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 			dev_err(dev, "unable to acquire memory-region\n");
227 			return -EINVAL;
228 		}
229 
230 		if (stm32_rproc_pa_to_da(rproc, rmem->base, &da) < 0) {
231 			dev_err(dev, "memory region not valid %pa\n",
232 				&rmem->base);
233 			return -EINVAL;
234 		}
235 
236 		/*  No need to map vdev buffer */
237 		if (strcmp(it.node->name, "vdev0buffer")) {
238 			/* Register memory region */
239 			mem = rproc_mem_entry_init(dev, NULL,
240 						   (dma_addr_t)rmem->base,
241 						   rmem->size, da,
242 						   stm32_rproc_mem_alloc,
243 						   stm32_rproc_mem_release,
244 						   it.node->name);
245 
246 			if (mem)
247 				rproc_coredump_add_segment(rproc, da,
248 							   rmem->size);
249 		} else {
250 			/* Register reserved memory for vdev buffer alloc */
251 			mem = rproc_of_resm_mem_entry_init(dev, index,
252 							   rmem->size,
253 							   rmem->base,
254 							   it.node->name);
255 		}
256 
257 		if (!mem)
258 			return -ENOMEM;
259 
260 		rproc_add_carveout(rproc, mem);
261 		index++;
262 	}
263 
264 	return 0;
265 }
266 
267 static int stm32_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw)
268 {
269 	if (rproc_elf_load_rsc_table(rproc, fw))
270 		dev_warn(&rproc->dev, "no resource table found for this firmware\n");
271 
272 	return 0;
273 }
274 
275 static irqreturn_t stm32_rproc_wdg(int irq, void *data)
276 {
277 	struct platform_device *pdev = data;
278 	struct rproc *rproc = platform_get_drvdata(pdev);
279 
280 	rproc_report_crash(rproc, RPROC_WATCHDOG);
281 
282 	return IRQ_HANDLED;
283 }
284 
285 static void stm32_rproc_mb_vq_work(struct work_struct *work)
286 {
287 	struct stm32_mbox *mb = container_of(work, struct stm32_mbox, vq_work);
288 	struct rproc *rproc = dev_get_drvdata(mb->client.dev);
289 
290 	if (rproc_vq_interrupt(rproc, mb->vq_id) == IRQ_NONE)
291 		dev_dbg(&rproc->dev, "no message found in vq%d\n", mb->vq_id);
292 }
293 
294 static void stm32_rproc_mb_callback(struct mbox_client *cl, void *data)
295 {
296 	struct rproc *rproc = dev_get_drvdata(cl->dev);
297 	struct stm32_mbox *mb = container_of(cl, struct stm32_mbox, client);
298 	struct stm32_rproc *ddata = rproc->priv;
299 
300 	queue_work(ddata->workqueue, &mb->vq_work);
301 }
302 
303 static void stm32_rproc_free_mbox(struct rproc *rproc)
304 {
305 	struct stm32_rproc *ddata = rproc->priv;
306 	unsigned int i;
307 
308 	for (i = 0; i < ARRAY_SIZE(ddata->mb); i++) {
309 		if (ddata->mb[i].chan)
310 			mbox_free_channel(ddata->mb[i].chan);
311 		ddata->mb[i].chan = NULL;
312 	}
313 }
314 
315 static const struct stm32_mbox stm32_rproc_mbox[MBOX_NB_MBX] = {
316 	{
317 		.name = STM32_MBX_VQ0,
318 		.vq_id = STM32_MBX_VQ0_ID,
319 		.client = {
320 			.rx_callback = stm32_rproc_mb_callback,
321 			.tx_block = false,
322 		},
323 	},
324 	{
325 		.name = STM32_MBX_VQ1,
326 		.vq_id = STM32_MBX_VQ1_ID,
327 		.client = {
328 			.rx_callback = stm32_rproc_mb_callback,
329 			.tx_block = false,
330 		},
331 	},
332 	{
333 		.name = STM32_MBX_SHUTDOWN,
334 		.vq_id = -1,
335 		.client = {
336 			.tx_block = true,
337 			.tx_done = NULL,
338 			.tx_tout = 500, /* 500 ms time out */
339 		},
340 	},
341 	{
342 		.name = STM32_MBX_DETACH,
343 		.vq_id = -1,
344 		.client = {
345 			.tx_block = true,
346 			.tx_done = NULL,
347 			.tx_tout = 200, /* 200 ms time out to detach should be fair enough */
348 		},
349 	}
350 };
351 
352 static int stm32_rproc_request_mbox(struct rproc *rproc)
353 {
354 	struct stm32_rproc *ddata = rproc->priv;
355 	struct device *dev = &rproc->dev;
356 	unsigned int i;
357 	int j;
358 	const unsigned char *name;
359 	struct mbox_client *cl;
360 
361 	/* Initialise mailbox structure table */
362 	memcpy(ddata->mb, stm32_rproc_mbox, sizeof(stm32_rproc_mbox));
363 
364 	for (i = 0; i < MBOX_NB_MBX; i++) {
365 		name = ddata->mb[i].name;
366 
367 		cl = &ddata->mb[i].client;
368 		cl->dev = dev->parent;
369 
370 		ddata->mb[i].chan = mbox_request_channel_byname(cl, name);
371 		if (IS_ERR(ddata->mb[i].chan)) {
372 			if (PTR_ERR(ddata->mb[i].chan) == -EPROBE_DEFER) {
373 				dev_err_probe(dev->parent,
374 					      PTR_ERR(ddata->mb[i].chan),
375 					      "failed to request mailbox %s\n",
376 					      name);
377 				goto err_probe;
378 			}
379 			dev_warn(dev, "cannot get %s mbox\n", name);
380 			ddata->mb[i].chan = NULL;
381 		}
382 		if (ddata->mb[i].vq_id >= 0) {
383 			INIT_WORK(&ddata->mb[i].vq_work,
384 				  stm32_rproc_mb_vq_work);
385 		}
386 	}
387 
388 	return 0;
389 
390 err_probe:
391 	for (j = i - 1; j >= 0; j--)
392 		if (ddata->mb[j].chan)
393 			mbox_free_channel(ddata->mb[j].chan);
394 	return -EPROBE_DEFER;
395 }
396 
397 static int stm32_rproc_set_hold_boot(struct rproc *rproc, bool hold)
398 {
399 	struct stm32_rproc *ddata = rproc->priv;
400 	struct stm32_syscon hold_boot = ddata->hold_boot;
401 	struct arm_smccc_res smc_res;
402 	int val, err;
403 
404 	val = hold ? HOLD_BOOT : RELEASE_BOOT;
405 
406 	if (IS_ENABLED(CONFIG_HAVE_ARM_SMCCC) && ddata->secured_soc) {
407 		arm_smccc_smc(STM32_SMC_RCC, STM32_SMC_REG_WRITE,
408 			      hold_boot.reg, val, 0, 0, 0, 0, &smc_res);
409 		err = smc_res.a0;
410 	} else {
411 		err = regmap_update_bits(hold_boot.map, hold_boot.reg,
412 					 hold_boot.mask, val);
413 	}
414 
415 	if (err)
416 		dev_err(&rproc->dev, "failed to set hold boot\n");
417 
418 	return err;
419 }
420 
421 static void stm32_rproc_add_coredump_trace(struct rproc *rproc)
422 {
423 	struct rproc_debug_trace *trace;
424 	struct rproc_dump_segment *segment;
425 	bool already_added;
426 
427 	list_for_each_entry(trace, &rproc->traces, node) {
428 		already_added = false;
429 
430 		list_for_each_entry(segment, &rproc->dump_segments, node) {
431 			if (segment->da == trace->trace_mem.da) {
432 				already_added = true;
433 				break;
434 			}
435 		}
436 
437 		if (!already_added)
438 			rproc_coredump_add_segment(rproc, trace->trace_mem.da,
439 						   trace->trace_mem.len);
440 	}
441 }
442 
443 static int stm32_rproc_start(struct rproc *rproc)
444 {
445 	struct stm32_rproc *ddata = rproc->priv;
446 	int err;
447 
448 	stm32_rproc_add_coredump_trace(rproc);
449 
450 	/* clear remote proc Deep Sleep */
451 	if (ddata->pdds.map) {
452 		err = regmap_update_bits(ddata->pdds.map, ddata->pdds.reg,
453 					 ddata->pdds.mask, 0);
454 		if (err) {
455 			dev_err(&rproc->dev, "failed to clear pdds\n");
456 			return err;
457 		}
458 	}
459 
460 	err = stm32_rproc_set_hold_boot(rproc, false);
461 	if (err)
462 		return err;
463 
464 	return stm32_rproc_set_hold_boot(rproc, true);
465 }
466 
467 static int stm32_rproc_attach(struct rproc *rproc)
468 {
469 	stm32_rproc_add_coredump_trace(rproc);
470 
471 	return stm32_rproc_set_hold_boot(rproc, true);
472 }
473 
474 static int stm32_rproc_detach(struct rproc *rproc)
475 {
476 	struct stm32_rproc *ddata = rproc->priv;
477 	int err, idx;
478 
479 	/* Inform the remote processor of the detach */
480 	idx = stm32_rproc_mbox_idx(rproc, STM32_MBX_DETACH);
481 	if (idx >= 0 && ddata->mb[idx].chan) {
482 		err = mbox_send_message(ddata->mb[idx].chan, "stop");
483 		if (err < 0)
484 			dev_warn(&rproc->dev, "warning: remote FW detach without ack\n");
485 	}
486 
487 	/* Allow remote processor to auto-reboot */
488 	return stm32_rproc_set_hold_boot(rproc, false);
489 }
490 
491 static int stm32_rproc_stop(struct rproc *rproc)
492 {
493 	struct stm32_rproc *ddata = rproc->priv;
494 	int err, idx;
495 
496 	/* request shutdown of the remote processor */
497 	if (rproc->state != RPROC_OFFLINE) {
498 		idx = stm32_rproc_mbox_idx(rproc, STM32_MBX_SHUTDOWN);
499 		if (idx >= 0 && ddata->mb[idx].chan) {
500 			err = mbox_send_message(ddata->mb[idx].chan, "detach");
501 			if (err < 0)
502 				dev_warn(&rproc->dev, "warning: remote FW shutdown without ack\n");
503 		}
504 	}
505 
506 	err = stm32_rproc_set_hold_boot(rproc, true);
507 	if (err)
508 		return err;
509 
510 	err = reset_control_assert(ddata->rst);
511 	if (err) {
512 		dev_err(&rproc->dev, "failed to assert the reset\n");
513 		return err;
514 	}
515 
516 	/* to allow platform Standby power mode, set remote proc Deep Sleep */
517 	if (ddata->pdds.map) {
518 		err = regmap_update_bits(ddata->pdds.map, ddata->pdds.reg,
519 					 ddata->pdds.mask, 1);
520 		if (err) {
521 			dev_err(&rproc->dev, "failed to set pdds\n");
522 			return err;
523 		}
524 	}
525 
526 	/* update coprocessor state to OFF if available */
527 	if (ddata->m4_state.map) {
528 		err = regmap_update_bits(ddata->m4_state.map,
529 					 ddata->m4_state.reg,
530 					 ddata->m4_state.mask,
531 					 M4_STATE_OFF);
532 		if (err) {
533 			dev_err(&rproc->dev, "failed to set copro state\n");
534 			return err;
535 		}
536 	}
537 
538 	return 0;
539 }
540 
541 static void stm32_rproc_kick(struct rproc *rproc, int vqid)
542 {
543 	struct stm32_rproc *ddata = rproc->priv;
544 	unsigned int i;
545 	int err;
546 
547 	if (WARN_ON(vqid >= MBOX_NB_VQ))
548 		return;
549 
550 	for (i = 0; i < MBOX_NB_MBX; i++) {
551 		if (vqid != ddata->mb[i].vq_id)
552 			continue;
553 		if (!ddata->mb[i].chan)
554 			return;
555 		err = mbox_send_message(ddata->mb[i].chan, "kick");
556 		if (err < 0)
557 			dev_err(&rproc->dev, "%s: failed (%s, err:%d)\n",
558 				__func__, ddata->mb[i].name, err);
559 		return;
560 	}
561 }
562 
563 static int stm32_rproc_da_to_pa(struct rproc *rproc,
564 				u64 da, phys_addr_t *pa)
565 {
566 	struct stm32_rproc *ddata = rproc->priv;
567 	struct device *dev = rproc->dev.parent;
568 	struct stm32_rproc_mem *p_mem;
569 	unsigned int i;
570 
571 	for (i = 0; i < ddata->nb_rmems; i++) {
572 		p_mem = &ddata->rmems[i];
573 
574 		if (da < p_mem->dev_addr ||
575 		    da >= p_mem->dev_addr + p_mem->size)
576 			continue;
577 
578 		*pa = da - p_mem->dev_addr + p_mem->bus_addr;
579 		dev_dbg(dev, "da %llx to pa %pap\n", da, pa);
580 
581 		return 0;
582 	}
583 
584 	dev_err(dev, "can't translate da %llx\n", da);
585 
586 	return -EINVAL;
587 }
588 
589 static struct resource_table *
590 stm32_rproc_get_loaded_rsc_table(struct rproc *rproc, size_t *table_sz)
591 {
592 	struct stm32_rproc *ddata = rproc->priv;
593 	struct device *dev = rproc->dev.parent;
594 	phys_addr_t rsc_pa;
595 	u32 rsc_da;
596 	int err;
597 
598 	/* The resource table has already been mapped, nothing to do */
599 	if (ddata->rsc_va)
600 		goto done;
601 
602 	err = regmap_read(ddata->rsctbl.map, ddata->rsctbl.reg, &rsc_da);
603 	if (err) {
604 		dev_err(dev, "failed to read rsc tbl addr\n");
605 		return ERR_PTR(-EINVAL);
606 	}
607 
608 	if (!rsc_da)
609 		/* no rsc table */
610 		return ERR_PTR(-ENOENT);
611 
612 	err = stm32_rproc_da_to_pa(rproc, rsc_da, &rsc_pa);
613 	if (err)
614 		return ERR_PTR(err);
615 
616 	ddata->rsc_va = devm_ioremap_wc(dev, rsc_pa, RSC_TBL_SIZE);
617 	if (IS_ERR_OR_NULL(ddata->rsc_va)) {
618 		dev_err(dev, "Unable to map memory region: %pa+%zx\n",
619 			&rsc_pa, RSC_TBL_SIZE);
620 		ddata->rsc_va = NULL;
621 		return ERR_PTR(-ENOMEM);
622 	}
623 
624 done:
625 	/*
626 	 * Assuming the resource table fits in 1kB is fair.
627 	 * Notice for the detach, that this 1 kB memory area has to be reserved in the coprocessor
628 	 * firmware for the resource table. On detach, the remoteproc core re-initializes this
629 	 * entire area by overwriting it with the initial values stored in rproc->clean_table.
630 	 */
631 	*table_sz = RSC_TBL_SIZE;
632 	return (struct resource_table *)ddata->rsc_va;
633 }
634 
635 static const struct rproc_ops st_rproc_ops = {
636 	.prepare	= stm32_rproc_prepare,
637 	.start		= stm32_rproc_start,
638 	.stop		= stm32_rproc_stop,
639 	.attach		= stm32_rproc_attach,
640 	.detach		= stm32_rproc_detach,
641 	.kick		= stm32_rproc_kick,
642 	.load		= rproc_elf_load_segments,
643 	.parse_fw	= stm32_rproc_parse_fw,
644 	.find_loaded_rsc_table = rproc_elf_find_loaded_rsc_table,
645 	.get_loaded_rsc_table = stm32_rproc_get_loaded_rsc_table,
646 	.sanity_check	= rproc_elf_sanity_check,
647 	.get_boot_addr	= rproc_elf_get_boot_addr,
648 };
649 
650 static const struct of_device_id stm32_rproc_match[] = {
651 	{ .compatible = "st,stm32mp1-m4" },
652 	{},
653 };
654 MODULE_DEVICE_TABLE(of, stm32_rproc_match);
655 
656 static int stm32_rproc_get_syscon(struct device_node *np, const char *prop,
657 				  struct stm32_syscon *syscon)
658 {
659 	int err = 0;
660 
661 	syscon->map = syscon_regmap_lookup_by_phandle(np, prop);
662 	if (IS_ERR(syscon->map)) {
663 		err = PTR_ERR(syscon->map);
664 		syscon->map = NULL;
665 		goto out;
666 	}
667 
668 	err = of_property_read_u32_index(np, prop, 1, &syscon->reg);
669 	if (err)
670 		goto out;
671 
672 	err = of_property_read_u32_index(np, prop, 2, &syscon->mask);
673 
674 out:
675 	return err;
676 }
677 
678 static int stm32_rproc_parse_dt(struct platform_device *pdev,
679 				struct stm32_rproc *ddata, bool *auto_boot)
680 {
681 	struct device *dev = &pdev->dev;
682 	struct device_node *np = dev->of_node;
683 	struct stm32_syscon tz;
684 	unsigned int tzen;
685 	int err, irq;
686 
687 	irq = platform_get_irq(pdev, 0);
688 	if (irq == -EPROBE_DEFER)
689 		return dev_err_probe(dev, irq, "failed to get interrupt\n");
690 
691 	if (irq > 0) {
692 		err = devm_request_irq(dev, irq, stm32_rproc_wdg, 0,
693 				       dev_name(dev), pdev);
694 		if (err)
695 			return dev_err_probe(dev, err,
696 					     "failed to request wdg irq\n");
697 
698 		ddata->wdg_irq = irq;
699 
700 		if (of_property_read_bool(np, "wakeup-source")) {
701 			device_init_wakeup(dev, true);
702 			dev_pm_set_wake_irq(dev, irq);
703 		}
704 
705 		dev_info(dev, "wdg irq registered\n");
706 	}
707 
708 	ddata->rst = devm_reset_control_get_by_index(dev, 0);
709 	if (IS_ERR(ddata->rst))
710 		return dev_err_probe(dev, PTR_ERR(ddata->rst),
711 				     "failed to get mcu_reset\n");
712 
713 	/*
714 	 * if platform is secured the hold boot bit must be written by
715 	 * smc call and read normally.
716 	 * if not secure the hold boot bit could be read/write normally
717 	 */
718 	err = stm32_rproc_get_syscon(np, "st,syscfg-tz", &tz);
719 	if (err) {
720 		dev_err(dev, "failed to get tz syscfg\n");
721 		return err;
722 	}
723 
724 	err = regmap_read(tz.map, tz.reg, &tzen);
725 	if (err) {
726 		dev_err(dev, "failed to read tzen\n");
727 		return err;
728 	}
729 	ddata->secured_soc = tzen & tz.mask;
730 
731 	err = stm32_rproc_get_syscon(np, "st,syscfg-holdboot",
732 				     &ddata->hold_boot);
733 	if (err) {
734 		dev_err(dev, "failed to get hold boot\n");
735 		return err;
736 	}
737 
738 	err = stm32_rproc_get_syscon(np, "st,syscfg-pdds", &ddata->pdds);
739 	if (err)
740 		dev_info(dev, "failed to get pdds\n");
741 
742 	*auto_boot = of_property_read_bool(np, "st,auto-boot");
743 
744 	/*
745 	 * See if we can check the M4 status, i.e if it was started
746 	 * from the boot loader or not.
747 	 */
748 	err = stm32_rproc_get_syscon(np, "st,syscfg-m4-state",
749 				     &ddata->m4_state);
750 	if (err) {
751 		/* remember this */
752 		ddata->m4_state.map = NULL;
753 		/* no coprocessor state syscon (optional) */
754 		dev_warn(dev, "m4 state not supported\n");
755 
756 		/* no need to go further */
757 		return 0;
758 	}
759 
760 	/* See if we can get the resource table */
761 	err = stm32_rproc_get_syscon(np, "st,syscfg-rsc-tbl",
762 				     &ddata->rsctbl);
763 	if (err) {
764 		/* no rsc table syscon (optional) */
765 		dev_warn(dev, "rsc tbl syscon not supported\n");
766 	}
767 
768 	return 0;
769 }
770 
771 static int stm32_rproc_get_m4_status(struct stm32_rproc *ddata,
772 				     unsigned int *state)
773 {
774 	/* See stm32_rproc_parse_dt() */
775 	if (!ddata->m4_state.map) {
776 		/*
777 		 * We couldn't get the coprocessor's state, assume
778 		 * it is not running.
779 		 */
780 		*state = M4_STATE_OFF;
781 		return 0;
782 	}
783 
784 	return regmap_read(ddata->m4_state.map, ddata->m4_state.reg, state);
785 }
786 
787 static int stm32_rproc_probe(struct platform_device *pdev)
788 {
789 	struct device *dev = &pdev->dev;
790 	struct stm32_rproc *ddata;
791 	struct device_node *np = dev->of_node;
792 	struct rproc *rproc;
793 	unsigned int state;
794 	int ret;
795 
796 	ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
797 	if (ret)
798 		return ret;
799 
800 	rproc = rproc_alloc(dev, np->name, &st_rproc_ops, NULL, sizeof(*ddata));
801 	if (!rproc)
802 		return -ENOMEM;
803 
804 	ddata = rproc->priv;
805 
806 	rproc_coredump_set_elf_info(rproc, ELFCLASS32, EM_NONE);
807 
808 	ret = stm32_rproc_parse_dt(pdev, ddata, &rproc->auto_boot);
809 	if (ret)
810 		goto free_rproc;
811 
812 	ret = stm32_rproc_of_memory_translations(pdev, ddata);
813 	if (ret)
814 		goto free_rproc;
815 
816 	ret = stm32_rproc_get_m4_status(ddata, &state);
817 	if (ret)
818 		goto free_rproc;
819 
820 	if (state == M4_STATE_CRUN)
821 		rproc->state = RPROC_DETACHED;
822 
823 	rproc->has_iommu = false;
824 	ddata->workqueue = create_workqueue(dev_name(dev));
825 	if (!ddata->workqueue) {
826 		dev_err(dev, "cannot create workqueue\n");
827 		ret = -ENOMEM;
828 		goto free_resources;
829 	}
830 
831 	platform_set_drvdata(pdev, rproc);
832 
833 	ret = stm32_rproc_request_mbox(rproc);
834 	if (ret)
835 		goto free_wkq;
836 
837 	ret = rproc_add(rproc);
838 	if (ret)
839 		goto free_mb;
840 
841 	return 0;
842 
843 free_mb:
844 	stm32_rproc_free_mbox(rproc);
845 free_wkq:
846 	destroy_workqueue(ddata->workqueue);
847 free_resources:
848 	rproc_resource_cleanup(rproc);
849 free_rproc:
850 	if (device_may_wakeup(dev)) {
851 		dev_pm_clear_wake_irq(dev);
852 		device_init_wakeup(dev, false);
853 	}
854 	rproc_free(rproc);
855 	return ret;
856 }
857 
858 static int stm32_rproc_remove(struct platform_device *pdev)
859 {
860 	struct rproc *rproc = platform_get_drvdata(pdev);
861 	struct stm32_rproc *ddata = rproc->priv;
862 	struct device *dev = &pdev->dev;
863 
864 	if (atomic_read(&rproc->power) > 0)
865 		rproc_shutdown(rproc);
866 
867 	rproc_del(rproc);
868 	stm32_rproc_free_mbox(rproc);
869 	destroy_workqueue(ddata->workqueue);
870 
871 	if (device_may_wakeup(dev)) {
872 		dev_pm_clear_wake_irq(dev);
873 		device_init_wakeup(dev, false);
874 	}
875 	rproc_free(rproc);
876 
877 	return 0;
878 }
879 
880 static int __maybe_unused stm32_rproc_suspend(struct device *dev)
881 {
882 	struct rproc *rproc = dev_get_drvdata(dev);
883 	struct stm32_rproc *ddata = rproc->priv;
884 
885 	if (device_may_wakeup(dev))
886 		return enable_irq_wake(ddata->wdg_irq);
887 
888 	return 0;
889 }
890 
891 static int __maybe_unused stm32_rproc_resume(struct device *dev)
892 {
893 	struct rproc *rproc = dev_get_drvdata(dev);
894 	struct stm32_rproc *ddata = rproc->priv;
895 
896 	if (device_may_wakeup(dev))
897 		return disable_irq_wake(ddata->wdg_irq);
898 
899 	return 0;
900 }
901 
902 static SIMPLE_DEV_PM_OPS(stm32_rproc_pm_ops,
903 			 stm32_rproc_suspend, stm32_rproc_resume);
904 
905 static struct platform_driver stm32_rproc_driver = {
906 	.probe = stm32_rproc_probe,
907 	.remove = stm32_rproc_remove,
908 	.driver = {
909 		.name = "stm32-rproc",
910 		.pm = &stm32_rproc_pm_ops,
911 		.of_match_table = of_match_ptr(stm32_rproc_match),
912 	},
913 };
914 module_platform_driver(stm32_rproc_driver);
915 
916 MODULE_DESCRIPTION("STM32 Remote Processor Control Driver");
917 MODULE_AUTHOR("Ludovic Barre <ludovic.barre@st.com>");
918 MODULE_AUTHOR("Fabien Dessenne <fabien.dessenne@st.com>");
919 MODULE_LICENSE("GPL v2");
920 
921