summaryrefslogtreecommitdiffstats
path: root/kernel/arch/powerpc/boot/oflib.c
blob: 46c98a47d9493a7ae54940070cb7ceb0cc716a59 (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
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
/*
 * 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 <stddef.h>
#include "types.h"
#include "elf.h"
#include "string.h"
#include "stdio.h"
#include "page.h"
#include "ops.h"

#include "of.h"

typedef u32 prom_arg_t;

/* The following structure is used to communicate with open firmware.
 * All arguments in and out are in big endian format. */
struct prom_args {
	__be32 service;	/* Address of service name string. */
	__be32 nargs;	/* Number of input arguments. */
	__be32 nret;	/* Number of output arguments. */
	__be32 args[10];	/* Input/output arguments. */
};

#ifdef __powerpc64__
extern int prom(void *);
#else
static int (*prom) (void *);
#endif

void of_init(void *promptr)
{
#ifndef __powerpc64__
	prom = (int (*)(void *))promptr;
#endif
}

#define ADDR(x)		(u32)(unsigned long)(x)

int of_call_prom(const char *service, int nargs, int nret, ...)
{
	int i;
	struct prom_args args;
	va_list list;

	args.service = cpu_to_be32(ADDR(service));
	args.nargs = cpu_to_be32(nargs);
	args.nret = cpu_to_be32(nret);

	va_start(list, nret);
	for (i = 0; i < nargs; i++)
		args.args[i] = cpu_to_be32(va_arg(list, prom_arg_t));
	va_end(list);

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

	if (prom(&args) < 0)
		return PROM_ERROR;

	return (nret > 0) ? be32_to_cpu(args.args[nargs]) : 0;
}

static int of_call_prom_ret(const char *service, int nargs, int nret,
			    prom_arg_t *rets, ...)
{
	int i;
	struct prom_args args;
	va_list list;

	args.service = cpu_to_be32(ADDR(service));
	args.nargs = cpu_to_be32(nargs);
	args.nret = cpu_to_be32(nret);

	va_start(list, rets);
	for (i = 0; i < nargs; i++)
		args.args[i] = cpu_to_be32(va_arg(list, prom_arg_t));
	va_end(list);

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

	if (prom(&args) < 0)
		return PROM_ERROR;

	if (rets != NULL)
		for (i = 1; i < nret; ++i)
			rets[i-1] = be32_to_cpu(args.args[nargs+i]);

	return (nret > 0) ? be32_to_cpu(args.args[nargs]) : 0;
}

/* 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;
}

/*
 * 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 ihandle memory;

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

	oprom = of_finddevice("/openprom");
	if (oprom == (phandle) -1)
		return 0;
	if (of_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 = of_finddevice("/chosen");
	if (chosen == (phandle) -1) {
		chosen = of_finddevice("/chosen@0");
		if (chosen == (phandle) -1) {
			printf("no chosen\n");
			return 0;
		}
	}
	if (of_getprop(chosen, "mmu", &chosen_mmu, sizeof(chosen_mmu)) <= 0) {
		printf("no mmu\n");
		return 0;
	}
	memory = of_call_prom("open", 1, 1, "/memory");
	if (memory == PROM_ERROR) {
		memory = of_call_prom("open", 1, 1, "/memory@0");
		if (memory == PROM_ERROR) {
			printf("no memory node\n");
			return 0;
		}
	}
	printf("old OF detected\r\n");
	return 1;
}

unsigned int of_claim(unsigned long virt, unsigned long size,
		      unsigned long align)
{
	int ret;
	prom_arg_t result;

	if (need_map < 0)
		need_map = check_of_version();
	if (align || !need_map)
		return of_call_prom("claim", 3, 1, virt, size, align);

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

void *of_vmlinux_alloc(unsigned long size)
{
	unsigned long start = (unsigned long)_start, end = (unsigned long)_end;
	unsigned long addr;
	void *p;

	/* With some older POWER4 firmware we need to claim the area the kernel
	 * will reside in.  Newer firmwares don't need this so we just ignore
	 * the return value.
	 */
	addr = (unsigned long) of_claim(start, end - start, 0);
	printf("Trying to claim from 0x%lx to 0x%lx (0x%lx) got %lx\r\n",
	       start, end, end - start, addr);

	p = malloc(size);
	if (!p)
		fatal("Can't allocate memory for kernel image!\n\r");

	return p;
}

void of_exit(void)
{
	of_call_prom("exit", 0, 0);
}

/*
 * OF device tree routines
 */
void *of_finddevice(const char *name)
{
	return (void *) (unsigned long) of_call_prom("finddevice", 1, 1, name);
}

int of_getprop(const void *phandle, const char *name, void *buf,
	       const int buflen)
{
	return of_call_prom("getprop", 4, 1, phandle, name, buf, buflen);
}

int of_setprop(const void *phandle, const char *name, const void *buf,
	       const int buflen)
{
	return of_call_prom("setprop", 4, 1, phandle, name, buf, buflen);
}