[linux-2.6-block.git] / drivers / irqchip / irq-ti-sci-inta.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Texas Instruments' K3 Interrupt Aggregator irqchip driver
 *
 * Copyright (C) 2018-2019 Texas Instruments Incorporated - http://www.ti.com/
 *	Lokesh Vutla <lokeshvutla@ti.com>
 */

#include <linux/err.h>
#include <linux/io.h>
#include <linux/irqchip.h>
#include <linux/irqdomain.h>
#include <linux/interrupt.h>
#include <linux/msi.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_platform.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/soc/ti/ti_sci_inta_msi.h>
#include <linux/soc/ti/ti_sci_protocol.h>
#include <asm-generic/msi.h>

#define TI_SCI_DEV_ID_MASK	0xffff
#define TI_SCI_DEV_ID_SHIFT	16
#define TI_SCI_IRQ_ID_MASK	0xffff
#define TI_SCI_IRQ_ID_SHIFT	0
#define HWIRQ_TO_DEVID(hwirq)	(((hwirq) >> (TI_SCI_DEV_ID_SHIFT)) & \
				 (TI_SCI_DEV_ID_MASK))
#define HWIRQ_TO_IRQID(hwirq)	((hwirq) & (TI_SCI_IRQ_ID_MASK))
#define TO_HWIRQ(dev, index)	((((dev) & TI_SCI_DEV_ID_MASK) << \
				 TI_SCI_DEV_ID_SHIFT) | \
				((index) & TI_SCI_IRQ_ID_MASK))

#define MAX_EVENTS_PER_VINT	64
#define VINT_ENABLE_SET_OFFSET	0x0
#define VINT_ENABLE_CLR_OFFSET	0x8
#define VINT_STATUS_OFFSET	0x18

/**
 * struct ti_sci_inta_event_desc - Description of an event coming to
 *				   Interrupt Aggregator. This serves
 *				   as a mapping table for global event,
 *				   hwirq and vint bit.
 * @global_event:	Global event number corresponding to this event
 * @hwirq:		Hwirq of the incoming interrupt
 * @vint_bit:		Corresponding vint bit to which this event is attached.
 */
struct ti_sci_inta_event_desc {
	u16 global_event;
	u32 hwirq;
	u8 vint_bit;
};

/**
 * struct ti_sci_inta_vint_desc - Description of a virtual interrupt coming out
 *				  of Interrupt Aggregator.
 * @domain:		Pointer to IRQ domain to which this vint belongs.
 * @list:		List entry for the vint list
 * @event_map:		Bitmap to manage the allocation of events to vint.
 * @events:		Array of event descriptors assigned to this vint.
 * @parent_virq:	Linux IRQ number that gets attached to parent
 * @vint_id:		TISCI vint ID
 */
struct ti_sci_inta_vint_desc {
	struct irq_domain *domain;
	struct list_head list;
	DECLARE_BITMAP(event_map, MAX_EVENTS_PER_VINT);
	struct ti_sci_inta_event_desc events[MAX_EVENTS_PER_VINT];
	unsigned int parent_virq;
	u16 vint_id;
};

/**
 * struct ti_sci_inta_irq_domain - Structure representing a TISCI based
 *				   Interrupt Aggregator IRQ domain.
 * @sci:		Pointer to TISCI handle
 * @vint:		TISCI resource pointer representing IA inerrupts.
 * @global_event:	TISCI resource pointer representing global events.
 * @vint_list:		List of the vints active in the system
 * @vint_mutex:		Mutex to protect vint_list
 * @base:		Base address of the memory mapped IO registers
 * @pdev:		Pointer to platform device.
 */
struct ti_sci_inta_irq_domain {
	const struct ti_sci_handle *sci;
	struct ti_sci_resource *vint;
	struct ti_sci_resource *global_event;
	struct list_head vint_list;
	/* Mutex to protect vint list */
	struct mutex vint_mutex;
	void __iomem *base;
	struct platform_device *pdev;
};

#define to_vint_desc(e, i) container_of(e, struct ti_sci_inta_vint_desc, \
					events[i])

/**
 * ti_sci_inta_irq_handler() - Chained IRQ handler for the vint irqs
 * @desc:	Pointer to irq_desc corresponding to the irq
 */
static void ti_sci_inta_irq_handler(struct irq_desc *desc)
{
	struct ti_sci_inta_vint_desc *vint_desc;
	struct ti_sci_inta_irq_domain *inta;
	struct irq_domain *domain;
	unsigned int virq, bit;
	unsigned long val;

	vint_desc = irq_desc_get_handler_data(desc);
	domain = vint_desc->domain;
	inta = domain->host_data;

	chained_irq_enter(irq_desc_get_chip(desc), desc);

	val = readq_relaxed(inta->base + vint_desc->vint_id * 0x1000 +
			    VINT_STATUS_OFFSET);

	for_each_set_bit(bit, &val, MAX_EVENTS_PER_VINT) {
		virq = irq_find_mapping(domain, vint_desc->events[bit].hwirq);
		if (virq)
			generic_handle_irq(virq);
	}

	chained_irq_exit(irq_desc_get_chip(desc), desc);
}

/**
 * ti_sci_inta_alloc_parent_irq() - Allocate parent irq to Interrupt aggregator
 * @domain:	IRQ domain corresponding to Interrupt Aggregator
 *
 * Return 0 if all went well else corresponding error value.
 */
static struct ti_sci_inta_vint_desc *ti_sci_inta_alloc_parent_irq(struct irq_domain *domain)
{
	struct ti_sci_inta_irq_domain *inta = domain->host_data;
	struct ti_sci_inta_vint_desc *vint_desc;
	struct irq_fwspec parent_fwspec;
	unsigned int parent_virq;
	u16 vint_id;

	vint_id = ti_sci_get_free_resource(inta->vint);
	if (vint_id == TI_SCI_RESOURCE_NULL)
		return ERR_PTR(-EINVAL);

	vint_desc = kzalloc(sizeof(*vint_desc), GFP_KERNEL);
	if (!vint_desc)
		return ERR_PTR(-ENOMEM);

	vint_desc->domain = domain;
	vint_desc->vint_id = vint_id;
	INIT_LIST_HEAD(&vint_desc->list);

	parent_fwspec.fwnode = of_node_to_fwnode(of_irq_find_parent(dev_of_node(&inta->pdev->dev)));
	parent_fwspec.param_count = 2;
	parent_fwspec.param[0] = inta->pdev->id;
	parent_fwspec.param[1] = vint_desc->vint_id;

	parent_virq = irq_create_fwspec_mapping(&parent_fwspec);
	if (parent_virq == 0) {
		kfree(vint_desc);
		return ERR_PTR(-EINVAL);
	}
	vint_desc->parent_virq = parent_virq;

	list_add_tail(&vint_desc->list, &inta->vint_list);
	irq_set_chained_handler_and_data(vint_desc->parent_virq,
					 ti_sci_inta_irq_handler, vint_desc);

	return vint_desc;
}

/**
 * ti_sci_inta_alloc_event() - Attach an event to a IA vint.
 * @vint_desc:	Pointer to vint_desc to which the event gets attached
 * @free_bit:	Bit inside vint to which event gets attached
 * @hwirq:	hwirq of the input event
 *
 * Return event_desc pointer if all went ok else appropriate error value.
 */
static struct ti_sci_inta_event_desc *ti_sci_inta_alloc_event(struct ti_sci_inta_vint_desc *vint_desc,
							      u16 free_bit,
							      u32 hwirq)
{
	struct ti_sci_inta_irq_domain *inta = vint_desc->domain->host_data;
	struct ti_sci_inta_event_desc *event_desc;
	u16 dev_id, dev_index;
	int err;

	dev_id = HWIRQ_TO_DEVID(hwirq);
	dev_index = HWIRQ_TO_IRQID(hwirq);

	event_desc = &vint_desc->events[free_bit];
	event_desc->hwirq = hwirq;
	event_desc->vint_bit = free_bit;
	event_desc->global_event = ti_sci_get_free_resource(inta->global_event);
	if (event_desc->global_event == TI_SCI_RESOURCE_NULL)
		return ERR_PTR(-EINVAL);

	err = inta->sci->ops.rm_irq_ops.set_event_map(inta->sci,
						      dev_id, dev_index,
						      inta->pdev->id,
						      vint_desc->vint_id,
						      event_desc->global_event,
						      free_bit);
	if (err)
		goto free_global_event;

	return event_desc;
free_global_event:
	ti_sci_release_resource(inta->global_event, event_desc->global_event);
	return ERR_PTR(err);
}

/**
 * ti_sci_inta_alloc_irq() -  Allocate an irq within INTA domain
 * @domain:	irq_domain pointer corresponding to INTA
 * @hwirq:	hwirq of the input event
 *
 * Note: Allocation happens in the following manner:
 *	- Find a free bit available in any of the vints available in the list.
 *	- If not found, allocate a vint from the vint pool
 *	- Attach the free bit to input hwirq.
 * Return event_desc if all went ok else appropriate error value.
 */
static struct ti_sci_inta_event_desc *ti_sci_inta_alloc_irq(struct irq_domain *domain,
							    u32 hwirq)
{
	struct ti_sci_inta_irq_domain *inta = domain->host_data;
	struct ti_sci_inta_vint_desc *vint_desc = NULL;
	struct ti_sci_inta_event_desc *event_desc;
	u16 free_bit;

	mutex_lock(&inta->vint_mutex);
	list_for_each_entry(vint_desc, &inta->vint_list, list) {
		free_bit = find_first_zero_bit(vint_desc->event_map,
					       MAX_EVENTS_PER_VINT);
		if (free_bit != MAX_EVENTS_PER_VINT) {
			set_bit(free_bit, vint_desc->event_map);
			goto alloc_event;
		}
	}

	/* No free bits available. Allocate a new vint */
	vint_desc = ti_sci_inta_alloc_parent_irq(domain);
	if (IS_ERR(vint_desc)) {
		mutex_unlock(&inta->vint_mutex);
		return ERR_PTR(PTR_ERR(vint_desc));
	}

	free_bit = find_first_zero_bit(vint_desc->event_map,
				       MAX_EVENTS_PER_VINT);
	set_bit(free_bit, vint_desc->event_map);

alloc_event:
	event_desc = ti_sci_inta_alloc_event(vint_desc, free_bit, hwirq);
	if (IS_ERR(event_desc))
		clear_bit(free_bit, vint_desc->event_map);

	mutex_unlock(&inta->vint_mutex);
	return event_desc;
}

/**
 * ti_sci_inta_free_parent_irq() - Free a parent irq to INTA
 * @inta:	Pointer to inta domain.
 * @vint_desc:	Pointer to vint_desc that needs to be freed.
 */
static void ti_sci_inta_free_parent_irq(struct ti_sci_inta_irq_domain *inta,
					struct ti_sci_inta_vint_desc *vint_desc)
{
	if (find_first_bit(vint_desc->event_map, MAX_EVENTS_PER_VINT) == MAX_EVENTS_PER_VINT) {
		list_del(&vint_desc->list);
		ti_sci_release_resource(inta->vint, vint_desc->vint_id);
		irq_dispose_mapping(vint_desc->parent_virq);
		kfree(vint_desc);
	}
}

/**
 * ti_sci_inta_free_irq() - Free an IRQ within INTA domain
 * @event_desc:	Pointer to event_desc that needs to be freed.
 * @hwirq:	Hwirq number within INTA domain that needs to be freed
 */
static void ti_sci_inta_free_irq(struct ti_sci_inta_event_desc *event_desc,
				 u32 hwirq)
{
	struct ti_sci_inta_vint_desc *vint_desc;
	struct ti_sci_inta_irq_domain *inta;

	vint_desc = to_vint_desc(event_desc, event_desc->vint_bit);
	inta = vint_desc->domain->host_data;
	/* free event irq */
	mutex_lock(&inta->vint_mutex);
	inta->sci->ops.rm_irq_ops.free_event_map(inta->sci,
						 HWIRQ_TO_DEVID(hwirq),
						 HWIRQ_TO_IRQID(hwirq),
						 inta->pdev->id,
						 vint_desc->vint_id,
						 event_desc->global_event,
						 event_desc->vint_bit);

	clear_bit(event_desc->vint_bit, vint_desc->event_map);
	ti_sci_release_resource(inta->global_event, event_desc->global_event);
	event_desc->global_event = TI_SCI_RESOURCE_NULL;
	event_desc->hwirq = 0;

	ti_sci_inta_free_parent_irq(inta, vint_desc);
	mutex_unlock(&inta->vint_mutex);
}

/**
 * ti_sci_inta_request_resources() - Allocate resources for input irq
 * @data: Pointer to corresponding irq_data
 *
 * Note: This is the core api where the actual allocation happens for input
 *	 hwirq. This allocation involves creating a parent irq for vint.
 *	 If this is done in irq_domain_ops.alloc() then a deadlock is reached
 *	 for allocation. So this allocation is being done in request_resources()
 *
 * Return: 0 if all went well else corresponding error.
 */
static int ti_sci_inta_request_resources(struct irq_data *data)
{
	struct ti_sci_inta_event_desc *event_desc;

	event_desc = ti_sci_inta_alloc_irq(data->domain, data->hwirq);
	if (IS_ERR(event_desc))
		return PTR_ERR(event_desc);

	data->chip_data = event_desc;

	return 0;
}

/**
 * ti_sci_inta_release_resources - Release resources for input irq
 * @data: Pointer to corresponding irq_data
 *
 * Note: Corresponding to request_resources(), all the unmapping and deletion
 *	 of parent vint irqs happens in this api.
 */
static void ti_sci_inta_release_resources(struct irq_data *data)
{
	struct ti_sci_inta_event_desc *event_desc;

	event_desc = irq_data_get_irq_chip_data(data);
	ti_sci_inta_free_irq(event_desc, data->hwirq);
}

/**
 * ti_sci_inta_manage_event() - Control the event based on the offset
 * @data:	Pointer to corresponding irq_data
 * @offset:	register offset using which event is controlled.
 */
static void ti_sci_inta_manage_event(struct irq_data *data, u32 offset)
{
	struct ti_sci_inta_event_desc *event_desc;
	struct ti_sci_inta_vint_desc *vint_desc;
	struct ti_sci_inta_irq_domain *inta;

	event_desc = irq_data_get_irq_chip_data(data);
	vint_desc = to_vint_desc(event_desc, event_desc->vint_bit);
	inta = data->domain->host_data;

	writeq_relaxed(BIT(event_desc->vint_bit),
		       inta->base + vint_desc->vint_id * 0x1000 + offset);
}

/**
 * ti_sci_inta_mask_irq() - Mask an event
 * @data:	Pointer to corresponding irq_data
 */
static void ti_sci_inta_mask_irq(struct irq_data *data)
{
	ti_sci_inta_manage_event(data, VINT_ENABLE_CLR_OFFSET);
}

/**
 * ti_sci_inta_unmask_irq() - Unmask an event
 * @data:	Pointer to corresponding irq_data
 */
static void ti_sci_inta_unmask_irq(struct irq_data *data)
{
	ti_sci_inta_manage_event(data, VINT_ENABLE_SET_OFFSET);
}

/**
 * ti_sci_inta_ack_irq() - Ack an event
 * @data:	Pointer to corresponding irq_data
 */
static void ti_sci_inta_ack_irq(struct irq_data *data)
{
	/*
	 * Do not clear the event if hardware is capable of sending
	 * a down event.
	 */
	if (irqd_get_trigger_type(data) != IRQF_TRIGGER_HIGH)
		ti_sci_inta_manage_event(data, VINT_STATUS_OFFSET);
}

static int ti_sci_inta_set_affinity(struct irq_data *d,
				    const struct cpumask *mask_val, bool force)
{
	return -EINVAL;
}

/**
 * ti_sci_inta_set_type() - Update the trigger type of the irq.
 * @data:	Pointer to corresponding irq_data
 * @type:	Trigger type as specified by user
 *
 * Note: This updates the handle_irq callback for level msi.
 *
 * Return 0 if all went well else appropriate error.
 */
static int ti_sci_inta_set_type(struct irq_data *data, unsigned int type)
{
	/*
	 * .alloc default sets handle_edge_irq. But if the user specifies
	 * that IRQ is level MSI, then update the handle to handle_level_irq
	 */
	switch (type & IRQ_TYPE_SENSE_MASK) {
	case IRQF_TRIGGER_HIGH:
		irq_set_handler_locked(data, handle_level_irq);
		return 0;
	case IRQF_TRIGGER_RISING:
		return 0;
	default:
		return -EINVAL;
	}

	return -EINVAL;
}

static struct irq_chip ti_sci_inta_irq_chip = {
	.name			= "INTA",
	.irq_ack		= ti_sci_inta_ack_irq,
	.irq_mask		= ti_sci_inta_mask_irq,
	.irq_set_type		= ti_sci_inta_set_type,
	.irq_unmask		= ti_sci_inta_unmask_irq,
	.irq_set_affinity	= ti_sci_inta_set_affinity,
	.irq_request_resources	= ti_sci_inta_request_resources,
	.irq_release_resources	= ti_sci_inta_release_resources,
};

/**
 * ti_sci_inta_irq_domain_free() - Free an IRQ from the IRQ domain
 * @domain:	Domain to which the irqs belong
 * @virq:	base linux virtual IRQ to be freed.
 * @nr_irqs:	Number of continuous irqs to be freed
 */
static void ti_sci_inta_irq_domain_free(struct irq_domain *domain,
					unsigned int virq, unsigned int nr_irqs)
{
	struct irq_data *data = irq_domain_get_irq_data(domain, virq);

	irq_domain_reset_irq_data(data);
}

/**
 * ti_sci_inta_irq_domain_alloc() - Allocate Interrupt aggregator IRQs
 * @domain:	Point to the interrupt aggregator IRQ domain
 * @virq:	Corresponding Linux virtual IRQ number
 * @nr_irqs:	Continuous irqs to be allocated
 * @data:	Pointer to firmware specifier
 *
 * No actual allocation happens here.
 *
 * Return 0 if all went well else appropriate error value.
 */
static int ti_sci_inta_irq_domain_alloc(struct irq_domain *domain,
					unsigned int virq, unsigned int nr_irqs,
					void *data)
{
	msi_alloc_info_t *arg = data;

	irq_domain_set_info(domain, virq, arg->hwirq, &ti_sci_inta_irq_chip,
			    NULL, handle_edge_irq, NULL, NULL);

	return 0;
}

static const struct irq_domain_ops ti_sci_inta_irq_domain_ops = {
	.free		= ti_sci_inta_irq_domain_free,
	.alloc		= ti_sci_inta_irq_domain_alloc,
};

static struct irq_chip ti_sci_inta_msi_irq_chip = {
	.name			= "MSI-INTA",
	.flags			= IRQCHIP_SUPPORTS_LEVEL_MSI,
};

static void ti_sci_inta_msi_set_desc(msi_alloc_info_t *arg,
				     struct msi_desc *desc)
{
	struct platform_device *pdev = to_platform_device(desc->dev);

	arg->desc = desc;
	arg->hwirq = TO_HWIRQ(pdev->id, desc->inta.dev_index);
}

static struct msi_domain_ops ti_sci_inta_msi_ops = {
	.set_desc	= ti_sci_inta_msi_set_desc,
};

static struct msi_domain_info ti_sci_inta_msi_domain_info = {
	.flags	= (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
		   MSI_FLAG_LEVEL_CAPABLE),
	.ops	= &ti_sci_inta_msi_ops,
	.chip	= &ti_sci_inta_msi_irq_chip,
};

static int ti_sci_inta_irq_domain_probe(struct platform_device *pdev)
{
	struct irq_domain *parent_domain, *domain, *msi_domain;
	struct device_node *parent_node, *node;
	struct ti_sci_inta_irq_domain *inta;
	struct device *dev = &pdev->dev;
	struct resource *res;
	int ret;

	node = dev_of_node(dev);
	parent_node = of_irq_find_parent(node);
	if (!parent_node) {
		dev_err(dev, "Failed to get IRQ parent node\n");
		return -ENODEV;
	}

	parent_domain = irq_find_host(parent_node);
	if (!parent_domain)
		return -EPROBE_DEFER;

	inta = devm_kzalloc(dev, sizeof(*inta), GFP_KERNEL);
	if (!inta)
		return -ENOMEM;

	inta->pdev = pdev;
	inta->sci = devm_ti_sci_get_by_phandle(dev, "ti,sci");
	if (IS_ERR(inta->sci)) {
		ret = PTR_ERR(inta->sci);
		if (ret != -EPROBE_DEFER)
			dev_err(dev, "ti,sci read fail %d\n", ret);
		inta->sci = NULL;
		return ret;
	}

	ret = of_property_read_u32(dev->of_node, "ti,sci-dev-id", &pdev->id);
	if (ret) {
		dev_err(dev, "missing 'ti,sci-dev-id' property\n");
		return -EINVAL;
	}

	inta->vint = devm_ti_sci_get_of_resource(inta->sci, dev, pdev->id,
						 "ti,sci-rm-range-vint");
	if (IS_ERR(inta->vint)) {
		dev_err(dev, "VINT resource allocation failed\n");
		return PTR_ERR(inta->vint);
	}

	inta->global_event = devm_ti_sci_get_of_resource(inta->sci, dev, pdev->id,
						"ti,sci-rm-range-global-event");
	if (IS_ERR(inta->global_event)) {
		dev_err(dev, "Global event resource allocation failed\n");
		return PTR_ERR(inta->global_event);
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	inta->base = devm_ioremap_resource(dev, res);
	if (IS_ERR(inta->base))
		return -ENODEV;

	domain = irq_domain_add_linear(dev_of_node(dev),
				       ti_sci_get_num_resources(inta->vint),
				       &ti_sci_inta_irq_domain_ops, inta);
	if (!domain) {
		dev_err(dev, "Failed to allocate IRQ domain\n");
		return -ENOMEM;
	}

	msi_domain = ti_sci_inta_msi_create_irq_domain(of_node_to_fwnode(node),
						&ti_sci_inta_msi_domain_info,
						domain);
	if (!msi_domain) {
		irq_domain_remove(domain);
		dev_err(dev, "Failed to allocate msi domain\n");
		return -ENOMEM;
	}

	INIT_LIST_HEAD(&inta->vint_list);
	mutex_init(&inta->vint_mutex);

	return 0;
}

static const struct of_device_id ti_sci_inta_irq_domain_of_match[] = {
	{ .compatible = "ti,sci-inta", },
	{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, ti_sci_inta_irq_domain_of_match);

static struct platform_driver ti_sci_inta_irq_domain_driver = {
	.probe = ti_sci_inta_irq_domain_probe,
	.driver = {
		.name = "ti-sci-inta",
		.of_match_table = ti_sci_inta_irq_domain_of_match,
	},
};
module_platform_driver(ti_sci_inta_irq_domain_driver);

MODULE_AUTHOR("Lokesh Vutla <lokeshvutla@ticom>");
MODULE_DESCRIPTION("K3 Interrupt Aggregator driver over TI SCI protocol");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
9f1463b8 LV	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* Texas Instruments' K3 Interrupt Aggregator irqchip driver
	4	*
	5	* Copyright (C) 2018-2019 Texas Instruments Incorporated - http://www.ti.com/
	6	* Lokesh Vutla <lokeshvutla@ti.com>
	7	*/
	8
	9	#include <linux/err.h>
	10	#include <linux/io.h>
	11	#include <linux/irqchip.h>
	12	#include <linux/irqdomain.h>
	13	#include <linux/interrupt.h>
	14	#include <linux/msi.h>
	15	#include <linux/module.h>
	16	#include <linux/moduleparam.h>
	17	#include <linux/of_address.h>
	18	#include <linux/of_irq.h>
	19	#include <linux/of_platform.h>
	20	#include <linux/irqchip/chained_irq.h>
f011df61	21	#include <linux/soc/ti/ti_sci_inta_msi.h>
9f1463b8 LV	22	#include <linux/soc/ti/ti_sci_protocol.h>
	23	#include <asm-generic/msi.h>
	24
	25	#define TI_SCI_DEV_ID_MASK 0xffff
	26	#define TI_SCI_DEV_ID_SHIFT 16
	27	#define TI_SCI_IRQ_ID_MASK 0xffff
	28	#define TI_SCI_IRQ_ID_SHIFT 0
	29	#define HWIRQ_TO_DEVID(hwirq) (((hwirq) >> (TI_SCI_DEV_ID_SHIFT)) & \
	30	(TI_SCI_DEV_ID_MASK))
	31	#define HWIRQ_TO_IRQID(hwirq) ((hwirq) & (TI_SCI_IRQ_ID_MASK))
f011df61 LV	32	#define TO_HWIRQ(dev, index) ((((dev) & TI_SCI_DEV_ID_MASK) << \
	33	TI_SCI_DEV_ID_SHIFT) \| \
	34	((index) & TI_SCI_IRQ_ID_MASK))
9f1463b8 LV	35
	36	#define MAX_EVENTS_PER_VINT 64
	37	#define VINT_ENABLE_SET_OFFSET 0x0
	38	#define VINT_ENABLE_CLR_OFFSET 0x8
	39	#define VINT_STATUS_OFFSET 0x18
	40
	41	/**
	42	* struct ti_sci_inta_event_desc - Description of an event coming to
	43	* Interrupt Aggregator. This serves
	44	* as a mapping table for global event,
	45	* hwirq and vint bit.
	46	* @global_event: Global event number corresponding to this event
	47	* @hwirq: Hwirq of the incoming interrupt
	48	* @vint_bit: Corresponding vint bit to which this event is attached.
	49	*/
	50	struct ti_sci_inta_event_desc {
	51	u16 global_event;
	52	u32 hwirq;
	53	u8 vint_bit;
	54	};
	55
	56	/**
	57	* struct ti_sci_inta_vint_desc - Description of a virtual interrupt coming out
	58	* of Interrupt Aggregator.
	59	* @domain: Pointer to IRQ domain to which this vint belongs.
	60	* @list: List entry for the vint list
	61	* @event_map: Bitmap to manage the allocation of events to vint.
	62	* @events: Array of event descriptors assigned to this vint.
	63	* @parent_virq: Linux IRQ number that gets attached to parent
	64	* @vint_id: TISCI vint ID
	65	*/
	66	struct ti_sci_inta_vint_desc {
	67	struct irq_domain *domain;
	68	struct list_head list;
	69	DECLARE_BITMAP(event_map, MAX_EVENTS_PER_VINT);
	70	struct ti_sci_inta_event_desc events[MAX_EVENTS_PER_VINT];
	71	unsigned int parent_virq;
	72	u16 vint_id;
	73	};
	74
	75	/**
	76	* struct ti_sci_inta_irq_domain - Structure representing a TISCI based
	77	* Interrupt Aggregator IRQ domain.
	78	* @sci: Pointer to TISCI handle
	79	* @vint: TISCI resource pointer representing IA inerrupts.
	80	* @global_event: TISCI resource pointer representing global events.
	81	* @vint_list: List of the vints active in the system
	82	* @vint_mutex: Mutex to protect vint_list
	83	* @base: Base address of the memory mapped IO registers
	84	* @pdev: Pointer to platform device.
	85	*/
	86	struct ti_sci_inta_irq_domain {
	87	const struct ti_sci_handle *sci;
	88	struct ti_sci_resource *vint;
	89	struct ti_sci_resource *global_event;
	90	struct list_head vint_list;
	91	/* Mutex to protect vint list */
	92	struct mutex vint_mutex;
	93	void __iomem *base;
	94	struct platform_device *pdev;
	95	};
	96
	97	#define to_vint_desc(e, i) container_of(e, struct ti_sci_inta_vint_desc, \
	98	events[i])
99
100	/**
101	* ti_sci_inta_irq_handler() - Chained IRQ handler for the vint irqs
102	* @desc: Pointer to irq_desc corresponding to the irq
103	*/
104	static void ti_sci_inta_irq_handler(struct irq_desc *desc)
105	{
106	struct ti_sci_inta_vint_desc *vint_desc;
107	struct ti_sci_inta_irq_domain *inta;
108	struct irq_domain *domain;
109	unsigned int virq, bit;
110	unsigned long val;
111
112	vint_desc = irq_desc_get_handler_data(desc);
113	domain = vint_desc->domain;
114	inta = domain->host_data;
115
116	chained_irq_enter(irq_desc_get_chip(desc), desc);
117
118	val = readq_relaxed(inta->base + vint_desc->vint_id * 0x1000 +
119	VINT_STATUS_OFFSET);
120
121	for_each_set_bit(bit, &val, MAX_EVENTS_PER_VINT) {
122	virq = irq_find_mapping(domain, vint_desc->events[bit].hwirq);
123	if (virq)
124	generic_handle_irq(virq);
125	}
126
127	chained_irq_exit(irq_desc_get_chip(desc), desc);
128	}
129
130	/**
131	* ti_sci_inta_alloc_parent_irq() - Allocate parent irq to Interrupt aggregator
132	* @domain: IRQ domain corresponding to Interrupt Aggregator
133	*
134	* Return 0 if all went well else corresponding error value.
135	*/
136	static struct ti_sci_inta_vint_desc ti_sci_inta_alloc_parent_irq(struct irq_domain domain)
137	{
138	struct ti_sci_inta_irq_domain *inta = domain->host_data;
139	struct ti_sci_inta_vint_desc *vint_desc;
140	struct irq_fwspec parent_fwspec;
141	unsigned int parent_virq;
142	u16 vint_id;
143
144	vint_id = ti_sci_get_free_resource(inta->vint);
145	if (vint_id == TI_SCI_RESOURCE_NULL)
146	return ERR_PTR(-EINVAL);
147
148	vint_desc = kzalloc(sizeof(*vint_desc), GFP_KERNEL);
149	if (!vint_desc)
150	return ERR_PTR(-ENOMEM);
151
152	vint_desc->domain = domain;
153	vint_desc->vint_id = vint_id;
154	INIT_LIST_HEAD(&vint_desc->list);
155
156	parent_fwspec.fwnode = of_node_to_fwnode(of_irq_find_parent(dev_of_node(&inta->pdev->dev)));
157	parent_fwspec.param_count = 2;
158	parent_fwspec.param[0] = inta->pdev->id;
159	parent_fwspec.param[1] = vint_desc->vint_id;
160
161	parent_virq = irq_create_fwspec_mapping(&parent_fwspec);
eb737b8f	162	if (parent_virq == 0) {
9f1463b8	163	kfree(vint_desc);
eb737b8f	164	return ERR_PTR(-EINVAL);
9f1463b8 LV	165	}
	166	vint_desc->parent_virq = parent_virq;
	167
	168	list_add_tail(&vint_desc->list, &inta->vint_list);
	169	irq_set_chained_handler_and_data(vint_desc->parent_virq,
	170	ti_sci_inta_irq_handler, vint_desc);
	171
	172	return vint_desc;
	173	}
	174
	175	/**
	176	* ti_sci_inta_alloc_event() - Attach an event to a IA vint.
	177	* @vint_desc: Pointer to vint_desc to which the event gets attached
	178	* @free_bit: Bit inside vint to which event gets attached
	179	* @hwirq: hwirq of the input event
	180	*
	181	* Return event_desc pointer if all went ok else appropriate error value.
	182	*/
	183	static struct ti_sci_inta_event_desc ti_sci_inta_alloc_event(struct ti_sci_inta_vint_desc vint_desc,
	184	u16 free_bit,
	185	u32 hwirq)
	186	{
	187	struct ti_sci_inta_irq_domain *inta = vint_desc->domain->host_data;
	188	struct ti_sci_inta_event_desc *event_desc;
	189	u16 dev_id, dev_index;
	190	int err;
	191
	192	dev_id = HWIRQ_TO_DEVID(hwirq);
	193	dev_index = HWIRQ_TO_IRQID(hwirq);
	194
	195	event_desc = &vint_desc->events[free_bit];
	196	event_desc->hwirq = hwirq;
	197	event_desc->vint_bit = free_bit;
	198	event_desc->global_event = ti_sci_get_free_resource(inta->global_event);
	199	if (event_desc->global_event == TI_SCI_RESOURCE_NULL)
	200	return ERR_PTR(-EINVAL);
	201
	202	err = inta->sci->ops.rm_irq_ops.set_event_map(inta->sci,
	203	dev_id, dev_index,
	204	inta->pdev->id,
	205	vint_desc->vint_id,
	206	event_desc->global_event,
	207	free_bit);
	208	if (err)
	209	goto free_global_event;
	210
	211	return event_desc;
	212	free_global_event:
	213	ti_sci_release_resource(inta->global_event, event_desc->global_event);
	214	return ERR_PTR(err);
	215	}
	216
	217	/**
	218	* ti_sci_inta_alloc_irq() - Allocate an irq within INTA domain
	219	* @domain: irq_domain pointer corresponding to INTA
	220	* @hwirq: hwirq of the input event
	221	*
	222	* Note: Allocation happens in the following manner:
	223	* - Find a free bit available in any of the vints available in the list.
	224	* - If not found, allocate a vint from the vint pool
	225	* - Attach the free bit to input hwirq.
	226	* Return event_desc if all went ok else appropriate error value.
	227	*/
	228	static struct ti_sci_inta_event_desc ti_sci_inta_alloc_irq(struct irq_domain domain,
229	u32 hwirq)
230	{
231	struct ti_sci_inta_irq_domain *inta = domain->host_data;
232	struct ti_sci_inta_vint_desc *vint_desc = NULL;
233	struct ti_sci_inta_event_desc *event_desc;
234	u16 free_bit;
235
236	mutex_lock(&inta->vint_mutex);
237	list_for_each_entry(vint_desc, &inta->vint_list, list) {
238	free_bit = find_first_zero_bit(vint_desc->event_map,
239	MAX_EVENTS_PER_VINT);
240	if (free_bit != MAX_EVENTS_PER_VINT) {
241	set_bit(free_bit, vint_desc->event_map);
242	goto alloc_event;
243	}
244	}
245
246	/* No free bits available. Allocate a new vint */
247	vint_desc = ti_sci_inta_alloc_parent_irq(domain);
248	if (IS_ERR(vint_desc)) {
249	mutex_unlock(&inta->vint_mutex);
250	return ERR_PTR(PTR_ERR(vint_desc));
251	}
252
253	free_bit = find_first_zero_bit(vint_desc->event_map,
254	MAX_EVENTS_PER_VINT);
255	set_bit(free_bit, vint_desc->event_map);
256
257	alloc_event:
258	event_desc = ti_sci_inta_alloc_event(vint_desc, free_bit, hwirq);
259	if (IS_ERR(event_desc))
260	clear_bit(free_bit, vint_desc->event_map);
261
262	mutex_unlock(&inta->vint_mutex);
263	return event_desc;
264	}
265
266	/**
267	* ti_sci_inta_free_parent_irq() - Free a parent irq to INTA
268	* @inta: Pointer to inta domain.
269	* @vint_desc: Pointer to vint_desc that needs to be freed.
270	*/
271	static void ti_sci_inta_free_parent_irq(struct ti_sci_inta_irq_domain *inta,
272	struct ti_sci_inta_vint_desc *vint_desc)
273	{
274	if (find_first_bit(vint_desc->event_map, MAX_EVENTS_PER_VINT) == MAX_EVENTS_PER_VINT) {
275	list_del(&vint_desc->list);
276	ti_sci_release_resource(inta->vint, vint_desc->vint_id);
277	irq_dispose_mapping(vint_desc->parent_virq);
278	kfree(vint_desc);
279	}
280	}
281
282	/**
283	* ti_sci_inta_free_irq() - Free an IRQ within INTA domain
284	* @event_desc: Pointer to event_desc that needs to be freed.
285	* @hwirq: Hwirq number within INTA domain that needs to be freed
286	*/
287	static void ti_sci_inta_free_irq(struct ti_sci_inta_event_desc *event_desc,
288	u32 hwirq)
289	{
290	struct ti_sci_inta_vint_desc *vint_desc;
291	struct ti_sci_inta_irq_domain *inta;
292
293	vint_desc = to_vint_desc(event_desc, event_desc->vint_bit);
294	inta = vint_desc->domain->host_data;
295	/* free event irq */
296	mutex_lock(&inta->vint_mutex);
297	inta->sci->ops.rm_irq_ops.free_event_map(inta->sci,
298	HWIRQ_TO_DEVID(hwirq),
299	HWIRQ_TO_IRQID(hwirq),
300	inta->pdev->id,
301	vint_desc->vint_id,
302	event_desc->global_event,
303	event_desc->vint_bit);
304
305	clear_bit(event_desc->vint_bit, vint_desc->event_map);
306	ti_sci_release_resource(inta->global_event, event_desc->global_event);
307	event_desc->global_event = TI_SCI_RESOURCE_NULL;
308	event_desc->hwirq = 0;
309
310	ti_sci_inta_free_parent_irq(inta, vint_desc);
311	mutex_unlock(&inta->vint_mutex);
312	}
313
314	/**
315	* ti_sci_inta_request_resources() - Allocate resources for input irq
316	* @data: Pointer to corresponding irq_data
317	*
318	* Note: This is the core api where the actual allocation happens for input
319	* hwirq. This allocation involves creating a parent irq for vint.
320	* If this is done in irq_domain_ops.alloc() then a deadlock is reached
321	* for allocation. So this allocation is being done in request_resources()
322	*
323	* Return: 0 if all went well else corresponding error.
324	*/
325	static int ti_sci_inta_request_resources(struct irq_data *data)
326	{
327	struct ti_sci_inta_event_desc *event_desc;
328
329	event_desc = ti_sci_inta_alloc_irq(data->domain, data->hwirq);
330	if (IS_ERR(event_desc))
331	return PTR_ERR(event_desc);
332
333	data->chip_data = event_desc;
334
335	return 0;
336	}
337
338	/**
339	* ti_sci_inta_release_resources - Release resources for input irq
340	* @data: Pointer to corresponding irq_data
341	*
342	* Note: Corresponding to request_resources(), all the unmapping and deletion
343	* of parent vint irqs happens in this api.
344	*/
345	static void ti_sci_inta_release_resources(struct irq_data *data)
346	{
347	struct ti_sci_inta_event_desc *event_desc;
348
349	event_desc = irq_data_get_irq_chip_data(data);
350	ti_sci_inta_free_irq(event_desc, data->hwirq);
351	}
352
353	/**
354	* ti_sci_inta_manage_event() - Control the event based on the offset
355	* @data: Pointer to corresponding irq_data
356	* @offset: register offset using which event is controlled.
357	*/
358	static void ti_sci_inta_manage_event(struct irq_data *data, u32 offset)
359	{
360	struct ti_sci_inta_event_desc *event_desc;
361	struct ti_sci_inta_vint_desc *vint_desc;
362	struct ti_sci_inta_irq_domain *inta;
363
364	event_desc = irq_data_get_irq_chip_data(data);
365	vint_desc = to_vint_desc(event_desc, event_desc->vint_bit);
366	inta = data->domain->host_data;
367
368	writeq_relaxed(BIT(event_desc->vint_bit),
369	inta->base + vint_desc->vint_id * 0x1000 + offset);
370	}
371
372	/**
373	* ti_sci_inta_mask_irq() - Mask an event
374	* @data: Pointer to corresponding irq_data
375	*/
376	static void ti_sci_inta_mask_irq(struct irq_data *data)
377	{
378	ti_sci_inta_manage_event(data, VINT_ENABLE_CLR_OFFSET);
379	}
380
381	/**
382	* ti_sci_inta_unmask_irq() - Unmask an event
383	* @data: Pointer to corresponding irq_data
384	*/
385	static void ti_sci_inta_unmask_irq(struct irq_data *data)
386	{
387	ti_sci_inta_manage_event(data, VINT_ENABLE_SET_OFFSET);
388	}
389
390	/**
391	* ti_sci_inta_ack_irq() - Ack an event
392	* @data: Pointer to corresponding irq_data
393	*/
394	static void ti_sci_inta_ack_irq(struct irq_data *data)
395	{
396	/*
397	* Do not clear the event if hardware is capable of sending
398	* a down event.
399	*/
400	if (irqd_get_trigger_type(data) != IRQF_TRIGGER_HIGH)
401	ti_sci_inta_manage_event(data, VINT_STATUS_OFFSET);
402	}
403
404	static int ti_sci_inta_set_affinity(struct irq_data *d,
405	const struct cpumask *mask_val, bool force)
406	{
407	return -EINVAL;
408	}
409
410	/**
411	* ti_sci_inta_set_type() - Update the trigger type of the irq.
412	* @data: Pointer to corresponding irq_data
413	* @type: Trigger type as specified by user
414	*
415	* Note: This updates the handle_irq callback for level msi.
416	*
417	* Return 0 if all went well else appropriate error.
418	*/
419	static int ti_sci_inta_set_type(struct irq_data *data, unsigned int type)
420	{
421	/*
422	* .alloc default sets handle_edge_irq. But if the user specifies
423	* that IRQ is level MSI, then update the handle to handle_level_irq
424	*/
425	switch (type & IRQ_TYPE_SENSE_MASK) {
426	case IRQF_TRIGGER_HIGH:
427	irq_set_handler_locked(data, handle_level_irq);
428	return 0;
429	case IRQF_TRIGGER_RISING:
430	return 0;
431	default:
432	return -EINVAL;
433	}
434
435	return -EINVAL;
436	}
437
438	static struct irq_chip ti_sci_inta_irq_chip = {
439	.name = "INTA",
440	.irq_ack = ti_sci_inta_ack_irq,
441	.irq_mask = ti_sci_inta_mask_irq,
442	.irq_set_type = ti_sci_inta_set_type,
443	.irq_unmask = ti_sci_inta_unmask_irq,
444	.irq_set_affinity = ti_sci_inta_set_affinity,
445	.irq_request_resources = ti_sci_inta_request_resources,
446	.irq_release_resources = ti_sci_inta_release_resources,
447	};
448
449	/**
450	* ti_sci_inta_irq_domain_free() - Free an IRQ from the IRQ domain
451	* @domain: Domain to which the irqs belong
452	* @virq: base linux virtual IRQ to be freed.
453	* @nr_irqs: Number of continuous irqs to be freed
454	*/
455	static void ti_sci_inta_irq_domain_free(struct irq_domain *domain,
456	unsigned int virq, unsigned int nr_irqs)
457	{
458	struct irq_data *data = irq_domain_get_irq_data(domain, virq);
459
460	irq_domain_reset_irq_data(data);
461	}
462
463	/**
464	* ti_sci_inta_irq_domain_alloc() - Allocate Interrupt aggregator IRQs
465	* @domain: Point to the interrupt aggregator IRQ domain
466	* @virq: Corresponding Linux virtual IRQ number
467	* @nr_irqs: Continuous irqs to be allocated
468	* @data: Pointer to firmware specifier
469	*
470	* No actual allocation happens here.
471	*
472	* Return 0 if all went well else appropriate error value.
473	*/
474	static int ti_sci_inta_irq_domain_alloc(struct irq_domain *domain,
475	unsigned int virq, unsigned int nr_irqs,
476	void *data)
477	{
478	msi_alloc_info_t *arg = data;
479
480	irq_domain_set_info(domain, virq, arg->hwirq, &ti_sci_inta_irq_chip,
481	NULL, handle_edge_irq, NULL, NULL);
482
483	return 0;
484	}
485
486	static const struct irq_domain_ops ti_sci_inta_irq_domain_ops = {
487	.free = ti_sci_inta_irq_domain_free,
488	.alloc = ti_sci_inta_irq_domain_alloc,
489	};
490
f011df61 LV	491	static struct irq_chip ti_sci_inta_msi_irq_chip = {
	492	.name = "MSI-INTA",
	493	.flags = IRQCHIP_SUPPORTS_LEVEL_MSI,
	494	};
	495
	496	static void ti_sci_inta_msi_set_desc(msi_alloc_info_t *arg,
	497	struct msi_desc *desc)
	498	{
	499	struct platform_device *pdev = to_platform_device(desc->dev);
	500
	501	arg->desc = desc;
	502	arg->hwirq = TO_HWIRQ(pdev->id, desc->inta.dev_index);
	503	}
	504
	505	static struct msi_domain_ops ti_sci_inta_msi_ops = {
	506	.set_desc = ti_sci_inta_msi_set_desc,
	507	};
	508
	509	static struct msi_domain_info ti_sci_inta_msi_domain_info = {
	510	.flags = (MSI_FLAG_USE_DEF_DOM_OPS \| MSI_FLAG_USE_DEF_CHIP_OPS \|
	511	MSI_FLAG_LEVEL_CAPABLE),
	512	.ops = &ti_sci_inta_msi_ops,
	513	.chip = &ti_sci_inta_msi_irq_chip,
	514	};
	515
9f1463b8 LV	516	static int ti_sci_inta_irq_domain_probe(struct platform_device *pdev)
9f1463b8 LV	517	{
f011df61	518	struct irq_domain parent_domain, domain, *msi_domain;
9f1463b8 LV	519	struct device_node parent_node, node;
	520	struct ti_sci_inta_irq_domain *inta;
	521	struct device *dev = &pdev->dev;
	522	struct resource *res;
	523	int ret;
	524
	525	node = dev_of_node(dev);
	526	parent_node = of_irq_find_parent(node);
	527	if (!parent_node) {
	528	dev_err(dev, "Failed to get IRQ parent node\n");
	529	return -ENODEV;
	530	}
	531
	532	parent_domain = irq_find_host(parent_node);
	533	if (!parent_domain)
	534	return -EPROBE_DEFER;
	535
	536	inta = devm_kzalloc(dev, sizeof(*inta), GFP_KERNEL);
	537	if (!inta)
	538	return -ENOMEM;
	539
	540	inta->pdev = pdev;
	541	inta->sci = devm_ti_sci_get_by_phandle(dev, "ti,sci");
	542	if (IS_ERR(inta->sci)) {
	543	ret = PTR_ERR(inta->sci);
	544	if (ret != -EPROBE_DEFER)
	545	dev_err(dev, "ti,sci read fail %d\n", ret);
	546	inta->sci = NULL;
	547	return ret;
	548	}
	549
	550	ret = of_property_read_u32(dev->of_node, "ti,sci-dev-id", &pdev->id);
	551	if (ret) {
	552	dev_err(dev, "missing 'ti,sci-dev-id' property\n");
	553	return -EINVAL;
	554	}
	555
	556	inta->vint = devm_ti_sci_get_of_resource(inta->sci, dev, pdev->id,
	557	"ti,sci-rm-range-vint");
	558	if (IS_ERR(inta->vint)) {
	559	dev_err(dev, "VINT resource allocation failed\n");
	560	return PTR_ERR(inta->vint);
	561	}
	562
	563	inta->global_event = devm_ti_sci_get_of_resource(inta->sci, dev, pdev->id,
	564	"ti,sci-rm-range-global-event");
	565	if (IS_ERR(inta->global_event)) {
	566	dev_err(dev, "Global event resource allocation failed\n");
	567	return PTR_ERR(inta->global_event);
	568	}
	569
	570	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	571	inta->base = devm_ioremap_resource(dev, res);
	572	if (IS_ERR(inta->base))
	573	return -ENODEV;
	574
	575	domain = irq_domain_add_linear(dev_of_node(dev),
	576	ti_sci_get_num_resources(inta->vint),
	577	&ti_sci_inta_irq_domain_ops, inta);
	578	if (!domain) {
	579	dev_err(dev, "Failed to allocate IRQ domain\n");
	580	return -ENOMEM;
	581	}
	582
f011df61 LV	583	msi_domain = ti_sci_inta_msi_create_irq_domain(of_node_to_fwnode(node),
	584	&ti_sci_inta_msi_domain_info,
	585	domain);
	586	if (!msi_domain) {
	587	irq_domain_remove(domain);
	588	dev_err(dev, "Failed to allocate msi domain\n");
	589	return -ENOMEM;
	590	}
	591
9f1463b8 LV	592	INIT_LIST_HEAD(&inta->vint_list);
	593	mutex_init(&inta->vint_mutex);
	594
	595	return 0;
	596	}
	597
	598	static const struct of_device_id ti_sci_inta_irq_domain_of_match[] = {
	599	{ .compatible = "ti,sci-inta", },
	600	{ /* sentinel */ },
	601	};
	602	MODULE_DEVICE_TABLE(of, ti_sci_inta_irq_domain_of_match);
	603
	604	static struct platform_driver ti_sci_inta_irq_domain_driver = {
	605	.probe = ti_sci_inta_irq_domain_probe,
	606	.driver = {
	607	.name = "ti-sci-inta",
	608	.of_match_table = ti_sci_inta_irq_domain_of_match,
	609	},
	610	};
	611	module_platform_driver(ti_sci_inta_irq_domain_driver);
	612
	613	MODULE_AUTHOR("Lokesh Vutla <lokeshvutla@ticom>");
	614	MODULE_DESCRIPTION("K3 Interrupt Aggregator driver over TI SCI protocol");
	615	MODULE_LICENSE("GPL v2");