Miscellaneous Projects » SuperSignal AP 2820V

h1. Table

partitions seen during boot:

<pre>

  0: 0001F800      1        0 "bootdata"

  1: 0001F800      1        0 "unitdata"

  2: 004AD000     38       37 "linux-A"

  3: 004AD000     38       37 "linux-B"

  4: 007E0000     64       63 "linux-R"

  5: 00B32800     91       90 "rfs-A"

  6: 00B32800     91       90 "rfs-B"

  7: 00372000     28       27 "app-A"

  8: 00372000     28       27 "app-B"

  9: 00A17000     65       81 "data-A"

 10: 00685800     29       52 "data-B"

 11: 0001F800      1        0 "bootdata_backup"

 12: 0001F800      1        0 "caldata"

 13: 0001F800      1        0 "caldata_backup"

 14: 0001F800      1        0 "unitdata_backup"

</pre>

partitions mapped after boot (using @cat /proc/mtd@):

<pre>

dev:    size   erasesize  name

mtd0: 00020000 00020000 "boot"

mtd1: 07fe0000 00020000 "system"

mtd2: 0003f000 0001f800 "bootdata"

mtd3: 0003f000 0001f800 "unitdata"

mtd4: 0050b800 0001f800 "linux-A"

mtd5: 0050b800 0001f800 "linux-B"

mtd6: 00a17000 0001f800 "linux-R"

mtd7: 0150a800 0001f800 "rfs-A"

mtd8: 0150a800 0001f800 "rfs-B"

mtd9: 00a17000 0001f800 "app-A"

mtd10: 00a17000 0001f800 "app-B"

mtd11: 00a17000 0001f800 "data-A"

mtd12: 00a17000 0001f800 "data-B"

mtd13: 0003f000 0001f800 "bootdata_backup"

mtd14: 0003f000 0001f800 "caldata"

mtd15: 0003f000 0001f800 "caldata_backup"

mtd16: 0144d800 0001f800 "unitdata_backup"

</pre>

@boot@ is the bootloader partition. @system@ is an ubi partition, and remaining mtd partitions are in fact ubi volumes exposed as mtd device through gluebi.

@/etc/init.d/rcS@ uses the MTD numbers from @/etc/init.d/partnum.sh@:

<pre>

# MTD numbers

PARTNUM_BOOTDATA=2

PARTNUM_BOOTDATA_BKP=13

PARTNUM_KERNEL_A=4

PARTNUM_KERNEL_B=5

PARTNUM_KERNEL_R=6

PARTNUM_RFS_A=7

PARTNUM_RFS_B=8

PARTNUM_APP_A=9

PARTNUM_APP_B=10

PARTNUM_DATA_A=11

PARTNUM_DATA_B=12

PARTNUM_CALDATA=14

PARTNUM_CALDATA_BKP=15

PARTNUM_UNITDATA=3

PARTNUM_UNITDATA_BKP=16

# UBI offset

PARTNUM_UBI_OFFS=2

</pre>

h1. Partitions

h2. Systems

There are two systems: A and B.

They use one kernel (Linux), one root file system (standard Linux utilities), one application partition (containing all the femtocell/radio software), and one data partition (containing the operator specific configuration).

h2. Backup

The bootloader and both systems use common partitions: bootdata (for system selection and signatures), unidata (femtocell configuration), caldata (femtocell calibration).

They partition have backups in case the original are invalid (invalid data, can't be mounted, or signature check fails).

h2. Recovery

There is one recovery kernel, but this is only used for local maintenance (not remote) in case the two main systems are broken.

It doesn't download and flash any file automatically.

This is just a Linux kernel with SSH open (serial is also enabled, as opposed to the main OS where it is disabled).

@/etc/shadow@:

<pre>

root:$1$DJQchilX$y00cjFXXOulJnM7jqzcdP.:0:0:99999:7:::

user:$1$PFIa1uaF$kDzrucre2aHSSS8Bxtfv4.:15041:0:99999:7:::

manufop:$1$3Px2QUBG$xgh0jCSm//vPWkKjHUtgP/:15041:0:99999:7:::

</pre>