topic Re: Can I access to uboot variables from Linux? in T-Series

Can I access to uboot variables from Linux?

manoloruiz — Fri, 30 Sep 2016 06:34:29 GMT

Hi,

I would like to modify uboot variables from Linux. Is this possible? I have seen that it is possible to compile the kernel with some options in order to be able to access to them, but I cannot seen this option.

Target filesystem options  --->     [*] Das U-Boot Boot Monitor  --->         [*]   fw_printenv tool in target

Best regards

Re: Can I access to uboot variables from Linux?

mike_susen — Fri, 30 Sep 2016 06:38:45 GMT

Hi Manolo,

Yes you can access u-boot variables over Memory technology Device Layer (MTD). For detailed information you can see here HowCanIAccessUBootEnvironmentVariablesInLinux < DULG < DENX

Michal

Re: Can I access to uboot variables from Linux?

yipingwang — Fri, 30 Sep 2016 14:27:42 GMT

Hello manolo ruiz ,

I assume you use SDK 2.0, please refer to the following procedure.

Please add "u-boot-fw-utils" into variable IMAGE_INSTALL_append in meta-freescale/recipes-fsl/images/fsl-image-core.bb.

And run "bitbake fsl-image-core" to rebuild this tool into filesystem.

On the target board, please create a configuration file /etc/fw_env.config, the content like this

/dev/mtd5 0x60000 0x2000 0x100000

MTD device name
Device Offset
Environment Size
Flash sector size

Then execute "fw_printenv" and "fw_setenv" to read and write u-boot environment.

Have a great day,
Yiping

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Re: Can I access to uboot variables from Linux?

manoloruiz — Mon, 03 Oct 2016 10:21:58 GMT

Thanks for your answer. Is the answer also valid for SDK 1.9 and 1.8?

Best regards,

Manolo.

Re: Can I access to uboot variables from Linux?

yipingwang — Thu, 13 Oct 2016 07:00:19 GMT

Yes, it is valid for SDK 1.9 and 1.8.

Thanks,

Yiping

Re: Can I access to uboot variables from Linux?

gregjohnson — Tue, 24 Oct 2017 17:48:10 GMT

I performed these steps using the QorIQ SDK v2.0 and received the following errors:

$ bitbake fsl-image-core
Loading cache: 100% |########################################################################################################################################| ETA: 00:00:00
Loaded 3437 entries from dependency cache.
Parsing recipes: 100% |######################################################################################################################################| Time: 00:00:00
Parsing of 2733 .bb files complete (2729 cached, 4 parsed). 3438 targets, 248 skipped, 0 masked, 0 errors.
NOTE: Resolving any missing task queue dependencies
ERROR: Nothing RPROVIDES 'u-boot-fw-utils' (but /LS1020A/QorIQ-SDK-V2.0-20160527-yocto/sources/meta-freescale/recipes-fsl/images/fsl-image-core.bb RDEPENDS on or otherwise requires it)
ERROR: u-boot-fw-utils was skipped: Only config,images can be specified!
NOTE: Runtime target 'u-boot-fw-utils' is unbuildable, removing...
Missing or unbuildable dependency chain was: ['u-boot-fw-utils']
ERROR: Required build target 'fsl-image-core' has no buildable providers.
Missing or unbuildable dependency chain was: ['fsl-image-core', 'u-boot-fw-utils']

Does anyone know how to fix this?