/**
* @file irq.h
*
* This include file describe the data structure and the functions implemented
* by rtems to write interrupt handlers.
*/
/*
* RTEMS GBA BSP
*
* Copyright (c) 2004 Markku Puro <markku.puro@kopteri.net>
*
* The license and distribution terms for this file may be
* found in found in the file LICENSE in this distribution or at
* http://www.rtems.com/license/LICENSE.
*
* $Id$
*/
#ifndef _IRQ_H_
#define _IRQ_H_
#ifdef __cplusplus
extern "C" {
#endif
/*
* Include some preprocessor value also used by assember code
*/
#define VECTOR_TABLE (&irq_vector_table[0])
#include <stdint.h>
#include <rtems.h>
extern void default_int_handler();
/*---------------------------------------------------------------------------*
* MACROS *
*---------------------------------------------------------------------------*/
#define ENABLE_IRQ() GBA_REG_IME = 1;
#define DISABLE_IRQ() GBA_REG_IME = 0;
/*-------------------------------------------------------------------------+
| Constants
+--------------------------------------------------------------------------*/
typedef enum {
BSP_IRQ_VBLANK = 0,
BSP_IRQ_HBLANK = 1,
BSP_IRQ_VCOUNTER = 2,
BSP_IRQ_TIMER0 = 3,
BSP_IRQ_TIMER1 = 4,
BSP_IRQ_TIMER2 = 5,
BSP_IRQ_TIMER3 = 6,
BSP_IRQ_SERIAL = 7,
BSP_IRQ_DMA0 = 8,
BSP_IRQ_DMA1 = 9,
BSP_IRQ_DMA2 = 10,
BSP_IRQ_DMA3 = 11,
BSP_IRQ_KEY = 12,
BSP_IRQ_CART = 13,
BSP_IRQ_NA14 = 14,
BSP_IRQ_NA15 = 15,
BSP_MAX_INT = 16 /**< BSP_MAX_INT <= _irq_max_vector in linkcmds */
} rtems_irq_symbolic_name;
/*
* Type definition for RTEMS managed interrupts
*/
typedef unsigned char rtems_irq_level;
typedef unsigned char rtems_irq_trigger;
extern void _irq_max_vector; /**< defined in lincmds */
extern uint32_t irq_vector_table[BSP_MAX_INT]; /**< allocated in linkcmds */
struct __rtems_irq_connect_data__; /* forward declaratiuon */
typedef void (*rtems_irq_hdl) (void);
typedef void (*rtems_irq_enable) (const struct __rtems_irq_connect_data__*);
typedef void (*rtems_irq_disable) (const struct __rtems_irq_connect_data__*);
typedef int (*rtems_irq_is_enabled) (const struct __rtems_irq_connect_data__*);
/** irq connection data structure */
typedef struct __rtems_irq_connect_data__ {
/**
* IRQ line
*/
rtems_irq_symbolic_name name;
/**
* handler. See comment on handler properties below in function prototype.
*/
rtems_irq_hdl hdl;
/**
* function for enabling interrupts at device level (ONLY!).
* The BSP code will automatically enable it at PIC level.
* RATIONALE : anyway such code has to exist in current driver code.
* It is usually called immediately AFTER connecting the interrupt handler.
* RTEMS may well need such a function when restoring normal interrupt
* processing after a debug session.
*
*/
rtems_irq_enable on;
/**
* function for disabling interrupts at device level (ONLY!).
* The code will disable it at PIC level. RATIONALE : anyway
* such code has to exist for clean shutdown. It is usually called
* BEFORE disconnecting the interrupt. RTEMS may well need such
* a function when disabling normal interrupt processing for
* a debug session. May well be a NOP function.
*/
rtems_irq_disable off;
/**
* function enabling to know what interrupt may currently occur
* if someone manipulates the PIC interrupt mask without care...
*/
rtems_irq_is_enabled isOn;
/**
* irq priority level
*/
rtems_irq_level irqLevel;
/**
* Trigger way : Rising or falling edge or High or low level
*/
rtems_irq_trigger irqTrigger;
} rtems_irq_connect_data;
/*-------------------------------------------------------------------------+
| Function Prototypes.
+--------------------------------------------------------------------------*/
/*
* ------------------------ RTEMS Single Irq Handler Mngt Routines ----------------
*/
/**
* @brief function to initialize the interrupt for a specific BSP
*/
void BSP_rtems_irq_mngt_init();
/**
* @brief function to connect a particular irq handler.
* This hanlder will NOT be called directly as the result of the corresponding interrupt.
* Instead, a RTEMS irq prologue will be called that will :
* 1) save the C scratch registers,
* 2) switch to a interrupt stack if the interrupt is not nested,
* 3) store the current i8259s' interrupt masks
* 4) modify them to disable the current interrupt at 8259 level (and may
* be others depending on software priorities)
* 5) aknowledge the i8259s',
* 6) demask the processor,
* 7) call the application handler
*
* As a result the hdl function provided
* a) can perfectly be written is C,
* b) may also well directly call the part of the RTEMS API that can be used
* from interrupt level,
* c) It only responsible for handling the jobs that need to be done at
* the device level including (aknowledging/re-enabling the interrupt at device,
* level, getting the data,...)
*
* When returning from the function, the following will be performed by
* the RTEMS irq epilogue :
*
* 1) masks the interrupts again,
* 2) restore the original i8259s' interrupt masks
* 3) switch back on the orinal stack if needed,
* 4) perform rescheduling when necessary,
* 5) restore the C scratch registers...
* 6) restore initial execution flow
*
*/
int BSP_install_rtems_irq_handler (const rtems_irq_connect_data*);
/**
* function to get the current RTEMS irq handler for ptr->name. It enables to
* define hanlder chain...
*/
int BSP_get_current_rtems_irq_handler (rtems_irq_connect_data* ptr);
/**
* @brief function to get disconnect the RTEMS irq handler for ptr->name.
* This function checks that the value given is the current one for safety reason.
* The user can use the previous function to get it.
*/
int BSP_remove_rtems_irq_handler (const rtems_irq_connect_data*);
#ifdef __cplusplus
}
#endif
#endif /* _IRQ_H_ */
