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/*

 *  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 

#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 */