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 void *memcpy(void *dest, const void *src, size_t n)
48 {
49 	int i;
50 	const char *s = src;
51 	char *d = dest;
52 
53 	for (i = 0; i < n; i++)
54 		d[i] = s[i];
55 	return dest;
56 }
57 #include "../../../../lib/decompress_inflate.c"
58 #endif
59 
60 #ifdef CONFIG_KERNEL_BZIP2
61 void *memset(void *s, int c, size_t n)
62 {
63 	int i;
64 	char *ss = s;
65 
66 	for (i = 0; i < n; i++)
67 		ss[i] = c;
68 	return s;
69 }
70 #include "../../../../lib/decompress_bunzip2.c"
71 #endif
72 
73 #ifdef CONFIG_KERNEL_LZMA
74 #include "../../../../lib/decompress_unlzma.c"
75 #endif
76 
77 #ifdef CONFIG_KERNEL_LZO
78 #include "../../../../lib/decompress_unlzo.c"
79 #endif
80 
81 void decompress_kernel(unsigned long boot_heap_start)
82 {
83 	unsigned long zimage_start, zimage_size;
84 
85 	zimage_start = (unsigned long)(&__image_begin);
86 	zimage_size = (unsigned long)(&__image_end) -
87 	    (unsigned long)(&__image_begin);
88 
89 	puts("zimage at:     ");
90 	puthex(zimage_start);
91 	puts(" ");
92 	puthex(zimage_size + zimage_start);
93 	puts("\n");
94 
95 	/* This area are prepared for mallocing when decompressing */
96 	free_mem_ptr = boot_heap_start;
97 	free_mem_end_ptr = boot_heap_start + BOOT_HEAP_SIZE;
98 
99 	/* Display standard Linux/MIPS boot prompt */
100 	puts("Uncompressing Linux at load address ");
101 	puthex(VMLINUX_LOAD_ADDRESS_ULL);
102 	puts("\n");
103 
104 	/* Decompress the kernel with according algorithm */
105 	decompress((char *)zimage_start, zimage_size, 0, 0,
106 		   (void *)VMLINUX_LOAD_ADDRESS_ULL, 0, error);
107 
108 	/* FIXME: should we flush cache here? */
109 	puts("Now, booting the kernel...\n");
110 }
111