arch/sparc/prom/bootstr_64.c

   1 /*
   2  * bootstr.c:  Boot string/argument acquisition from the PROM.
   3  *
   4  * Copyright(C) 1995 David S. Miller (davem@caip.rutgers.edu)
   5  * Copyright(C) 1996,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   6  */
   7
   8 #include <linux/string.h>
   9 #include <linux/init.h>
  10 #include <asm/oplib.h>
  11
  12 /* WARNING: The boot loader knows that these next three variables come one right
  13  *          after another in the .data section.  Do not move this stuff into
  14  *          the .bss section or it will break things.
  15  */
  16
  17 /* We limit BARG_LEN to 1024 because this is the size of the
  18  * 'barg_out' command line buffer in the SILO bootloader.
  19  */
  20 #define BARG_LEN 1024
  21 struct {
  22         int bootstr_len;
  23         int bootstr_valid;
  24         char bootstr_buf[BARG_LEN];
  25 } bootstr_info = {
  26         .bootstr_len = BARG_LEN,
  27 #ifdef CONFIG_CMDLINE
  28         .bootstr_valid = 1,
  29         .bootstr_buf = CONFIG_CMDLINE,
  30 #endif
  31 };
  32
  33 char * __init
  34 prom_getbootargs(void)
  35 {
  36         /* This check saves us from a panic when bootfd patches args. */
  37         if (bootstr_info.bootstr_valid)
  38                 return bootstr_info.bootstr_buf;
  39         prom_getstring(prom_chosen_node, "bootargs",
  40                        bootstr_info.bootstr_buf, BARG_LEN);
  41         bootstr_info.bootstr_valid = 1;
  42         return bootstr_info.bootstr_buf;
  43 }