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/*

 * crt0.S -- startup file for hppa.

 *              rob@cygnus.com (Rob Savoye)

 */

        .VERSION "0.2"

        .COPYRIGHT "crt0.S for hppa"

;sp      .equ    %r30                   ; stack pointer

;dp      .equ    %r27                   ; global data pointer

;arg0    .equ    %r26                   ; argument

;arg1    .equ    %r25                   ; argument or high part of double argument

;arg2    .equ    %r24                   ; argument

;arg3    .equ    %r23                   ; argument or high part of double argument

#define         IMM(a,b)        ldil L%a,b  ! ldo  R%a(b),b

#define         imm(i,t)        ldil LS%i,t ! addi RS%i,t,t

        .DATA

/****

 * FIXME: these are just a gross hack so this will assemble

 ****/

_bss_start      .WORD

_bss_end        .WORD

_foobar

                .STRINGZ "Foo Bar...\r\n"

;;_SYSTEM_ID    .WORD

;;              .EXPORT _SYSTEM_ID      ; FIXME this is only so it'll

                                        ; link

/*

 * Set up the standard spaces (sections) These definitions come

 * from /lib/pcc_prefix.s.

 */

        .space  $TEXT$,0

        .SUBSPA $BOOT$,QUAD=0,ALIGN=8,ACCESS=0x2c,SORT=4

        .IMPORT _start

/*

 * stuff we need that's defined elsewhere.

 */

        .IMPORT main, CODE

        .IMPORT _bss_start, DATA

        .IMPORT _bss_end, DATA

        .IMPORT environ, DATA

/*

 * start -- set things up so the application will run.

 *

 */

        .PROC

        .CALLINFO SAVE_SP, FRAME=48

        .EXPORT $START$,ENTRY

$START$

        /* FIXME: this writes to page zero */

        ;; setup the %30 (stack pointer) with some memory

        ldil    L%_stack+48,%r30

        ldo     R%_stack+48(%r30),%r30          ; should be %r30 (sp) but then

                                                ; we'd kill our test program :-)

        ;; we need to set %r27 (global data pointer) here too 

        ldil    L%$global$,%r27

        ldo     R%$global$(%r27),%r27           ; same problem as above

/*

 * zerobss -- zero out the bss section

 */

        ; load the start of bss

        ldil    L%_bss_start,%r4

        ldo     R%_bss_start(%r4),%r4

        ;  load the end of bss

        ldil    L%_bss_end,%r5

        ldo     R%_bss_end(%r5),%r5

bssloop

        addi    -1,%r5,%r5                      ; decrement _bss_end

        stb     %r0,0(0,%r5)                      ; we do this by bytes for now even

                                                ; though it's slower, it's safer

        combf,= %r4,%r5, bssloop

        nop

        ldi     1,%ret0

/*

 * Call the main routine from the application to get it going.

 * main (argc, argv, environ)

 * We pass argv as a pointer to NULL.

 */

        bl      main,%r2

        nop

        .PROCEND

/*

 * _exit -- Exit from the application. Normally we cause a user trap

 *          to return to the ROM monitor for another run, but with

 *          this monitor we can't. Still, "C" wants this symbol, it

 *          should be here. Jumping to 0xF0000004 jumps back into the

 *          firmware, while writing a 5 to 0xFFFE0030 causes a reset.

 */

        .EXPORT _exit, ENTRY

_exit

        .PROC

        .CALLINFO

        .ENTRY

;;      ldil    L%0xf0000004,%r1

;;      bl      %r1, %r2

        ldil    L'4026531844,%r19

        ldo     R'4026531844(%r19),%r19

        blr     %r19, %r2

        nop

        ;; This just causes a breakpoint exception

;;      break   0x0e,0xa5a

;;      bv,n    (%rp)

        nop

        .EXIT

        .PROCEND

        .subspa $UNWIND_START$,QUAD=0,ALIGN=8,ACCESS=0x2c,SORT=56

        .export $UNWIND_START

$UNWIND_START

        .subspa $UNWIND$,QUAD=0,ALIGN=8,ACCESS=0x2c,SORT=64

        .subspa $UNWIND_END$,QUAD=0,ALIGN=8,ACCESS=0x2c,SORT=72

        .export $UNWIND_END

$UNWIND_END

        .subspa $RECOVER_START$,QUAD=0,ALIGN=4,ACCESS=0x2c,SORT=73

        .export $RECOVER_START

$RECOVER_START

        .subspa $RECOVER$,QUAD=0,ALIGN=4,ACCESS=0x2c,SORT=80

        .subspa $RECOVER_END$,QUAD=0,ALIGN=4,ACCESS=0x2c,SORT=88

        .export $RECOVER_END

$RECOVER_END

; The following declarations are, by default in the data space ($PRIVATE$)

;;        .space  $PRIVATE$,1

/*

 * Here we set up the standard date sub spaces.

 * _dp is for the WinBond board.

 *

 * Set up some room for a stack. We just grab a chunk of memory.

 * We also setup some space for the global variable space, which

 * must be done using the reserved name "$global$" so "C" code

 * can find it. The stack grows towards the higher addresses.

 */

        .subspa $DATA$,QUAD=1,ALIGN=8,ACCESS=0x1f,SORT=16

        .subspa $SHORTDATA$,QUAD=1,ALIGN=8,ACCESS=0x1f,SORT=24

        .subspa $GLOBAL$,QUAD=1,ALIGN=8,ACCESS=0x1f,SORT=40

        .export $global$

        .export _dp

$global$

_dp

        .subspa $SHORTBSS$,QUAD=1,ALIGN=8,ACCESS=0x1f,SORT=80,ZERO

        .subspa $BSS$,QUAD=1,ALIGN=8,ACCESS=0x1f,SORT=82,ZERO

       .subspa $STACK$,QUAD=1,ALIGN=8,ACCESS=0x1f,SORT=88,ZERO

        .export _stack

_stack

        .BLOCK          0x2000

/*

 * The heap follows the stack. To use dynamic memory routines in an

 * application, some space MUST be assigned to the stack.

 */

        .subspa $HEAP$,QUAD=1,ALIGN=8,ACCESS=0x1f,SORT=96,ZERO

        .export _heap

_heap

        .end