Bug 611149

I have a Sony GDM-400PS monitor that is about 15 years old. I have been using this monitor with Red Hat Linux 7.2 through Fedora 12, and have never had any issues with it.

I have been using KMS since it became the default (Fedora 12, I think). Again, no issues.

However, Fedora 13 does not care for this monitor.  Specifically, when the radeon driver loads at system boot, this error message appears in dmesg:

[drm:drm_edid_block_valid] *ERROR* EDID checksum is invalid, remainder is 48
[drm:drm_edid_block_valid] *ERROR* Raw EDID:
<3>50 df ff ff ff ff ff 00 4d d9 90 00 a6 2c 6b 00  P.......M....,k.
<3>1e 08 01 01 0e 25 1b 96 e8 0d c9 a0 57 47 98 27  .....%......WG.'
<3>12 48 4c ff ff 80 31 59 45 59 61 59 71 59 81 8f  .HL...1YEYaYqY..
<3>81 99 a9 40 a9 4f d6 09 80 a0 20 e0 2d 10 10 60  ...@.O.... .-..`
<3>a2 00 60 08 11 00 00 18 00 00 00 ff 00 37 30 32  ..`..........702
<3>33 37 38 32 0a 20 20 20 20 20 00 00 00 fc 00 47  3782.     .....G
<3>44 4d 2d 31 39 50 53 0a 20 20 20 20 00 00 00 fd  DM-19PS.    ....
<3>00 30 a0 1e 5f ff 00 0a 20 20 20 20 20 20 00 d1  .0.._...      ..

Because of this, I am limited to only very basic video modes (e.g., 1024x768 @ 60Hz).

I suspect one of two things is true:

1. The Sony GDM-400PS EDID is actually valid, but a bug was introduced in the radeon driver in F13 that causes it to mis-parse this particular EDID.

2. The Sony GDM-400PS EDID is invalid (and always has been), but the radeon driver only recently started complaining about it.

If #1 is the case, then, well, please fix.  ;-)

If #2 is the case... while I appreciate that the radeon driver now detects bogus EDIDs, this essentially cripples the functionality of my monitor. Please add a quirk/workaround for this particular monitor.

(I am a Fedora developer, and am well-versed in compiling kernels from SRPM. So, if you believe you have a fix for this, I'll be happy to test it.)