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diff --git a/Documentation/EDID/HOWTO.txt b/Documentation/EDID/HOWTO.txt deleted file mode 100644 index 539871c3b785..000000000000 --- a/Documentation/EDID/HOWTO.txt +++ /dev/null @@ -1,49 +0,0 @@ -In the good old days when graphics parameters were configured explicitly -in a file called xorg.conf, even broken hardware could be managed. - -Today, with the advent of Kernel Mode Setting, a graphics board is -either correctly working because all components follow the standards - -or the computer is unusable, because the screen remains dark after -booting or it displays the wrong area. Cases when this happens are: -- The graphics board does not recognize the monitor. -- The graphics board is unable to detect any EDID data. -- The graphics board incorrectly forwards EDID data to the driver. -- The monitor sends no or bogus EDID data. -- A KVM sends its own EDID data instead of querying the connected monitor. -Adding the kernel parameter "nomodeset" helps in most cases, but causes -restrictions later on. - -As a remedy for such situations, the kernel configuration item -CONFIG_DRM_LOAD_EDID_FIRMWARE was introduced. It allows to provide an -individually prepared or corrected EDID data set in the /lib/firmware -directory from where it is loaded via the firmware interface. The code -(see drivers/gpu/drm/drm_edid_load.c) contains built-in data sets for -commonly used screen resolutions (800x600, 1024x768, 1280x1024, 1600x1200, -1680x1050, 1920x1080) as binary blobs, but the kernel source tree does -not contain code to create these data. In order to elucidate the origin -of the built-in binary EDID blobs and to facilitate the creation of -individual data for a specific misbehaving monitor, commented sources -and a Makefile environment are given here. - -To create binary EDID and C source code files from the existing data -material, simply type "make". - -If you want to create your own EDID file, copy the file 1024x768.S, -replace the settings with your own data and add a new target to the -Makefile. Please note that the EDID data structure expects the timing -values in a different way as compared to the standard X11 format. - -X11: -HTimings: hdisp hsyncstart hsyncend htotal -VTimings: vdisp vsyncstart vsyncend vtotal - -EDID: -#define XPIX hdisp -#define XBLANK htotal-hdisp -#define XOFFSET hsyncstart-hdisp -#define XPULSE hsyncend-hsyncstart - -#define YPIX vdisp -#define YBLANK vtotal-vdisp -#define YOFFSET vsyncstart-vdisp -#define YPULSE vsyncend-vsyncstart |