1 /* 2 * uboot.c -- uboot arguments support 3 * 4 * This file is subject to the terms and conditions of the GNU General Public 5 * License. See the file COPYING in the main directory of this archive 6 * for more details. 7 */ 8 9 #include <linux/kernel.h> 10 #include <linux/sched.h> 11 #include <linux/delay.h> 12 #include <linux/interrupt.h> 13 #include <linux/fb.h> 14 #include <linux/module.h> 15 #include <linux/mm.h> 16 #include <linux/console.h> 17 #include <linux/errno.h> 18 #include <linux/string.h> 19 #include <linux/memblock.h> 20 #include <linux/seq_file.h> 21 #include <linux/init.h> 22 #include <linux/initrd.h> 23 #include <linux/root_dev.h> 24 #include <linux/rtc.h> 25 26 #include <asm/setup.h> 27 #include <asm/irq.h> 28 #include <asm/machdep.h> 29 #include <asm/sections.h> 30 #include <asm/bootinfo.h> 31 32 /* 33 * parse_uboot_commandline 34 * 35 * Copies u-boot commandline arguments and store them in the proper linux 36 * variables. 37 * 38 * Assumes: 39 * _init_sp global contains the address in the stack pointer when the 40 * kernel starts (see head.S::_start) 41 * 42 * U-Boot calling convention: 43 * (*kernel) (kbd, initrd_start, initrd_end, cmd_start, cmd_end); 44 * 45 * _init_sp can be parsed as such 46 * 47 * _init_sp+00 = u-boot cmd after jsr into kernel (skip) 48 * _init_sp+04 = &kernel board_info (residual data) 49 * _init_sp+08 = &initrd_start 50 * _init_sp+12 = &initrd_end 51 * _init_sp+16 = &cmd_start 52 * _init_sp+20 = &cmd_end 53 * 54 * This also assumes that the memory locations pointed to are still 55 * unmodified. U-boot places them near the end of external SDRAM. 56 * 57 * Argument(s): 58 * commandp = the linux commandline arg container to fill. 59 * size = the sizeof commandp. 60 * 61 * Returns: 62 */ 63 static void __init parse_uboot_commandline(char *commandp, int size) 64 { 65 extern unsigned long _init_sp; 66 unsigned long *sp; 67 unsigned long uboot_cmd_start, uboot_cmd_end; 68 #if defined(CONFIG_BLK_DEV_INITRD) 69 unsigned long uboot_initrd_start, uboot_initrd_end; 70 #endif /* if defined(CONFIG_BLK_DEV_INITRD) */ 71 72 sp = (unsigned long *)_init_sp; 73 uboot_cmd_start = sp[4]; 74 uboot_cmd_end = sp[5]; 75 76 if (uboot_cmd_start && uboot_cmd_end) 77 strncpy(commandp, (const char *)uboot_cmd_start, size); 78 79 #if defined(CONFIG_BLK_DEV_INITRD) 80 uboot_initrd_start = sp[2]; 81 uboot_initrd_end = sp[3]; 82 83 if (uboot_initrd_start && uboot_initrd_end && 84 (uboot_initrd_end > uboot_initrd_start)) { 85 initrd_start = uboot_initrd_start; 86 initrd_end = uboot_initrd_end; 87 ROOT_DEV = Root_RAM0; 88 pr_info("initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end); 89 } 90 #endif /* if defined(CONFIG_BLK_DEV_INITRD) */ 91 } 92 93 __init void process_uboot_commandline(char *commandp, int size) 94 { 95 int len, n; 96 97 n = strnlen(commandp, size); 98 commandp += n; 99 len = size - n; 100 if (len) { 101 /* Add the whitespace separator */ 102 *commandp++ = ' '; 103 len--; 104 } 105 106 parse_uboot_commandline(commandp, len); 107 commandp[len - 1] = 0; 108 } 109