Via C3 support under FreeBSD

[J. Seth Henry]

Damian,
I have an older model of this system, a 933MHz C3 based on the Samuel2
CPU. I have didn't experience any problems with the kernel compile, and I
used a CPU type of 686 as well.

Remember, though; the VIA Cx processors are complete redesigns of the IA32
architecture, and it is quite likely they didn't emulate everything. I
wouldn't be surpised if some of the optimizations that hold true on a
"real" 6x86 class CPU break on a Cx CPU. By enabling both 586 and 686,
you may have turned off the incompatable optimizations. It is strange that
the kernel compiled clean on my box, though; given I have an older
generation of the CPU.

Also, most modern CPU's use the 686 cputype, not just the Pentium Pro's.
Pentium 3 and Pentium 4 both use it, as well as the AMD Duron/Athlon
CPU's (and I'm sure the latest cores are no different) I believe the 586
class CPU's were retired with the K6-2/3 series, and the first gen Pentium
processors, ending with the P5-266.

BTW - I figure you must have the M10000 everyone is tooting about. How
well does FreeBSD support the video subsystem on that board?

Good luck,
Seth Henry


Along similar lines...

I recently picked up a 1GHz Via C3 Ezra, and have been using it
successfully
with 4.8.  However, I had some troubles building world and kernel...

The CPU reports itself as a 686-class CPU.  So I set my make.conf
variables
appropriately (CPUTYPE=i686), and my kernel configuration file
appropriately
(machine i386, cpu I686_CPU), but I kept on getting Signal 4's whenever
doing a buildworld (in cc_tools) and buildkernel (on the first config
line).

So I dropped back down to 586, buildworld, buildkernel, reboot, and the
kernel started complaining that this processor class wasn't configured.  I
rebuilt the kernel using I586_CPU /and/ I686_CPU, and can run just fine.

Does anyone know any problems with the C3 and its CPU class?  Know why it
reports itself as a 686, but setting the 686 flag in make.conf causes a
Signal 4 on certain actions?  Or is the CPUTYPE=i686 reserved only for
Pentium Pro CPUs?

Snippet of "cd /usr/src ; make buildkernel KERNCONF=GENERIC":

    ===> GENERIC
    mkdir -p /usr/obj/usr/src/sys
    cd /usr/src/sys/i386/conf;

PATH=/usr/obj/usr/src/i386/usr/sbin:/usr/obj/usr/src/i386/usr/bin:/usr/obj/usr/src/i386/usr/
games:/sbin:/bin:/usr/sbin:/usr/bin
    config  -d /usr/obj/usr/src/sys/GENERIC
/usr/src/sys/i386/conf/GENERIC
    Illegal instruction (core dumped)
    *** Error code 132

    Stop in /usr/src.
    *** Error code 1

    Stop in /usr/src.

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