Linux Kernel 4.9 and a (not so) happy Jornada 720

And should have said in prior post, please feel free to ask questions, if you need help, I and others here will answer questions.

Hello!
Sorry for not answering, I was very busy with other things. I will try to answer all your questions!

@timo
I never did a benchmark with any CF card, but with the 128GB card from Transcend everything works fine. Please feel free to find a way to remap the keyboard with loadkeys, I have a few German keymap files for the Jornada but never had time to test them. If you like I can give you all the files.
And if you like to recompile programs for the Armv4 let us know if there is any diferrence.

I never did any patches, instead I did it the dirty way and changed the kernel source directly. Maybe I should make patches and send them to the ARM kernel mailing list ... However, I can send you the driver source files with my changes or the complete kernel source.

@can't remember
Please post the exact error message regarding sudo. The brightness problem after reboot has something to do with the brightness settings inside the ROM after a soft-reset. I thing it adds the start value to the current setting in Linux. Maybe you can find out more.

@joval
As mark mentioned, you can find my tutorial here: http://www.sp-net.at/wiki/doku.php?id=jornada_j720_devuanlinux


Regards
Stefan

@_dev-null: the exact error message is "sudo: error while loading shared libraries: /usr/lib/sudo/libsudo_util.so.0: file too short"

The brightness issue also happens with NetBSD 9.1, I'll see if I can find out more when I have more free time. Booting from a "bright" Windows CE back to Linux (or NetBSD) reverts the issue, so there's something during Linux boot that can actually fix/reset the brightness. Rebooting back to Windows CE results in too bright screen again.

Upon boot "cat /sys/devices/platform/jornada_bl/backlight/s1d13xxxfb/actual_brightness" returns -110 but after doing "echo 100 > /sys/devices/platform/jornada_bl/backlight/s1d13xxxfb/brightness" (or some other value) it starts returning positive numbers. So far setting a specific brightness or turning off the screen before rebooting didn't fix the brightness problem. I'll keep experimenting later.

Another issue I found is when I press the power button a few consecutive times the console starts spamming this error message: "SSP: timeout while waiting for transmit"

PS: I've got the path for the brightness slightly wrong on my previous post, it wasn't "/sys/devices/platform/jornada/jornada_bl", it is "/sys/devices/platform/jornada_bl"

Hello!
I will have a look into the sudo error...
In Linux the display driver resets the contrast to a default value during the boot process.
The issue with the power button happens because it tries to put the Jornada into sleep mode, and because you have no flashboard this doesnt work. You can bind this button to a "sleep" script that turns off the display backlight and PCMCIA Slot. Something similar happens in NetBSD if you press that button.

Regards
Stefan

Can any of you tell me where the fluxbox config file is located to make Stefan's changes ...what does ~/.fluxbox mean...I am not familiar with linux file storage nomenclature...and I can't see the menu applications . Also, when I bring up Netsurf through the command line it can't connect with the internet...is there something I'm missing ?? Thanks in advance.

Edited by joval 2020-11-25 12:05 AM

Hi!
"~" is your home directory, it is the same as "/home/user" and ".fluxbox" is a hidden folder inside your home directory.
So ~/.fluxbox is the full path to the directory where fluxbox stores the configuration files.
You can read about the contents of the .fluxbox directory here https://addy-dclxvi.github.io/post/my-fluxbox/#explanations

Stefan

Like _dev-null says, ~ is a shorthand for what in Windows is %USERPROFILE%. You can cd ~ to go to home just as you can cd %USERPROFILE% in Windows.
Any folder with a . prefix will auto hide, you can ls -a at the command line to see it though

Many thanks for your reply, Stefan. No worries re. the delay, I fried my RAM board anyway when trying the 128m upgrade, waiting for new ones from usedhandhelds now.

The Transcend 64m CF card worked well too, thanks to your instructions for adding its fingerprint to the kernel source.

Would be great if you could either post diffs for the drivers you patched or for the entire kernel tree. Maybe share on your website along with the binaries. So we could apply to a fresh source tree as a known good starting point.

Re the armv4 recompile, I started to look into open embedded which is a framework for building entire distros. I managed to build a very slim rootfs for armv4 with busybox which works under qemu emulation. If it works on the j720 too then could be a starting point to explore further, for example with a more efficient xserver.

Here is one thought on the sleep mode - let me know what you think:
As per the Intel cpu reference manual, the processor is reset after sleep, so it loses context and tries to start execute instructions from 0x0 which is in Rom. The code there always runs after reset, no matter if fresh power on or sleep. How does WinCE know the difference and where to resume after sleep? I guess there must be a specific memory location in RAM in which the CPU context (config and registers) is stored right before going to sleep and the ROM code probably inspects and restores it if valid to allow CE to resume exactly where it left off.
Now if we could store a similar CPU dump there from a running Linux before sleep, theoretically the ROM code should bring us back there after waking up. We‘d need to identify and somehow write protect that memory region from regular linux use, and we need to find out exactly how that dump has to look like, then I believe it could work.

Thanks
Timo

Archimark , what kind of adapter did you buy for you ambicom card?

Stefan, is this going to replace your normal usage of netbsd? I'm considering trying this linux distro you are creating or the netbsd one that you've previously worked on. Which would you say is makes for a more capable jornada at this point?

Edited by jorel101 2020-12-03 2:38 AM

Hi,

Bought this one:

https://www.ebay.com/itm/TYPE-II-Compact-Flash-PCMCIA-Adapter-FOR-MI...

Thanks, ordered one today!

Hi Mark
did you get the ambicom wL54 cf working as WPA?? Have a "how to" to follow ? Is it faster than the 11mbs cards? Thanks in advance!

posted on my J720....

Edited by joval 2020-12-04 5:03 PM

@ jorel101

You're welcome....hope it works for you.

@ joval

Unfortunately, got super busy with work and some personal matters the past month, so, haven't touched 720 for some time.

Should be able to test it tonight and report back....at work now....

Hi!
If you plan to buy a WL54-CF look out for a Rev. 2.1 or higher card! All older revisions do not work with the libertas driver.

My WL54 works, except from a problem with CRDA (because it is a card from the US and i tried to use AT as country code) so i need to do some hacks and recompile CRDA, but thats another story.
You need a few extra packages and a modified wpa_supplicant start command.

You need the following additional packages installed:

iw
firmware-libertas
crda

For this do the following steps:
You have to edit your sources.list

vi /etc/apt/sources.list

to this line "deb http://deb.devuan.org/merged ascii main" add "non-free" it should look like this:

deb http://deb.devuan.org/merged ascii main non-free

After that insert your ethernet card, or working wifi card (you need a internet connection) and do an apt update. Now you can install the required packages
apt install iw crda libertas-firmware

Now you should be able to use "iw" commands to connect to wifi networks.

https://wiki.debian.org/WiFi/HowToUse#Command_Line


For wpa_supplicant you have to use this command (first edit your wpa_supplicant.conf):

wpa_supplicant -i wlan0 -D nl80211 -c /etc/wpa_supplicant/wpa_supplicant.conf -B

@jorel101
Yes it replaces NetBSD on my Jornada. A LOT more pre compiled programs in the repos, a better community (better support) and as a long time Linux user I am far more comfortable to use it.


Stefan