1e3b3d0f5SGreg Kroah-Hartman // SPDX-License-Identifier: GPL-2.0+
2728674a7SGreg Kroah-Hartman /*
3728674a7SGreg Kroah-Hartman * IBM RTAS driver interface to hvc_console.c
4728674a7SGreg Kroah-Hartman *
5728674a7SGreg Kroah-Hartman * (C) Copyright IBM Corporation 2001-2005
6728674a7SGreg Kroah-Hartman * (C) Copyright Red Hat, Inc. 2005
7728674a7SGreg Kroah-Hartman *
8728674a7SGreg Kroah-Hartman * Author(s): Maximino Augilar <IBM STI Design Center>
9728674a7SGreg Kroah-Hartman * : Ryan S. Arnold <rsa@us.ibm.com>
10728674a7SGreg Kroah-Hartman * : Utz Bacher <utz.bacher@de.ibm.com>
11728674a7SGreg Kroah-Hartman * : David Woodhouse <dwmw2@infradead.org>
12728674a7SGreg Kroah-Hartman *
13728674a7SGreg Kroah-Hartman * inspired by drivers/char/hvc_console.c
14728674a7SGreg Kroah-Hartman * written by Anton Blanchard and Paul Mackerras
15728674a7SGreg Kroah-Hartman */
16728674a7SGreg Kroah-Hartman
17728674a7SGreg Kroah-Hartman #include <linux/console.h>
18728674a7SGreg Kroah-Hartman #include <linux/delay.h>
19728674a7SGreg Kroah-Hartman #include <linux/err.h>
20728674a7SGreg Kroah-Hartman #include <linux/init.h>
21728674a7SGreg Kroah-Hartman #include <linux/moduleparam.h>
22728674a7SGreg Kroah-Hartman #include <linux/types.h>
23728674a7SGreg Kroah-Hartman
24728674a7SGreg Kroah-Hartman #include <asm/irq.h>
25728674a7SGreg Kroah-Hartman #include <asm/rtas.h>
26728674a7SGreg Kroah-Hartman #include "hvc_console.h"
27728674a7SGreg Kroah-Hartman
28728674a7SGreg Kroah-Hartman #define hvc_rtas_cookie 0x67781e15
29*cc72a1eeSruanjinjie static struct hvc_struct *hvc_rtas_dev;
30728674a7SGreg Kroah-Hartman
31728674a7SGreg Kroah-Hartman static int rtascons_put_char_token = RTAS_UNKNOWN_SERVICE;
32728674a7SGreg Kroah-Hartman static int rtascons_get_char_token = RTAS_UNKNOWN_SERVICE;
33728674a7SGreg Kroah-Hartman
hvc_rtas_write_console(uint32_t vtermno,const char * buf,int count)34728674a7SGreg Kroah-Hartman static inline int hvc_rtas_write_console(uint32_t vtermno, const char *buf,
35728674a7SGreg Kroah-Hartman int count)
36728674a7SGreg Kroah-Hartman {
37728674a7SGreg Kroah-Hartman int i;
38728674a7SGreg Kroah-Hartman
39728674a7SGreg Kroah-Hartman for (i = 0; i < count; i++) {
40728674a7SGreg Kroah-Hartman if (rtas_call(rtascons_put_char_token, 1, 1, NULL, buf[i]))
41728674a7SGreg Kroah-Hartman break;
42728674a7SGreg Kroah-Hartman }
43728674a7SGreg Kroah-Hartman
44728674a7SGreg Kroah-Hartman return i;
45728674a7SGreg Kroah-Hartman }
46728674a7SGreg Kroah-Hartman
hvc_rtas_read_console(uint32_t vtermno,char * buf,int count)47728674a7SGreg Kroah-Hartman static int hvc_rtas_read_console(uint32_t vtermno, char *buf, int count)
48728674a7SGreg Kroah-Hartman {
49728674a7SGreg Kroah-Hartman int i, c;
50728674a7SGreg Kroah-Hartman
51728674a7SGreg Kroah-Hartman for (i = 0; i < count; i++) {
52728674a7SGreg Kroah-Hartman if (rtas_call(rtascons_get_char_token, 0, 2, &c))
53728674a7SGreg Kroah-Hartman break;
54728674a7SGreg Kroah-Hartman
55728674a7SGreg Kroah-Hartman buf[i] = c;
56728674a7SGreg Kroah-Hartman }
57728674a7SGreg Kroah-Hartman
58728674a7SGreg Kroah-Hartman return i;
59728674a7SGreg Kroah-Hartman }
60728674a7SGreg Kroah-Hartman
61728674a7SGreg Kroah-Hartman static const struct hv_ops hvc_rtas_get_put_ops = {
62728674a7SGreg Kroah-Hartman .get_chars = hvc_rtas_read_console,
63728674a7SGreg Kroah-Hartman .put_chars = hvc_rtas_write_console,
64728674a7SGreg Kroah-Hartman };
65728674a7SGreg Kroah-Hartman
hvc_rtas_init(void)66728674a7SGreg Kroah-Hartman static int __init hvc_rtas_init(void)
67728674a7SGreg Kroah-Hartman {
68728674a7SGreg Kroah-Hartman struct hvc_struct *hp;
69728674a7SGreg Kroah-Hartman
70728674a7SGreg Kroah-Hartman if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
71728674a7SGreg Kroah-Hartman rtascons_put_char_token = rtas_token("put-term-char");
72728674a7SGreg Kroah-Hartman if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
73728674a7SGreg Kroah-Hartman return -EIO;
74728674a7SGreg Kroah-Hartman
75728674a7SGreg Kroah-Hartman if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
76728674a7SGreg Kroah-Hartman rtascons_get_char_token = rtas_token("get-term-char");
77728674a7SGreg Kroah-Hartman if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
78728674a7SGreg Kroah-Hartman return -EIO;
79728674a7SGreg Kroah-Hartman
80728674a7SGreg Kroah-Hartman BUG_ON(hvc_rtas_dev);
81728674a7SGreg Kroah-Hartman
82728674a7SGreg Kroah-Hartman /* Allocate an hvc_struct for the console device we instantiated
83728674a7SGreg Kroah-Hartman * earlier. Save off hp so that we can return it on exit */
84d4e33facSAlan Cox hp = hvc_alloc(hvc_rtas_cookie, 0, &hvc_rtas_get_put_ops, 16);
85728674a7SGreg Kroah-Hartman if (IS_ERR(hp))
86728674a7SGreg Kroah-Hartman return PTR_ERR(hp);
87728674a7SGreg Kroah-Hartman
88728674a7SGreg Kroah-Hartman hvc_rtas_dev = hp;
89728674a7SGreg Kroah-Hartman
90728674a7SGreg Kroah-Hartman return 0;
91728674a7SGreg Kroah-Hartman }
924fedd0bfSPaul Gortmaker device_initcall(hvc_rtas_init);
93728674a7SGreg Kroah-Hartman
94728674a7SGreg Kroah-Hartman /* This will happen prior to module init. There is no tty at this time? */
hvc_rtas_console_init(void)95728674a7SGreg Kroah-Hartman static int __init hvc_rtas_console_init(void)
96728674a7SGreg Kroah-Hartman {
97728674a7SGreg Kroah-Hartman rtascons_put_char_token = rtas_token("put-term-char");
98728674a7SGreg Kroah-Hartman if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
99728674a7SGreg Kroah-Hartman return -EIO;
100728674a7SGreg Kroah-Hartman
101728674a7SGreg Kroah-Hartman rtascons_get_char_token = rtas_token("get-term-char");
102728674a7SGreg Kroah-Hartman if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
103728674a7SGreg Kroah-Hartman return -EIO;
104728674a7SGreg Kroah-Hartman
105728674a7SGreg Kroah-Hartman hvc_instantiate(hvc_rtas_cookie, 0, &hvc_rtas_get_put_ops);
106728674a7SGreg Kroah-Hartman add_preferred_console("hvc", 0, NULL);
107728674a7SGreg Kroah-Hartman
108728674a7SGreg Kroah-Hartman return 0;
109728674a7SGreg Kroah-Hartman }
110728674a7SGreg Kroah-Hartman console_initcall(hvc_rtas_console_init);
111