[PATCH 2/8] Add uli1575 pci-bridge sector to MPC8641HPCN dts file.

Randy Vinson rvinson at mvista.com
Tue Jun 5 08:31:56 EST 2007


Andy Fleming wrote:
> On Jun 3, 2007, at 03:33, Gabriel Paubert wrote:
> 
[snippage]
>>
>> This said, I'm looking at device trees right now, and I can understand
>> that interrupt-parent of the 8259 is &mpic in mpc8641_hpcn.dts, but
>> I don't understand at all why it is &pci1 on the mpc85??cds.dts.
>>
>> But the definition of the ISA bridge in these files is very strange to
>> start with: I've never seen an ISA bridge with only an interrupt  
>> controller
>> on it, no interrupts are connected to it and its reg property is
>> almost certainly wrong. Maybe it is an example of things that should
>> not be done.
> 
> 
> I take full responsibility for that.  The CDS is a strange beast, so  
> I did some strange things in the DTS.
> 
> The i8259 is on a subsidiary bus, and so it's one bus #1.
Actually, that's not strictly true. If a card containing a P2P bridge is
installed into PCI slot 4, the i8259 will end up on a bus that is not
numbered bus 1. I've often wondered how something like that is handled
in the DTS.

Randy V.



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