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1 /*
2 * Semihosting Console Test
3 *
4 * Copyright (c) 2019 Linaro Ltd
5 *
6 * SPDX-License-Identifier: GPL-2.0-or-later
7 */
8
9 #include <stdint.h>
10 #include <minilib.h>
11
12 #define SYS_READC 0x7
13
14 uintptr_t __semi_call(uintptr_t type, uintptr_t arg0)
15 {
16 register uintptr_t t asm("r0") = type;
17 register uintptr_t a0 asm("r1") = arg0;
18 #ifdef __thumb__
19 # define SVC "svc 0xab"
20 #else
21 # define SVC "svc 0x123456"
22 #endif
23 asm(SVC : "=r" (t)
24 : "r" (t), "r" (a0));
25
26 return t;
27 }
28
29 int main(void)
30 {
31 char c;
32
33 ml_printf("Semihosting Console Test\n");
34 ml_printf("hit X to exit:");
35
36 do {
37 c = __semi_call(SYS_READC, 0);
38 __sys_outc(c);
39 } while (c != 'X');
40
41 return 0;
42 }