1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) STMicroelectronics 2018 - All Rights Reserved
4  * Authors: Ludovic Barre <ludovic.barre@st.com> for STMicroelectronics.
5  *          Fabien Dessenne <fabien.dessenne@st.com> for STMicroelectronics.
6  */
7 
8 #include <linux/arm-smccc.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/interrupt.h>
11 #include <linux/io.h>
12 #include <linux/mailbox_client.h>
13 #include <linux/mfd/syscon.h>
14 #include <linux/module.h>
15 #include <linux/of_address.h>
16 #include <linux/of_device.h>
17 #include <linux/of_reserved_mem.h>
18 #include <linux/pm_wakeirq.h>
19 #include <linux/regmap.h>
20 #include <linux/remoteproc.h>
21 #include <linux/reset.h>
22 #include <linux/slab.h>
23 #include <linux/workqueue.h>
24 
25 #include "remoteproc_internal.h"
26 
27 #define HOLD_BOOT		0
28 #define RELEASE_BOOT		1
29 
30 #define MBOX_NB_VQ		2
31 #define MBOX_NB_MBX		4
32 
33 #define STM32_SMC_RCC		0x82001000
34 #define STM32_SMC_REG_WRITE	0x1
35 
36 #define STM32_MBX_VQ0		"vq0"
37 #define STM32_MBX_VQ0_ID	0
38 #define STM32_MBX_VQ1		"vq1"
39 #define STM32_MBX_VQ1_ID	1
40 #define STM32_MBX_SHUTDOWN	"shutdown"
41 #define STM32_MBX_DETACH	"detach"
42 
43 #define RSC_TBL_SIZE		1024
44 
45 #define M4_STATE_OFF		0
46 #define M4_STATE_INI		1
47 #define M4_STATE_CRUN		2
48 #define M4_STATE_CSTOP		3
49 #define M4_STATE_STANDBY	4
50 #define M4_STATE_CRASH		5
51 
52 struct stm32_syscon {
53 	struct regmap *map;
54 	u32 reg;
55 	u32 mask;
56 };
57 
58 struct stm32_rproc_mem {
59 	char name[20];
60 	void __iomem *cpu_addr;
61 	phys_addr_t bus_addr;
62 	u32 dev_addr;
63 	size_t size;
64 };
65 
66 struct stm32_rproc_mem_ranges {
67 	u32 dev_addr;
68 	u32 bus_addr;
69 	u32 size;
70 };
71 
72 struct stm32_mbox {
73 	const unsigned char name[10];
74 	struct mbox_chan *chan;
75 	struct mbox_client client;
76 	struct work_struct vq_work;
77 	int vq_id;
78 };
79 
80 struct stm32_rproc {
81 	struct reset_control *rst;
82 	struct stm32_syscon hold_boot;
83 	struct stm32_syscon pdds;
84 	struct stm32_syscon m4_state;
85 	struct stm32_syscon rsctbl;
86 	int wdg_irq;
87 	u32 nb_rmems;
88 	struct stm32_rproc_mem *rmems;
89 	struct stm32_mbox mb[MBOX_NB_MBX];
90 	struct workqueue_struct *workqueue;
91 	bool secured_soc;
92 	void __iomem *rsc_va;
93 };
94 
95 static int stm32_rproc_pa_to_da(struct rproc *rproc, phys_addr_t pa, u64 *da)
96 {
97 	unsigned int i;
98 	struct stm32_rproc *ddata = rproc->priv;
99 	struct stm32_rproc_mem *p_mem;
100 
101 	for (i = 0; i < ddata->nb_rmems; i++) {
102 		p_mem = &ddata->rmems[i];
103 
104 		if (pa < p_mem->bus_addr ||
105 		    pa >= p_mem->bus_addr + p_mem->size)
106 			continue;
107 		*da = pa - p_mem->bus_addr + p_mem->dev_addr;
108 		dev_dbg(rproc->dev.parent, "pa %pa to da %llx\n", &pa, *da);
109 		return 0;
110 	}
111 
112 	return -EINVAL;
113 }
114 
115 static int stm32_rproc_mem_alloc(struct rproc *rproc,
116 				 struct rproc_mem_entry *mem)
117 {
118 	struct device *dev = rproc->dev.parent;
119 	void *va;
120 
121 	dev_dbg(dev, "map memory: %pa+%x\n", &mem->dma, mem->len);
122 	va = ioremap_wc(mem->dma, mem->len);
123 	if (IS_ERR_OR_NULL(va)) {
124 		dev_err(dev, "Unable to map memory region: %pa+%x\n",
125 			&mem->dma, mem->len);
126 		return -ENOMEM;
127 	}
128 
129 	/* Update memory entry va */
130 	mem->va = va;
131 
132 	return 0;
133 }
134 
135 static int stm32_rproc_mem_release(struct rproc *rproc,
136 				   struct rproc_mem_entry *mem)
137 {
138 	dev_dbg(rproc->dev.parent, "unmap memory: %pa\n", &mem->dma);
139 	iounmap(mem->va);
140 
141 	return 0;
142 }
143 
144 static int stm32_rproc_of_memory_translations(struct platform_device *pdev,
145 					      struct stm32_rproc *ddata)
146 {
147 	struct device *parent, *dev = &pdev->dev;
148 	struct device_node *np;
149 	struct stm32_rproc_mem *p_mems;
150 	struct stm32_rproc_mem_ranges *mem_range;
151 	int cnt, array_size, i, ret = 0;
152 
153 	parent = dev->parent;
154 	np = parent->of_node;
155 
156 	cnt = of_property_count_elems_of_size(np, "dma-ranges",
157 					      sizeof(*mem_range));
158 	if (cnt <= 0) {
159 		dev_err(dev, "%s: dma-ranges property not defined\n", __func__);
160 		return -EINVAL;
161 	}
162 
163 	p_mems = devm_kcalloc(dev, cnt, sizeof(*p_mems), GFP_KERNEL);
164 	if (!p_mems)
165 		return -ENOMEM;
166 	mem_range = kcalloc(cnt, sizeof(*mem_range), GFP_KERNEL);
167 	if (!mem_range)
168 		return -ENOMEM;
169 
170 	array_size = cnt * sizeof(struct stm32_rproc_mem_ranges) / sizeof(u32);
171 
172 	ret = of_property_read_u32_array(np, "dma-ranges",
173 					 (u32 *)mem_range, array_size);
174 	if (ret) {
175 		dev_err(dev, "error while get dma-ranges property: %x\n", ret);
176 		goto free_mem;
177 	}
178 
179 	for (i = 0; i < cnt; i++) {
180 		p_mems[i].bus_addr = mem_range[i].bus_addr;
181 		p_mems[i].dev_addr = mem_range[i].dev_addr;
182 		p_mems[i].size     = mem_range[i].size;
183 
184 		dev_dbg(dev, "memory range[%i]: da %#x, pa %pa, size %#zx:\n",
185 			i, p_mems[i].dev_addr, &p_mems[i].bus_addr,
186 			p_mems[i].size);
187 	}
188 
189 	ddata->rmems = p_mems;
190 	ddata->nb_rmems = cnt;
191 
192 free_mem:
193 	kfree(mem_range);
194 	return ret;
195 }
196 
197 static int stm32_rproc_mbox_idx(struct rproc *rproc, const unsigned char *name)
198 {
199 	struct stm32_rproc *ddata = rproc->priv;
200 	int i;
201 
202 	for (i = 0; i < ARRAY_SIZE(ddata->mb); i++) {
203 		if (!strncmp(ddata->mb[i].name, name, strlen(name)))
204 			return i;
205 	}
206 	dev_err(&rproc->dev, "mailbox %s not found\n", name);
207 
208 	return -EINVAL;
209 }
210 
211 static int stm32_rproc_prepare(struct rproc *rproc)
212 {
213 	struct device *dev = rproc->dev.parent;
214 	struct device_node *np = dev->of_node;
215 	struct of_phandle_iterator it;
216 	struct rproc_mem_entry *mem;
217 	struct reserved_mem *rmem;
218 	u64 da;
219 	int index = 0;
220 
221 	/* Register associated reserved memory regions */
222 	of_phandle_iterator_init(&it, np, "memory-region", NULL, 0);
223 	while (of_phandle_iterator_next(&it) == 0) {
224 		rmem = of_reserved_mem_lookup(it.node);
225 		if (!rmem) {
226 			of_node_put(it.node);
227 			dev_err(dev, "unable to acquire memory-region\n");
228 			return -EINVAL;
229 		}
230 
231 		if (stm32_rproc_pa_to_da(rproc, rmem->base, &da) < 0) {
232 			of_node_put(it.node);
233 			dev_err(dev, "memory region not valid %pa\n",
234 				&rmem->base);
235 			return -EINVAL;
236 		}
237 
238 		/*  No need to map vdev buffer */
239 		if (strcmp(it.node->name, "vdev0buffer")) {
240 			/* Register memory region */
241 			mem = rproc_mem_entry_init(dev, NULL,
242 						   (dma_addr_t)rmem->base,
243 						   rmem->size, da,
244 						   stm32_rproc_mem_alloc,
245 						   stm32_rproc_mem_release,
246 						   it.node->name);
247 
248 			if (mem)
249 				rproc_coredump_add_segment(rproc, da,
250 							   rmem->size);
251 		} else {
252 			/* Register reserved memory for vdev buffer alloc */
253 			mem = rproc_of_resm_mem_entry_init(dev, index,
254 							   rmem->size,
255 							   rmem->base,
256 							   it.node->name);
257 		}
258 
259 		if (!mem) {
260 			of_node_put(it.node);
261 			return -ENOMEM;
262 		}
263 
264 		rproc_add_carveout(rproc, mem);
265 		index++;
266 	}
267 
268 	return 0;
269 }
270 
271 static int stm32_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw)
272 {
273 	if (rproc_elf_load_rsc_table(rproc, fw))
274 		dev_warn(&rproc->dev, "no resource table found for this firmware\n");
275 
276 	return 0;
277 }
278 
279 static irqreturn_t stm32_rproc_wdg(int irq, void *data)
280 {
281 	struct platform_device *pdev = data;
282 	struct rproc *rproc = platform_get_drvdata(pdev);
283 
284 	rproc_report_crash(rproc, RPROC_WATCHDOG);
285 
286 	return IRQ_HANDLED;
287 }
288 
289 static void stm32_rproc_mb_vq_work(struct work_struct *work)
290 {
291 	struct stm32_mbox *mb = container_of(work, struct stm32_mbox, vq_work);
292 	struct rproc *rproc = dev_get_drvdata(mb->client.dev);
293 
294 	mutex_lock(&rproc->lock);
295 
296 	if (rproc->state != RPROC_RUNNING)
297 		goto unlock_mutex;
298 
299 	if (rproc_vq_interrupt(rproc, mb->vq_id) == IRQ_NONE)
300 		dev_dbg(&rproc->dev, "no message found in vq%d\n", mb->vq_id);
301 
302 unlock_mutex:
303 	mutex_unlock(&rproc->lock);
304 }
305 
306 static void stm32_rproc_mb_callback(struct mbox_client *cl, void *data)
307 {
308 	struct rproc *rproc = dev_get_drvdata(cl->dev);
309 	struct stm32_mbox *mb = container_of(cl, struct stm32_mbox, client);
310 	struct stm32_rproc *ddata = rproc->priv;
311 
312 	queue_work(ddata->workqueue, &mb->vq_work);
313 }
314 
315 static void stm32_rproc_free_mbox(struct rproc *rproc)
316 {
317 	struct stm32_rproc *ddata = rproc->priv;
318 	unsigned int i;
319 
320 	for (i = 0; i < ARRAY_SIZE(ddata->mb); i++) {
321 		if (ddata->mb[i].chan)
322 			mbox_free_channel(ddata->mb[i].chan);
323 		ddata->mb[i].chan = NULL;
324 	}
325 }
326 
327 static const struct stm32_mbox stm32_rproc_mbox[MBOX_NB_MBX] = {
328 	{
329 		.name = STM32_MBX_VQ0,
330 		.vq_id = STM32_MBX_VQ0_ID,
331 		.client = {
332 			.rx_callback = stm32_rproc_mb_callback,
333 			.tx_block = false,
334 		},
335 	},
336 	{
337 		.name = STM32_MBX_VQ1,
338 		.vq_id = STM32_MBX_VQ1_ID,
339 		.client = {
340 			.rx_callback = stm32_rproc_mb_callback,
341 			.tx_block = false,
342 		},
343 	},
344 	{
345 		.name = STM32_MBX_SHUTDOWN,
346 		.vq_id = -1,
347 		.client = {
348 			.tx_block = true,
349 			.tx_done = NULL,
350 			.tx_tout = 500, /* 500 ms time out */
351 		},
352 	},
353 	{
354 		.name = STM32_MBX_DETACH,
355 		.vq_id = -1,
356 		.client = {
357 			.tx_block = true,
358 			.tx_done = NULL,
359 			.tx_tout = 200, /* 200 ms time out to detach should be fair enough */
360 		},
361 	}
362 };
363 
364 static int stm32_rproc_request_mbox(struct rproc *rproc)
365 {
366 	struct stm32_rproc *ddata = rproc->priv;
367 	struct device *dev = &rproc->dev;
368 	unsigned int i;
369 	int j;
370 	const unsigned char *name;
371 	struct mbox_client *cl;
372 
373 	/* Initialise mailbox structure table */
374 	memcpy(ddata->mb, stm32_rproc_mbox, sizeof(stm32_rproc_mbox));
375 
376 	for (i = 0; i < MBOX_NB_MBX; i++) {
377 		name = ddata->mb[i].name;
378 
379 		cl = &ddata->mb[i].client;
380 		cl->dev = dev->parent;
381 
382 		ddata->mb[i].chan = mbox_request_channel_byname(cl, name);
383 		if (IS_ERR(ddata->mb[i].chan)) {
384 			if (PTR_ERR(ddata->mb[i].chan) == -EPROBE_DEFER) {
385 				dev_err_probe(dev->parent,
386 					      PTR_ERR(ddata->mb[i].chan),
387 					      "failed to request mailbox %s\n",
388 					      name);
389 				goto err_probe;
390 			}
391 			dev_warn(dev, "cannot get %s mbox\n", name);
392 			ddata->mb[i].chan = NULL;
393 		}
394 		if (ddata->mb[i].vq_id >= 0) {
395 			INIT_WORK(&ddata->mb[i].vq_work,
396 				  stm32_rproc_mb_vq_work);
397 		}
398 	}
399 
400 	return 0;
401 
402 err_probe:
403 	for (j = i - 1; j >= 0; j--)
404 		if (ddata->mb[j].chan)
405 			mbox_free_channel(ddata->mb[j].chan);
406 	return -EPROBE_DEFER;
407 }
408 
409 static int stm32_rproc_set_hold_boot(struct rproc *rproc, bool hold)
410 {
411 	struct stm32_rproc *ddata = rproc->priv;
412 	struct stm32_syscon hold_boot = ddata->hold_boot;
413 	struct arm_smccc_res smc_res;
414 	int val, err;
415 
416 	val = hold ? HOLD_BOOT : RELEASE_BOOT;
417 
418 	if (IS_ENABLED(CONFIG_HAVE_ARM_SMCCC) && ddata->secured_soc) {
419 		arm_smccc_smc(STM32_SMC_RCC, STM32_SMC_REG_WRITE,
420 			      hold_boot.reg, val, 0, 0, 0, 0, &smc_res);
421 		err = smc_res.a0;
422 	} else {
423 		err = regmap_update_bits(hold_boot.map, hold_boot.reg,
424 					 hold_boot.mask, val);
425 	}
426 
427 	if (err)
428 		dev_err(&rproc->dev, "failed to set hold boot\n");
429 
430 	return err;
431 }
432 
433 static void stm32_rproc_add_coredump_trace(struct rproc *rproc)
434 {
435 	struct rproc_debug_trace *trace;
436 	struct rproc_dump_segment *segment;
437 	bool already_added;
438 
439 	list_for_each_entry(trace, &rproc->traces, node) {
440 		already_added = false;
441 
442 		list_for_each_entry(segment, &rproc->dump_segments, node) {
443 			if (segment->da == trace->trace_mem.da) {
444 				already_added = true;
445 				break;
446 			}
447 		}
448 
449 		if (!already_added)
450 			rproc_coredump_add_segment(rproc, trace->trace_mem.da,
451 						   trace->trace_mem.len);
452 	}
453 }
454 
455 static int stm32_rproc_start(struct rproc *rproc)
456 {
457 	struct stm32_rproc *ddata = rproc->priv;
458 	int err;
459 
460 	stm32_rproc_add_coredump_trace(rproc);
461 
462 	/* clear remote proc Deep Sleep */
463 	if (ddata->pdds.map) {
464 		err = regmap_update_bits(ddata->pdds.map, ddata->pdds.reg,
465 					 ddata->pdds.mask, 0);
466 		if (err) {
467 			dev_err(&rproc->dev, "failed to clear pdds\n");
468 			return err;
469 		}
470 	}
471 
472 	err = stm32_rproc_set_hold_boot(rproc, false);
473 	if (err)
474 		return err;
475 
476 	return stm32_rproc_set_hold_boot(rproc, true);
477 }
478 
479 static int stm32_rproc_attach(struct rproc *rproc)
480 {
481 	stm32_rproc_add_coredump_trace(rproc);
482 
483 	return stm32_rproc_set_hold_boot(rproc, true);
484 }
485 
486 static int stm32_rproc_detach(struct rproc *rproc)
487 {
488 	struct stm32_rproc *ddata = rproc->priv;
489 	int err, idx;
490 
491 	/* Inform the remote processor of the detach */
492 	idx = stm32_rproc_mbox_idx(rproc, STM32_MBX_DETACH);
493 	if (idx >= 0 && ddata->mb[idx].chan) {
494 		err = mbox_send_message(ddata->mb[idx].chan, "stop");
495 		if (err < 0)
496 			dev_warn(&rproc->dev, "warning: remote FW detach without ack\n");
497 	}
498 
499 	/* Allow remote processor to auto-reboot */
500 	return stm32_rproc_set_hold_boot(rproc, false);
501 }
502 
503 static int stm32_rproc_stop(struct rproc *rproc)
504 {
505 	struct stm32_rproc *ddata = rproc->priv;
506 	int err, idx;
507 
508 	/* request shutdown of the remote processor */
509 	if (rproc->state != RPROC_OFFLINE && rproc->state != RPROC_CRASHED) {
510 		idx = stm32_rproc_mbox_idx(rproc, STM32_MBX_SHUTDOWN);
511 		if (idx >= 0 && ddata->mb[idx].chan) {
512 			err = mbox_send_message(ddata->mb[idx].chan, "detach");
513 			if (err < 0)
514 				dev_warn(&rproc->dev, "warning: remote FW shutdown without ack\n");
515 		}
516 	}
517 
518 	err = stm32_rproc_set_hold_boot(rproc, true);
519 	if (err)
520 		return err;
521 
522 	err = reset_control_assert(ddata->rst);
523 	if (err) {
524 		dev_err(&rproc->dev, "failed to assert the reset\n");
525 		return err;
526 	}
527 
528 	/* to allow platform Standby power mode, set remote proc Deep Sleep */
529 	if (ddata->pdds.map) {
530 		err = regmap_update_bits(ddata->pdds.map, ddata->pdds.reg,
531 					 ddata->pdds.mask, 1);
532 		if (err) {
533 			dev_err(&rproc->dev, "failed to set pdds\n");
534 			return err;
535 		}
536 	}
537 
538 	/* update coprocessor state to OFF if available */
539 	if (ddata->m4_state.map) {
540 		err = regmap_update_bits(ddata->m4_state.map,
541 					 ddata->m4_state.reg,
542 					 ddata->m4_state.mask,
543 					 M4_STATE_OFF);
544 		if (err) {
545 			dev_err(&rproc->dev, "failed to set copro state\n");
546 			return err;
547 		}
548 	}
549 
550 	return 0;
551 }
552 
553 static void stm32_rproc_kick(struct rproc *rproc, int vqid)
554 {
555 	struct stm32_rproc *ddata = rproc->priv;
556 	unsigned int i;
557 	int err;
558 
559 	if (WARN_ON(vqid >= MBOX_NB_VQ))
560 		return;
561 
562 	for (i = 0; i < MBOX_NB_MBX; i++) {
563 		if (vqid != ddata->mb[i].vq_id)
564 			continue;
565 		if (!ddata->mb[i].chan)
566 			return;
567 		err = mbox_send_message(ddata->mb[i].chan, "kick");
568 		if (err < 0)
569 			dev_err(&rproc->dev, "%s: failed (%s, err:%d)\n",
570 				__func__, ddata->mb[i].name, err);
571 		return;
572 	}
573 }
574 
575 static int stm32_rproc_da_to_pa(struct rproc *rproc,
576 				u64 da, phys_addr_t *pa)
577 {
578 	struct stm32_rproc *ddata = rproc->priv;
579 	struct device *dev = rproc->dev.parent;
580 	struct stm32_rproc_mem *p_mem;
581 	unsigned int i;
582 
583 	for (i = 0; i < ddata->nb_rmems; i++) {
584 		p_mem = &ddata->rmems[i];
585 
586 		if (da < p_mem->dev_addr ||
587 		    da >= p_mem->dev_addr + p_mem->size)
588 			continue;
589 
590 		*pa = da - p_mem->dev_addr + p_mem->bus_addr;
591 		dev_dbg(dev, "da %llx to pa %pap\n", da, pa);
592 
593 		return 0;
594 	}
595 
596 	dev_err(dev, "can't translate da %llx\n", da);
597 
598 	return -EINVAL;
599 }
600 
601 static struct resource_table *
602 stm32_rproc_get_loaded_rsc_table(struct rproc *rproc, size_t *table_sz)
603 {
604 	struct stm32_rproc *ddata = rproc->priv;
605 	struct device *dev = rproc->dev.parent;
606 	phys_addr_t rsc_pa;
607 	u32 rsc_da;
608 	int err;
609 
610 	/* The resource table has already been mapped, nothing to do */
611 	if (ddata->rsc_va)
612 		goto done;
613 
614 	err = regmap_read(ddata->rsctbl.map, ddata->rsctbl.reg, &rsc_da);
615 	if (err) {
616 		dev_err(dev, "failed to read rsc tbl addr\n");
617 		return ERR_PTR(-EINVAL);
618 	}
619 
620 	if (!rsc_da)
621 		/* no rsc table */
622 		return ERR_PTR(-ENOENT);
623 
624 	err = stm32_rproc_da_to_pa(rproc, rsc_da, &rsc_pa);
625 	if (err)
626 		return ERR_PTR(err);
627 
628 	ddata->rsc_va = devm_ioremap_wc(dev, rsc_pa, RSC_TBL_SIZE);
629 	if (IS_ERR_OR_NULL(ddata->rsc_va)) {
630 		dev_err(dev, "Unable to map memory region: %pa+%zx\n",
631 			&rsc_pa, RSC_TBL_SIZE);
632 		ddata->rsc_va = NULL;
633 		return ERR_PTR(-ENOMEM);
634 	}
635 
636 done:
637 	/*
638 	 * Assuming the resource table fits in 1kB is fair.
639 	 * Notice for the detach, that this 1 kB memory area has to be reserved in the coprocessor
640 	 * firmware for the resource table. On detach, the remoteproc core re-initializes this
641 	 * entire area by overwriting it with the initial values stored in rproc->clean_table.
642 	 */
643 	*table_sz = RSC_TBL_SIZE;
644 	return (struct resource_table *)ddata->rsc_va;
645 }
646 
647 static const struct rproc_ops st_rproc_ops = {
648 	.prepare	= stm32_rproc_prepare,
649 	.start		= stm32_rproc_start,
650 	.stop		= stm32_rproc_stop,
651 	.attach		= stm32_rproc_attach,
652 	.detach		= stm32_rproc_detach,
653 	.kick		= stm32_rproc_kick,
654 	.load		= rproc_elf_load_segments,
655 	.parse_fw	= stm32_rproc_parse_fw,
656 	.find_loaded_rsc_table = rproc_elf_find_loaded_rsc_table,
657 	.get_loaded_rsc_table = stm32_rproc_get_loaded_rsc_table,
658 	.sanity_check	= rproc_elf_sanity_check,
659 	.get_boot_addr	= rproc_elf_get_boot_addr,
660 };
661 
662 static const struct of_device_id stm32_rproc_match[] = {
663 	{ .compatible = "st,stm32mp1-m4" },
664 	{},
665 };
666 MODULE_DEVICE_TABLE(of, stm32_rproc_match);
667 
668 static int stm32_rproc_get_syscon(struct device_node *np, const char *prop,
669 				  struct stm32_syscon *syscon)
670 {
671 	int err = 0;
672 
673 	syscon->map = syscon_regmap_lookup_by_phandle(np, prop);
674 	if (IS_ERR(syscon->map)) {
675 		err = PTR_ERR(syscon->map);
676 		syscon->map = NULL;
677 		goto out;
678 	}
679 
680 	err = of_property_read_u32_index(np, prop, 1, &syscon->reg);
681 	if (err)
682 		goto out;
683 
684 	err = of_property_read_u32_index(np, prop, 2, &syscon->mask);
685 
686 out:
687 	return err;
688 }
689 
690 static int stm32_rproc_parse_dt(struct platform_device *pdev,
691 				struct stm32_rproc *ddata, bool *auto_boot)
692 {
693 	struct device *dev = &pdev->dev;
694 	struct device_node *np = dev->of_node;
695 	struct stm32_syscon tz;
696 	unsigned int tzen;
697 	int err, irq;
698 
699 	irq = platform_get_irq(pdev, 0);
700 	if (irq == -EPROBE_DEFER)
701 		return dev_err_probe(dev, irq, "failed to get interrupt\n");
702 
703 	if (irq > 0) {
704 		err = devm_request_irq(dev, irq, stm32_rproc_wdg, 0,
705 				       dev_name(dev), pdev);
706 		if (err)
707 			return dev_err_probe(dev, err,
708 					     "failed to request wdg irq\n");
709 
710 		ddata->wdg_irq = irq;
711 
712 		if (of_property_read_bool(np, "wakeup-source")) {
713 			device_init_wakeup(dev, true);
714 			dev_pm_set_wake_irq(dev, irq);
715 		}
716 
717 		dev_info(dev, "wdg irq registered\n");
718 	}
719 
720 	ddata->rst = devm_reset_control_get_by_index(dev, 0);
721 	if (IS_ERR(ddata->rst))
722 		return dev_err_probe(dev, PTR_ERR(ddata->rst),
723 				     "failed to get mcu_reset\n");
724 
725 	/*
726 	 * if platform is secured the hold boot bit must be written by
727 	 * smc call and read normally.
728 	 * if not secure the hold boot bit could be read/write normally
729 	 */
730 	err = stm32_rproc_get_syscon(np, "st,syscfg-tz", &tz);
731 	if (err) {
732 		dev_err(dev, "failed to get tz syscfg\n");
733 		return err;
734 	}
735 
736 	err = regmap_read(tz.map, tz.reg, &tzen);
737 	if (err) {
738 		dev_err(dev, "failed to read tzen\n");
739 		return err;
740 	}
741 	ddata->secured_soc = tzen & tz.mask;
742 
743 	err = stm32_rproc_get_syscon(np, "st,syscfg-holdboot",
744 				     &ddata->hold_boot);
745 	if (err) {
746 		dev_err(dev, "failed to get hold boot\n");
747 		return err;
748 	}
749 
750 	err = stm32_rproc_get_syscon(np, "st,syscfg-pdds", &ddata->pdds);
751 	if (err)
752 		dev_info(dev, "failed to get pdds\n");
753 
754 	*auto_boot = of_property_read_bool(np, "st,auto-boot");
755 
756 	/*
757 	 * See if we can check the M4 status, i.e if it was started
758 	 * from the boot loader or not.
759 	 */
760 	err = stm32_rproc_get_syscon(np, "st,syscfg-m4-state",
761 				     &ddata->m4_state);
762 	if (err) {
763 		/* remember this */
764 		ddata->m4_state.map = NULL;
765 		/* no coprocessor state syscon (optional) */
766 		dev_warn(dev, "m4 state not supported\n");
767 
768 		/* no need to go further */
769 		return 0;
770 	}
771 
772 	/* See if we can get the resource table */
773 	err = stm32_rproc_get_syscon(np, "st,syscfg-rsc-tbl",
774 				     &ddata->rsctbl);
775 	if (err) {
776 		/* no rsc table syscon (optional) */
777 		dev_warn(dev, "rsc tbl syscon not supported\n");
778 	}
779 
780 	return 0;
781 }
782 
783 static int stm32_rproc_get_m4_status(struct stm32_rproc *ddata,
784 				     unsigned int *state)
785 {
786 	/* See stm32_rproc_parse_dt() */
787 	if (!ddata->m4_state.map) {
788 		/*
789 		 * We couldn't get the coprocessor's state, assume
790 		 * it is not running.
791 		 */
792 		*state = M4_STATE_OFF;
793 		return 0;
794 	}
795 
796 	return regmap_read(ddata->m4_state.map, ddata->m4_state.reg, state);
797 }
798 
799 static int stm32_rproc_probe(struct platform_device *pdev)
800 {
801 	struct device *dev = &pdev->dev;
802 	struct stm32_rproc *ddata;
803 	struct device_node *np = dev->of_node;
804 	struct rproc *rproc;
805 	unsigned int state;
806 	int ret;
807 
808 	ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
809 	if (ret)
810 		return ret;
811 
812 	rproc = rproc_alloc(dev, np->name, &st_rproc_ops, NULL, sizeof(*ddata));
813 	if (!rproc)
814 		return -ENOMEM;
815 
816 	ddata = rproc->priv;
817 
818 	rproc_coredump_set_elf_info(rproc, ELFCLASS32, EM_NONE);
819 
820 	ret = stm32_rproc_parse_dt(pdev, ddata, &rproc->auto_boot);
821 	if (ret)
822 		goto free_rproc;
823 
824 	ret = stm32_rproc_of_memory_translations(pdev, ddata);
825 	if (ret)
826 		goto free_rproc;
827 
828 	ret = stm32_rproc_get_m4_status(ddata, &state);
829 	if (ret)
830 		goto free_rproc;
831 
832 	if (state == M4_STATE_CRUN)
833 		rproc->state = RPROC_DETACHED;
834 
835 	rproc->has_iommu = false;
836 	ddata->workqueue = create_workqueue(dev_name(dev));
837 	if (!ddata->workqueue) {
838 		dev_err(dev, "cannot create workqueue\n");
839 		ret = -ENOMEM;
840 		goto free_resources;
841 	}
842 
843 	platform_set_drvdata(pdev, rproc);
844 
845 	ret = stm32_rproc_request_mbox(rproc);
846 	if (ret)
847 		goto free_wkq;
848 
849 	ret = rproc_add(rproc);
850 	if (ret)
851 		goto free_mb;
852 
853 	return 0;
854 
855 free_mb:
856 	stm32_rproc_free_mbox(rproc);
857 free_wkq:
858 	destroy_workqueue(ddata->workqueue);
859 free_resources:
860 	rproc_resource_cleanup(rproc);
861 free_rproc:
862 	if (device_may_wakeup(dev)) {
863 		dev_pm_clear_wake_irq(dev);
864 		device_init_wakeup(dev, false);
865 	}
866 	rproc_free(rproc);
867 	return ret;
868 }
869 
870 static int stm32_rproc_remove(struct platform_device *pdev)
871 {
872 	struct rproc *rproc = platform_get_drvdata(pdev);
873 	struct stm32_rproc *ddata = rproc->priv;
874 	struct device *dev = &pdev->dev;
875 
876 	if (atomic_read(&rproc->power) > 0)
877 		rproc_shutdown(rproc);
878 
879 	rproc_del(rproc);
880 	stm32_rproc_free_mbox(rproc);
881 	destroy_workqueue(ddata->workqueue);
882 
883 	if (device_may_wakeup(dev)) {
884 		dev_pm_clear_wake_irq(dev);
885 		device_init_wakeup(dev, false);
886 	}
887 	rproc_free(rproc);
888 
889 	return 0;
890 }
891 
892 static int __maybe_unused stm32_rproc_suspend(struct device *dev)
893 {
894 	struct rproc *rproc = dev_get_drvdata(dev);
895 	struct stm32_rproc *ddata = rproc->priv;
896 
897 	if (device_may_wakeup(dev))
898 		return enable_irq_wake(ddata->wdg_irq);
899 
900 	return 0;
901 }
902 
903 static int __maybe_unused stm32_rproc_resume(struct device *dev)
904 {
905 	struct rproc *rproc = dev_get_drvdata(dev);
906 	struct stm32_rproc *ddata = rproc->priv;
907 
908 	if (device_may_wakeup(dev))
909 		return disable_irq_wake(ddata->wdg_irq);
910 
911 	return 0;
912 }
913 
914 static SIMPLE_DEV_PM_OPS(stm32_rproc_pm_ops,
915 			 stm32_rproc_suspend, stm32_rproc_resume);
916 
917 static struct platform_driver stm32_rproc_driver = {
918 	.probe = stm32_rproc_probe,
919 	.remove = stm32_rproc_remove,
920 	.driver = {
921 		.name = "stm32-rproc",
922 		.pm = &stm32_rproc_pm_ops,
923 		.of_match_table = of_match_ptr(stm32_rproc_match),
924 	},
925 };
926 module_platform_driver(stm32_rproc_driver);
927 
928 MODULE_DESCRIPTION("STM32 Remote Processor Control Driver");
929 MODULE_AUTHOR("Ludovic Barre <ludovic.barre@st.com>");
930 MODULE_AUTHOR("Fabien Dessenne <fabien.dessenne@st.com>");
931 MODULE_LICENSE("GPL v2");
932 
933