Does this chip exist?

[Eric Goodill <ericg@cisco.com>]

Hi,

I'm new to PCI, so I don't really know what's out there in the
market nor who the main players are.  If you are familiar with
PCI bridge chips, I'd appreciate if you'd have a look at this.

I've got some chips that only have 33 MHz PCI ports.  Logically,
I want to connect all these chips to a single ASIC.  Due to
33 MHz PCI performance limitations, I cannot connect all these
chips onto a single 33 MHz PCI bus.

So far I've thought of breaking the chips into two groups each
of which is connected together via a 33 MHz PCI bus.

How, then, do I get this into the ASIC?

I'm looking at having two PCI-bus ports on the ASIC, but there
are some problems with that, so I'm looking at a way to do this
outside the ASIC.

Ideally, I could find one chip, Chip X, that has three ports:
(1) 33 MHz PCI bus, (2) 33 MHz PCI bus, and (3) some higher-speed
port (PCI or not) to connect to our ASIC.

This is shown below.

+---+ +---+ +---+
| A | | A | | A |
+---+ +---+ +---+   +----------+
  |     |     |     |          |
  +-----+-----+-----|          |  some bus    +------+
  2 x 33 MHz PCI    |  Chip X  |--------------| ASIC |
  +-----+-----+-----|          |  50 - 66 MHz +------+
  |     |     |     |          |
+---+ +---+ +---+   +----------+
| A | | A | | A |
+---+ +---+ +---+

Each of the chips of type A and the ASIC can initiate bus
transactions.

If Chip X doesn't exist, then I'm thinking of trying an FPGA.

If that doesn't work, I think I could do the following:

               +--------+
33 MHz PCI ----| Bridge |-- 66 MHz PCI --+
               +--------+                |  +------+
                                         +--| ASIC |
               +--------+                |  +------+
33 MHz PCI ----| Bridge |-- 66 MHz PCI --+
               +--------+

However, this is my least favorite solution.

If you don't of Chip X specifically, can you recommend some
vendors to take a look at?

-Eric
--
Eric Goodill, Hardware engineer
Cisco Systems, ericg@cisco.com