iris_start.S revision 1.1 1 /* $NetBSD: iris_start.S,v 1.1 2019/01/12 16:44:47 tsutsui Exp $ */
2
3 /*
4 * Copyright (c) 2018 Naruaki Etomi
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 /*
29 * Silicon Graphics "IRIS" series MIPS processors machine bootloader.
30 */
31
32 #include <mips/asm.h>
33 #include <mips/cpuregs.h>
34
35 .globl start
36 start:
37 .set noreorder
38 #ifdef __GP_SUPPORT__
39 la gp, _C_LABEL(_gp)
40 #endif
41 /*
42 * We assume the bootprom isn't expecting us to preserve the saved
43 * registers.
44 */
45 move s0, a0 # save argc
46 move s1, a1 # save argv
47 move s2, a2 # save envp
48 move s3, ra # save RA
49
50 la a0, _C_LABEL(edata) # clear BSS
51 move a1, zero
52 la a2, _C_LABEL(end)
53 jal _C_LABEL(memset) # memset(edata, 0, end - edata)
54 subu a2, a2, a0
55
56 move a0, s0 # restore argc
57 move a1, s1 # restore argv
58 move a2, s2 # restore envp
59 j _C_LABEL(main) # main(argc, argv)
60 move ra, s3 # restore RA
61
62 LEAF(romrestart)
63 XLEAF(_rtt)
64 PTR_LA v0, 0xBFC00000 # indigo RESET
65 j v0
66 nop
67 END(romrestart)
68