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kme : edid   10

107583 – Linux: REGRESSION: drm: cmdline EDID override mechanisms broken since 4.15
There was a patch committed in the 5.2.x series at 48eaeb7664c76139438724d520a1ea4a84a3ed92. Did it land in 5.3, 5.4, ...?
linux  kernel  drm  kms  edid  sony  vaio  bootoption  graphics  annoyance  needshelp 
6 weeks ago by kme
Kernel Mode Setting (KMS) is great, but may not work as expected
The real solution is, thus, to optionally disable probing of the monitor and to directly feed appropriate monitor data into the kernel. For this purpose, the kernel configuration item CONFIG_DRM_LOAD_EDID_FIRMWARE was introduced. If enabled, the drm_kms_helper module will accept the parameter edid_firmware=, search for the given file in the /lib/firmware directory and use its data, if valid, to initialize the monitor timings of the graphics adapter as if it had been received from the monitor. Four standard timings are hard-coded in the driver and available immediately:

Resolution

Name

1024x768/60 Hz

edid/1024x768.bin

1280x1024/60 Hz

edid/1280x1024.bin

1680x1050/60 Hz

edid/1680x1050.bin

1920x1080/60 Hz

edid/1920x1080.bin

To force, for example, a screen resolution of 1280x1024/60 Hz, simply remove nomodeset from, add drm_kms_helper.edid_firmware=edid/1280x1024.bin to the kernel command, and enjoy a much faster screen and all the eye candy you missed so long.
linux  edid  kernel  graphics  driver  troubleshooting  maybesolution  vaio  vgcjs110j 
may 2017 by kme
EDID and HowTo make one
The key part below is that there is no corresponding file in /lib/firmware for these built-in modes.
KMS requires an EDID, and while you can override the EDID in org.conf, the plan is to get X11 away from the hardware and that will stop working. It is possible to override the EDID at the kernel level though. To do so, be sure CONFIG_DRM_LOAD_EDID_FIRMWARE is selected and passing drm_kms_helper.edid_firmware= one of the following 5 special parameters on the kernel command line, corresponding to the desired resolution:

edid/1024x768.bin
edid/1280x1024.bin
edid/1600x1200.bin
edid/1680x1050.bin
edid/1920x1080.bin

Note that these values are hardcoded in the driver, there is no corresponding /lib/firmware file (although if it exists it will override the built-in ones)

It is possible to create custom EDID if needed: see Documentation/EDID/HOWTO.txt in the kernel sources for the details.
video  linux  kernel  edid  troubleshooting  vaio  vgcjs110j  solution 
may 2017 by kme

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