xref: /linux/drivers/remoteproc/stm32_rproc.c (revision 7db28abbea0f7dc1ec4fdfdc149db5fbd9e4c994)
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.h>
16 #include <linux/of_reserved_mem.h>
17 #include <linux/platform_device.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 reset_control *hold_boot_rst;
83 	struct stm32_syscon hold_boot;
84 	struct stm32_syscon pdds;
85 	struct stm32_syscon m4_state;
86 	struct stm32_syscon rsctbl;
87 	int wdg_irq;
88 	u32 nb_rmems;
89 	struct stm32_rproc_mem *rmems;
90 	struct stm32_mbox mb[MBOX_NB_MBX];
91 	struct workqueue_struct *workqueue;
92 	bool hold_boot_smc;
93 	void __iomem *rsc_va;
94 };
95 
96 static int stm32_rproc_pa_to_da(struct rproc *rproc, phys_addr_t pa, u64 *da)
97 {
98 	unsigned int i;
99 	struct stm32_rproc *ddata = rproc->priv;
100 	struct stm32_rproc_mem *p_mem;
101 
102 	for (i = 0; i < ddata->nb_rmems; i++) {
103 		p_mem = &ddata->rmems[i];
104 
105 		if (pa < p_mem->bus_addr ||
106 		    pa >= p_mem->bus_addr + p_mem->size)
107 			continue;
108 		*da = pa - p_mem->bus_addr + p_mem->dev_addr;
109 		dev_dbg(rproc->dev.parent, "pa %pa to da %llx\n", &pa, *da);
110 		return 0;
111 	}
112 
113 	return -EINVAL;
114 }
115 
116 static int stm32_rproc_of_memory_translations(struct platform_device *pdev,
117 					      struct stm32_rproc *ddata)
118 {
119 	struct device *parent, *dev = &pdev->dev;
120 	struct device_node *np;
121 	struct stm32_rproc_mem *p_mems;
122 	struct stm32_rproc_mem_ranges *mem_range;
123 	int cnt, array_size, i, ret = 0;
124 
125 	parent = dev->parent;
126 	np = parent->of_node;
127 
128 	cnt = of_property_count_elems_of_size(np, "dma-ranges",
129 					      sizeof(*mem_range));
130 	if (cnt <= 0) {
131 		dev_err(dev, "%s: dma-ranges property not defined\n", __func__);
132 		return -EINVAL;
133 	}
134 
135 	p_mems = devm_kcalloc(dev, cnt, sizeof(*p_mems), GFP_KERNEL);
136 	if (!p_mems)
137 		return -ENOMEM;
138 	mem_range = kzalloc_objs(*mem_range, cnt);
139 	if (!mem_range)
140 		return -ENOMEM;
141 
142 	array_size = cnt * sizeof(struct stm32_rproc_mem_ranges) / sizeof(u32);
143 
144 	ret = of_property_read_u32_array(np, "dma-ranges",
145 					 (u32 *)mem_range, array_size);
146 	if (ret) {
147 		dev_err(dev, "error while get dma-ranges property: %x\n", ret);
148 		goto free_mem;
149 	}
150 
151 	for (i = 0; i < cnt; i++) {
152 		p_mems[i].bus_addr = mem_range[i].bus_addr;
153 		p_mems[i].dev_addr = mem_range[i].dev_addr;
154 		p_mems[i].size     = mem_range[i].size;
155 
156 		dev_dbg(dev, "memory range[%i]: da %#x, pa %pa, size %#zx:\n",
157 			i, p_mems[i].dev_addr, &p_mems[i].bus_addr,
158 			p_mems[i].size);
159 	}
160 
161 	ddata->rmems = p_mems;
162 	ddata->nb_rmems = cnt;
163 
164 free_mem:
165 	kfree(mem_range);
166 	return ret;
167 }
168 
169 static int stm32_rproc_mbox_idx(struct rproc *rproc, const unsigned char *name)
170 {
171 	struct stm32_rproc *ddata = rproc->priv;
172 	int i;
173 
174 	for (i = 0; i < ARRAY_SIZE(ddata->mb); i++) {
175 		if (!strncmp(ddata->mb[i].name, name, strlen(name)))
176 			return i;
177 	}
178 	dev_err(&rproc->dev, "mailbox %s not found\n", name);
179 
180 	return -EINVAL;
181 }
182 
183 static int stm32_rproc_prepare(struct rproc *rproc)
184 {
185 	struct device *dev = rproc->dev.parent;
186 	struct device_node *np = dev->of_node;
187 	struct rproc_mem_entry *mem;
188 	u64 da;
189 	int index = 0, mr = 0;
190 
191 	/* Register associated reserved memory regions */
192 	while (1) {
193 		struct resource res;
194 		int ret;
195 
196 		ret = of_reserved_mem_region_to_resource(np, mr++, &res);
197 		if (ret)
198 			return 0;
199 
200 		if (stm32_rproc_pa_to_da(rproc, res.start, &da) < 0) {
201 			dev_err(dev, "memory region not valid %pR\n", &res);
202 			return -EINVAL;
203 		}
204 
205 		/*  No need to map vdev buffer */
206 		if (!strstarts(res.name, "vdev0buffer")) {
207 			/* Register memory region */
208 			mem = rproc_mem_entry_init(dev, NULL,
209 						   (dma_addr_t)res.start,
210 						   resource_size(&res), da,
211 						   rproc_mem_entry_ioremap_wc,
212 						   rproc_mem_entry_iounmap,
213 						   "%.*s", strchrnul(res.name, '@') - res.name,
214 						   res.name);
215 			if (mem)
216 				rproc_coredump_add_segment(rproc, da,
217 							   resource_size(&res));
218 		} else {
219 			/* Register reserved memory for vdev buffer alloc */
220 			mem = rproc_of_resm_mem_entry_init(dev, index,
221 							   resource_size(&res),
222 							   res.start,
223 							   "vdev0buffer");
224 		}
225 
226 		if (!mem) {
227 			return -ENOMEM;
228 		}
229 
230 		rproc_add_carveout(rproc, mem);
231 		index++;
232 	}
233 }
234 
235 static int stm32_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw)
236 {
237 	rproc_elf_load_rsc_table_optional(rproc, fw, dev_warn,
238 					  "no resource table found for this firmware\n");
239 	return 0;
240 }
241 
242 static irqreturn_t stm32_rproc_wdg(int irq, void *data)
243 {
244 	struct platform_device *pdev = data;
245 	struct rproc *rproc = platform_get_drvdata(pdev);
246 
247 	rproc_report_crash(rproc, RPROC_WATCHDOG);
248 
249 	return IRQ_HANDLED;
250 }
251 
252 static void stm32_rproc_mb_vq_work(struct work_struct *work)
253 {
254 	struct stm32_mbox *mb = container_of(work, struct stm32_mbox, vq_work);
255 	struct rproc *rproc = dev_get_drvdata(mb->client.dev);
256 
257 	mutex_lock(&rproc->lock);
258 
259 	if (rproc->state != RPROC_RUNNING && rproc->state != RPROC_ATTACHED)
260 		goto unlock_mutex;
261 
262 	if (rproc_vq_interrupt(rproc, mb->vq_id) == IRQ_NONE)
263 		dev_dbg(&rproc->dev, "no message found in vq%d\n", mb->vq_id);
264 
265 unlock_mutex:
266 	mutex_unlock(&rproc->lock);
267 }
268 
269 static void stm32_rproc_mb_callback(struct mbox_client *cl, void *data)
270 {
271 	struct rproc *rproc = dev_get_drvdata(cl->dev);
272 	struct stm32_mbox *mb = container_of(cl, struct stm32_mbox, client);
273 	struct stm32_rproc *ddata = rproc->priv;
274 
275 	queue_work(ddata->workqueue, &mb->vq_work);
276 }
277 
278 static void stm32_rproc_free_mbox(struct rproc *rproc)
279 {
280 	struct stm32_rproc *ddata = rproc->priv;
281 	unsigned int i;
282 
283 	for (i = 0; i < ARRAY_SIZE(ddata->mb); i++) {
284 		if (ddata->mb[i].chan)
285 			mbox_free_channel(ddata->mb[i].chan);
286 		ddata->mb[i].chan = NULL;
287 	}
288 }
289 
290 static const struct stm32_mbox stm32_rproc_mbox[MBOX_NB_MBX] = {
291 	{
292 		.name = STM32_MBX_VQ0,
293 		.vq_id = STM32_MBX_VQ0_ID,
294 		.client = {
295 			.rx_callback = stm32_rproc_mb_callback,
296 			.tx_block = false,
297 		},
298 	},
299 	{
300 		.name = STM32_MBX_VQ1,
301 		.vq_id = STM32_MBX_VQ1_ID,
302 		.client = {
303 			.rx_callback = stm32_rproc_mb_callback,
304 			.tx_block = false,
305 		},
306 	},
307 	{
308 		.name = STM32_MBX_SHUTDOWN,
309 		.vq_id = -1,
310 		.client = {
311 			.tx_block = true,
312 			.tx_done = NULL,
313 			.tx_tout = 500, /* 500 ms time out */
314 		},
315 	},
316 	{
317 		.name = STM32_MBX_DETACH,
318 		.vq_id = -1,
319 		.client = {
320 			.tx_block = true,
321 			.tx_done = NULL,
322 			.tx_tout = 200, /* 200 ms time out to detach should be fair enough */
323 		},
324 	}
325 };
326 
327 static int stm32_rproc_request_mbox(struct rproc *rproc)
328 {
329 	struct stm32_rproc *ddata = rproc->priv;
330 	struct device *dev = &rproc->dev;
331 	unsigned int i;
332 	int j;
333 	const unsigned char *name;
334 	struct mbox_client *cl;
335 
336 	/* Initialise mailbox structure table */
337 	memcpy(ddata->mb, stm32_rproc_mbox, sizeof(stm32_rproc_mbox));
338 
339 	for (i = 0; i < MBOX_NB_MBX; i++) {
340 		name = ddata->mb[i].name;
341 
342 		cl = &ddata->mb[i].client;
343 		cl->dev = dev->parent;
344 
345 		ddata->mb[i].chan = mbox_request_channel_byname(cl, name);
346 		if (IS_ERR(ddata->mb[i].chan)) {
347 			if (PTR_ERR(ddata->mb[i].chan) == -EPROBE_DEFER) {
348 				dev_err_probe(dev->parent,
349 					      PTR_ERR(ddata->mb[i].chan),
350 					      "failed to request mailbox %s\n",
351 					      name);
352 				goto err_probe;
353 			}
354 			dev_warn(dev, "cannot get %s mbox\n", name);
355 			ddata->mb[i].chan = NULL;
356 		}
357 		if (ddata->mb[i].vq_id >= 0) {
358 			INIT_WORK(&ddata->mb[i].vq_work,
359 				  stm32_rproc_mb_vq_work);
360 		}
361 	}
362 
363 	return 0;
364 
365 err_probe:
366 	for (j = i - 1; j >= 0; j--)
367 		if (ddata->mb[j].chan)
368 			mbox_free_channel(ddata->mb[j].chan);
369 	return -EPROBE_DEFER;
370 }
371 
372 static int stm32_rproc_set_hold_boot(struct rproc *rproc, bool hold)
373 {
374 	struct stm32_rproc *ddata = rproc->priv;
375 	struct stm32_syscon hold_boot = ddata->hold_boot;
376 	struct arm_smccc_res smc_res;
377 	int val, err;
378 
379 	/*
380 	 * Three ways to manage the hold boot
381 	 * - using SCMI: the hold boot is managed as a reset,
382 	 * - using Linux(no SCMI): the hold boot is managed as a syscon register
383 	 * - using SMC call (deprecated): use SMC reset interface
384 	 */
385 
386 	val = hold ? HOLD_BOOT : RELEASE_BOOT;
387 
388 	if (ddata->hold_boot_rst) {
389 		/* Use the SCMI reset controller */
390 		if (!hold)
391 			err = reset_control_deassert(ddata->hold_boot_rst);
392 		else
393 			err =  reset_control_assert(ddata->hold_boot_rst);
394 	} else if (IS_ENABLED(CONFIG_HAVE_ARM_SMCCC) && ddata->hold_boot_smc) {
395 		/* Use the SMC call */
396 		arm_smccc_smc(STM32_SMC_RCC, STM32_SMC_REG_WRITE,
397 			      hold_boot.reg, val, 0, 0, 0, 0, &smc_res);
398 		err = smc_res.a0;
399 	} else {
400 		/* Use syscon */
401 		err = regmap_update_bits(hold_boot.map, hold_boot.reg,
402 					 hold_boot.mask, val);
403 	}
404 
405 	if (err)
406 		dev_err(&rproc->dev, "failed to set hold boot\n");
407 
408 	return err;
409 }
410 
411 static void stm32_rproc_add_coredump_trace(struct rproc *rproc)
412 {
413 	struct rproc_debug_trace *trace;
414 	struct rproc_dump_segment *segment;
415 	bool already_added;
416 
417 	list_for_each_entry(trace, &rproc->traces, node) {
418 		already_added = false;
419 
420 		list_for_each_entry(segment, &rproc->dump_segments, node) {
421 			if (segment->da == trace->trace_mem.da) {
422 				already_added = true;
423 				break;
424 			}
425 		}
426 
427 		if (!already_added)
428 			rproc_coredump_add_segment(rproc, trace->trace_mem.da,
429 						   trace->trace_mem.len);
430 	}
431 }
432 
433 static int stm32_rproc_start(struct rproc *rproc)
434 {
435 	struct stm32_rproc *ddata = rproc->priv;
436 	int err;
437 
438 	stm32_rproc_add_coredump_trace(rproc);
439 
440 	/* clear remote proc Deep Sleep */
441 	if (ddata->pdds.map) {
442 		err = regmap_update_bits(ddata->pdds.map, ddata->pdds.reg,
443 					 ddata->pdds.mask, 0);
444 		if (err) {
445 			dev_err(&rproc->dev, "failed to clear pdds\n");
446 			return err;
447 		}
448 	}
449 
450 	err = stm32_rproc_set_hold_boot(rproc, false);
451 	if (err)
452 		return err;
453 
454 	return stm32_rproc_set_hold_boot(rproc, true);
455 }
456 
457 static int stm32_rproc_attach(struct rproc *rproc)
458 {
459 	stm32_rproc_add_coredump_trace(rproc);
460 
461 	return stm32_rproc_set_hold_boot(rproc, true);
462 }
463 
464 static int stm32_rproc_detach(struct rproc *rproc)
465 {
466 	struct stm32_rproc *ddata = rproc->priv;
467 	int err, idx;
468 
469 	/* Inform the remote processor of the detach */
470 	idx = stm32_rproc_mbox_idx(rproc, STM32_MBX_DETACH);
471 	if (idx >= 0 && ddata->mb[idx].chan) {
472 		err = mbox_send_message(ddata->mb[idx].chan, "stop");
473 		if (err < 0)
474 			dev_warn(&rproc->dev, "warning: remote FW detach without ack\n");
475 	}
476 
477 	/* Allow remote processor to auto-reboot */
478 	return stm32_rproc_set_hold_boot(rproc, false);
479 }
480 
481 static int stm32_rproc_stop(struct rproc *rproc)
482 {
483 	struct stm32_rproc *ddata = rproc->priv;
484 	int err, idx;
485 
486 	/* request shutdown of the remote processor */
487 	if (rproc->state != RPROC_OFFLINE && rproc->state != RPROC_CRASHED) {
488 		idx = stm32_rproc_mbox_idx(rproc, STM32_MBX_SHUTDOWN);
489 		if (idx >= 0 && ddata->mb[idx].chan) {
490 			err = mbox_send_message(ddata->mb[idx].chan, "detach");
491 			if (err < 0)
492 				dev_warn(&rproc->dev, "warning: remote FW shutdown without ack\n");
493 		}
494 	}
495 
496 	err = stm32_rproc_set_hold_boot(rproc, true);
497 	if (err)
498 		return err;
499 
500 	err = reset_control_assert(ddata->rst);
501 	if (err) {
502 		dev_err(&rproc->dev, "failed to assert the reset\n");
503 		return err;
504 	}
505 
506 	/* to allow platform Standby power mode, set remote proc Deep Sleep */
507 	if (ddata->pdds.map) {
508 		err = regmap_update_bits(ddata->pdds.map, ddata->pdds.reg,
509 					 ddata->pdds.mask, 1);
510 		if (err) {
511 			dev_err(&rproc->dev, "failed to set pdds\n");
512 			return err;
513 		}
514 	}
515 
516 	/* update coprocessor state to OFF if available */
517 	if (ddata->m4_state.map) {
518 		err = regmap_update_bits(ddata->m4_state.map,
519 					 ddata->m4_state.reg,
520 					 ddata->m4_state.mask,
521 					 M4_STATE_OFF);
522 		if (err) {
523 			dev_err(&rproc->dev, "failed to set copro state\n");
524 			return err;
525 		}
526 	}
527 
528 	return 0;
529 }
530 
531 static void stm32_rproc_kick(struct rproc *rproc, int vqid)
532 {
533 	struct stm32_rproc *ddata = rproc->priv;
534 	unsigned int i;
535 	int err;
536 
537 	if (WARN_ON(vqid >= MBOX_NB_VQ))
538 		return;
539 
540 	for (i = 0; i < MBOX_NB_MBX; i++) {
541 		if (vqid != ddata->mb[i].vq_id)
542 			continue;
543 		if (!ddata->mb[i].chan)
544 			return;
545 		err = mbox_send_message(ddata->mb[i].chan, "kick");
546 		if (err < 0)
547 			dev_err(&rproc->dev, "%s: failed (%s, err:%d)\n",
548 				__func__, ddata->mb[i].name, err);
549 		return;
550 	}
551 }
552 
553 static int stm32_rproc_da_to_pa(struct rproc *rproc,
554 				u64 da, phys_addr_t *pa)
555 {
556 	struct stm32_rproc *ddata = rproc->priv;
557 	struct device *dev = rproc->dev.parent;
558 	struct stm32_rproc_mem *p_mem;
559 	unsigned int i;
560 
561 	for (i = 0; i < ddata->nb_rmems; i++) {
562 		p_mem = &ddata->rmems[i];
563 
564 		if (da < p_mem->dev_addr ||
565 		    da >= p_mem->dev_addr + p_mem->size)
566 			continue;
567 
568 		*pa = da - p_mem->dev_addr + p_mem->bus_addr;
569 		dev_dbg(dev, "da %llx to pa %pap\n", da, pa);
570 
571 		return 0;
572 	}
573 
574 	dev_err(dev, "can't translate da %llx\n", da);
575 
576 	return -EINVAL;
577 }
578 
579 static struct resource_table *
580 stm32_rproc_get_loaded_rsc_table(struct rproc *rproc, size_t *table_sz)
581 {
582 	struct stm32_rproc *ddata = rproc->priv;
583 	struct device *dev = rproc->dev.parent;
584 	phys_addr_t rsc_pa;
585 	u32 rsc_da;
586 	int err;
587 
588 	/* The resource table has already been mapped, nothing to do */
589 	if (ddata->rsc_va)
590 		goto done;
591 
592 	err = regmap_read(ddata->rsctbl.map, ddata->rsctbl.reg, &rsc_da);
593 	if (err) {
594 		dev_err(dev, "failed to read rsc tbl addr\n");
595 		return ERR_PTR(-EINVAL);
596 	}
597 
598 	if (!rsc_da)
599 		/* no rsc table */
600 		return ERR_PTR(-ENOENT);
601 
602 	err = stm32_rproc_da_to_pa(rproc, rsc_da, &rsc_pa);
603 	if (err)
604 		return ERR_PTR(err);
605 
606 	ddata->rsc_va = devm_ioremap_wc(dev, rsc_pa, RSC_TBL_SIZE);
607 	if (IS_ERR_OR_NULL(ddata->rsc_va)) {
608 		dev_err(dev, "Unable to map memory region: %pa+%x\n",
609 			&rsc_pa, RSC_TBL_SIZE);
610 		ddata->rsc_va = NULL;
611 		return ERR_PTR(-ENOMEM);
612 	}
613 
614 done:
615 	/*
616 	 * Assuming the resource table fits in 1kB is fair.
617 	 * Notice for the detach, that this 1 kB memory area has to be reserved in the coprocessor
618 	 * firmware for the resource table. On detach, the remoteproc core re-initializes this
619 	 * entire area by overwriting it with the initial values stored in rproc->clean_table.
620 	 */
621 	*table_sz = RSC_TBL_SIZE;
622 	return (__force struct resource_table *)ddata->rsc_va;
623 }
624 
625 static const struct rproc_ops st_rproc_ops = {
626 	.prepare	= stm32_rproc_prepare,
627 	.start		= stm32_rproc_start,
628 	.stop		= stm32_rproc_stop,
629 	.attach		= stm32_rproc_attach,
630 	.detach		= stm32_rproc_detach,
631 	.kick		= stm32_rproc_kick,
632 	.load		= rproc_elf_load_segments,
633 	.parse_fw	= stm32_rproc_parse_fw,
634 	.find_loaded_rsc_table = rproc_elf_find_loaded_rsc_table,
635 	.get_loaded_rsc_table = stm32_rproc_get_loaded_rsc_table,
636 	.sanity_check	= rproc_elf_sanity_check,
637 	.get_boot_addr	= rproc_elf_get_boot_addr,
638 };
639 
640 static const struct of_device_id stm32_rproc_match[] = {
641 	{ .compatible = "st,stm32mp1-m4" },
642 	{},
643 };
644 MODULE_DEVICE_TABLE(of, stm32_rproc_match);
645 
646 static int stm32_rproc_get_syscon(struct device_node *np, const char *prop,
647 				  struct stm32_syscon *syscon)
648 {
649 	int err = 0;
650 
651 	syscon->map = syscon_regmap_lookup_by_phandle(np, prop);
652 	if (IS_ERR(syscon->map)) {
653 		err = PTR_ERR(syscon->map);
654 		syscon->map = NULL;
655 		goto out;
656 	}
657 
658 	err = of_property_read_u32_index(np, prop, 1, &syscon->reg);
659 	if (err)
660 		goto out;
661 
662 	err = of_property_read_u32_index(np, prop, 2, &syscon->mask);
663 
664 out:
665 	return err;
666 }
667 
668 static int stm32_rproc_parse_dt(struct platform_device *pdev,
669 				struct stm32_rproc *ddata, bool *auto_boot)
670 {
671 	struct device *dev = &pdev->dev;
672 	struct device_node *np = dev->of_node;
673 	struct stm32_syscon tz;
674 	unsigned int tzen;
675 	int err, irq;
676 
677 	irq = platform_get_irq_optional(pdev, 0);
678 	if (irq == -EPROBE_DEFER)
679 		return irq;
680 
681 	if (irq > 0) {
682 		err = devm_request_irq(dev, irq, stm32_rproc_wdg, 0,
683 				       dev_name(dev), pdev);
684 		if (err)
685 			return err;
686 
687 		ddata->wdg_irq = irq;
688 
689 		if (of_property_read_bool(np, "wakeup-source")) {
690 			device_init_wakeup(dev, true);
691 			dev_pm_set_wake_irq(dev, irq);
692 		}
693 
694 		dev_info(dev, "wdg irq registered\n");
695 	}
696 
697 	ddata->rst = devm_reset_control_get_optional(dev, "mcu_rst");
698 	if (!ddata->rst) {
699 		/* Try legacy fallback method: get it by index */
700 		ddata->rst = devm_reset_control_get_by_index(dev, 0);
701 	}
702 	if (IS_ERR(ddata->rst))
703 		return dev_err_probe(dev, PTR_ERR(ddata->rst),
704 				     "failed to get mcu_reset\n");
705 
706 	/*
707 	 * Three ways to manage the hold boot
708 	 * - using SCMI: the hold boot is managed as a reset
709 	 *    The DT "reset-mames" property should be defined with 2 items:
710 	 *        reset-names = "mcu_rst", "hold_boot";
711 	 * - using SMC call (deprecated): use SMC reset interface
712 	 *    The DT "reset-mames" property is optional, "st,syscfg-tz" is required
713 	 * - default(no SCMI, no SMC): the hold boot is managed as a syscon register
714 	 *    The DT "reset-mames" property is optional, "st,syscfg-holdboot" is required
715 	 */
716 
717 	ddata->hold_boot_rst = devm_reset_control_get_optional(dev, "hold_boot");
718 	if (IS_ERR(ddata->hold_boot_rst))
719 		return dev_err_probe(dev, PTR_ERR(ddata->hold_boot_rst),
720 				     "failed to get hold_boot reset\n");
721 
722 	if (!ddata->hold_boot_rst && IS_ENABLED(CONFIG_HAVE_ARM_SMCCC)) {
723 		/* Manage the MCU_BOOT using SMC call */
724 		err = stm32_rproc_get_syscon(np, "st,syscfg-tz", &tz);
725 		if (!err) {
726 			err = regmap_read(tz.map, tz.reg, &tzen);
727 			if (err) {
728 				dev_err(dev, "failed to read tzen\n");
729 				return err;
730 			}
731 			ddata->hold_boot_smc = tzen & tz.mask;
732 		}
733 	}
734 
735 	if (!ddata->hold_boot_rst && !ddata->hold_boot_smc) {
736 		/* Default: hold boot manage it through the syscon controller */
737 		err = stm32_rproc_get_syscon(np, "st,syscfg-holdboot",
738 					     &ddata->hold_boot);
739 		if (err) {
740 			dev_err(dev, "failed to get hold boot\n");
741 			return err;
742 		}
743 	}
744 
745 	err = stm32_rproc_get_syscon(np, "st,syscfg-pdds", &ddata->pdds);
746 	if (err)
747 		dev_info(dev, "failed to get pdds\n");
748 
749 	*auto_boot = of_property_read_bool(np, "st,auto-boot");
750 
751 	/*
752 	 * See if we can check the M4 status, i.e if it was started
753 	 * from the boot loader or not.
754 	 */
755 	err = stm32_rproc_get_syscon(np, "st,syscfg-m4-state",
756 				     &ddata->m4_state);
757 	if (err) {
758 		/* remember this */
759 		ddata->m4_state.map = NULL;
760 		/* no coprocessor state syscon (optional) */
761 		dev_warn(dev, "m4 state not supported\n");
762 
763 		/* no need to go further */
764 		return 0;
765 	}
766 
767 	/* See if we can get the resource table */
768 	err = stm32_rproc_get_syscon(np, "st,syscfg-rsc-tbl",
769 				     &ddata->rsctbl);
770 	if (err) {
771 		/* no rsc table syscon (optional) */
772 		dev_warn(dev, "rsc tbl syscon not supported\n");
773 	}
774 
775 	return 0;
776 }
777 
778 static int stm32_rproc_get_m4_status(struct stm32_rproc *ddata,
779 				     unsigned int *state)
780 {
781 	/* See stm32_rproc_parse_dt() */
782 	if (!ddata->m4_state.map) {
783 		/*
784 		 * We couldn't get the coprocessor's state, assume
785 		 * it is not running.
786 		 */
787 		*state = M4_STATE_OFF;
788 		return 0;
789 	}
790 
791 	return regmap_read(ddata->m4_state.map, ddata->m4_state.reg, state);
792 }
793 
794 static int stm32_rproc_probe(struct platform_device *pdev)
795 {
796 	struct device *dev = &pdev->dev;
797 	struct stm32_rproc *ddata;
798 	struct device_node *np = dev->of_node;
799 	const char *fw_name;
800 	struct rproc *rproc;
801 	unsigned int state;
802 	int ret;
803 
804 	ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
805 	if (ret)
806 		return ret;
807 
808 	/* Look for an optional firmware name */
809 	ret = rproc_of_parse_firmware(dev, 0, &fw_name);
810 	if (ret < 0 && ret != -EINVAL)
811 		return ret;
812 
813 	rproc = devm_rproc_alloc(dev, np->name, &st_rproc_ops, fw_name, sizeof(*ddata));
814 	if (!rproc)
815 		return -ENOMEM;
816 
817 	ddata = rproc->priv;
818 
819 	rproc_coredump_set_elf_info(rproc, ELFCLASS32, EM_NONE);
820 
821 	ret = stm32_rproc_parse_dt(pdev, ddata, &rproc->auto_boot);
822 	if (ret)
823 		goto free_rproc;
824 
825 	ret = stm32_rproc_of_memory_translations(pdev, ddata);
826 	if (ret)
827 		goto free_rproc;
828 
829 	ret = stm32_rproc_get_m4_status(ddata, &state);
830 	if (ret)
831 		goto free_rproc;
832 
833 	if (state == M4_STATE_CRUN)
834 		rproc->state = RPROC_DETACHED;
835 
836 	rproc->has_iommu = false;
837 	ddata->workqueue = create_workqueue(dev_name(dev));
838 	if (!ddata->workqueue) {
839 		dev_err(dev, "cannot create workqueue\n");
840 		ret = -ENOMEM;
841 		goto free_resources;
842 	}
843 
844 	platform_set_drvdata(pdev, rproc);
845 
846 	ret = stm32_rproc_request_mbox(rproc);
847 	if (ret)
848 		goto free_wkq;
849 
850 	ret = rproc_add(rproc);
851 	if (ret)
852 		goto free_mb;
853 
854 	return 0;
855 
856 free_mb:
857 	stm32_rproc_free_mbox(rproc);
858 free_wkq:
859 	destroy_workqueue(ddata->workqueue);
860 free_resources:
861 	rproc_resource_cleanup(rproc);
862 free_rproc:
863 	if (device_may_wakeup(dev)) {
864 		dev_pm_clear_wake_irq(dev);
865 		device_init_wakeup(dev, false);
866 	}
867 	return ret;
868 }
869 
870 static void 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 }
888 
889 static int stm32_rproc_suspend(struct device *dev)
890 {
891 	struct rproc *rproc = dev_get_drvdata(dev);
892 	struct stm32_rproc *ddata = rproc->priv;
893 
894 	if (device_may_wakeup(dev))
895 		return enable_irq_wake(ddata->wdg_irq);
896 
897 	return 0;
898 }
899 
900 static int stm32_rproc_resume(struct device *dev)
901 {
902 	struct rproc *rproc = dev_get_drvdata(dev);
903 	struct stm32_rproc *ddata = rproc->priv;
904 
905 	if (device_may_wakeup(dev))
906 		return disable_irq_wake(ddata->wdg_irq);
907 
908 	return 0;
909 }
910 
911 static DEFINE_SIMPLE_DEV_PM_OPS(stm32_rproc_pm_ops,
912 				stm32_rproc_suspend, stm32_rproc_resume);
913 
914 static struct platform_driver stm32_rproc_driver = {
915 	.probe = stm32_rproc_probe,
916 	.remove = stm32_rproc_remove,
917 	.driver = {
918 		.name = "stm32-rproc",
919 		.pm = pm_ptr(&stm32_rproc_pm_ops),
920 		.of_match_table = stm32_rproc_match,
921 	},
922 };
923 module_platform_driver(stm32_rproc_driver);
924 
925 MODULE_DESCRIPTION("STM32 Remote Processor Control Driver");
926 MODULE_AUTHOR("Ludovic Barre <ludovic.barre@st.com>");
927 MODULE_AUTHOR("Fabien Dessenne <fabien.dessenne@st.com>");
928 MODULE_LICENSE("GPL v2");
929