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(p: commandp, q: (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(p: commandp, maxlen: 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, size: len); |
107 | commandp[len - 1] = 0; |
108 | } |
109 | |