Re: [PATCH] Register PCI host bridge resource earlier

[Sergei Shtylyov <sshtylyov@ru.mvista.com>]

Hello.

Thomas Bogendoerfer wrote:

>>>PCI based SNI RM machines have their EISA bus behind an Intel PCI/EISA
>>>bridge. So the PCI IO range must start at 0x0000. Changing that will
>>>break the PCI bus, because i8259.c already has registered it's IO
>>>addresses before the PCI bus gets initialized. Below is a patch,
>>>which will register the PCI host bridge resources inside
>>>register_pci_controller(). It also changes i8259.c to use insert_region(),
>>>because request_resource() will fail, if the IO space of the PIT hanging
>>>of the PCI host bridge (maybe passing the resource parent to
>>>init_i8259_irqs() is a cleaner fix for that).

>>   First, I don't understand how PIT and PIC resources may intersect. Then, 

> oops, I meant PIC resources.

>>IIUC, using inert_resource() will cause PIT resource be the child of the 
>>PIC resource which doesn't make sense either.

> the insert_resource will make it child of the PCI resource, which makes
> perfect sense, because the ISA bus is behind the PCI host bridge.

    If you read the comment to insert_resource() you'll see that it works 
contrarywise, i. e. the inserted resource is made parent of the conflicting 
ones. I.e. it should't work as you're intending it to.

> Thomas.

WBR, Sergei