What OS are you using? With desktop version of RPiOS bookwork, it includes the hooks needed to handle dynamic attaching/detaching displays so this should just work.
Without that, you may need to handle this yourself.
If you only ever connect to the same display, you can capture the edid to a file and apply it with "drm.edid_firmware=<file>" and "video=HDMI-A-1:D".
You could try skipping the edid file and just using "video=HDMI-A-1:1920x1080M@60D" which may work, but assumes your monitor will be happy with the timing for that mode, and won't work with other hdmi features that rely on edid (e.g. switching resolutions, audio, CEC etc).
Without that, you may need to handle this yourself.
If you only ever connect to the same display, you can capture the edid to a file and apply it with "drm.edid_firmware=<file>" and "video=HDMI-A-1:D".
You could try skipping the edid file and just using "video=HDMI-A-1:1920x1080M@60D" which may work, but assumes your monitor will be happy with the timing for that mode, and won't work with other hdmi features that rely on edid (e.g. switching resolutions, audio, CEC etc).
Statistics: Posted by dom — Tue Apr 01, 2025 11:53 am