SONIC interrupt handling
Install the built-in macsonic interrupt handler on both IRQs when using
via_alt_mapping. Otherwise the rare interrupt that still comes from the
nubus slot will wedge the nubus.
$ cat /proc/interrupts
auto 2: 89176 via2
auto 3: 744367 sonic
auto 4: 0 scc
auto 6: 318363 via1
auto 7: 0 NMI
mac 9: 119413 framebuffer vbl
mac 10: 1971 ADB
mac 14: 198517 timer
mac 17: 89104 nubus
mac 19: 72 Mac ESP SCSI
mac 56: 629 sonic
mac 62:
1142593 ide0
Version 1 of this patch had a bug where a nubus sonic card would register
two interrupt handlers. Only a built-in sonic needs both.
Versions 2 and 3 needed some cleanups, as Raylynn Knight and Christoph
Hellwig pointed out (thanks).
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>