arch/mips/boot/compressed/decompress.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright 2001 MontaVista Software Inc.
   4  * Author: Matt Porter <[email protected]>
   5  *
   6  * Copyright (C) 2009 Lemote, Inc.
   7  * Author: Wu Zhangjin <[email protected]>
   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 <asm/unaligned.h>
  20 #include <asm-generic/vmlinux.lds.h>
  21
  22 /*
  23  * These two variables specify the free mem region
  24  * that can be used for temporary malloc area
  25  */
  26 unsigned long free_mem_ptr;
  27 unsigned long free_mem_end_ptr;
  28
  29 /* The linker tells us where the image is. */
  30 extern unsigned char __image_begin[], __image_end[];
  31
  32 /* debug interfaces  */
  33 #ifdef CONFIG_DEBUG_ZBOOT
  34 extern void puts(const char *s);
  35 extern void puthex(unsigned long long val);
  36 #else
  37 #define puts(s) do {} while (0)
  38 #define puthex(val) do {} while (0)
  39 #endif
  40
  41 extern char __appended_dtb[];
  42
  43 void error(char *x)
  44 {
  45         puts("\n\n");
  46         puts(x);
  47         puts("\n\n -- System halted");
  48
  49         while (1)
  50                 ;       /* Halt */
  51 }
  52
  53 /* activate the code for pre-boot environment */
  54 #define STATIC static
  55
  56 #ifdef CONFIG_KERNEL_GZIP
  57 #include "../../../../lib/decompress_inflate.c"
  58 #endif
  59
  60 #ifdef CONFIG_KERNEL_BZIP2
  61 #include "../../../../lib/decompress_bunzip2.c"
  62 #endif
  63
  64 #ifdef CONFIG_KERNEL_LZ4
  65 #include "../../../../lib/decompress_unlz4.c"
  66 #endif
  67
  68 #ifdef CONFIG_KERNEL_LZMA
  69 #include "../../../../lib/decompress_unlzma.c"
  70 #endif
  71
  72 #ifdef CONFIG_KERNEL_LZO
  73 #include "../../../../lib/decompress_unlzo.c"
  74 #endif
  75
  76 #ifdef CONFIG_KERNEL_XZ
  77 #include "../../../../lib/decompress_unxz.c"
  78 #endif
  79
  80 #ifdef CONFIG_KERNEL_ZSTD
  81 #include "../../../../lib/decompress_unzstd.c"
  82 #endif
  83
  84 const unsigned long __stack_chk_guard = 0x000a0dff;
  85
  86 void __stack_chk_fail(void)
  87 {
  88         error("stack-protector: Kernel stack is corrupted\n");
  89 }
  90
  91 void decompress_kernel(unsigned long boot_heap_start)
  92 {
  93         unsigned long zimage_start, zimage_size;
  94
  95         zimage_start = (unsigned long)(__image_begin);
  96         zimage_size = (unsigned long)(__image_end) -
  97             (unsigned long)(__image_begin);
  98
  99         puts("zimage at:     ");
 100         puthex(zimage_start);
 101         puts(" ");
 102         puthex(zimage_size + zimage_start);
 103         puts("\n");
 104
 105         /* This area are prepared for mallocing when decompressing */
 106         free_mem_ptr = boot_heap_start;
 107         free_mem_end_ptr = boot_heap_start + BOOT_HEAP_SIZE;
 108
 109         /* Display standard Linux/MIPS boot prompt */
 110         puts("Uncompressing Linux at load address ");
 111         puthex(VMLINUX_LOAD_ADDRESS_ULL);
 112         puts("\n");
 113
 114         /* Decompress the kernel with according algorithm */
 115         __decompress((char *)zimage_start, zimage_size, 0, 0,
 116                    (void *)VMLINUX_LOAD_ADDRESS_ULL, 0, 0, error);
 117
 118         if (IS_ENABLED(CONFIG_MIPS_RAW_APPENDED_DTB) &&
 119             fdt_magic((void *)&__appended_dtb) == FDT_MAGIC) {
 120                 unsigned int image_size, dtb_size;
 121
 122                 dtb_size = fdt_totalsize((void *)&__appended_dtb);
 123
 124                 /* last four bytes is always image size in little endian */
 125                 image_size = get_unaligned_le32((void *)__image_end - 4);
 126
 127                 /* The device tree's address must be properly aligned  */
 128                 image_size = ALIGN(image_size, STRUCT_ALIGNMENT);
 129
 130                 puts("Copy device tree to address  ");
 131                 puthex(VMLINUX_LOAD_ADDRESS_ULL + image_size);
 132                 puts("\n");
 133
 134                 /* copy dtb to where the booted kernel will expect it */
 135                 memcpy((void *)VMLINUX_LOAD_ADDRESS_ULL + image_size,
 136                        __appended_dtb, dtb_size);
 137         }
 138
 139         /* FIXME: should we flush cache here? */
 140         puts("Now, booting the kernel...\n");
 141 }