aboutsummaryrefslogtreecommitdiff
path: root/arch/powerpc/boot/prom.c
blob: fa0057736f6b391bfc5fa96bfd5fdbebc217754d (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
/*
 * Copyright (C) Paul Mackerras 1997.
 *
 * 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 <stdarg.h>
#include <stddef.h>
#include "string.h"
#include "stdio.h"
#include "prom.h"

int (*prom)(void *);
phandle chosen_handle;
ihandle stdout;

int call_prom(const char *service, int nargs, int nret, ...)
{
	int i;
	struct prom_args {
		const char *service;
		int nargs;
		int nret;
		unsigned int args[12];
	} args;
	va_list list;

	args.service = service;
	args.nargs = nargs;
	args.nret = nret;

	va_start(list, nret);
	for (i = 0; i < nargs; i++)
		args.args[i] = va_arg(list, unsigned int);
	va_end(list);

	for (i = 0; i < nret; i++)
		args.args[nargs+i] = 0;

	if (prom(&args) < 0)
		return -1;

	return (nret > 0)? args.args[nargs]: 0;
}

int call_prom_ret(const char *service, int nargs, int nret,
		  unsigned int *rets, ...)
{
	int i;
	struct prom_args {
		const char *service;
		int nargs;
		int nret;
		unsigned int args[12];
	} args;
	va_list list;

	args.service = service;
	args.nargs = nargs;
	args.nret = nret;

	va_start(list, rets);
	for (i = 0; i < nargs; i++)
		args.args[i] = va_arg(list, unsigned int);
	va_end(list);

	for (i = 0; i < nret; i++)
		args.args[nargs+i] = 0;

	if (prom(&args) < 0)
		return -1;

	if (rets != (void *) 0)
		for (i = 1; i < nret; ++i)
			rets[i-1] = args.args[nargs+i];

	return (nret > 0)? args.args[nargs]: 0;
}

int write(void *handle, void *ptr, int nb)
{
	return call_prom("write", 3, 1, handle, ptr, nb);
}

/*
 * Older OF's require that when claiming a specific range of addresses,
 * we claim the physical space in the /memory node and the virtual
 * space in the chosen mmu node, and then do a map operation to
 * map virtual to physical.
 */
static int need_map = -1;
static ihandle chosen_mmu;
static phandle memory;

/* returns true if s2 is a prefix of s1 */
static int string_match(const char *s1, const char *s2)
{
	for (; *s2; ++s2)
		if (*s1++ != *s2)
			return 0;
	return 1;
}

static int check_of_version(void)
{
	phandle oprom, chosen;
	char version[64];

	oprom = finddevice("/openprom");
	if (oprom == (phandle) -1)
		return 0;
	if (getprop(oprom, "model", version, sizeof(version)) <= 0)
		return 0;
	version[sizeof(version)-1] = 0;
	printf("OF version = '%s'\r\n", version);
	if (!string_match(version, "Open Firmware, 1.")
	    && !string_match(version, "FirmWorks,3."))
		return 0;
	chosen = finddevice("/chosen");
	if (chosen == (phandle) -1) {
		chosen = finddevice("/chosen@0");
		if (chosen == (phandle) -1) {
			printf("no chosen\n");
			return 0;
		}
	}
	if (getprop(chosen, "mmu", &chosen_mmu, sizeof(chosen_mmu)) <= 0) {
		printf("no mmu\n");
		return 0;
	}
	memory = (ihandle) call_prom("open", 1, 1, "/memory");
	if (memory == (ihandle) -1) {
		memory = (ihandle) call_prom("open", 1, 1, "/memory@0");
		if (memory == (ihandle) -1) {
			printf("no memory node\n");
			return 0;
		}
	}
	printf("old OF detected\r\n");
	return 1;
}

void *claim(unsigned long virt, unsigned long size, unsigned long align)
{
	int ret;
	unsigned int result;

	if (need_map < 0)
		need_map = check_of_version();
	if (align || !need_map)
		return (void *) call_prom("claim", 3, 1, virt, size, align);
	
	ret = call_prom_ret("call-method", 5, 2, &result, "claim", memory,
			    align, size, virt);
	if (ret != 0 || result == -1)
		return (void *) -1;
	ret = call_prom_ret("call-method", 5, 2, &result, "claim", chosen_mmu,
			    align, size, virt);
	/* 0x12 == coherent + read/write */
	ret = call_prom("call-method", 6, 1, "map", chosen_mmu,
			0x12, size, virt, virt);
	return (void *) virt;
}