Public bug reported:

Binary package hint: xserver-xorg-video-nv

In my case, "/usr/share/xserver-xorg/pci/nv.ids" was missing PCI-ID for
my 7600 GS AGP (10de:02e1). X server autodetection failed and -vesa was
used instead. By manualy adding appropriate PCI-ID to "nv.ids" and
restarting X server, autodetection worked like a charm and I didn't have
any problems with nv driver - changing resolution and refresh rate
worked.

I took some time to figure out what was realy going on here. It seems
that a large number of supported cards are affected by this bug. The
problem is the way "nv.ids" is generated. As far as I could tell, it's
generated from "nv_driver.c" (NVKnownChipsets[] to be exact) by a simple
awk+sed script. The problem is that not all PCI-IDs of supported cards
are listed there and therefore, "nv.ids" is missing PCI-IDs that are not
explicitely found in "nv_driver.c". Some supported cards, for example,
AGP versions of the cards where both AGP and PCI-E versions exist, are
handled diferently by the code.

Here is the code snippet from nv_driver.c:

    const CARD32 id = ((dev->device_id & 0xfff0) == 0x00F0 ||
                       (dev->device_id & 0xfff0) == 0x02E0) ?
                      NVGetPCIXpressChip(dev) : dev->vendor_id << 16 | 
dev->device_id;
    const char *name = xf86TokenToString(NVKnownChipsets, id);

So, cards with PCI-IDs 02Ex and 00Fx (AGP) are handled by translating
their PCI-IDs in PCI-E equivalent PCI-IDs and then looked up in
NVKnownChipsets[]. For example, PCI-IDs of my card, 02E1 is translated
to 0392, looked up in NVKnownChipsets[] and then handled properly.
NVGetPCIXpressChip() is used in the process and, as far as I could tell,
it's medling with registers to do its job. Even more supported cards are
handled by NVIsSupported() and NVIsG80() using bitmasks.

All in all, "nv.ids" is incomplete because of the way it's generated at
the moment.

Solutions:

1) Add supported PCI-IDs, 02Ex and 00Fx, to "nv.ids" manualy, after "nv.ids" is 
generated with awk+sed script. Consult "pci.ids" if needed.
2) Add supported PCI-IDs in NVKnownChipsets[] and then generate "nv.ids". Those 
entries in NVKnownChipsets[] would never be used by the code so the question is 
should they even be there.
3) Change how X server handle .ids files upstream, by adding support for 
whildcards/bitmasks. "nv.ids" would be generated differently. (ideal)

** Affects: xserver-xorg-video-nv (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: autodetection nv

-- 
nv, autodetection fails because of missing PCI-IDs, in nv.ids, for a large 
number of supported cards in Jaunty
https://bugs.launchpad.net/bugs/385703
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