Subject: some projections...

From: "David S. Miller" <[email-masked]>
Date: Tue, 21 May 1996 02:25:20 -0400

Iris SCSI driver: Mildly amusing, once I get the dma stuff straight
		  should be a 3 or 4 day affair to get going in an
		  initial working state.

Iris Ethernet driver: Cake walk, 3 nights tops.

It seems the HPC drives both of these devices in a similar manner, it
also seems that it has little state machines which do things like
retransmit collision packets on the SEEQ and various SCSI sequences as
well.  I need to get it straight in my head where the software driver
actually comes into play.  I like the HPC dma architecture btw.

Console driver: I assume the keyboard/mouse is driven off the Zilog
		uarts, if so this should be relatively simple as I can
		adapt most of the code from my Sparc stuff and how I
		layed that code out.  As for the screen I just need
		to figure out where the frame buffer lives and how to
		play with the palette registers and I'm set.  Also
		should be cakewalk to do serial console as well. This
		might be a 4 or 5 day job depending upon how things
		go initially.

So in less than two weeks I could have drivers for all the major
devices going already.

A large section of my work will be carefully going over the existing
code the linux-mips people have and putting together the initial
foundation so that I can at least start compiling kernels, then things
can run smoothly.

Yawn, stretch, more to come...

Later,
David S. Miller
[email-masked]

---

From: [email-masked] (William J. Earl)
Date: Mon, 20 May 1996 23:49:51 -0700

David S. Miller writes:
...
 > 		might be a 4 or 5 day job depending upon how things
...

    The keyboard and mouse, on the Indy and Indigo2, are driven by
a PS2-style keyboard and mouse controller.  Aside from the different 
way of addressing the registers, the driver should pretty much be the
same as the Linux PS2 keyboard and mouse controller.  

    The frame buffer is not directly addressable.  Most operations
are performed via commands written to the pixel pipeline, although
one can DMA pixels from main memory to the frame buffer.  I will
arrange for you to talk with the people who do IRIX X and GL
for Newport.

    It will probably be a good idea to boot up on a serial console
first, since the graphics interface is a bit more complex than a dumb
frame buffer.  That is how we usually port IRIX to a new system.
Since there are two serial ports, one can run the console on the first
port and the remote debugger on the second port, with very little
working beside the serial driver and bsaic exception handling
(assuming you start by booting using bootp() and the standard PROM).

---

From: "David S. Miller" <[email-masked]>
Date: Tue, 21 May 1996 02:52:55 -0400

Date: Mon, 20 May 1996 23:49:51 -0700
   From: [email-masked] (William J. Earl)

       The keyboard and mouse, on the Indy and Indigo2, are driven by
   a PS2-style keyboard and mouse controller.

Good, thanks.

Good idea, this will be the direction I go in then.  Although, I can't
wait to have Linux virtual consoles available on an SGI workstation ;-)

Later,
David S. Miller
[email-masked]