Re: Can't allocate resources for PCI video card behind bridge

["Rafael J. Wysocki" <rjw@sisk.pl>]

Cc-ing linux-pci and Jesse.

On Thursday 08 January 2009, Connor Behan wrote:
> Hello, I am trying to use two video cards. One is the built in ATI Rage 
> Mobility M3 AGP card which drives the screen of my laptop (Thinkpad a22m 
> 2628-S1U if that matters), the other is the ATI Radeon X1550 PCI card in 
> the Thinkpad Dock II which is supposed to drive an external monitor. 
> X1550 is a PCI-E chipset but my card is a PCI card with an onboard PCI 
> to PCI-E bridge. I first tried this with kernel 2.6.27 as packaged by 
> Archlinux and got the following startup errors:
> 
> pci 0000:00:04.0: BAR 7: can't allocate resource
> pci 0000:00:04.0: BAR 8: can't allocate resource
> pci 0000:00:04.0: BAR 9: can't allocate resource
> 
> I've seen this problem discussed in the archives and couldn't find what 
> looked like a fix. I WAS able to fix this by loading dock, pci_slot, 
> pci_hotplug and acpiphp and appending pci=assign-busses. However since 
> then I have run a package update to kernel 2.6.27.10 and I am once again 
> getting the same problem even with the same modules and parameters. I 
> have since tried appending irqpoll, pci=bios, pci=routeirq and acpi=off 
> with no success. I have even rolled back my kernel to 2.6.27 (and the 
> headers and a few other packages) setup my system the way it was setup 
> before to the best of my knowledge but I still can't get the PCI card 
> working again. Another subtle change must be responsible.
> 
> Certain PCI devices in the dock are working such as the Cardbus slots... 
> but I could care less about them... is there a way I could tell the 
> kernel to prioritize the video card and sacrifice Cardbus slots first if 
> it can't allocate enough resources? Also my lspci output shows a large 
> gap 01:00.0 to 06:00.0 so some part of my system must have expected 
> other devices in that range. When I had the video card working it was 
> 02:00.0. I have tried changing the four IRQ numbers in the BIOS but this 
> is pointless at best and sometimes causes my soundcard to be disabled. 
> My dmesg, lspci and (trimmed) kernel config are pasted:
> 
> dmesg: http://pastebin.com/f3ae15a58
> lspci: http://pastebin.com/f5d7dee6e
> .config: http://pastebin.com/fb925760
> 
> I'm hoping for a solution that doesn't require recompiling the kernel 
> but I definitely would if that's necessary. In any event I'll be much 
> more vigilant about system updates if I get this working again. 
> Thank-you very much for your time.