1/*        $NetBSD: swapcontext.S,v 1.5 2021/07/06 12:38:40 thorpej Exp $        */
2
3/*-
4 * Copyright (c) 2001 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Klaus Klein.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include "SYS.h"
33#include "assym.h"
34
35#define   FRAME_SIZE          32
36#define   FRAME_RA  (32-16)
37#define   FRAME_OUCP          (32-24)
38#define   FRAME_UCP (32-32)
39
40NESTED(swapcontext, 2, FRAME_SIZE, ra, IM_RA|IM_A0|IM_A1, 0)
41          LDGP(pv)
42          lda       sp, -FRAME_SIZE(sp)
43          stq       ra, FRAME_RA(sp)    /* must save ra, oucp, ucp */
44          stq       a0, FRAME_OUCP(sp)
45          stq       a1, FRAME_UCP(sp)
46          CALL(_getcontext)             /* getcontext(oucp) */
47          ldq       t0, FRAME_OUCP(sp)
48          bne       v0, Lerr
49          ldq       t1, FRAME_RA(sp)
50          stq       t1, (UC_GREGS + _REG_RA*8)(t0)          /* Adjust saved RA */
51          stq       t1, (UC_GREGS + _REG_PC*8)(t0)          /* Adjust saved PC */
52          lda       t1, FRAME_SIZE(sp)
53          stq       t1, (UC_GREGS + _REG_SP*8)(t0)          /* Adjust saved SP */
54
55          ldq       a0, FRAME_UCP(sp)
56          CALL(setcontext)              /* setcontext(ucp) */
57Lerr:
58          ldq       ra, FRAME_RA(sp)
59          lda       sp, FRAME_SIZE(sp)
60          RET
61END(swapcontext)
62