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Subject: Re: Beginning SPARC port 
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On Sat, 13 Dec 1997 21:51:10 -0800 Amancio Hasty
<hasty@rah.star-gate.com> writes:
>The functions is already there:
>
>        old_irq = pci_conf_read(tag, PCI_INTERRUPT_REG);
>        pci_conf_write(tag, PCI_INTERRUPT_REG, BROOKTREE_IRQ);
>
>And usually PCI devices have i/o mapped registers.

On the i386, this is true, but (as has been said before, but I guess not
as clearly) there are architectures out there that don't have an
Intel-style I/O vs. memory addressing distinction (the 680x0s are like
this, and I think the SPARC and PowerPC are also; not sure about Alpha),
so they map all the device registers into physical memory space.