EDID and KMS

[duby229]

what about setting the resolution on the kernel line in grub? It seems to only use the max supported by edid?

Also is there a user space utility for reading edid? there used to be one that worked in 32bit mode called read-edid but it doesnt work in 64bit. Is there any plan for something similar that will work with KMS? It would be real nice to be able towrite a script that reads the monitors edid info and then set the resolution before X is even started...

[agd5f]

IIRC, you can get the edid info from sysfs. Unfortunately, there is not a lot you can do for the fb console at the moment since the kernel fb interface doesn't support multi-head cards. Right now the console comes up in the preferred mode of the monitor or a supported clone mode if multiple monitors are present.

[amphigory]

Does anyone know if there are plans to allow modesetting from userspace? I have an EDID in Magnavox 1080p HDTV reporting wrong dot clock. I took a look at drm_edid.c in kernel tree but it doesn't look like the quirks addressed there would fix my issue.

Is there anywhere specific to report EDID quirks aside from the dev mailing lists?

X is working fine with custom modeline but fbcon is borked with KMS.

Here is the working X modeline:
"1920x1080@59" 146.0 1920 2008 2052 2200 1080 1084 1089 1125 +hsync +vsync

And here is EDID data reported:

saturn:~# get-edid | parse-edid 
parse-edid: parse-edid version 2.0.0
get-edid: get-edid version 2.0.0

    Performing real mode VBE call
    Interrupt 0x10 ax=0x4f00 bx=0x0 cx=0x0
    Function supported
    Call successful

    VBE version 300
    VBE string at 0xc01d8 "ATI ATOMBIOS"

VBE/DDC service about to be called
    Report DDC capabilities

    Performing real mode VBE call
    Interrupt 0x10 ax=0x4f15 bx=0x0 cx=0x0
    Function supported
    Call successful

    Monitor and video card combination does not support DDC1 transfers
    Monitor and video card combination supports DDC2 transfers
    0 seconds per 128 byte EDID block transfer
    Screen is not blanked during DDC transfer

Reading next EDID block

VBE/DDC service about to be called
    Read EDID

    Performing real mode VBE call
    Interrupt 0x10 ax=0x4f15 bx=0x1 cx=0x0
    Function supported
    Call successful

EDID claims 1 more blocks left


*********** Something special has happened!
Please contact the author, Matthew Kern
E-mail: pyrophobicman@gmail.com
Please include full output from this program (especially that to stderr)



Reading next EDID block

VBE/DDC service about to be called
    Read EDID

    Performing real mode VBE call
    Interrupt 0x10 ax=0x4f15 bx=0x1 cx=0x0
    Function supported
    Call successful

EDID claims 1 more blocks left
EDID blocks left is wrong.
Your EDID is probably invalid.
parse-edid: EDID checksum passed.

    # EDID version 1 revision 3
Section "Monitor"
    # Block type: 2:0 3:fc
    Identifier "MAGNAVOX TV"
    VendorName "PHL"
    ModelName "MAGNAVOX TV"
    # Block type: 2:0 3:fc
    # Block type: 2:0 3:fd
    HorizSync 30-75
    VertRefresh 56-62
    # Max dot clock (video bandwidth) 160 MHz
    # DPMS capabilities: Active off:no  Suspend:no  Standby:no

    Mode     "1920x1080"    # vfreq 60.000Hz, hfreq 67.500kHz
        DotClock    148.500000
        HTimings    1920 2008 2052 2200
        VTimings    1080 1084 1089 1125
        Flags    "+HSync" "+VSync"
    EndMode
    Mode     "1920x1080"    # vfreq 30.000Hz, hfreq 33.750kHz
        DotClock    74.250000
        HTimings    1920 2008 2052 2200
        VTimings    1080 1084 1089 1125
        Flags    "+HSync" "+VSync"
    EndMode
    # Block type: 2:0 3:fc
    # Block type: 2:0 3:fd
EndSection

Xorg:
(II) RADEON(0): EDID for output HDMI-0
(II) RADEON(0): Manufacturer: PHL  Model: d02a  Serial#: 16843009
(II) RADEON(0): Year: 2007  Week: 14
(II) RADEON(0): EDID Version: 1.3
(II) RADEON(0): Digital Display Input
(II) RADEON(0): Max Image Size [cm]: horiz.: 64  vert.: 36
(II) RADEON(0): Gamma: 2.20
(II) RADEON(0): No DPMS capabilities specified
(II) RADEON(0): Supported color encodings: RGB 4:4:4 YCrCb 4:4:4 
(II) RADEON(0): First detailed timing is preferred mode
(II) RADEON(0): redX: 0.632 redY: 0.324   greenX: 0.273 greenY: 0.591
(II) RADEON(0): blueX: 0.144 blueY: 0.068   whiteX: 0.280 whiteY: 0.285
(II) RADEON(0): Supported established timings:
(II) RADEON(0): 640x480@60Hz
(II) RADEON(0): 800x600@56Hz
(II) RADEON(0): 800x600@60Hz
(II) RADEON(0): 1024x768@60Hz
(II) RADEON(0): Manufacturer's mask: 0
(II) RADEON(0): Supported standard timings:
(II) RADEON(0): #0: hsize: 1280  vsize 1024  refresh: 60  vid: 32897
(II) RADEON(0): Supported detailed timing:
(II) RADEON(0): clock: 148.5 MHz   Image Size:  640 x 360 mm
(II) RADEON(0): h_active: 1920  h_sync: 2008  h_sync_end 2052 h_blank_end 2200 h_border: 0
(II) RADEON(0): v_active: 1080  v_sync: 1084  v_sync_end 1089 v_blanking: 1125 v_border: 0
(II) RADEON(0): Supported detailed timing:
(II) RADEON(0): clock: 74.2 MHz   Image Size:  640 x 360 mm
(II) RADEON(0): h_active: 1920  h_sync: 2008  h_sync_end 2052 h_blank_end 2200 h_border: 0
(II) RADEON(0): v_active: 1080  v_sync: 1084  v_sync_end 1089 v_blanking: 1125 v_border: 0
(II) RADEON(0): Monitor name: MAGNAVOX TV
(II) RADEON(0): Ranges: V min: 56 V max: 62 Hz, H min: 30 H max: 75 kHz, PixClock max 160 MHz
(II) RADEON(0): Number of EDID sections to follow: 1
(II) RADEON(0): EDID (in hex):
(II) RADEON(0):         00ffffffffffff00410c2ad001010101
(II) RADEON(0):         0e110103804024780ac1eca153469724
(II) RADEON(0):         11474923080081800101010101010101
(II) RADEON(0):         010101010101023a801871382d40582c
(II) RADEON(0):         450080682100001e011d801871382d40
(II) RADEON(0):         582c450080682100001e000000fc004d
(II) RADEON(0):         41474e41564f582054560a20000000fd
(II) RADEON(0):         00383e1e4b10000a2020202020200117

Working dot clock is 146.0 but EDID reports 148.5.

Thanks in advance!

[agd5f]

What kernel are you using kms from?

[amphigory]

2.6.33-rc7 at the moment. Also (not that it matters for framebuffer) running Debian unstable with Xorg 1.7.4. DRM, Mesa, and xf86-video-ati from master.

This is not a Radeon (RV620) specific issue. It also occurs with NVIDIA cards as well.

I'm using this box for MythTV and X is working fine with tear free Xv. fbcon isn't a big deal for me... just a little annoying when booting or troubleshooting with overscan on console.

Would you recommend an email to kernel dev responsible for EDID quirks? Or is there a mechanism in the works for manual modes specified via kernel parm?

[agd5f]

Would you recommend an email to kernel dev responsible for EDID quirks? Or is there a mechanism in the works for manual modes specified via kernel parm?

Yes send an email to dri-devel and file a bug on https://bugs.freedesktop.org

[amphigory]

Thanks! I posted here to see if anyone had a workaround or if my reasoning was unsound. I didn't want to needlessly distract kernel gods from pondering imponderables in the forest of source trees on Mount Olympus.