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1.. SPDX-License-Identifier: GPL-2.02 3====4EDID5====6 7In the good old days when graphics parameters were configured explicitly8in a file called xorg.conf, even broken hardware could be managed.9 10Today, with the advent of Kernel Mode Setting, a graphics board is11either correctly working because all components follow the standards -12or the computer is unusable, because the screen remains dark after13booting or it displays the wrong area. Cases when this happens are:14 15- The graphics board does not recognize the monitor.16- The graphics board is unable to detect any EDID data.17- The graphics board incorrectly forwards EDID data to the driver.18- The monitor sends no or bogus EDID data.19- A KVM sends its own EDID data instead of querying the connected monitor.20 21Adding the kernel parameter "nomodeset" helps in most cases, but causes22restrictions later on.23 24As a remedy for such situations, the kernel configuration item25CONFIG_DRM_LOAD_EDID_FIRMWARE was introduced. It allows to provide an26individually prepared or corrected EDID data set in the /lib/firmware27directory from where it is loaded via the firmware interface.28