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 
17 #include <asm/addrspace.h>
18 
19 /*
20  * These two variables specify the free mem region
21  * that can be used for temporary malloc area
22  */
23 unsigned long free_mem_ptr;
24 unsigned long free_mem_end_ptr;
25 
26 /* The linker tells us where the image is. */
27 extern unsigned char __image_begin, __image_end;
28 
29 /* debug interfaces  */
30 extern void puts(const char *s);
31 extern void puthex(unsigned long long val);
32 
33 void error(char *x)
34 {
35 	puts("\n\n");
36 	puts(x);
37 	puts("\n\n -- System halted");
38 
39 	while (1)
40 		;	/* Halt */
41 }
42 
43 /* activate the code for pre-boot environment */
44 #define STATIC static
45 
46 #ifdef CONFIG_KERNEL_GZIP
47 #include "../../../../lib/decompress_inflate.c"
48 #endif
49 
50 #ifdef CONFIG_KERNEL_BZIP2
51 #include "../../../../lib/decompress_bunzip2.c"
52 #endif
53 
54 #ifdef CONFIG_KERNEL_LZ4
55 #include "../../../../lib/decompress_unlz4.c"
56 #endif
57 
58 #ifdef CONFIG_KERNEL_LZMA
59 #include "../../../../lib/decompress_unlzma.c"
60 #endif
61 
62 #ifdef CONFIG_KERNEL_LZO
63 #include "../../../../lib/decompress_unlzo.c"
64 #endif
65 
66 #ifdef CONFIG_KERNEL_XZ
67 #include "../../../../lib/decompress_unxz.c"
68 #endif
69 
70 unsigned long __stack_chk_guard;
71 
72 void __stack_chk_guard_setup(void)
73 {
74 	__stack_chk_guard = 0x000a0dff;
75 }
76 
77 void __stack_chk_fail(void)
78 {
79 	error("stack-protector: Kernel stack is corrupted\n");
80 }
81 
82 void decompress_kernel(unsigned long boot_heap_start)
83 {
84 	unsigned long zimage_start, zimage_size;
85 
86 	__stack_chk_guard_setup();
87 
88 	zimage_start = (unsigned long)(&__image_begin);
89 	zimage_size = (unsigned long)(&__image_end) -
90 	    (unsigned long)(&__image_begin);
91 
92 	puts("zimage at:     ");
93 	puthex(zimage_start);
94 	puts(" ");
95 	puthex(zimage_size + zimage_start);
96 	puts("\n");
97 
98 	/* This area are prepared for mallocing when decompressing */
99 	free_mem_ptr = boot_heap_start;
100 	free_mem_end_ptr = boot_heap_start + BOOT_HEAP_SIZE;
101 
102 	/* Display standard Linux/MIPS boot prompt */
103 	puts("Uncompressing Linux at load address ");
104 	puthex(VMLINUX_LOAD_ADDRESS_ULL);
105 	puts("\n");
106 
107 	/* Decompress the kernel with according algorithm */
108 	decompress((char *)zimage_start, zimage_size, 0, 0,
109 		   (void *)VMLINUX_LOAD_ADDRESS_ULL, 0, error);
110 
111 	/* FIXME: should we flush cache here? */
112 	puts("Now, booting the kernel...\n");
113 }
114