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		3
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 
42 #define RSC_TBL_SIZE		1024
43 
44 #define M4_STATE_OFF		0
45 #define M4_STATE_INI		1
46 #define M4_STATE_CRUN		2
47 #define M4_STATE_CSTOP		3
48 #define M4_STATE_STANDBY	4
49 #define M4_STATE_CRASH		5
50 
51 struct stm32_syscon {
52 	struct regmap *map;
53 	u32 reg;
54 	u32 mask;
55 };
56 
57 struct stm32_rproc_mem {
58 	char name[20];
59 	void __iomem *cpu_addr;
60 	phys_addr_t bus_addr;
61 	u32 dev_addr;
62 	size_t size;
63 };
64 
65 struct stm32_rproc_mem_ranges {
66 	u32 dev_addr;
67 	u32 bus_addr;
68 	u32 size;
69 };
70 
71 struct stm32_mbox {
72 	const unsigned char name[10];
73 	struct mbox_chan *chan;
74 	struct mbox_client client;
75 	struct work_struct vq_work;
76 	int vq_id;
77 };
78 
79 struct stm32_rproc {
80 	struct reset_control *rst;
81 	struct stm32_syscon hold_boot;
82 	struct stm32_syscon pdds;
83 	struct stm32_syscon m4_state;
84 	struct stm32_syscon rsctbl;
85 	int wdg_irq;
86 	u32 nb_rmems;
87 	struct stm32_rproc_mem *rmems;
88 	struct stm32_mbox mb[MBOX_NB_MBX];
89 	struct workqueue_struct *workqueue;
90 	bool secured_soc;
91 	void __iomem *rsc_va;
92 };
93 
94 static int stm32_rproc_pa_to_da(struct rproc *rproc, phys_addr_t pa, u64 *da)
95 {
96 	unsigned int i;
97 	struct stm32_rproc *ddata = rproc->priv;
98 	struct stm32_rproc_mem *p_mem;
99 
100 	for (i = 0; i < ddata->nb_rmems; i++) {
101 		p_mem = &ddata->rmems[i];
102 
103 		if (pa < p_mem->bus_addr ||
104 		    pa >= p_mem->bus_addr + p_mem->size)
105 			continue;
106 		*da = pa - p_mem->bus_addr + p_mem->dev_addr;
107 		dev_dbg(rproc->dev.parent, "pa %pa to da %llx\n", &pa, *da);
108 		return 0;
109 	}
110 
111 	return -EINVAL;
112 }
113 
114 static int stm32_rproc_mem_alloc(struct rproc *rproc,
115 				 struct rproc_mem_entry *mem)
116 {
117 	struct device *dev = rproc->dev.parent;
118 	void *va;
119 
120 	dev_dbg(dev, "map memory: %pa+%x\n", &mem->dma, mem->len);
121 	va = ioremap_wc(mem->dma, mem->len);
122 	if (IS_ERR_OR_NULL(va)) {
123 		dev_err(dev, "Unable to map memory region: %pa+%x\n",
124 			&mem->dma, mem->len);
125 		return -ENOMEM;
126 	}
127 
128 	/* Update memory entry va */
129 	mem->va = va;
130 
131 	return 0;
132 }
133 
134 static int stm32_rproc_mem_release(struct rproc *rproc,
135 				   struct rproc_mem_entry *mem)
136 {
137 	dev_dbg(rproc->dev.parent, "unmap memory: %pa\n", &mem->dma);
138 	iounmap(mem->va);
139 
140 	return 0;
141 }
142 
143 static int stm32_rproc_of_memory_translations(struct platform_device *pdev,
144 					      struct stm32_rproc *ddata)
145 {
146 	struct device *parent, *dev = &pdev->dev;
147 	struct device_node *np;
148 	struct stm32_rproc_mem *p_mems;
149 	struct stm32_rproc_mem_ranges *mem_range;
150 	int cnt, array_size, i, ret = 0;
151 
152 	parent = dev->parent;
153 	np = parent->of_node;
154 
155 	cnt = of_property_count_elems_of_size(np, "dma-ranges",
156 					      sizeof(*mem_range));
157 	if (cnt <= 0) {
158 		dev_err(dev, "%s: dma-ranges property not defined\n", __func__);
159 		return -EINVAL;
160 	}
161 
162 	p_mems = devm_kcalloc(dev, cnt, sizeof(*p_mems), GFP_KERNEL);
163 	if (!p_mems)
164 		return -ENOMEM;
165 	mem_range = kcalloc(cnt, sizeof(*mem_range), GFP_KERNEL);
166 	if (!mem_range)
167 		return -ENOMEM;
168 
169 	array_size = cnt * sizeof(struct stm32_rproc_mem_ranges) / sizeof(u32);
170 
171 	ret = of_property_read_u32_array(np, "dma-ranges",
172 					 (u32 *)mem_range, array_size);
173 	if (ret) {
174 		dev_err(dev, "error while get dma-ranges property: %x\n", ret);
175 		goto free_mem;
176 	}
177 
178 	for (i = 0; i < cnt; i++) {
179 		p_mems[i].bus_addr = mem_range[i].bus_addr;
180 		p_mems[i].dev_addr = mem_range[i].dev_addr;
181 		p_mems[i].size     = mem_range[i].size;
182 
183 		dev_dbg(dev, "memory range[%i]: da %#x, pa %pa, size %#zx:\n",
184 			i, p_mems[i].dev_addr, &p_mems[i].bus_addr,
185 			p_mems[i].size);
186 	}
187 
188 	ddata->rmems = p_mems;
189 	ddata->nb_rmems = cnt;
190 
191 free_mem:
192 	kfree(mem_range);
193 	return ret;
194 }
195 
196 static int stm32_rproc_mbox_idx(struct rproc *rproc, const unsigned char *name)
197 {
198 	struct stm32_rproc *ddata = rproc->priv;
199 	int i;
200 
201 	for (i = 0; i < ARRAY_SIZE(ddata->mb); i++) {
202 		if (!strncmp(ddata->mb[i].name, name, strlen(name)))
203 			return i;
204 	}
205 	dev_err(&rproc->dev, "mailbox %s not found\n", name);
206 
207 	return -EINVAL;
208 }
209 
210 static int stm32_rproc_elf_load_rsc_table(struct rproc *rproc,
211 					  const struct firmware *fw)
212 {
213 	if (rproc_elf_load_rsc_table(rproc, fw))
214 		dev_warn(&rproc->dev, "no resource table found for this firmware\n");
215 
216 	return 0;
217 }
218 
219 static int stm32_rproc_parse_memory_regions(struct rproc *rproc)
220 {
221 	struct device *dev = rproc->dev.parent;
222 	struct device_node *np = dev->of_node;
223 	struct of_phandle_iterator it;
224 	struct rproc_mem_entry *mem;
225 	struct reserved_mem *rmem;
226 	u64 da;
227 	int index = 0;
228 
229 	/* Register associated reserved memory regions */
230 	of_phandle_iterator_init(&it, np, "memory-region", NULL, 0);
231 	while (of_phandle_iterator_next(&it) == 0) {
232 		rmem = of_reserved_mem_lookup(it.node);
233 		if (!rmem) {
234 			dev_err(dev, "unable to acquire memory-region\n");
235 			return -EINVAL;
236 		}
237 
238 		if (stm32_rproc_pa_to_da(rproc, rmem->base, &da) < 0) {
239 			dev_err(dev, "memory region not valid %pa\n",
240 				&rmem->base);
241 			return -EINVAL;
242 		}
243 
244 		/*  No need to map vdev buffer */
245 		if (strcmp(it.node->name, "vdev0buffer")) {
246 			/* Register memory region */
247 			mem = rproc_mem_entry_init(dev, NULL,
248 						   (dma_addr_t)rmem->base,
249 						   rmem->size, da,
250 						   stm32_rproc_mem_alloc,
251 						   stm32_rproc_mem_release,
252 						   it.node->name);
253 
254 			if (mem)
255 				rproc_coredump_add_segment(rproc, da,
256 							   rmem->size);
257 		} else {
258 			/* Register reserved memory for vdev buffer alloc */
259 			mem = rproc_of_resm_mem_entry_init(dev, index,
260 							   rmem->size,
261 							   rmem->base,
262 							   it.node->name);
263 		}
264 
265 		if (!mem)
266 			return -ENOMEM;
267 
268 		rproc_add_carveout(rproc, mem);
269 		index++;
270 	}
271 
272 	return 0;
273 }
274 
275 static int stm32_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw)
276 {
277 	int ret = stm32_rproc_parse_memory_regions(rproc);
278 
279 	if (ret)
280 		return ret;
281 
282 	return stm32_rproc_elf_load_rsc_table(rproc, fw);
283 }
284 
285 static irqreturn_t stm32_rproc_wdg(int irq, void *data)
286 {
287 	struct platform_device *pdev = data;
288 	struct rproc *rproc = platform_get_drvdata(pdev);
289 
290 	rproc_report_crash(rproc, RPROC_WATCHDOG);
291 
292 	return IRQ_HANDLED;
293 }
294 
295 static void stm32_rproc_mb_vq_work(struct work_struct *work)
296 {
297 	struct stm32_mbox *mb = container_of(work, struct stm32_mbox, vq_work);
298 	struct rproc *rproc = dev_get_drvdata(mb->client.dev);
299 
300 	if (rproc_vq_interrupt(rproc, mb->vq_id) == IRQ_NONE)
301 		dev_dbg(&rproc->dev, "no message found in vq%d\n", mb->vq_id);
302 }
303 
304 static void stm32_rproc_mb_callback(struct mbox_client *cl, void *data)
305 {
306 	struct rproc *rproc = dev_get_drvdata(cl->dev);
307 	struct stm32_mbox *mb = container_of(cl, struct stm32_mbox, client);
308 	struct stm32_rproc *ddata = rproc->priv;
309 
310 	queue_work(ddata->workqueue, &mb->vq_work);
311 }
312 
313 static void stm32_rproc_free_mbox(struct rproc *rproc)
314 {
315 	struct stm32_rproc *ddata = rproc->priv;
316 	unsigned int i;
317 
318 	for (i = 0; i < ARRAY_SIZE(ddata->mb); i++) {
319 		if (ddata->mb[i].chan)
320 			mbox_free_channel(ddata->mb[i].chan);
321 		ddata->mb[i].chan = NULL;
322 	}
323 }
324 
325 static const struct stm32_mbox stm32_rproc_mbox[MBOX_NB_MBX] = {
326 	{
327 		.name = STM32_MBX_VQ0,
328 		.vq_id = STM32_MBX_VQ0_ID,
329 		.client = {
330 			.rx_callback = stm32_rproc_mb_callback,
331 			.tx_block = false,
332 		},
333 	},
334 	{
335 		.name = STM32_MBX_VQ1,
336 		.vq_id = STM32_MBX_VQ1_ID,
337 		.client = {
338 			.rx_callback = stm32_rproc_mb_callback,
339 			.tx_block = false,
340 		},
341 	},
342 	{
343 		.name = STM32_MBX_SHUTDOWN,
344 		.vq_id = -1,
345 		.client = {
346 			.tx_block = true,
347 			.tx_done = NULL,
348 			.tx_tout = 500, /* 500 ms time out */
349 		},
350 	}
351 };
352 
353 static int stm32_rproc_request_mbox(struct rproc *rproc)
354 {
355 	struct stm32_rproc *ddata = rproc->priv;
356 	struct device *dev = &rproc->dev;
357 	unsigned int i;
358 	int j;
359 	const unsigned char *name;
360 	struct mbox_client *cl;
361 
362 	/* Initialise mailbox structure table */
363 	memcpy(ddata->mb, stm32_rproc_mbox, sizeof(stm32_rproc_mbox));
364 
365 	for (i = 0; i < MBOX_NB_MBX; i++) {
366 		name = ddata->mb[i].name;
367 
368 		cl = &ddata->mb[i].client;
369 		cl->dev = dev->parent;
370 
371 		ddata->mb[i].chan = mbox_request_channel_byname(cl, name);
372 		if (IS_ERR(ddata->mb[i].chan)) {
373 			if (PTR_ERR(ddata->mb[i].chan) == -EPROBE_DEFER) {
374 				dev_err_probe(dev->parent,
375 					      PTR_ERR(ddata->mb[i].chan),
376 					      "failed to request mailbox %s\n",
377 					      name);
378 				goto err_probe;
379 			}
380 			dev_warn(dev, "cannot get %s mbox\n", name);
381 			ddata->mb[i].chan = NULL;
382 		}
383 		if (ddata->mb[i].vq_id >= 0) {
384 			INIT_WORK(&ddata->mb[i].vq_work,
385 				  stm32_rproc_mb_vq_work);
386 		}
387 	}
388 
389 	return 0;
390 
391 err_probe:
392 	for (j = i - 1; j >= 0; j--)
393 		if (ddata->mb[j].chan)
394 			mbox_free_channel(ddata->mb[j].chan);
395 	return -EPROBE_DEFER;
396 }
397 
398 static int stm32_rproc_set_hold_boot(struct rproc *rproc, bool hold)
399 {
400 	struct stm32_rproc *ddata = rproc->priv;
401 	struct stm32_syscon hold_boot = ddata->hold_boot;
402 	struct arm_smccc_res smc_res;
403 	int val, err;
404 
405 	val = hold ? HOLD_BOOT : RELEASE_BOOT;
406 
407 	if (IS_ENABLED(CONFIG_HAVE_ARM_SMCCC) && ddata->secured_soc) {
408 		arm_smccc_smc(STM32_SMC_RCC, STM32_SMC_REG_WRITE,
409 			      hold_boot.reg, val, 0, 0, 0, 0, &smc_res);
410 		err = smc_res.a0;
411 	} else {
412 		err = regmap_update_bits(hold_boot.map, hold_boot.reg,
413 					 hold_boot.mask, val);
414 	}
415 
416 	if (err)
417 		dev_err(&rproc->dev, "failed to set hold boot\n");
418 
419 	return err;
420 }
421 
422 static void stm32_rproc_add_coredump_trace(struct rproc *rproc)
423 {
424 	struct rproc_debug_trace *trace;
425 	struct rproc_dump_segment *segment;
426 	bool already_added;
427 
428 	list_for_each_entry(trace, &rproc->traces, node) {
429 		already_added = false;
430 
431 		list_for_each_entry(segment, &rproc->dump_segments, node) {
432 			if (segment->da == trace->trace_mem.da) {
433 				already_added = true;
434 				break;
435 			}
436 		}
437 
438 		if (!already_added)
439 			rproc_coredump_add_segment(rproc, trace->trace_mem.da,
440 						   trace->trace_mem.len);
441 	}
442 }
443 
444 static int stm32_rproc_start(struct rproc *rproc)
445 {
446 	struct stm32_rproc *ddata = rproc->priv;
447 	int err;
448 
449 	stm32_rproc_add_coredump_trace(rproc);
450 
451 	/* clear remote proc Deep Sleep */
452 	if (ddata->pdds.map) {
453 		err = regmap_update_bits(ddata->pdds.map, ddata->pdds.reg,
454 					 ddata->pdds.mask, 0);
455 		if (err) {
456 			dev_err(&rproc->dev, "failed to clear pdds\n");
457 			return err;
458 		}
459 	}
460 
461 	err = stm32_rproc_set_hold_boot(rproc, false);
462 	if (err)
463 		return err;
464 
465 	return stm32_rproc_set_hold_boot(rproc, true);
466 }
467 
468 static int stm32_rproc_attach(struct rproc *rproc)
469 {
470 	stm32_rproc_add_coredump_trace(rproc);
471 
472 	return stm32_rproc_set_hold_boot(rproc, true);
473 }
474 
475 static int stm32_rproc_stop(struct rproc *rproc)
476 {
477 	struct stm32_rproc *ddata = rproc->priv;
478 	int err, dummy_data, idx;
479 
480 	/* request shutdown of the remote processor */
481 	if (rproc->state != RPROC_OFFLINE) {
482 		idx = stm32_rproc_mbox_idx(rproc, STM32_MBX_SHUTDOWN);
483 		if (idx >= 0 && ddata->mb[idx].chan) {
484 			/* a dummy data is sent to allow to block on transmit */
485 			err = mbox_send_message(ddata->mb[idx].chan,
486 						&dummy_data);
487 			if (err < 0)
488 				dev_warn(&rproc->dev, "warning: remote FW shutdown without ack\n");
489 		}
490 	}
491 
492 	err = stm32_rproc_set_hold_boot(rproc, true);
493 	if (err)
494 		return err;
495 
496 	err = reset_control_assert(ddata->rst);
497 	if (err) {
498 		dev_err(&rproc->dev, "failed to assert the reset\n");
499 		return err;
500 	}
501 
502 	/* to allow platform Standby power mode, set remote proc Deep Sleep */
503 	if (ddata->pdds.map) {
504 		err = regmap_update_bits(ddata->pdds.map, ddata->pdds.reg,
505 					 ddata->pdds.mask, 1);
506 		if (err) {
507 			dev_err(&rproc->dev, "failed to set pdds\n");
508 			return err;
509 		}
510 	}
511 
512 	/* update coprocessor state to OFF if available */
513 	if (ddata->m4_state.map) {
514 		err = regmap_update_bits(ddata->m4_state.map,
515 					 ddata->m4_state.reg,
516 					 ddata->m4_state.mask,
517 					 M4_STATE_OFF);
518 		if (err) {
519 			dev_err(&rproc->dev, "failed to set copro state\n");
520 			return err;
521 		}
522 	}
523 
524 	return 0;
525 }
526 
527 static void stm32_rproc_kick(struct rproc *rproc, int vqid)
528 {
529 	struct stm32_rproc *ddata = rproc->priv;
530 	unsigned int i;
531 	int err;
532 
533 	if (WARN_ON(vqid >= MBOX_NB_VQ))
534 		return;
535 
536 	for (i = 0; i < MBOX_NB_MBX; i++) {
537 		if (vqid != ddata->mb[i].vq_id)
538 			continue;
539 		if (!ddata->mb[i].chan)
540 			return;
541 		err = mbox_send_message(ddata->mb[i].chan, (void *)(long)vqid);
542 		if (err < 0)
543 			dev_err(&rproc->dev, "%s: failed (%s, err:%d)\n",
544 				__func__, ddata->mb[i].name, err);
545 		return;
546 	}
547 }
548 
549 static const struct rproc_ops st_rproc_ops = {
550 	.start		= stm32_rproc_start,
551 	.stop		= stm32_rproc_stop,
552 	.attach		= stm32_rproc_attach,
553 	.kick		= stm32_rproc_kick,
554 	.load		= rproc_elf_load_segments,
555 	.parse_fw	= stm32_rproc_parse_fw,
556 	.find_loaded_rsc_table = rproc_elf_find_loaded_rsc_table,
557 	.sanity_check	= rproc_elf_sanity_check,
558 	.get_boot_addr	= rproc_elf_get_boot_addr,
559 };
560 
561 static const struct of_device_id stm32_rproc_match[] = {
562 	{ .compatible = "st,stm32mp1-m4" },
563 	{},
564 };
565 MODULE_DEVICE_TABLE(of, stm32_rproc_match);
566 
567 static int stm32_rproc_get_syscon(struct device_node *np, const char *prop,
568 				  struct stm32_syscon *syscon)
569 {
570 	int err = 0;
571 
572 	syscon->map = syscon_regmap_lookup_by_phandle(np, prop);
573 	if (IS_ERR(syscon->map)) {
574 		err = PTR_ERR(syscon->map);
575 		syscon->map = NULL;
576 		goto out;
577 	}
578 
579 	err = of_property_read_u32_index(np, prop, 1, &syscon->reg);
580 	if (err)
581 		goto out;
582 
583 	err = of_property_read_u32_index(np, prop, 2, &syscon->mask);
584 
585 out:
586 	return err;
587 }
588 
589 static int stm32_rproc_parse_dt(struct platform_device *pdev,
590 				struct stm32_rproc *ddata, bool *auto_boot)
591 {
592 	struct device *dev = &pdev->dev;
593 	struct device_node *np = dev->of_node;
594 	struct stm32_syscon tz;
595 	unsigned int tzen;
596 	int err, irq;
597 
598 	irq = platform_get_irq(pdev, 0);
599 	if (irq == -EPROBE_DEFER)
600 		return dev_err_probe(dev, irq, "failed to get interrupt\n");
601 
602 	if (irq > 0) {
603 		err = devm_request_irq(dev, irq, stm32_rproc_wdg, 0,
604 				       dev_name(dev), pdev);
605 		if (err)
606 			return dev_err_probe(dev, err,
607 					     "failed to request wdg irq\n");
608 
609 		ddata->wdg_irq = irq;
610 
611 		if (of_property_read_bool(np, "wakeup-source")) {
612 			device_init_wakeup(dev, true);
613 			dev_pm_set_wake_irq(dev, irq);
614 		}
615 
616 		dev_info(dev, "wdg irq registered\n");
617 	}
618 
619 	ddata->rst = devm_reset_control_get_by_index(dev, 0);
620 	if (IS_ERR(ddata->rst))
621 		return dev_err_probe(dev, PTR_ERR(ddata->rst),
622 				     "failed to get mcu_reset\n");
623 
624 	/*
625 	 * if platform is secured the hold boot bit must be written by
626 	 * smc call and read normally.
627 	 * if not secure the hold boot bit could be read/write normally
628 	 */
629 	err = stm32_rproc_get_syscon(np, "st,syscfg-tz", &tz);
630 	if (err) {
631 		dev_err(dev, "failed to get tz syscfg\n");
632 		return err;
633 	}
634 
635 	err = regmap_read(tz.map, tz.reg, &tzen);
636 	if (err) {
637 		dev_err(dev, "failed to read tzen\n");
638 		return err;
639 	}
640 	ddata->secured_soc = tzen & tz.mask;
641 
642 	err = stm32_rproc_get_syscon(np, "st,syscfg-holdboot",
643 				     &ddata->hold_boot);
644 	if (err) {
645 		dev_err(dev, "failed to get hold boot\n");
646 		return err;
647 	}
648 
649 	err = stm32_rproc_get_syscon(np, "st,syscfg-pdds", &ddata->pdds);
650 	if (err)
651 		dev_info(dev, "failed to get pdds\n");
652 
653 	*auto_boot = of_property_read_bool(np, "st,auto-boot");
654 
655 	/*
656 	 * See if we can check the M4 status, i.e if it was started
657 	 * from the boot loader or not.
658 	 */
659 	err = stm32_rproc_get_syscon(np, "st,syscfg-m4-state",
660 				     &ddata->m4_state);
661 	if (err) {
662 		/* remember this */
663 		ddata->m4_state.map = NULL;
664 		/* no coprocessor state syscon (optional) */
665 		dev_warn(dev, "m4 state not supported\n");
666 
667 		/* no need to go further */
668 		return 0;
669 	}
670 
671 	/* See if we can get the resource table */
672 	err = stm32_rproc_get_syscon(np, "st,syscfg-rsc-tbl",
673 				     &ddata->rsctbl);
674 	if (err) {
675 		/* no rsc table syscon (optional) */
676 		dev_warn(dev, "rsc tbl syscon not supported\n");
677 	}
678 
679 	return 0;
680 }
681 
682 static int stm32_rproc_get_m4_status(struct stm32_rproc *ddata,
683 				     unsigned int *state)
684 {
685 	/* See stm32_rproc_parse_dt() */
686 	if (!ddata->m4_state.map) {
687 		/*
688 		 * We couldn't get the coprocessor's state, assume
689 		 * it is not running.
690 		 */
691 		*state = M4_STATE_OFF;
692 		return 0;
693 	}
694 
695 	return regmap_read(ddata->m4_state.map, ddata->m4_state.reg, state);
696 }
697 
698 static int stm32_rproc_da_to_pa(struct platform_device *pdev,
699 				struct stm32_rproc *ddata,
700 				u64 da, phys_addr_t *pa)
701 {
702 	struct device *dev = &pdev->dev;
703 	struct stm32_rproc_mem *p_mem;
704 	unsigned int i;
705 
706 	for (i = 0; i < ddata->nb_rmems; i++) {
707 		p_mem = &ddata->rmems[i];
708 
709 		if (da < p_mem->dev_addr ||
710 		    da >= p_mem->dev_addr + p_mem->size)
711 			continue;
712 
713 		*pa = da - p_mem->dev_addr + p_mem->bus_addr;
714 		dev_dbg(dev, "da %llx to pa %#x\n", da, *pa);
715 
716 		return 0;
717 	}
718 
719 	dev_err(dev, "can't translate da %llx\n", da);
720 
721 	return -EINVAL;
722 }
723 
724 static int stm32_rproc_get_loaded_rsc_table(struct platform_device *pdev,
725 					    struct rproc *rproc,
726 					    struct stm32_rproc *ddata)
727 {
728 	struct device *dev = &pdev->dev;
729 	phys_addr_t rsc_pa;
730 	u32 rsc_da;
731 	int err;
732 
733 	err = regmap_read(ddata->rsctbl.map, ddata->rsctbl.reg, &rsc_da);
734 	if (err) {
735 		dev_err(dev, "failed to read rsc tbl addr\n");
736 		return err;
737 	}
738 
739 	if (!rsc_da)
740 		/* no rsc table */
741 		return 0;
742 
743 	err = stm32_rproc_da_to_pa(pdev, ddata, rsc_da, &rsc_pa);
744 	if (err)
745 		return err;
746 
747 	ddata->rsc_va = devm_ioremap_wc(dev, rsc_pa, RSC_TBL_SIZE);
748 	if (IS_ERR_OR_NULL(ddata->rsc_va)) {
749 		dev_err(dev, "Unable to map memory region: %pa+%zx\n",
750 			&rsc_pa, RSC_TBL_SIZE);
751 		ddata->rsc_va = NULL;
752 		return -ENOMEM;
753 	}
754 
755 	/*
756 	 * The resource table is already loaded in device memory, no need
757 	 * to work with a cached table.
758 	 */
759 	rproc->cached_table = NULL;
760 	/* Assuming the resource table fits in 1kB is fair */
761 	rproc->table_sz = RSC_TBL_SIZE;
762 	rproc->table_ptr = (struct resource_table *)ddata->rsc_va;
763 
764 	return 0;
765 }
766 
767 static int stm32_rproc_probe(struct platform_device *pdev)
768 {
769 	struct device *dev = &pdev->dev;
770 	struct stm32_rproc *ddata;
771 	struct device_node *np = dev->of_node;
772 	struct rproc *rproc;
773 	unsigned int state;
774 	int ret;
775 
776 	ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
777 	if (ret)
778 		return ret;
779 
780 	rproc = rproc_alloc(dev, np->name, &st_rproc_ops, NULL, sizeof(*ddata));
781 	if (!rproc)
782 		return -ENOMEM;
783 
784 	ddata = rproc->priv;
785 
786 	rproc_coredump_set_elf_info(rproc, ELFCLASS32, EM_NONE);
787 
788 	ret = stm32_rproc_parse_dt(pdev, ddata, &rproc->auto_boot);
789 	if (ret)
790 		goto free_rproc;
791 
792 	ret = stm32_rproc_of_memory_translations(pdev, ddata);
793 	if (ret)
794 		goto free_rproc;
795 
796 	ret = stm32_rproc_get_m4_status(ddata, &state);
797 	if (ret)
798 		goto free_rproc;
799 
800 	if (state == M4_STATE_CRUN) {
801 		rproc->state = RPROC_DETACHED;
802 
803 		ret = stm32_rproc_parse_memory_regions(rproc);
804 		if (ret)
805 			goto free_resources;
806 
807 		ret = stm32_rproc_get_loaded_rsc_table(pdev, rproc, ddata);
808 		if (ret)
809 			goto free_resources;
810 	}
811 
812 	rproc->has_iommu = false;
813 	ddata->workqueue = create_workqueue(dev_name(dev));
814 	if (!ddata->workqueue) {
815 		dev_err(dev, "cannot create workqueue\n");
816 		ret = -ENOMEM;
817 		goto free_resources;
818 	}
819 
820 	platform_set_drvdata(pdev, rproc);
821 
822 	ret = stm32_rproc_request_mbox(rproc);
823 	if (ret)
824 		goto free_wkq;
825 
826 	ret = rproc_add(rproc);
827 	if (ret)
828 		goto free_mb;
829 
830 	return 0;
831 
832 free_mb:
833 	stm32_rproc_free_mbox(rproc);
834 free_wkq:
835 	destroy_workqueue(ddata->workqueue);
836 free_resources:
837 	rproc_resource_cleanup(rproc);
838 free_rproc:
839 	if (device_may_wakeup(dev)) {
840 		dev_pm_clear_wake_irq(dev);
841 		device_init_wakeup(dev, false);
842 	}
843 	rproc_free(rproc);
844 	return ret;
845 }
846 
847 static int stm32_rproc_remove(struct platform_device *pdev)
848 {
849 	struct rproc *rproc = platform_get_drvdata(pdev);
850 	struct stm32_rproc *ddata = rproc->priv;
851 	struct device *dev = &pdev->dev;
852 
853 	if (atomic_read(&rproc->power) > 0)
854 		rproc_shutdown(rproc);
855 
856 	rproc_del(rproc);
857 	stm32_rproc_free_mbox(rproc);
858 	destroy_workqueue(ddata->workqueue);
859 
860 	if (device_may_wakeup(dev)) {
861 		dev_pm_clear_wake_irq(dev);
862 		device_init_wakeup(dev, false);
863 	}
864 	rproc_free(rproc);
865 
866 	return 0;
867 }
868 
869 static int __maybe_unused stm32_rproc_suspend(struct device *dev)
870 {
871 	struct rproc *rproc = dev_get_drvdata(dev);
872 	struct stm32_rproc *ddata = rproc->priv;
873 
874 	if (device_may_wakeup(dev))
875 		return enable_irq_wake(ddata->wdg_irq);
876 
877 	return 0;
878 }
879 
880 static int __maybe_unused stm32_rproc_resume(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 disable_irq_wake(ddata->wdg_irq);
887 
888 	return 0;
889 }
890 
891 static SIMPLE_DEV_PM_OPS(stm32_rproc_pm_ops,
892 			 stm32_rproc_suspend, stm32_rproc_resume);
893 
894 static struct platform_driver stm32_rproc_driver = {
895 	.probe = stm32_rproc_probe,
896 	.remove = stm32_rproc_remove,
897 	.driver = {
898 		.name = "stm32-rproc",
899 		.pm = &stm32_rproc_pm_ops,
900 		.of_match_table = of_match_ptr(stm32_rproc_match),
901 	},
902 };
903 module_platform_driver(stm32_rproc_driver);
904 
905 MODULE_DESCRIPTION("STM32 Remote Processor Control Driver");
906 MODULE_AUTHOR("Ludovic Barre <ludovic.barre@st.com>");
907 MODULE_AUTHOR("Fabien Dessenne <fabien.dessenne@st.com>");
908 MODULE_LICENSE("GPL v2");
909 
910