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Yes, the Raspberry Pi 5 reads the EDID (Extended Display Identification Data) from the display, but it does not save it to a persistent file on the disk by default. Instead, the EDID is read from the monitor during boot and stored in system memory.

However, you can access and dump this information, or force the Pi 5 to use a custom EDID file.

How to Access the Active EDID
The active EDID can be read from the DRM (Direct Rendering Manager) sysfs interface.
Location: /sys/class/drm/card0-HDMI-A-1/edid or /sys/class/drm/card0-HDMI-A-2/edid for the second port.

Command to read: You can read the file directly, or use edid-decode to interpret it:
edid-decode /sys/class/drm/card0-HDMI-A-1/edid.

How to Save/Dump the EDID to a File

To capture the current EDID into a file for later use:

Use cat to dump the raw binary data:
cat /sys/class/drm/card0-HDMI-A-1/edid > /home/pi/monitor_edid.bin.

Alternatively, use the dump-active-edids script if using special distributions like LibreELEC, which saves files to /storage/.config/firmware/edid.

How to Use a Custom EDID File (Force EDID)
If you need to force a specific resolution (e.g., when the monitor is not correctly detected), you can tell the Raspberry Pi 5 to load an EDID file at boot.

1. Save the EDID to a file (as shown above).
2. Move the file to /lib/firmware/ (e.g., /lib/firmware/my_edid.bin).
3. Edit /boot/firmware/cmdline.txt to add the following parameter:
drm.edid_firmware=HDMI-A-1:my_edid.bin.
4. Reboot the Pi.

Note: For the Pi 5, ensure you are using the drm.edid_firmware method in cmdline.txt, as the older config.txt methods (hdmi_edid_file=1) are generally ignored by the new KMS driver.

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