There are no slow IRQs on Macs since Roman Zippel's IRQ reorganisation that
went into 2.6.16 and removed mac_irq_list[] and the do_mac_irq_list()
dispatcher. (They were implemented in do_mac_irq_list() by lowering the IPL.)
Hence there's no more use for mutual exclusion in the Mac interrupt
dispatchers. Remove it.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Some Macs lack a slot interrupt enable register. So the existing code makes
disabled and unregistered slot IRQ lines outputs set high. This seems to work
on quadras, but does not work on genuine VIAs (perhaps the card still succeeds
in pulling the line low, or perhaps because this increases the settle time on
the port A input, meaning that the CA1 IRQ could fire before the slot line
reads active).
Because of this, the nubus_active flags were used to mask IRQs, which is
actually worse than the problem it tries to solve. Any interrupt masked by
nubus_active will remain asserted and prevent further transitions on CA1. And
so the nubus gets wedged regardless of hardware (emulated VIA ASIC, real VIA
chip or RBV).
The best solution to this hardware limitation of genuine VIAs is to disable the
umbrella SLOTS IRQ when disabling a slot on those machines. Unfortunately, this
means all slot IRQs get disabled when any slot IRQ is disabled. But it is only
a problem when there's more than 1 device using nubus interrupts.
Another potential problem for genuine VIAs is an unregistered nubus IRQ.
Eventually it will be possible to enable the CA1 interrupt by installing its
handler only _after_ all nubus drivers have loaded but _before_ the kernel
needs them, at which time this last problem can be fixed. For now it can be
worked around:
- disable MacOS extensions
- don't boot MacOS (use the Emile bootloader instead)
- get the bootloaders to disable ROM drivers (Penguin does this for video
cards already, don't know about Emile)
- physically remove unsupported cards
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make sure that there are no slot IRQs asserted before leaving the nubus
handler. If there are and we don't then the nubus gets wedged because this
prevents a CA1 transition, which means no more nubus IRQs.
Make the interrupt dispatch loops terminate sooner.
Explicitly initialise the VIA latches to make the code more easily understood.
Also some cleanups.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reverse the last of a monumental brown-paper-bag commit that went into the 2.3
kernel.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add some more machines that support A/UX interrupt priorities. There are
probably others as well, but I've only tested these ones so far.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use the new typedef for interrupt handler function pointers rather than
actually spelling out the full thing each time. This was scripted with the
following small shell script:
#!/bin/sh
egrep -nHrl -e 'irqreturn_t[ ]*[(][*]' $* |
while read i
do
echo $i
perl -pi -e 's/irqreturn_t\s*[(]\s*[*]\s*([_a-zA-Z0-9]*)\s*[)]\s*[(]\s*int\s*,\s*void\s*[*]\s*[)]/irq_handler_t \1/g' $i || exit $?
done
Signed-Off-By: David Howells <dhowells@redhat.com>
m68k_handle_int() split in two functions: __m68k_handle_int() takes
pt_regs * and does set_irq_regs(); m68k_handle_int() doesn't get pt_regs
*.
Places where we used to call m68k_handle_int() recursively with the same
pt_regs have simply lost the second argument, the rest is switched to
__m68k_handle_int().
The rest of patch is just dropping pt_regs * where needed.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Some fixes and cleanups from the linux-mac68k repo. Fix mac_esp by clearing
the VIA2 SCSI IRQ flag before the SCSI IRQ handler is invoked. Also fix a
race condition caused by unmasking a nubus slot IRQ then setting the relevant
nubus_active bit.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Finn Thain