Michael Kukat <michael@camaronet.de> wrote:

>I didn't enable backup cache on the KA660. There is only about half a page on
>this, and i didn't find the addresses of the BCIDX and his friends. But the
>KA660 ist very fast, maybe the PROM enables bcache ?

I recall saying I'd look at the KA660 docs. I did look and you are right it
does have very little info. It does however say that the Bcache is controlled
by something called the C-chip. Now the VAX 4000-300 (KA670) has something
called the C-chip and looking at EK-KA670-TM I see a list of 10 IPRs used to
control this C-chip. The KA670 docs describe the backup cache in considerable
detail. IIRC, you did the KA670 support anyway, so try using the same code for
the KA660 backup cache. (It may well be that the console firmware initialises
the bcache and turns it on anyway - at least using the bcache control registers
you should be able to tell whether it is on or not!). If you don't have the
KA670 docs and don't have the info from anywhere else, let me know and I'll
desribe the KA670 stuff.

>But if you have the docs for the KA48, what is wrong here:

I don't really have any more to offer on the KA48 (4000-VLC). If you have time
to burn try:
	- Set DIAG in CCR
	- write cache TAG (just the tags, not the data)
	- leave BEHR alone
	- FLUSH in CCR
	- ENABLE in CCR and turn off DIAG

i.e. don't go testing anything, just write the tags and flush the cache.

Other than that, I have no idea.

Regards,

Antonio