1 // SPDX-License-Identifier: GPL-2.0-only
4  * Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
7 #include <linux/interrupt.h>
18  * This driver implements the Qualcomm Shared Memory State Machine, a mechanism
21  * The implementation is based on two sections of shared memory; the first
26  * read-write, while the rest should be considered read-only.
33  * The subscription matrix is laid out in entry-major order:
39  * A third, optional, shared memory region might contain information regarding
45  * Shared memory identifiers, used to acquire handles to respective memory
62  * struct qcom_smsm - smsm driver context
71  * @lock:	spinlock for read-modify-write of the outgoing state
94  * struct smsm_entry - per remote processor entry context
95  * @smsm:	back-reference to driver context
119  * struct smsm_host - representation of a remote host
120  * @ipc_regmap:	regmap for outgoing interrupt
121  * @ipc_offset:	offset in @ipc_regmap for outgoing interrupt
122  * @ipc_bit:	bit in @ipc_regmap + @ipc_offset for outgoing interrupt
131  * smsm_update_bits() - change bit in outgoing entry and inform subscribers
149 	spin_lock_irqsave(&smsm->lock, flags);  in smsm_update_bits()
152 	val = orig = readl(smsm->local_state);  in smsm_update_bits()
159 		spin_unlock_irqrestore(&smsm->lock, flags);  in smsm_update_bits()
164 	writel(val, smsm->local_state);  in smsm_update_bits()
165 	spin_unlock_irqrestore(&smsm->lock, flags);  in smsm_update_bits()
171 	for (host = 0; host < smsm->num_hosts; host++) {  in smsm_update_bits()
172 		hostp = &smsm->hosts[host];  in smsm_update_bits()
174 		val = readl(smsm->subscription + host);  in smsm_update_bits()
175 		if (val & changes && hostp->ipc_regmap) {  in smsm_update_bits()
176 			regmap_write(hostp->ipc_regmap,  in smsm_update_bits()
177 				     hostp->ipc_offset,  in smsm_update_bits()
178 				     BIT(hostp->ipc_bit));  in smsm_update_bits()
191  * smsm_intr() - cascading IRQ handler for SMSM
195  * This function cascades an incoming interrupt from a remote system, based on
206 	val = readl(entry->remote_state);  in smsm_intr()
207 	changed = val ^ xchg(&entry->last_value, val);  in smsm_intr()
209 	for_each_set_bit(i, entry->irq_enabled, 32) {  in smsm_intr()
214 			if (test_bit(i, entry->irq_rising)) {  in smsm_intr()
215 				irq_pin = irq_find_mapping(entry->domain, i);  in smsm_intr()
219 			if (test_bit(i, entry->irq_falling)) {  in smsm_intr()
220 				irq_pin = irq_find_mapping(entry->domain, i);  in smsm_intr()
230  * smsm_mask_irq() - un-subscribe from cascades of IRQs of a certain staus bit
233  * This un-subscribes the local CPU from interrupts upon changes to the defines
240 	struct qcom_smsm *smsm = entry->smsm;  in smsm_mask_irq()
243 	if (entry->subscription) {  in smsm_mask_irq()
244 		val = readl(entry->subscription + smsm->local_host);  in smsm_mask_irq()
246 		writel(val, entry->subscription + smsm->local_host);  in smsm_mask_irq()
249 	clear_bit(irq, entry->irq_enabled);  in smsm_mask_irq()
253  * smsm_unmask_irq() - subscribe to cascades of IRQs of a certain status bit
263 	struct qcom_smsm *smsm = entry->smsm;  in smsm_unmask_irq()
266 	/* Make sure our last cached state is up-to-date */  in smsm_unmask_irq()
267 	if (readl(entry->remote_state) & BIT(irq))  in smsm_unmask_irq()
268 		set_bit(irq, &entry->last_value);  in smsm_unmask_irq()
270 		clear_bit(irq, &entry->last_value);  in smsm_unmask_irq()
272 	set_bit(irq, entry->irq_enabled);  in smsm_unmask_irq()
274 	if (entry->subscription) {  in smsm_unmask_irq()
275 		val = readl(entry->subscription + smsm->local_host);  in smsm_unmask_irq()
277 		writel(val, entry->subscription + smsm->local_host);  in smsm_unmask_irq()
282  * smsm_set_irq_type() - updates the requested IRQ type for the cascading
283  * @irqd:	consumer interrupt handle
292 		return -EINVAL;  in smsm_set_irq_type()
295 		set_bit(irq, entry->irq_rising);  in smsm_set_irq_type()
297 		clear_bit(irq, entry->irq_rising);  in smsm_set_irq_type()
300 		set_bit(irq, entry->irq_falling);  in smsm_set_irq_type()
302 		clear_bit(irq, entry->irq_falling);  in smsm_set_irq_type()
315 		return -EINVAL;  in smsm_get_irqchip_state()
317 	val = readl(entry->remote_state);  in smsm_get_irqchip_state()
332  * smsm_irq_map() - sets up a mapping for a cascaded IRQ
341 	struct smsm_entry *entry = d->host_data;  in smsm_irq_map()
356  * smsm_parse_ipc() - parses a qcom,ipc-%d device tree property
361  * outgoing interrupts to a remote host - identified by @host_id.
366 	struct device_node *node = smsm->dev->of_node;  in smsm_parse_ipc()
367 	struct smsm_host *host = &smsm->hosts[host_id];  in smsm_parse_ipc()
371 	snprintf(key, sizeof(key), "qcom,ipc-%d", host_id);  in smsm_parse_ipc()
376 	host->ipc_regmap = syscon_node_to_regmap(syscon);  in smsm_parse_ipc()
378 	if (IS_ERR(host->ipc_regmap))  in smsm_parse_ipc()
379 		return PTR_ERR(host->ipc_regmap);  in smsm_parse_ipc()
381 	ret = of_property_read_u32_index(node, key, 1, &host->ipc_offset);  in smsm_parse_ipc()
383 		dev_err(smsm->dev, "no offset in %s\n", key);  in smsm_parse_ipc()
384 		return -EINVAL;  in smsm_parse_ipc()
387 	ret = of_property_read_u32_index(node, key, 2, &host->ipc_bit);  in smsm_parse_ipc()
389 		dev_err(smsm->dev, "no bit in %s\n", key);  in smsm_parse_ipc()
390 		return -EINVAL;  in smsm_parse_ipc()
397  * smsm_inbound_entry() - parse DT and set up an entry representing a remote system
411 		dev_err(smsm->dev, "failed to parse smsm interrupt\n");  in smsm_inbound_entry()
412 		return -EINVAL;  in smsm_inbound_entry()
415 	ret = devm_request_threaded_irq(smsm->dev, irq,  in smsm_inbound_entry()
420 		dev_err(smsm->dev, "failed to request interrupt\n");  in smsm_inbound_entry()
424 	entry->domain = irq_domain_add_linear(node, 32, &smsm_irq_ops, entry);  in smsm_inbound_entry()
425 	if (!entry->domain) {  in smsm_inbound_entry()
426 		dev_err(smsm->dev, "failed to add irq_domain\n");  in smsm_inbound_entry()
427 		return -ENOMEM;  in smsm_inbound_entry()
434  * smsm_get_size_info() - parse the optional memory segment for sizes
437  * Attempt to acquire the number of hosts and entries from the optional shared
455 	if (IS_ERR(info) && PTR_ERR(info) != -ENOENT) {  in smsm_get_size_info()
456 		if (PTR_ERR(info) != -EPROBE_DEFER)  in smsm_get_size_info()
457 			dev_err(smsm->dev, "unable to retrieve smsm size info\n");  in smsm_get_size_info()
460 		dev_warn(smsm->dev, "no smsm size info, using defaults\n");  in smsm_get_size_info()
461 		smsm->num_entries = SMSM_DEFAULT_NUM_ENTRIES;  in smsm_get_size_info()
462 		smsm->num_hosts = SMSM_DEFAULT_NUM_HOSTS;  in smsm_get_size_info()
466 	smsm->num_entries = info->num_entries;  in smsm_get_size_info()
467 	smsm->num_hosts = info->num_hosts;  in smsm_get_size_info()
469 	dev_dbg(smsm->dev,  in smsm_get_size_info()
471 		smsm->num_entries, smsm->num_hosts);  in smsm_get_size_info()
488 	smsm = devm_kzalloc(&pdev->dev, sizeof(*smsm), GFP_KERNEL);  in qcom_smsm_probe()
490 		return -ENOMEM;  in qcom_smsm_probe()
491 	smsm->dev = &pdev->dev;  in qcom_smsm_probe()
492 	spin_lock_init(&smsm->lock);  in qcom_smsm_probe()
498 	smsm->entries = devm_kcalloc(&pdev->dev,  in qcom_smsm_probe()
499 				     smsm->num_entries,  in qcom_smsm_probe()
502 	if (!smsm->entries)  in qcom_smsm_probe()
503 		return -ENOMEM;  in qcom_smsm_probe()
505 	smsm->hosts = devm_kcalloc(&pdev->dev,  in qcom_smsm_probe()
506 				   smsm->num_hosts,  in qcom_smsm_probe()
509 	if (!smsm->hosts)  in qcom_smsm_probe()
510 		return -ENOMEM;  in qcom_smsm_probe()
512 	for_each_child_of_node(pdev->dev.of_node, local_node) {  in qcom_smsm_probe()
513 		if (of_find_property(local_node, "#qcom,smem-state-cells", NULL))  in qcom_smsm_probe()
517 		dev_err(&pdev->dev, "no state entry\n");  in qcom_smsm_probe()
518 		return -EINVAL;  in qcom_smsm_probe()
521 	of_property_read_u32(pdev->dev.of_node,  in qcom_smsm_probe()
522 			     "qcom,local-host",  in qcom_smsm_probe()
523 			     &smsm->local_host);  in qcom_smsm_probe()
526 	for (id = 0; id < smsm->num_hosts; id++) {  in qcom_smsm_probe()
534 			      smsm->num_entries * sizeof(u32));  in qcom_smsm_probe()
535 	if (ret < 0 && ret != -EEXIST) {  in qcom_smsm_probe()
536 		dev_err(&pdev->dev, "unable to allocate shared state entry\n");  in qcom_smsm_probe()
542 		dev_err(&pdev->dev, "Unable to acquire shared state entry\n");  in qcom_smsm_probe()
547 	/* Acquire the list of interrupt mask vectors */  in qcom_smsm_probe()
548 	size = smsm->num_entries * smsm->num_hosts * sizeof(u32);  in qcom_smsm_probe()
550 	if (ret < 0 && ret != -EEXIST) {  in qcom_smsm_probe()
551 		dev_err(&pdev->dev, "unable to allocate smsm interrupt mask\n");  in qcom_smsm_probe()
557 		dev_err(&pdev->dev, "unable to acquire shared memory interrupt mask\n");  in qcom_smsm_probe()
563 	smsm->local_state = states + smsm->local_host;  in qcom_smsm_probe()
564 	smsm->subscription = intr_mask + smsm->local_host * smsm->num_hosts;  in qcom_smsm_probe()
567 	smsm->state = qcom_smem_state_register(local_node, &smsm_state_ops, smsm);  in qcom_smsm_probe()
568 	if (IS_ERR(smsm->state)) {  in qcom_smsm_probe()
569 		dev_err(smsm->dev, "failed to register qcom_smem_state\n");  in qcom_smsm_probe()
570 		ret = PTR_ERR(smsm->state);  in qcom_smsm_probe()
575 	for_each_available_child_of_node(pdev->dev.of_node, node) {  in qcom_smsm_probe()
576 		if (!of_property_read_bool(node, "interrupt-controller"))  in qcom_smsm_probe()
580 		if (ret || id >= smsm->num_entries) {  in qcom_smsm_probe()
581 			dev_err(&pdev->dev, "invalid reg of entry\n");  in qcom_smsm_probe()
583 				ret = -EINVAL;  in qcom_smsm_probe()
586 		entry = &smsm->entries[id];  in qcom_smsm_probe()
588 		entry->smsm = smsm;  in qcom_smsm_probe()
589 		entry->remote_state = states + id;  in qcom_smsm_probe()
592 		entry->subscription = intr_mask + id * smsm->num_hosts;  in qcom_smsm_probe()
593 		writel(0, entry->subscription + smsm->local_host);  in qcom_smsm_probe()
607 	for (id = 0; id < smsm->num_entries; id++)  in qcom_smsm_probe()
608 		if (smsm->entries[id].domain)  in qcom_smsm_probe()
609 			irq_domain_remove(smsm->entries[id].domain);  in qcom_smsm_probe()
611 	qcom_smem_state_unregister(smsm->state);  in qcom_smsm_probe()
622 	for (id = 0; id < smsm->num_entries; id++)  in qcom_smsm_remove()
623 		if (smsm->entries[id].domain)  in qcom_smsm_remove()
624 			irq_domain_remove(smsm->entries[id].domain);  in qcom_smsm_remove()
626 	qcom_smem_state_unregister(smsm->state);  in qcom_smsm_remove()
641 		.name  = "qcom-smsm",
647 MODULE_DESCRIPTION("Qualcomm Shared Memory State Machine driver");