Subject: Re: Interrupt interaction with OFW properties.
To: Jochen Kunz <>
From: Bill Studenmund <>
List: port-ofppc
Date: 06/03/2003 14:40:38
On Tue, 3 Jun 2003, Jochen Kunz wrote:

> The code from macppc queries for the property "AAPL,interrupts". Is this
> somthing special to macppc? The OFW on the PowerStack II has the
> property "interrupts" and the OFW-PCI binding talks about "interrupts"
> too. Or is there some special semantic behind the ","?

"AAPL," means it's an Apple thing. "AAPL,interrupts" is a property that
lists the interrupt pin on many Apple models.

> The OFW "interrupts" property is allways 1 for all PCI devices, so the
> PCI attach code gets "IRQ 1" for all PCI devices. If I don't use the
> find_node_intr() function and leave PCI_INTERRUPT_REG untouched, the
> devices get the correct interrupt. (I know the interrupt routing of that
> machine from the Linux source linux/arch/ppc/kernel/prep_pci.c,
> Utah_pci_IRQ_map[] and Utah_pci_IRQ_routes[]). So it looks to me like
> the OFW initializes the PCI_INTERRUPT_REG correct, but doesn't supply a
> correct "interrupts" property. Correct? Or is there somthing else I
> don't know already.

Sounds like the OFW settings aren't set up right, or they are instead
indicating if a device has an interrupt, not what line it's on.

Take care,