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/* set_vector
*
* This routine installs an interrupt vector under go32.
*
* INPUT:
* handler - interrupt handler entry point
* vector - vector number
* type - 0 indicates raw hardware connect
* 1 indicates RTEMS interrupt connect
*
* RETURNS:
* address of previous interrupt handler
*
* COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994.
* On-Line Applications Research Corporation (OAR).
* All rights assigned to U.S. Government, 1994.
*
* This material may be reproduced by or for the U.S. Government pursuant
* to the copyright license under the clause at DFARS 252.227-7013. This
* notice must appear in all copies of this file and its derivatives.
*
* $Id$
*/
#include <rtems.h>
#include <bsp.h>
#include <dpmi.h>
#include <go32.h>
i386_isr_entry set_vector( /* returns old vector */
rtems_isr_entry handler, /* isr routine */
rtems_vector_number vector, /* vector number */
int type /* RTEMS or RAW intr */
)
{
i386_isr_entry previous_isr;
if ( type ) {
rtems_interrupt_catch( handler, vector,
(rtems_isr_entry *) &previous_isr );
} else {
/* Interrupt goes straight to the supplied ISR. This code is */
/* slightly different than that in _CPU_ISR_install_vector */
/* (which is eventually called by the above) in that this code */
/* returns the raw entry point as the old handler, while the */
/* other version returns the old entry point pointed at by the */
/* rtems ISR table. */
_go32_dpmi_seginfo handler_info;
/* get the address of the old handler */
_go32_dpmi_get_protected_mode_interrupt_vector( vector, &handler_info);
/* Notice how we're failing to save the pm_segment portion of the */
/* structure here? That means we might crash the system if we */
/* try to restore the ISR. Can't fix this until i386_isr is */
/* redefined. XXX [BHC]. */
previous_isr = (i386_isr_entry) handler_info.pm_offset;
/* install the IDT entry */
handler_info.pm_offset = (u_long)handler;
handler_info.pm_selector = _go32_my_cs();
_go32_dpmi_set_protected_mode_interrupt_vector( vector, &handler_info);
}
return previous_isr;
}
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