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 <mporter@mvista.com>
   5  *
   6  * Copyright (C) 2009 Lemote, Inc.
   7  * Author: Wu Zhangjin <wuzhangjin@gmail.com>
   8  */
   9
  10 #include <linux/types.h>
  11 #include <linux/kernel.h>
  12 #include <linux/string.h>
  13 #include <linux/libfdt.h>
  14
  15 #include <asm/addrspace.h>
  16
  17 /*
  18  * These two variables specify the free mem region
  19  * that can be used for temporary malloc area
  20  */
  21 unsigned long free_mem_ptr;
  22 unsigned long free_mem_end_ptr;
  23
  24 /* The linker tells us where the image is. */
  25 extern unsigned char __image_begin, __image_end;
  26
  27 /* debug interfaces  */
  28 #ifdef CONFIG_DEBUG_ZBOOT
  29 extern void puts(const char *s);
  30 extern void puthex(unsigned long long val);
  31 #else
  32 #define puts(s) do {} while (0)
  33 #define puthex(val) do {} while (0)
  34 #endif
  35
  36 extern char __appended_dtb[];
  37
  38 void error(char *x)
  39 {
  40         puts("\n\n");
  41         puts(x);
  42         puts("\n\n -- System halted");
  43
  44         while (1)
  45                 ;       /* Halt */
  46 }
  47
  48 /* activate the code for pre-boot environment */
  49 #define STATIC static
  50
  51 #ifdef CONFIG_KERNEL_GZIP
  52 #include "../../../../lib/decompress_inflate.c"
  53 #endif
  54
  55 #ifdef CONFIG_KERNEL_BZIP2
  56 #include "../../../../lib/decompress_bunzip2.c"
  57 #endif
  58
  59 #ifdef CONFIG_KERNEL_LZ4
  60 #include "../../../../lib/decompress_unlz4.c"
  61 #endif
  62
  63 #ifdef CONFIG_KERNEL_LZMA
  64 #include "../../../../lib/decompress_unlzma.c"
  65 #endif
  66
  67 #ifdef CONFIG_KERNEL_LZO
  68 #include "../../../../lib/decompress_unlzo.c"
  69 #endif
  70
  71 #ifdef CONFIG_KERNEL_XZ
  72 #include "../../../../lib/decompress_unxz.c"
  73 #endif
  74
  75 #ifdef CONFIG_KERNEL_ZSTD
  76 #include "../../../../lib/decompress_unzstd.c"
  77 #endif
  78
  79 const unsigned long __stack_chk_guard = 0x000a0dff;
  80
  81 void __stack_chk_fail(void)
  82 {
  83         error("stack-protector: Kernel stack is corrupted\n");
  84 }
  85
  86 void decompress_kernel(unsigned long boot_heap_start)
  87 {
  88         unsigned long zimage_start, zimage_size;
  89
  90         zimage_start = (unsigned long)(&__image_begin);
  91         zimage_size = (unsigned long)(&__image_end) -
  92             (unsigned long)(&__image_begin);
  93
  94         puts("zimage at:     ");
  95         puthex(zimage_start);
  96         puts(" ");
  97         puthex(zimage_size + zimage_start);
  98         puts("\n");
  99
 100         /* This area are prepared for mallocing when decompressing */
 101         free_mem_ptr = boot_heap_start;
 102         free_mem_end_ptr = boot_heap_start + BOOT_HEAP_SIZE;
 103
 104         /* Display standard Linux/MIPS boot prompt */
 105         puts("Uncompressing Linux at load address ");
 106         puthex(VMLINUX_LOAD_ADDRESS_ULL);
 107         puts("\n");
 108
 109         /* Decompress the kernel with according algorithm */
 110         __decompress((char *)zimage_start, zimage_size, 0, 0,
 111                    (void *)VMLINUX_LOAD_ADDRESS_ULL, 0, 0, error);
 112
 113         if (IS_ENABLED(CONFIG_MIPS_RAW_APPENDED_DTB) &&
 114             fdt_magic((void *)&__appended_dtb) == FDT_MAGIC) {
 115                 unsigned int image_size, dtb_size;
 116
 117                 dtb_size = fdt_totalsize((void *)&__appended_dtb);
 118
 119                 /* last four bytes is always image size in little endian */
 120                 image_size = le32_to_cpup((void *)&__image_end - 4);
 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 }