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/**
* @file rtems/irq.h
*
* This include file describe the data structure and the functions implemented
* by rtems to write interrupt handlers.
*/
/*
* CopyRight (C) 1998 valette@crf.canon.fr
*
* This code is heavilly inspired by the public specification of STREAM V2
* that can be found at :
*
* <http://www.chorus.com/Documentation/index.html> by following
* the STREAM API Specification Document link.
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#ifndef _RTEMS_IRQ_H
#define _RTEMS_IRQ_H
#ifndef ASM
#ifdef __cplusplus
extern "C" {
#endif
/*
* Type definition for RTEMS managed interrupts
*/
typedef unsigned char rtems_irq_prio;
struct __rtems_irq_connect_data__; /* forward declaratiuon */
typedef unsigned int rtems_irq_number;
typedef void *rtems_irq_hdl_param;
typedef void (*rtems_irq_hdl) (rtems_irq_hdl_param);
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__*);
typedef struct __rtems_irq_connect_data__ {
/*
* IRQ line
*/
rtems_irq_number name;
/*
* handler. See comment on handler properties below in function prototype.
*/
rtems_irq_hdl hdl;
/*
* Handler handle to store private data
*/
rtems_irq_hdl_param handle;
/*
* function for enabling interrupts at device level (ONLY!).
* The BSP code will automatically enable it at i8259s 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 i8259s 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 i8259s interrupt mask without care...
*/
rtems_irq_is_enabled isOn;
#ifdef BSP_SHARED_HANDLER_SUPPORT
/*
* Set to -1 for vectors forced to have only 1 handler
*/
void *next_handler;
#endif
} rtems_irq_connect_data;
typedef struct {
/*
* size of all the table fields (*Tbl) described below.
*/
unsigned int irqNb;
/*
* Default handler used when disconnecting interrupts.
*/
rtems_irq_connect_data defaultEntry;
/*
* Table containing initials/current value.
*/
rtems_irq_connect_data* irqHdlTbl;
/*
* actual value of BSP_ISA_IRQ_VECTOR_BASE...
*/
rtems_irq_number irqBase;
/*
* software priorities associated with interrupts.
* if (*irqPrio [i] > intrPrio [j] it means that
* interrupt handler hdl connected for interrupt name i
* will not be interrupted by the handler connected for interrupt j
* The interrupt source will be physically masked at i8259 level.
*/
rtems_irq_prio* irqPrioTbl;
} rtems_irq_global_settings;
/*-------------------------------------------------------------------------+
| Function Prototypes.
+--------------------------------------------------------------------------*/
/*
* -------------------- RTEMS Single Irq Handler Mngt Routines ----------------
*/
/*
* 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);
/*
* 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*);
/*
* ----------------- RTEMS Shared Irq Handler Mngt Routines ----------------
*/
#ifdef BSP_SHARED_HANDLER_SUPPORT
int BSP_install_rtems_shared_irq_handler (const rtems_irq_connect_data*);
#endif
/*
* Less cumbersome, alternate entry points;
* RETURNS: more traditional, 0 on success, nonzero on error
*
* The BSP_rtems_int_connect() and BSP_rtems_int_disconnect() functions are
* only present on some PowerPC BSPs. Do not use them. Use
* rtems_interrupt_handler_install() instead.
*/
int BSP_rtems_int_connect(
rtems_irq_number n,
rtems_irq_hdl hdl,
rtems_irq_hdl_param p
);
int BSP_rtems_int_disconnect(
rtems_irq_number n,
rtems_irq_hdl hdl,
rtems_irq_hdl_param p
);
/*
* ----------------- RTEMS Global Irq Handler Mngt Routines ----------------
*/
/*
* (Re) Initialize the RTEMS interrupt management.
*
* The result of calling this function will be the same as if each individual
* handler (config->irqHdlTbl[i].hdl) different from "config->defaultEntry.hdl"
* has been individualy connected via
* BSP_install_rtems_irq_handler(&config->irqHdlTbl[i])
* And each handler currently equal to config->defaultEntry.hdl
* has been previously disconnected via
* BSP_remove_rtems_irq_handler (&config->irqHdlTbl[i])
*
* This is to say that all information given will be used and not just
* only the space.
*
* CAUTION : the various table address contained in config will be used
* directly by the interrupt mangement code in order to save
* data size so they must stay valid after the call => they should
* not be modified or declared on a stack.
*/
int BSP_rtems_irq_mngt_set(rtems_irq_global_settings* config);
/*
* (Re) get info on current RTEMS interrupt management.
*/
int BSP_rtems_irq_mngt_get(rtems_irq_global_settings**);
#ifdef __cplusplus
}
#endif
#endif /* ASM */
#endif /* _RTEMS_IRQ_H */
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