Subject: NWSCONS design issue
To: None <tech-kern@netbsd.org>
From: Toru Nishimura <nisimura@is.aist-nara.ac.jp>
List: tech-kern
Date: 08/11/1998 19:36:25
Hi, I have been involved with NWSCONS for NetBSD/pmax. I've encountered
with a trouble with multiheaded configuration. My Q is; how can I
access to 2nd wsdisplay?
My development unit is Personal DECstation 5000/33 with one
TURBOchannel "smart framebuffer" option card. Because it has a
baseboard framebuffer builtin, the TURBOchannel option card is probed
as 'wsdisplay1' like below;
...
xcfb0 at tc0 slot 2 offset 0x0: 1024 x 768, 8bpp
wsdisplay0 at xcfb0
sfb0 at tc0 slot 0 offset 0x0: 1280 x 1024, 8bpp
wsdisplay1 at sfb0: console (std, dumb emulation)
...
Now I want to do wsconsio.h ioctl's with 'wsdisplay1' I looked at
sys/dev/wscons/wsdisplay.c and discovered questionable things in it.
Codes below make no sense to me;
#define WSDISPLAYUNIT(dev) (minor(dev) >> 8)
#define WSDISPLAYSCREEN(dev) (minor(dev) & 0xff)
#define WSDISPLAYMINOR(unit, screen) (((unit) << 8) | (screen))
Those expect device minor number is longer than 8 bit, which are not
relevant with NetBSD. Assuming this is an error, how can I open and
issue ioctls to the 2nd wsdisplay?
Tohru Nishimura
Information Technology Centre
Nara Institute of Science and Technology