1 /*
2 * Copyright (C) Paul Mackerras 1997.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 */
9 #include <stddef.h>
10 #include "types.h"
11 #include "elf.h"
12 #include "string.h"
13 #include "stdio.h"
14 #include "page.h"
15 #include "ops.h"
16
17 #include "of.h"
18
19 typedef u32 prom_arg_t;
20
21 /* The following structure is used to communicate with open firmware.
22 * All arguments in and out are in big endian format. */
23 struct prom_args {
24 __be32 service; /* Address of service name string. */
25 __be32 nargs; /* Number of input arguments. */
26 __be32 nret; /* Number of output arguments. */
27 __be32 args[10]; /* Input/output arguments. */
28 };
29
30 #ifdef __powerpc64__
31 extern int prom(void *);
32 #else
33 static int (*prom) (void *);
34 #endif
35
of_init(void * promptr)36 void of_init(void *promptr)
37 {
38 #ifndef __powerpc64__
39 prom = (int (*)(void *))promptr;
40 #endif
41 }
42
43 #define ADDR(x) (u32)(unsigned long)(x)
44
of_call_prom(const char * service,int nargs,int nret,...)45 int of_call_prom(const char *service, int nargs, int nret, ...)
46 {
47 int i;
48 struct prom_args args;
49 va_list list;
50
51 args.service = cpu_to_be32(ADDR(service));
52 args.nargs = cpu_to_be32(nargs);
53 args.nret = cpu_to_be32(nret);
54
55 va_start(list, nret);
56 for (i = 0; i < nargs; i++)
57 args.args[i] = cpu_to_be32(va_arg(list, prom_arg_t));
58 va_end(list);
59
60 for (i = 0; i < nret; i++)
61 args.args[nargs+i] = 0;
62
63 if (prom(&args) < 0)
64 return PROM_ERROR;
65
66 return (nret > 0) ? be32_to_cpu(args.args[nargs]) : 0;
67 }
68
of_call_prom_ret(const char * service,int nargs,int nret,prom_arg_t * rets,...)69 static int of_call_prom_ret(const char *service, int nargs, int nret,
70 prom_arg_t *rets, ...)
71 {
72 int i;
73 struct prom_args args;
74 va_list list;
75
76 args.service = cpu_to_be32(ADDR(service));
77 args.nargs = cpu_to_be32(nargs);
78 args.nret = cpu_to_be32(nret);
79
80 va_start(list, rets);
81 for (i = 0; i < nargs; i++)
82 args.args[i] = cpu_to_be32(va_arg(list, prom_arg_t));
83 va_end(list);
84
85 for (i = 0; i < nret; i++)
86 args.args[nargs+i] = 0;
87
88 if (prom(&args) < 0)
89 return PROM_ERROR;
90
91 if (rets != NULL)
92 for (i = 1; i < nret; ++i)
93 rets[i-1] = be32_to_cpu(args.args[nargs+i]);
94
95 return (nret > 0) ? be32_to_cpu(args.args[nargs]) : 0;
96 }
97
98 /* returns true if s2 is a prefix of s1 */
string_match(const char * s1,const char * s2)99 static int string_match(const char *s1, const char *s2)
100 {
101 for (; *s2; ++s2)
102 if (*s1++ != *s2)
103 return 0;
104 return 1;
105 }
106
107 /*
108 * Older OF's require that when claiming a specific range of addresses,
109 * we claim the physical space in the /memory node and the virtual
110 * space in the chosen mmu node, and then do a map operation to
111 * map virtual to physical.
112 */
113 static int need_map = -1;
114 static ihandle chosen_mmu;
115 static ihandle memory;
116
check_of_version(void)117 static int check_of_version(void)
118 {
119 phandle oprom, chosen;
120 char version[64];
121
122 oprom = of_finddevice("/openprom");
123 if (oprom == (phandle) -1)
124 return 0;
125 if (of_getprop(oprom, "model", version, sizeof(version)) <= 0)
126 return 0;
127 version[sizeof(version)-1] = 0;
128 printf("OF version = '%s'\r\n", version);
129 if (!string_match(version, "Open Firmware, 1.")
130 && !string_match(version, "FirmWorks,3."))
131 return 0;
132 chosen = of_finddevice("/chosen");
133 if (chosen == (phandle) -1) {
134 chosen = of_finddevice("/chosen@0");
135 if (chosen == (phandle) -1) {
136 printf("no chosen\n");
137 return 0;
138 }
139 }
140 if (of_getprop(chosen, "mmu", &chosen_mmu, sizeof(chosen_mmu)) <= 0) {
141 printf("no mmu\n");
142 return 0;
143 }
144 memory = of_call_prom("open", 1, 1, "/memory");
145 if (memory == PROM_ERROR) {
146 memory = of_call_prom("open", 1, 1, "/memory@0");
147 if (memory == PROM_ERROR) {
148 printf("no memory node\n");
149 return 0;
150 }
151 }
152 printf("old OF detected\r\n");
153 return 1;
154 }
155
of_claim(unsigned long virt,unsigned long size,unsigned long align)156 unsigned int of_claim(unsigned long virt, unsigned long size,
157 unsigned long align)
158 {
159 int ret;
160 prom_arg_t result;
161
162 if (need_map < 0)
163 need_map = check_of_version();
164 if (align || !need_map)
165 return of_call_prom("claim", 3, 1, virt, size, align);
166
167 ret = of_call_prom_ret("call-method", 5, 2, &result, "claim", memory,
168 align, size, virt);
169 if (ret != 0 || result == -1)
170 return -1;
171 ret = of_call_prom_ret("call-method", 5, 2, &result, "claim", chosen_mmu,
172 align, size, virt);
173 /* 0x12 == coherent + read/write */
174 ret = of_call_prom("call-method", 6, 1, "map", chosen_mmu,
175 0x12, size, virt, virt);
176 return virt;
177 }
178
of_vmlinux_alloc(unsigned long size)179 void *of_vmlinux_alloc(unsigned long size)
180 {
181 unsigned long start = (unsigned long)_start, end = (unsigned long)_end;
182 unsigned long addr;
183 void *p;
184
185 /* With some older POWER4 firmware we need to claim the area the kernel
186 * will reside in. Newer firmwares don't need this so we just ignore
187 * the return value.
188 */
189 addr = (unsigned long) of_claim(start, end - start, 0);
190 printf("Trying to claim from 0x%lx to 0x%lx (0x%lx) got %lx\r\n",
191 start, end, end - start, addr);
192
193 p = malloc(size);
194 if (!p)
195 fatal("Can't allocate memory for kernel image!\n\r");
196
197 return p;
198 }
199
of_exit(void)200 void of_exit(void)
201 {
202 of_call_prom("exit", 0, 0);
203 }
204
205 /*
206 * OF device tree routines
207 */
of_finddevice(const char * name)208 void *of_finddevice(const char *name)
209 {
210 return (void *) (unsigned long) of_call_prom("finddevice", 1, 1, name);
211 }
212
of_getprop(const void * phandle,const char * name,void * buf,const int buflen)213 int of_getprop(const void *phandle, const char *name, void *buf,
214 const int buflen)
215 {
216 return of_call_prom("getprop", 4, 1, phandle, name, buf, buflen);
217 }
218
of_setprop(const void * phandle,const char * name,const void * buf,const int buflen)219 int of_setprop(const void *phandle, const char *name, const void *buf,
220 const int buflen)
221 {
222 return of_call_prom("setprop", 4, 1, phandle, name, buf, buflen);
223 }
224