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 <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
  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
  74 void __stack_chk_fail(void)
  75 {
  76         error("stack-protector: Kernel stack is corrupted\n");
  77 }
  78
  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 }