1 // SPDX-License-Identifier: GPL-2.0-only
4  * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
7 #include <linux/interrupt.h>
19  * This driver implements the Qualcomm Shared Memory State Machine, a mechanism
22  * The implementation is based on two sections of shared memory; the first
27  * read-write, while the rest should be considered read-only.
34  * The subscription matrix is laid out in entry-major order:
40  * A third, optional, shared memory region might contain information regarding
46  * Shared memory identifiers, used to acquire handles to respective memory
63  * struct qcom_smsm - smsm driver context
72  * @lock:	spinlock for read-modify-write of the outgoing state
98  * struct smsm_entry - per remote processor entry context
99  * @smsm:	back-reference to driver context
123  * struct smsm_host - representation of a remote host
124  * @ipc_regmap:	regmap for outgoing interrupt
125  * @ipc_offset:	offset in @ipc_regmap for outgoing interrupt
126  * @ipc_bit:	bit in @ipc_regmap + @ipc_offset for outgoing interrupt
138  * smsm_update_bits() - change bit in outgoing entry and inform subscribers
156 	spin_lock_irqsave(&smsm->lock, flags);  in smsm_update_bits()
159 	val = orig = readl(smsm->local_state);  in smsm_update_bits()
166 		spin_unlock_irqrestore(&smsm->lock, flags);  in smsm_update_bits()
171 	writel(val, smsm->local_state);  in smsm_update_bits()
172 	spin_unlock_irqrestore(&smsm->lock, flags);  in smsm_update_bits()
178 	for (host = 0; host < smsm->num_hosts; host++) {  in smsm_update_bits()
179 		hostp = &smsm->hosts[host];  in smsm_update_bits()
181 		val = readl(smsm->subscription + host);  in smsm_update_bits()
185 		if (hostp->mbox_chan) {  in smsm_update_bits()
186 			mbox_send_message(hostp->mbox_chan, NULL);  in smsm_update_bits()
187 			mbox_client_txdone(hostp->mbox_chan, 0);  in smsm_update_bits()
188 		} else if (hostp->ipc_regmap) {  in smsm_update_bits()
189 			regmap_write(hostp->ipc_regmap,  in smsm_update_bits()
190 				     hostp->ipc_offset,  in smsm_update_bits()
191 				     BIT(hostp->ipc_bit));  in smsm_update_bits()
204  * smsm_intr() - cascading IRQ handler for SMSM
208  * This function cascades an incoming interrupt from a remote system, based on
219 	val = readl(entry->remote_state);  in smsm_intr()
220 	changed = val ^ xchg(&entry->last_value, val);  in smsm_intr()
222 	for_each_set_bit(i, entry->irq_enabled, 32) {  in smsm_intr()
227 			if (test_bit(i, entry->irq_rising)) {  in smsm_intr()
228 				irq_pin = irq_find_mapping(entry->domain, i);  in smsm_intr()
232 			if (test_bit(i, entry->irq_falling)) {  in smsm_intr()
233 				irq_pin = irq_find_mapping(entry->domain, i);  in smsm_intr()
243  * smsm_mask_irq() - un-subscribe from cascades of IRQs of a certain staus bit
246  * This un-subscribes the local CPU from interrupts upon changes to the defines
253 	struct qcom_smsm *smsm = entry->smsm;  in smsm_mask_irq()
256 	if (entry->subscription) {  in smsm_mask_irq()
257 		val = readl(entry->subscription + smsm->local_host);  in smsm_mask_irq()
259 		writel(val, entry->subscription + smsm->local_host);  in smsm_mask_irq()
262 	clear_bit(irq, entry->irq_enabled);  in smsm_mask_irq()
266  * smsm_unmask_irq() - subscribe to cascades of IRQs of a certain status bit
276 	struct qcom_smsm *smsm = entry->smsm;  in smsm_unmask_irq()
279 	/* Make sure our last cached state is up-to-date */  in smsm_unmask_irq()
280 	if (readl(entry->remote_state) & BIT(irq))  in smsm_unmask_irq()
281 		set_bit(irq, &entry->last_value);  in smsm_unmask_irq()
283 		clear_bit(irq, &entry->last_value);  in smsm_unmask_irq()
285 	set_bit(irq, entry->irq_enabled);  in smsm_unmask_irq()
287 	if (entry->subscription) {  in smsm_unmask_irq()
288 		val = readl(entry->subscription + smsm->local_host);  in smsm_unmask_irq()
290 		writel(val, entry->subscription + smsm->local_host);  in smsm_unmask_irq()
295  * smsm_set_irq_type() - updates the requested IRQ type for the cascading
296  * @irqd:	consumer interrupt handle
305 		return -EINVAL;  in smsm_set_irq_type()
308 		set_bit(irq, entry->irq_rising);  in smsm_set_irq_type()
310 		clear_bit(irq, entry->irq_rising);  in smsm_set_irq_type()
313 		set_bit(irq, entry->irq_falling);  in smsm_set_irq_type()
315 		clear_bit(irq, entry->irq_falling);  in smsm_set_irq_type()
328 		return -EINVAL;  in smsm_get_irqchip_state()
330 	val = readl(entry->remote_state);  in smsm_get_irqchip_state()
345  * smsm_irq_map() - sets up a mapping for a cascaded IRQ
354 	struct smsm_entry *entry = d->host_data;  in smsm_irq_map()
369  * smsm_parse_mbox() - requests an mbox channel
374  * sending the outgoing interrupts to a remove hosts - identified by @host_id.
378 	struct smsm_host *host = &smsm->hosts[host_id];  in smsm_parse_mbox()
381 	host->mbox_chan = mbox_request_channel(&smsm->mbox_client, host_id);  in smsm_parse_mbox()
382 	if (IS_ERR(host->mbox_chan)) {  in smsm_parse_mbox()
383 		ret = PTR_ERR(host->mbox_chan);  in smsm_parse_mbox()
384 		host->mbox_chan = NULL;  in smsm_parse_mbox()
391  * smsm_parse_ipc() - parses a qcom,ipc-%d device tree property
396  * outgoing interrupts to a remote host - identified by @host_id.
401 	struct device_node *node = smsm->dev->of_node;  in smsm_parse_ipc()
402 	struct smsm_host *host = &smsm->hosts[host_id];  in smsm_parse_ipc()
406 	snprintf(key, sizeof(key), "qcom,ipc-%d", host_id);  in smsm_parse_ipc()
411 	host->ipc_regmap = syscon_node_to_regmap(syscon);  in smsm_parse_ipc()
413 	if (IS_ERR(host->ipc_regmap))  in smsm_parse_ipc()
414 		return PTR_ERR(host->ipc_regmap);  in smsm_parse_ipc()
416 	ret = of_property_read_u32_index(node, key, 1, &host->ipc_offset);  in smsm_parse_ipc()
418 		dev_err(smsm->dev, "no offset in %s\n", key);  in smsm_parse_ipc()
419 		return -EINVAL;  in smsm_parse_ipc()
422 	ret = of_property_read_u32_index(node, key, 2, &host->ipc_bit);  in smsm_parse_ipc()
424 		dev_err(smsm->dev, "no bit in %s\n", key);  in smsm_parse_ipc()
425 		return -EINVAL;  in smsm_parse_ipc()
432  * smsm_inbound_entry() - parse DT and set up an entry representing a remote system
446 		dev_err(smsm->dev, "failed to parse smsm interrupt\n");  in smsm_inbound_entry()
447 		return -EINVAL;  in smsm_inbound_entry()
450 	ret = devm_request_threaded_irq(smsm->dev, irq,  in smsm_inbound_entry()
455 		dev_err(smsm->dev, "failed to request interrupt\n");  in smsm_inbound_entry()
459 	entry->domain = irq_domain_add_linear(node, 32, &smsm_irq_ops, entry);  in smsm_inbound_entry()
460 	if (!entry->domain) {  in smsm_inbound_entry()
461 		dev_err(smsm->dev, "failed to add irq_domain\n");  in smsm_inbound_entry()
462 		return -ENOMEM;  in smsm_inbound_entry()
469  * smsm_get_size_info() - parse the optional memory segment for sizes
472  * Attempt to acquire the number of hosts and entries from the optional shared
490 	if (IS_ERR(info) && PTR_ERR(info) != -ENOENT)  in smsm_get_size_info()
491 		return dev_err_probe(smsm->dev, PTR_ERR(info),  in smsm_get_size_info()
494 		dev_warn(smsm->dev, "no smsm size info, using defaults\n");  in smsm_get_size_info()
495 		smsm->num_entries = SMSM_DEFAULT_NUM_ENTRIES;  in smsm_get_size_info()
496 		smsm->num_hosts = SMSM_DEFAULT_NUM_HOSTS;  in smsm_get_size_info()
500 	smsm->num_entries = info->num_entries;  in smsm_get_size_info()
501 	smsm->num_hosts = info->num_hosts;  in smsm_get_size_info()
503 	dev_dbg(smsm->dev,  in smsm_get_size_info()
505 		smsm->num_entries, smsm->num_hosts);  in smsm_get_size_info()
522 	smsm = devm_kzalloc(&pdev->dev, sizeof(*smsm), GFP_KERNEL);  in qcom_smsm_probe()
524 		return -ENOMEM;  in qcom_smsm_probe()
525 	smsm->dev = &pdev->dev;  in qcom_smsm_probe()
526 	spin_lock_init(&smsm->lock);  in qcom_smsm_probe()
532 	smsm->entries = devm_kcalloc(&pdev->dev,  in qcom_smsm_probe()
533 				     smsm->num_entries,  in qcom_smsm_probe()
536 	if (!smsm->entries)  in qcom_smsm_probe()
537 		return -ENOMEM;  in qcom_smsm_probe()
539 	smsm->hosts = devm_kcalloc(&pdev->dev,  in qcom_smsm_probe()
540 				   smsm->num_hosts,  in qcom_smsm_probe()
543 	if (!smsm->hosts)  in qcom_smsm_probe()
544 		return -ENOMEM;  in qcom_smsm_probe()
546 	for_each_child_of_node(pdev->dev.of_node, local_node) {  in qcom_smsm_probe()
547 		if (of_property_present(local_node, "#qcom,smem-state-cells"))  in qcom_smsm_probe()
551 		dev_err(&pdev->dev, "no state entry\n");  in qcom_smsm_probe()
552 		return -EINVAL;  in qcom_smsm_probe()
555 	of_property_read_u32(pdev->dev.of_node,  in qcom_smsm_probe()
556 			     "qcom,local-host",  in qcom_smsm_probe()
557 			     &smsm->local_host);  in qcom_smsm_probe()
559 	smsm->mbox_client.dev = &pdev->dev;  in qcom_smsm_probe()
560 	smsm->mbox_client.knows_txdone = true;  in qcom_smsm_probe()
563 	for (id = 0; id < smsm->num_hosts; id++) {  in qcom_smsm_probe()
576 			      smsm->num_entries * sizeof(u32));  in qcom_smsm_probe()
577 	if (ret < 0 && ret != -EEXIST) {  in qcom_smsm_probe()
578 		dev_err(&pdev->dev, "unable to allocate shared state entry\n");  in qcom_smsm_probe()
584 		dev_err(&pdev->dev, "Unable to acquire shared state entry\n");  in qcom_smsm_probe()
589 	/* Acquire the list of interrupt mask vectors */  in qcom_smsm_probe()
590 	size = smsm->num_entries * smsm->num_hosts * sizeof(u32);  in qcom_smsm_probe()
592 	if (ret < 0 && ret != -EEXIST) {  in qcom_smsm_probe()
593 		dev_err(&pdev->dev, "unable to allocate smsm interrupt mask\n");  in qcom_smsm_probe()
599 		dev_err(&pdev->dev, "unable to acquire shared memory interrupt mask\n");  in qcom_smsm_probe()
605 	smsm->local_state = states + smsm->local_host;  in qcom_smsm_probe()
606 	smsm->subscription = intr_mask + smsm->local_host * smsm->num_hosts;  in qcom_smsm_probe()
609 	smsm->state = qcom_smem_state_register(local_node, &smsm_state_ops, smsm);  in qcom_smsm_probe()
610 	if (IS_ERR(smsm->state)) {  in qcom_smsm_probe()
611 		dev_err(smsm->dev, "failed to register qcom_smem_state\n");  in qcom_smsm_probe()
612 		ret = PTR_ERR(smsm->state);  in qcom_smsm_probe()
617 	for_each_available_child_of_node(pdev->dev.of_node, node) {  in qcom_smsm_probe()
618 		if (!of_property_read_bool(node, "interrupt-controller"))  in qcom_smsm_probe()
622 		if (ret || id >= smsm->num_entries) {  in qcom_smsm_probe()
623 			dev_err(&pdev->dev, "invalid reg of entry\n");  in qcom_smsm_probe()
625 				ret = -EINVAL;  in qcom_smsm_probe()
628 		entry = &smsm->entries[id];  in qcom_smsm_probe()
630 		entry->smsm = smsm;  in qcom_smsm_probe()
631 		entry->remote_state = states + id;  in qcom_smsm_probe()
634 		entry->subscription = intr_mask + id * smsm->num_hosts;  in qcom_smsm_probe()
635 		writel(0, entry->subscription + smsm->local_host);  in qcom_smsm_probe()
649 	for (id = 0; id < smsm->num_entries; id++)  in qcom_smsm_probe()
650 		if (smsm->entries[id].domain)  in qcom_smsm_probe()
651 			irq_domain_remove(smsm->entries[id].domain);  in qcom_smsm_probe()
653 	qcom_smem_state_unregister(smsm->state);  in qcom_smsm_probe()
655 	for (id = 0; id < smsm->num_hosts; id++)  in qcom_smsm_probe()
656 		mbox_free_channel(smsm->hosts[id].mbox_chan);  in qcom_smsm_probe()
667 	for (id = 0; id < smsm->num_entries; id++)  in qcom_smsm_remove()
668 		if (smsm->entries[id].domain)  in qcom_smsm_remove()
669 			irq_domain_remove(smsm->entries[id].domain);  in qcom_smsm_remove()
671 	for (id = 0; id < smsm->num_hosts; id++)  in qcom_smsm_remove()
672 		mbox_free_channel(smsm->hosts[id].mbox_chan);  in qcom_smsm_remove()
674 	qcom_smem_state_unregister(smsm->state);  in qcom_smsm_remove()
687 		.name  = "qcom-smsm",
693 MODULE_DESCRIPTION("Qualcomm Shared Memory State Machine driver");