Ok I am starting to dig into these and figure out what needs to happen to get the ppc targets working again.
The hardest case currently appears to be the sandpointx3 with pmc processor modules, so I will get to it last. The whole northboard/southboard thing is interesting. But something we need to handle. I think I have heard of the same thing with a few hypertransport based systems as well. Which board is the bootrom that the systems starts executing with on. The few schematics I have looked up so far have a bootrom on the sandpoint and the MPCxxx pmc module. The other datapoint I need to track down is are there other boards the processor pmc modules can plug into. Or there tighter coupling than that.
I have not been able to track down documentation on cpu the embeddedplanet epc405 is using. In fact I'm not even certain which cpu it is using which is part of the problem. Does that board use a northbridge at all or is the memory controller and pci bus built into the cpu?
But it looks like I have tracked down enough information on the totalipact/briq, to understand what is going on. Or at least well enough that I can get something that will build and will be close to working built. So I am starting there despite the fact it does not look like that port was ever quite finished, or at least it was never built to handle the general case as it has a hardcoded memory size.
One of the cases the northboard/southboard thing brings up is that we don't have good infrastructure for handling plugin boards with lots of chips that need special handling. If we can identify them we can do something, the code is just not very general yet. It is likely we want to be able to build a static device tree that describes a pluging board that we can just graft to the main tree when we detect that board. It is something to think about anyway.
Eric
Just a progress update before I go to bed.
I have the totalimpact/briq building now. There are a couple of things that are not quite right but nothing architectural.
Looking at where the code is I should be able to get the sandpointx3+pmc/altimus/mpc7410 building. Since there is only one pmc supported things look much simpler :)
Beyond that a lot of my confusion has been looking at code and expecting it to work, or to handle the general case when in fact it doesn't.
As I settle for merely fixing the code so it continues to do what it did before, I can successfully make a lot of progress.
Eric
On Nov 18, 2004, at 6:13 AM, Eric W. Biederman wrote:
Just a progress update before I go to bed.
I have the totalimpact/briq building now. There are a couple of things that are not quite right but nothing architectural.
Looking at where the code is I should be able to get the sandpointx3+pmc/altimus/mpc7410 building. Since there is only one pmc supported things look much simpler :)
Beyond that a lot of my confusion has been looking at code and expecting it to work, or to handle the general case when in fact it doesn't.
As I settle for merely fixing the code so it continues to do what it did before, I can successfully make a lot of progress.
Eric
The problem with both the briq and the ep405pc is the lack of board-level documentation. This makes adding support painstakingly slow at best.
I will be satisfied having the code back to the point where at least development can continue.
Greg
-
ebiederman＠lnxi.com -
Greg Watson