aboutsummaryrefslogtreecommitdiffstats
path: root/arch/powerpc/sysdev/mv64x60_udbg.c
blob: 35c77c7d06168482ec27db5405228468a9c3a0ab (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
/*
 * udbg serial input/output routines for the Marvell MV64x60 (Discovery).
 *
 * Author: Dale Farnsworth <dale@farnsworth.org>
 *
 * 2007 (c) MontaVista Software, Inc.  This file is licensed under
 * the terms of the GNU General Public License version 2.  This program
 * is licensed "as is" without any warranty of any kind, whether express
 * or implied.
 */

#include <asm/io.h>
#include <asm/prom.h>
#include <asm/udbg.h>

#include <sysdev/mv64x60.h>

#define MPSC_0_CR1_OFFSET	0x000c

#define MPSC_0_CR2_OFFSET	0x0010
#define MPSC_CHR_2_TCS		(1 << 9)

#define MPSC_0_CHR_10_OFFSET	0x0030

#define MPSC_INTR_CAUSE_OFF_0	0x0004
#define MPSC_INTR_CAUSE_OFF_1	0x000c
#define MPSC_INTR_CAUSE_RCC	(1<<6)

static void __iomem *mpsc_base;
static void __iomem *mpsc_intr_cause;

static void mv64x60_udbg_putc(char c)
{
	if (c == '\n')
		mv64x60_udbg_putc('\r');

	while(in_le32(mpsc_base + MPSC_0_CR2_OFFSET) & MPSC_CHR_2_TCS)
		;
	out_le32(mpsc_base + MPSC_0_CR1_OFFSET, c);
	out_le32(mpsc_base + MPSC_0_CR2_OFFSET, MPSC_CHR_2_TCS);
}

static int mv64x60_udbg_testc(void)
{
	return (in_le32(mpsc_intr_cause) & MPSC_INTR_CAUSE_RCC) != 0;
}

static int mv64x60_udbg_getc(void)
{
	int cause = 0;
	int c;

	while (!mv64x60_udbg_testc())
		;

	c = in_8(mpsc_base + MPSC_0_CHR_10_OFFSET + 2);
	out_8(mpsc_base + MPSC_0_CHR_10_OFFSET + 2, c);
	out_le32(mpsc_intr_cause, cause & ~MPSC_INTR_CAUSE_RCC);
	return c;
}

static int mv64x60_udbg_getc_poll(void)
{
	if (!mv64x60_udbg_testc())
		return -1;

	return mv64x60_udbg_getc();
}

static void mv64x60_udbg_init(void)
{
	struct device_node *np, *mpscintr, *stdout = NULL;
	const char *path;
	const phandle *ph;
	struct resource r[2];
	const int *block_index;
	int intr_cause_offset;
	int err;

	path = of_get_property(of_chosen, "linux,stdout-path", NULL);
	if (!path)
		return;

	stdout = of_find_node_by_path(path);
	if (!stdout)
		return;

	for_each_compatible_node(np, "serial", "marvell,mpsc") {
		if (np == stdout)
			break;
	}

	of_node_put(stdout);
	if (!np)
		return;

	block_index = of_get_property(np, "block-index", NULL);
	if (!block_index)
		goto error;

	switch (*block_index) {
	case 0:
		intr_cause_offset = MPSC_INTR_CAUSE_OFF_0;
		break;
	case 1:
		intr_cause_offset = MPSC_INTR_CAUSE_OFF_1;
		break;
	default:
		goto error;
	}

	err = of_address_to_resource(np, 0, &r[0]);
	if (err)
		goto error;

	ph = of_get_property(np, "mpscintr", NULL);
	mpscintr = of_find_node_by_phandle(*ph);
	if (!mpscintr)
		goto error;

	err = of_address_to_resource(mpscintr, 0, &r[1]);
	of_node_put(mpscintr);
	if (err)
		goto error;

	of_node_put(np);

	mpsc_base = ioremap(r[0].start, r[0].end - r[0].start + 1);
	if (!mpsc_base)
		return;

	mpsc_intr_cause = ioremap(r[1].start, r[1].end - r[1].start + 1);
	if (!mpsc_intr_cause) {
		iounmap(mpsc_base);
		return;
	}
	mpsc_intr_cause += intr_cause_offset;

	udbg_putc = mv64x60_udbg_putc;
	udbg_getc = mv64x60_udbg_getc;
	udbg_getc_poll = mv64x60_udbg_getc_poll;

	return;

error:
	of_node_put(np);
}

void mv64x60_init_early(void)
{
	mv64x60_udbg_init();
}