Subject: Re: 1 Ghz CPU in AGP G4 causes NetBSD 1.6.2 hangs
To: None <port-macppc@netbsd.org>
From: Don Lee <MacPPC@caution.icompute.com>
List: port-macppc
Date: 09/28/2004 14:37:27
>Hi,
>
>A smarter ofwboot.xcf would not be a bad thing, thank you!
>
>>> From Don's original post:
>>
>> Sep 26 14:53:31 temp /netbsd: cpu0: HID0
>> 8450c0bc<EMCP,TBEN,NAP,DPM,ICE,DCE,SGE,
>> BTIC,LRSTK,FOLD,BHT>
>>
>> It would appear that power save mode is enabled. Could this be a possible
>> problem that would explain why a while(1) loop in the background makes all
>> the problems go away (i.e., it never naps)?
>
>Makes sense, but does that mean enabled, as opposed to just being a feature list?
>
>> Is anyone else running high end upgrade CPUs on their AGP G4s?
>
>Yes. I've tried two CPU upgrades. The one I wanted to use was a 1.4 GHz 7457 upgrade, but there are strange problems in NetBSD 2.0 which I could not isolate enough to know how to proceed further. It'd dump core in a number of different compiles, but in the same place in each of those compiles. I also tried OS X on the same hardware so I could confirm that both the memory and the CPU accelerator were not at fault.
>
>The second accelerator is a 1.3 GHz 7455, which works fine under 2.0:
>
>cpu0 at mainbus0: 7455 (Revision 3.3), ID 0 (primary)
>cpu0: HID0 8450c0bc<EMCP,TBEN,NAP,DPM,ICE,DCE,SGE,BTIC,LRSTK,FOLD,BHT>
>cpu0: 1300.00 MHz, 256KB L2 cache, 2MB no-parity L3 cache (PB2 SRAM) at 5:1 ratio
>
>I had to get the machine colocated, so I just went with the 7455, but I still have the 7457 and can try it out sometime, if anyone is interested in looking at the toolchain problems. The 7455 is quite stable.
>
>>> On this "upgraded" machine, the "while(1)" program running in the
>>> background makes the machine quite stable.  If I kill it, then
>>> the machine freezes up the next time I try to do any interesting
>>> network activity.  This seems to be the same with the 3Com and the gem
>>> (built-in) ethernet.
>
>That's strange. It does sound like some sort of strange power-save thing that NetBSD isn't controlling.
>
>John Klos

The other symptom is the *exactly* 10 ms ping times.  (corresponds to
the 100 Hz clock)  This also is present when
the while(1) is not running.  If the "nap mode" is doing something
odd, then I guess it could also be causing this, but my pet theory
is still some sort of race condition in the kernel......

I guess I should install NetBSD 2.0 and see how it behaves....

-dgl-