Smap from EE

Guest · Post by **Guest** » Wed Apr 21, 2004 3:58 pm

Looking through PS2DRV code, it appears that the SMAP
and ATA devices can be controlled from the EE side. As I
mentioned in another posting, I have heard that indeed
this is the case, and that in fact the PS2Linux smap drivers
are done this way.

My question is, to what extent can the EE have full control
over the SMAP ? In other words, is there any requirement
that some work and/or initialization be done from the IOP,
or can I tell the IOP to get lost and let the EE handle everything
without the IOP touching a thing ?

For my application, as odd as it may sound, I want to avoid
the IOP entirely, and initially run networking from the EE. In
fact, I probably may have to completely reset the IOP to
ensure it does not interfere with the SMAP handling on the EE
side, but I am not positive how much concern there might be
in that area.

Only later on, when I have fully ported/bootstrapped the
code into a working state onto the EE, might I consider going
back to using the IOP for anything, but I don't want to be
worry about it at this stage.

Any advice will be appreciated,

Gorim

Post by **mrbrown** » Wed Apr 21, 2004 5:06 pm

The SMAP is connected to Dev9 which sits on the SBUS. Although the EE has some access to the SBUS, it cannot receive interrupts or use DMA to transfer to devices connected to the SBUS. As long as you don't plan on using interrupts or DMA you shouldn't have any problems accessing SMAP from the EE.

Post by **Oobles** » Wed Apr 21, 2004 8:00 pm

ps2ip is included in the new ps2sdk project and includes a full tcpip stack that uses the SMAP. It also includes a EE socket client which communicates with the IOP ps2ips.irx RPC server code.

This doesn't answer you question, but seeing as though a full tcpip implementation is available, I'm not sure why you'd want to get SMAP running form EE?

Oobles.

Guest · Post by **Guest** » Thu Apr 22, 2004 11:59 pm

Well, there are many reasons.

Actually, your post made me sit back and think in different
directions, and there are now things I might want to use in
ps2drv along the way.

Well, in answer to your question...

I want to do it from the EE because I haven't yet decided how
I want this application to interface with the IOP yet. So, I want
to minimize all interactions with the IOP. In fact, I envision
two forms of the app: one that can stand on its own in some
form, and one that can interface with the IOP.

However, thats merely in the finished product. To get there
along the way during development, I might want access to
IOP usb and network functions so I could at least have some
measure of console and network access during development.

As for PS2ip, great suggestion. Actually, my app already has
a builtin tcp/ip stack I want to keep. BUT, your suggestion
made me consider that I can easily make use of the higher
level SMAP network interface code on the iop, with some
minor mods. The devil is of course in the details.

Thanks for the suggestions!

Gorim