how to get uboot shell (U - Boot>)

cancel
Showing results for 
Search instead for 
Did you mean: 

how to get uboot shell (U - Boot>)

3,036 Views
srinivasaporam
Contributor II

Hi,

We have got the I.MX6 reference board (Wandboard Quad). Serial port of this board is connected to Host PC which is running with Ubuntu and minicom. When we are powering the board, we are getting the messages. when it is asking for "Hit any key to stop autoboot" we are pressing spacebar/ESC. then it is stopping at =>. How to get the U-Boot shell (U-Boot>)

Please find the output of the minicom window as follows:

U-Boot 2014.04 (Jun 01 2014 - 21:28:55) armhf.com

CPU:   Freescale i.MX6Q rev1.2 at 792 MHz

Reset cause: POR

Board: Wandboard

DRAM:  2 GiB

MMC:   FSL_SDHC: 0, FSL_SDHC: 1

*** Warning - bad CRC, using default environment

In:    serial

Out:   serial

Err:   serial

Net:   FEC [PRIME]                                                            

Hit any key to stop autoboot:  0

=>

Labels (5)
Tags (1)
0 Kudos
3 Replies

443 Views
pranavmadhu
Contributor IV

Hi,

"=>" is the boot shell. You can see the boot script (u-boot environmental variables) by "printenv" command. To change a variable or to a new one use the "setenv" command. If you enter the "saveenv" command, then only your environmental variable saved on to your SD card, if the environment you added is only for testing or for one time boot, do not run the "saveenv" command. Running  "run bootcmd" will load your kernel, dtb etc if you stop normal boot.

0 Kudos

443 Views
jan_spurek
NXP Employee
NXP Employee

The "=>"  signalls, that you are in the U-Boot shell. It is the default prompt string. To change the prompt string, you must modify the CONFIG_SYS_PROMPT parameter and recompile.

0 Kudos

443 Views
jian_jiang
NXP Employee
NXP Employee

Hi,

It is the U-Boot shell.

E.g. you can input the following two commands to set the boot delay time to 5s.

=> setenv bootdelay 5

=> saveenv

All the best

Jian Jiang

-----------------------------------------------------------------------------------------------------------------------

PS: If my comment answers your question, please click Correct Answer button. Thank you!

-----------------------------------------------------------------------------------------------------------------------

0 Kudos