By Gen8.5 do you mean Cherryview/Braswell?

We've not had a good solution for encoding the atom parts in the table.

For example, Ivybridge is Gen 7, Haswell is Gen 7.5, and Baytrail...doesn't have most of the features from Haswell (so it'd be Gen 7.1/2/3/4?) but also has features from Broadwell (so, Gen 7.6/7/8/9?).  It just didn't fit at all, so we left it as "7" and put in special cases for it.

I guess for Cherryview we could consider it Gen 8.<something>.

(In reply to Kenneth Graunke from comment #1)
> By Gen8.5 do you mean Cherryview/Braswell?
> 

Yes. Looking at the Bspec, it seems like CherryView actually isn't 8.5. 

> We've not had a good solution for encoding the atom parts in the table.
> 
> For example, Ivybridge is Gen 7, Haswell is Gen 7.5, and Baytrail...doesn't
> have most of the features from Haswell (so it'd be Gen 7.1/2/3/4?) but also
> has features from Broadwell (so, Gen 7.6/7/8/9?).  It just didn't fit at
> all, so we left it as "7" and put in special cases for it.
> 
> I guess for Cherryview we could consider it Gen 8.<something>.

I'm fine with giving it a decimal point if everyone agrees on an atom part naming scheme. Another possible solution is to modify brw_init_surface_formats(). I'm not yet sure what the best solution is.

This bug has been fixed with the following patch:

commit 59385da39dbe15dd4d1905953464b2fe34b07e16
Author: Nanley Chery <nanley.g.chery@intel.com>
Date:   Fri Oct 21 14:42:51 2016 -0700

    isl/format: Correct ASTC entries of format info table

    With the isl_format_supports* helpers, we can now conveniently
    report support for this format on Cherry View.

    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92925
    Signed-off-by: Nanley Chery <nanley.g.chery@intel.com>
    Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>