Nekochan Net

just curious, if so, how did linux and bsd porting to sgi done? does it mean they didn't utilize these chips and all relied on main CPU? that's why its slow compared to IRIX? if not, how did they reversed engineer a specific chip? sorry for noob but is it possible to read the contents of an ASIC and copy it?

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(Sakura) (Sasuke) (Naruto) ... lil Jesse! (O2 laptop)
“Imagination is more important than knowledge.“ – A. Einstein

There is no choice but to use these chips. For example, in order to be able to use the SCSI controller, you need to be able to talk to the PCI Bridge it lies beneath. But in this particular example, the SGI XBow-PCI Bridge has specific features to do some sort of dynamic bandwidth shaping for the DMA operations, as well as the ability to use virtual adresses for DMA (in other words, scatter-gather for transfers spanning multiple pages), and these are not supported by BSD or Linux because the scarce information available about this chip does not cover these well enough.


The main source of information are the IRIX system header files. SGI also contributed some code to Linux to support the Altix systems, which acts as an unsorted source of tidbits and quirks about these chips (many hardware defects and their workarounds are mentioned in these contributions).

Another source of information is the patents SGI filed about some of its chips. They don't dive into the details, but give a good overview of what the chips are capable of.

Several comments in the Linux Octane-specific files hint that there was some disassembly involved, at least for the Impact support. I also believe that the GR2 ``texport'' IRIX routines were disassembled by NetBSD developrs, which led to the initial XZ support in NetBSD


Not really. You may be able to copy an FPGA, assuming there is a debug probe connector left on the board (assuming you recognize the FPGA flavour and have the proper tools for it), but ASIC are out of reach of mere mortals.

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R4000 R4400 R4400 R8000 R10000 R4000PC R4000SC R5000SC R5000 RM7000 2xR10000 R12000 - 2x2xR10000 R16000
among more than 150 machines : Apollo, Be, Data General, Digital, HP, IBM, MIPS before SGI, Motorola, NeXT, SGI, Solbourne, Sun...

hi miod! really thanks for this reply, really answers most of my questions that can affect some of my future project with my SGIs


yeah, also thought so, looking at the block diagrams from Ian for both O2 and Octane, there's no possible way without utilizing these chips, sorry for still asking tho, just want to confirm hmm so that's why porters for BSD and Linux still saying that some chips are xx% in progress, and this is why these OS are slower than the IRIX.


ah i see, geeez i can imagine the porters, really need patience on gathering these infos.. but its worth especially after able to successfully boot these OS hehe i really salute to them. i just hope that maybe some old IRIX engineers still have some documents left and can share it here


ah i see, geez all SGI chips use ASIC right? hahaha mere mortals, like this one

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(Sakura) (Sasuke) (Naruto) ... lil Jesse! (O2 laptop)
“Imagination is more important than knowledge.“ – A. Einstein

some more interesting reverse engineering techniques with a focus on smartcards: http://www.cl.cam.ac.uk/~mgk25/sc99-tamper.pdf

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(Maradona) (DavidVilla) A1186 (Xavi)
A1370 (Messi) dp43tf (Puyol) A1387 (Abidal) A1408 (Guardiola)

"InfiniteReality Graphics - Power Through Complexity"

when you see photomicrographs of chips, like these, they have usually been made by removing the package around the chip. For typical plastic or epoxy potted chips strong acids are used: see this page. I don't know what they do for metal encapsulated chips.

With detailed enough photos of the chip its internal structure can usually be discerned, since they are composed of standard pieces called "macrocells". However, tracing all the connections between the cells is very time consuming, especially with multiple layers of metal interconnect. It is possible to polish away the layers one by one until reaching the silicon. The silicon itself has features that do not photograph easily, like ion implanted regions, vertical gate structures, etc.

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hey hey! once a bearcat always a bearcat! http://micro.magnet.fsu.edu/creatures/p ... rcats.html

https://www.facebook.com/photo.php?fbid ... d46ee41be3

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(Maradona) (DavidVilla) A1186 (Xavi)
A1370 (Messi) dp43tf (Puyol) A1387 (Abidal) A1408 (Guardiola)

"InfiniteReality Graphics - Power Through Complexity"

Yeah, but most of those guys now work for the card and security companies, improving cards to prevent that type of thing. So hacking official smartcards nowadays is really beyond the realm of a hobbyist.

Actually what happens nowadays is that the best hackers from back then who didn't go working for the major card companies are now hired by organised crime gangs. They thus have the resources to buy code & docs on the black market for the card and card vendor they are targeting (and they are well funded - the going rate was typically 150-300k a couple of years ago). To try and protect their investment, these commercial hackers now use secure smartcards themselves when implementing their own "products". Hobbyists do have a chance of hacking these, because they typically don't follow rigorous or formal engineering principles like a proper security company would.

Alas, the technology in ageing UNIX workstations hasn't quite the same appeal to commercial hackers, so any leak would really have to be voluntary.

Is it March yet ? Just for fun called them back today. Miss Wang said, "Oh sorry we don't have that now, call back in a few days later maybe we will have."

Right. If these people had a hot dog stand they'd run out of hot dogs. In fact the KFC down the street from me runs out of chicken several times a week. And last time I was stupid enough to stop by Mickey D they were out of almost everything.

And they're kickin' your butts. What's that say for American Businessmen ? hrrr hrrr hrr, what a bunch of brainless dorks.

There is a justification for this, depending on what's important to the business owner.

Running out of things represents a potential loss. You might have made more sales and might have brought in more money.

Having extra stuff left over is an actual loss. You've already spent the money, and it's being chucked into the garbage can right in front of your face.

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Damn the torpedoes, full speed ahead!

Systems available for remote access on request.

(single-CM)

Are you kidding ? here is China. You think they would throw something out just because it's two weeks old ?

hahahaha.. indeed

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(Sakura) (Sasuke) (Naruto) ... lil Jesse! (O2 laptop)
“Imagination is more important than knowledge.“ – A. Einstein

Isn't it a supply chain problem rather than a poor business planning problem? I mean, KFC and MacD franchisees have to buy through the corporate food chain, and according to everything I've heard the economic slowdown in China has hit the shipping and receiving centers the hardest, so, to paraphrase Carl Spackler, they've probably got a lot of stuff on order...

is it big or little endian?

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it's fast food, not real chicken. you can leave it for years without any effect.

_________________
(Maradona) (DavidVilla) A1186 (Xavi)
A1370 (Messi) dp43tf (Puyol) A1387 (Abidal) A1408 (Guardiola)

"InfiniteReality Graphics - Power Through Complexity"