target/linux/mediatek/image/gen_mtk_mmc_img.sh

   1 #!/bin/sh
   2 #
   3 # Copyright © 2019 Alexey Loukianov <lx2@lexa2.ru>
   4 # Copyright © 2020 David Woodhouse <dwmw2@infradead.org>
   5 #
   6 # This is free software, licensed under the GNU General Public License v2.
   7 # See /LICENSE for more information.
   8 #
   9
  10 # Generates a bootable SD card image for Banana Pi R2 (and probably
  11 # other similar boards) as documented at
  12 # http://www.fw-web.de/dokuwiki/doku.php?id=en:bpi-r2:storage
  13 #
  14 # The first sector must contain the SDMMC_BOOT header shown
  15 # below, and also contains the MBR partition table in the end
  16 # of the sector. The partition table must contain no active
  17 # partitions.
  18 #
  19 # The second sector must contain the BRLYT header, and the
  20 # special preloader image goes in sector 4; 2KiB into the image.
  21 #
  22 # The preloader loads U-Boot from  sector 640; 320KiB into the image.
  23 # The location and the size (512KiB) are fixed and not read from
  24 # the partition table. We set up a partition for it merely for
  25 # our own convenience for upgrades, etc.
  26 #
  27 # The second partition is a FAT file system containing the kernel
  28 # image and a uboot.env file, which is provided to this script as
  29 # $4 (bootfs image). Its size is configurable with the
  30 # CONFIG_MTK_BOOT_PARTSIZE option; by default 32MiB.
  31 #
  32 # The root filesystem comes next in the third partition.
  33 #
  34 #
  35 #   ------------------------   Sector   Offset
  36 #   |  MBR + SDMMC_BOOT    |     0       0x0
  37 #   |----------------------|
  38 #   |     BRLYT header     |     1       0x200
  39 #   |----------------------|
  40 #   .                      .
  41 #   .                      .
  42 #   |----------------------|
  43 #   |                      |     4       0x800
  44 #   |                      |
  45 #   |     Preloader        |
  46 #   .                      .
  47 #   .                      .
  48 #   |                      |     639
  49 #   |----------------------|
  50 #   |   MBR partition #1   |     640     0x50000
  51 #   |                      |
  52 #   |       U-Boot         |
  53 #   .                      .
  54 #   .                      .
  55 #   |                      |     1663
  56 #   |----------------------|
  57 #   |   MBR partition #2   |
  58 #   |                      |
  59 #   |    FAT partition     |   ( MTK_BOOT_PARTSIZE
  60 #   .                      .     default 32MiB )
  61 #   .    (kernel, uEnv)    .
  62 #   |                      |
  63 #   |----------------------|
  64 #   |   MBR partition #3   |
  65 #   |                      |
  66 #   |   Root partition     |
  67 #   |                      |   ( TARGET_ROOTFS_PARTSIZE
  68 #   |  (squashfs+overlay   |     default 104MiB )
  69 #   .    or ext4, etc.)    .
  70 #   .                      .
  71 #   |                      |
  72 #   ------------------------
  73 #
  74 # For eMMC boot, everything up to and including the preloader must be
  75 # written to /dev/mmcblk0boot0, with the SDMMC_BOOT header changed to
  76 # read EMMC_BOOT\0 instead.
  77 #
  78 # The contents of the main eMMC are identical to the SD card layout,
  79 # with the preloader loading 512KiB of U-Boot starting at 0x50000.
  80
  81 usage() {
  82     echo "SYNTAX: $0 sd <file> <preloader image> <u-boot image> <u-boot offset> <bootfs image> <rootfs image> <bootfs size> <rootfs size>"
  83     echo " OR:    $0 emmc <file> <preloader image>"
  84     exit 1
  85 }
  86
  87 set -e
  88
  89 PRELOADER_OFFSET=2     # 2KiB
  90
  91 SDMMC_BOOT="SDMMC_BOOT\x00\x00\x01\x00\x00\x00\x00\x02\x00\x00"
  92 EMMC_BOOT="EMMC_BOOT\x00\x00\x00\x01\x00\x00\x00\x00\x02\x00\x00"
  93 BRLYT="BRLYT\x00\x00\x00\x01\x00\x00\x00\x00\x08\x00\x00\
  94 \x00\x08\x00\x00\x42\x42\x42\x42\x08\x00\x01\x00\x00\x08\x00\x00\
  95 \x00\x08\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
  96
  97 case $1 in
  98  sd)
  99         [ $# -eq 9 ] || usage
 100         OUTPUT="$2"
 101         PRELOADER="$3"
 102         UBOOT="$4"
 103         UBOOTOFS="$5"
 104         BOOTFS="$6"
 105         ROOTFS="$7"
 106         BOOTFSSIZE="$8"
 107         ROOTFSSIZE="$9"
 108
 109         head=4
 110         sect=63
 111
 112         set $(ptgen -o $OUTPUT -h $head -s $sect -a 0 -l 1024 \
 113                     -t 41 -p 512k@${UBOOTOFS} \
 114                     -t c -p ${BOOTFSSIZE}M \
 115                     -t 83 -p ${ROOTFSSIZE}M )
 116
 117         UBOOT_OFFSET="$(($1 / 512))"
 118         UBOOT_SIZE="$(($2 / 512))"
 119         BOOTFS_OFFSET="$(($3 / 512))"
 120         BOOTFS_SIZE="$(($4 / 512))"
 121         ROOTFS_OFFSET="$(($5 / 512))"
 122         ROOTFS_SIZE="$(($6 / 512))"
 123
 124         echo -en "${SDMMC_BOOT}" | dd bs=1 of="${OUTPUT}" seek=0   conv=notrunc
 125         echo -en "${BRLYT}"      | dd bs=1 of="${OUTPUT}" seek=512 conv=notrunc
 126
 127         # For eMMC-only boards like U7623 the preloader doesn't need to be included in the
 128         # main image as it's only ever needed in the eMMC boot partition.
 129         if [ -r ${PRELOADER} ]; then
 130             dd bs=1024 if="${PRELOADER}" of="${OUTPUT}" seek="${PRELOADER_OFFSET}" conv=notrunc
 131         fi
 132         dd bs=512  if="${UBOOT}"     of="${OUTPUT}" seek="${UBOOT_OFFSET}"     conv=notrunc
 133         dd bs=512  if="${BOOTFS}"    of="${OUTPUT}" seek="${BOOTFS_OFFSET}"    conv=notrunc
 134         dd bs=512  if="${ROOTFS}"    of="${OUTPUT}" seek="${ROOTFS_OFFSET}"    conv=notrunc
 135         dd bs=128k if=/dev/zero      of="${OUTPUT}" count=1    oflag=append    conv=notrunc
 136         ;;
 137  emmc)
 138         [ $# -eq 3 ] || usage
 139         OUTPUT="$2"
 140         PRELOADER="$3"
 141
 142         echo -en "${EMMC_BOOT}"  | dd bs=1 of="${OUTPUT}" seek=0
 143         echo -en "${BRLYT}"      | dd bs=1 of="${OUTPUT}" seek=512 conv=notrunc
 144
 145         dd bs=1024 if="${PRELOADER}" of="${OUTPUT}" seek="${PRELOADER_OFFSET}" conv=notrunc
 146         ;;
 147  *)
 148         usage
 149         ;;
 150 esac