[moved] die layout of the Northbridge core logic chipset on pc motherboards

[Victor43]

My apologies to everyone if this is the incorrect group for this topic. I was not sure whether it falls under digital signals or analog. I'm not an engineer not have any background in EE.

Could anyone familiar with the design of the die or of this IC belonging to any older model AMD or Intel or other Northbridge chipset ? This chipset (IC) is found on computer motherboards.

1. Does the NB chip have a processor core or simply a core (logic) ?
2. If the NB chip does have a core would it be just one single core (logic) or multiple cores (logic) ?
3. If the NB does have an embedded core (logic) on die is it loaded by a boot loader ?
4. If NB does have a boot loader where on the NB die would the boot loader be found ? Would it be found somewhere in the flash memory or in EEPROM or ROM on the NB die ?

Thanks

 

[ads-ee]

1. I don't know the actual details of what the designs look like inside, but given the northbride is basically a bridge design from the FSB to the memory controller, PCI, and southbridge, would likely mean it's all logic as performance is paramount.

2. Likely multiple modules for various functional blocks (like any good design) e.g. PCI interface, southbridge interface, DMA engines, FSB interface, etc.

3. you mean embedded processor...and embedded core (logic) is what is in all chip designs. see 1, I doubt there is any boot loader as there is unlikely to be any kind of processor (i.e. slow) being used just logic, FSMs, and configuration registers.

4. No where see 1 and 3.

 

[Victor43]

Hello ads-ee.

Thanks very much for the above response. We have been searching Google for a while now just to confirm that the Northbridge chipset IC also contains an embedded core.

May we ask yourself including anyone else some further questions ?

Yes exactly we have discovered that a typical MCU and SoC and CPU all have en embedded (logic) core. We were not sure of the Northbridge chipset IC found in desktop and laptop motherboards. If the NB IC does have a core would it be just one single core (logic) or multiple cores (logic) ? Where on the die of this IC would you find this logic core on the topmost layer ? Please correct me if I'm wrong but the embedded core is sort like an embedded OS for the chip that controls all functions (IO) of the IC ? So in the case of the NB IC the (logic) core controls manages all communications with the CPU/GPU (via FSB) and ALL communications with the Southbridge chipset IC (via Internal Bus) ?

WE have discovered that a typical MCU (single layer or multi layered) and SoC have a boot loader which loads the bootstrap embedded core. Could you or anyone else tell us for either of these implementations (MCU/SoC) where there are multi cores does each embedded core require its own dedicated boot loader ? If the answer is yes then can the boot loader for either of these two IC's reside anywhere on the die other then in flash memory or in EEPROM or ROM ? Lastly again using a multi embedded core MCU or SoC IC's as an example how does the boot loader know where to locate the core in the case of multi embedded cores chips ?

Thanks again

 

[ads-ee]

You seem to be fixated on the die having to have some sort of SoC or mulit-processor of some kind in it. Why?

Back when NB chips were popular circa 2000, the only parallel processing done anywhere was done on Cray super computers. Those old PCs didn't have any parallel processing, the CPUs themselves were almost all single threaded. Your mixing new generation hardware where SoCs and multi-processor designs are common place and old technology where there was no such thing as SoCs and multiprocessing.

Speed and throughput are the overriding requirements of a bridge. Using a processor on any datapath function and not purely a a maintenance function will mean worse performance. Hence my previous explanation, the design of the Northbridge is likely pure logic and hardware FSMs along with a bunch of configuration registers. Looking at a user guide or the datasheet should give an idea if there is any kind of microcontroller embedded in the design (which I highly doubt).

A lot of modern processors now have the NB logic on the same die to improve performance as going off chip to a separate NB chip will be far slower. Given they increase in the number of transistors on a die it's no longer a problem to incorporate the NB functions on the processor die. But once again this returns the the fact that SoC and multiprocessor designs didn't really appear commercially until around '05. The cell processor in the PS3 was an example of such a product (only 10 years ago).

Your questions aren't really suited for being answered on this type of forum. Many of your questions are fundamental to computer architecture, which you've pretty much stated you have no formal knowledge of and have no engineering background. You should probably take classes at your local university or invest in book(s) on the subject.

 

[Victor43]

Thanks ads-ee. I'll respond to your last post shortly. I will provide the answers you have asked.

 

[Victor43]

Thanks ads-ee. I'll respond to your last post shortly. I will provide the answers you have asked.

Ads-ee yes I am interested in the design layout of the embedded cores found on SoC and MCU from a reversing point of view (that is finding its location on die) and also the same interest in the NB IC. Thanks for the tip about reading up on the datasheet on the NB. I'll do just that. Would you suggest from which forum or source I could get answers for the core and boot loader questions ? There is a personal project which I have been working on with a focus on multi core IC's which includes a MCU and SoC. Hope this helps answer any questions of why the interest on these IC's.

 

[ads-ee]

Ads-ee yes I am interested in the design layout of the embedded cores found on SoC and MCU from a reversing point of view (that is finding its location on die) and also the same interest in the NB IC. Thanks for the tip about reading up on the datasheet on the NB. I'll do just that. Would you suggest from which forum or source I could get answers for the core and boot loader questions ? There is a personal project which I have been working on with a focus on multi core IC's which includes a MCU and SoC. Hope this helps answer any questions of why the interest on these IC's.

Actually it doesn't matter why you are interested in the architecture of a NB IC, and I never asked you if you were interested in the layout of SoCs and MCUs. The point I've been making is that the NB isn't designed to run software (which is all a bootloader is). It's a hardware bridge device to connect bus A to bus B.

As to the location of features on a die for SoCs and MCUs that is something that is normally not divulged by the IC vendors. So good luck finding any information on that. Some features are pretty easy to determine just by the way they look to the naked eye on a bare die. Things like SRAM on a die is usually pretty obvious. I'm wondering why you need to know any of this...it seems somewhat suspect like trying to reverse engineer someones IP.

Bootloaders are just software so they can reside on die or off die, depending on whether or not there is any non-volatile memory on the die or not.

 

[Victor43]

Actually it doesn't matter why you are interested in the architecture of a NB IC, and I never asked you if you were interested in the layout of SoCs and MCUs. The point I've been making is that the NB isn't designed to run software (which is all a bootloader is). It's a hardware bridge device to connect bus A to bus B.

As to the location of features on a die for SoCs and MCUs that is something that is normally not divulged by the IC vendors. So good luck finding any information on that. Some features are pretty easy to determine just by the way they look to the naked eye on a bare die. Things like SRAM on a die is usually pretty obvious. I'm wondering why you need to know any of this...it seems somewhat suspect like trying to reverse engineer someones IP.

Bootloaders are just software so they can reside on die or off die, depending on whether or not there is any non-volatile memory on the die or not.

Thank you very much ads-ee for the helpful reply. Can you please share whether flash memory or EEPROM or another kind of ROM on die would be as easy to locate as what you have described for SRAM ? Thank you.

The interest in the such details does not have anything to do with reversing to learn or steal IP or anything along these lines but actually there is a honest initiative. I would rather not share the reasons on a open forums board. But if you would like PM myself I would be happy to share some of the details. If PM rules allows myself to forward an email address I would be happy to share all details.