arch/powerpc/boot/oflib.c

   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 static int (*prom) (void *);
  20
  21 void of_init(void *promptr)
  22 {
  23         prom = (int (*)(void *))promptr;
  24 }
  25
  26 int of_call_prom(const char *service, int nargs, int nret, ...)
  27 {
  28         int i;
  29         struct prom_args {
  30                 const char *service;
  31                 int nargs;
  32                 int nret;
  33                 unsigned int args[12];
  34         } args;
  35         va_list list;
  36
  37         args.service = service;
  38         args.nargs = nargs;
  39         args.nret = nret;
  40
  41         va_start(list, nret);
  42         for (i = 0; i < nargs; i++)
  43                 args.args[i] = va_arg(list, unsigned int);
  44         va_end(list);
  45
  46         for (i = 0; i < nret; i++)
  47                 args.args[nargs+i] = 0;
  48
  49         if (prom(&args) < 0)
  50                 return -1;
  51
  52         return (nret > 0)? args.args[nargs]: 0;
  53 }
  54
  55 static int of_call_prom_ret(const char *service, int nargs, int nret,
  56                             unsigned int *rets, ...)
  57 {
  58         int i;
  59         struct prom_args {
  60                 const char *service;
  61                 int nargs;
  62                 int nret;
  63                 unsigned int args[12];
  64         } args;
  65         va_list list;
  66
  67         args.service = service;
  68         args.nargs = nargs;
  69         args.nret = nret;
  70
  71         va_start(list, rets);
  72         for (i = 0; i < nargs; i++)
  73                 args.args[i] = va_arg(list, unsigned int);
  74         va_end(list);
  75
  76         for (i = 0; i < nret; i++)
  77                 args.args[nargs+i] = 0;
  78
  79         if (prom(&args) < 0)
  80                 return -1;
  81
  82         if (rets != (void *) 0)
  83                 for (i = 1; i < nret; ++i)
  84                         rets[i-1] = args.args[nargs+i];
  85
  86         return (nret > 0)? args.args[nargs]: 0;
  87 }
  88
  89 /* returns true if s2 is a prefix of s1 */
  90 static int string_match(const char *s1, const char *s2)
  91 {
  92         for (; *s2; ++s2)
  93                 if (*s1++ != *s2)
  94                         return 0;
  95         return 1;
  96 }
  97
  98 /*
  99  * Older OF's require that when claiming a specific range of addresses,
 100  * we claim the physical space in the /memory node and the virtual
 101  * space in the chosen mmu node, and then do a map operation to
 102  * map virtual to physical.
 103  */
 104 static int need_map = -1;
 105 static ihandle chosen_mmu;
 106 static phandle memory;
 107
 108 static int check_of_version(void)
 109 {
 110         phandle oprom, chosen;
 111         char version[64];
 112
 113         oprom = of_finddevice("/openprom");
 114         if (oprom == (phandle) -1)
 115                 return 0;
 116         if (of_getprop(oprom, "model", version, sizeof(version)) <= 0)
 117                 return 0;
 118         version[sizeof(version)-1] = 0;
 119         printf("OF version = '%s'\r\n", version);
 120         if (!string_match(version, "Open Firmware, 1.")
 121             && !string_match(version, "FirmWorks,3."))
 122                 return 0;
 123         chosen = of_finddevice("/chosen");
 124         if (chosen == (phandle) -1) {
 125                 chosen = of_finddevice("/chosen@0");
 126                 if (chosen == (phandle) -1) {
 127                         printf("no chosen\n");
 128                         return 0;
 129                 }
 130         }
 131         if (of_getprop(chosen, "mmu", &chosen_mmu, sizeof(chosen_mmu)) <= 0) {
 132                 printf("no mmu\n");
 133                 return 0;
 134         }
 135         memory = (ihandle) of_call_prom("open", 1, 1, "/memory");
 136         if (memory == (ihandle) -1) {
 137                 memory = (ihandle) of_call_prom("open", 1, 1, "/memory@0");
 138                 if (memory == (ihandle) -1) {
 139                         printf("no memory node\n");
 140                         return 0;
 141                 }
 142         }
 143         printf("old OF detected\r\n");
 144         return 1;
 145 }
 146
 147 void *of_claim(unsigned long virt, unsigned long size, unsigned long align)
 148 {
 149         int ret;
 150         unsigned int result;
 151
 152         if (need_map < 0)
 153                 need_map = check_of_version();
 154         if (align || !need_map)
 155                 return (void *) of_call_prom("claim", 3, 1, virt, size, align);
 156
 157         ret = of_call_prom_ret("call-method", 5, 2, &result, "claim", memory,
 158                                align, size, virt);
 159         if (ret != 0 || result == -1)
 160                 return (void *) -1;
 161         ret = of_call_prom_ret("call-method", 5, 2, &result, "claim", chosen_mmu,
 162                                align, size, virt);
 163         /* 0x12 == coherent + read/write */
 164         ret = of_call_prom("call-method", 6, 1, "map", chosen_mmu,
 165                            0x12, size, virt, virt);
 166         return (void *) virt;
 167 }
 168
 169 void *of_vmlinux_alloc(unsigned long size)
 170 {
 171         unsigned long start = (unsigned long)_start, end = (unsigned long)_end;
 172         void *addr;
 173         void *p;
 174
 175         /* With some older POWER4 firmware we need to claim the area the kernel
 176          * will reside in.  Newer firmwares don't need this so we just ignore
 177          * the return value.
 178          */
 179         addr = of_claim(start, end - start, 0);
 180         printf("Trying to claim from 0x%lx to 0x%lx (0x%lx) got %p\r\n",
 181                start, end, end - start, addr);
 182
 183         p = malloc(size);
 184         if (!p)
 185                 fatal("Can't allocate memory for kernel image!\n\r");
 186
 187         return p;
 188 }
 189
 190 void of_exit(void)
 191 {
 192         of_call_prom("exit", 0, 0);
 193 }
 194
 195 /*
 196  * OF device tree routines
 197  */
 198 void *of_finddevice(const char *name)
 199 {
 200         return (phandle) of_call_prom("finddevice", 1, 1, name);
 201 }
 202
 203 int of_getprop(const void *phandle, const char *name, void *buf,
 204                const int buflen)
 205 {
 206         return of_call_prom("getprop", 4, 1, phandle, name, buf, buflen);
 207 }
 208
 209 int of_setprop(const void *phandle, const char *name, const void *buf,
 210                const int buflen)
 211 {
 212         return of_call_prom("setprop", 4, 1, phandle, name, buf, buflen);
 213 }