Greg Kroah-Hartman
598cf27219
Link: https://lore.kernel.org/r/20260217200002.683975158@linuxfoundation.org Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Tested-by: Takeshi Ogasawara <takeshi.ogasawara@futuring-girl.com> Tested-by: Peter Schneider <pschneider1968@googlemail.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Salvatore Bonaccorso <carnil@debian.org> Tested-by: Brett A C Sheffield <bacs@librecast.net> Tested-by: Mark Brown <broonie@kernel.org> Tested-by: Luna Jernberg <droidbittin@gmail.com> Tested-by: Ronald Warsow <rwarsow@gmx.de> Tested-by: Justin M. Forbes <jforbes@fedoraproject.org> Tested-by: Ron Economos <re@w6rz.net> Tested-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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1.1 KiB
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28 lines
1.1 KiB
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.. SPDX-License-Identifier: GPL-2.0
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EDID
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====
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In the good old days when graphics parameters were configured explicitly
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in a file called xorg.conf, even broken hardware could be managed.
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Today, with the advent of Kernel Mode Setting, a graphics board is
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either correctly working because all components follow the standards -
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or the computer is unusable, because the screen remains dark after
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booting or it displays the wrong area. Cases when this happens are:
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- The graphics board does not recognize the monitor.
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- The graphics board is unable to detect any EDID data.
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- The graphics board incorrectly forwards EDID data to the driver.
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- The monitor sends no or bogus EDID data.
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- A KVM sends its own EDID data instead of querying the connected monitor.
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Adding the kernel parameter "nomodeset" helps in most cases, but causes
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restrictions later on.
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As a remedy for such situations, the kernel configuration item
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CONFIG_DRM_LOAD_EDID_FIRMWARE was introduced. It allows to provide an
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individually prepared or corrected EDID data set in the /lib/firmware
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directory from where it is loaded via the firmware interface.
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