Re: pq2_find_bridges hangs system

Alex BASTOS wrote:

Vitaly,

So, I have arrived to some conclusions.

1) With my previous kernel version (2.6.11) I had no problems
because it had CONFIG_PCI_8260 and CONFIG_PPC_INDIRECT_PCI unset.
So I think no effective read/write operation was executed, and so
that, no Machine Check.

In fact, this is the configuration I would prefer for my board. I have
to set CONFIG_PCI for enabling USB, but I don't want all the HW stuff
of the PCI. I can get these also with 2.6.15 if I modify Kconfig, to
allow me to unset PCI_8260 (and then PPC_INDIRECT_PCI) for my board.
With that, the problem dissapears and I can boot 2.6.15.

Shouldn't this (PCI_8260) be visible from xconfig for those like me
who wants USB (=> CONFIG_PCI) but don't really have any PCI device?

Maybe, but I guess more correct is to deal with USB->PCI dependency.. Is it really needed(I am not USB expert)?

2) Although I am using Uboot 1.1.4, it is not top of git. I have
found your changes to support PCI on 8272ADS for u-boot are not
still applied on the version i am using. So, could this be causing
the problem? Is there any configuration done in u-boot required by
the PCI on the linux kernel to boot (BR3,OR3, EMR, ...)?

I should say that, on ADS, I have an older version of u-boot, 1.1.2,
and it boots OK.

My changes do not required for kernel to deal with PCI, that patch just allows access to PCI in U-Boot. Hence I might be useful if you'll head for resolving this issue which I guess unlikely to happen

3) I have seen that from u-boot, a reset occurs when I read Internal
Memory at offset 0x10904 (PCI CFG_DATA). From BDI, when I do the same
all PCI section on IM becomes zero. Is this a known behaviour? May this
reflect a hardware problem?

Sounds weird

In conclusion, 1) solves my "must", a working board (without PCI).
But I still would like to know what am I doing so wrong with this.

IMHO ability to disable PCI_8260 while PCI is on might be confusing, at least for upstream.

Best regards,

Alex

Citando Alex BASTOS [off-list ref]:

quoted

Vitaly,

It didn't work. So I will check pq2ads_setup_pci to check if
some board specific issue is affected.

I will say you if I find anything

Thanks

Alex.

-- 
Sincerely, Vitaly