re: kern/49290: DRMKMS fails to work with R300

[matthew green <mrg%eterna.com.au@localhost>]

The following reply was made to PR kern/49290; it has been noted by GNATS.

From: matthew green <mrg%eterna.com.au@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: kern-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
    netbsd-bugs%netbsd.org@localhost, roy%netbsd.org@localhost
Subject: re: kern/49290: DRMKMS fails to work with R300
Date: Sat, 07 Mar 2015 14:01:38 +1100

 turns out mlelstv's idea doesn't work.  in a normal case, vga@isa
 attaches as well, but is given wsdisplay1 and thus the problem
 does not occur.
 
 any attempts to map the VGA registers in the radeon@pci attach
 do not work for pc console setups (it does work for serial.)  this
 is because consinit() calls into vga and vga_init() before the
 copyright is printed, and the registers are mapped here.  (ie,
 attempting to map them in radeon@pci gives failure.)
 
 i attempted to create a "radeon@isa" to attach in preference, but
 even while i was able to do that eventually (relying on config
 "files*" files ordering to get radeon first, vga@isa would also
 attach.
 
 mlelstv and i played around with trying to get vga to properly
 detach but we were unable to get a working system yet.
 
 as such, we are going to, for now, remove vga@isa and
 pcdisplay@isa from GENERIC, and create a LEGACY kernel with those,
 for use by people with pre-PCI systems..
 
 
 there was an additional idea of moving vga@isa and pcdisplay@isa
 into modules, and having /boot load them only on systems that
 would require them.
 
 for the PRs, reference, also see:
 
 http://mail-index.netbsd.org/tech-kern/2015/02/28/msg018494.html
 
 and the subsequent thread.
 
 
 .mrg.