NO_IRQ has been == 0 on powerpc for just over ten years (since commit
0ebfff14 ("[POWERPC] Add new interrupt mapping core and change
platforms to use it")). It's also 0 on most other arches.

Although it's fairly harmless, every now and then it causes confusion
when a driver is built on powerpc and another arch which doesn't define
NO_IRQ. There's at least 6 definitions of NO_IRQ in drivers/, at least
some of which are to work around that problem.

So we'd like to remove it. This is fairly trivial in the arch code, we
just convert:

    if (irq == NO_IRQ)	to	if (!irq)
    if (irq != NO_IRQ)	to	if (irq)
    irq = NO_IRQ;	to	irq = 0;
    return NO_IRQ;	to	return 0;

And a few other odd cases as well.

At least for now we keep the #define NO_IRQ, because there is driver
code that uses NO_IRQ and the fixes to remove those will go via other
trees.

Note we also change some occurrences in PPC sound drivers, drivers/ps3,
and drivers/macintosh.
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

The irq_domain_ops are not modified by the driver and the irqdomain core
code accepts pointer to a const data.
Signed-off-by: NKrzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

Each revmap type has different arguments for setting up the revmap.
This patch splits up the generator functions so that each revmap type
can do its own setup and the user doesn't need to keep track of how
each revmap type handles the arguments.

This patch also adds a host_data argument to the generators.  There are
cases where the host_data pointer will be needed before the function returns.
ie. the legacy map calls the .map callback for each irq before returning.

v2: - Add void *host_data argument to irq_domain_add_*() functions
    - fixed failure to compile
    - Moved IRQ_DOMAIN_MAP_* defines into irqdomain.c
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: NOlof Johansson <olof@lixom.net>

This patch drops the powerpc-specific irq_host structures and uses the common
irq_domain strucutres defined in linux/irqdomain.h.  It also fixes all
the users to use the new structure names.

Renaming irq_host to irq_domain has been discussed for a long time, and this
patch is a step in the process of generalizing the powerpc virq code to be
usable by all architecture.

An astute reader will notice that this patch actually removes the irq_host
structure instead of renaming it.  This is because the irq_domain structure
already exists in include/linux/irqdomain.h and has the needed data members.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Milton Miller <miltonm@bga.com>
Tested-by: NOlof Johansson <olof@lixom.net>

First step in eliminating irq_map[] table entirely
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Scripted with coccinelle.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Use the proper accessors instead of open access to irq_desc.
Converted with coccinelle.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Signed-off-by: NLennert Buytenhek <buytenh@secretlab.ca>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

get_irq_desc() is a powerpc-specific version of irq_to_desc(). That
is reason enough to remove it, but it also doesn't know about sparse
irq_desc support which irq_to_desc() does (when we enable it).
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Compatible names should refer to a specific version of the hardware,
without wildcards.  Change each instance of mv64x60 to mv64360, which
is the oldest version we currently support.
Signed-off-by: NMark A. Greer <mgreer@mvista.com>
Signed-off-by: NDale Farnsworth <dale@farnsworth.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The most common match semantic is an exact match based on the device node.
So provide a default implementation that does this, and hook it up if no
match routine is specified.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The majority of irq_host implementations (3 out of 4) are associated
with a device_node, and need to stash it somewhere. Rather than having
it somewhere different for each host, add an optional device_node pointer
to the irq_host structure.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

There are 3 interrupt groups each with its own status/mask registers.
We use a separate struct irq_chip for each interrupt group and handle
interrupts in two stages or levels: level 1 selects the appropriate
struct irq_chip, and level 2 selects individual interrupts within
that irq_chip.
Signed-off-by: NDale Farnsworth <dale@farnsworth.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>