re: BIOS POST, nested bridges and PhoenixBIOS

[<frances_cohen@phoenix.com> (Frances Cohen)]

Stephen,
  The 4.04 BIOS is quite old, and was the first version with bridge 
support.  Although it was tested with nested DEC bridges, there may be some 
issue that will specifically apply to the i960rp.  If it is your device you 
are testing in this configuration, I suggest using a 4.05 (or higher) BIOS. 

Frances Cohen
Phoenix Technologies
frances_cohen@ptltd.com
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Original Text
From Stephen Williams <steve@icarus.icarus.com>, on 3/24/97 3:16 PM:
To: SMTP@PTLNORWOOD3@Servers["Mailing List Recipients" 
<pci-sig-request@znyx.com>]

I have a situation where there are two bridges between the main PCI
bus and my device. bus 0 is the primary, bus 1 is the secondary, and
bus 2 is where the device lives. The first bridge is an i960RP and
the second is a DEC 21152. These devices work fine. O/S is Linux 2.0.

After boot, it appears that the PhoenixBIOS 4.04 BIOS locates all
the busses and bridges, but not my device. It properly locates the
DEC bridge, and configures it with correct windows for the device on that
bus. However, bus 1 has only the DEC bridge (which is properly configured).

The bridge portion of the i960rp bridge (which connects bus 0 to bus 1)
is not configured for any window at all. The DEC bridge underneath it
has the correct ranges, but the i960RP has none.

Furthermore, calls to the BIOS to locate the device turn up nothing,
and in the end Linux reports the device on bus 2 as not there.

The only evidence I have that the device was ever probed is the 
configuration
of the DEC bridge, which is correct for the device at hand.

Have I tripped on a bug in the Phoenix BIOS? Am I missing something?

-- 
Steve Williams
steve@icarus.com
steve@picturel.com

"The woods are lovely, dark and deep.  But I have promises to keep,
And lines to code before I sleep, And lines to code before I sleep."


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ô¨–