/* $OpenBSD: prom_disp.s,v 1.7 2008/01/13 20:59:52 kettenis Exp $ */
/* $NetBSD: prom_disp.s,v 1.8 1997/11/03 04:22:03 ross Exp $ */

/*
 * Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University.
 * All rights reserved.
 *
 * Author: Chris G. Demetriou
 * 
 * Permission to use, copy, modify and distribute this software and
 * its documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 * 
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 
 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 * 
 * Carnegie Mellon requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 *
 * any improvements or extensions that they make and grant Carnegie the
 * rights to redistribute these changes.
 */

.file   2 __FILE__
.loc    2 __LINE__

#ifndef _LOCORE
#include <machine/asm.h>
#endif

        .globl  prom_dispatch_v
        .comm   prom_dispatch_v,16

        .text
        .align  4

/*
 * Dispatcher routine.  Implements prom's calling machinery, saves our
 * callee-saved registers as required by C.
 */
#define D_RA                     (7*8)
#define D_S0                     (8*8)
#define D_S1                     (9*8)
#define D_S2                    (10*8)
#define D_S3                    (11*8)
#define D_S4                    (12*8)
#define D_S5                    (13*8)
#define D_S6                    (14*8)
#define DISPATCH_FRAME_SIZE     (15*8)
#define DISPATCH_REGS           IM_RA|IM_S0|IM_S1|IM_S2|IM_S3|IM_S4|IM_S5|IM_S6

NESTED(prom_dispatch, 5, DISPATCH_FRAME_SIZE, ra, DISPATCH_REGS, 0)

        ldgp    gp, 0(pv)

        lda     sp, -DISPATCH_FRAME_SIZE(sp)
        stq     ra, D_RA(sp)
        stq     s0, D_S0(sp)
        stq     s1, D_S1(sp)
        stq     s2, D_S2(sp)
        stq     s3, D_S3(sp)
        stq     s4, D_S4(sp)
        stq     s5, D_S5(sp)
        stq     s6, D_S6(sp)

        /* Lord have mercy because.. I would not. */
#define STUPID_PROM_IS_32_BITS
#ifdef  STUPID_PROM_IS_32_BITS
        ldah    s0, 0x2000(zero)        /* hack for hack */
        lda     s0, (0x2000-8)(s0)

        stq     sp, 0(s0)
        or      s0, zero, sp
#endif  /* STUPID_PROM_IS_32_BITS */

        lda     pv, prom_dispatch_v
        ldq     v0, 0(pv)               /* routine */
        ldq     pv, 8(pv)               /* routine_arg */
        
        jsr     ra, (v0)

#ifdef  STUPID_PROM_IS_32_BITS
        ldah    s0, 0x2000(zero)        /* hack for hack */
        lda     s0, (0x2000-8)(s0)

        ldq     sp, 0(s0)
#endif  /* STUPID_PROM_IS_32_BITS */

        ldq     ra, D_RA(sp)
        ldq     s0, D_S0(sp)
        ldq     s1, D_S1(sp)
        ldq     s2, D_S2(sp)
        ldq     s3, D_S3(sp)
        ldq     s4, D_S4(sp)
        ldq     s5, D_S5(sp)
        ldq     s6, D_S6(sp)
        lda     sp, DISPATCH_FRAME_SIZE(sp)
        RET
END(prom_dispatch)

#undef  D_RA                    
#undef  D_S0                    
#undef  D_S1                    
#undef  D_S2                    
#undef  D_S3                    
#undef  D_S4                    
#undef  D_S5                    
#undef  D_S6                    
#undef  DISPATCH_FRAME_SIZE
#undef  DISPATCH_REGS