hwspinlock: Remove unused hwspin_lock_get_id()

hwspin_lock_get_id() has been unused since the original 2011
commit bd9a4c7df256 ("drivers: hwspinlock: add framework")

Remove it and the correspondin

hwspinlock: Remove unused hwspin_lock_get_id()

hwspin_lock_get_id() has been unused since the original 2011
commit bd9a4c7df256 ("drivers: hwspinlock: add framework")

Remove it and the corresponding docs.

Note that the of_hwspin_lock_get_id() version is still in use,
so leave that alone.

Signed-off-by: Dr. David Alan Gilbert <[email protected]>
Reviewed-by: Baolin Wang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bjorn Andersson <[email protected]>

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hwspinlock: Remove unused (devm_)hwspin_lock_request()

devm_hwspin_lock_request() was added by 2018's
commit 4f1acd758b08 ("hwspinlock: Add devm_xxx() APIs to request/free
hwlock") however, it's nev

hwspinlock: Remove unused (devm_)hwspin_lock_request()

devm_hwspin_lock_request() was added by 2018's
commit 4f1acd758b08 ("hwspinlock: Add devm_xxx() APIs to request/free
hwlock") however, it's never been used, everyone uses the
devm_hwspin_lock_request_specific() call instead.

Remove it.

Similarly, the none-devm variant isn't used.
Remove it, and the referring documentation.

Signed-off-by: Dr. David Alan Gilbert <[email protected]>
Reviewed-by: Baolin Wang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bjorn Andersson <[email protected]>

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hwspinlock: Introduce hwspin_lock_bust()

When a remoteproc crashes or goes down unexpectedly this can result in
a state where locks held by the remoteproc will remain locked possibly
resulting in de

hwspinlock: Introduce hwspin_lock_bust()

When a remoteproc crashes or goes down unexpectedly this can result in
a state where locks held by the remoteproc will remain locked possibly
resulting in deadlock. This new API hwspin_lock_bust() allows
hwspinlock implementers to define a bust operation for freeing previously
acquired hwspinlocks after verifying ownership of the acquired lock.

Signed-off-by: Richard Maina <[email protected]>
Reviewed-by: Bjorn Andersson <[email protected]>
Signed-off-by: Chris Lew <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bjorn Andersson <[email protected]>

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hwspinlock: add the 'in_atomic' API

Add the 'in_atomic' mode which can be called from an atomic context.
This mode relies on the existing 'raw' mode (no lock, no preemption/irq
disabling) with the d

hwspinlock: add the 'in_atomic' API

Add the 'in_atomic' mode which can be called from an atomic context.
This mode relies on the existing 'raw' mode (no lock, no preemption/irq
disabling) with the difference that the timeout is not based on jiffies
(jiffies won't increase when irq are disabled) but handled with
busy-waiting udelay() calls.

Signed-off-by: Fabien Dessenne <[email protected]>
Signed-off-by: Bjorn Andersson <[email protected]>

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hwspinlock: Remove redundant config

The hardware core can not be built as a module, so remove the redundant
CONFIG_HWSPINLOCK_MODULE config.

Signed-off-by: Baolin Wang <[email protected]>
Sign

hwspinlock: Remove redundant config

The hardware core can not be built as a module, so remove the redundant
CONFIG_HWSPINLOCK_MODULE config.

Signed-off-by: Baolin Wang <[email protected]>
Signed-off-by: Bjorn Andersson <[email protected]>

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hwspinlock: Add devm_xxx() APIs to register/unregister one hwlock controller

This patch introduces devm_hwspin_lock_register() and devm_hwspin_lock_unregister()
interfaces to help to register or unr

hwspinlock: Add devm_xxx() APIs to register/unregister one hwlock controller

This patch introduces devm_hwspin_lock_register() and devm_hwspin_lock_unregister()
interfaces to help to register or unregister one hardware spinlock controller, that
will help to simplify the cleanup code for hwspinlock drivers.

Signed-off-by: Baolin Wang <[email protected]>
Signed-off-by: Bjorn Andersson <[email protected]>

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hwspinlock: Add devm_xxx() APIs to request/free hwlock

This patch introduces some devm_xxx() APIs to help to request or free
the hwlocks, which will help to simplify the cleanup code for drivers
req

hwspinlock: Add devm_xxx() APIs to request/free hwlock

This patch introduces some devm_xxx() APIs to help to request or free
the hwlocks, which will help to simplify the cleanup code for drivers
requesting one hwlock, ensuring that the hwlock is automatically freed
whenever the device is unbound.

Signed-off-by: Baolin Wang <[email protected]>
Signed-off-by: Bjorn Andersson <[email protected]>

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hwspinlock: Add one new API to support getting a specific hwlock by the name

The hardware spinlock binding already supplied the 'hwlock-names' property
to match and get a specific hwlock, but did no

hwspinlock: Add one new API to support getting a specific hwlock by the name

The hardware spinlock binding already supplied the 'hwlock-names' property
to match and get a specific hwlock, but did not supply one API for users
to get a specific hwlock by the hwlock name. So this patch introduces one
API to support this requirement.

Signed-off-by: Baolin Wang <[email protected]>
Signed-off-by: Bjorn Andersson <[email protected]>

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hwspinlock/core: Switch to SPDX license identifier

Use the appropriate SPDX license identifier in the Hwspinlock core
driver source files and drop the previous boilerplate license text.

Signed-off-

hwspinlock/core: Switch to SPDX license identifier

Use the appropriate SPDX license identifier in the Hwspinlock core
driver source files and drop the previous boilerplate license text.

Signed-off-by: Suman Anna <[email protected]>
Signed-off-by: Bjorn Andersson <[email protected]>

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hwspinlock: Introduce one new mode for hwspinlock

In some scenarios, user need do some time-consuming or sleepable
operations under the hardware spinlock protection for synchronization
between the m

hwspinlock: Introduce one new mode for hwspinlock

In some scenarios, user need do some time-consuming or sleepable
operations under the hardware spinlock protection for synchronization
between the multiple subsystems.

For example, there is one PMIC efuse on Spreadtrum platform, which
need to be accessed under one hardware lock. But during the hardware
lock protection, the efuse operation is time-consuming to almost 5 ms,
so we can not disable the interrupts or preemption so long in this case.

Thus we can introduce one new mode to indicate that we just acquire the
hardware lock and do not disable interrupts or preemption, meanwhile we
should force user to protect the hardware lock with mutex or spinlock to
avoid dead-lock.

Signed-off-by: Baolin Wang <[email protected]>
Signed-off-by: Bjorn Andersson <[email protected]>

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hwspinlock/core: add device tree support

This patch adds a new OF-friendly API of_hwspin_lock_get_id()
for hwspinlock clients to use/request locks from a hwspinlock
device instantiated through a dev

hwspinlock/core: add device tree support

This patch adds a new OF-friendly API of_hwspin_lock_get_id()
for hwspinlock clients to use/request locks from a hwspinlock
device instantiated through a device-tree blob. This new API
can be used by hwspinlock clients to get the id for a specific
lock using the phandle + args specifier, so that it can be
requested using the available hwspin_lock_request_specific()
API.

Signed-off-by: Suman Anna <[email protected]>
Reviewed-by: Bjorn Andersson <[email protected]>
[small comment clarification]
Signed-off-by: Ohad Ben-Cohen <[email protected]>

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device.h: audit and cleanup users in main include dir

The <linux/device.h> header includes a lot of stuff, and
it in turn gets a lot of use just for the basic "struct device"
which appears so often.

device.h: audit and cleanup users in main include dir

The <linux/device.h> header includes a lot of stuff, and
it in turn gets a lot of use just for the basic "struct device"
which appears so often.

Clean up the users as follows:

1) For those headers only needing "struct device" as a pointer
in fcn args, replace the include with exactly that.

2) For headers not really using anything from device.h, simply
delete the include altogether.

3) For headers relying on getting device.h implicitly before
being included themselves, now explicitly include device.h

4) For files in which doing #1 or #2 uncovers an implicit
dependency on some other header, fix by explicitly adding
the required header(s).

Any C files that were implicitly relying on device.h to be
present have already been dealt with in advance.

Total removals from #1 and #2: 51. Total additions coming
from #3: 9. Total other implicit dependencies from #4: 7.

As of 3.3-rc1, there were 110, so a net removal of 42 gives
about a 38% reduction in device.h presence in include/*

Signed-off-by: Paul Gortmaker <[email protected]>

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hwspinlock: Don't return a value in __hwspin_unlock

Fix below build warning:

CC arch/arm/mach-omap2/hwspinlock.o
In file included from arch/arm/mach-omap2/hwspinlock.c:22:
include/linux/hwsp

hwspinlock: Don't return a value in __hwspin_unlock

Fix below build warning:

CC arch/arm/mach-omap2/hwspinlock.o
In file included from arch/arm/mach-omap2/hwspinlock.c:22:
include/linux/hwspinlock.h: In function '__hwspin_unlock':
include/linux/hwspinlock.h:121: warning: 'return' with a value, in function returning void

Signed-off-by: Axel Lin <[email protected]>
Signed-off-by: Ohad Ben-Cohen <[email protected]>

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hwspinlock/core: register a bank of hwspinlocks in a single API call

Hardware Spinlock devices usually contain numerous locks (known
devices today support between 32 to 256 locks).

Originally hwspi

hwspinlock/core: register a bank of hwspinlocks in a single API call

Hardware Spinlock devices usually contain numerous locks (known
devices today support between 32 to 256 locks).

Originally hwspinlock core required drivers to register (and later,
when needed, unregister) each lock separately.

That worked, but required hwspinlocks drivers to do a bit extra work
when they were probed/removed.

This patch changes hwspin_lock_{un}register() to allow a bank of
hwspinlocks to be {un}registered in a single invocation.

A new 'struct hwspinlock_device', which contains an array of 'struct
hwspinlock's is now being passed to the core upon registration (so
instead of wrapping each struct hwspinlock, a priv member has been added
to allow drivers to piggyback their private data with each hwspinlock).

While at it, several per-lock members were moved to be per-device:
1. struct device *dev
2. struct hwspinlock_ops *ops

In addition, now that the array of locks is handled by the core,
there's no reason to maintain a per-lock 'int id' member: the id of the
lock anyway equals to its index in the bank's array plus the bank's
base_id.
Remove this per-lock id member too, and instead use a simple pointers
arithmetic to derive it.

As a result of this change, hwspinlocks drivers are now simpler and smaller
(about %20 code reduction) and the memory footprint of the hwspinlock
framework is reduced.

Signed-off-by: Ohad Ben-Cohen <[email protected]>

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hwspinlock/core: remove stubs for register/unregister

hwspinlock drivers must anyway select CONFIG_HWSPINLOCK,
so there's no point in having register/unregister stubs.

Removing those stubs will onl

hwspinlock/core: remove stubs for register/unregister

hwspinlock drivers must anyway select CONFIG_HWSPINLOCK,
so there's no point in having register/unregister stubs.

Removing those stubs will only make it easier for developers
to catch CONFIG_HWSPINLOCK mis-.config-urations.

Signed-off-by: Ohad Ben-Cohen <[email protected]>

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hwspinlock/core/omap: fix id issues on multiple hwspinlock devices

hwspinlock devices provide system-wide hardware locks that are used
by remote processors that have no other way to achieve synchron

hwspinlock/core/omap: fix id issues on multiple hwspinlock devices

hwspinlock devices provide system-wide hardware locks that are used
by remote processors that have no other way to achieve synchronization.

To achieve that, each physical lock must have a system-wide id number
that is agreed upon, otherwise remote processors can't possibly assume
they're using the same hardware lock.

Usually boards have a single hwspinlock device, which provides several
hwspinlocks, and in this case, they can be trivially numbered 0 to
(num-of-locks - 1).

In case boards have several hwspinlocks devices, a different base id
should be used for each hwspinlock device (they can't all use 0 as
a starting id!).

While this is certainly not common, it's just plain wrong to just
silently use 0 as a base id whenever the hwspinlock driver is probed.

This patch provides a hwspinlock_pdata structure, that boards can use
to set a different base id for each of the hwspinlock devices they may
have, and demonstrates how to use it with the omap hwspinlock driver.

While we're at it, make sure the hwspinlock core prints an explicit
error message in case an hwspinlock is registered with an id number
that already exists; this will help users catch such base id issues.

Reported-by: Arnd Bergmann <[email protected]>
Signed-off-by: Ohad Ben-Cohen <[email protected]>
Acked-by: Tony Lindgren <[email protected]>

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drivers: hwspinlock: add framework

Add a platform-independent hwspinlock framework.

Hardware spinlock devices are needed, e.g., in order to access data
that is shared between remote processors, tha

drivers: hwspinlock: add framework

Add a platform-independent hwspinlock framework.

Hardware spinlock devices are needed, e.g., in order to access data
that is shared between remote processors, that otherwise have no
alternative mechanism to accomplish synchronization and mutual exclusion
operations.

Signed-off-by: Ohad Ben-Cohen <[email protected]>
Cc: Hari Kanigeri <[email protected]>
Cc: Benoit Cousson <[email protected]>
Cc: Kevin Hilman <[email protected]>
Cc: Grant Likely <[email protected]>
Cc: Paul Walmsley <[email protected]>
Cc: Russell King <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Signed-off-by: Tony Lindgren <[email protected]>

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