chknvm - Qualcomm Atheros PLC Image File Validator



chknvm - Qualcomm Atheros PLC Image File Validator


chknvm [options] file [file] [...]


Validate the image chain found inside a Qualcomm Atheros PLC firmware or parameter file by checking file structure, file size, image header sizes and checksums and image sizes and checksums. Optionally, display internal image header information or information extracted from selected image types, when present. Use this program to detect corrupted firmware or parameter files or inspect image files to determine content.

This program handles both the older Thunderbolt and Lightning and the newer Panther and Lynx firmware file formats. It validates files directly from disk and so it is slower than program chknvm2 but needs less memory at runtime.

This program is part of the Qualcomm Atheros Powerline Toolkit. See the AMP man page for an overview and installation instructions.



Print revision string identity fields in fixed-width columns. This option is useful when searching .nvm folders for a specific build.


Display manifest content, if present. The manifest is a special module, included in some image chains, that contains useful information about the chain. This option suppresses the summary ’looks good’ message.


Print firmware revision string on stdout. This option suppresses the summary ’looks good’ message.


Print SDRAM configuration block on stdout. This option automatically suppresses the summary ’looks good’ message.


Suppresses printing of routine messages. Specifically, it suppresses the summary ’looks good’ message.


Print additional information such as the image header for each image processed. This information can be used to distinguish one firmware file from another, if you know what to look for.


Print program help summary on stdout. This option takes precedence over other options on the command line.


Print program version information on stdout. This option takes precedence over other options on the command line. Use this option when sending screen dumps to Atheros Technical Support so that they know exactly which version of the Linux Toolkit you are using.



The name of an Atheros image file. By convention, Atheros Image files have a .nvm file extension but this program does not enforce this convention.


Qualcomm Atheros firmware file structure and content is proprietary to Qualcomm Atheros, Ocala FL USA. Consequently, public information is not available. Qualcomm Atheros reserves the right to change firmware file structure or content or change the name or behavior of any program that inspects or changes firmware files, in future software releases without any obligation to notify or compensate users of such programs.


This example reads file abc.nvm and validates it. The message shown indicates that the file is the correct length, image headers and images have the correct length and checksum and there are no read errors. The file can be have either the newer or older format.

# chknvm abc.nvm
abc.nvm looks good

The following example reads three files in succession and reports on each one. You can suppress good news with the -q option.

# chknvm INT6400.nvm AR7400.nvm AR7420.nvm
INT6400.nvm looks good
AR7400.nvm looks good
AR7420.nvm looks good

This next example displays the SDRAM parameter block found in the named files. SDRAM parameter blocks are a legacy feature. They were to configure memory. Powerline device now run a configuration applet, instead. Observe that file AR6400.nvm us the only one that contains SDRAM parameters.

# chknvm -s INT6400.nvm AR7400.nvm AR7420.nvm
------- INT6400.nvm (0) -------
SIZE=0x04000000 (64mb)

This next example prints the firmware revision string found inside older image files. The option can be used to identify the actual firmware image present when the filename has been changed. Newer image files have a manifest, instead. Observe that file AR7420.nvm shows no firmware revision string because it has the newer image file format.

# chknvm -r INT6400.nvm AR7400.nvm AR7420.nvm
INT6400.nvm (3) INT6000-MAC-4-1-4122-01-4020-20100219-FINAL
AR7400.nvm (5) INT7400-MAC-7-0-7011-01-52-20110811-FINAL

This example prints the manifest found inside newer firmware files. This can be used to distinguish firmware files from parameter files, determine exact firmware or parameter file revisions and so forth. Observe that we specified several files on the command line but only one file, AR7420.nvm, contained a mainfest.

# chknvm -m INT6400.nvm AR7400.nvm AR7420.nvm
------- AR7420.nvm (0) -------
Signature: 1234ABCD
Hardware Compatibility: AR74200
Chain Major Version: 0
Chain Minor Version: 1
Chain Type: Firmware
Build Major Version: 0
Build Minor Version: 0
Build Type: Special
Manifest Version: 1
Build Number: 0
Build Date: 20110811
Build Time: 203853
Device Type: 29728
Build Hostname: TOR-SW-SIM04
Build Username: buildbot
Build Description: Custom
Build Version String: AR-7420-FW-0_0-0_2-20110811:203853-buildbot:TOR-SW-SIM04-1-0_1


chknvm2(1), chkpib(1), chkpib2(1), int6ktest(7), nvmmerge(1), nvmsplit(1), plctest(1)


Charles Maier

Updated 2024-01-29 - |