xref: /linux/arch/mips/boot/compressed/decompress.c (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
1 /*
2  * Copyright 2001 MontaVista Software Inc.
3  * Author: Matt Porter <mporter@mvista.com>
4  *
5  * Copyright (C) 2009 Lemote, Inc.
6  * Author: Wu Zhangjin <wuzhangjin@gmail.com>
7  *
8  * This program is free software; you can redistribute	it and/or modify it
9  * under  the terms of	the GNU General	 Public License as published by the
10  * Free Software Foundation;  either version 2 of the  License, or (at your
11  * option) any later version.
12  */
13 
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/string.h>
17 
18 #include <asm/addrspace.h>
19 
20 /*
21  * These two variables specify the free mem region
22  * that can be used for temporary malloc area
23  */
24 unsigned long free_mem_ptr;
25 unsigned long free_mem_end_ptr;
26 
27 /* The linker tells us where the image is. */
28 extern unsigned char __image_begin, __image_end;
29 
30 /* debug interfaces  */
31 #ifdef CONFIG_DEBUG_ZBOOT
32 extern void puts(const char *s);
33 extern void puthex(unsigned long long val);
34 #else
35 #define puts(s) do {} while (0)
36 #define puthex(val) do {} while (0)
37 #endif
38 
39 void error(char *x)
40 {
41 	puts("\n\n");
42 	puts(x);
43 	puts("\n\n -- System halted");
44 
45 	while (1)
46 		;	/* Halt */
47 }
48 
49 /* activate the code for pre-boot environment */
50 #define STATIC static
51 
52 #ifdef CONFIG_KERNEL_GZIP
53 #include "../../../../lib/decompress_inflate.c"
54 #endif
55 
56 #ifdef CONFIG_KERNEL_BZIP2
57 #include "../../../../lib/decompress_bunzip2.c"
58 #endif
59 
60 #ifdef CONFIG_KERNEL_LZ4
61 #include "../../../../lib/decompress_unlz4.c"
62 #endif
63 
64 #ifdef CONFIG_KERNEL_LZMA
65 #include "../../../../lib/decompress_unlzma.c"
66 #endif
67 
68 #ifdef CONFIG_KERNEL_LZO
69 #include "../../../../lib/decompress_unlzo.c"
70 #endif
71 
72 #ifdef CONFIG_KERNEL_XZ
73 #include "../../../../lib/decompress_unxz.c"
74 #endif
75 
76 unsigned long __stack_chk_guard;
77 
78 void __stack_chk_guard_setup(void)
79 {
80 	__stack_chk_guard = 0x000a0dff;
81 }
82 
83 void __stack_chk_fail(void)
84 {
85 	error("stack-protector: Kernel stack is corrupted\n");
86 }
87 
88 void decompress_kernel(unsigned long boot_heap_start)
89 {
90 	unsigned long zimage_start, zimage_size;
91 
92 	__stack_chk_guard_setup();
93 
94 	zimage_start = (unsigned long)(&__image_begin);
95 	zimage_size = (unsigned long)(&__image_end) -
96 	    (unsigned long)(&__image_begin);
97 
98 	puts("zimage at:     ");
99 	puthex(zimage_start);
100 	puts(" ");
101 	puthex(zimage_size + zimage_start);
102 	puts("\n");
103 
104 	/* This area are prepared for mallocing when decompressing */
105 	free_mem_ptr = boot_heap_start;
106 	free_mem_end_ptr = boot_heap_start + BOOT_HEAP_SIZE;
107 
108 	/* Display standard Linux/MIPS boot prompt */
109 	puts("Uncompressing Linux at load address ");
110 	puthex(VMLINUX_LOAD_ADDRESS_ULL);
111 	puts("\n");
112 
113 	/* Decompress the kernel with according algorithm */
114 	__decompress((char *)zimage_start, zimage_size, 0, 0,
115 		   (void *)VMLINUX_LOAD_ADDRESS_ULL, 0, 0, error);
116 
117 	/* FIXME: should we flush cache here? */
118 	puts("Now, booting the kernel...\n");
119 }
120