/*
 * Copyright (c) 2006 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup genericddi
 * @{
 */
/** @file
 */

#ifndef KERN_IRQ_H_
#define KERN_IRQ_H_

#ifdef KERNEL

#include <typedefs.h>
#include <adt/list.h>
#include <adt/hash_table.h>
#include <synch/spinlock.h>
#include <proc/task.h>
#include <ipc/ipc.h>

#endif /* KERNEL */

typedef enum {
	/** Read 1 byte from the I/O space. */
	CMD_PIO_READ_8 = 1,
	/** Read 2 bytes from the I/O space. */
	CMD_PIO_READ_16,
	/** Read 4 bytes from the I/O space. */
	CMD_PIO_READ_32,
	
	/** Write 1 byte to the I/O space. */
	CMD_PIO_WRITE_8,
	/** Write 2 bytes to the I/O space. */
	CMD_PIO_WRITE_16,
	/** Write 4 bytes to the I/O space. */
	CMD_PIO_WRITE_32,
	
	/**
	 * Write 1 byte from the source argument
	 * to the I/O space.
	 */
	CMD_PIO_WRITE_A_8,
	/**
	 * Write 2 bytes from the source argument
	 * to the I/O space.
	 */
	CMD_PIO_WRITE_A_16,
	/**
	 * Write 4 bytes from the source argument
	 * to the I/O space.
	 */
	CMD_PIO_WRITE_A_32,
	
	/**
	 * Perform a bit masking on the source argument
	 * and store the result into the destination argument.
	 */
	CMD_BTEST,
	
	/**
	 * Predicate the execution of the following
	 * N commands by the boolean value of the source
	 * argument.
	 */
	CMD_PREDICATE,
	
	/** Accept the interrupt. */
	CMD_ACCEPT,
	
	/** Decline the interrupt. */
	CMD_DECLINE,
	CMD_LAST
} irq_cmd_type;

typedef struct {
	irq_cmd_type cmd;
	void *addr;
	uint32_t value;
	uintptr_t srcarg;
	uintptr_t dstarg;
} irq_cmd_t;

typedef struct {
	size_t cmdcount;
	irq_cmd_t *cmds;
} irq_code_t;

#ifdef KERNEL

typedef enum {
	IRQ_DECLINE,  /**< Decline to service. */
	IRQ_ACCEPT    /**< Accept to service. */
} irq_ownership_t;

typedef enum {
	IRQ_TRIGGER_LEVEL = 1,
	IRQ_TRIGGER_EDGE
} irq_trigger_t;

struct irq;
typedef void (* irq_handler_t)(struct irq *);

/** Type for function used to clear the interrupt. */
typedef void (* cir_t)(void *, inr_t);

/** IPC notification config structure.
 *
 * Primarily, this structure is encapsulated in the irq_t structure.
 * It is protected by irq_t::lock.
 *
 */
typedef struct {
	/** When false, notifications are not sent. */
	bool notify;
	/** Answerbox for notifications. */
	answerbox_t *answerbox;
	/** Interface and method to be used for the notification. */
	sysarg_t imethod;
	/** Arguments that will be sent if the IRQ is claimed. */
	uint32_t scratch[IPC_CALL_LEN];
	/** Top-half pseudocode. */
	irq_code_t *code;
	/** Counter. */
	size_t counter;
	
	/**
	 * Link between IRQs that are notifying the same answerbox. The list is
	 * protected by the answerbox irq_lock.
	 */
	link_t link;
} ipc_notif_cfg_t;

/** Structure representing one device IRQ.
 *
 * If one device has multiple interrupts, there will be multiple irq_t
 * instantions with the same devno.
 *
 */
typedef struct irq {
	/** Hash table link. */
	link_t link;
	
	/** Lock protecting everything in this structure
	 *  except the link member. When both the IRQ
	 *  hash table lock and this lock are to be acquired,
	 *  this lock must not be taken first.
	 */
	IRQ_SPINLOCK_DECLARE(lock);
	
	/** Send EOI before processing the interrupt.
	 *  This is essential for timer interrupt which
	 *  has to be acknowledged before doing preemption
	 *  to make sure another timer interrupt will
	 *  be eventually generated.
	 */
	bool preack;
	
	/** Unique device number. -1 if not yet assigned. */
	devno_t devno;
	
	/** Actual IRQ number. -1 if not yet assigned. */
	inr_t inr;
	/** Trigger level of the IRQ. */
	irq_trigger_t trigger;
	/** Claim ownership of the IRQ. */
	irq_ownership_t (* claim)(struct irq *);
	/** Handler for this IRQ and device. */
	irq_handler_t handler;
	/** Instance argument for the handler and the claim function. */
	void *instance;
	
	/** Clear interrupt routine. */
	cir_t cir;
	/** First argument to the clear interrupt routine. */
	void *cir_arg;
	
	/** Notification configuration structure. */
	ipc_notif_cfg_t notif_cfg; 
} irq_t;

IRQ_SPINLOCK_EXTERN(irq_uspace_hash_table_lock);
extern hash_table_t irq_uspace_hash_table;

extern inr_t last_inr;

extern void irq_init(size_t, size_t);
extern void irq_initialize(irq_t *);
extern void irq_register(irq_t *);
extern irq_t *irq_dispatch_and_lock(inr_t);

#endif /* KERNEL */

#endif

/** @}
 */