[coreboot] proposed patch, notsigned off, comments welcome.

Tom Sylla tsylla at gmail.com
Mon May 12 15:59:57 CEST 2008

On Mon, May 12, 2008 at 12:51 AM, ron minnich <rminnich at gmail.com> wrote:
>  I don't actually see a difference from my end between an IRQ
>  (Interrupt request in old-speak) and a PCI INT (interrupt request in
>  old speak) but if you want to rename things, have at it. Code
>  attached, do your worst!

This tool is a bit useful already. Can you run it on the alix1c's
tinybios (or whatever works best on the alix)? Do all ports of your
USB card work on alix with that BIOS? At a minumum, you need to check
and make sure that INTs A-D are *really* GPIOs 0, 7, 12, and 13. (and
as Peter said, you need to verify how they are hooked up to the slot)

I think Peter gets it, but the last piece missing from the tool is how
the GPIOs (INTs) get mapped to the interrupts (IRQs). There are 2
pieces of this, the GPIO mappers and the IRQ mappers. The GPIO mapper
selects which of the 7 interrupt outputs from the GPIO block are
mapped to a specific GPIO pin. The registers are in GPIO space,
offsets EO, E4, and E8. After that, those 7 outputs from the GPIO
block can be mapped onto a particular IRQ number. That happens in the
IRQ mapper register, which is MSR address 51400023 for the GPIO

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