xref: /linux/arch/mips/boot/compressed/decompress.c (revision 7ec462100ef9142344ddbf86f2c3008b97acddbe)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright 2001 MontaVista Software Inc.
4  * Author: Matt Porter <mporter@mvista.com>
5  *
6  * Copyright (C) 2009 Lemote, Inc.
7  * Author: Wu Zhangjin <wuzhangjin@gmail.com>
8  */
9 
10 #define DISABLE_BRANCH_PROFILING
11 
12 #define __NO_FORTIFY
13 #include <linux/types.h>
14 #include <linux/kernel.h>
15 #include <linux/string.h>
16 #include <linux/libfdt.h>
17 
18 #include <asm/addrspace.h>
19 #include <linux/unaligned.h>
20 #include <asm-generic/vmlinux.lds.h>
21 
22 #include "decompress.h"
23 
24 /*
25  * These two variables specify the free mem region
26  * that can be used for temporary malloc area
27  */
28 unsigned long free_mem_ptr;
29 unsigned long free_mem_end_ptr;
30 
error(char * x)31 void error(char *x)
32 {
33 	puts("\n\n");
34 	puts(x);
35 	puts("\n\n -- System halted");
36 
37 	while (1)
38 		;	/* Halt */
39 }
40 
41 /* activate the code for pre-boot environment */
42 #define STATIC static
43 
44 #ifdef CONFIG_KERNEL_GZIP
45 #include "../../../../lib/decompress_inflate.c"
46 #endif
47 
48 #ifdef CONFIG_KERNEL_BZIP2
49 #include "../../../../lib/decompress_bunzip2.c"
50 #endif
51 
52 #ifdef CONFIG_KERNEL_LZ4
53 #include "../../../../lib/decompress_unlz4.c"
54 #endif
55 
56 #ifdef CONFIG_KERNEL_LZMA
57 #include "../../../../lib/decompress_unlzma.c"
58 #endif
59 
60 #ifdef CONFIG_KERNEL_LZO
61 #include "../../../../lib/decompress_unlzo.c"
62 #endif
63 
64 #ifdef CONFIG_KERNEL_XZ
65 #include "../../../../lib/decompress_unxz.c"
66 #endif
67 
68 #ifdef CONFIG_KERNEL_ZSTD
69 #include "../../../../lib/decompress_unzstd.c"
70 #endif
71 
72 const unsigned long __stack_chk_guard = 0x000a0dff;
73 
__stack_chk_fail(void)74 void __stack_chk_fail(void)
75 {
76 	error("stack-protector: Kernel stack is corrupted\n");
77 }
78 
decompress_kernel(unsigned long boot_heap_start)79 void decompress_kernel(unsigned long boot_heap_start)
80 {
81 	unsigned long zimage_start, zimage_size;
82 
83 	zimage_start = (unsigned long)(__image_begin);
84 	zimage_size = (unsigned long)(__image_end) -
85 	    (unsigned long)(__image_begin);
86 
87 	puts("zimage at:     ");
88 	puthex(zimage_start);
89 	puts(" ");
90 	puthex(zimage_size + zimage_start);
91 	puts("\n");
92 
93 	/* This area are prepared for mallocing when decompressing */
94 	free_mem_ptr = boot_heap_start;
95 	free_mem_end_ptr = boot_heap_start + BOOT_HEAP_SIZE;
96 
97 	/* Display standard Linux/MIPS boot prompt */
98 	puts("Uncompressing Linux at load address ");
99 	puthex(VMLINUX_LOAD_ADDRESS_ULL);
100 	puts("\n");
101 
102 	/* Decompress the kernel with according algorithm */
103 	__decompress((char *)zimage_start, zimage_size, 0, 0,
104 		   (void *)VMLINUX_LOAD_ADDRESS_ULL, 0, 0, error);
105 
106 	if (IS_ENABLED(CONFIG_MIPS_RAW_APPENDED_DTB) &&
107 	    fdt_magic((void *)&__appended_dtb) == FDT_MAGIC) {
108 		unsigned int image_size, dtb_size;
109 
110 		dtb_size = fdt_totalsize((void *)&__appended_dtb);
111 
112 		/* last four bytes is always image size in little endian */
113 		image_size = get_unaligned_le32((void *)__image_end - 4);
114 
115 		/* The device tree's address must be properly aligned  */
116 		image_size = ALIGN(image_size, STRUCT_ALIGNMENT);
117 
118 		puts("Copy device tree to address  ");
119 		puthex(VMLINUX_LOAD_ADDRESS_ULL + image_size);
120 		puts("\n");
121 
122 		/* copy dtb to where the booted kernel will expect it */
123 		memcpy((void *)VMLINUX_LOAD_ADDRESS_ULL + image_size,
124 		       __appended_dtb, dtb_size);
125 	}
126 
127 	/* FIXME: should we flush cache here? */
128 	puts("Now, booting the kernel...\n");
129 }
130