An interrupt controller may often implicitly inherit itself from a parent
node when in fact the controller is the interrupt root controller. Guard
against the case of child == parent and return NULL in this case.

This can also be fixed by adding an explicit "interrupt-parent;" to a root
interrupt controller node.

Based on code from Grant Likely.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Cc: Grant Likely <grant.likely@secretlab.ca>

We have platform code that needs to find a node's interrupt parent, so
export of_irq_find_parent() so we can use it.
Signed-off-by: NMichael Ellerman <michael@ellerman.id.au>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Instead of referencing NO_IRQ in platform.c, define some helper functions
in irq.c to call instead from platform.c.  Keep NO_IRQ usage local to
irq.c, and define NO_IRQ if not defined in headers.
Signed-off-by: NAndres Salomon <dilinger@queued.net>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

This patch fixes some instances where interrupt specifiers are
dereferenced directly instead of doing a be32_to_cpu() conversion first.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

The flat tree code wasn't fixing the endianness on phandle values when
unflattening the tree, and the code in drivers/of wasn't always doing a
be32_to_cpu before trying to dereference the phandle values.  This patch
fixes them.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

Resource names appear in human readable output, so when extracting IRQ
and address resources from a device tree node, use the full node name
to give proper context in places like /proc/iomem.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
CC: Michal Simek <monstr@monstr.eu>
CC: Stephen Rothwell <sfr@canb.auug.org.au>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: microblaze-uclinux@itee.uq.edu.au
CC: linuxppc-dev@ozlabs.org

Fix some endian issues in the irq mapping OF code.
Signed-off-by: NRob Herring <r.herring@freescale.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
CC: Michal Simek <monstr@monstr.eu>
CC: Wolfram Sang <w.sang@pengutronix.de>
CC: Stephen Rothwell <sfr@canb.auug.org.au>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Merge common irq mapping code between PowerPC and Microblaze.

This patch merges of_irq_find_parent(), of_irq_map_raw() and
of_irq_map_one().  The functions are dependent on one another, so all
three are merged in a single patch.  Other than cosmetic difference
(ie. DBG() vs. pr_debug()), the implementations are identical.

of_irq_to_resource() is also merged, but in this case the
implementations are different.  This patch drops the microblaze version
and uses the powerpc implementation unchanged.  The microblaze version
essentially open-coded irq_of_parse_and_map() which it does not need
to do.  Therefore the powerpc version is safe to adopt.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
CC: Michal Simek <monstr@monstr.eu>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Stephen Rothwell <sfr@canb.auug.org.au>

Merge common code between PowerPC and Microblaze.  SPARC implements
irq_of_parse_and_map(), but the implementation is different, so it
does not use this code.
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Jeremy Kerr <jeremy.kerr@canonical.com>