Subject: DSSI support RE: Now Ive gone and done it
To: Brian Chase <>
From: Chuck McManis <>
List: port-vax
Date: 10/05/2000 16:47:48
>On Thu, 5 Oct 2000, John Havard wrote:
> > All I know is that somebody had better get that internal DSSI controller
> > working.  [...]

At 05:24 PM 10/5/00 -0500, Brian Chase wrote:
>So it sounds like you're volunteering?

I've actually made some progress on this from the perspective of the KA640 
and the SII chip. My driver can attach to the SII chip and send commands 
through it to devices on the bus. It correctly sees that I have two disks 
attached. I manually kludged some code to send them the equivalent of the 
MSCP inquire command and they answer correctly. I've currently got three 
"hurdles" in front of me:
         1) Creating a device independent MSCP layer (this is what DEC
            calls the Class driver) I'm doing this now by teasing out
            the MSCP code from the current ra driver.
         2) Managing the private address space of the SII chip for DMA
            copies. Right now I essentially allocate one static buffer and
            copy into and out of it, this can and should be eliminated.
         3) Migrating this code to also work with the SHAC chip on the 4000/300
            and above series.

After I get past #2 I'll be ready to send code to Ragge or Matt for a code 
review and potential addition to the respository. Then start on #3.