Re: sun4m cgfourteen sx wscons issues

[Michael <macallan%netbsd.org@localhost>]

Hello,

On Fri, 18 Apr 2014 17:46:55 +0200
victor%bubbleverse.eu@localhost wrote:

> On Thu, 17 Apr 2014 17:03:43 -0400
> Michael <macallan%netbsd.org@localhost> wrote:
> 
> > ftp://ftp.netbsd.org/pub/NetBSD/misc/macallan/sparc/netbsd.poteen.gz
> > this one does a little more explicit hardware setup ( on the cg14 side
> > ) instead of relying on OBP.
> 
> Same symptoms as before. However there is an interesting new line in dmesg:
> sx0: architecture rev. 27 chip rev. 0

I uploaded a new kernel with a possible fix:
ftp://ftp.netbsd.org/pub/NetBSD/misc/macallan/sparc/netbsd.poteen.gz

Background: SX instructions that reference memory are written to a
special address space with the same offset as the physical address they
reference, so one 32bit write transports effectively two 32bit values.
According to the manual the lower 3 bit of the address are ignored and
have to be added as an offset to the instruction itself.
On mine ( a rev. 25 ) that's exactly what happens, yours seems to
ignore instructions written to addresses that aren't 64bit aligned,
which would explain why every other column of characters is missing -
the font is 12 pixels wide. I bet you'd see either all or no characters
missing with an 8 bit wide font.
The new kernel just explicitly zeroes those bits.

have fun
Michael