sh: Avoid using IRQ0 on SH3 and SH4

IRQ0 is no longer returned by platform_get_irq() and its ilk -- they now
return -EINVAL instead. However, the kernel code supporting SH3/4-based
SoCs still maps the IRQ #s starting at 0 -- modify that code to start the
IRQ #s from 16 instead.

The patch should mostly affect the AP-SH4A-3A/AP-SH4AD-0A boards as they
indeed are using IRQ0 for the SMSC911x compatible Ethernet chip.

Fixes: ce753ad1549c ("platform: finally disallow IRQ0 in platform_get_irq() and its ilk")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Link: https://lore.kernel.org/r/71105dbf-cdb0-72e1-f9eb-eeda8e321696@omp.ru
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>

sh: intc: Avoid spurious sizeof-pointer-div warning

GCC warns about the pattern sizeof(void*)/sizeof(void), as it looks like
the abuse of a pattern to calculate the array size. This pattern appears
in the unevaluated part of the ternary operator in _INTC_ARRAY if the
parameter is NULL.

The replacement uses an alternate approach to return 0 in case of NULL
which does not generate the pattern sizeof(void*)/sizeof(void), but still
emits the warning if _INTC_ARRAY is called with a nonarray parameter.

This patch is required for successful compilation with -Werror enabled.

The idea to use _Generic for type distinction is taken from Comment #7
in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108483 by Jakub Jelinek

Signed-off-by: Michael Karcher <kernel@mkarcher.dialup.fu-berlin.de>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Link: https://lore.kernel.org/r/619fa552-c988-35e5-b1d7-fe256c46a272@mkarcher.dialup.fu-berlin.de
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

sh: intc: Kill off special reservation interface.

At present reserving the IRLs in the IRQ bitmap in addition to the
dropping of the legacy IRQ pre-allocation prevent IRL IRQs from being
allocated for the x3proto board.

The only reason to permit reservations was to lock down possible hardware
vectors prior to dynamic IRQ scanning, but this doesn't matter much given
that the hardware controller configuration is sorted before we get around
to doing any dynamic IRQ allocation anyways. Beyond that, all of the
tables are __init annotated, so quite a bit more work would need to be
done to support reconfiguring things like IRL controllers on the fly,
much more than would ever make it worth the hassle.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: intc: remove dependency on NR_IRQS

SH intc has a compile time dependency on NR_IRQS. Make this dependency a
local define so that shmobile (and ARM in general) can have run-time
NR_IRQS setting.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>

sh: intc: unify evt2irq/irq2evt macros for sh and arm

Move evt2irq and irq2evt macros definitions out of sh and arm includes
into a common location.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>

PM / shmobile: Don't include SH7372's INTCS in syscore suspend/resume

Since the SH7372's INTCS in included into syscore suspend/resume,
which causes the chip to be accessed when PM domains have been
turned off during system suspend, the A4R domain containing the
INTCS has to stay on during system sleep, which is suboptimal
from the power consumption point of view.

For this reason, add a new INTC flag, skip_syscore_suspend, to mark
the INTCS for intc_suspend() and intc_resume(), so that they don't
touch it. This allows the A4R domain to be turned off during
system suspend and the INTCS state is resrored during system
resume by the A4R's "power on" code.

Suggested-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Magnus Damm <damm@opensource.se>

sh: intc: Fix up initializers for gcc 4.5.

The _INTC_ARRAY() initializer presently does a NULL test which blows up
as a non-constant initializer under gcc 4.5. This switches over to a type
test to account for NULL initializers explicitly.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: Switch dynamic IRQ creation to generic irq allocator.

Now that the genirq code provides an IRQ bitmap of its own and the
necessary API to manipulate it, there's no need to keep our own version
around anymore.

In the process we kill off some unused IRQ reservation code, with future
users now having to tie in to the genirq API as normal.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: intc: Split up the INTC code.

This splits up the sh intc core in to something more vaguely resembling
a subsystem. Most of the functionality was alread fairly well
compartmentalized, and there were only a handful of interdependencies
that needed to be resolved in the process.

This also serves as future-proofing for the genirq and sparseirq rework,
which will make some of the split out functionality wholly generic,
allowing things to be killed off in place with minimal migration pain.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: intc: Handle early lookups of subgroup IRQs.

If lookups happen while the radix node still points to a subgroup
mapping, an IRQ hasn't yet been made available for the specified id, so
error out accordingly. Once the slot is replaced with an IRQ mapping and
the tag is discarded, lookup can commence as normal.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: intc: Support virtual mappings for IRQ subgroups.

Many interrupts that share a single mask source but are on different
hardware vectors will have an associated register tied to an INTEVT that
denotes the precise cause for the interrupt exception being triggered.

This introduces the concept of IRQ subgroups in the intc core, where
a virtual IRQ map is constructed for each of the pre-defined cause bits,
and a higher level chained handler takes control of the parent INTEVT.
This enables CPUs with heavily muxed IRQ vectors (especially across
disjoint blocks) to break things out in to a series of managed chained
handlers while being able to dynamically lookup and adopt the IRQs
created for them.

This is largely an opt-in interface, requiring CPUs to manually submit
IRQs for subgroup splitting, in addition to providing identifiers in
their enum maps that can be used for lazy lookup via the radix tree.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: intc: Implement reverse mapping for IRQs to per-controller IDs.

This implements a scheme roughly analogous to the PowerPC virtual to
hardware IRQ mapping, which we use for IRQ to per-controller ID mapping.
This makes it possible for drivers to use the IDs directly for lookup
instead of hardcoding the vector.

The main motivation for this work is as a building block for dynamically
allocating virtual IRQs for demuxing INTC events sharing a single INTEVT
in addition to a common masking source.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: Support early IRQ vector map reservation for delayed controllers.

Some controllers will need to be initialized lazily due to pinmux
constraints, while others may simply have no need to be brought online if
there are no backing devices for them attached. In this case it's still
necessary to be able to reserve their hardware vector map before dynamic
IRQs get a hold of them.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: intc: IRQ auto-distribution support.

This implements support for hardware-managed IRQ balancing as implemented
by SH-X3 cores (presently only hooked up for SH7786, but can probably be
carried over to other SH-X3 cores, too).

CPUs need to specify their distribution register along with the mask
definitions, as these follow the same format. Peripheral IRQs that don't
opt out of balancing will be automatically distributed at the whim of the
hardware block, while each CPU needs to verify whether it is handling the
IRQ or not, especially before clearing the mask.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: intc: userimask support.

This adds support for hardware-assisted userspace irq masking for
special priority levels. Due to the SR.IMASK interactivity, only some
platforms implement this in hardware (including but not limited to
SH-4A interrupt controllers, and ARM-based SH-Mobile CPUs). Each CPU
needs to wire this up on its own, for now only SH7786 is wired up as an
example.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: INTC ioremap support

Extend the INTC code with ioremap() support V2.

Support INTC controllers that are not accessible through
a 1:1 virt:phys window. Needed by SH-Mobile ARM INTCS.

The INTC code behaves as usual if the io window resource
is omitted. The slow phys->virt lookup only happens during
setup. The fast path code operates on virtual addresses.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: add INTC out of memory error handling

Extend the INTC code to warn and return an error code
in the case of memory allocation failure.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: extend INTC with force_disable

Extend the shared INTC code with force_disable support to
allow keeping mask bits statically disabled. Needed for
SDHI support to mask out unsupported interrupt sources.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: extend INTC with force_enable

Extend the shared INTC code with force_enable support to
allow keeping mask bits statically enabled. Needed by
upcoming INTC SDHI patches that mux together a bunch of
vectors to a single linux interrupt which is masked by
a priority register, but needs individual mask bits
constantly enabled.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: extend INTC with struct intc_hw_desc

This patch updates the INTC code by moving all vectors,
groups and registers from struct intc_desc to struct
intc_hw_desc.

The idea is that INTC tables should go from using the
macro(s) DECLARE_INTC_DESC..() only to using struct
intc_desc with name and hw initialized using the macro
INTC_HW_DESC(). This move makes it easy to initialize
an extended struct intc_desc in the future.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: intc: Handle legacy IRQ reservation in vector map.

Different CPUs will have different starting vectors, with varying
amounts of reserved or unusable vector space prior to the first slot.
This introduces a legacy vector reservation system that inserts itself in
between the CPU vector map registration and the platform specific IRQ
setup. This works fine in practice as the only new vectors that boards
need to establish on their own should be dynamically allocated rather
than arbitrarily assigned. As a plus, this also makes all of the
converted platforms sparseirq ready.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: intc: Make ack_regs generally available.

Currently this is ifdef'ed under SH-3 and SH-4A, but there are other CPUs
that will need this as well. Given the size of the existing data
structures, this doesn't cause any additional cacheline utilization for
the existing users, so has no direct impact on the data structures.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: Simplify "multi-evt" interrupt handling.

This patch changes the way in which "multi-evt" interrups are handled.
The intc_evt2irq_table and related intc_evt2irq() have been removed and
the "redirecting" handler is installed for the coupled interrupts.

Thanks to that the do_IRQ() function don't have to use another level
of indirection for all the interrupts...

Signed-off-by: Pawel Moll <pawel.moll@st.com>
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: multiple vectors per irq - base

Instead of keeping the single vector -> single linux irq mapping
we extend the intc code to support merging of vectors to a single
linux irq. This helps processors such as sh7750, sh7780 and sh7785
which have more vectors than masking ability. With this patch in
place we can modify the intc tables to use one irq per maskable
irq source. Please note the following:

- If multiple vectors share the same enum then only the
first vector will be available as a linux irq.

- Drivers may need to be rewritten to get pending irq
source from the hardware block instead of irq number.

This patch together with the sh7785 specific intc tables solves
DMA controller irq issues related to buggy interrupt masking.

Reported-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: Move the shared INTC code out to drivers/sh/

The INTC code will be re-used across different architectures, so move
this out to drivers/sh/ and include/linux/sh_intc.h respectively.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>