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Re: Non-Host CPU/PCI Bridge
>
> Hi there !
>
> An annoucement and a Question :
>
> The question :
>
> Let's imagine I want to build a multiprocessor hardware,
> with off-the-shelf plug-in cards,
> around a PCI bus.
>
> The idea is to plug 3 [Processor + DRAM + CPU/PCI bridge]s on
> a standard motherboard. The processors could be Pentiums, PowerPCs
> or AXPAlphas. This should lead to quite a good perfomance/price
> ratio.
>
> The problem is, the CPU/PCI Bridge on the expansion cards cannot
> be a standard HOST/PCI bridge, for 2 reasons :
> 1/ It cannot receive configuration accesses,
> 2/ The DRAM is always wired to a fixed physical address.
>
> Is anyone aware of a CPU/PCI bridge, or of a Non-Host CPU plug-in
> card ?
For a possible PowerPC solution see "Designing a System with Multiple
Grackles on the same PCI Bus" on page 33 of:
http://www.mot.com/pub/SPS/PowerPC/support/hw_design/FAQ/apps_faq.pdf
This shows a way of getting around the DRAM addressing using
ISA_MASTER but it still cannot accept configuration accesses.
Regards,
Andrew Crosland
Principal Engineer
PowerPC Product Group
* email: crosland@radstone.co.uk Radstone Technology plc *
* Tel: +44 (0)1327 359444 Water Lane, Towcester *
* Fax: +44 (0)1327 358113 Northants, England NN12 6JN *
* Web: http://www.radstone.co.uk *
* http://www.radstone.com *
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´ ¡