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/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 
fsl_mc_device_match(struct fsl_mc_device * mc_dev,struct fsl_mc_obj_desc * obj_desc)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 
fsl_mc_obj_desc_is_allocatable(struct fsl_mc_obj_desc * obj)32 static bool fsl_mc_obj_desc_is_allocatable(struct fsl_mc_obj_desc *obj)
33 {
34 	if (strcmp(obj->type, "dpmcp") == 0 ||
35 	    strcmp(obj->type, "dpcon") == 0 ||
36 	    strcmp(obj->type, "dpbp") == 0)
37 		return true;
38 	else
39 		return false;
40 }
41 
__fsl_mc_device_remove_if_not_in_mc(struct device * dev,void * data)42 static int __fsl_mc_device_remove_if_not_in_mc(struct device *dev, void *data)
43 {
44 	int i;
45 	struct fsl_mc_child_objs *objs;
46 	struct fsl_mc_device *mc_dev;
47 
48 	mc_dev = to_fsl_mc_device(dev);
49 	objs = data;
50 
51 	for (i = 0; i < objs->child_count; i++) {
52 		struct fsl_mc_obj_desc *obj_desc = &objs->child_array[i];
53 
54 		if (strlen(obj_desc->type) != 0 &&
55 		    fsl_mc_device_match(mc_dev, obj_desc))
56 			break;
57 	}
58 
59 	if (i == objs->child_count)
60 		fsl_mc_device_remove(mc_dev);
61 
62 	return 0;
63 }
64 
__fsl_mc_device_remove(struct device * dev,void * data)65 static int __fsl_mc_device_remove(struct device *dev, void *data)
66 {
67 	fsl_mc_device_remove(to_fsl_mc_device(dev));
68 	return 0;
69 }
70 
71 /**
72  * dprc_remove_devices - Removes devices for objects removed from a DPRC
73  *
74  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
75  * @obj_desc_array: array of object descriptors for child objects currently
76  * present in the DPRC in the MC.
77  * @num_child_objects_in_mc: number of entries in obj_desc_array
78  *
79  * Synchronizes the state of the Linux bus driver with the actual state of
80  * the MC by removing devices that represent MC objects that have
81  * been dynamically removed in the physical DPRC.
82  */
dprc_remove_devices(struct fsl_mc_device * mc_bus_dev,struct fsl_mc_obj_desc * obj_desc_array,int num_child_objects_in_mc)83 void dprc_remove_devices(struct fsl_mc_device *mc_bus_dev,
84 			 struct fsl_mc_obj_desc *obj_desc_array,
85 			 int num_child_objects_in_mc)
86 {
87 	if (num_child_objects_in_mc != 0) {
88 		/*
89 		 * Remove child objects that are in the DPRC in Linux,
90 		 * but not in the MC:
91 		 */
92 		struct fsl_mc_child_objs objs;
93 
94 		objs.child_count = num_child_objects_in_mc;
95 		objs.child_array = obj_desc_array;
96 		device_for_each_child(&mc_bus_dev->dev, &objs,
97 				      __fsl_mc_device_remove_if_not_in_mc);
98 	} else {
99 		/*
100 		 * There are no child objects for this DPRC in the MC.
101 		 * So, remove all the child devices from Linux:
102 		 */
103 		device_for_each_child(&mc_bus_dev->dev, NULL,
104 				      __fsl_mc_device_remove);
105 	}
106 }
107 EXPORT_SYMBOL_GPL(dprc_remove_devices);
108 
__fsl_mc_device_match(struct device * dev,void * data)109 static int __fsl_mc_device_match(struct device *dev, void *data)
110 {
111 	struct fsl_mc_obj_desc *obj_desc = data;
112 	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
113 
114 	return fsl_mc_device_match(mc_dev, obj_desc);
115 }
116 
fsl_mc_device_lookup(struct fsl_mc_obj_desc * obj_desc,struct fsl_mc_device * mc_bus_dev)117 struct fsl_mc_device *fsl_mc_device_lookup(struct fsl_mc_obj_desc *obj_desc,
118 					   struct fsl_mc_device *mc_bus_dev)
119 {
120 	struct device *dev;
121 
122 	dev = device_find_child(&mc_bus_dev->dev, obj_desc,
123 				__fsl_mc_device_match);
124 
125 	return dev ? to_fsl_mc_device(dev) : NULL;
126 }
127 
128 /**
129  * check_plugged_state_change - Check change in an MC object's plugged state
130  *
131  * @mc_dev: pointer to the fsl-mc device for a given MC object
132  * @obj_desc: pointer to the MC object's descriptor in the MC
133  *
134  * If the plugged state has changed from unplugged to plugged, the fsl-mc
135  * device is bound to the corresponding device driver.
136  * If the plugged state has changed from plugged to unplugged, the fsl-mc
137  * device is unbound from the corresponding device driver.
138  */
check_plugged_state_change(struct fsl_mc_device * mc_dev,struct fsl_mc_obj_desc * obj_desc)139 static void check_plugged_state_change(struct fsl_mc_device *mc_dev,
140 				       struct fsl_mc_obj_desc *obj_desc)
141 {
142 	int error;
143 	u32 plugged_flag_at_mc =
144 			obj_desc->state & FSL_MC_OBJ_STATE_PLUGGED;
145 
146 	if (plugged_flag_at_mc !=
147 	    (mc_dev->obj_desc.state & FSL_MC_OBJ_STATE_PLUGGED)) {
148 		if (plugged_flag_at_mc) {
149 			mc_dev->obj_desc.state |= FSL_MC_OBJ_STATE_PLUGGED;
150 			error = device_attach(&mc_dev->dev);
151 			if (error < 0) {
152 				dev_err(&mc_dev->dev,
153 					"device_attach() failed: %d\n",
154 					error);
155 			}
156 		} else {
157 			mc_dev->obj_desc.state &= ~FSL_MC_OBJ_STATE_PLUGGED;
158 			device_release_driver(&mc_dev->dev);
159 		}
160 	}
161 }
162 
fsl_mc_obj_device_add(struct fsl_mc_device * mc_bus_dev,struct fsl_mc_obj_desc * obj_desc)163 static void fsl_mc_obj_device_add(struct fsl_mc_device *mc_bus_dev,
164 				  struct fsl_mc_obj_desc *obj_desc)
165 {
166 	int error;
167 	struct fsl_mc_device *child_dev;
168 
169 	/*
170 	 * Check if device is already known to Linux:
171 	 */
172 	child_dev = fsl_mc_device_lookup(obj_desc, mc_bus_dev);
173 	if (child_dev) {
174 		check_plugged_state_change(child_dev, obj_desc);
175 		put_device(&child_dev->dev);
176 	} else {
177 		error = fsl_mc_device_add(obj_desc, NULL, &mc_bus_dev->dev,
178 					  &child_dev);
179 		if (error < 0)
180 			return;
181 	}
182 }
183 
184 /**
185  * dprc_add_new_devices - Adds devices to the logical bus for a DPRC
186  *
187  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
188  * @obj_desc_array: array of device descriptors for child devices currently
189  * present in the physical DPRC.
190  * @num_child_objects_in_mc: number of entries in obj_desc_array
191  *
192  * Synchronizes the state of the Linux bus driver with the actual
193  * state of the MC by adding objects that have been newly discovered
194  * in the physical DPRC.
195  */
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)196 static void dprc_add_new_devices(struct fsl_mc_device *mc_bus_dev,
197 				 struct fsl_mc_obj_desc *obj_desc_array,
198 				 int num_child_objects_in_mc)
199 {
200 	int i;
201 
202 	/* probe the allocable objects first */
203 	for (i = 0; i < num_child_objects_in_mc; i++) {
204 		struct fsl_mc_obj_desc *obj_desc = &obj_desc_array[i];
205 
206 		if (strlen(obj_desc->type) > 0 &&
207 		    fsl_mc_obj_desc_is_allocatable(obj_desc))
208 			fsl_mc_obj_device_add(mc_bus_dev, obj_desc);
209 	}
210 
211 	for (i = 0; i < num_child_objects_in_mc; i++) {
212 		struct fsl_mc_obj_desc *obj_desc = &obj_desc_array[i];
213 
214 		if (strlen(obj_desc->type) > 0 &&
215 		    !fsl_mc_obj_desc_is_allocatable(obj_desc))
216 			fsl_mc_obj_device_add(mc_bus_dev, obj_desc);
217 	}
218 }
219 
220 /**
221  * dprc_scan_objects - Discover objects in a DPRC
222  *
223  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
224  * @alloc_interrupts: if true the function allocates the interrupt pool,
225  * otherwise the interrupt allocation is delayed
226  *
227  * Detects objects added and removed from a DPRC and synchronizes the
228  * state of the Linux bus driver, MC by adding and removing
229  * devices accordingly.
230  * Two types of devices can be found in a DPRC: allocatable objects (e.g.,
231  * dpbp, dpmcp) and non-allocatable devices (e.g., dprc, dpni).
232  * All allocatable devices needed to be probed before all non-allocatable
233  * devices, to ensure that device drivers for non-allocatable
234  * devices can allocate any type of allocatable devices.
235  * That is, we need to ensure that the corresponding resource pools are
236  * populated before they can get allocation requests from probe callbacks
237  * of the device drivers for the non-allocatable devices.
238  */
dprc_scan_objects(struct fsl_mc_device * mc_bus_dev,bool alloc_interrupts)239 int dprc_scan_objects(struct fsl_mc_device *mc_bus_dev,
240 		      bool alloc_interrupts)
241 {
242 	int num_child_objects;
243 	int dprc_get_obj_failures;
244 	int error;
245 	unsigned int irq_count = mc_bus_dev->obj_desc.irq_count;
246 	struct fsl_mc_obj_desc *child_obj_desc_array = NULL;
247 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
248 
249 	error = dprc_get_obj_count(mc_bus_dev->mc_io,
250 				   0,
251 				   mc_bus_dev->mc_handle,
252 				   &num_child_objects);
253 	if (error < 0) {
254 		dev_err(&mc_bus_dev->dev, "dprc_get_obj_count() failed: %d\n",
255 			error);
256 		return error;
257 	}
258 
259 	if (num_child_objects != 0) {
260 		int i;
261 
262 		child_obj_desc_array =
263 		    devm_kmalloc_array(&mc_bus_dev->dev, num_child_objects,
264 				       sizeof(*child_obj_desc_array),
265 				       GFP_KERNEL);
266 		if (!child_obj_desc_array)
267 			return -ENOMEM;
268 
269 		/*
270 		 * Discover objects currently present in the physical DPRC:
271 		 */
272 		dprc_get_obj_failures = 0;
273 		for (i = 0; i < num_child_objects; i++) {
274 			struct fsl_mc_obj_desc *obj_desc =
275 			    &child_obj_desc_array[i];
276 
277 			error = dprc_get_obj(mc_bus_dev->mc_io,
278 					     0,
279 					     mc_bus_dev->mc_handle,
280 					     i, obj_desc);
281 			if (error < 0) {
282 				dev_err(&mc_bus_dev->dev,
283 					"dprc_get_obj(i=%d) failed: %d\n",
284 					i, error);
285 				/*
286 				 * Mark the obj entry as "invalid", by using the
287 				 * empty string as obj type:
288 				 */
289 				obj_desc->type[0] = '\0';
290 				obj_desc->id = error;
291 				dprc_get_obj_failures++;
292 				continue;
293 			}
294 
295 			/*
296 			 * add a quirk for all versions of dpsec < 4.0...none
297 			 * are coherent regardless of what the MC reports.
298 			 */
299 			if ((strcmp(obj_desc->type, "dpseci") == 0) &&
300 			    (obj_desc->ver_major < 4))
301 				obj_desc->flags |=
302 					FSL_MC_OBJ_FLAG_NO_MEM_SHAREABILITY;
303 
304 			irq_count += obj_desc->irq_count;
305 			dev_dbg(&mc_bus_dev->dev,
306 				"Discovered object: type %s, id %d\n",
307 				obj_desc->type, obj_desc->id);
308 		}
309 
310 		if (dprc_get_obj_failures != 0) {
311 			dev_err(&mc_bus_dev->dev,
312 				"%d out of %d devices could not be retrieved\n",
313 				dprc_get_obj_failures, num_child_objects);
314 		}
315 	}
316 
317 	/*
318 	 * Allocate IRQ's before binding the scanned devices with their
319 	 * respective drivers.
320 	 */
321 	if (dev_get_msi_domain(&mc_bus_dev->dev)) {
322 		if (irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS) {
323 			dev_warn(&mc_bus_dev->dev,
324 				 "IRQs needed (%u) exceed IRQs preallocated (%u)\n",
325 				 irq_count, FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
326 		}
327 
328 		if (alloc_interrupts && !mc_bus->irq_resources) {
329 			error = fsl_mc_populate_irq_pool(mc_bus_dev,
330 					 FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
331 			if (error < 0)
332 				return error;
333 		}
334 	}
335 
336 	dprc_remove_devices(mc_bus_dev, child_obj_desc_array,
337 			    num_child_objects);
338 
339 	dprc_add_new_devices(mc_bus_dev, child_obj_desc_array,
340 			     num_child_objects);
341 
342 	if (child_obj_desc_array)
343 		devm_kfree(&mc_bus_dev->dev, child_obj_desc_array);
344 
345 	return 0;
346 }
347 
348 /**
349  * dprc_scan_container - Scans a physical DPRC and synchronizes Linux bus state
350  *
351  * @mc_bus_dev: pointer to the fsl-mc device that represents a DPRC object
352  * @alloc_interrupts: if true the function allocates the interrupt pool,
353  *                    otherwise the interrupt allocation is delayed
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  */
dprc_scan_container(struct fsl_mc_device * mc_bus_dev,bool alloc_interrupts)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 /**
378  * dprc_irq0_handler - Regular ISR for DPRC interrupt 0
379  *
380  * @irq_num: IRQ number of the interrupt being handled
381  * @arg: Pointer to device structure
382  */
dprc_irq0_handler(int irq_num,void * arg)383 static irqreturn_t dprc_irq0_handler(int irq_num, void *arg)
384 {
385 	return IRQ_WAKE_THREAD;
386 }
387 
388 /**
389  * dprc_irq0_handler_thread - Handler thread function for DPRC interrupt 0
390  *
391  * @irq_num: IRQ number of the interrupt being handled
392  * @arg: Pointer to device structure
393  */
dprc_irq0_handler_thread(int irq_num,void * arg)394 static irqreturn_t dprc_irq0_handler_thread(int irq_num, void *arg)
395 {
396 	int error;
397 	u32 status;
398 	struct device *dev = arg;
399 	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
400 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
401 	struct fsl_mc_io *mc_io = mc_dev->mc_io;
402 	int irq = mc_dev->irqs[0]->virq;
403 
404 	dev_dbg(dev, "DPRC IRQ %d triggered on CPU %u\n",
405 		irq_num, smp_processor_id());
406 
407 	if (!(mc_dev->flags & FSL_MC_IS_DPRC))
408 		return IRQ_HANDLED;
409 
410 	mutex_lock(&mc_bus->scan_mutex);
411 	if (irq != (u32)irq_num)
412 		goto out;
413 
414 	status = 0;
415 	error = dprc_get_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
416 				    &status);
417 	if (error < 0) {
418 		dev_err(dev,
419 			"dprc_get_irq_status() failed: %d\n", error);
420 		goto out;
421 	}
422 
423 	error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0,
424 				      status);
425 	if (error < 0) {
426 		dev_err(dev,
427 			"dprc_clear_irq_status() failed: %d\n", error);
428 		goto out;
429 	}
430 
431 	if (status & (DPRC_IRQ_EVENT_OBJ_ADDED |
432 		      DPRC_IRQ_EVENT_OBJ_REMOVED |
433 		      DPRC_IRQ_EVENT_CONTAINER_DESTROYED |
434 		      DPRC_IRQ_EVENT_OBJ_DESTROYED |
435 		      DPRC_IRQ_EVENT_OBJ_CREATED)) {
436 
437 		error = dprc_scan_objects(mc_dev, true);
438 		if (error < 0) {
439 			/*
440 			 * If the error is -ENXIO, we ignore it, as it indicates
441 			 * that the object scan was aborted, as we detected that
442 			 * an object was removed from the DPRC in the MC, while
443 			 * we were scanning the DPRC.
444 			 */
445 			if (error != -ENXIO) {
446 				dev_err(dev, "dprc_scan_objects() failed: %d\n",
447 					error);
448 			}
449 
450 			goto out;
451 		}
452 	}
453 
454 out:
455 	mutex_unlock(&mc_bus->scan_mutex);
456 	return IRQ_HANDLED;
457 }
458 
459 /*
460  * Disable and clear interrupt for a given DPRC object
461  */
disable_dprc_irq(struct fsl_mc_device * mc_dev)462 int disable_dprc_irq(struct fsl_mc_device *mc_dev)
463 {
464 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
465 	int error;
466 	struct fsl_mc_io *mc_io = mc_dev->mc_io;
467 
468 	/*
469 	 * Disable generation of interrupt, while we configure it:
470 	 */
471 	error = dprc_set_irq_enable(mc_io, 0, mc_dev->mc_handle, 0, 0);
472 	if (error < 0) {
473 		dev_err(&mc_dev->dev,
474 			"Disabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
475 			error);
476 		return error;
477 	}
478 
479 	/*
480 	 * Disable all interrupt causes for the interrupt:
481 	 */
482 	error = dprc_set_irq_mask(mc_io, 0, mc_dev->mc_handle, 0, 0x0);
483 	if (error < 0) {
484 		dev_err(&mc_dev->dev,
485 			"Disabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
486 			error);
487 		return error;
488 	}
489 
490 	/*
491 	 * Clear any leftover interrupts:
492 	 */
493 	error = dprc_clear_irq_status(mc_io, 0, mc_dev->mc_handle, 0, ~0x0U);
494 	if (error < 0) {
495 		dev_err(&mc_dev->dev,
496 			"Disabling DPRC IRQ failed: dprc_clear_irq_status() failed: %d\n",
497 			error);
498 		return error;
499 	}
500 
501 	mc_bus->irq_enabled = 0;
502 
503 	return 0;
504 }
505 
get_dprc_irq_state(struct fsl_mc_device * mc_dev)506 int get_dprc_irq_state(struct fsl_mc_device *mc_dev)
507 {
508 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
509 
510 	return mc_bus->irq_enabled;
511 }
512 
register_dprc_irq_handler(struct fsl_mc_device * mc_dev)513 static int register_dprc_irq_handler(struct fsl_mc_device *mc_dev)
514 {
515 	int error;
516 	struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
517 
518 	/*
519 	 * NOTE: devm_request_threaded_irq() invokes the device-specific
520 	 * function that programs the MSI physically in the device
521 	 */
522 	error = devm_request_threaded_irq(&mc_dev->dev,
523 					  irq->virq,
524 					  dprc_irq0_handler,
525 					  dprc_irq0_handler_thread,
526 					  IRQF_NO_SUSPEND | IRQF_ONESHOT,
527 					  dev_name(&mc_dev->dev),
528 					  &mc_dev->dev);
529 	if (error < 0) {
530 		dev_err(&mc_dev->dev,
531 			"devm_request_threaded_irq() failed: %d\n",
532 			error);
533 		return error;
534 	}
535 
536 	return 0;
537 }
538 
enable_dprc_irq(struct fsl_mc_device * mc_dev)539 int enable_dprc_irq(struct fsl_mc_device *mc_dev)
540 {
541 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
542 	int error;
543 
544 	/*
545 	 * Enable all interrupt causes for the interrupt:
546 	 */
547 	error = dprc_set_irq_mask(mc_dev->mc_io, 0, mc_dev->mc_handle, 0,
548 				  ~0x0u);
549 	if (error < 0) {
550 		dev_err(&mc_dev->dev,
551 			"Enabling DPRC IRQ failed: dprc_set_irq_mask() failed: %d\n",
552 			error);
553 
554 		return error;
555 	}
556 
557 	/*
558 	 * Enable generation of the interrupt:
559 	 */
560 	error = dprc_set_irq_enable(mc_dev->mc_io, 0, mc_dev->mc_handle, 0, 1);
561 	if (error < 0) {
562 		dev_err(&mc_dev->dev,
563 			"Enabling DPRC IRQ failed: dprc_set_irq_enable() failed: %d\n",
564 			error);
565 
566 		return error;
567 	}
568 
569 	mc_bus->irq_enabled = 1;
570 
571 	return 0;
572 }
573 
574 /*
575  * Setup interrupt for a given DPRC device
576  */
dprc_setup_irq(struct fsl_mc_device * mc_dev)577 static int dprc_setup_irq(struct fsl_mc_device *mc_dev)
578 {
579 	int error;
580 
581 	error = fsl_mc_allocate_irqs(mc_dev);
582 	if (error < 0)
583 		return error;
584 
585 	error = disable_dprc_irq(mc_dev);
586 	if (error < 0)
587 		goto error_free_irqs;
588 
589 	error = register_dprc_irq_handler(mc_dev);
590 	if (error < 0)
591 		goto error_free_irqs;
592 
593 	error = enable_dprc_irq(mc_dev);
594 	if (error < 0)
595 		goto error_free_irqs;
596 
597 	return 0;
598 
599 error_free_irqs:
600 	fsl_mc_free_irqs(mc_dev);
601 	return error;
602 }
603 
604 /**
605  * dprc_setup - opens and creates a mc_io for DPRC
606  *
607  * @mc_dev: Pointer to fsl-mc device representing a DPRC
608  *
609  * It opens the physical DPRC in the MC.
610  * It configures the DPRC portal used to communicate with MC
611  */
612 
dprc_setup(struct fsl_mc_device * mc_dev)613 int dprc_setup(struct fsl_mc_device *mc_dev)
614 {
615 	struct device *parent_dev = mc_dev->dev.parent;
616 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
617 	struct irq_domain *mc_msi_domain;
618 	bool mc_io_created = false;
619 	bool msi_domain_set = false;
620 	bool uapi_created = false;
621 	u16 major_ver, minor_ver;
622 	size_t region_size;
623 	int error;
624 
625 	if (!is_fsl_mc_bus_dprc(mc_dev))
626 		return -EINVAL;
627 
628 	if (dev_get_msi_domain(&mc_dev->dev))
629 		return -EINVAL;
630 
631 	if (!mc_dev->mc_io) {
632 		/*
633 		 * This is a child DPRC:
634 		 */
635 		if (!dev_is_fsl_mc(parent_dev))
636 			return -EINVAL;
637 
638 		if (mc_dev->obj_desc.region_count == 0)
639 			return -EINVAL;
640 
641 		region_size = resource_size(mc_dev->regions);
642 
643 		error = fsl_create_mc_io(&mc_dev->dev,
644 					 mc_dev->regions[0].start,
645 					 region_size,
646 					 NULL,
647 					 FSL_MC_IO_ATOMIC_CONTEXT_PORTAL,
648 					 &mc_dev->mc_io);
649 		if (error < 0)
650 			return error;
651 
652 		mc_io_created = true;
653 	} else {
654 		error = fsl_mc_uapi_create_device_file(mc_bus);
655 		if (error < 0)
656 			return -EPROBE_DEFER;
657 		uapi_created = true;
658 	}
659 
660 	mc_msi_domain = fsl_mc_find_msi_domain(&mc_dev->dev);
661 	if (!mc_msi_domain) {
662 		dev_warn(&mc_dev->dev,
663 			 "WARNING: MC bus without interrupt support\n");
664 	} else {
665 		dev_set_msi_domain(&mc_dev->dev, mc_msi_domain);
666 		msi_domain_set = true;
667 	}
668 
669 	error = dprc_open(mc_dev->mc_io, 0, mc_dev->obj_desc.id,
670 			  &mc_dev->mc_handle);
671 	if (error < 0) {
672 		dev_err(&mc_dev->dev, "dprc_open() failed: %d\n", error);
673 		goto error_cleanup_msi_domain;
674 	}
675 
676 	error = dprc_get_attributes(mc_dev->mc_io, 0, mc_dev->mc_handle,
677 				    &mc_bus->dprc_attr);
678 	if (error < 0) {
679 		dev_err(&mc_dev->dev, "dprc_get_attributes() failed: %d\n",
680 			error);
681 		goto error_cleanup_open;
682 	}
683 
684 	error = dprc_get_api_version(mc_dev->mc_io, 0,
685 				     &major_ver,
686 				     &minor_ver);
687 	if (error < 0) {
688 		dev_err(&mc_dev->dev, "dprc_get_api_version() failed: %d\n",
689 			error);
690 		goto error_cleanup_open;
691 	}
692 
693 	if (major_ver < DPRC_MIN_VER_MAJOR) {
694 		dev_err(&mc_dev->dev,
695 			"ERROR: DPRC version %d.%d not supported\n",
696 			major_ver, minor_ver);
697 		error = -ENOTSUPP;
698 		goto error_cleanup_open;
699 	}
700 
701 	return 0;
702 
703 error_cleanup_open:
704 	(void)dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
705 
706 error_cleanup_msi_domain:
707 	if (msi_domain_set)
708 		dev_set_msi_domain(&mc_dev->dev, NULL);
709 
710 	if (mc_io_created) {
711 		fsl_destroy_mc_io(mc_dev->mc_io);
712 		mc_dev->mc_io = NULL;
713 	}
714 
715 	if (uapi_created)
716 		fsl_mc_uapi_remove_device_file(mc_bus);
717 
718 	return error;
719 }
720 EXPORT_SYMBOL_GPL(dprc_setup);
721 
722 /**
723  * dprc_probe - callback invoked when a DPRC is being bound to this driver
724  *
725  * @mc_dev: Pointer to fsl-mc device representing a DPRC
726  *
727  * It opens the physical DPRC in the MC.
728  * It scans the DPRC to discover the MC objects contained in it.
729  * It creates the interrupt pool for the MC bus associated with the DPRC.
730  * It configures the interrupts for the DPRC device itself.
731  */
dprc_probe(struct fsl_mc_device * mc_dev)732 static int dprc_probe(struct fsl_mc_device *mc_dev)
733 {
734 	int error;
735 
736 	error = dprc_setup(mc_dev);
737 	if (error < 0)
738 		return error;
739 
740 	/*
741 	 * Discover MC objects in DPRC object:
742 	 */
743 	error = dprc_scan_container(mc_dev, true);
744 	if (error < 0)
745 		goto dprc_cleanup;
746 
747 	/*
748 	 * Configure interrupt for the DPRC object associated with this MC bus:
749 	 */
750 	error = dprc_setup_irq(mc_dev);
751 	if (error < 0)
752 		goto scan_cleanup;
753 
754 	dev_info(&mc_dev->dev, "DPRC device bound to driver");
755 	return 0;
756 
757 scan_cleanup:
758 	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
759 dprc_cleanup:
760 	dprc_cleanup(mc_dev);
761 	return error;
762 }
763 
764 /*
765  * Tear down interrupt for a given DPRC object
766  */
dprc_teardown_irq(struct fsl_mc_device * mc_dev)767 static void dprc_teardown_irq(struct fsl_mc_device *mc_dev)
768 {
769 	struct fsl_mc_device_irq *irq = mc_dev->irqs[0];
770 
771 	(void)disable_dprc_irq(mc_dev);
772 
773 	devm_free_irq(&mc_dev->dev, irq->virq, &mc_dev->dev);
774 
775 	fsl_mc_free_irqs(mc_dev);
776 }
777 
778 /**
779  * dprc_cleanup - function that cleanups a DPRC
780  *
781  * @mc_dev: Pointer to fsl-mc device representing the DPRC
782  *
783  * It closes the DPRC device in the MC.
784  * It destroys the interrupt pool associated with this MC bus.
785  */
786 
dprc_cleanup(struct fsl_mc_device * mc_dev)787 int dprc_cleanup(struct fsl_mc_device *mc_dev)
788 {
789 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
790 	int error;
791 
792 	/* this function should be called only for DPRCs, it
793 	 * is an error to call it for regular objects
794 	 */
795 	if (!is_fsl_mc_bus_dprc(mc_dev))
796 		return -EINVAL;
797 
798 	if (dev_get_msi_domain(&mc_dev->dev)) {
799 		fsl_mc_cleanup_irq_pool(mc_dev);
800 		dev_set_msi_domain(&mc_dev->dev, NULL);
801 	}
802 
803 	fsl_mc_cleanup_all_resource_pools(mc_dev);
804 
805 	/* if this step fails we cannot go further with cleanup as there is no way of
806 	 * communicating with the firmware
807 	 */
808 	if (!mc_dev->mc_io) {
809 		dev_err(&mc_dev->dev, "mc_io is NULL, tear down cannot be performed in firmware\n");
810 		return -EINVAL;
811 	}
812 
813 	error = dprc_close(mc_dev->mc_io, 0, mc_dev->mc_handle);
814 	if (error < 0)
815 		dev_err(&mc_dev->dev, "dprc_close() failed: %d\n", error);
816 
817 	if (!fsl_mc_is_root_dprc(&mc_dev->dev)) {
818 		fsl_destroy_mc_io(mc_dev->mc_io);
819 		mc_dev->mc_io = NULL;
820 	} else {
821 		fsl_mc_uapi_remove_device_file(mc_bus);
822 	}
823 
824 	return 0;
825 }
826 EXPORT_SYMBOL_GPL(dprc_cleanup);
827 
828 /**
829  * dprc_remove - callback invoked when a DPRC is being unbound from this driver
830  *
831  * @mc_dev: Pointer to fsl-mc device representing the DPRC
832  *
833  * It removes the DPRC's child objects from Linux (not from the MC) and
834  * closes the DPRC device in the MC.
835  * It tears down the interrupts that were configured for the DPRC device.
836  * It destroys the interrupt pool associated with this MC bus.
837  */
dprc_remove(struct fsl_mc_device * mc_dev)838 static int dprc_remove(struct fsl_mc_device *mc_dev)
839 {
840 	struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_dev);
841 
842 	if (!is_fsl_mc_bus_dprc(mc_dev))
843 		return -EINVAL;
844 
845 	if (!mc_bus->irq_resources)
846 		return -EINVAL;
847 
848 	if (dev_get_msi_domain(&mc_dev->dev))
849 		dprc_teardown_irq(mc_dev);
850 
851 	device_for_each_child(&mc_dev->dev, NULL, __fsl_mc_device_remove);
852 
853 	dprc_cleanup(mc_dev);
854 
855 	dev_info(&mc_dev->dev, "DPRC device unbound from driver");
856 	return 0;
857 }
858 
859 static const struct fsl_mc_device_id match_id_table[] = {
860 	{
861 	 .vendor = FSL_MC_VENDOR_FREESCALE,
862 	 .obj_type = "dprc"},
863 	{.vendor = 0x0},
864 };
865 
866 static struct fsl_mc_driver dprc_driver = {
867 	.driver = {
868 		   .name = FSL_MC_DPRC_DRIVER_NAME,
869 		   .owner = THIS_MODULE,
870 		   .pm = NULL,
871 		   },
872 	.match_id_table = match_id_table,
873 	.probe = dprc_probe,
874 	.remove = dprc_remove,
875 };
876 
dprc_driver_init(void)877 int __init dprc_driver_init(void)
878 {
879 	return fsl_mc_driver_register(&dprc_driver);
880 }
881 
dprc_driver_exit(void)882 void dprc_driver_exit(void)
883 {
884 	fsl_mc_driver_unregister(&dprc_driver);
885 }
886