summaryrefslogtreecommitdiffstats
path: root/drivers/tty/hvc/hvc_tile.c
blob: af8cdaa1dcb90b50d9ee1143e933d51d7fc6696d (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
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
/*
 * Copyright 2010 Tilera Corporation. All Rights Reserved.
 *
 *   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, version 2.
 *
 *   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, GOOD TITLE or
 *   NON INFRINGEMENT.  See the GNU General Public License for
 *   more details.
 *
 * Tilera TILE Processor hypervisor console
 */

#include <linux/console.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/moduleparam.h>
#include <linux/platform_device.h>
#include <linux/types.h>

#include <asm/setup.h>
#include <arch/sim_def.h>

#include <hv/hypervisor.h>

#include "hvc_console.h"

static int use_sim_console;
static int __init sim_console(char *str)
{
	use_sim_console = 1;
	return 0;
}
early_param("sim_console", sim_console);

int tile_console_write(const char *buf, int count)
{
	if (unlikely(use_sim_console)) {
		int i;
		for (i = 0; i < count; ++i)
			__insn_mtspr(SPR_SIM_CONTROL, SIM_CONTROL_PUTC |
				     (buf[i] << _SIM_CONTROL_OPERATOR_BITS));
		__insn_mtspr(SPR_SIM_CONTROL, SIM_CONTROL_PUTC |
			     (SIM_PUTC_FLUSH_BINARY <<
			      _SIM_CONTROL_OPERATOR_BITS));
		return 0;
	} else {
		return hv_console_write((HV_VirtAddr)buf, count);
	}
}

static int hvc_tile_put_chars(uint32_t vt, const char *buf, int count)
{
	return tile_console_write(buf, count);
}

static int hvc_tile_get_chars(uint32_t vt, char *buf, int count)
{
	int i, c;

	for (i = 0; i < count; ++i) {
		c = hv_console_read_if_ready();
		if (c < 0)
			break;
		buf[i] = c;
	}

	return i;
}

#ifdef __tilegx__
/*
 * IRQ based callbacks.
 */
static int hvc_tile_notifier_add_irq(struct hvc_struct *hp, int irq)
{
	int rc;
	int cpu = raw_smp_processor_id();  /* Choose an arbitrary cpu */
	HV_Coord coord = { .x = cpu_x(cpu), .y = cpu_y(cpu) };

	rc = notifier_add_irq(hp, irq);
	if (rc)
		return rc;

	/*
	 * Request that the hypervisor start sending us interrupts.
	 * If the hypervisor returns an error, we still return 0, so that
	 * we can fall back to polling.
	 */
	if (hv_console_set_ipi(KERNEL_PL, irq, coord) < 0)
		notifier_del_irq(hp, irq);

	return 0;
}

static void hvc_tile_notifier_del_irq(struct hvc_struct *hp, int irq)
{
	HV_Coord coord = { 0, 0 };

	/* Tell the hypervisor to stop sending us interrupts. */
	hv_console_set_ipi(KERNEL_PL, -1, coord);

	notifier_del_irq(hp, irq);
}

static void hvc_tile_notifier_hangup_irq(struct hvc_struct *hp, int irq)
{
	hvc_tile_notifier_del_irq(hp, irq);
}
#endif

static const struct hv_ops hvc_tile_get_put_ops = {
	.get_chars = hvc_tile_get_chars,
	.put_chars = hvc_tile_put_chars,
#ifdef __tilegx__
	.notifier_add = hvc_tile_notifier_add_irq,
	.notifier_del = hvc_tile_notifier_del_irq,
	.notifier_hangup = hvc_tile_notifier_hangup_irq,
#endif
};


#ifdef __tilegx__
static int hvc_tile_probe(struct platform_device *pdev)
{
	struct hvc_struct *hp;
	int tile_hvc_irq;

	/* Create our IRQ and register it. */
	tile_hvc_irq = create_irq();
	if (tile_hvc_irq < 0)
		return -ENXIO;

	tile_irq_activate(tile_hvc_irq, TILE_IRQ_PERCPU);
	hp = hvc_alloc(0, tile_hvc_irq, &hvc_tile_get_put_ops, 128);
	if (IS_ERR(hp)) {
		destroy_irq(tile_hvc_irq);
		return PTR_ERR(hp);
	}
	dev_set_drvdata(&pdev->dev, hp);

	return 0;
}

static int hvc_tile_remove(struct platform_device *pdev)
{
	int rc;
	struct hvc_struct *hp = dev_get_drvdata(&pdev->dev);

	rc = hvc_remove(hp);
	if (rc == 0)
		destroy_irq(hp->data);

	return rc;
}

static void hvc_tile_shutdown(struct platform_device *pdev)
{
	struct hvc_struct *hp = dev_get_drvdata(&pdev->dev);

	hvc_tile_notifier_del_irq(hp, hp->data);
}

static struct platform_device hvc_tile_pdev = {
	.name           = "hvc-tile",
	.id             = 0,
};

static struct platform_driver hvc_tile_driver = {
	.probe          = hvc_tile_probe,
	.remove         = hvc_tile_remove,
	.shutdown	= hvc_tile_shutdown,
	.driver         = {
		.name   = "hvc-tile",
		.owner  = THIS_MODULE,
	}
};
#endif

static int __init hvc_tile_console_init(void)
{
	hvc_instantiate(0, 0, &hvc_tile_get_put_ops);
	add_preferred_console("hvc", 0, NULL);
	return 0;
}
console_initcall(hvc_tile_console_init);

static int __init hvc_tile_init(void)
{
#ifndef __tilegx__
	struct hvc_struct *hp;
	hp = hvc_alloc(0, 0, &hvc_tile_get_put_ops, 128);
	return IS_ERR(hp) ? PTR_ERR(hp) : 0;
#else
	platform_device_register(&hvc_tile_pdev);
	return platform_driver_register(&hvc_tile_driver);
#endif
}
device_initcall(hvc_tile_init);
OpenPOWER on IntegriCloud