Linux/WL1837MOD: wireless_regdb regulatory implementation

Saumil Aggarwal

Part Number: WL1837MOD
Other Parts Discussed in Thread: WL1837

Tool/software: Linux

Hi,

I have a esom3730 board with TI wl1837 dual band wireless chip-set. I am on kernel 3.8.0. I am trying to use the calibrator tool for wl18xx testing following these instructions (http://processors.wiki.ti.com/index.php/WL18xx_TX_Testing) I have all the requirements needed compiled in my kernel and firmware image except CRDA.

I am using a yocto build environment and solving this task via kernel integration approach without crda.

CONFIG_CFG80211_INTERNAL_REGDB

If you do not want to install CRDA on a host, you can simply enable the CONFIG_CFG80211_INTERNAL_REGDB on your kernel. Once enabled you can place the db.txt from the wireless-regdb into net/wireless/db.txt. The downside to using this option is that you will need to rebuild your kernel for any regulatory updates, therefore using CONFIG_CFG80211_INTERNAL_REGDB is not recommended.

If using CONFIG_CFG80211_INTERNAL_REGDB without updating net/wireless/db.txt you'll end up with the static world regulatory domain, so if using CONFIG_CFG80211_INTERNAL_REGDB you should be sure to update net/wireless/db.txt otherwise you may end up spending a lot of time debugging an issue that does not exist. To help with this a patch has been sent to print a warning when a kernel has been built with CONFIG_CFG80211_INTERNAL_REGDB but the database is emtpy. If you happen to also have CONFIG_CFG80211_REG_DEBUG then compiling of the kernel will simply fail.

*****************---------------------------------------********************************

Basically I am building my kernel with INTERNAL_REGDB enabled. I pulled the latest db.txt from git repository and I could see the regulatory.bin file on my target.

However, when I issue a command "iw reg get" I get the following output

global
country 00: DFS-UNSET
(2402 - 2472 @ 40), (6, 20), (N/A)
(2457 - 2482 @ 40), (6, 20), (N/A), PASSIVE-SCAN
(2474 - 2494 @ 20), (6, 20), (N/A), NO-OFDM, PASSIVE-SCAN
(5170 - 5250 @ 160), (6, 20), (N/A), PASSIVE-SCAN
(5250 - 5330 @ 160), (6, 20), (0 ms), DFS, PASSIVE-SCAN
(5490 - 5730 @ 160), (6, 20), (0 ms), DFS, PASSIVE-SCAN
(5735 - 5835 @ 80), (6, 20), (N/A), PASSIVE-SCAN
(57240 - 63720 @ 2160), (N/A, 0), (N/A)

when I run "iw reg set US" , the country isn't set and I get the similar output.

The device is running an embedded yocto Linux.

Wondering if anyone came across the similar issue and have some comments to help with troubleshoot this issue?

over 6 years ago

0 Sudharshan KN over 6 years ago

TI__Genius 10550 points

Hi,

Can you please let me know the details of the testing? Is the issue you are facing is with the calibration tool or for the region setting? The calibrator tool is meant to check the HW in a production environment. i am not sure if country code setting is relevant as all the regulatory channels that is intended to be tested can be set through the calibration tool. Please let us know if you are facing issues with the calibration tool or with the country code setting.

Regards,

Sudharshan K N

0 Saumil Aggarwal over 6 years ago in reply to Sudharshan KN

Prodigy 50 points

Hi Sudharshan KN

I am having issue with region setting using "iw". Thoughts what it could be? Basically I was trying to set country and enable/disable freq channel and run the tool after.

I didn't know you could use the calibrator to set country. How do we do that? Any documentation other than the wiki link I posted above?

Saumil

0 Sudharshan KN over 6 years ago in reply to Saumil Aggarwal

TI__Genius 10550 points

Hi Saumil,

Have you compiled the kernel with the following settings CONFIG_NL80211_TESTMODE=y and you see the issue with the iw commands? Does the 'iw' commands work OK when the kernel is not configured with this mode? Pl confirm.

Regards,

Sudharshan K N

0 Saumil Aggarwal over 6 years ago in reply to Sudharshan KN

Prodigy 50 points

Yes I compiled the kernel with CONFIG_NL80211_TESTMODE=y and CONFIG_CFG80211_INTERNAL_REGDB=y. And have iw issues.

As you suggested, I rebuilt the kernel without those configurations and the "iw" command do not work as well. Its interesting because if I go back to a actual production image the iw set/get is not doing what its supposed to do.

-Saumil

0 Sudharshan KN over 6 years ago in reply to Saumil Aggarwal

TI__Genius 10550 points

HI Saumil,

Let me check this internally and get back to you.

Regards,

Sudharshan K N

0 Saumil Aggarwal over 6 years ago in reply to Sudharshan KN

Prodigy 50 points

Sure.

It looks like the TI wireless driver I have is built with crda support by default i.e the flag for INTERNAL_REGDB is not set inside the driver config.. Not sure yet.

0 Saumil Aggarwal over 6 years ago in reply to Saumil Aggarwal

Prodigy 50 points

Sudharshan KN, as I said in the previous reply about driver; the issue is resolved. The wl18xx driver is build by default with CRDA. So you have to go and change the config settings i.e disable crda, enable static regulatory database.

Note: Do not forget to copy db.txt from latest git commit at http://git.kernel.org/?p=linux/kernel/git/sforshee/wireless-regdb.git.

This should fix iw region setting issue.

Also, wondering if internally you guys have any extensive documentation for calibrator tool and maybe a download link?

Saumil

0 Sudharshan KN over 6 years ago in reply to Saumil Aggarwal

TI__Genius 10550 points

Hi Saumil,

Glad to know that the issue is resolved!! You can find details of the calibrator tool at the following location. Let me know if you can access this document

http://processors.wiki.ti.com/index.php/WL18xx_TX_Testing

Regards,

Sudharshan K N

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Linux/WL1837MOD: wireless_regdb regulatory implementation

CONFIG_CFG80211_INTERNAL_REGDB