pci issue - wrong detection of pci ressources

[Christian Ehrhardt]

Benjamin Herrenschmidt wrote:
>> Yes you're right. Early at the pci initialization are errors of the allocation for pi ressources.
>> And that are exactly the ressources failing later, so that pci initialization seem to be the reason for my problem.
>> Was there any simple solution (e.g. just somehow increase memory reserved for pci) when you came across that issue Johan ?
> 
> Hrm... I was expecting to see a lot more output here, make sure you have
> "debug" on your command line (or enable early debug output, same
> effect).

There is nothing more even with debug in kernel command line.
But I added some printk's around the resource handling to get a better feeling what's happening.
I attached the new extended bootlog and the patch with the printk's for a better understanding where which message is printed.

I tried to understand how I might e.g. increase the number of available resources or their size, but unfortunately that is not the simplest code when working with it the first time ;-)

> Cheers,
> Ben.
> 
> 

For comparison I defined DEBUG in the good kernel (arch=ppc) and that is what the initialization prints (pci ...:0a:1 is the secondary head of the same graphic card an it's not an issue if thats not allocated):
good case:
PCI: Probing PCI hardware
PCI: bridge rsrc 0..ffff (100), parent c0354624
PCI: bridge rsrc 80000000..8fffffff (200), parent c0354608
PCI:0000:00:0a.0: Resource 0: 0000000088000000-000000008fffffff (f=1208)
PCI:0000:00:0a.0: Resource 1: 000000000000ff00-000000000000ffff (f=101)
PCI:0000:00:0a.0: Resource 2: 0000000087ff0000-0000000087ffffff (f=200)
PCI:0000:00:0a.1: Resource 0: 0000000078000000-000000007fffffff (f=1208)
PCI: Cannot allocate resource region 0 of device 0000:00:0a.1
PCI:0000:00:0a.1: Resource 1: 0000000077ff0000-0000000077ffffff (f=200)
PCI: Cannot allocate resource region 1 of device 0000:00:0a.1
PCI: Failed to allocate mem resource #0:8000000 at 90000000 for 0000:00:0a.1

-- 

Grüsse / regards, 
Christian Ehrhardt
IBM Linux Technology Center, Open Virtualization
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