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-rw-r--r--Documentation/EDID/1024x768.S44
-rw-r--r--Documentation/EDID/1280x1024.S44
-rw-r--r--Documentation/EDID/1680x1050.S44
-rw-r--r--Documentation/EDID/1920x1080.S44
-rw-r--r--Documentation/EDID/HOWTO.txt39
-rw-r--r--Documentation/EDID/Makefile26
-rw-r--r--Documentation/EDID/edid.S261
-rw-r--r--Documentation/EDID/hex1
-rw-r--r--Documentation/kernel-parameters.txt15
9 files changed, 518 insertions, 0 deletions
diff --git a/Documentation/EDID/1024x768.S b/Documentation/EDID/1024x768.S
new file mode 100644
index 000000000000..4b486fe31b32
--- /dev/null
+++ b/Documentation/EDID/1024x768.S
@@ -0,0 +1,44 @@
+/*
+ 1024x768.S: EDID data set for standard 1024x768 60 Hz monitor
+
+ Copyright (C) 2011 Carsten Emde <C.Emde@osadl.org>
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License
+ as published by the Free Software Foundation; either version 2
+ of the License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+/* EDID */
+#define VERSION 1
+#define REVISION 3
+
+/* Display */
+#define CLOCK 65000 /* kHz */
+#define XPIX 1024
+#define YPIX 768
+#define XY_RATIO XY_RATIO_4_3
+#define XBLANK 320
+#define YBLANK 38
+#define XOFFSET 8
+#define XPULSE 144
+#define YOFFSET (63+3)
+#define YPULSE (63+6)
+#define DPI 72
+#define VFREQ 60 /* Hz */
+#define TIMING_NAME "Linux XGA"
+#define ESTABLISHED_TIMINGS_BITS 0x08 /* Bit 3 -> 1024x768 @60 Hz */
+#define HSYNC_POL 0
+#define VSYNC_POL 0
+#define CRC 0x55
+
+#include "edid.S"
diff --git a/Documentation/EDID/1280x1024.S b/Documentation/EDID/1280x1024.S
new file mode 100644
index 000000000000..a2799fe33a4d
--- /dev/null
+++ b/Documentation/EDID/1280x1024.S
@@ -0,0 +1,44 @@
+/*
+ 1280x1024.S: EDID data set for standard 1280x1024 60 Hz monitor
+
+ Copyright (C) 2011 Carsten Emde <C.Emde@osadl.org>
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License
+ as published by the Free Software Foundation; either version 2
+ of the License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+/* EDID */
+#define VERSION 1
+#define REVISION 3
+
+/* Display */
+#define CLOCK 108000 /* kHz */
+#define XPIX 1280
+#define YPIX 1024
+#define XY_RATIO XY_RATIO_5_4
+#define XBLANK 408
+#define YBLANK 42
+#define XOFFSET 48
+#define XPULSE 112
+#define YOFFSET (63+1)
+#define YPULSE (63+3)
+#define DPI 72
+#define VFREQ 60 /* Hz */
+#define TIMING_NAME "Linux SXGA"
+#define ESTABLISHED_TIMINGS_BITS 0x00 /* none */
+#define HSYNC_POL 1
+#define VSYNC_POL 1
+#define CRC 0xa0
+
+#include "edid.S"
diff --git a/Documentation/EDID/1680x1050.S b/Documentation/EDID/1680x1050.S
new file mode 100644
index 000000000000..96f67cafcf2e
--- /dev/null
+++ b/Documentation/EDID/1680x1050.S
@@ -0,0 +1,44 @@
+/*
+ 1680x1050.S: EDID data set for standard 1680x1050 60 Hz monitor
+
+ Copyright (C) 2012 Carsten Emde <C.Emde@osadl.org>
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License
+ as published by the Free Software Foundation; either version 2
+ of the License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+/* EDID */
+#define VERSION 1
+#define REVISION 3
+
+/* Display */
+#define CLOCK 146250 /* kHz */
+#define XPIX 1680
+#define YPIX 1050
+#define XY_RATIO XY_RATIO_16_10
+#define XBLANK 560
+#define YBLANK 39
+#define XOFFSET 104
+#define XPULSE 176
+#define YOFFSET (63+3)
+#define YPULSE (63+6)
+#define DPI 96
+#define VFREQ 60 /* Hz */
+#define TIMING_NAME "Linux WSXGA"
+#define ESTABLISHED_TIMINGS_BITS 0x00 /* none */
+#define HSYNC_POL 1
+#define VSYNC_POL 1
+#define CRC 0x26
+
+#include "edid.S"
diff --git a/Documentation/EDID/1920x1080.S b/Documentation/EDID/1920x1080.S
new file mode 100644
index 000000000000..36ed5d571d0a
--- /dev/null
+++ b/Documentation/EDID/1920x1080.S
@@ -0,0 +1,44 @@
+/*
+ 1920x1080.S: EDID data set for standard 1920x1080 60 Hz monitor
+
+ Copyright (C) 2012 Carsten Emde <C.Emde@osadl.org>
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License
+ as published by the Free Software Foundation; either version 2
+ of the License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+/* EDID */
+#define VERSION 1
+#define REVISION 3
+
+/* Display */
+#define CLOCK 148500 /* kHz */
+#define XPIX 1920
+#define YPIX 1080
+#define XY_RATIO XY_RATIO_16_9
+#define XBLANK 280
+#define YBLANK 45
+#define XOFFSET 88
+#define XPULSE 44
+#define YOFFSET (63+4)
+#define YPULSE (63+5)
+#define DPI 96
+#define VFREQ 60 /* Hz */
+#define TIMING_NAME "Linux FHD"
+#define ESTABLISHED_TIMINGS_BITS 0x00 /* none */
+#define HSYNC_POL 1
+#define VSYNC_POL 1
+#define CRC 0x05
+
+#include "edid.S"
diff --git a/Documentation/EDID/HOWTO.txt b/Documentation/EDID/HOWTO.txt
new file mode 100644
index 000000000000..75a9f2a0c43d
--- /dev/null
+++ b/Documentation/EDID/HOWTO.txt
@@ -0,0 +1,39 @@
+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 (1024x768, 1280x1024, 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 and
+replace the settings with your own data. The CRC value in the last line
+ #define CRC 0x55
+is a bit tricky. After a first version of the binary data set is
+created, it must be be checked with the "edid-decode" utility which will
+most probably complain about a wrong CRC. Fortunately, the utility also
+displays the correct CRC which must then be inserted into the source
+file. After the make procedure is repeated, the EDID data set is ready
+to be used.
diff --git a/Documentation/EDID/Makefile b/Documentation/EDID/Makefile
new file mode 100644
index 000000000000..17763ca3f12b
--- /dev/null
+++ b/Documentation/EDID/Makefile
@@ -0,0 +1,26 @@
+
+SOURCES := $(wildcard [0-9]*x[0-9]*.S)
+
+BIN := $(patsubst %.S, %.bin, $(SOURCES))
+
+IHEX := $(patsubst %.S, %.bin.ihex, $(SOURCES))
+
+CODE := $(patsubst %.S, %.c, $(SOURCES))
+
+all: $(BIN) $(IHEX) $(CODE)
+
+clean:
+ @rm -f *.o *.bin.ihex *.bin *.c
+
+%.o: %.S
+ @cc -c $^
+
+%.bin: %.o
+ @objcopy -Obinary $^ $@
+
+%.bin.ihex: %.o
+ @objcopy -Oihex $^ $@
+ @dos2unix $@ 2>/dev/null
+
+%.c: %.bin
+ @echo "{" >$@; hexdump -f hex $^ >>$@; echo "};" >>$@
diff --git a/Documentation/EDID/edid.S b/Documentation/EDID/edid.S
new file mode 100644
index 000000000000..ea97ae275fca
--- /dev/null
+++ b/Documentation/EDID/edid.S
@@ -0,0 +1,261 @@
+/*
+ edid.S: EDID data template
+
+ Copyright (C) 2012 Carsten Emde <C.Emde@osadl.org>
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License
+ as published by the Free Software Foundation; either version 2
+ of the License, or (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+
+/* Manufacturer */
+#define MFG_LNX1 'L'
+#define MFG_LNX2 'N'
+#define MFG_LNX3 'X'
+#define SERIAL 0
+#define YEAR 2012
+#define WEEK 5
+
+/* EDID 1.3 standard definitions */
+#define XY_RATIO_16_10 0b00
+#define XY_RATIO_4_3 0b01
+#define XY_RATIO_5_4 0b10
+#define XY_RATIO_16_9 0b11
+
+#define mfgname2id(v1,v2,v3) \
+ ((((v1-'@')&0x1f)<<10)+(((v2-'@')&0x1f)<<5)+((v3-'@')&0x1f))
+#define swap16(v1) ((v1>>8)+((v1&0xff)<<8))
+#define msbs2(v1,v2) ((((v1>>8)&0x0f)<<4)+((v2>>8)&0x0f))
+#define msbs4(v1,v2,v3,v4) \
+ (((v1&0x03)>>2)+((v2&0x03)>>4)+((v3&0x03)>>6)+((v4&0x03)>>8))
+#define pixdpi2mm(pix,dpi) ((pix*25)/dpi)
+#define xsize pixdpi2mm(XPIX,DPI)
+#define ysize pixdpi2mm(YPIX,DPI)
+
+ .data
+
+/* Fixed header pattern */
+header: .byte 0x00,0xff,0xff,0xff,0xff,0xff,0xff,0x00
+
+mfg_id: .word swap16(mfgname2id(MFG_LNX1, MFG_LNX2, MFG_LNX3))
+
+prod_code: .word 0
+
+/* Serial number. 32 bits, little endian. */
+serial_number: .long SERIAL
+
+/* Week of manufacture */
+week: .byte WEEK
+
+/* Year of manufacture, less 1990. (1990-2245)
+ If week=255, it is the model year instead */
+year: .byte YEAR-1990
+
+version: .byte VERSION /* EDID version, usually 1 (for 1.3) */
+revision: .byte REVISION /* EDID revision, usually 3 (for 1.3) */
+
+/* If Bit 7=1 Digital input. If set, the following bit definitions apply:
+ Bits 6-1 Reserved, must be 0
+ Bit 0 Signal is compatible with VESA DFP 1.x TMDS CRGB,
+ 1 pixel per clock, up to 8 bits per color, MSB aligned,
+ If Bit 7=0 Analog input. If clear, the following bit definitions apply:
+ Bits 6-5 Video white and sync levels, relative to blank
+ 00=+0.7/-0.3 V; 01=+0.714/-0.286 V;
+ 10=+1.0/-0.4 V; 11=+0.7/0 V
+ Bit 4 Blank-to-black setup (pedestal) expected
+ Bit 3 Separate sync supported
+ Bit 2 Composite sync (on HSync) supported
+ Bit 1 Sync on green supported
+ Bit 0 VSync pulse must be serrated when somposite or
+ sync-on-green is used. */
+video_parms: .byte 0x6d
+
+/* Maximum horizontal image size, in centimetres
+ (max 292 cm/115 in at 16:9 aspect ratio) */
+max_hor_size: .byte xsize/10
+
+/* Maximum vertical image size, in centimetres.
+ If either byte is 0, undefined (e.g. projector) */
+max_vert_size: .byte ysize/10
+
+/* Display gamma, minus 1, times 100 (range 1.00-3.5 */
+gamma: .byte 120
+
+/* Bit 7 DPMS standby supported
+ Bit 6 DPMS suspend supported
+ Bit 5 DPMS active-off supported
+ Bits 4-3 Display type: 00=monochrome; 01=RGB colour;
+ 10=non-RGB multicolour; 11=undefined
+ Bit 2 Standard sRGB colour space. Bytes 25-34 must contain
+ sRGB standard values.
+ Bit 1 Preferred timing mode specified in descriptor block 1.
+ Bit 0 GTF supported with default parameter values. */
+dsp_features: .byte 0xea
+
+/* Chromaticity coordinates. */
+/* Red and green least-significant bits
+ Bits 7-6 Red x value least-significant 2 bits
+ Bits 5-4 Red y value least-significant 2 bits
+ Bits 3-2 Green x value lst-significant 2 bits
+ Bits 1-0 Green y value least-significant 2 bits */
+red_green_lsb: .byte 0x5e
+
+/* Blue and white least-significant 2 bits */
+blue_white_lsb: .byte 0xc0
+
+/* Red x value most significant 8 bits.
+ 0-255 encodes 0-0.996 (255/256); 0-0.999 (1023/1024) with lsbits */
+red_x_msb: .byte 0xa4
+
+/* Red y value most significant 8 bits */
+red_y_msb: .byte 0x59
+
+/* Green x and y value most significant 8 bits */
+green_x_y_msb: .byte 0x4a,0x98
+
+/* Blue x and y value most significant 8 bits */
+blue_x_y_msb: .byte 0x25,0x20
+
+/* Default white point x and y value most significant 8 bits */
+white_x_y_msb: .byte 0x50,0x54
+
+/* Established timings */
+/* Bit 7 720x400 @ 70 Hz
+ Bit 6 720x400 @ 88 Hz
+ Bit 5 640x480 @ 60 Hz
+ Bit 4 640x480 @ 67 Hz
+ Bit 3 640x480 @ 72 Hz
+ Bit 2 640x480 @ 75 Hz
+ Bit 1 800x600 @ 56 Hz
+ Bit 0 800x600 @ 60 Hz */
+estbl_timing1: .byte 0x00
+
+/* Bit 7 800x600 @ 72 Hz
+ Bit 6 800x600 @ 75 Hz
+ Bit 5 832x624 @ 75 Hz
+ Bit 4 1024x768 @ 87 Hz, interlaced (1024x768)
+ Bit 3 1024x768 @ 60 Hz
+ Bit 2 1024x768 @ 72 Hz
+ Bit 1 1024x768 @ 75 Hz
+ Bit 0 1280x1024 @ 75 Hz */
+estbl_timing2: .byte ESTABLISHED_TIMINGS_BITS
+
+/* Bit 7 1152x870 @ 75 Hz (Apple Macintosh II)
+ Bits 6-0 Other manufacturer-specific display mod */
+estbl_timing3: .byte 0x00
+
+/* Standard timing */
+/* X resolution, less 31, divided by 8 (256-2288 pixels) */
+std_xres: .byte (XPIX/8)-31
+/* Y resolution, X:Y pixel ratio
+ Bits 7-6 X:Y pixel ratio: 00=16:10; 01=4:3; 10=5:4; 11=16:9.
+ Bits 5-0 Vertical frequency, less 60 (60-123 Hz) */
+std_vres: .byte (XY_RATIO<<6)+VFREQ-60
+ .fill 7,2,0x0101 /* Unused */
+
+descriptor1:
+/* Pixel clock in 10 kHz units. (0.-655.35 MHz, little-endian) */
+clock: .word CLOCK/10
+
+/* Horizontal active pixels 8 lsbits (0-4095) */
+x_act_lsb: .byte XPIX&0xff
+/* Horizontal blanking pixels 8 lsbits (0-4095)
+ End of active to start of next active. */
+x_blk_lsb: .byte XBLANK&0xff
+/* Bits 7-4 Horizontal active pixels 4 msbits
+ Bits 3-0 Horizontal blanking pixels 4 msbits */
+x_msbs: .byte msbs2(XPIX,XBLANK)
+
+/* Vertical active lines 8 lsbits (0-4095) */
+y_act_lsb: .byte YPIX&0xff
+/* Vertical blanking lines 8 lsbits (0-4095) */
+y_blk_lsb: .byte YBLANK&0xff
+/* Bits 7-4 Vertical active lines 4 msbits
+ Bits 3-0 Vertical blanking lines 4 msbits */
+y_msbs: .byte msbs2(YPIX,YBLANK)
+
+/* Horizontal sync offset pixels 8 lsbits (0-1023) From blanking start */
+x_snc_off_lsb: .byte XOFFSET&0xff
+/* Horizontal sync pulse width pixels 8 lsbits (0-1023) */
+x_snc_pls_lsb: .byte XPULSE&0xff
+/* Bits 7-4 Vertical sync offset lines 4 lsbits -63)
+ Bits 3-0 Vertical sync pulse width lines 4 lsbits -63) */
+y_snc_lsb: .byte ((YOFFSET-63)<<4)+(YPULSE-63)
+/* Bits 7-6 Horizontal sync offset pixels 2 msbits
+ Bits 5-4 Horizontal sync pulse width pixels 2 msbits
+ Bits 3-2 Vertical sync offset lines 2 msbits
+ Bits 1-0 Vertical sync pulse width lines 2 msbits */
+xy_snc_msbs: .byte msbs4(XOFFSET,XPULSE,YOFFSET,YPULSE)
+
+/* Horizontal display size, mm, 8 lsbits (0-4095 mm, 161 in) */
+x_dsp_size: .byte xsize&0xff
+
+/* Vertical display size, mm, 8 lsbits (0-4095 mm, 161 in) */
+y_dsp_size: .byte ysize&0xff
+
+/* Bits 7-4 Horizontal display size, mm, 4 msbits
+ Bits 3-0 Vertical display size, mm, 4 msbits */
+dsp_size_mbsb: .byte msbs2(xsize,ysize)
+
+/* Horizontal border pixels (each side; total is twice this) */
+x_border: .byte 0
+/* Vertical border lines (each side; total is twice this) */
+y_border: .byte 0
+
+/* Bit 7 Interlaced
+ Bits 6-5 Stereo mode: 00=No stereo; other values depend on bit 0:
+ Bit 0=0: 01=Field sequential, sync=1 during right; 10=similar,
+ sync=1 during left; 11=4-way interleaved stereo
+ Bit 0=1 2-way interleaved stereo: 01=Right image on even lines;
+ 10=Left image on even lines; 11=side-by-side
+ Bits 4-3 Sync type: 00=Analog composite; 01=Bipolar analog composite;
+ 10=Digital composite (on HSync); 11=Digital separate
+ Bit 2 If digital separate: Vertical sync polarity (1=positive)
+ Other types: VSync serrated (HSync during VSync)
+ Bit 1 If analog sync: Sync on all 3 RGB lines (else green only)
+ Digital: HSync polarity (1=positive)
+ Bit 0 2-way line-interleaved stereo, if bits 4-3 are not 00. */
+features: .byte 0x18+(VSYNC_POL<<2)+(HSYNC_POL<<1)
+
+descriptor2: .byte 0,0 /* Not a detailed timing descriptor */
+ .byte 0 /* Must be zero */
+ .byte 0xff /* Descriptor is monitor serial number (text) */
+ .byte 0 /* Must be zero */
+start1: .ascii "Linux #0"
+end1: .byte 0x0a /* End marker */
+ .fill 12-(end1-start1), 1, 0x20 /* Padded spaces */
+descriptor3: .byte 0,0 /* Not a detailed timing descriptor */
+ .byte 0 /* Must be zero */
+ .byte 0xfd /* Descriptor is monitor range limits */
+ .byte 0 /* Must be zero */
+start2: .byte VFREQ-1 /* Minimum vertical field rate (1-255 Hz) */
+ .byte VFREQ+1 /* Maximum vertical field rate (1-255 Hz) */
+ .byte (CLOCK/(XPIX+XBLANK))-1 /* Minimum horizontal line rate
+ (1-255 kHz) */
+ .byte (CLOCK/(XPIX+XBLANK))+1 /* Maximum horizontal line rate
+ (1-255 kHz) */
+ .byte (CLOCK/10000)+1 /* Maximum pixel clock rate, rounded up
+ to 10 MHz multiple (10-2550 MHz) */
+ .byte 0 /* No extended timing information type */
+end2: .byte 0x0a /* End marker */
+ .fill 12-(end2-start2), 1, 0x20 /* Padded spaces */
+descriptor4: .byte 0,0 /* Not a detailed timing descriptor */
+ .byte 0 /* Must be zero */
+ .byte 0xfc /* Descriptor is text */
+ .byte 0 /* Must be zero */
+start3: .ascii TIMING_NAME
+end3: .byte 0x0a /* End marker */
+ .fill 12-(end3-start3), 1, 0x20 /* Padded spaces */
+extensions: .byte 0 /* Number of extensions to follow */
+checksum: .byte CRC /* Sum of all bytes must be 0 */
diff --git a/Documentation/EDID/hex b/Documentation/EDID/hex
new file mode 100644
index 000000000000..8873ebb618af
--- /dev/null
+++ b/Documentation/EDID/hex
@@ -0,0 +1 @@
+"\t" 8/1 "0x%02x, " "\n"
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index d99fd9c0ec0e..7f084b764fb9 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -713,6 +713,21 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
The filter can be disabled or changed to another
driver later using sysfs.
+ drm_kms_helper.edid_firmware=[<connector>:]<file>
+ Broken monitors, graphic adapters and KVMs may
+ send no or incorrect EDID data sets. This parameter
+ allows to specify an EDID data set in the
+ /lib/firmware directory that is used instead.
+ Generic built-in EDID data sets are used, if one of
+ edid/1024x768.bin, edid/1280x1024.bin,
+ edid/1680x1050.bin, or edid/1920x1080.bin is given
+ and no file with the same name exists. Details and
+ instructions how to build your own EDID data are
+ available in Documentation/EDID/HOWTO.txt. An EDID
+ data set will only be used for a particular connector,
+ if its name and a colon are prepended to the EDID
+ name.
+
dscc4.setup= [NET]
earlycon= [KNL] Output early console device and options.