Raspberry Pi Kernels (2.0)

v3d will add Vulkan 1.1 support with Mesa 22.

ok, sway-21.10 fresh install, testing update fkms, NO sound speaker power on.

I found this issue tracker concerning vc4 and v3d in the mainline kernel that may be of interest to others.

Edit: It is a tracker for all related issues, not just videoā€¦ my interest was in the video info.

Is it better to run fkms or kms on the pi4b?

Depends on your use case. Some people like one over the other depending on the DE and custom configs. Experiment and see what you like.

fkms is installed by default as it has less issues all around. Pi OS does not do all of the DEā€™s like we do.

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my system works with the default fkms and no such editing of cmdline.txt to include the lines for the snd whateverā€¦ 1080p videos seem smoother than when using kms and those added snd edits. Lots of studder and loading wheels on screen.

If your are using the latest kernel in the repo you should not have to do the sound edits anymore it now knows which mode you are using. I have not seen any studder with glxgears.

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Ever wish you had a documented config.txt file?

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That is taken from RPiconfig - eLinux.org. Depending on how often that guy updates his git whether it stays current or not. The RPi offical documentation used to have a link to it as its source.

https://elinux.org/RPiconfig

Speaking of the RPi official config.txt documentation they have re-done it and it is really nice now loaded with some extra info/suggestions/caveats I have not seen before.

https://www.raspberrypi.com/documentation/computers/config_txt.html

During my travels this mourning I ran across a script to test the piā€™s stability with overclocking settings (also proper cooling as it tries to hit the fail safe fallback temp) you may have. It writes a large file trying to see if there will be corruption due to over voltage as some have had here in the past.

#!/bin/bash
#Test from https://elinux.org/RPiconfig
#Overclock_stability_test
#Simple stress test for system. If it survives this, it's probably stable.
#Free software, GPL2+

echo "Testing overclock stability..."

#Max out all CPU cores. Heats it up, loads the power-supply. 
for ((i=0; i<$(nproc --all); i++)); do nice yes >/dev/null & done

#Read the entire SD card 10x. Tests RAM and I/O
for i in `seq 1 10`; do echo reading: $i; sudo dd if=/dev/mmcblk0 of=/dev/null bs=4M; done

#Writes 512 MB test file, 10x.
for i in `seq 1 10`; do echo writing: $i; dd if=/dev/zero of=deleteme.dat bs=1M count=512; sync; done

#Clean up
killall yes
rm deleteme.dat

#Print summary. Anything nasty will appear in dmesg.
echo -n "CPU freq: " ; cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
echo -n "CPU temp: " ; cat /sys/class/thermal/thermal_zone0/temp
dmesg | tail 

echo "Not crashed yet, probably stable."
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The info in that text fileiss a bit varried from the post by darksky underneath it. Specifically hdmi modes are different.

I would go by the RPi link. They have what is supported for the piā€™s.

For my tv I use this for 1366x768 because of my eyes.

hdmi_mode:0=39
hdmi_group:0=2
hdmi_force_mode:0=1
hdmi_ignore_edid:0=0xa5000080

This for 1920x1080

hdmi_force_edid_3d:0=1
hdmi_mode:0=16
hdmi_group:0=1
hdmi_force_mode:0=1
hdmi_ignore_edid:0=0xa5000080
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Thank you for pointing that out, I will take a look.

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Tried this for my setting but after boot I got

vcgencmd get_config hdmi_mode
hdmi_mode is unknown

Same for group

Must mean my display canā€™t do what Iā€™m trying to make it do.

OK so i tried it again with your mode and got the same resultā€¦

I received 5.14.14-2-MANJARO-ARM ( Sun Oct 24 12:41:34 UTC 2021) without announcement.
Is it the same for you ?

hdmi_mode is unknown means that the option hdmi_mode to the command vcgencmd is unknown, not that the actual hdmi mode is unknown. You probably want tvservice.

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I did not find the discrepancy. The link to the config file consolidates the two hdmi mode tables into one so it looks different, but the settings and values seem to the be same. But maybe you are referring to something I did not look at? Is there a specific entry you could point me to?

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I am not really sure what you are trying to do or what the problem is if you have one.

When you manually set the mode it will boot in that mode if your setting are correct for your tv if not you will get a black or messed up screen. Some tvā€™s like mine will not provide the proper edid info for it to boot with the pi4 so I have to manually set the mode in config.txt.

CEA (group 1) is the standard typically used by tv's
DMT (group 2) is the standard typically used by monitors

If your tv provides the proper edid info to boot with video then there is a good chance you do not have to do a custom config in config.txt. Other wise you have to fiddle around with custom settings using what you tv is capable of using the guide as a reference. And yes you can experiment with the 2 different modes to get what you desire.

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Mode 63 is for 1080p at 120hz on darksys list but different on yours

Thank you for showing me that error.

Just trying to push 1080o at 120 hz