target/linux/ath79/generic/base-files/lib/upgrade/openmesh.sh

   1 # The U-Boot loader of the OpenMesh devices requires image sizes and
   2 # checksums to be provided in the U-Boot environment.
   3 # The OpenMesh devices come with 2 main partitions - while one is active
   4 # sysupgrade will flash the other. The boot order is changed to boot the
   5 # newly flashed partition. If the new partition can't be booted due to
   6 # upgrade failures the previously used partition is loaded.
   7
   8 cfg_value_get()
   9 {
  10         local cfg=$1 cfg_opt
  11         local section=$2 our_section=0
  12         local param=$3 our_param=
  13
  14         for cfg_opt in $cfg; do
  15                 [ "$cfg_opt" = "[$section]" ] && our_section=1 && continue
  16                 [ "$our_section" = "1" ] || continue
  17
  18                 our_param=${cfg_opt%%=*}
  19                 [ "$param" = "$our_param" ] && echo ${cfg_opt##*=} && break
  20         done
  21 }
  22
  23 platform_do_upgrade_openmesh()
  24 {
  25         local img_path="$1"
  26         local restore_backup
  27
  28         local setenv_script="/tmp/fw_env_upgrade"
  29
  30         local inactive_mtd="$(find_mtd_index $PART_NAME)"
  31         local inactive_offset="$(cat /sys/class/mtd/mtd${inactive_mtd}/offset)"
  32         local total_size="$(cat /sys/class/mtd/mtd${inactive_mtd}/size)"
  33         local flash_start_mem=0x9f000000
  34         local data_offset=$((64 * 1024))
  35
  36         # detect to which flash region the new image is written to.
  37         #
  38         # 1. check what is the mtd index for the first flash region on this
  39         #    device
  40         # 2. check if the target partition ("inactive") has the mtd index of
  41         #    the first flash region
  42         #
  43         #    - when it is: the new bootseq will be 1,2 and the first region is
  44         #      modified
  45         #    - when it isn't: bootseq will be 2,1 and the second region is
  46         #      modified
  47         #
  48         # The detection has to be done via the hardcoded mtd partition because
  49         # the current boot might be done with the fallback region. Let us
  50         # assume that the current bootseq is 1,2. The bootloader detected that
  51         # the image in flash region 1 is corrupt and thus switches to flash
  52         # region 2. The bootseq in the u-boot-env is now still the same and
  53         # the sysupgrade code can now only rely on the actual mtd indexes and
  54         # not the bootseq variable to detect the currently booted flash
  55         # region/image.
  56         #
  57         # In the above example, an implementation which uses bootseq ("1,2") to
  58         # detect the currently booted image would assume that region 1 is booted
  59         # and then overwrite the variables for the wrong flash region (aka the
  60         # one which isn't modified). This could result in a device which doesn't
  61         # boot anymore to Linux until it was reflashed with ap51-flash.
  62         local next_boot_part="1"
  63         local primary_kernel_mtd="3"
  64         [ "$inactive_mtd" = "$primary_kernel_mtd" ] || next_boot_part="2"
  65
  66         local cfg_size=$(dd if="$img_path" bs=2 skip=35 count=4 2>/dev/null)
  67         local cfg_length=$((0x$cfg_size))
  68         local cfg_content=$(dd if="$img_path" bs=1 skip=$data_offset count=$cfg_length 2>/dev/null)
  69
  70         local kernel_size=$(dd if="$img_path" bs=2 skip=71 count=4 2>/dev/null)
  71         local kernel_length=$((0x$kernel_size))
  72         local kernel_md5=$(cfg_value_get "$cfg_content" "vmlinux" "md5sum")
  73
  74         local rootfs_size=$(dd if="$img_path" bs=2 skip=107 count=4 2>/dev/null)
  75         local rootfs_length=$((0x$rootfs_size))
  76         local rootfs_md5=$(cfg_value_get "$cfg_content" "rootfs" "md5sum")
  77         local rootfs_checksize=$(cfg_value_get "$cfg_content" "rootfs" "checksize")
  78
  79         # take care of restoring a saved config
  80         [ -n "$UPGRADE_BACKUP" ] && restore_backup="${MTD_CONFIG_ARGS} -j ${UPGRADE_BACKUP}"
  81
  82         # write image parts
  83         mtd -q erase inactive
  84         dd if="$img_path" bs=1 skip=$((data_offset + cfg_length + kernel_length)) count=$rootfs_length 2>&- | \
  85                 mtd -n -p $kernel_length $restore_backup write - $PART_NAME
  86         dd if="$img_path" bs=1 skip=$((data_offset + cfg_length)) count=$kernel_length 2>&- | \
  87                 mtd -n write - $PART_NAME
  88
  89         # prepare new u-boot env
  90         if [ "$next_boot_part" = "1" ]; then
  91                 echo "bootseq 1,2" > $setenv_script
  92         else
  93                 echo "bootseq 2,1" > $setenv_script
  94         fi
  95
  96         printf "kernel_size_%i %i\n" $next_boot_part $((kernel_length / 1024)) >> $setenv_script
  97         printf "vmlinux_start_addr 0x%08x\n" $((flash_start_mem + inactive_offset)) >> $setenv_script
  98         printf "vmlinux_size 0x%08x\n" ${kernel_length} >> $setenv_script
  99         printf "vmlinux_checksum %s\n" ${kernel_md5} >> $setenv_script
 100
 101         printf "rootfs_size_%i %i\n" $next_boot_part $(((total_size-kernel_length) / 1024)) >> $setenv_script
 102         printf "rootfs_start_addr 0x%08x\n" $((flash_start_mem+inactive_offset+kernel_length)) >> $setenv_script
 103         printf "rootfs_size %s\n" $rootfs_checksize >> $setenv_script
 104         printf "rootfs_checksum %s\n" ${rootfs_md5} >> $setenv_script
 105
 106         # store u-boot env changes
 107         mkdir -p /var/lock
 108         fw_setenv -s $setenv_script || {
 109                 echo "failed to update U-Boot environment"
 110                 return 1
 111         }
 112 }