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Return to U-Boot environment.

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Bootloaders

The bootloader environment configures the bootloader. Between reboots, the environment is stored with a checksum in the internal flash partition called "u-boot_env". On the bootloader console, there are bootloader commands for environment manipulation.

Typical environment

baudrate=115200
bootargs=rootfstype=jffs2 root=/dev/mtdblock4 console=ttySAC0,115200 console=tty0 loglevel=8 dyntick=enable lpj=252416
usbtty=cdc_acm
bootdelay=10
stdout=serial
stderr=serial
stdin=serial
mtdparts=mtdparts=neo1973-nand:0x00030000(u-boot),0x0000c000(u-boot_env),0x00200000(kernel),0x00130000(splash),0x03c94000(rootfs)
mtdids=nand0=neo1973-nand
bootargs_base=rootfstype=jffs2 root=/dev/mtdblock4 console=ttySAC0,115200 console=tty0 loglevel=8 dyntick=enable lpj=252416
bootcmd=setenv bootargs ${bootargs_base} ${mtdparts}; nand read.e 0x32000000 kernel; bootm 0x32000000
pcf50606_int1=0x40
filesize=160C000
partition=nand0,0
mtddevnum=0
mtddevname=u-boot

Timeouts

If the boot loader menu is on the screen, the phone will power off when there hasn't been activity for a while. This is not nice if you are working on the boot loader console, but you can make the time longer:

setenv boot_menu_timeout [seconds]

After the phone is powered on, there is a short period of time when you can connect to the console and cancel the automatic boot without going to the menu:

setenv bootdelay [seconds]

Menu

You can add items to the boot menu by setting environment variables of the form menu_<number> to values of the form <Title>: U-Boot-Commands.

For example the following command will add a boot menu entry that switches to autofast charging and turns off the backlight: setenv menu_6 Autofast-Charge and Backlight Off: neo1973 charger autofast\; neo1973 backlight off

While in this state, your Neo1973 can be charged with a generic USB charger. You also need to set boot_menu_timeout to 65000 to keep it from powering down, though.

Booting to the menu

To stop in the NAND menu, press and hold the AUX key after pressing the power button at startup. In recent versions of u-boot (builds from august 5 200?), you can also permanently enter the menu by setting the stop_in_menu environment variable to yes:

setenv stop_in_menu yes saveenv

to restore normal startup, unset this variable or set it to no.

Console

To get access to the bootloader console over USB with e.g., NeoCon, the following settings need to be made:

GTA01Bv2 # setenv stderr usbtty
GTA01Bv2 # setenv stdout usbtty
GTA01Bv2 # setenv stdin usbtty

See also