arch/sparc/prom/bootstr.c

   1 /* $Id: bootstr.c,v 1.18 1999/08/31 06:54:45 davem Exp $
   2  * bootstr.c:  Boot string/argument acquisition from the PROM.
   3  *
   4  * Copyright(C) 1995 David S. Miller (davem@caip.rutgers.edu)
   5  */
   6
   7 #include <linux/config.h>
   8 #include <linux/string.h>
   9 #include <asm/oplib.h>
  10 #include <asm/sun4prom.h>
  11 #include <linux/init.h>
  12
  13 #define BARG_LEN  256
  14 static char barg_buf[BARG_LEN] = { 0 };
  15 static char fetched __initdata = 0;
  16
  17 extern linux_sun4_romvec *sun4_romvec;
  18
  19 char * __init
  20 prom_getbootargs(void)
  21 {
  22         int iter;
  23         char *cp, *arg;
  24
  25         /* This check saves us from a panic when bootfd patches args. */
  26         if (fetched) {
  27                 return barg_buf;
  28         }
  29
  30         switch(prom_vers) {
  31         case PROM_V0:
  32         case PROM_SUN4:
  33                 cp = barg_buf;
  34                 /* Start from 1 and go over fd(0,0,0)kernel */
  35                 for(iter = 1; iter < 8; iter++) {
  36                         arg = (*(romvec->pv_v0bootargs))->argv[iter];
  37                         if(arg == 0) break;
  38                         while(*arg != 0) {
  39                                 /* Leave place for space and null. */
  40                                 if(cp >= barg_buf + BARG_LEN-2){
  41                                         /* We might issue a warning here. */
  42                                         break;
  43                                 }
  44                                 *cp++ = *arg++;
  45                         }
  46                         *cp++ = ' ';
  47                 }
  48                 *cp = 0;
  49                 break;
  50         case PROM_V2:
  51         case PROM_V3:
  52                 /*
  53                  * V3 PROM cannot supply as with more than 128 bytes
  54                  * of an argument. But a smart bootstrap loader can.
  55                  */
  56                 strncpy(barg_buf, *romvec->pv_v2bootargs.bootargs, BARG_LEN-1);
  57                 break;
  58         case PROM_AP1000:
  59 #if CONFIG_AP1000
  60                 ap_getbootargs(barg_buf, BARG_LEN);
  61                 break;
  62 #endif
  63         default:
  64                 break;
  65         }
  66
  67         fetched = 1;
  68         return barg_buf;
  69 }