aboutsummaryrefslogtreecommitdiff
path: root/drivers/char/hvc_beat.c
blob: 5fe4631e2a6135f1fb2c417246b7e306e980475b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
/*
 * Beat hypervisor console driver
 *
 * (C) Copyright 2006 TOSHIBA CORPORATION
 *
 * This code is based on drivers/char/hvc_rtas.c:
 * (C) Copyright IBM Corporation 2001-2005
 * (C) Copyright Red Hat, Inc. 2005
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/string.h>
#include <linux/console.h>
#include <asm/prom.h>
#include <asm/hvconsole.h>
#include <asm/firmware.h>

#include "hvc_console.h"

extern int64_t beat_get_term_char(uint64_t, uint64_t *, uint64_t *, uint64_t *);
extern int64_t beat_put_term_char(uint64_t, uint64_t, uint64_t, uint64_t);

struct hvc_struct *hvc_beat_dev = NULL;

/* bug: only one queue is available regardless of vtermno */
static int hvc_beat_get_chars(uint32_t vtermno, char *buf, int cnt)
{
	static unsigned char q[sizeof(unsigned long) * 2]
		__attribute__((aligned(sizeof(unsigned long))));
	static int qlen = 0;
	u64 got;

again:
	if (qlen) {
		if (qlen > cnt) {
			memcpy(buf, q, cnt);
			qlen -= cnt;
			memmove(q + cnt, q, qlen);
			return cnt;
		} else {	/* qlen <= cnt */
			int	r;

			memcpy(buf, q, qlen);
			r = qlen;
			qlen = 0;
			return r;
		}
	}
	if (beat_get_term_char(vtermno, &got,
		((u64 *)q), ((u64 *)q) + 1) == 0) {
		qlen = got;
		goto again;
	}
	return 0;
}

static int hvc_beat_put_chars(uint32_t vtermno, const char *buf, int cnt)
{
	unsigned long kb[2];
	int rest, nlen;

	for (rest = cnt; rest > 0; rest -= nlen) {
		nlen = (rest > 16) ? 16 : rest;
		memcpy(kb, buf, nlen);
		beat_put_term_char(vtermno, nlen, kb[0], kb[1]);
		buf += nlen;
	}
	return cnt;
}

static const struct hv_ops hvc_beat_get_put_ops = {
	.get_chars = hvc_beat_get_chars,
	.put_chars = hvc_beat_put_chars,
};

static int hvc_beat_useit = 1;

static int hvc_beat_config(char *p)
{
	hvc_beat_useit = simple_strtoul(p, NULL, 0);
	return 0;
}

static int __init hvc_beat_console_init(void)
{
	if (hvc_beat_useit && of_machine_is_compatible("Beat")) {
		hvc_instantiate(0, 0, &hvc_beat_get_put_ops);
	}
	return 0;
}

/* temp */
static int __init hvc_beat_init(void)
{
	struct hvc_struct *hp;

	if (!firmware_has_feature(FW_FEATURE_BEAT))
		return -ENODEV;

	hp = hvc_alloc(0, NO_IRQ, &hvc_beat_get_put_ops, 16);
	if (IS_ERR(hp))
		return PTR_ERR(hp);
	hvc_beat_dev = hp;
	return 0;
}

static void __exit hvc_beat_exit(void)
{
	if (hvc_beat_dev)
		hvc_remove(hvc_beat_dev);
}

module_init(hvc_beat_init);
module_exit(hvc_beat_exit);

__setup("hvc_beat=", hvc_beat_config);

console_initcall(hvc_beat_console_init);