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
|
/*
* udbg for for zilog scc ports as found on Apple PowerMacs
*
* Copyright (C) 2001-2005 PPC 64 Team, IBM Corp
*
* 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.
*/
#include <linux/types.h>
#include <asm/udbg.h>
#include <asm/processor.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pmac_feature.h>
extern u8 real_readb(volatile u8 __iomem *addr);
extern void real_writeb(u8 data, volatile u8 __iomem *addr);
#define SCC_TXRDY 4
#define SCC_RXRDY 1
static volatile u8 __iomem *sccc;
static volatile u8 __iomem *sccd;
static void udbg_scc_putc(char c)
{
if (sccc) {
while ((in_8(sccc) & SCC_TXRDY) == 0)
;
out_8(sccd, c);
if (c == '\n')
udbg_scc_putc('\r');
}
}
static int udbg_scc_getc_poll(void)
{
if (sccc) {
if ((in_8(sccc) & SCC_RXRDY) != 0)
return in_8(sccd);
else
return -1;
}
return -1;
}
static int udbg_scc_getc(void)
{
if (sccc) {
while ((in_8(sccc) & SCC_RXRDY) == 0)
;
return in_8(sccd);
}
return -1;
}
static unsigned char scc_inittab[] = {
13, 0, /* set baud rate divisor */
12, 0,
14, 1, /* baud rate gen enable, src=rtxc */
11, 0x50, /* clocks = br gen */
5, 0xea, /* tx 8 bits, assert DTR & RTS */
4, 0x46, /* x16 clock, 1 stop */
3, 0xc1, /* rx enable, 8 bits */
};
void udbg_scc_init(int force_scc)
{
const u32 *reg;
unsigned long addr;
struct device_node *stdout = NULL, *escc = NULL, *macio = NULL;
struct device_node *ch, *ch_def = NULL, *ch_a = NULL;
const char *path;
int i, x;
escc = of_find_node_by_name(NULL, "escc");
if (escc == NULL)
goto bail;
macio = of_get_parent(escc);
if (macio == NULL)
goto bail;
path = get_property(of_chosen, "linux,stdout-path", NULL);
if (path != NULL)
stdout = of_find_node_by_path(path);
for (ch = NULL; (ch = of_get_next_child(escc, ch)) != NULL;) {
if (ch == stdout)
ch_def = of_node_get(ch);
if (strcmp(ch->name, "ch-a") == 0)
ch_a = of_node_get(ch);
}
if (ch_def == NULL && !force_scc)
goto bail;
ch = ch_def ? ch_def : ch_a;
/* Get address within mac-io ASIC */
reg = get_property(escc, "reg", NULL);
if (reg == NULL)
goto bail;
addr = reg[0];
/* Get address of mac-io PCI itself */
reg = get_property(macio, "assigned-addresses", NULL);
if (reg == NULL)
goto bail;
addr += reg[2];
/* Lock the serial port */
pmac_call_feature(PMAC_FTR_SCC_ENABLE, ch,
PMAC_SCC_ASYNC | PMAC_SCC_FLAG_XMON, 1);
if (ch == ch_a)
addr += 0x20;
sccc = ioremap(addr & PAGE_MASK, PAGE_SIZE) ;
sccc += addr & ~PAGE_MASK;
sccd = sccc + 0x10;
mb();
for (i = 20000; i != 0; --i)
x = in_8(sccc);
out_8(sccc, 0x09); /* reset A or B side */
out_8(sccc, 0xc0);
/* If SCC was the OF output port, read the BRG value, else
* Setup for 57600 8N1
*/
if (ch_def != NULL) {
out_8(sccc, 13);
scc_inittab[1] = in_8(sccc);
out_8(sccc, 12);
scc_inittab[3] = in_8(sccc);
}
for (i = 0; i < sizeof(scc_inittab); ++i)
out_8(sccc, scc_inittab[i]);
udbg_putc = udbg_scc_putc;
udbg_getc = udbg_scc_getc;
udbg_getc_poll = udbg_scc_getc_poll;
udbg_puts("Hello World !\n");
bail:
of_node_put(macio);
of_node_put(escc);
of_node_put(stdout);
of_node_put(ch_def);
of_node_put(ch_a);
}
#ifdef CONFIG_PPC64
static void udbg_real_scc_putc(char c)
{
while ((real_readb(sccc) & SCC_TXRDY) == 0)
;
real_writeb(c, sccd);
if (c == '\n')
udbg_real_scc_putc('\r');
}
void __init udbg_init_pmac_realmode(void)
{
sccc = (volatile u8 __iomem *)0x80013020ul;
sccd = (volatile u8 __iomem *)0x80013030ul;
udbg_putc = udbg_real_scc_putc;
udbg_getc = NULL;
udbg_getc_poll = NULL;
}
#endif /* CONFIG_PPC64 */
|
