[coreboot] here's a good one

Tom Sylla tsylla at gmail.com
Sat May 10 14:39:08 CEST 2008

ron minnich wrote:
> The via USB card looks like this:
>         Interrupt: pin A routed to IRQ 11
>         Interrupt: pin B routed to IRQ 9
>         Interrupt: pin C routed to IRQ 11
> so it's using IRQ 9 and 11, depending on port.
> The port I plugged the usb into was UHCI.
> But we had a problem with MFGPT not working due to improper IRQ
> controller setup. Is there any chance of a PCI conflict with the
> onboard USB controller?

For *all* of these IRQ issues, you need to follow the path of the IRQ to 
debug it. Dump out the registers along the way, and see what is set 
right, and what is set wrong.

INTs A, B, and C, are GPIOs on 5536. Check the register settings for 
those 3 bits. Are they set right? Those GPIOs get mapped to interrupts 
in the interrupt mappers. Are they set right? Are 4d0/4d1 set right?

There are only about 4 registers that control how the interrupts move, 
and they need to be checked before anything else. (I would do it, but I 
have no alix)

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