[POWERPC] maple: Constify & voidify get_property()
[linux-2.6-block.git] / arch / powerpc / platforms / powermac / udbg_scc.c
CommitLineData
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1/*
2 * udbg for for zilog scc ports as found on Apple PowerMacs
3 *
4 * Copyright (C) 2001-2005 PPC 64 Team, IBM Corp
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
7f853352 11#include <linux/types.h>
188d2ce7 12#include <asm/udbg.h>
7f853352 13#include <asm/processor.h>
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14#include <asm/io.h>
15#include <asm/prom.h>
16#include <asm/pmac_feature.h>
17
18extern u8 real_readb(volatile u8 __iomem *addr);
19extern void real_writeb(u8 data, volatile u8 __iomem *addr);
20
21#define SCC_TXRDY 4
22#define SCC_RXRDY 1
23
24static volatile u8 __iomem *sccc;
25static volatile u8 __iomem *sccd;
26
51d3082f 27static void udbg_scc_putc(char c)
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28{
29 if (sccc) {
30 while ((in_8(sccc) & SCC_TXRDY) == 0)
31 ;
32 out_8(sccd, c);
33 if (c == '\n')
34 udbg_scc_putc('\r');
35 }
36}
37
38static int udbg_scc_getc_poll(void)
39{
40 if (sccc) {
41 if ((in_8(sccc) & SCC_RXRDY) != 0)
42 return in_8(sccd);
43 else
44 return -1;
45 }
46 return -1;
47}
48
bb6b9b28 49static int udbg_scc_getc(void)
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50{
51 if (sccc) {
52 while ((in_8(sccc) & SCC_RXRDY) == 0)
53 ;
54 return in_8(sccd);
55 }
bb6b9b28 56 return -1;
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57}
58
59static unsigned char scc_inittab[] = {
60 13, 0, /* set baud rate divisor */
61 12, 0,
62 14, 1, /* baud rate gen enable, src=rtxc */
63 11, 0x50, /* clocks = br gen */
64 5, 0xea, /* tx 8 bits, assert DTR & RTS */
65 4, 0x46, /* x16 clock, 1 stop */
66 3, 0xc1, /* rx enable, 8 bits */
67};
68
51d3082f 69void udbg_scc_init(int force_scc)
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70{
71 u32 *reg;
72 unsigned long addr;
51d3082f
BH
73 struct device_node *stdout = NULL, *escc = NULL, *macio = NULL;
74 struct device_node *ch, *ch_def = NULL, *ch_a = NULL;
75 char *path;
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76 int i, x;
77
51d3082f
BH
78 escc = of_find_node_by_name(NULL, "escc");
79 if (escc == NULL)
80 goto bail;
81 macio = of_get_parent(escc);
82 if (macio == NULL)
83 goto bail;
84 path = (char *)get_property(of_chosen, "linux,stdout-path", NULL);
85 if (path != NULL)
86 stdout = of_find_node_by_path(path);
87 for (ch = NULL; (ch = of_get_next_child(escc, ch)) != NULL;) {
88 if (ch == stdout)
89 ch_def = of_node_get(ch);
90 if (strcmp(ch->name, "ch-a") == 0)
91 ch_a = of_node_get(ch);
92 }
93 if (ch_def == NULL && !force_scc)
94 goto bail;
95
96 ch = ch_def ? ch_def : ch_a;
7f853352 97
7f853352 98 /* Get address within mac-io ASIC */
51d3082f 99 reg = (u32 *)get_property(escc, "reg", NULL);
7f853352 100 if (reg == NULL)
51d3082f 101 goto bail;
7f853352 102 addr = reg[0];
51d3082f 103
7f853352 104 /* Get address of mac-io PCI itself */
51d3082f 105 reg = (u32 *)get_property(macio, "assigned-addresses", NULL);
7f853352 106 if (reg == NULL)
51d3082f 107 goto bail;
7f853352 108 addr += reg[2];
51d3082f
BH
109
110 /* Lock the serial port */
111 pmac_call_feature(PMAC_FTR_SCC_ENABLE, ch,
112 PMAC_SCC_ASYNC | PMAC_SCC_FLAG_XMON, 1);
113
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114
115 /* Setup for 57600 8N1 */
51d3082f
BH
116 if (ch == ch_a)
117 addr += 0x20;
af308377 118 sccc = ioremap(addr & PAGE_MASK, PAGE_SIZE) ;
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119 sccc += addr & ~PAGE_MASK;
120 sccd = sccc + 0x10;
121
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122 mb();
123
124 for (i = 20000; i != 0; --i)
125 x = in_8(sccc);
126 out_8(sccc, 0x09); /* reset A or B side */
127 out_8(sccc, 0xc0);
128 for (i = 0; i < sizeof(scc_inittab); ++i)
129 out_8(sccc, scc_inittab[i]);
130
c8f1c8be
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131 udbg_putc = udbg_scc_putc;
132 udbg_getc = udbg_scc_getc;
133 udbg_getc_poll = udbg_scc_getc_poll;
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134
135 udbg_puts("Hello World !\n");
51d3082f
BH
136
137 bail:
138 of_node_put(macio);
139 of_node_put(escc);
140 of_node_put(stdout);
141 of_node_put(ch_def);
142 of_node_put(ch_a);
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143}
144
51d3082f
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145#ifdef CONFIG_PPC64
146static void udbg_real_scc_putc(char c)
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147{
148 while ((real_readb(sccc) & SCC_TXRDY) == 0)
149 ;
150 real_writeb(c, sccd);
151 if (c == '\n')
152 udbg_real_scc_putc('\r');
153}
154
296167ae 155void __init udbg_init_pmac_realmode(void)
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156{
157 sccc = (volatile u8 __iomem *)0x80013020ul;
158 sccd = (volatile u8 __iomem *)0x80013030ul;
159
c8f1c8be
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160 udbg_putc = udbg_real_scc_putc;
161 udbg_getc = NULL;
162 udbg_getc_poll = NULL;
7f853352 163}
51d3082f 164#endif /* CONFIG_PPC64 */