xref: /openbsd/sys/arch/alpha/alpha/prom_disp.s (revision 3f3274e8)
1/* $OpenBSD: prom_disp.s,v 1.7 2008/01/13 20:59:52 kettenis Exp $ */
2/* $NetBSD: prom_disp.s,v 1.8 1997/11/03 04:22:03 ross Exp $ */
3
4/*
5 * Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University.
6 * All rights reserved.
7 *
8 * Author: Chris G. Demetriou
9 *
10 * Permission to use, copy, modify and distribute this software and
11 * its documentation is hereby granted, provided that both the copyright
12 * notice and this permission notice appear in all copies of the
13 * software, derivative works or modified versions, and any portions
14 * thereof, and that both notices appear in supporting documentation.
15 *
16 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
17 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
18 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
19 *
20 * Carnegie Mellon requests users of this software to return to
21 *
22 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
23 *  School of Computer Science
24 *  Carnegie Mellon University
25 *  Pittsburgh PA 15213-3890
26 *
27 * any improvements or extensions that they make and grant Carnegie the
28 * rights to redistribute these changes.
29 */
30
31.file	2 __FILE__
32.loc	2 __LINE__
33
34#ifndef _LOCORE
35#include <machine/asm.h>
36#endif
37
38	.globl	prom_dispatch_v
39	.comm	prom_dispatch_v,16
40
41	.text
42	.align	4
43
44/*
45 * Dispatcher routine.  Implements prom's calling machinery, saves our
46 * callee-saved registers as required by C.
47 */
48#define	D_RA			 (7*8)
49#define	D_S0			 (8*8)
50#define	D_S1			 (9*8)
51#define	D_S2			(10*8)
52#define	D_S3			(11*8)
53#define	D_S4			(12*8)
54#define	D_S5			(13*8)
55#define	D_S6			(14*8)
56#define	DISPATCH_FRAME_SIZE	(15*8)
57#define	DISPATCH_REGS		IM_RA|IM_S0|IM_S1|IM_S2|IM_S3|IM_S4|IM_S5|IM_S6
58
59NESTED(prom_dispatch, 5, DISPATCH_FRAME_SIZE, ra, DISPATCH_REGS, 0)
60
61	ldgp	gp, 0(pv)
62
63	lda	sp, -DISPATCH_FRAME_SIZE(sp)
64	stq	ra, D_RA(sp)
65	stq	s0, D_S0(sp)
66	stq	s1, D_S1(sp)
67	stq	s2, D_S2(sp)
68	stq	s3, D_S3(sp)
69	stq	s4, D_S4(sp)
70	stq	s5, D_S5(sp)
71	stq	s6, D_S6(sp)
72
73	/* Lord have mercy because.. I would not. */
74#define	STUPID_PROM_IS_32_BITS
75#ifdef	STUPID_PROM_IS_32_BITS
76	ldah	s0, 0x2000(zero)	/* hack for hack */
77	lda	s0, (0x2000-8)(s0)
78
79	stq	sp, 0(s0)
80	or	s0, zero, sp
81#endif	/* STUPID_PROM_IS_32_BITS */
82
83	lda	pv, prom_dispatch_v
84	ldq	v0, 0(pv)		/* routine */
85	ldq	pv, 8(pv)		/* routine_arg */
86
87	jsr	ra, (v0)
88
89#ifdef	STUPID_PROM_IS_32_BITS
90	ldah	s0, 0x2000(zero)	/* hack for hack */
91	lda	s0, (0x2000-8)(s0)
92
93	ldq	sp, 0(s0)
94#endif	/* STUPID_PROM_IS_32_BITS */
95
96	ldq	ra, D_RA(sp)
97	ldq	s0, D_S0(sp)
98	ldq	s1, D_S1(sp)
99	ldq	s2, D_S2(sp)
100	ldq	s3, D_S3(sp)
101	ldq	s4, D_S4(sp)
102	ldq	s5, D_S5(sp)
103	ldq	s6, D_S6(sp)
104	lda	sp, DISPATCH_FRAME_SIZE(sp)
105	RET
106END(prom_dispatch)
107
108#undef	D_RA
109#undef	D_S0
110#undef	D_S1
111#undef	D_S2
112#undef	D_S3
113#undef	D_S4
114#undef	D_S5
115#undef	D_S6
116#undef	DISPATCH_FRAME_SIZE
117#undef	DISPATCH_REGS
118