xref: /linux/drivers/tty/hvc/hvc_riscv_sbi.c (revision 23c48a124b469cee2eb0c75e6d22d366d1caa118)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2008 David Gibson, IBM Corporation
4  * Copyright (C) 2012 Regents of the University of California
5  * Copyright (C) 2017 SiFive
6  */
7 
8 #include <linux/console.h>
9 #include <linux/err.h>
10 #include <linux/init.h>
11 #include <linux/moduleparam.h>
12 #include <linux/types.h>
13 
14 #include <asm/sbi.h>
15 
16 #include "hvc_console.h"
17 
18 static int hvc_sbi_tty_put(uint32_t vtermno, const char *buf, int count)
19 {
20 	int i;
21 
22 	for (i = 0; i < count; i++)
23 		sbi_console_putchar(buf[i]);
24 
25 	return i;
26 }
27 
28 static int hvc_sbi_tty_get(uint32_t vtermno, char *buf, int count)
29 {
30 	int i, c;
31 
32 	for (i = 0; i < count; i++) {
33 		c = sbi_console_getchar();
34 		if (c < 0)
35 			break;
36 		buf[i] = c;
37 	}
38 
39 	return i;
40 }
41 
42 static const struct hv_ops hvc_sbi_ops = {
43 	.get_chars = hvc_sbi_tty_get,
44 	.put_chars = hvc_sbi_tty_put,
45 };
46 
47 static int __init hvc_sbi_init(void)
48 {
49 	return PTR_ERR_OR_ZERO(hvc_alloc(0, 0, &hvc_sbi_ops, 16));
50 }
51 device_initcall(hvc_sbi_init);
52 
53 static int __init hvc_sbi_console_init(void)
54 {
55 	hvc_instantiate(0, 0, &hvc_sbi_ops);
56 
57 	return 0;
58 }
59 console_initcall(hvc_sbi_console_init);
60