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1. minute (mntmn@mastodon.social)'s status on Saturday, 01-Apr-2023 02:04:39 JST minute

   maybe i'm holding it wrong but the rpi4 GPU seems slower than the imx8mq's gc7000? runs at max 650mhz?

   • James Just James (purpleidea@mastodon.social)'s status on Saturday, 01-Apr-2023 03:04:30 JST James Just James

     in reply to

     @mntmn I don't know about gc7000, but IIRC in the raspi-config utility you can set some overclock settings (for CPU or GPU I forget which) and GPU memory size. HTH

   • Adrián Pérez (aperezdc@mastodon.social)'s status on Saturday, 01-Apr-2023 03:06:29 JST Adrián Pérez

     in reply to

     @mntmn I can confirm this, the VideoCore GPU was a-okay in the times of the RaspberryPi 2 & 3 and has a few niceties (like plenty of KMS planes, with support for hardware video decoding directly onto them) but it definitely struggles with certain workloads. For example it's impossible to hit 60Hz if you do complaining (e.g. run a Wayland compositor) and there are big surfaces which need pixel format conversion (e.g. tiled to linear). If one can hit direct scanout it can work decently.

   • minute (mntmn@mastodon.social)'s status on Saturday, 01-Apr-2023 03:39:58 JST minute

     in reply to

     • Adrián Pérez

     @aperezdc oh, these are great insights, thanks!

   • Adrián Pérez (aperezdc@mastodon.social)'s status on Saturday, 01-Apr-2023 03:39:59 JST Adrián Pérez

     in reply to

     @mntmn in the RaspberryPi 4 the GPU has not evolved as much as the ARM cores, so for example H.264 decoding tends to go smoother in software because the status of V4L2 support is a bit spotty. Even for stateless decoders (which tend to work better) it's impossible to make e.g. the same video loop seamlessly when it reaches the end (there's a noticeable amount of milliseconds of decoder stall while restarting the video stream).

   • Adrián Pérez (aperezdc@mastodon.social)'s status on Saturday, 01-Apr-2023 03:53:17 JST Adrián Pérez

     in reply to

     @mntmn no problem at all!