/*
* systrap.S
*
* This file contains emulated system calls using software trap 0.
* The following calls are supported:
*
* + SYS_exit (halt)
* + SYS_irqdis (disable interrupts)
* + SYS_irqset (set interrupt level)
*
* COPYRIGHT:
*
* COPYRIGHT (c) 1995. European Space Agency.
*
* This terms of the RTEMS license apply to this file.
*
*/
#include <asm.h>
#include "syscall.h"
.seg "text"
/*
* system call
*
* On entry:
*
* l0 = psr (from trap table)
* l1 = pc
* l2 = npc
* g1 = system call id
*/
PUBLIC(syscall)
SYM(syscall):
subcc %g1, 2, %g0 ! syscall 2, disable interrupts
bne 3f
or %l0, 0x0f00, %l4 ! set PIL=15
mov %l4, %psr
or %l0, SPARC_PSR_ET_MASK, %i0 ! return old psr with ET=1
ba,a 9f
3:
subcc %g1, 3, %g0 ! syscall 3, enable interrupts
bne 1f
and %i0, SPARC_PSR_PIL_MASK, %l4
andn %l0, SPARC_PSR_PIL_MASK, %l5
or %l5, %l4, %l4
mov %l4, %psr
ba,a 9f
1:
ta 0 ! halt
9: ! leave
mov 0, %g1 ! clear %g1
jmpl %l2, %g0
rett %l2 + 4
PUBLIC(sparc_disable_interrupts)
SYM(sparc_disable_interrupts):
mov SYS_irqdis, %g1
ta 0
retl
nop
PUBLIC(sparc_enable_interrupts)
SYM(sparc_enable_interrupts):
mov SYS_irqen, %g1
ta 0
retl
nop
/* end of file */
