/* SPDX-License-Identifier: BSD-2-Clause */
/*
 * Copyright (c) 2016-2019, Linaro Limited
 */
#ifndef __KERNEL_INTERRUPT_H
#define __KERNEL_INTERRUPT_H

#include <dt-bindings/interrupt-controller/irq.h>
#include <mm/core_memprot.h>
#include <sys/queue.h>
#include <tee_api_types.h>
#include <types_ext.h>
#include <util.h>

#define ITRF_TRIGGER_LEVEL	BIT(0)
#define ITRF_SHARED		BIT(1)

struct itr_handler;

/*
 * struct itr_chip - Interrupt controller
 *
 * @ops Operation callback functions
 * @name Controller name, for debug purpose
 * @handlers Registered handlers list head
 * @dt_get_irq Device tree node parsing function
 */
struct itr_chip {
	const struct itr_ops *ops;
	const char *name;
	SLIST_HEAD(, itr_handler) handlers;
	/*
	 * dt_get_irq - parse a device tree interrupt property
	 *
	 * @properties raw interrupt property from device tree
	 * @count number of elements in @properties
	 * @type If not NULL, output interrupt type (IRQ_TYPE_* defines)
	 * or IRQ_TYPE_NONE if unknown
	 * @prio If not NULL, output interrupt priority value or 0 if unknown
	 */
	int (*dt_get_irq)(const uint32_t *properties, int count, uint32_t *type,
			  uint32_t *prio);
};

/*
 * struct itr_ops - Interrupt controller operations
 * @add		Register and configure an interrupt
 * @enable	Enable an interrupt
 * @disable	Disable an interrupt
 * @mask	Mask an interrupt, may be called from an interrupt context
 * @unmask	Unmask an interrupt, may be called from an interrupt context
 * @raise_pi	Raise per-cpu interrupt or NULL if not applicable
 * @raise_sgi	Raise a SGI or NULL if not applicable to that controller
 * @set_affinity Set interrupt/cpu affinity or NULL if not applicable
 *
 * Handlers @enable, @disable, @mask, @unmask and @add are mandated. Handlers
 * @mask and @unmask have unpaged memory contrainsts. See itr_chip_is_valid().
 */
struct itr_ops {
	void (*add)(struct itr_chip *chip, size_t it, uint32_t type,
		    uint32_t prio);
	void (*enable)(struct itr_chip *chip, size_t it);
	void (*disable)(struct itr_chip *chip, size_t it);
	void (*mask)(struct itr_chip *chip, size_t it);
	void (*unmask)(struct itr_chip *chip, size_t it);
	void (*raise_pi)(struct itr_chip *chip, size_t it);
	void (*raise_sgi)(struct itr_chip *chip, size_t it,
		uint8_t cpu_mask);
	void (*set_affinity)(struct itr_chip *chip, size_t it,
		uint8_t cpu_mask);
};

/* Interrupt handler return value */
enum itr_return {
	ITRR_NONE,
	ITRR_HANDLED,
};

/* Interrupt handler signature */
typedef enum itr_return (*itr_handler_t)(struct itr_handler *h);

/*
 * struct itr_handler - Interrupt handler reference
 * @it Interrupt number
 * @flags Property bit flags (ITRF_*) or 0
 * @data Private data for that interrupt handler
 * @chip Interrupt controller chip device
 * @link Reference in controller handler list
 */
struct itr_handler {
	size_t it;
	uint32_t flags;
	itr_handler_t handler;
	void *data;
	struct itr_chip *chip;
	SLIST_ENTRY(itr_handler) link;
};

#define ITR_HANDLER(_chip, _itr_num, _flags, _fn, _priv) \
	((struct itr_handler){ \
		.chip = (_chip), .it = (_itr_num), .flags = (_flags), \
		.handler = (_fn), .data = (_priv), \
	})

/*
 * Return true only if interrupt chip provides required handlers
 * @chip: Interrupt controller reference
 */
static inline bool itr_chip_is_valid(struct itr_chip *chip)
{
	return chip && is_unpaged(chip) && chip->ops &&
	       is_unpaged((void *)chip->ops) &&
	       chip->ops->mask && is_unpaged(chip->ops->mask) &&
	       chip->ops->unmask && is_unpaged(chip->ops->unmask) &&
	       chip->ops->enable && chip->ops->disable &&
	       chip->ops->add;
}

/*
 * Initialise an interrupt controller handle
 * @chip	Interrupt controller
 */
TEE_Result itr_chip_init(struct itr_chip *chip);

/*
 * Initialise main interrupt controller driver
 * @data Main controller main data reference to register
 */
void interrupt_main_init(struct itr_chip *data);

/*
 * Call handlers registered for that interrupt in core interrupt controller
 * @it Interrupt line number
 */
void itr_handle(size_t it);

/* Retrieve main interrupt controller reference */
struct itr_chip *interrupt_get_main_chip(void);

#ifdef CFG_DT
/*
 * Get the DT interrupt property at @node. In the DT an interrupt property can
 * specify additional information which can be retrieved with @type and @prio.
 *
 * @fdt reference to the Device Tree
 * @node is the node offset to read the interrupt property from
 * @type interrupt type (IRQ_TYPE_* defines) if specified by interrupt property
 * or IRQ_TYPE_NONE if not. Can be NULL if not needed
 * @prio interrupt priority if specified by interrupt property or 0 if not. Can
 * be NULL if not needed
 *
 * Returns the interrupt number if value >= 0
 * otherwise DT_INFO_INVALID_INTERRUPT
 */
int dt_get_irq_type_prio(const void *fdt, int node, uint32_t *type,
			 uint32_t *prio);

/*
 * Get the DT interrupt property at @node
 */
static inline int dt_get_irq(const void *fdt, int node)
{
	return dt_get_irq_type_prio(fdt, node, NULL, NULL);
}
#endif

struct itr_handler *itr_alloc_add_type_prio(size_t it, itr_handler_t handler,
					    uint32_t flags, void *data,
					    uint32_t type, uint32_t prio);
void itr_free(struct itr_handler *hdl);
void itr_add_type_prio(struct itr_handler *handler, uint32_t type,
		       uint32_t prio);
void itr_enable(size_t it);
void itr_disable(size_t it);
/* raise the Peripheral Interrupt corresponding to the interrupt ID */
void itr_raise_pi(size_t it);
/*
 * raise the Software Generated Interrupt corresponding to the interrupt ID,
 * the cpu_mask represents which cpu interface to forward.
 */
void itr_raise_sgi(size_t it, uint8_t cpu_mask);
/*
 * let corresponding interrupt forward to the cpu interface
 * according to the cpu_mask.
 */
void itr_set_affinity(size_t it, uint8_t cpu_mask);

/*
 * __weak overridable function which is called when a secure interrupt is
 * received. The default function calls panic() immediately, platforms which
 * expects to receive secure interrupts should override this function.
 */
void interrupt_main_handler(void);

static inline void itr_add(struct itr_handler *handler)
{
	itr_add_type_prio(handler, IRQ_TYPE_NONE, 0);
}

static inline struct itr_handler *itr_alloc_add(size_t it,
						itr_handler_t handler,
						uint32_t flags, void *data)
{
	return itr_alloc_add_type_prio(it, handler, flags, data, IRQ_TYPE_NONE,
				       0);
}

/*
 * Interrupt controller chip API functions
 */

/*
 * interrupt_call_handlers() - Call registered handlers for an interrupt
 * @chip	Interrupt controller
 * @itr_num	Interrupt number
 *
 * This function is called from an interrupt context by a primary interrupt
 * handler. This function calls the handlers registered for that interrupt.
 * If interrupt is not handled, it is masked.
 */
void interrupt_call_handlers(struct itr_chip *chip, size_t itr_num);

/*
 * interrupt_mask() - Mask an interrupt
 * @chip	Interrupt controller
 * @itr_num	Interrupt number
 *
 * This function may be called in interrupt context
 */
static inline void interrupt_mask(struct itr_chip *chip, size_t itr_num)
{
	chip->ops->mask(chip, itr_num);
}

/*
 * interrupt_unmask() - Unmask an interrupt
 * @chip	Interrupt controller
 * @itr_num	Interrupt number
 *
 * This function may be called in interrupt context
 */
static inline void interrupt_unmask(struct itr_chip *chip, size_t itr_num)
{
	chip->ops->unmask(chip, itr_num);
}

/*
 * interrupt_enable() - Enable an interrupt
 * @chip	Interrupt controller
 * @itr_num	Interrupt number
 */
static inline void interrupt_enable(struct itr_chip *chip, size_t itr_num)
{
	chip->ops->enable(chip, itr_num);
}

/*
 * interrupt_disable() - Disable an interrupt
 * @chip	Interrupt controller
 * @itr_num	Interrupt number
 */
static inline void interrupt_disable(struct itr_chip *chip, size_t itr_num)
{
	chip->ops->disable(chip, itr_num);
}

/*
 * interrupt_configure() - Configure an interrupt in an interrupt controller
 * @chip	Interrupt controller
 * @itr_num	Interrupt number
 * @type	Interrupt trigger type (IRQ_TYPE_* defines) or IRQ_TYPE_NONE
 * @prio	Interrupt priority or 0
 *
 * Interrupt consumers that get their interrupt from the DT do not need to
 * call interrupt_configure() since the interrupt configuration has already
 * been done by interrupt controller based on the DT bidings.
 */
TEE_Result interrupt_configure(struct itr_chip *chip, size_t itr_num,
			       uint32_t type, uint32_t prio);

/*
 * interrupt_add_and_configure_handler() - Register and configure a handler
 * @hdl		Interrupt handler to register
 * @type	Interrupt trigger type (IRQ_TYPE_* defines) or IRQ_TYPE_NONE
 * @prio	Interrupt priority or 0
 */
TEE_Result interrupt_add_configure_handler(struct itr_handler *hdl,
					   uint32_t type, uint32_t prio);

/*
 * interrupt_add_handler() - Register an interrupt handler
 * @hdl		Interrupt handler to register
 *
 * This helper function assumes interrupt type is set to IRQ_TYPE_NONE
 * and interrupt priority to 0.
 */
static inline TEE_Result interrupt_add_handler(struct itr_handler *hdl)
{
	return interrupt_add_configure_handler(hdl, IRQ_TYPE_NONE, 0);
}

/*
 * interrupt_add_handler_with_chip() - Register an interrupt handler providing
 *	the interrupt chip reference in specific argument @chip.
 * @chip	Interrupt controller
 * @h		Interrupt handler to register
 */
static inline TEE_Result interrupt_add_handler_with_chip(struct itr_chip *chip,
							 struct itr_handler *h)
{
	h->chip = chip;
	return interrupt_add_handler(h);
}

/*
 * interrupt_remove_handler() - Remove a registered interrupt handler
 * @hdl		Interrupt handler to remove
 *
 * This function is the counterpart of interrupt_add_handler().
 * This function may panic on non-NULL invalid @hdl reference.
 */
void interrupt_remove_handler(struct itr_handler *hdl);

/*
 * interrupt_alloc_add_handler() - Allocate and register an interrupt handler
 * @chip	Interrupt controller
 * @itr_num	Interrupt number
 * @handler	Interrupt handler to register
 * @flags	Bitmask flag ITRF_*
 * @data	Private data reference passed to @handler
 * @out_hdl	NULL or output pointer to allocated struct itr_handler
 */
TEE_Result interrupt_alloc_add_handler(struct itr_chip *chip, size_t it_num,
				       itr_handler_t handler, uint32_t flags,
				       void *data,
				       struct itr_handler **out_hdl);

/*
 * interrupt_remove_free_handler() - Remove/free a registered interrupt handler
 * @hdl		Interrupt handler to remove and free
 *
 * This function is the counterpart of interrupt_alloc_add_handler().
 * This function may panic on non-NULL invalid @hdl reference.
 */
void interrupt_remove_free_handler(struct itr_handler *hdl);
#endif /*__KERNEL_INTERRUPT_H*/
