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/*=============================================================================

//

//      hal_cygm.S

//

//      SPARClite and CygMon play nice: vector service routines

//

//=============================================================================

// ####ECOSGPLCOPYRIGHTBEGIN####

// -------------------------------------------

// This file is part of eCos, the Embedded Configurable Operating System.

// Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.

//

// eCos is free software; you can redistribute it and/or modify it under

// the terms of the GNU General Public License as published by the Free

// Software Foundation; either version 2 or (at your option) any later

// version.

//

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// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

// for more details.

//

// You should have received a copy of the GNU General Public License

// along with eCos; if not, write to the Free Software Foundation, Inc.,

// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

//

// As a special exception, if other files instantiate templates or use

// macros or inline functions from this file, or you compile this file

// and link it with other works to produce a work based on this file,

// this file does not by itself cause the resulting work to be covered by

// the GNU General Public License. However the source code for this file

// must still be made available in accordance with section (3) of the GNU

// General Public License v2.

//

// This exception does not invalidate any other reasons why a work based

// on this file might be covered by the GNU General Public License.

// -------------------------------------------

// ####ECOSGPLCOPYRIGHTEND####

//=============================================================================

//#####DESCRIPTIONBEGIN####

//

// Author(s):   hmt

// Contributors:hmt

// Date:        1998-02-24

// Purpose:     SPARClite vectors for interworking with CygMon

// Description: see vectors.S and hal_priv.c; these VSRs are installed to

//              interwork with CygMon.

//

//####DESCRIPTIONEND####

//

//===========================================================================*/

!-----------------------------------------------------------------------------

//      .file   "hal_cygm.S"

!-----------------------------------------------------------------------------

#include 

#include 

#include 

#include 

!------------------------------------------------------------------------

#include        // eCos vector number et al

#include        // CygMon vector number et al

#define DELAYS_AFTER_WRPSR_SAME_WINDOW

#define DELAYS_AFTER_WRWIM

!------------------------------------------------------------------------

        .text

!---------------------------------------------------------------------------

#ifdef CYG_HAL_USE_ROM_MONITOR_CYGMON

        .global hal_user_trap_to_cygmon_vsr

hal_user_trap_to_cygmon_vsr:

        ! here,locals have been set up as follows:

        ! %l0 = psr (with this CWP/window-level in it)

        ! %l1 = pc

        ! %l2 = npc

        ! %l3 = vector number (1-15 for interrupts)

        ! and we are in our own register window, though it is likely that

        ! the next one will need to be saved before we can use it:

        ! ie. this one is the invalid register window.

        rd      %tbr, %l4               ! Get the trap type

        srl     %l4, 4, %l4             ! into the bottom byte

        and     %l4, 0xff, %l4          ! actual trap number

        ! we deal with traps 1,3,8(+128) and 255 here.

        ! ta 1  => tt 129       :       breakpoint

        ! ta 3  => tt 131       :       flush windows (unneccessary, JIC)

        ! ta 8  => tt 136       :       syscall (apparently)

        ! ta 127 -OR- Debug Support Unit trap

        !       => tt 255       :       debug trap

        ! others bounce through to eCos handler, of course.

        cmp     %l4, 129

        beq     bounce_to_cygmon

        mov     BSP_EXC_BREAK, %l5

        ! ta 2 is a "skipped" breakpoint, we increment the PC, NPC

        ! ourselves to permit continuation.

        cmp     %l4, 130

        bne     1f

        nop

        mov     %l2, %l1

        add     %l2, 4, %l2

        b       bounce_to_cygmon

        mov     BSP_EXC_BREAK, %l5

1:

        cmp     %l4, 131

        beq     bounce_to_cygmon

        mov     BSP_EXC_WINFLUSH, %l5

        cmp     %l4, 136

        beq     bounce_to_cygmon

        mov     BSP_EXC_SYSCALL, %l5

        cmp     %l4, 255

        beq     bounce_to_cygmon

        mov     BSP_EXC_DEBUG, %l5

        ! if we are here, it~s not a recognized trap to feed to CygMon, so

        ! call the eCos default trap VSR:

        .extern hal_default_exception_vsr

        ba      hal_default_exception_vsr       ! should be in range

        nop                                     ! does not return

        .global hal_nofpcp_trap_to_cygmon_vsr

hal_nofpcp_trap_to_cygmon_vsr:

        rd      %tbr, %l4               ! Get the trap type

        srl     %l4, 4, %l4             ! into the bottom byte

        and     %l4, 0xff, %l4          ! actual trap number

        ! we deal with trap types 4 and 36 here.

        cmp     %l4, 4

        beq     bounce_to_cygmon

        mov     BSP_EXC_FPDIS, %l5

        cmp     %l4, 36

        beq     bounce_to_cygmon

        mov     BSP_EXC_CPDIS, %l5

        ! we really should not be here otherwise, but for best debugging...

        b       bounce_to_cygmon

        mov     BSP_EXC_TRAP, %l5

bounce_to_cygmon:

        ! here we have decided to jump over CygMon, the CygMon vector

        ! number to use is in %l5.

        set     CYGMON_VECTOR_TABLE_BASE, %l6

        sll     %l5, 2, %l5             ! to a word offset

        ! our calling convention is the same, so...

        ld      [ %l6 + %l5 ], %l6

        jmp     %l6

        nop

// Now a handler for INT15 (NMI) to assist in debugging; we have to ack and

// clear the interrupt, after waiting for the source to go away, I guess...

        .global hal_nmi_handler

hal_nmi_handler:

        ! here,locals have been set up as follows:

        ! %l0 = psr (with this CWP/window-level in it)

        ! %l1 = pc

        ! %l2 = npc

        ! %l3 = vector number (1-15 for interrupts)

        ! and we are in our own register window, though it is likely that

        ! the next one will need to be saved before we can use it:

        ! ie. this one is the invalid register window.

#define TRGM0   0

#define TRGM1   4

#define REQSNS  8

#define REQCLR 12

#define IMASK  16

#define IRLAT  20

#define IMODE  24

#define NMIBIT 0x80000000

        sethi   %hi( 0x10000000 ), %l4  ! base address of the 86940 companion

10:

        add     %l4, REQCLR, %l5        ! Request clear register

        set     NMIBIT, %l6

        sta     %l6, [ %l5 ] 4          ! Clear INT15

        add     %l4, REQSNS, %l5        ! Request sense register

        lda     [ %l5 ] 4, %l7

        andcc   %l6, %l7, %g0           ! test the sense bit

        sethi   %hi( 0x02000000 ), %l6  ! Pump it out to the LED

        srl     %l7, 24, %l7

        stb     %l7, [ %l6 + 3 ]

        bne     10b                     ! poll until the request is gone

        nop

        nop

        nop

        set     0x00100000, %l6         ! clear the latch

        add     %l4, IRLAT, %l5

        sta     %l6, [ %l5 ] 4

        nop

        nop

        nop

        b       bounce_to_cygmon

        mov     BSP_EXC_INT15, %l5

#endif // CYG_HAL_USE_ROM_MONITOR_CYGMON

! end of hal_cygm.S