1 // SPDX-License-Identifier: GPL-2.0-only
4  * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
25  * of a single 32-bit value between two processors.  Each value has a single
26  * writer (the local side) and a single reader (the remote side). Values are
28  * to remote processor ID) and a string identifier.
31  * item is writable by the local processor and readable by the remote
32  * processor.  By using two separate SMEM items that are single-reader and
33  * single-writer, SMP2P does not require any remote locking mechanisms.
51  * struct smp2p_smem_item - in memory communication structure
53  * @version:		version - must be 1
54  * @features:		features flag - currently unused
57  * @total_entries:	number of entries - always SMP2P_MAX_ENTRY
81  * struct smp2p_entry - driver context matching one entry
92  * @lock:	spinlock to protect read-modify-write of the value
116  * struct qcom_smp2p - device driver context
129  * @ipc_bit:	bit in regmap@offset to kick to signal remote processor
168 	if (smp2p->mbox_chan) {  in qcom_smp2p_kick()
169 		mbox_send_message(smp2p->mbox_chan, NULL);  in qcom_smp2p_kick()
170 		mbox_client_txdone(smp2p->mbox_chan, 0);  in qcom_smp2p_kick()
172 		regmap_write(smp2p->ipc_regmap, smp2p->ipc_offset, BIT(smp2p->ipc_bit));  in qcom_smp2p_kick()
178 	struct smp2p_smem_item *in = smp2p->in;  in qcom_smp2p_check_ssr()
181 	if (!smp2p->ssr_ack_enabled)  in qcom_smp2p_check_ssr()
184 	restart = in->flags & BIT(SMP2P_FLAGS_RESTART_DONE_BIT);  in qcom_smp2p_check_ssr()
186 	return restart != smp2p->ssr_ack;  in qcom_smp2p_check_ssr()
191 	struct smp2p_smem_item *out = smp2p->out;  in qcom_smp2p_do_ssr_ack()
194 	smp2p->ssr_ack = !smp2p->ssr_ack;  in qcom_smp2p_do_ssr_ack()
196 	val = out->flags & ~BIT(SMP2P_FLAGS_RESTART_ACK_BIT);  in qcom_smp2p_do_ssr_ack()
197 	if (smp2p->ssr_ack)  in qcom_smp2p_do_ssr_ack()
199 	out->flags = val;  in qcom_smp2p_do_ssr_ack()
206 	struct smp2p_smem_item *out = smp2p->out;  in qcom_smp2p_negotiate()
207 	struct smp2p_smem_item *in = smp2p->in;  in qcom_smp2p_negotiate()
209 	if (in->version == out->version) {  in qcom_smp2p_negotiate()
210 		out->features &= in->features;  in qcom_smp2p_negotiate()
212 		if (out->features & SMP2P_FEATURE_SSR_ACK)  in qcom_smp2p_negotiate()
213 			smp2p->ssr_ack_enabled = true;  in qcom_smp2p_negotiate()
215 		smp2p->negotiation_done = true;  in qcom_smp2p_negotiate()
229 	in = smp2p->in;  in qcom_smp2p_notify_in()
232 	for (i = smp2p->valid_entries; i < in->valid_entries; i++) {  in qcom_smp2p_notify_in()
233 		list_for_each_entry(entry, &smp2p->inbound, node) {  in qcom_smp2p_notify_in()
234 			memcpy(buf, in->entries[i].name, sizeof(buf));  in qcom_smp2p_notify_in()
235 			if (!strcmp(buf, entry->name)) {  in qcom_smp2p_notify_in()
236 				entry->value = &in->entries[i].value;  in qcom_smp2p_notify_in()
241 	smp2p->valid_entries = i;  in qcom_smp2p_notify_in()
244 	list_for_each_entry(entry, &smp2p->inbound, node) {  in qcom_smp2p_notify_in()
245 		/* Ignore entries not yet allocated by the remote side */  in qcom_smp2p_notify_in()
246 		if (!entry->value)  in qcom_smp2p_notify_in()
249 		val = readl(entry->value);  in qcom_smp2p_notify_in()
251 		status = val ^ entry->last_value;  in qcom_smp2p_notify_in()
252 		entry->last_value = val;  in qcom_smp2p_notify_in()
258 		for_each_set_bit(i, entry->irq_enabled, 32) {  in qcom_smp2p_notify_in()
262 			if ((val & BIT(i) && test_bit(i, entry->irq_rising)) ||  in qcom_smp2p_notify_in()
263 			    (!(val & BIT(i)) && test_bit(i, entry->irq_falling))) {  in qcom_smp2p_notify_in()
264 				irq_pin = irq_find_mapping(entry->domain, i);  in qcom_smp2p_notify_in()
272  * qcom_smp2p_intr() - interrupt handler for incoming notifications
276  * Handle notifications from the remote side to handle newly allocated entries
283 	unsigned int smem_id = smp2p->smem_items[SMP2P_INBOUND];  in qcom_smp2p_intr()
284 	unsigned int pid = smp2p->remote_pid;  in qcom_smp2p_intr()  local
288 	in = smp2p->in;  in qcom_smp2p_intr()
292 		in = qcom_smem_get(pid, smem_id, &size);  in qcom_smp2p_intr()
294 			dev_err(smp2p->dev,  in qcom_smp2p_intr()
295 				"Unable to acquire remote smp2p item\n");  in qcom_smp2p_intr()
299 		smp2p->in = in;  in qcom_smp2p_intr()
302 	if (!smp2p->negotiation_done)  in qcom_smp2p_intr()
305 	if (smp2p->negotiation_done) {  in qcom_smp2p_intr()
322 	clear_bit(irq, entry->irq_enabled);  in smp2p_mask_irq()
330 	set_bit(irq, entry->irq_enabled);  in smp2p_unmask_irq()
339 		return -EINVAL;  in smp2p_set_irq_type()
342 		set_bit(irq, entry->irq_rising);  in smp2p_set_irq_type()
344 		clear_bit(irq, entry->irq_rising);  in smp2p_set_irq_type()
347 		set_bit(irq, entry->irq_falling);  in smp2p_set_irq_type()
349 		clear_bit(irq, entry->irq_falling);  in smp2p_set_irq_type()
365 	struct smp2p_entry *entry = d->host_data;  in smp2p_irq_map()
384 	entry->domain = irq_domain_add_linear(node, 32, &smp2p_irq_ops, entry);  in qcom_smp2p_inbound_entry()
385 	if (!entry->domain) {  in qcom_smp2p_inbound_entry()
386 		dev_err(smp2p->dev, "failed to add irq_domain\n");  in qcom_smp2p_inbound_entry()
387 		return -ENOMEM;  in qcom_smp2p_inbound_entry()
400 	spin_lock_irqsave(&entry->lock, flags);  in smp2p_update_bits()
401 	val = orig = readl(entry->value);  in smp2p_update_bits()
404 	writel(val, entry->value);  in smp2p_update_bits()
405 	spin_unlock_irqrestore(&entry->lock, flags);  in smp2p_update_bits()
408 		qcom_smp2p_kick(entry->smp2p);  in smp2p_update_bits()
421 	struct smp2p_smem_item *out = smp2p->out;  in qcom_smp2p_outbound_entry()
425 	strlcpy(buf, entry->name, SMP2P_MAX_ENTRY_NAME);  in qcom_smp2p_outbound_entry()
426 	memcpy(out->entries[out->valid_entries].name, buf, SMP2P_MAX_ENTRY_NAME);  in qcom_smp2p_outbound_entry()
429 	entry->value = &out->entries[out->valid_entries].value;  in qcom_smp2p_outbound_entry()
431 	out->valid_entries++;  in qcom_smp2p_outbound_entry()
433 	entry->state = qcom_smem_state_register(node, &smp2p_state_ops, entry);  in qcom_smp2p_outbound_entry()
434 	if (IS_ERR(entry->state)) {  in qcom_smp2p_outbound_entry()
435 		dev_err(smp2p->dev, "failed to register qcom_smem_state\n");  in qcom_smp2p_outbound_entry()
436 		return PTR_ERR(entry->state);  in qcom_smp2p_outbound_entry()
445 	unsigned smem_id = smp2p->smem_items[SMP2P_OUTBOUND];  in qcom_smp2p_alloc_outbound_item()
446 	unsigned pid = smp2p->remote_pid;  in qcom_smp2p_alloc_outbound_item()  local
449 	ret = qcom_smem_alloc(pid, smem_id, sizeof(*out));  in qcom_smp2p_alloc_outbound_item()
450 	if (ret < 0 && ret != -EEXIST) {  in qcom_smp2p_alloc_outbound_item()
451 		if (ret != -EPROBE_DEFER)  in qcom_smp2p_alloc_outbound_item()
452 			dev_err(smp2p->dev,  in qcom_smp2p_alloc_outbound_item()
457 	out = qcom_smem_get(pid, smem_id, NULL);  in qcom_smp2p_alloc_outbound_item()
459 		dev_err(smp2p->dev, "Unable to acquire local smp2p item\n");  in qcom_smp2p_alloc_outbound_item()
464 	out->magic = SMP2P_MAGIC;  in qcom_smp2p_alloc_outbound_item()
465 	out->local_pid = smp2p->local_pid;  in qcom_smp2p_alloc_outbound_item()
466 	out->remote_pid = smp2p->remote_pid;  in qcom_smp2p_alloc_outbound_item()
467 	out->total_entries = SMP2P_MAX_ENTRY;  in qcom_smp2p_alloc_outbound_item()
468 	out->valid_entries = 0;  in qcom_smp2p_alloc_outbound_item()
469 	out->features = SMP2P_ALL_FEATURES;  in qcom_smp2p_alloc_outbound_item()
476 	out->version = 1;  in qcom_smp2p_alloc_outbound_item()
480 	smp2p->out = out;  in qcom_smp2p_alloc_outbound_item()
488 	struct device *dev = smp2p->dev;  in smp2p_parse_ipc()
492 	syscon = of_parse_phandle(dev->of_node, "qcom,ipc", 0);  in smp2p_parse_ipc()
495 		return -ENODEV;  in smp2p_parse_ipc()
498 	smp2p->ipc_regmap = syscon_node_to_regmap(syscon);  in smp2p_parse_ipc()
500 	if (IS_ERR(smp2p->ipc_regmap))  in smp2p_parse_ipc()
501 		return PTR_ERR(smp2p->ipc_regmap);  in smp2p_parse_ipc()
504 	ret = of_property_read_u32_index(dev->of_node, key, 1, &smp2p->ipc_offset);  in smp2p_parse_ipc()
507 		return -EINVAL;  in smp2p_parse_ipc()
510 	ret = of_property_read_u32_index(dev->of_node, key, 2, &smp2p->ipc_bit);  in smp2p_parse_ipc()
513 		return -EINVAL;  in smp2p_parse_ipc()
528 	smp2p = devm_kzalloc(&pdev->dev, sizeof(*smp2p), GFP_KERNEL);  in qcom_smp2p_probe()
530 		return -ENOMEM;  in qcom_smp2p_probe()
532 	smp2p->dev = &pdev->dev;  in qcom_smp2p_probe()
533 	INIT_LIST_HEAD(&smp2p->inbound);  in qcom_smp2p_probe()
534 	INIT_LIST_HEAD(&smp2p->outbound);  in qcom_smp2p_probe()
539 	ret = of_property_read_u32_array(pdev->dev.of_node, key,  in qcom_smp2p_probe()
540 					 smp2p->smem_items, 2);  in qcom_smp2p_probe()
544 	key = "qcom,local-pid";  in qcom_smp2p_probe()
545 	ret = of_property_read_u32(pdev->dev.of_node, key, &smp2p->local_pid);  in qcom_smp2p_probe()
549 	key = "qcom,remote-pid";  in qcom_smp2p_probe()
550 	ret = of_property_read_u32(pdev->dev.of_node, key, &smp2p->remote_pid);  in qcom_smp2p_probe()
558 	smp2p->mbox_client.dev = &pdev->dev;  in qcom_smp2p_probe()
559 	smp2p->mbox_client.knows_txdone = true;  in qcom_smp2p_probe()
560 	smp2p->mbox_chan = mbox_request_channel(&smp2p->mbox_client, 0);  in qcom_smp2p_probe()
561 	if (IS_ERR(smp2p->mbox_chan)) {  in qcom_smp2p_probe()
562 		if (PTR_ERR(smp2p->mbox_chan) != -ENODEV)  in qcom_smp2p_probe()
563 			return PTR_ERR(smp2p->mbox_chan);  in qcom_smp2p_probe()
565 		smp2p->mbox_chan = NULL;  in qcom_smp2p_probe()
576 	for_each_available_child_of_node(pdev->dev.of_node, node) {  in qcom_smp2p_probe()
577 		entry = devm_kzalloc(&pdev->dev, sizeof(*entry), GFP_KERNEL);  in qcom_smp2p_probe()
579 			ret = -ENOMEM;  in qcom_smp2p_probe()
584 		entry->smp2p = smp2p;  in qcom_smp2p_probe()
585 		spin_lock_init(&entry->lock);  in qcom_smp2p_probe()
587 		ret = of_property_read_string(node, "qcom,entry-name", &entry->name);  in qcom_smp2p_probe()
593 		if (of_property_read_bool(node, "interrupt-controller")) {  in qcom_smp2p_probe()
600 			list_add(&entry->node, &smp2p->inbound);  in qcom_smp2p_probe()
608 			list_add(&entry->node, &smp2p->outbound);  in qcom_smp2p_probe()
615 	ret = devm_request_threaded_irq(&pdev->dev, irq,  in qcom_smp2p_probe()
620 		dev_err(&pdev->dev, "failed to request interrupt\n");  in qcom_smp2p_probe()
633 	device_set_wakeup_capable(&pdev->dev, true);  in qcom_smp2p_probe()
635 	ret = dev_pm_set_wake_irq(&pdev->dev, irq);  in qcom_smp2p_probe()
642 	dev_pm_clear_wake_irq(&pdev->dev);  in qcom_smp2p_probe()
645 	list_for_each_entry(entry, &smp2p->inbound, node)  in qcom_smp2p_probe()
646 		irq_domain_remove(entry->domain);  in qcom_smp2p_probe()
648 	list_for_each_entry(entry, &smp2p->outbound, node)  in qcom_smp2p_probe()
649 		qcom_smem_state_unregister(entry->state);  in qcom_smp2p_probe()
651 	smp2p->out->valid_entries = 0;  in qcom_smp2p_probe()
654 	mbox_free_channel(smp2p->mbox_chan);  in qcom_smp2p_probe()
659 	dev_err(&pdev->dev, "failed to read %s\n", key);  in qcom_smp2p_probe()
660 	return -EINVAL;  in qcom_smp2p_probe()
668 	dev_pm_clear_wake_irq(&pdev->dev);  in qcom_smp2p_remove()
670 	list_for_each_entry(entry, &smp2p->inbound, node)  in qcom_smp2p_remove()
671 		irq_domain_remove(entry->domain);  in qcom_smp2p_remove()
673 	list_for_each_entry(entry, &smp2p->outbound, node)  in qcom_smp2p_remove()
674 		qcom_smem_state_unregister(entry->state);  in qcom_smp2p_remove()
676 	mbox_free_channel(smp2p->mbox_chan);  in qcom_smp2p_remove()
678 	smp2p->out->valid_entries = 0;  in qcom_smp2p_remove()