With chewitt 's help I've been operating an Odroid C2 on LE11 with some custom EDID modes (notably 1080p@24), because on 24fps material the system switched to 1080p60 (my sammy for some reason did not list 24/25/30 modes as possible, even though my old PS3 had no trouble switching to those modes). For the record, this is how it got solved.
Some days ago I updated to LE12 throwing the .img.gz file in the update directory. After the upgrade, I noticed something peculiar:
1) dmesg reported edid errors like the following:
[ 1.529684] meson-drm d0100000.vpu: Queued 1 outputs on vpu
[ 1.531544] stackdepot: allocating hash table of 131072 entries via kvcalloc
[ 1.538057] meson-drm d0100000.vpu: CVBS Output connector not available
[ 1.570520] meson-dw-hdmi c883a000.hdmi-tx: Detected HDMI TX controller v2.01a with HDCP (meson_dw_hdmi_phy)
[ 1.575699] meson-dw-hdmi c883a000.hdmi-tx: registered DesignWare HDMI I2C bus driver
[ 1.583241] meson-drm d0100000.vpu: bound c883a000.hdmi-tx (ops meson_dw_hdmi_ops)
[ 1.590162] [drm] forcing HDMI-A-1 connector on
[ 1.595739] [drm] Initialized meson 1.0.0 20161109 for d0100000.vpu on minor 0
[ 1.602137] meson-drm d0100000.vpu: Direct firmware load for edid/edid.bin failed with error -2
[ 1.610380] meson-drm d0100000.vpu: [drm] *ERROR* [CONNECTOR:32:HDMI-A-1] Requesting EDID firmware "edid/edid.bin" failed (err=-2)
[ 1.734276] meson-drm d0100000.vpu: Direct firmware load for edid/edid.bin failed with error -2
[ 1.737401] meson-drm d0100000.vpu: [drm] *ERROR* [CONNECTOR:32:HDMI-A-1] Requesting EDID firmware "edid/edid.bin" failed (err=-2)
[ 1.861616] meson-drm d0100000.vpu: Direct firmware load for edid/edid.bin failed with error -2
[ 1.864775] meson-drm d0100000.vpu: [drm] *ERROR* [CONNECTOR:32:HDMI-A-1] Requesting EDID firmware "edid/edid.bin" failed (err=-2)
[ 1.989376] meson-drm d0100000.vpu: Direct firmware load for edid/edid.bin failed with error -2
[ 1.989397] meson-drm d0100000.vpu: [drm] *ERROR* [CONNECTOR:32:HDMI-A-1] Requesting EDID firmware "edid/edid.bin" failed (err=-2)
[ 2.179711] Console: switching to colour frame buffer device 240x67
[ 2.217351] meson-drm d0100000.vpu: [drm] fb0: mesondrmfb frame buffer device
[ 2.224737] meson-drm d0100000.vpu: Direct firmware load for edid/edid.bin failed with error -2
[ 2.233075] meson-drm d0100000.vpu: [drm] *ERROR* [CONNECTOR:32:HDMI-A-1] Requesting EDID firmware "edid/edid.bin" failed (err=-2)
[ 2.234809] meson8b-dwmac c9410000.ethernet: IRQ eth_wake_irq not found
[ 2.251345] meson8b-dwmac c9410000.ethernet: IRQ eth_lpi not found2) Even though errors are listed in dmesg, 1080@24 material is played just fine. However, 23.976 material makes tv switch to 1080p60, whereas on LE11 it was played on 1080p24...
This does not make sense. If the custom EDID was not active, my Samsung would not switch at all to 1080p24 (ie even for 24fps material).
I'm attaching some information here, including my custom edid file.
modetest | paste -> https://paste.libreelec.tv/secure-shiner.log
dmesg | paste -> https://paste.libreelec.tv/ample-emu.log