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Re: BogoMIPS working on DS5000/200 !

Subject: Re: BogoMIPS working on DS5000/200 !
From: Michael Engel <>
Date: Thu, 5 Dec 1996 05:21:31 +0100 (MET)
In-reply-to: <> from "Systemkennung Linux" at Dec 5, 96 03:08:50 am
> > the timer interrupt now seems to work well on the DS5000/200.
> (crowd is clapping, girls fall unconsious ...)

> > Now I'll try to adjust the HZ value to get a correct BogoMIPS number.
> > I'm currently using a timer interval of 64 Hz (15.625 ms) and set 
> > HZ to 64 in include/asm-mips/param.h [this _is_ the right place, I hope 
> > ...].
> That's a bit hacky.  <asm/param.h> is also used by userland.  So far
> we've used a value of 100 Hz.  Changing this will break all userland
> stuff which depends on that assumption.  I'll think about a solution.
This might be a real problem, as the DECstation can be either programmed
for 64 or 128 ticks per second (several other powers of 2 are also possible).

> > This shows us 3.11 BogoMIPS ... I don't think this is the correct value,
> > is it ? 
> I don't think so.  Have to read what the latency for a taken branch
> on the R3000 is.  Then I can say you what the theoretical value for
> BogoMIPS is.
I assume it is sufficient to set HZ according to the actual tick frequency,
right ? Or is there anything else that must be done ???

>> Btw., I forgot to mention that I indeed used pmax_printf in printk, so I got 
>> the BogoMIPS etc. printed. I changed printk to:
>> Bad hack, but actually works :-)
Well, it actually only works on the DS5000/20 :-). My 5000/2x doesn't like
that hack - no output ... I'll try to do it the right way ...

The DS5000/25 seems to have another problem with the interrupts:
I got the interrupts running, but have the same problem as one the 5000/200
before - the kernel refuses to continue after IRQs are turned on.
I'm running off a serial console terminal on the 5000/25. May this cause any
problems (I don't think so, but I'm not 100% sure) ?


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