1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* |
3 | * udbg interface to hvc_console.c |
4 | * |
5 | * (C) Copyright David Gibson, IBM Corporation 2008. |
6 | */ |
7 | |
8 | #include <linux/console.h> |
9 | #include <linux/delay.h> |
10 | #include <linux/err.h> |
11 | #include <linux/init.h> |
12 | #include <linux/moduleparam.h> |
13 | #include <linux/types.h> |
14 | #include <linux/irq.h> |
15 | |
16 | #include <asm/udbg.h> |
17 | |
18 | #include "hvc_console.h" |
19 | |
20 | static struct hvc_struct *hvc_udbg_dev; |
21 | |
22 | static ssize_t hvc_udbg_put(uint32_t vtermno, const u8 *buf, size_t count) |
23 | { |
24 | size_t i; |
25 | |
26 | for (i = 0; i < count && udbg_putc; i++) |
27 | udbg_putc(buf[i]); |
28 | |
29 | return i; |
30 | } |
31 | |
32 | static ssize_t hvc_udbg_get(uint32_t vtermno, u8 *buf, size_t count) |
33 | { |
34 | size_t i; |
35 | int c; |
36 | |
37 | if (!udbg_getc_poll) |
38 | return 0; |
39 | |
40 | for (i = 0; i < count; i++) { |
41 | if ((c = udbg_getc_poll()) == -1) |
42 | break; |
43 | buf[i] = c; |
44 | } |
45 | |
46 | return i; |
47 | } |
48 | |
49 | static const struct hv_ops hvc_udbg_ops = { |
50 | .get_chars = hvc_udbg_get, |
51 | .put_chars = hvc_udbg_put, |
52 | }; |
53 | |
54 | static int __init hvc_udbg_init(void) |
55 | { |
56 | struct hvc_struct *hp; |
57 | |
58 | if (!udbg_putc) |
59 | return -ENODEV; |
60 | |
61 | BUG_ON(hvc_udbg_dev); |
62 | |
63 | hp = hvc_alloc(vtermno: 0, data: 0, ops: &hvc_udbg_ops, outbuf_size: 16); |
64 | if (IS_ERR(ptr: hp)) |
65 | return PTR_ERR(ptr: hp); |
66 | |
67 | hvc_udbg_dev = hp; |
68 | |
69 | return 0; |
70 | } |
71 | device_initcall(hvc_udbg_init); |
72 | |
73 | static int __init hvc_udbg_console_init(void) |
74 | { |
75 | if (!udbg_putc) |
76 | return -ENODEV; |
77 | |
78 | hvc_instantiate(vtermno: 0, index: 0, ops: &hvc_udbg_ops); |
79 | add_preferred_console(name: "hvc" , idx: 0, NULL); |
80 | |
81 | return 0; |
82 | } |
83 | console_initcall(hvc_udbg_console_init); |
84 | |