Chrichri.ween.de
Chrichri.ween.de
Chris Vogel's microblog
not yet
✍️Write rieview ✍️Rezension schreiben 🏷️Get Badge! 🏷️Abzeichen holen! ⚙️Edit entry ⚙️Eintrag bearbeiten 📰News 📰Neuigkeiten
Tags:
Follow-up to this note.
Dragan had asked me to do repeated power-cycle tests with different kernel versions using the patched dtb for #RockPro64 to make sure the kernel #oops wouldn't still be an issue.
I learned that cutting the power of the device could kill the #LPDDR4 #RAM. This is documented in the specification referenced on the RockPro64 wiki page for Micron LPDDR4 Mobile LPDDR4 Datasheet as stated on page 37 in Uncontrolled Power-Off:
An uncontrolled power-off sequence can occur a maximum of 400 times over the life of the device.
I never had heard about this before! Cutting power without shutdown can kill my RAM?
To get all the debugging information I needed I wanted the system after booting to print dmesg to the serial console, wait a short time and then actually shutdown.
root:~# cat /root/bin/dmesg_and_shutdown.sh
#!/bin/bash
# a small script that outputs dmesg to serial
# console, waits 20 seconds and shuts down
dmesg > /dev/ttyS2
# show a message how to stop this script and wait 20 seconds
echo "Will shutdown in 20 seconds - to stop me call 'pkill dmesg_and_shut'" > /dev/ttyS2
sleep 20
echo "shutdown -h" > /dev/ttyS2
shutdown -h now
# a cronjob that runs after each boot
root:~# crontab -l
@reboot /root/bin/dmesg_and_shutdown.sh
I took the time needed for a complete cycle of booting, showing dmesg, waiting and shutting down: well below 2 minutes.
To automate the power cycle I used an #esp8266 based power switch made by #Sonoff (Powr2) running ESP Easy (mega-20210503).
#ESPeasy offers a simple scripting language I used to powercycle after 120 seconds of being switched on:
On System#Boot do
gpio,12,0
gpio,13,1
endon
On button#button_state do
if [blue_led#blue_led_state]=1
gpio,13,0
timerSet,1,2
else
gpio,13,1
gpio,12,1
timerSet,1,0
timerSet,2,0
endif
endon
On Rules#Timer=1 do
gpio,12,0
timerSet,2,1
endon
On Rules#Timer=2 do
gpio,12,1
timerSet,1,2
endon
Pressing the button on the Sonoff device toggles between:
minicom logged the serial output to a file.
Further down the #RabbitHole I went when looking at the resulting logfile…
10.3.2025 13:47Follow-up to this note. Dragan had asked me to do repeated power-cycle tests with different kernel versions using the patched dtb for...Follow-up to this note
Meanwhile Dragans changes to the dtb file helped my testing setup to boot without eMMC. So I could test booting manually from scsi devices like on my production system.
Looking for some simple instructions on how-to do this failed and I put together the following information.
u-boot on #RockPro64 uses variables written to flash. The important ones for choosing a device/kernel to boot:
# this u-boot will look for scsi devices only
boot_targets=scsi
# it will scan the devices for
bootcmd=bootflow scan
Since I have a boot.scr in my /boot the bootmeth seems to be script. There's also the source of that file boot.cmd available and from there I extracted the commands to run on the u-boot console to start any kernel/initrd/dtb I could find on disk:
# initialize pci bus
pci enum
# show devices on pci
pci
# reset bus and scan for scsi devices
scsi reset
# get partition table
scsi part
# find boot files
ls scsi 0:1 /boot
# load armbian defaults
load scsi 0:1 0x800800 /boot/armbianEnv.txt
# replace the xyz on the following line with the
# filesize output by 'load' above
env import -t 0x800800 xyz
# write uuid of partition to variable partuuid
part uuid scsi 0:1 partuuid
# arguments passed to the kernel on boot
setenv bootargs "root=${rootdev} rootwait rootfstype=${rootfstype} ${consoleargs} consoleblank=0 loglevel=${verbosity} ubootpart=${partuuid} usb-storage.quirks=${usbstoragequirks} ${extraargs} ${extraboardargs}"
# look for available images, initrds and dtbs
ls scsi 0:1 /boot
# get the dtb directory, **uInitrd** and the vmlinuz
# from the output to use with the following 'load' commands
load scsi 0:1 0x02080000 /boot/
load scsi 0:1 0x06000000 /boot/
load scsi 0:1 0x01f00000 /boot//rockchip/rk3399-rockpro64.dtb
booti 0x02080000 0x06000000 0x01f00000
At this point I only needed to wait for the Pine64 sata ctrl to arrive to test the current kernel with the same ctrl used in my production system.
So I went back to the fork in the tunnels and took the other way down the #RabbitHole…
9.3.2025 13:14Follow-up to this note Meanwhile Dragans changes to the dtb file helped my testing setup to boot without eMMC. So I could test booting...Follow-up to this note:
At one of the times the current #Armbian #linux kernel didn't crash, but booted on my #RockPro64 I installed #GotoSocial and yes: no more strange error messages running it. The only time I remember that I updated a linux kernel to make an application work.
Preparations to get the production system running with the newer kernel:
Meanwhile Dragan had patched the device tree and asked to check on a few reboots whether this would make a difference or cause any regressions.
Further down the #RabbitHole the tunnel forks…
7.3.2025 19:24Follow-up to this note: At one of the times the current #Armbian #linux kernel didn't crash, but booted on my #RockPro64 I installed...Follow-up to this note:
I decided to test whether #GotoSocial would work on the #RockPro64 using the current instead of the legacy #Armbian kernel before risking problems upgrading my production #yunohost.
I have a similar testing setup: old mechanical drives instead of SSDs, a different PCIe SATA controller, an additional eMMC.
The additional eMMC I need to boot from, because for some reason the PCIe SATA ctrl didn't work, when u-boot initializes the controller before the kernel.
Installing the current kernel on my testing setup I found it not working: no console on hdmi, no network. Forgot to install the newer dtb (device tree binary) as well.
With currrent kernel and dtb from #Armbian installed the system booted half of the times I switched it on. Asking around on the rock64 chat I met Dragan Simic who greatly helped me to get further down the #RabbitHole…
On my #yunohost I tried to update #gotosocial from 0.17.4~ynh1 to 0.18.1~ynh1 and the update failed.
GotoSocial just showed some cryptical error messages when started.
@dumpsterqueer@superseriousbusiness.org traced the problem back to a changed lib version used in the new GotoSocial version and the developer of the lib answered my #linux kernel would be too old.
The old #armbian legacy kernel is running, because … I don't remember.
I need a kernel update for my #rockpro64.
Down the #RabbitHole…
5.3.2025 19:11On my #yunohost I tried to update #gotosocial from 0.17.4~ynh1 to 0.18.1~ynh1 and the update failed. GotoSocial just showed some cryptical...unobtrusive good, mild, low on acid
Good to drink black without sugar.
#espressi by @QuijoteKaffee@mastodon.social
Inevitability rhetoric is a cunning fraud designed to render us helpless and passive in the face of implacable forces that are and must always be indifferent to the merely human
The Age of Surveillance Capitalism: The Fight for a Human Future at the New Frontier of Power
by Shoshana Zuboff
#SurveillanceCapitalism #privacy
3.3.2025 13:23 Inevitability rhetoric is a cunning fraud designed to render us helpless and passive in the face of implacable forces that are and must...A led light bulb (230V~) went dark in a room. By dark I mean that it dimmed down to very low light. No, I do not have a dimmer nor is it a light bulb with some fancy build-in iot stuff.
Two classic halogen bulbs didn't work in that socket. Testing the led bulb in a different socket it worked. I looked for contact problems and cleaned the contacts and the lamp seemed to work again using the led light bulb.
Then it went dark again and I decided to exchange the socket in the lamp. Opening the socket I found that in-between one of the cables and the socket an electronic part had been placed by soldering it to the end of the power line and fastening it to the socket.
I took out that part having never seen a stupid simple lamp coming with some small electric part build in. The lamp worked again with the all the bulbs I had tried.
Looking at for the specs I found this datasheet. It seems to be a resettable fuse or polymeric positive temperature coefficient device. I didn't know about these, but obviously the one I took out of the circuit seemed to have broken in a way that it switches too fast to a high resistance that only allows the led light bulb to glow dimly and isn't sufficient to drive a classic light bulb.
I guess the pptc has been put into the plastic lamp to protect it from heat: If a certain amount of power would be exceeded the light bulb used probably would emit too much heat for the lamp case. Still the lamp came with the usual label saying what light sources are allowed, but not stating any hint that it would not work with non-spec light sources or would contain active electronic parts.
The solutions once concocted by scholars of elk herds, sea turtles, and geese have been refurbished by surveillance capitalists and presented as an inevitable feature of twenty-first-century life on Earth. All that has changed is that now we are the animals
The Age of Surveillance Capitalism: The Fight for a Human Future at the New Frontier of Power
by Shoshana Zuboff
#SurveillanceCapitalism #privacy
19.2.2025 08:19 The solutions once concocted by scholars of elk herds, sea turtles, and geese have been refurbished by surveillance capitalists and...but the surest way to predict behavior is to intervene at its source and shape it
The Age of Surveillance Capitalism: The Fight for a Human Future at the New Frontier of Power
by Shoshana Zuboff
#SurveillanceCapitalism #privacy
16.2.2025 11:18 but the surest way to predict behavior is to intervene at its source and shape it The Age of Surveillance Capitalism: The Fight for a...60% Arabica - 40% Robusta. Intense, low acid, dark, strong. Just ordered another batch and am waiting to open the first bag. #favorites: I bought it again and again after trying others.
So... I ordered a new #battery pack for the #Xiaomi Dreame vacuum cleaner. It has not been an official replacement part, because I didn't find one. The battery worked for three month and then went flat.
Shortly after the vacuum cleaner stopped working and I put it on my #flohmarkt just in case someone would need replacement parts.
For all the rechargeable batteries in our household I had bought a charger that also #charges #LiIon and has options to measure the #capacity of cells.
These are the capacities of the #Samsung INR186050-25R cells I removed from the battery pack of the cleaner (mAh): 2366, 2294, 2262, 2254, 2321, 2267, 2257.
Looking at the #specs for the battery I found that the capacity should be 2500mAh. There's also a curve "20A discharge cycle life of 25R" that shows that a capacity of ~2200mAh is reached around charge cycle no. 150 of 250 cycles being tested. ~2300mAh is a value for around 100 charge cycles.
I'm wondering whether these cells can still be safely used in some other application.
Thanks a lot for all the work that went into the new #flohmarkt release 0.8.0!
The #yunohost app is upgraded as well and will soon appear in your update list.
If you can't wait: yunohost app upgrade --force flohmarkt.
@grindhold@23.social @midzer@chaos.social @stdevel@chaos.social
11.2.2025 19:18Thanks a lot for all the work that went into the new #flohmarkt release 0.8.0! The #yunohost app is upgraded as well and will soon appear in...We grow numb to these incursions and the ways in which they deform our lives. We succumb to the drumbeat of inevitability, but nothing here is inevitable. Astonishment is lost but can be found again
The Age of Surveillance Capitalism: The Fight for a Human Future at the New Frontier of Power
by Shoshana Zuboff
#SurveillanceCapitalism #privacy
10.2.2025 07:13 We grow numb to these incursions and the ways in which they deform our lives. We succumb to the drumbeat of inevitability, but nothing here...It's one of my #favorites. Sometimes it tasted just a tid too bitter, but usually very balanced.
People habituate to the incursion with some combination of agreement, helplessness, and resignation. The sense of astonishment and outrage dissipates. The incursion itself, once unthinkable, slowly worms its way into the ordinary. Worse still, it gradually comes to seem inevitable
The Age of Surveillance Capitalism: The Fight for a Human Future at the New Frontier of Power
by Shoshana Zuboff
#SurveillanceCapitalism #privacy
6.2.2025 11:35 People habituate to the incursion with some combination of agreement, helplessness, and resignation. The sense of astonishment and outrage...I need to reclaim some space on the wall of my office and decided to transfer my notes about #espressi I tried into my blog to be searchable by their tag for future reference.
If you do not want to receive these posts please filter out the hashtag #espressi.
If you do want to share your own, please go ahead and use that tag - I'll subscribe to it.
My preference is strong #espresso with little to no acid and a good balance of bitterness. I care a lot about the source and try to find beans that are traded in a way that values the work of the people growing the coffee.
Nearly all of the coffee I buy is labeled to be grown ecological and I'd strongly prefer beans grown in the shadow. So far I couldn't identify #shadegrown #coffee easily in Germany.
#flohmarkt is a tool to publish content in the form of a small ad / classified ad: on other fediverse services it scrolls by in the timeline. On a flohmarkt site it sticks in its place like a slip of paper containing a note on some bulletin board.
People can offer or search for services or goods. The federation radius irl across different flohmarkts can be limited by a distance setting.
Primary goal is to help people meet and exchange services, goods, opinions.
https://chrichri.ween.de/articles/dca424d/flohmarkt-a-federated-small-advertisement-server
5.2.2025 11:29@acockworkorange@mander.xyz #flohmarkt is a tool to publish content in the form of a small ad / classified ad: on other fediverse services...After some time the brackwater between glass and knob gets really annoying. Some models of lids already bring some openings already in their design. If not…
In my experience this doesn't work: switching. People will not do that. They just won't. It's the overwhelming majority that will not switch.
Maybe we need migration paths: let my FLOSS-chat talk to their evil surveillance capitalism driven chat.
I think that bridges are an important step to make people consider changing.
1.2.2025 11:18@delta@chaos.social In my experience this doesn't work: switching. People will not do that. They just won't. It's the...