Move the IRQ stub generation to assembly to simplify it and for
consistency with 32 bits.  Doing it in a C file with asm() statements
doesn't help clarity, and it prevents some optimizations.

Shrink the IRQ stubs down to just over four bytes per (we fit seven
into a 32-byte chunk.)  This shrinks the total icache consumption of
the IRQ stubs down to an even kilobyte, if all of them are in active
use.

The downside is that we end up with a double jump, which could have a
negative effect on some pipelines.  The double jump is always inside
the same cacheline on any modern chips.

To get the most effect, cache-align the IRQ stubs.

This makes the 64-bit code match changes already done to the 32-bit
code, and should open up irqinit*.c for unification.
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>

Remove the leftover of sparseirqs.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

change names:

          irq_desc() ==> irq_desc_alloc
	__irq_desc() ==> irq_desc

Also split a few of the uses in lowlevel x86 code.

v2: need to check if desc is null in smp_irq_move_cleanup
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

There are a handful of loops that go from 0 to nr_irqs and use
get_irq_desc() on them. These would allocate all the irq_desc
entries, regardless of the need for them.

Use the smarter for_each_irq_desc() iterator that will only iterate
over the present ones.

v2: make sure arch without GENERIC_HARDIRQS work too
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

add CONFIG_HAVE_SPARSE_IRQ to for use condensed array.
Get rid of irq_desc[] array assumptions.

Preallocate 32 irq_desc, and irq_desc() will try to get more.

( No change in functionality is expected anywhere, except the odd build
  failure where we missed a code site or where a crossing commit itroduces
  new irq_desc[] usage. )

v2: according to Eric, change get_irq_desc() to irq_desc()
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

also add first_free_entry and pin_map_size, which were NR_IRQS derived
constants.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

also change two functions to static.
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Provide apic_intr_init and smp_intr_init functions.
Signed-off-by: NGlauber Costa <gcosta@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Commit 9d25d4db ("x86: BUILD_IRQ say
.text to avoid .data.percpu") added a ".text" specifier to make sure
that BUILD_IRQ() builds the irq trampoline in the text segment rather
than in some random left-over segment that the compiler happened to
leave the asm in.

However, we should also make sure that we switch back by adding a
".previous" at the end, so that there are no subtle issues with
subsequent compiler-generated code.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When I edit the x86_64 Makefile to -fno-unit-at-a-time, bootup panics
on 0xCCs in IRQ0x3e_interrupt(): IRQ0x20_interrupt etc. have got linked
into .data.percpu.  Perhaps there are other ways of triggering that:
specify ".text" in the BUILD_IRQ() macro for safety.

I've been using -fno-unit-at-a-time (to lessen inlining, for easier
debugging) for a long time.
Signed-off-by: NHugh Dickins <hugh@veritas.com>
Cc: Mike Travis <travis@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The leftovers of the i8259 unification have nothing to do with i8259
at all. They contain interrupt init code and the i8259_xx name is just
misleading now.

Rename them to irqinit_32/64.c
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Make conversion of i8259 very mechanical -- i8259 was generated by
 diff -D, with too different parts left in i8259_32 and
i8259_64.c. Only "by hand" changes were removal of #ifdef from middle
of the comment (prevented compilation) and removal of one static to
allow splitting into files.

Of course, it will need some cleanups now, and those will follow.
Signed-of-by: NPavel Machek <pavel@suse.cz>

The leftovers of the i8259 unification have nothing to do with i8259
at all. They contain interrupt init code and the i8259_xx name is just
misleading now.

Rename them to initirq_32/64.c
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Make conversion of i8259 very mechanical -- i8259 was generated by

The SGI UV system needs several more system vectors than a vanilla
x86_64 system.  Rather than burden the other archs with extra system
vectors that they don't use, change FIRST_SYSTEM_VECTOR to a variable,
so that it can be dynamic.
Signed-off-by: NAlan Mayer <ajm@sgi.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

i8259_64.c is the only place which uses those macros.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

x86_64 lacks a native_init_IRQ() function, so we turn the arch's
init_IRQ() function into a native construct
Signed-off-by: NGlauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Rather than remove and/or mangle inb_p/outb_p we want to remove the use
of them from inappropriate places. For the PIC/PIT this may eventually
depend on 32/64bitism or similar so start by adding inb/outb_pit and
inb/outb_pic so that we can make them use any scheme we settle on without
disturbing the existing, correct (for ISA), port 0x80 usage. (eg we can
make inb_pit use udelay without messing up inb_p).

Floppy already does this for the fdc. That really only leaves the CMOS as
a core logic item to tackle, and bits of parallel port handling in the
chipset layers.
Signed-off-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

The array is never written, and on 64-bits it's not even being used
past initial boot.
Signed-off-by: NJan Beulich <jbeulich@novell.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Howdy! Here's a simple janitorish patch for you:

This patch mainly hinges around two includes and their ramifications:

#include <i8259.h>	which provides cached_{slave,master}_mask
#include <io_ports.h>	which provides PIC_{MASTER,SLAVE}_{IMR,CMD}

Adding these two includes and using those half dozen or so definitions
removed 140+ lines of diffs between i8259_32.c and i8259_64.c, thus
making it easier for the real substantitive differences between them to
show up, and hopefully therefore making it easier to eventually merge
the two.  All the warnings that checkpatch.pl throws (missing spaces
after commas and >80 character lines) exist intentionally to match
i8259_32.c.
Signed-off-by: NPaul Jimenez <pj@place.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

All kobjects require a dynamically allocated name now. We no longer
need to keep track if the name is statically assigned, we can just
unconditionally free() all kobject names on cleanup.
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

more struct irqaction initializer cleanups.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Finally switch to the clockevents code. Share code with i386 for
hpet and PIT.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NChris Wright <chrisw@sous-sol.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Some interrupt entry points are currently defined in i8259.c They probably
belong in a header.  Right now, their only user is init_IRQ, justifying
their declaration in-file.  But when virtualization comes in, we may be
interested in using that functions in late initializations.
Signed-off-by: NGlauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NYinghai Lu <yinghai.lu@amd.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The problem:  After moving an interrupt when is it safe to teardown
the data structures for receiving the interrupt at the old location?

With a normal pci device it is possible to issue a read to a device
to flush all posted writes.  This does not work for the oldest ioapics
because they are on a 3-wire apic bus which is a completely different
data path.  For some more modern ioapics when everything is using
front side bus delivery you can flush interrupts by simply issuing a
read to the ioapic.  For other modern ioapics emperical testing has
shown that this does not work.

So it appears the only reliable way to know the last of the irqs from an
ioapic have been received from before the ioapic was reprogrammed is to
received the first irq from the ioapic from after it was reprogrammed.

Once we know the last irq message has been received from an ioapic
into a local apic we then need to know that irq message has been
processed through the local apics.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

For the ISA irqs we reserve 16 vectors.  This patch adds constants for
those vectors and modifies the code to use them.  Making the code a
little clearer and making it possible to move these vectors in the future.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The code in io_apic.c and in i8259.c currently hardcode the same
vector for the timer interrupt so there is no reason for a special
assignment for the timer as the setup for the i8259 already takes care
of this.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Never mask interrupts immediately upon request.  Disabling interrupts in
high-performance codepaths is rare, and on the other hand this change could
recover lost edges (or even other types of lost interrupts) by conservatively
only masking interrupts after they happen.  (NOTE: with this change the
highlevel irq-disable code still soft-disables this IRQ line - and if such an
interrupt happens then the IRQ flow handler keeps the IRQ masked.)

Mark i8529A controllers as 'never loses an edge'.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

interrupt array is referred for idt vectors instead of NR_IRQS, so change size
to NR_VECTORS - FIRST_EXTERNAL_VECTOR. Also change to static.
Signed-off-by: NYinghai Lu <yinghai@amd.com>
Signed-off-by: NAndi Kleen <ak@suse.de>

Introduce desc->name and eliminate the handle_irq_name() hack.  Add
set_irq_chip_and_handler_name() to set the flow type and name at once.
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This refactors the irq handling code to make the vectors a per cpu resource so
the same vector number can be simultaneously used on multiple cpus for
different irqs.

This should make systems that were hitting limits on the total number of irqs
much more livable.

[akpm@osdl.org: build fix]
[akpm@osdl.org: __target_IO_APIC_irq is unneeded on UP]
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This is a small pessimization but it paves the way for making this information
per cpu.  Which allows the the maximum number of IRQS to become NR_CPUS*224.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Rajesh Shah <rajesh.shah@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch converts all the x86_64 PIC controllers layers to the new and
simpler irq-chip interrupt handling layer.

[mingo@elte.hu: The patch also enables the fasteoi handler for x86_64]
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Roland Dreier <rolandd@cisco.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Got it. i8259A_resume calls init_8259A(0) unconditionally, even if
auto_eoi has been set. Keep track of the current status and restore that
on resume. This fixes it for AMD64 and i386.
Signed-off-by: NMatthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: NAndi Kleen <ak@suse.de>