By redefining `atomic_t` as `long`, the type is 32-bit on
32-bit architectures and 64-bit on 64-bit architectures.
Signed-off-by: Christopher Friedt <chrisfriedt@gmail.com>
Makes miscellaneous fixes to kernel and usermode documentation,
such as fixing broken links and adding clarifying wording.
Signed-off-by: Lauren Murphy <lauren.murphy@intel.com>
Some Kconfig options are left marked as inline literals. But in
Zephyr document, we use the "kconfig" role provided by Sphinx.
Signed-off-by: Yasushi SHOJI <yashi@spacecubics.com>
Updates CXX support documentation to reflect exception support
added in fixes for #32448 and #35772.
Signed-off-by: Lauren Murphy <lauren.murphy@intel.com>
Contrary to the documentation giving a semaphore while an IRQ lock is
held does not release the lock and give control to another thread.
The release-lock behavior is observed only if the lock-holding thread
sleeps.
However the opportunity to reschedule will have been lost so it may be
necessary to explicitly yield to allow the higher-priority thread to
be serviced.
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
This adds FPU sharing support with a lazy context switching algorithm.
Every thread is allowed to use FPU/SIMD registers. In fact, the compiler
may insert FPU reg accesses in anycontext to optimize even non-FP code
unless the -mgeneral-regs-only compiler flag is used, but Zephyr
currently doesn't support such a build.
It is therefore possible to do FP access in IRS as well with this patch
although IRQs are then disabled to prevent nested IRQs in such cases.
Because the thread object grows in size, some tests have to be adjusted.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Move out of misc/ and put in own folder and add the grouping to doxygen
to be able to reference the doxygen docs into RST.
Move each item into their own file to reduce clutter and to make it
less crowded in one single page.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
The xtensa atomics layer was written with hand-coded assembly that had
to be called as functions. That's needlessly slow, given that the low
level primitives are a two-instruction sequence. Ideally the compiler
should see this as an inline to permit it to better optimize around
the needed barriers.
There was also a bug with the atomic_cas function, which had a loop
internally instead of returning the old value synchronously on a
failed swap. That's benign right now because our existing spin lock
does nothing but retry it in a tight loop anyway, but it's incorrect
per spec and would have caused a contention hang with more elaborate
algorithms (for example a spinlock with backoff semantics).
Remove the old implementation and replace with a much smaller inline C
one based on just two assembly primitives.
This patch also contains a little bit of refactoring to address the
scheme has been split out into a separate header for each, and the
ATOMIC_OPERATIONS_CUSTOM kconfig has been renamed to
ATOMIC_OPERATIONS_ARCH to better capture what it means.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
This adds X86 keyword to the kconfigs to indicate these are
for x86. The old options are still there marked as
deprecated.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Update the documentation for Lazy Stacking in Cortex-M, to
reflect the functionality changes (activate the lazy stacking
dynamically when building with MPU stack guards).
Make a note that the FP sharing mode is now default in Cortex-M.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
This change adds full shared floating point support for the SPARC
architecture.
All SPARC floating point registers are scratch registers with respect
to function call boundaries. That means we only have to save floating
point registers when switching threads in ISR. The registers are
stored to the corresponding thread stack.
FPU is disabled when calling ISR. Any attempt to use FPU in ISR
will generate the fp_disabled trap which causes Zephyr fatal error.
- This commit adds no new thread state.
- All FPU contest save/restore is synchronous and lazy FPU context
switch is not implemented.
Signed-off-by: Martin Åberg <martin.aberg@gaisler.com>
Clarify that while any number of kernel objects can be created, there is
a limit which is set by the available RAM.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Previously, ring buffer had capacity of provided buffer size - 1. This
trick was used to distinguish between empty and full states. It had one
drawback: ring buffer could not be used as a pool of equal sized buffers
(using ring_buf_put_claim and ring_buf_get_claim).
Reworked internals to use non wrapping head and tail. Since they are
non wrapping, there is no issue with distinguishing between empty and
full. Since this appraoch would be vulnerable to wrapping on 32 bit
boundary, added a mechanism which periodically reduces all indexes to
avoid 32 bit wrapping.
After this rework, buffer has one byte more capacity. Simple test shows
slight performance improvement.
Updated tests to reflect increased capacity and added test to check if
it is possible to continuesly allocated 2 buffers of half ring buffer
size.
Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
Add description how to enable zero-latency interrupt in the application
code. Previous docs described only the Kconfig and not the flag.
Signed-off-by: Martin Jäger <martin@libre.solar>
Some macros were using :c:func: and :cpp:func: which forbids Breathe
from resolving those symbols. Update to :c:macro: for proper resolution.
Signed-off-by: Fabio Utzig <fabio.utzig@nordicsemi.no>
Sphinx>=3.0 includes the `struct` role in the C domain, which provides a
specific way to link to structs, while the old :c:type: role should be
primary used to typedefs. Update existing references, using :c:type:,
:cpp:type: or emphasized symbols that point to structs to use the new
role.
Signed-off-by: Fabio Utzig <fabio.utzig@nordicsemi.no>
Following the change to use the C domain for parsing, update all
existing :cpp:func: references to :c:func:. Remove the parentheses as
well, if used, because they are not needed, this is already known to be
a function, and how it is displayed in the documentation later is a
semantic decision done by the output builder.
Signed-off-by: Fabio Utzig <fabio.utzig@nordicsemi.no>
Fixing issues with recent versions of breathe 4.19.2:
WARNING: Unparseable C cross-reference: 'struct device'
Invalid C declaration: Expected identifier in nested name, got keyword:
struct [error at 6]
struct device
------^
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
This commit renames the Kconfig `FP_SHARING` symbol to `FPU_SHARING`,
since this symbol specifically refers to the hardware FPU sharing
support by means of FPU context preservation, and the "FP" prefix is
not fully descriptive of that; leaving room for ambiguity.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This commit renames the Kconfig `FLOAT` symbol to `FPU`, since this
symbol only indicates that the hardware Floating Point Unit (FPU) is
used and does not imply and/or indicate the general availability of
toolchain-level floating point support (i.e. this symbol is not
selected when building for an FPU-less platform that supports floating
point operations through the toolchain-provided software floating point
library).
Moreover, given that the symbol that indicates the availability of FPU
is named `CPU_HAS_FPU`, it only makes sense to use "FPU" in the name of
the symbol that enables the FPU.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This change adds full shared floating point support for the RISCV
architecture with minimal impact on threads with floating point
support not enabled.
Signed-off-by: Corey Wharton <coreyw7@fb.com>
k_poll() for a signal is often desired for notification of completion
of asynchronous operations, but there are APIs where it may be
necessary to invoke "asynchronous" operations from contexts where
sleep is disallowed, or before the kernel has been initialized.
Extract the general notification solution from the on-off service into
a utility that can be used for other APIs.
Also move documentation out to a resource management section.
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
In order to de-duplicate 2 macros with the same use,
merge BUILD_ASSERT(), BUILD_ASSERT_MSG() into one macro.
Make BUILD_ASSERT_MSG() deprecated.
Signed-off-by: Oleg Zhurakivskyy <oleg.zhurakivskyy@intel.com>
k_cpu_idle() API does not need to be invoked with interrupts
unlocked; it is actually invoked with interrupts locked by
the kernel CPU idling mechanism. In most architectures, the
function is, actually, un-locking interrupts itself. We need
to remove this comment from the documentation of the CPU
idle API. We add a note about the un-locking of interrupts.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
This reverts commit 974aa3add4.
Pull Request #23437 was merged by mistake with an invalid manifest.
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>
In order to de-duplicate 2 macros with the same use,
merge BUILD_ASSERT(), BUILD_ASSERT_MSG() into one macro.
Make BUILD_ASSERT_MSG() deprecated.
Signed-off-by: Oleg Zhurakivskyy <oleg.zhurakivskyy@intel.com>
Add detailed documentation for macros that get generated by
gen_defines.py. Covers properties, interrupts, phandle-arrays, clocks,
buses, flash partitions, SPI, etc.
Should be relatively complete now, though there might be overlooked
details.
Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>
Co-Authored-By: Kumar Gala <kumar.gala@linaro.org>
Co-Authored-By: Marti Bolivar <marti.bolivar@nordicsemi.no>
There are various situations where it's necessary to support turning
devices on or off at runtime, includin power rails, clocks, other
peripherals, and binary device power management. The complexity of
properly managing multiple consumers of a device in a multithreaded
system suggests that a shared implementation is desirable. This
commit provides an API that supports managing on-off resources.
Signed-off-by: Peter A. Bigot <pab@pabigot.com>
Add a simple documentation section for the Zero-Latency
IRQs feature supported by the kernel.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
Document that the Dynamic Direct interrupts feature is
implemented and supported as an ARM-only API.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
We have a collection of python scripts that are part of our build
system. This PR collects docstring comments added to these scripts into
a summary document. Previous references to just the script name in
other documentation are updated to point to this build tool
documentation.
Some of the scripts needed an update to be processed (via include
directives) consistently.
Signed-off-by: David B. Kinder <david.b.kinder@intel.com>
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Remove leading/trailing blank lines in .c, .h, .py, .rst, .yml, and
.yaml files.
Will avoid failures with the new CI test in
https://github.com/zephyrproject-rtos/ci-tools/pull/112, though it only
checks changed files.
Move the 'target-notes' target in boards/xtensa/odroid_go/doc/index.rst
to get rid of the trailing blank line there. It was probably misplaced.
Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>
We don't really have docs on how fatal errors are induced
or handled. Provide some documentation that covers:
- Assertions (runtime and build)
- Kernel panic and oops conditions
- Stack overflows
- Other exceptions
- Exception handling policy
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
This commit adds a short note in reference/kernel/other/float.
The note instructs to apply pre-tagging of ARM threads to
indicate that they indend to use the FP services.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
The Quark D2000 is the only x86 with an MVIC, and since support for
it has been dropped, the interrupt controller is orphaned. Removed.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
This commit rewrites the documentation section describing
the Shared FP registers mode for Cortex-M to align with the
latest architecture rework of Shared FP mode.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
This commit removes the activation of the FP context
in ARM system boot. There is no need to do this, since
the FP context will be activated in the presence of
floating point instructions. We update the reference
documentation accordingly.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
This commit updates the documentation as follows:
- stresses that the lazy stacking preservation is disabled
by default and not supported in ARM Cortex-M builds,
- corrects the figure of extra stack requirement when
floating point services are enabled in ARM builds.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
This commit provides the following fixes:
- Corrects the note regarding which ARM MCUs may support
floating point services
- Rewords the text stressing the undefined behavior when
multiple threads access the floating point registers.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
