6.9.0 drivers no longer handle multiple cards?

[vdb128 at picaros.org]

I can confirm the same behaviour on an intel d955xbk motherboard
using a radeon x300 and 9250.  The BIOS doesn't route INTA of the secondary
card and leaves it in a disabled state.  Booting with the x300 gives

01:00.0 VGA compatible controller: ATI Technologies Inc RV370 5B60 [Radeon X300 (PCIE)] (prog-if 00 [VGA])
        Interrupt: pin A routed to IRQ 11
        Region 0: Memory at 80000000 (32-bit, prefetchable) [size=128M]
        Region 1: I/O ports at 3000 [size=256]
        Region 2: Memory at 98210000 (32-bit, non-prefetchable) [size=64K]
        Expansion ROM at 98220000 [disabled] [size=128K]

05:01.0 VGA compatible controller: ATI Technologies Inc RV280 [Radeon 9200 PRO] (rev 01) (prog-if 00 [VGA])
        Interrupt: pin A routed to IRQ 0
        Region 0: Memory at 90000000 (32-bit, prefetchable) [disabled] [size=128M]
        Region 1: I/O ports at 1100 [disabled] [size=256]
        Region 2: Memory at 98010000 (32-bit, non-prefetchable) [disabled] [size=64K]
        Expansion ROM at fffe0000 [disabled] [size=128K]

This is lspci output when X is running.  Directly after boot it gives

01:00.0 VGA compatible controller: ATI Technologies Inc RV370 5B60 [Radeon X300 (PCIE)] (prog-if 00 [VGA])
        ...
        Expansion ROM at a0000000 [disabled] [size=128K]
                         ^^^^^^^^

Trying X on the secondary 9250 fails with the log

(WW) ****INVALID IO ALLOCATION**** b: 0x1100 e: 0x11ff correcting
(EE) RADEON(0): Cannot read V_BIOS

Enabling this card through bootparam 'pci=routeirq' and 
'setpci -s 05:01.0 command=7' gives 

(II) Module int10: vendor="X.Org Foundation"
        compiled for 6.9.0, module version = 1.0.0
        ABI class: X.Org Video Driver, version 0.8
(II) RADEON(0): initializing int10
(II) Truncating PCI BIOS Length to 53248

just before the computer hangs. 

However, booting with the 9250 as primary using 'pci=routeirq' and issuing 
a 'setpci -s 01:00.0 command=7' does allow to start 'X -probeonly' on the 
x300.  The monitor synchronizes to the correct modeline but the computer 
hangs.  

Perhaps pci_enable_device() doesn't do what the ATI/radeon driver expects ?

The logfiles are at http://picaros.org/xorg/.
S.V.