regmap: mmio: Remove unused 64-bit support code

regmap API does not support 64-bit data size, so
there is no point to have it in regmap MMIO.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux

regmap: mmio: Remove unused 64-bit support code

regmap API does not support 64-bit data size, so
there is no point to have it in regmap MMIO.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230622183613.58762-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Allow passing an empty config->reg_stride

Regmap's stride is used for MMIO regmaps to check the correctness of
reg_width. However, it's acceptable to pass an empty config->reg_stride,

regmap: mmio: Allow passing an empty config->reg_stride

Regmap's stride is used for MMIO regmaps to check the correctness of
reg_width. However, it's acceptable to pass an empty config->reg_stride,
in that case the actual stride used is 1.

There are valid cases now to pass an empty stride, when using
down/upshifting of register address. In this case, the stride value
loses its sense, so ignore the reg_width when the stride isn't set.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com
Link: https://lore.kernel.org/r/20230511142735.316445-1-maxime.chevallier@bootlin.com
Signed-off-by: Mark Brown <broonie@kernel.org

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regmap: mmio: replace return 0 with break in switch statement

Variable min_stride is assigned a value that is never read, fix this by
replacing the return 0 with a break statement. This also makes t

regmap: mmio: replace return 0 with break in switch statement

Variable min_stride is assigned a value that is never read, fix this by
replacing the return 0 with a break statement. This also makes the case
statement consistent with the other cases in the switch statement.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20220922080445.818020-1-colin.i.king@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Use swabXX_array() helpers

Since we have a few helpers to swab elements of a given size in an array
use them instead of open coded variants.

Signed-off-by: Andy Shevchenko <andriy.she

regmap: mmio: Use swabXX_array() helpers

Since we have a few helpers to swab elements of a given size in an array
use them instead of open coded variants.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220831212744.56435-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Fix rebase error

A dangling pointless "ret 0" was left in and some unneeded
whitespace can go too.

Fixes: 81c0386c1376 ("regmap: mmio: Support accelerared noinc operations")
Reported-

regmap: mmio: Fix rebase error

A dangling pointless "ret 0" was left in and some unneeded
whitespace can go too.

Fixes: 81c0386c1376 ("regmap: mmio: Support accelerared noinc operations")
Reported-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220831141303.501548-1-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Support accelerared noinc operations

Use the newly added callback for accelerated noinc MMIO
to provide writesb, writesw, writesl, writesq, readsb, readsw,
readsl and readsq.

A specia

regmap: mmio: Support accelerared noinc operations

Use the newly added callback for accelerated noinc MMIO
to provide writesb, writesw, writesl, writesq, readsb, readsw,
readsl and readsq.

A special quirk is needed to deal with big endian regmaps: there
are no accelerated operations defined for big endian, so fall
back to calling the big endian operations itereatively for this
case.

The Hexagon architecture turns out to have an incomplete
<asm/io.h>: writesb() is not implemented. Fix this by doing
what other architectures do: include <asm-generic/io.h> into
the <asm/io.h> file.

Cc: Brian Cain <bcain@quicinc.com>
Cc: linux-hexagon@vger.kernel.org
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20220816204832.265837-2-linus.walleij@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Fix MMIO accessors to avoid talking to IO port

Currently regmap MMIO is inconsistent with IO accessors. I.e.
the Big Endian counterparts are using ioreadXXbe() / iowriteXXbe()
which ar

regmap: mmio: Fix MMIO accessors to avoid talking to IO port

Currently regmap MMIO is inconsistent with IO accessors. I.e.
the Big Endian counterparts are using ioreadXXbe() / iowriteXXbe()
which are not clean implementations of readXXbe().

That said, reimplement current Big Endian MMIO accessors by replacing
ioread()/iowrite() with respective read()/write() and swab() calls.

Note, there are no current in-kernel users that may utilize the
functionality of the IO ports on Big Endian hardware. All drivers
that use regmap MMIO either Little Endian, or they don't map IO
ports in a way that ioreadXX()/iowriteXX() may be utilized.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: William Breathitt Gray <william.gray@linaro.org>
Link: https://lore.kernel.org/r/20220808203401.35153-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Introduce IO accessors that can talk to IO port

Some users may use regmap MMIO for IO ports, and this can be done
by assigning ioreadXX()/iowriteXX() and their Big Endian counterparts

regmap: mmio: Introduce IO accessors that can talk to IO port

Some users may use regmap MMIO for IO ports, and this can be done
by assigning ioreadXX()/iowriteXX() and their Big Endian counterparts
to the regmap context.

Add IO port support with a corresponding flag added.

While doing that, make sure that user won't select relaxed MMIO access
along with IO port because the latter have no relaxed variants.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: William Breathitt Gray <william.gray@linaro.org>
Link: https://lore.kernel.org/r/20220808203401.35153-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Get rid of broken 64-bit IO

The current implementation, besides having no active users, is broken
by design of regmap. For 64-bit IO we need to supply 64-bit value,
otherwise there is

regmap: mmio: Get rid of broken 64-bit IO

The current implementation, besides having no active users, is broken
by design of regmap. For 64-bit IO we need to supply 64-bit value,
otherwise there is no way to handle upper 32 bits in 64-bit register.

Hence, remove the broken IO accessors for good and wait for real user
that can fix entire regmap API for that.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: William Breathitt Gray <william.gray@linaro.org>
Link: https://lore.kernel.org/r/20220808203401.35153-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Remove mmio_relaxed member from context

There is no need to keep mmio_relaxed member in the context, it's
onetime used during generation of the context. Remove it.

Signed-off-by: Andy

regmap: mmio: Remove mmio_relaxed member from context

There is no need to keep mmio_relaxed member in the context, it's
onetime used during generation of the context. Remove it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: William Breathitt Gray <william.gray@linaro.org>
Link: https://lore.kernel.org/r/20220808203401.35153-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: Prefer unsigned int to bare use of unsigned

Fix checkpatch warnings:
WARNING: Prefer 'unsigned int' to bare use of 'unsigned'

Signed-off-by: Jinchao Wang <wjc@cdjrlc.com>
Link: https://

regmap: Prefer unsigned int to bare use of unsigned

Fix checkpatch warnings:
WARNING: Prefer 'unsigned int' to bare use of 'unsigned'

Signed-off-by: Jinchao Wang <wjc@cdjrlc.com>
Link: https://lore.kernel.org/r/20210628171907.63646-1-wjc@cdjrlc.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: add config option to allow relaxed MMIO accesses

On some platforms (eg armv7 due to the CONFIG_ARM_DMA_MEM_BUFFERABLE)
MMIO R/W operations always add memory barriers which can increase

regmap: mmio: add config option to allow relaxed MMIO accesses

On some platforms (eg armv7 due to the CONFIG_ARM_DMA_MEM_BUFFERABLE)
MMIO R/W operations always add memory barriers which can increase load,
decrease battery life or in general reduce performance unnecessarily
on devices which access a lot of configuration registers and where
ordering does not matter (eg. media accelerators like the Verisilicon /
Hantro video decoders).

Drivers used to call the relaxed MMIO variants directly but since they
are now accessing the MMIO registers via regmaps (to compensate for
different VPU HW reg layouts via regmap fields), there is a need for a
relaxed API / config to preserve existing behaviour.

Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Adrian Ratiu <adrian.ratiu@collabora.com>
Link: https://lore.kernel.org/r/20201014203024.954369-1-adrian.ratiu@collabora.com
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: add proper SPDX identifiers on files that did not have them.

There were a few files in the regmap code that did not have SPDX
identifiers on them, so fix that up. At the same time, remove t

regmap: add proper SPDX identifiers on files that did not have them.

There were a few files in the regmap code that did not have SPDX
identifiers on them, so fix that up. At the same time, remove the "free
form" text that specified the license of the file, as that is impossible
for any tool to properly parse.

Also, as Mark loves // comment markers, convert all of the headers to be
the same to make things look consistent :)

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: Skip clk_put for attached clocks when freeing context

Capability to attach an existing clk to a MMIO regmap was
introduced in 4.17rc1.

However, when using attached clk, regmap does not do t

regmap: Skip clk_put for attached clocks when freeing context

Capability to attach an existing clk to a MMIO regmap was
introduced in 4.17rc1.

However, when using attached clk, regmap does not do the clk_get.
Therefore it should not do the clk_put when freeing the MMIO
regmap context.

There does not appear to be any users of attached clocks yet
so this would be a good time to make this change before anything
depends on the existing behaviour.

Signed-off-by: James Kelly <jamespeterkelly@gmail.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Add function to attach a clock

regmap_init_mmio_clk allows to specify a clock that needs to be enabled
while accessing the registers.

However, that clock is retrieved through its cloc

regmap: mmio: Add function to attach a clock

regmap_init_mmio_clk allows to specify a clock that needs to be enabled
while accessing the registers.

However, that clock is retrieved through its clock ID, which means it will
lookup that clock based on the current device that registers the regmap,
and, in the DT case, will only look in that device OF node.

This might be problematic if the clock to enable is stored in another node.
Let's add a function that allows to attach a clock that has already been
retrieved to a regmap in order to fix this.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Explicitly say little endian is the defualt in the bus config

Otherwise the DT parsing will default to big endian if nothing is
specified.

Reported-by: Krzysztof Kozlowski <k.kozlowsk

regmap: mmio: Explicitly say little endian is the defualt in the bus config

Otherwise the DT parsing will default to big endian if nothing is
specified.

Reported-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Parse endianness definitions from DT

Since we changed to do formatting in the bus we now skip all the format
parsing that the core does for its data marshalling code. This means
that

regmap: mmio: Parse endianness definitions from DT

Since we changed to do formatting in the bus we now skip all the format
parsing that the core does for its data marshalling code. This means
that we skip the DT parsing it does which breaks some systems, we need
to add an explict call in the MMIO code to do this.

Reported-by: Alexander Stein <alexander.stein@systec-electronic.com>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Fix value endianness selection

Currently when selecting value endianness we check the register
endiannes, not the value endianness.

Reported-by: Alexander Stein <alexander.stein@syste

regmap: mmio: Fix value endianness selection

Currently when selecting value endianness we check the register
endiannes, not the value endianness.

Reported-by: Alexander Stein <alexander.stein@systec-electronic.com>
Tested-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Convert to regmap_bus and fix accessor usage

Currently regmap-mmio uses the __raw accessors to read and write from
memory. This is not safe as these interact poorly with spinlocks and

regmap: mmio: Convert to regmap_bus and fix accessor usage

Currently regmap-mmio uses the __raw accessors to read and write from
memory. This is not safe as these interact poorly with spinlocks and
are not guaranteed to generate emulated instructions on at least ARM
where regmap is commonly used. The APIs that are provided all provide
some byte swapping so this is difficult to do with the current
regmap-mmio implementation which attempts to use the regmap core byte
swapping.

We can fix this by modernising the MMIO implementation to use
reg_read() and reg_write() operations which were added after the API was
implemented and pass simple unsigned integers through to the bus, making
use of the formatting provided by the I/O accessors using a similar
pattern to that used by the core. This will be less efficient for block
I/O operations since we now enable and disable any required clocks per
register but it is not clear that any users of regmap-mmio actually use
block I/O and there is room to optimise later.

This removes support for big endian I/O on 64 bit registers since no I/O
accessors are provided, no current users were found and support can be
added easily once they are available.

In addition make the default endianness little endian. This was the
behaviour prior to 29bb45f25ff305 (regmap-mmio: Use native endianness
for read/write) and is the behaviour desired by most existing users, the
users have been audited and those that need native endianness converted
to request it explicitly. Previously native was documented as the
default but due to the byte swapping in the accessors this was not
correctly implemented.

Fixes: 29bb45f25ff305 (regmap-mmio: Use native endianness for read/write)
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Tested-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Revert to v4.4 endianness handling

Commit 29bb45f25ff3 (regmap-mmio: Use native endianness for read/write)
attempted to fix some long standing bugs in the MMIO implementation for
big e

regmap: mmio: Revert to v4.4 endianness handling

Commit 29bb45f25ff3 (regmap-mmio: Use native endianness for read/write)
attempted to fix some long standing bugs in the MMIO implementation for
big endian systems caused by duplicate byte swapping in both regmap and
readl()/writel() which affected MIPS systems as when they are in big
endian mode they flip the endianness of all registers in the system, not
just the CPU. MIPS systems had worked around this by declaring regmap
using IPs as little endian which is inaccurate, unfortunately the issue
had not been reported.

Sadly the fix makes things worse rather than better. By changing the
behaviour to match the documentation it caused behaviour changes for
other IPs which broke them and by using the __raw I/O accessors to avoid
the endianness swapping in readl()/writel() it removed some memory
ordering guarantees and could potentially generate unvirtualisable
instructions on some architectures.

Unfortunately sorting out all this mess in any half way sensible fashion
was far too invasive to go in during an -rc cycle so instead let's go
back to the old broken behaviour for v4.5, the better fixes are already
queued for v4.6. This does mean that we keep the broken MIPS DTs for
another release but that seems the least bad way of handling the
situation.

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: Add regmap_mmio_get_min_stride

Splite the minimal stride parsing into one signal function.

Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com>
Signed-off-by: Mark Brown <broonie@ke

regmap: mmio: Add regmap_mmio_get_min_stride

Splite the minimal stride parsing into one signal function.

Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: mmio: remove the useless code

Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

regmap-mmio: Use native endianness for read/write

The regmap API has an endianness setting for formatting reads and writes.
This can be set by the usual DT "little-endian" and "big-endian" propertie

regmap-mmio: Use native endianness for read/write

The regmap API has an endianness setting for formatting reads and writes.
This can be set by the usual DT "little-endian" and "big-endian" properties.
To work properly the associated regmap_bus needs to read/write in native
endian.

The "syscon" DT device binding creates an mmio-based regmap_bus which
performs all reads/writes as little-endian. These values are then converted
again by regmap, which means that all of the MIPS BCM boards (which are
big-endian) have been declared as "little-endian" to get regmap to convert
them back to big-endian.

Modify regmap-mmio to use the native-endian functions __raw_read*() and
__raw_write*() instead of the little-endian functions read*() and
write*().

Modify the big-endian MIPS BCM boards to use what will now be the correct
endianness instead of pretending that the devices are little-endian.

Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: Move documentation to regmap.h

Init functions defined in regmap*.c files are now prefixed with
__, take lockdep key and class parameters, and should not be
called directly: move the document

regmap: Move documentation to regmap.h

Init functions defined in regmap*.c files are now prefixed with
__, take lockdep key and class parameters, and should not be
called directly: move the documentation to regmap.h, where the
macros are defined.

Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

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regmap: Use different lockdep class for each regmap init call

Lockdep validator complains about recursive locking and deadlock
when two different regmap instances are called in a nested order.
That

regmap: Use different lockdep class for each regmap init call

Lockdep validator complains about recursive locking and deadlock
when two different regmap instances are called in a nested order.
That happens anytime a regmap read/write call needs to access
another regmap.

This is because, for performance reason, lockdep groups all locks
initialized by the same mutex_init() in the same lock class.
Therefore all regmap mutexes are in the same lock class, leading
to lockdep "nested locking" warnings if a regmap accesses another
regmap.

In general, it is impossible to establish in advance the hierarchy
of regmaps, so we make sure that each regmap init call initializes
its own static lock_class_key. This is done by wrapping all
regmap_init calls into macros.

This also allows us to give meaningful names to the lock_class_key.
For example, in rt5677 case, we have in /proc/lockdep_chains:
irq_context: 0
[ffffffc0018d2198] &dev->mutex
[ffffffc0018d2198] &dev->mutex
[ffffffc001bd7f60] rt5677:5104:(&rt5677_regmap)->_lock
[ffffffc001bd7f58] rt5677:5096:(&rt5677_regmap_physical)->_lock
[ffffffc001b95448] &(&base->lock)->rlock

The above would have resulted in a lockdep recursive warning
previously. This is not the case anymore as the lockdep validator
now clearly identifies the 2 regmaps as separate.

Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

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