1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
|
/* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* crt0.S -- PRU startup code
*
* Copyright (c) 2018-2019 Dimitar Dimitrov <dimitar@dinux.eu>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "newlib.h"
.extern main
.extern exit
.text
.section .init0, "x"
.global _start
_start:
/* Initialize stack pointer. */
ldi32 sp, _stack_top
/* DATA and BSS are handled by the loader, so nothing to do here. */
.extern _do_global_dtors
/* Ensure destructors get called. Call is per GNU ABI (i.e. 32-bit
function pointers). But it is also compatible with the TI ABI
since GCC supports only little endian PRU.
WARNING: Keep this compatible with both ABIs! */
ldi r14, %pmem(_do_global_dtors)
call atexit
/* Call constructors. Use non-call-clobbered registers. */
ldi r5, __init_array_start
ldi r6, __init_array_end
ctors_loop:
qbeq ctors_done, r5, r6
/* ABI dictates 16-bit IMEM pointers. */
lbbo r7, r5, 0, 2
call r7.w0
add r5, r5, 2
jmp ctors_loop
ctors_done:
/* Just in case main() tries to access argc, argv[] and envp. */
zero r14, 3 * 4
.weak __c_args__
ldi32 r5, __c_args__
qbeq __skip_c_args, r5, 0
lbbo r14, r5, 0, 4 /* argc */
add r15, r5, 4 /* argv */
__skip_c_args:
/* Call main */
call main
/* Call exit */
call exit
/* We should never reach here. */
_crt_exit:
halt
jmp _crt_exit
/* PRU obviously has no shared libraries, but dso_handle
helps to achieve better GCC test coverage. Besides,
it should be free with minrt. */
.section .data
.global __dso_handle
.weak __dso_handle
__dso_handle:
.long 0
|
