1 /*
2 * Beat hypervisor console driver
3 *
4 * (C) Copyright 2006 TOSHIBA CORPORATION
5 *
6 * This code is based on drivers/char/hvc_rtas.c:
7 * (C) Copyright IBM Corporation 2001-2005
8 * (C) Copyright Red Hat, Inc. 2005
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License along
21 * with this program; if not, write to the Free Software Foundation, Inc.,
22 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
23 */
24
25 #include <linux/module.h>
26 #include <linux/init.h>
27 #include <linux/err.h>
28 #include <linux/string.h>
29 #include <linux/console.h>
30 #include <asm/prom.h>
31 #include <asm/hvconsole.h>
32 #include <asm/firmware.h>
33
34 #include "hvc_console.h"
35
36 extern int64_t beat_get_term_char(uint64_t, uint64_t *, uint64_t *, uint64_t *);
37 extern int64_t beat_put_term_char(uint64_t, uint64_t, uint64_t, uint64_t);
38
39 struct hvc_struct *hvc_beat_dev = NULL;
40
41 /* bug: only one queue is available regardless of vtermno */
hvc_beat_get_chars(uint32_t vtermno,char * buf,int cnt)42 static int hvc_beat_get_chars(uint32_t vtermno, char *buf, int cnt)
43 {
44 static unsigned char q[sizeof(unsigned long) * 2]
45 __attribute__((aligned(sizeof(unsigned long))));
46 static int qlen = 0;
47 u64 got;
48
49 again:
50 if (qlen) {
51 if (qlen > cnt) {
52 memcpy(buf, q, cnt);
53 qlen -= cnt;
54 memmove(q + cnt, q, qlen);
55 return cnt;
56 } else { /* qlen <= cnt */
57 int r;
58
59 memcpy(buf, q, qlen);
60 r = qlen;
61 qlen = 0;
62 return r;
63 }
64 }
65 if (beat_get_term_char(vtermno, &got,
66 ((u64 *)q), ((u64 *)q) + 1) == 0) {
67 qlen = got;
68 goto again;
69 }
70 return 0;
71 }
72
hvc_beat_put_chars(uint32_t vtermno,const char * buf,int cnt)73 static int hvc_beat_put_chars(uint32_t vtermno, const char *buf, int cnt)
74 {
75 unsigned long kb[2];
76 int rest, nlen;
77
78 for (rest = cnt; rest > 0; rest -= nlen) {
79 nlen = (rest > 16) ? 16 : rest;
80 memcpy(kb, buf, nlen);
81 beat_put_term_char(vtermno, nlen, kb[0], kb[1]);
82 buf += nlen;
83 }
84 return cnt;
85 }
86
87 static const struct hv_ops hvc_beat_get_put_ops = {
88 .get_chars = hvc_beat_get_chars,
89 .put_chars = hvc_beat_put_chars,
90 };
91
92 static int hvc_beat_useit = 1;
93
hvc_beat_config(char * p)94 static int hvc_beat_config(char *p)
95 {
96 hvc_beat_useit = simple_strtoul(p, NULL, 0);
97 return 0;
98 }
99
hvc_beat_console_init(void)100 static int __init hvc_beat_console_init(void)
101 {
102 if (hvc_beat_useit && of_machine_is_compatible("Beat")) {
103 hvc_instantiate(0, 0, &hvc_beat_get_put_ops);
104 }
105 return 0;
106 }
107
108 /* temp */
hvc_beat_init(void)109 static int __init hvc_beat_init(void)
110 {
111 struct hvc_struct *hp;
112
113 if (!firmware_has_feature(FW_FEATURE_BEAT))
114 return -ENODEV;
115
116 hp = hvc_alloc(0, 0, &hvc_beat_get_put_ops, 16);
117 if (IS_ERR(hp))
118 return PTR_ERR(hp);
119 hvc_beat_dev = hp;
120 return 0;
121 }
122
hvc_beat_exit(void)123 static void __exit hvc_beat_exit(void)
124 {
125 if (hvc_beat_dev)
126 hvc_remove(hvc_beat_dev);
127 }
128
129 module_init(hvc_beat_init);
130 module_exit(hvc_beat_exit);
131
132 __setup("hvc_beat=", hvc_beat_config);
133
134 console_initcall(hvc_beat_console_init);
135