Only pil0_dummy_bucket had a pil of zero and we just killed that
off, so we can delete all special case code that used bp->pil==0
as a way to identify a dummy bucket.
Signed-off-by: David S. Miller <davem@davemloft.net>

This is the first in a series of cleanups that will hopefully
allow a seamless attempt at using the generic IRQ handling
infrastructure in the Linux kernel.

Define PIL_DEVICE_IRQ and vector all device interrupts through
there.

Get rid of the ugly pil0_dummy_{bucket,desc}, instead vector
the timer interrupt directly to a specific handler since the
timer interrupt is the only event that will be signaled on
PIL 14.

The irq_worklist is now in the per-cpu trap_block[].
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

When we stop allocating percpu memory for not-possible CPUs we must not touch
the percpu data for not-possible CPUs at all.  The correct way of doing this
is to test cpu_possible() or to use for_each_cpu().

This patch is a kernel-wide sweep of all instances of NR_CPUS.  I found very
few instances of this bug, if any.  But the patch converts lots of open-coded
test to use the preferred helper macros.

Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Acked-by: Kyle McMartin <kyle@parisc-linux.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Christian Zankel <chris@zankel.net>
Cc: Philippe Elie <phil.el@wanadoo.fr>
Cc: Nathan Scott <nathans@sgi.com>
Cc: Jens Axboe <axboe@suse.de>
Cc: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

this patch converts arch/sparc64 to kzalloc usage.
Crosscompile tested with allyesconfig.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

We need to use the real hardware processor ID when
targetting interrupts, not the "define to 0" thing
the uniprocessor build gives us.

Also, fill in the Node-ID and Agent-ID fields properly
on sun4u/Safari.
Signed-off-by: David S. Miller <davem@davemloft.net>

The sibling cpu bringup is extremely fragile.  We can only
perform the most basic calls until we take over the trap
table from the firmware/hypervisor on the new cpu.

This means no accesses to %g4, %g5, %g6 since those can't be
TLB translated without our trap handlers.

In order to achieve this:

1) Change sun4v_init_mondo_queues() so that it can operate in
   several modes.

   It can allocate the queues, or install them in the current
   processor, or both.

   The boot cpu does both in it's call early on.

   Later, the boot cpu allocates the sibling cpu queue, starts
   the sibling cpu, then the sibling cpu loads them in.

2) init_cur_cpu_trap() is changed to take the current_thread_info()
   as an argument instead of reading %g6 directly on the current
   cpu.

3) Create a trampoline stack for the sibling cpus.  We do our basic
   kernel calls using this stack, which is locked into the kernel
   image, then go to our proper thread stack after taking over the
   trap table.

4) While we are in this delicate startup state, we put 0xdeadbeef
   into %g4/%g5/%g6 in order to catch accidental accesses.

5) On the final prom_set_trap_table*() call, we put &init_thread_union
   into %g6.  This is a hack to make prom_world(0) work.  All that
   wants to do is restore the %asi register using
   get_thread_current_ds().

Longer term we should just do the OBP calls to set the trap table by
hand just like we do for everything else.  This would avoid that silly
prom_world(0) issue, then we can remove the init_thread_union hack.
Signed-off-by: David S. Miller <davem@davemloft.net>

We'll lose events that way.
Signed-off-by: David S. Miller <davem@davemloft.net>

So that free_irq() disable's the IRQ correctly.
Signed-off-by: David S. Miller <davem@davemloft.net>

Call it from register_one_mondo().
Signed-off-by: David S. Miller <davem@davemloft.net>

On SUN4V, force IRQ state to idle in enable_irq().  However,
I'm still not sure this is %100 correct.

Call add_interrupt_randomness() on SUN4V too.
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: David S. Miller <davem@davemloft.net>

It just clutters up the log.
Signed-off-by: David S. Miller <davem@davemloft.net>

And check for errors at call sites.
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: David S. Miller <davem@davemloft.net>

Need to use hypervisor calls instead of direct register
accesses.
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: David S. Miller <davem@davemloft.net>

We have to use bootmem during init_IRQ and page alloc
for sibling cpu calls.

Also, fix incorrect hypervisor call return value
checks in the hypervisor SMP cpu mondo send code.
Signed-off-by: David S. Miller <davem@davemloft.net>

Function goes in %o5, args go in %o0 --> %o5.
Signed-off-by: David S. Miller <davem@davemloft.net>

We look for "SUNW,sun4v" in the 'compatible' property
of the root OBP device tree node.

Protect every %ver register access, to make sure it is
not touched on sun4v, as %ver is hyperprivileged there.

Lock kernel TLB entries using hypervisor calls instead of
calls into OBP.
Signed-off-by: David S. Miller <davem@davemloft.net>

Technically the hypervisor call supports sending in a list
of all cpus to get the cross-call, but I only pass in one
cpu at a time for now.

The multi-cpu support is there, just ifdef'd out so it's easy to
enable or delete it later.
Signed-off-by: David S. Miller <davem@davemloft.net>

Sun4v has 4 interrupt queues: cpu, device, resumable errors,
and non-resumable errors.  A set of head/tail offset pointers
help maintain a work queue in physical memory.  The entries
are 64-bytes in size.

Each queue is allocated then registered with the hypervisor
as we bring cpus up.

The two error queues each get a kernel side buffer that we
use to quickly empty the main interrupt queue before we
call up to C code to log the event and possibly take evasive
action.
Signed-off-by: David S. Miller <davem@davemloft.net>

Needs to occur before we enable PSTATE_IE in %pstate.
Signed-off-by: David S. Miller <davem@davemloft.net>

On uniprocessor, it's always zero for optimize that.

On SMP, the jmpl to the stub kills the return address stack in the cpu
branch prediction logic, so expand the code sequence inline and use a
code patching section to fix things up.  This also always better and
explicit register selection, which will be taken advantage of in a
future changeset.

The hard_smp_processor_id() function is big, so do not inline it.

Fix up tests for Jalapeno to also test for Serrano chips too.  These
tests want "jbus Ultra-IIIi" cases to match, so that is what we should
test for.
Signed-off-by: David S. Miller <davem@davemloft.net>

UltraSPARC has special sets of global registers which are switched to
for certain trap types.  There is one set for MMU related traps, one
set of Interrupt Vector processing, and another set (called the
Alternate globals) for all other trap types.

For what seems like forever we've hard coded the values in some of
these trap registers.  Some examples include:

1) Interrupt Vector global %g6 holds current processors interrupt
   work struct where received interrupts are managed for IRQ handler
   dispatch.

2) MMU global %g7 holds the base of the page tables of the currently
   active address space.

3) Alternate global %g6 held the current_thread_info() value.

Such hardcoding has resulted in some serious issues in many areas.
There are some code sequences where having another register available
would help clean up the implementation.  Taking traps such as
cross-calls from the OBP firmware requires some trick code sequences
wherein we have to save away and restore all of the special sets of
global registers when we enter/exit OBP.

We were also using the IMMU TSB register on SMP to hold the per-cpu
area base address, which doesn't work any longer now that we actually
use the TSB facility of the cpu.

The implementation is pretty straight forward.  One tricky bit is
getting the current processor ID as that is different on different cpu
variants.  We use a stub with a fancy calling convention which we
patch at boot time.  The calling convention is that the stub is
branched to and the (PC - 4) to return to is in register %g1.  The cpu
number is left in %g6.  This stub can be invoked by using the
__GET_CPUID macro.

We use an array of per-cpu trap state to store the current thread and
physical address of the current address space's page tables.  The
TRAP_LOAD_THREAD_REG loads %g6 with the current thread from this
table, it uses __GET_CPUID and also clobbers %g1.

TRAP_LOAD_IRQ_WORK is used by the interrupt vector processing to load
the current processor's IRQ software state into %g6.  It also uses
__GET_CPUID and clobbers %g1.

Finally, TRAP_LOAD_PGD_PHYS loads the physical address base of the
current address space's page tables into %g7, it clobbers %g1 and uses
__GET_CPUID.

Many refinements are possible, as well as some tuning, with this stuff
in place.
Signed-off-by: David S. Miller <davem@davemloft.net>

The patch "[SPARC64]: Get rid of fast IRQ feature"
moved the the code from arch/sparc64/kernel/entry.S:
      lduba           [%g7] ASI_PHYS_BYPASS_EC_E, %g5
      or              %g5, AUXIO_AUX1_FTCNT, %g5
      stba            %g5, [%g7] ASI_PHYS_BYPASS_EC_E
      andn            %g5, AUXIO_AUX1_FTCNT, %g5
      stba            %g5, [%g7] ASI_PHYS_BYPASS_EC_E
to arch/sparc64/kernel/irq.c:
              val = readb(auxio_register);
              val |= AUXIO_AUX1_FTCNT;
              writeb(val, auxio_register);
              val &= AUXIO_AUX1_FTCNT;
              writeb(val, auxio_register);
This looks like it it missing a bitwise not, which is reintroduced
by this patch.

Due to lack of a floppy device, I could not test it, but it looks
evident.
Signed-off-by: Bernhard R Link <brlink@debian.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

irq.c is missing the inclusion of asm/io.h, which causes
readb() and writeb() the be undefined.
Signed-off-by: Sven Hartge <hartge@ds9.argh.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

It is only used by some localized code in irq.c, and also
delete enable_prom_timer() as that is totally unused.
Signed-off-by: David S. Miller <davem@davemloft.net>

Do not cat bucket->irq_info to struct irqaction * directly,
but go through struct irq_desc *.
Signed-off-by: David S. Miller <davem@davemloft.net>

This allows a PCI controller to shim into IRQ delivery
so that DMA queues can be drained, if necessary.

If some bus specific code needs to run before an IRQ
handler is invoked, the bus driver simply needs to setup
the function pointer in bucket->irq_info->pre_handler and
the two args bucket->irq_info->pre_handler_arg[12].

The Schizo PCI driver is converted over to use a pre-handler
for the DMA write-sync processing it needs when a device
is behind a PCI->PCI bus deeper than the top-level APB
bridges.

While we're here, clean up all of the action allocation
and handling.  Now, we allocate the irqaction as part of
the bucket->irq_info area.  There is an array of 4 irqaction
(for PCI irq sharing) and a bitmask saying which entries
are active.

The bucket->irq_info is allocated at build_irq() time, not
at request_irq() time.  This simplifies request_irq() and
free_irq() tremendously.

The SMP dynamic IRQ retargetting code got removed in this
change too.  It was disabled for a few months now, and we
can resurrect it in the future if we want.
Signed-off-by: David S. Miller <davem@davemloft.net>

The only real user was the assembler floppy interrupt
handler, which does not need to be in assembly.

This makes it so that there are less pieces of code which
know about the internal layout of ivector_table[] and
friends.
Signed-off-by: David S. Miller <davem@davemloft.net>

There is some race whereby IRQs get stuck, the IRQ status
is pending but no processor actually handles the IRQ vector
and thus the interrupt.
 
This is a temporary workaround.
Signed-off-by: David S. Miller <davem@davemloft.net>

We would never advance the goal_cpu counter like we
should, so all IRQs would go to a single processor.
Signed-off-by: David S. Miller <davem@davemloft.net>

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!