Good news regarding tearing and low EmulationStation performance on Pi 4

roslof

@bluestang said in Good news regarding tearing and low EmulationStation performance on Pi 4:

MMAL is incompatible with the KMS driver. These are just msgs that are gracefully saying that it is incompatible.

Thanks bluestang. By chance, are you aware of a way to suppress these messages?

bluestang

@roslof said in Good news regarding tearing and low EmulationStation performance on Pi 4:

Thanks bluestang. By chance, are you aware of a way to suppress these messages?

Not really...there is ongoing work with the KMS video driver to support hw acceleration video decoding using V4L2 codecs. I believe Kodi is already using them...10-bit and 8-bit HDR hw video decoding are part of the KMS feature set.

MMAL is a Broadcom blob, whereas V4L2 is open-source API and is standard on Linux distros.

I failed to mention to you that using the KMS driver, as it currently stands, disables hw acceleration of video decoding. Eventually, this will be fixed in KMS but I don't see it as too big of a deal since I don't consume a lot of video media on my Pi4. Video snaps in ES typically are not that cpu intensive so it seems to be OK for the time being.

SaturnX

@roslof said in Good news regarding tearing and low EmulationStation performance on Pi 4:

@akamming said in Good news regarding tearing and low EmulationStation performance on Pi 4:
I noticed some errors on the console. Haven't noticed them before. The only change i lately did was the move to 5.4 using the kms driver. So i think it is related.
mmal: mmal_vc_component_create: failed to create component 'vc.ril.hvs' (1:ENOMEM) 
mmal: mmal_component_create_core: could not create component 'vc.ril.hvs' (1)
All works fine, dos anyone know what they mean and how to fix (or how they can be supressed, alle seems to work fine...)?
@akamming I just started tinkering with KMS and my console also displays these errors each time a video snap plays (using VLC). Like you, I'm having no visual/audio issues, but these errors appear on the console. The Interwebs were not much help. Were you ever able to find a solution?

@roslof @akamming I just moved my Pi4 onto the full KMS driver on kernel 5.10.17 and noticed the same errors on my console when I have video snaps on (VLC). Likewise, I don’t experience any audio/video issues and turning off video snaps and rebooting stops the errors.

Been trying to scour the web but nothing came up. Just wanted to share that I’m seeing the same and also looking for a solution.

bluestang

@saturnx

https://retropie.org.uk/forum/topic/25370/good-news-regarding-tearing-and-low-emulationstation-performance-on-pi-4/162?_=1616553266707

SaturnX

@bluestang ah thanks for that clarification!! Much appreciated.

GreenHawk84

I am honestly confused by this whole tearing thing because my Pi4 setup runs a lot of stuff pretty great, even PS1 games, but then Flycast had bad tearing (if you look at the floor of the stage in Soul Calibur). Yet, I see posts and videos raving about Dreamcast performance on Pi4. Is this really an issue for 100% of up-to-date Pi4 builds using all default drivers? It makes me want to start fresh again, which is a royal pain, just to see if something went sideways along the way.

quicksilver

@greenhawk84 flycast is especially jittery for me beyond just what normal screen tearing looks like. So I primarily use redream for dreamcast emulation.

Ranma

@greenhawk84
Once I set gpu_freq_min to 500 then Emulationstation didn't cause me any issues, but yes in the 3D emulation like Dreamcast and N64 you will still see tearing. The way around this I found was to go into the video settings and set G-Sync to on. This got rid of the tearing (for some reason!) and now it performs well. Don't set that for 8/16 bit stuff though or you'll see problems there (I found). There are other ways around this (such as setting kms in your config) but for now I prefer this approach until these problems are resolved.

ecto

@bluestang Hi, I just made the switch to kms / pulseaudio as by your tutorial some posts up.
Now I seem to have audio crackling with lr-* cores. The standalone emulators work well.

When I look into my syslog I find some errors. I don't know if it's related, though...

Apr 16 11:48:57 retropie kernel: [   15.082526] vc4_hdmi fef05700.hdmi: ASoC: error at snd_soc_dai_startup on fef05700.hdmi: -19
Apr 16 11:48:57 retropie kernel: [   15.125366] vc4_hdmi fef05700.hdmi: ASoC: error at snd_soc_dai_startup on fef05700.hdmi: -19
Apr 16 11:48:57 retropie kernel: [   15.125771] vc4_hdmi fef05700.hdmi: ASoC: error at snd_soc_dai_startup on fef05700.hdmi: -19
Apr 16 11:48:57 retropie kernel: [   15.126146] vc4_hdmi fef05700.hdmi: ASoC: error at snd_soc_dai_startup on fef05700.hdmi: -19
Apr 16 11:48:57 retropie kernel: [   15.131393] vc4_hdmi fef05700.hdmi: ASoC: error at snd_soc_dai_startup on fef05700.hdmi: -19
Apr 16 11:48:57 retropie kernel: [   15.131601] vc4_hdmi fef05700.hdmi: ASoC: error at snd_soc_dai_startup on fef05700.hdmi: -19
Apr 16 11:48:57 retropie pulseaudio[587]: E: [pulseaudio] module-alsa-card.c: Failed to find a working profile.
Apr 16 11:48:57 retropie pulseaudio[587]: E: [pulseaudio] module.c: Failed to load module "module-alsa-card" (argument: "device_id="1" name="platform-fef05700.hdmi" card_name="alsa_card.platform-fef05700.hdmi" namereg_fail=false tsched=no fixed_latency_range=no ignore_dB=no deferred_volume=yes use_ucm=yes card_properties="module-udev-detect.discovered=1""): initialization failed.

Also in the syslog, when I start retroach:

Apr 16 11:50:04 retropie kernel: [   68.619700] process 'emulators/retroarch/bin/retroarch' started with executable stack
Apr 16 11:50:07 retropie pulseaudio[587]: E: [alsa-sink-MAI PCM vc4-hdmi-hifi-0] alsa-sink.c: ALSA weckte uns auf, um neue Daten auf das Gerät zu schreiben, doch es gab nichts zum Schreiben!
Apr 16 11:50:07 retropie pulseaudio[587]: E: [alsa-sink-MAI PCM vc4-hdmi-hifi-0] alsa-sink.c: Dies ist höchstwahrscheinlich ein Fehler im ALSA-Treiber »vc4«. Bitte melden Sie diesen Fehler den ALSA-Entwicklern.
Apr 16 11:50:07 retropie pulseaudio[587]: E: [alsa-sink-MAI PCM vc4-hdmi-hifi-0] alsa-sink.c: Wir wurden durch das POLLOUT-Set geweckt, allerdings lieferte ein anschließender snd_pcm_avail() den Wert 0 oder einen anderen Wert < min_avail

Sorry to bother you. I also looking for a fix.

bluestang

@ecto can you give me details about your setup? 32-bit or 64-bit? Is it fully updated via apt? What steps did you take to enable the KMS driver? What does your boot config look like?

ecto

@bluestang Yeah, sure!

I have a 32bit setup and before switching to kms I did:

apt update 
apt full-upgrade

I also edited vc4-hdmi.conf.

I have now the kernelversion

Linux retropie 5.10.17-v7l+ #1403 SMP Mon Feb 22 11:33:35 GMT 2021 armv7l GNU/Linux

with the following config.txt:

disable_overscan=1
disable_splash=1

over_voltage=6
arm_freq=2100
gpu_freq=750
v3d_freq=800
hdmi_enable_4kp60=1

[pi4]
dtoverlay=vc4-kms-v3d
max_framebuffers=2

[all]
overscan_scale=1
hdmi_ignore_cec_init=1
dtparam=i2c_arm=on
enable_uart=1

Im reading this thread but haven't found an answer yet.

EDIT
There is something strange going on: The PSX games I testd crackled because they are running much too fast! I haven't seen any settings relating to that in retroarch, but I previously haven't noticed that.

Also the buttonmap of my joypad (xbox360) has changed?!? But that might have something to do with my retroarch update... I (once again) made too many changes at one, I guess ^_^;

roslof

@ecto said in Good news regarding tearing and low EmulationStation performance on Pi 4:

Im reading this thread but haven't found an answer yet

Shouldn't dtoverlay=vc4-kms-v3d read as dtoverlay=vc4-kms-v3d,noaudio?

ecto

@roslof I thought that noaudio should be omitted, but I'll try it.

bluestang

@roslof said in Good news regarding tearing and low EmulationStation performance on Pi 4:

@ecto said in Good news regarding tearing and low EmulationStation performance on Pi 4:

Im reading this thread but haven't found an answer yet

Shouldn't dtoverlay=vc4-kms-v3d read as dtoverlay=vc4-kms-v3d,noaudio?

@ecto

The noaudio option is if you want to continue to run the Broadcom firmware audio driver. The KMS driver is not only a video driver but also an audio HDMI driver as well.

It is purely up to the user which audio output they want.

bluestang

@ecto the audio crackling sounds like an issue with RetroArch specifically. What did you update with it? RetroPie is still on version 1.8.9...

ecto

@bluestang I just updated retroarch with retropie_setup so that should be ok. Let me check ...

believing the data from /opt/retropie/emulators/retroarch/retropie.pkg its on 1.8.8. I will have to shoo away the kids from the TV to check it on thr pi... ;)

ecto

@roslof OK I tried thenoaudiooption, and have indeed no audio in any emu. :(

But when trying lr-pcsx, it runs at normal speed! As soon as I remove thenoaudiooption, audio is back, but lr-pcsx runs too fast and has the crackling.
So far, I've tested amiberry (runs ok), scummvm (runs ok) and redream (runs ok)... sooo it's probably a retroarch/pulseaudio problem (as can also be seen in the syslog I posted earlier).

What I haven't done (I read here about that): start the desktop (as I have none) to change the audio output...

EDIT
Ok, I forgot to run the mixer setup in the retropie setup. I now have non-stuttering (non-kms) sound and the emus run at a normal speed.
I still have an error message that some mixer element couldn't be found, but anyhow.

Ranma

@ecto
I thought gpu_freq was not needed on the Pi 4 as per this -

"It is recommended when overclocking to use the individual frequency settings (isp_freq, v3d_freq etc) rather than gpu_freq, as since it attempts to set core_freq (which cannot be changed on the Pi 4), it is not likely to have the desired effect."
from here . https://www.raspberrypi.org/documentation/configuration/config-txt/overclocking.md

I only set v3d_freq myself on my Pi 400 and it performs well. Dunno, but could it be causing your problem? Also, I could have sworn I read here somewhere that the noaudio option was no longer needed. If I find this I'll post back.

ecto

@ranma Thanks for looking into that. I have somewhat solved my problem (see my edit some posts above).
You are probably right about the overclocking, but as I never had problems with these settings, I will just let them be ;)

bluestang

@ecto In RetroArch, do you have alsathread selected as your audio driver?