util/cbfstool/linux.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 /*
   4  * Linux/i386 loader
   5  * Supports bzImage, zImage and Image format.
   6  *
   7  * Based on work by Steve Gehlbach.
   8  * Portions are taken from mkelfImage.
   9  *
  10  * 2003-09 by SONE Takeshi
  11  */
  12
  13 #include <stdint.h>
  14 #include "linux_trampoline.h"
  15
  16 typedef uint8_t u8;
  17 typedef uint16_t u16;
  18 typedef uint32_t u32;
  19 typedef uint64_t u64;
  20
  21 #define E820MAX 32              /* number of entries in E820MAP */
  22 struct e820entry {
  23         u64 addr;               /* start of memory segment */
  24         u64 size;               /* size of memory segment */
  25         u32 type;               /* type of memory segment */
  26 #define E820_RAM        1
  27 #define E820_RESERVED   2
  28 #define E820_ACPI       3       /* usable as RAM once ACPI tables have been read */
  29 #define E820_NVS        4
  30 } __packed;
  31
  32 /* The header of Linux/i386 kernel */
  33 struct linux_header {
  34         u8 reserved1[0x1f1];    /* 0x000 */
  35         u8 setup_sects;         /* 0x1f1 */
  36         u16 root_flags;         /* 0x1f2 */
  37         u32 syssize;            /* 0x1f4 (2.04+) */
  38         u8 reserved2[2];        /* 0x1f8 */
  39         u16 vid_mode;           /* 0x1fa */
  40         u16 root_dev;           /* 0x1fc */
  41         u16 boot_sector_magic;  /* 0x1fe */
  42         /* 2.00+ */
  43         u8 reserved3[2];        /* 0x200 */
  44         u8 header_magic[4];     /* 0x202 */
  45         u16 protocol_version;   /* 0x206 */
  46         u32 realmode_swtch;     /* 0x208 */
  47         u16 start_sys;          /* 0x20c */
  48         u16 kver_addr;          /* 0x20e */
  49         u8 type_of_loader;      /* 0x210 */
  50         u8 loadflags;           /* 0x211 */
  51         u16 setup_move_size;    /* 0x212 */
  52         u32 code32_start;       /* 0x214 */
  53         u32 ramdisk_image;      /* 0x218 */
  54         u32 ramdisk_size;       /* 0x21c */
  55         u8 reserved4[4];        /* 0x220 */
  56         /* 2.01+ */
  57         u16 heap_end_ptr;       /* 0x224 */
  58         u8 reserved5[2];        /* 0x226 */
  59         /* 2.02+ */
  60         u32 cmd_line_ptr;       /* 0x228 */
  61         /* 2.03+ */
  62         u32 initrd_addr_max;    /* 0x22c */
  63         /* 2.05+ */
  64         u32 kernel_alignment;   /* 0x230 */
  65         u8 relocatable_kernel;  /* 0x234 */
  66         u8 min_alignment;       /* 0x235 (2.10+) */
  67         u8 reserved6[2];        /* 0x236 */
  68         /* 2.06+ */
  69         u32 cmdline_size;       /* 0x238 */
  70         /* 2.07+ */
  71         u32 hardware_subarch;   /* 0x23c */
  72         u64 hardware_subarch_data;/* 0x240 */
  73         /* 2.08+ */
  74         u32 payload_offset;     /* 0x248 */
  75         u32 payload_length;     /* 0x24c */
  76         /* 2.09+ */
  77         u64 setup_data;         /* 0x250 */
  78         /* 2.10+ */
  79         u64 pref_address;       /* 0x258 */
  80         u32 init_size;          /* 0x260 */
  81 } __packed;
  82
  83 /* Parameters passed to 32-bit part of Linux
  84  * This is another view of the structure above.. */
  85 struct linux_params {
  86         u8 orig_x;              /* 0x00 */
  87         u8 orig_y;              /* 0x01 */
  88         u16 ext_mem_k;          /* 0x02 -- EXT_MEM_K sits here */
  89         u16 orig_video_page;    /* 0x04 */
  90         u8 orig_video_mode;     /* 0x06 */
  91         u8 orig_video_cols;     /* 0x07 */
  92         u16 unused2;            /* 0x08 */
  93         u16 orig_video_ega_bx;  /* 0x0a */
  94         u16 unused3;            /* 0x0c */
  95         u8 orig_video_lines;    /* 0x0e */
  96         u8 orig_video_isVGA;    /* 0x0f */
  97         u16 orig_video_points;  /* 0x10 */
  98
  99         /* VESA graphic mode -- linear frame buffer */
 100         u16 lfb_width;          /* 0x12 */
 101         u16 lfb_height;         /* 0x14 */
 102         u16 lfb_depth;          /* 0x16 */
 103         u32 lfb_base;           /* 0x18 */
 104         u32 lfb_size;           /* 0x1c */
 105         u16 cl_magic;           /* 0x20 */
 106 #define CL_MAGIC_VALUE 0xA33F
 107         u16 cl_offset;          /* 0x22 */
 108         u16 lfb_linelength;     /* 0x24 */
 109         u8 red_size;            /* 0x26 */
 110         u8 red_pos;             /* 0x27 */
 111         u8 green_size;          /* 0x28 */
 112         u8 green_pos;           /* 0x29 */
 113         u8 blue_size;           /* 0x2a */
 114         u8 blue_pos;            /* 0x2b */
 115         u8 rsvd_size;           /* 0x2c */
 116         u8 rsvd_pos;            /* 0x2d */
 117         u16 vesapm_seg;         /* 0x2e */
 118         u16 vesapm_off;         /* 0x30 */
 119         u16 pages;              /* 0x32 */
 120         u8 reserved4[12];       /* 0x34 -- 0x3f reserved for future expansion */
 121
 122         //struct apm_bios_info apm_bios_info;   /* 0x40 */
 123         u8 apm_bios_info[0x40];
 124         //struct drive_info_struct drive_info;  /* 0x80 */
 125         u8 drive_info[0x20];
 126         //struct sys_desc_table sys_desc_table; /* 0xa0 */
 127         u8 sys_desc_table[0x140];
 128         u32 alt_mem_k;          /* 0x1e0 */
 129         u8 reserved5[4];        /* 0x1e4 */
 130         u8 e820_map_nr;         /* 0x1e8 */
 131         u8 reserved6[8];        /* 0x1e9 */
 132                                 /* This next variable is to show where
 133                                  * in this struct the Linux setup_hdr
 134                                  * is located. It does not get filled in.
 135                                  * We may someday find it useful to use
 136                                  * its address. */
 137         u8 setup_hdr;           /* 0x1f1  */
 138         u16 mount_root_rdonly;  /* 0x1f2 */
 139         u8 reserved7[4];        /* 0x1f4 */
 140         u16 ramdisk_flags;      /* 0x1f8 */
 141 #define RAMDISK_IMAGE_START_MASK        0x07FF
 142 #define RAMDISK_PROMPT_FLAG             0x8000
 143 #define RAMDISK_LOAD_FLAG               0x4000
 144         u8 reserved8[2];        /* 0x1fa */
 145         u16 orig_root_dev;      /* 0x1fc */
 146         u8 reserved9[1];        /* 0x1fe */
 147         u8 aux_device_info;     /* 0x1ff */
 148         u8 reserved10[2];       /* 0x200 */
 149         u8 param_block_signature[4];    /* 0x202 */
 150         u16 param_block_version;        /* 0x206 */
 151         u8 reserved11[8];       /* 0x208 */
 152         u8 loader_type;         /* 0x210 */
 153 #define LOADER_TYPE_LOADLIN         1
 154 #define LOADER_TYPE_BOOTSECT_LOADER 2
 155 #define LOADER_TYPE_SYSLINUX        3
 156 #define LOADER_TYPE_ETHERBOOT       4
 157 #define LOADER_TYPE_KERNEL          5
 158         u8 loader_flags;        /* 0x211 */
 159         u8 reserved12[2];       /* 0x212 */
 160         u32 kernel_start;       /* 0x214 */
 161         u32 initrd_start;       /* 0x218 */
 162         u32 initrd_size;        /* 0x21c */
 163         u8 reserved12_5[8];     /* 0x220 */
 164         u32 cmd_line_ptr;       /* 0x228 */
 165         u32 initrd_addr_max;    /* 0x22c */
 166         u32 kernel_alignment;   /* 0x230 */
 167         u8 relocatable_kernel;  /* 0x234 */
 168         u8 reserved13[0x2b];            /* 0x235 */
 169         u32 init_size;          /* 0x260 */
 170         u8 reserved14[0x6c];            /* 0x264 */
 171         struct e820entry e820_map[E820MAX];     /* 0x2d0 */
 172         u8 reserved16[688];     /* 0x550 */
 173 #define COMMAND_LINE_SIZE 256
 174         /* Command line is copied here by 32-bit i386/kernel/head.S.
 175          * So I will follow the boot protocol, rather than putting it
 176          * directly here. --ts1 */
 177         u8 command_line[COMMAND_LINE_SIZE];     /* 0x800 */
 178         u8 reserved17[1792];    /* 0x900 - 0x1000 */
 179 };