1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0 2*4882a593Smuzhiyun /* 3*4882a593Smuzhiyun * bootstr.c: Boot string/argument acquisition from the PROM. 4*4882a593Smuzhiyun * 5*4882a593Smuzhiyun * Copyright(C) 1995 David S. Miller (davem@caip.rutgers.edu) 6*4882a593Smuzhiyun * Copyright(C) 1996,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz) 7*4882a593Smuzhiyun */ 8*4882a593Smuzhiyun 9*4882a593Smuzhiyun #include <linux/string.h> 10*4882a593Smuzhiyun #include <linux/init.h> 11*4882a593Smuzhiyun #include <asm/oplib.h> 12*4882a593Smuzhiyun 13*4882a593Smuzhiyun /* WARNING: The boot loader knows that these next three variables come one right 14*4882a593Smuzhiyun * after another in the .data section. Do not move this stuff into 15*4882a593Smuzhiyun * the .bss section or it will break things. 16*4882a593Smuzhiyun */ 17*4882a593Smuzhiyun 18*4882a593Smuzhiyun /* We limit BARG_LEN to 1024 because this is the size of the 19*4882a593Smuzhiyun * 'barg_out' command line buffer in the SILO bootloader. 20*4882a593Smuzhiyun */ 21*4882a593Smuzhiyun #define BARG_LEN 1024 22*4882a593Smuzhiyun struct { 23*4882a593Smuzhiyun int bootstr_len; 24*4882a593Smuzhiyun int bootstr_valid; 25*4882a593Smuzhiyun char bootstr_buf[BARG_LEN]; 26*4882a593Smuzhiyun } bootstr_info = { 27*4882a593Smuzhiyun .bootstr_len = BARG_LEN, 28*4882a593Smuzhiyun #ifdef CONFIG_CMDLINE 29*4882a593Smuzhiyun .bootstr_valid = 1, 30*4882a593Smuzhiyun .bootstr_buf = CONFIG_CMDLINE, 31*4882a593Smuzhiyun #endif 32*4882a593Smuzhiyun }; 33*4882a593Smuzhiyun 34*4882a593Smuzhiyun char * __init prom_getbootargs(void)35*4882a593Smuzhiyunprom_getbootargs(void) 36*4882a593Smuzhiyun { 37*4882a593Smuzhiyun /* This check saves us from a panic when bootfd patches args. */ 38*4882a593Smuzhiyun if (bootstr_info.bootstr_valid) 39*4882a593Smuzhiyun return bootstr_info.bootstr_buf; 40*4882a593Smuzhiyun prom_getstring(prom_chosen_node, "bootargs", 41*4882a593Smuzhiyun bootstr_info.bootstr_buf, BARG_LEN); 42*4882a593Smuzhiyun bootstr_info.bootstr_valid = 1; 43*4882a593Smuzhiyun return bootstr_info.bootstr_buf; 44*4882a593Smuzhiyun } 45