arch/sparc/prom/bootstr_64.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * bootstr.c:  Boot string/argument acquisition from the PROM.
   4  *
   5  * Copyright(C) 1995 David S. Miller (davem@caip.rutgers.edu)
   6  * Copyright(C) 1996,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   7  */
   8
   9 #include <linux/string.h>
  10 #include <linux/init.h>
  11 #include <asm/oplib.h>
  12
  13 /* WARNING: The boot loader knows that these next three variables come one right
  14  *          after another in the .data section.  Do not move this stuff into
  15  *          the .bss section or it will break things.
  16  */
  17
  18 /* We limit BARG_LEN to 1024 because this is the size of the
  19  * 'barg_out' command line buffer in the SILO bootloader.
  20  */
  21 #define BARG_LEN 1024
  22 struct {
  23         int bootstr_len;
  24         int bootstr_valid;
  25         char bootstr_buf[BARG_LEN];
  26 } bootstr_info = {
  27         .bootstr_len = BARG_LEN,
  28 #ifdef CONFIG_CMDLINE
  29         .bootstr_valid = 1,
  30         .bootstr_buf = CONFIG_CMDLINE,
  31 #endif
  32 };
  33
  34 char * __init
  35 prom_getbootargs(void)
  36 {
  37         /* This check saves us from a panic when bootfd patches args. */
  38         if (bootstr_info.bootstr_valid)
  39                 return bootstr_info.bootstr_buf;
  40         prom_getstring(prom_chosen_node, "bootargs",
  41                        bootstr_info.bootstr_buf, BARG_LEN);
  42         bootstr_info.bootstr_valid = 1;
  43         return bootstr_info.bootstr_buf;
  44 }