_bus_dprc(mc_dev))
844 		return -EINVAL;
845 
846 	if (!mc_bus->irq_resources)
847 		return -EINVAL;
848 
849 	if (dev_get_msi_domain(&mc_dev->dev))
850 		dprc_teardown_irq(mc_dev);
851 
852 	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
853 
854 	dprc_cleanup(mc_dev);
855 
856 	dev_info(&mc_dev->dev, "DPRC device unbound from driver");
857 	return 0;
858 }
859 
860 static const struct fsl_mc_device_id match_id_table[] = {
861 	{
862 	 .vendor = FSL_MC_VENDOR_FREESCALE,
863 	 .obj_type = "dprc"},
864 	{.vendor = 0x0},
865 };
866 
867 static struct fsl_mc_driver dprc_driver = {
868 	.driver = {
869 		   .name = FSL_MC_DPRC_DRIVER_NAME,
870 		   .owner = THIS_MODULE,
871 		   .pm = NULL,
872 		   },
873 	.match_id_table = match_id_table,
874 	.probe = dprc_probe,
875 	.remove = dprc_remove,
876 };
877 
dprc_driver_init(void)878 int __init dprc_driver_init(void)
879 {
880 	return fsl_mc_driver_register(&dprc_driver);
881 }
882 
dprc_driver_exit(void)883 void dprc_driver_exit(void)
884 {
885 	fsl_mc_driver_unregister(&dprc_driver);
886 }
887