The kernel passes the CPU's interrupt stack expected that it will
start on that, so do it. Pass the initial stack pointer from the SOC
layer in the variable "z_mp_stack_top" and set it in the assembly
startup before calling z_mp_entry().
Signed-off-by: Andy Ross <andrew.j.ross@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>
There was a bunch of dead historical cruft floating around in the
arch/xtensa tree, left over from older code versions. It's time to do
a cleanup pass. This is entirely refactoring and size optimization,
no behavior changes on any in-tree devices should be present.
Among the more notable changes:
+ xtensa_context.h offered an elaborate API to deal with a stack frame
and context layout that we no longer use.
+ xtensa_rtos.h was entirely dead code
+ xtensa_timer.h was a parallel abstraction layer implementing in the
architecture layer what we're already doing in our timer driver.
+ The architecture thread structs (_callee_saved and _thread_arch)
aren't used by current code, and had dead fields that were removed.
Unfortunately for standards compliance and C++ compatibility it's
not possible to leave an empty struct here, so they have a single
byte field.
+ xtensa_api.h was really just some interrupt management inlines used
by irq.h, so fold that code into the outer header.
+ Remove the stale assembly offsets. This architecture doesn't use
that facility.
All told, more than a thousand lines have been removed. Not bad.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
a0 is used as scratch register. Restore value of a0 (return address)
from stack frame before spilling registers on stack
Signed-off-by: Shubham Kulkarni <shubham.kulkarni@espressif.com>
Only the CAVS 1.5 linker script has full support for the coherence
features, don't advertise it on the other SoC's yet.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
While fixing license headers, identified this script as orphan and not
being used anywhere, so remove.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
XCC doesn't like the "rsr.<reg name>" style assembly
so fix that to the other style.
Also, XCC doesn't like _CONCAT() with the EPC/EPS
registers so need to spell out all of them.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
There is a hard-coded value of PS_INTLEVEL(15) to set the PS
register. The correct way is actually to use XCHAL_EXCM_LEVEL
with PS_INTLEVEL() to setup the register. So fix it.
Fixes#31858
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
This change uses stack frame to print backtrace once exception occurs
Printing backtrace helps to identify the cause of exception
Signed-off-by: Shubham Kulkarni <shubham.kulkarni@espressif.com>
Currently Zephyr links reset-vector.S twice in xtensa builds:
into the bootloader and the main image. It is run at the end
of the boot loader execution and immediately after that again
in the beginning of the main code. This patch adds a
configuration option to select whether to link the file to the
bootloader or to the application. The default is to the
application, as needed e.g. for QEMU, SOF links it to the
bootloader like in native builds.
Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
There may be Xtensa SoCs which don't have high enough interrupt
levels for EPC6/EPS6 to exist in _restore_context. So changes
these to those which should be available according to the ISA
config file.
Fixes#30126
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Most of kernel files where declaring os module without providing
log level. Because of that default log level was used instead of
CONFIG_KERNEL_LOG_LEVEL.
Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
Since the tracing of thread being switched in/out has the same
instrumentation points, we can roll the tracing function calls
into the one for thread stats gathering functions.
This avoids duplicating code to call another function.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Adds the necessary bits to initialize TLS in the stack
area and sets up CPU registers during context switch.
Note that this does not enable TLS for all Xtensa SoC.
This is because Xtensa SoCs are highly configurable
so that each SoC can be considered a whole architecture.
So TLS needs to be enabled on the SoC level, instead of
at the arch level.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Implement the kernel "coherence" API on top of the linker
cached/uncached mapping work.
Add Xtensa handling for the stack coherence API.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
It's legal to have CONFIG_MP_NUM_CPUS > 1 and !CONFIG_SMP. The
tests/kernel/mp test does this as a unit test of the multiprocessor
facilities. Test the right tunable when deciding whether to blow away
static data or not.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
This code had one purpose only, feed timing information into a test and
was not used by anything else. The custom trace points unfortunatly were
not accurate and this test was delivering informatin that conflicted
with other tests we have due to placement of such trace points in the
architecture and kernel code.
For such measurements we are planning to use the tracing functionality
in a special mode that would be used for metrics without polluting the
architecture and kernel code with additional tracing and timing code.
Furthermore, much of the assembly code used had issues.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Move tracing switched_in and switched_out to the architecture code and
remove duplications. This changes swap tracing for x86, xtensa.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
The core kernel computes the initial stack pointer
for a thread, properly aligning it and subtracting out
any random offsets or thread-local storage areas.
arch_new_thread() no longer needs to make any calculations,
an initial stack frame may be placed at the bounds of
the new 'stack_ptr' parameter passed in. This parameter
replaces 'stack_size'.
thread->stack_info is now set before arch_new_thread()
is invoked, z_new_thread_init() has been removed.
The values populated may need to be adjusted on arches
which carve-out MPU guard space from the actual stack
buffer.
thread->stack_info now has a new member 'delta' which
indicates any offset applied for TLS or random offset.
It's used so the calculations don't need to be repeated
if the thread later drops to user mode.
CONFIG_INIT_STACKS logic is now performed inside
z_setup_new_thread(), before arch_new_thread() is called.
thread->stack_info is now defined as the canonical
user-accessible area within the stack object, including
random offsets and TLS. It will never include any
carved-out memory for MPU guards and must be updated at
runtime if guards are removed.
Available stack space is now optimized. Some arches may
need to significantly round up the buffer size to account
for page-level granularity or MPU power-of-two requirements.
This space is now accounted for and used by virtue of
the Z_THREAD_STACK_SIZE_ADJUST() call in z_setup_new_thread.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
MISRA-C wants the parameter names in a function implementaion
to match the names used by the header prototype.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
arch_new_thread() passes along the thread priority and option
flags, but these are already initialized in thread->base and
can be accessed there if needed.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
This operation is formally defined as rounding down a potential
stack pointer value to meet CPU and ABI requirments.
This was previously defined ad-hoc as STACK_ROUND_DOWN().
A new architecture constant ARCH_STACK_PTR_ALIGN is added.
Z_STACK_PTR_ALIGN() is defined in terms of it. This used to
be inconsistently specified as STACK_ALIGN or STACK_PTR_ALIGN;
in the latter case, STACK_ALIGN meant something else, typically
a required alignment for the base of a stack buffer.
STACK_ROUND_UP() only used in practice by Risc-V, delete
elsewhere.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
The core kernel z_setup_new_thread() calls into arch_new_thread(),
which calls back into the core kernel via z_new_thread_init().
Move everything that doesn't have to be in z_new_thread_init() to
z_setup_new_thread() and convert to an inline function.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Under multi-processing, only the first CPU#0 needs to go through
setting up the kernel structs and clearing out BSS (among others).
There is no need for other CPUs to do those tasks. Since each
Xtensa core starts using the same boot vector, CPUs other than #0
need to skip all the startup tasks by not calling to z_cstart().
So provide another entry point for those CPUs. Note that Xtensa
arch is highly configurable. So the implementation of the entry
point is up to each individual SoC config.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Under SMP, the main BSS section only needs to be zero-ed on CPU #0.
Other CPUs should not zero out BSS, or else it may cause CPU #0 to
crash on invalid data.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
The set of interrupt stacks is now expressed as an array. We
also define the idle threads and their associated stacks this
way. This allows for iteration in cases where we have multiple
CPUs.
There is now a centralized declaration in kernel_internal.h.
On uniprocessor systems, z_interrupt_stacks has one element
and can be used in the same way as _interrupt_stack.
The IRQ stack for CPU 0 is now set in init.c instead of in
arch code.
The extern definition of the main thread stack is now removed,
this doesn't need to be in a header.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Xtensa uses two instructions to perform atomic compare-and-set
instruction: first the comparison register, then the actual
instruction to do compare-and-set. There is a potential that
context switching is performed before these two instructions.
A restored context may have the wrong value in the comparison
register. So we need to save and restore the comparison
register during context switching.
Fixes#21800
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
This reverts commit 9987c2e2f9
which spills SoC configs into architecture files and is not
exactly desirable. So revert it.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Use BOOTLOADER definition to separate bootloader code. This allows to
use the same file reset-vector.S when building bootloader and when
CONFIG_XTENSA_RESET_VECTOR is enabled.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
The atomic_cas function was using incorrect register when determining
whether value was swapped. The swapping instruction s32c1i in
atomic_cas stores the value at memory location in register a4
regardless of whether swapping is done. In this case, the register a4
should be used to determine whether a swap is done. However, register
a3 (containing the oldValue as function argument) is used instead.
Since register a5 contains the old value at address loaded before
the swapping instruction, a3 and a5 contain the same value.
Since a3 == a5 is always true in this case, the function will always
return 1 even though values are not swapped. So fix it by using
the correct register.
Also, in case the value is not swapped, it jumps to where it returns
zero instead of loading from memory and comparing again.
The function was simply looping until swapping was done, which did not
align with the API where it would return 0 when swapping is not done
(regardless whether the memory location contains the old value or not).
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
This adds the necessary bits to build the Xtensa HAL as
a module, and removes the bits to use the HAL built with
the Zephyr SDK.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Promote the private z_arch_* namespace, which specifies
the interface between the core kernel and the
architecture code, to a new top-level namespace named
arch_*.
This allows our documentation generation to create
online documentation for this set of interfaces,
and this set of interfaces is worth treating in a
more formal way anyway.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
When compiling the components under the arch directory, the compiler
include paths for arch and kernel private headers need to be specified.
This was previously done by adding 'zephyr_library_include_directories'
to CMakeLists.txt file for every component under the arch directory,
and this resulted in a significant amount of duplicate code.
This commit uses the CMake 'include_directories' command in the root
CMakeLists.txt to simplify specification of the private header include
paths for all the arch components.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This commit refactors kernel and arch headers to establish a boundary
between private and public interface headers.
The refactoring strategy used in this commit is detailed in the issue
This commit introduces the following major changes:
1. Establish a clear boundary between private and public headers by
removing "kernel/include" and "arch/*/include" from the global
include paths. Ideally, only kernel/ and arch/*/ source files should
reference the headers in these directories. If these headers must be
used by a component, these include paths shall be manually added to
the CMakeLists.txt file of the component. This is intended to
discourage applications from including private kernel and arch
headers either knowingly and unknowingly.
- kernel/include/ (PRIVATE)
This directory contains the private headers that provide private
kernel definitions which should not be visible outside the kernel
and arch source code. All public kernel definitions must be added
to an appropriate header located under include/.
- arch/*/include/ (PRIVATE)
This directory contains the private headers that provide private
architecture-specific definitions which should not be visible
outside the arch and kernel source code. All public architecture-
specific definitions must be added to an appropriate header located
under include/arch/*/.
- include/ AND include/sys/ (PUBLIC)
This directory contains the public headers that provide public
kernel definitions which can be referenced by both kernel and
application code.
- include/arch/*/ (PUBLIC)
This directory contains the public headers that provide public
architecture-specific definitions which can be referenced by both
kernel and application code.
2. Split arch_interface.h into "kernel-to-arch interface" and "public
arch interface" divisions.
- kernel/include/kernel_arch_interface.h
* provides private "kernel-to-arch interface" definition.
* includes arch/*/include/kernel_arch_func.h to ensure that the
interface function implementations are always available.
* includes sys/arch_interface.h so that public arch interface
definitions are automatically included when including this file.
- arch/*/include/kernel_arch_func.h
* provides architecture-specific "kernel-to-arch interface"
implementation.
* only the functions that will be used in kernel and arch source
files are defined here.
- include/sys/arch_interface.h
* provides "public arch interface" definition.
* includes include/arch/arch_inlines.h to ensure that the
architecture-specific public inline interface function
implementations are always available.
- include/arch/arch_inlines.h
* includes architecture-specific arch_inlines.h in
include/arch/*/arch_inline.h.
- include/arch/*/arch_inline.h
* provides architecture-specific "public arch interface" inline
function implementation.
* supersedes include/sys/arch_inline.h.
3. Refactor kernel and the existing architecture implementations.
- Remove circular dependency of kernel and arch headers. The
following general rules should be observed:
* Never include any private headers from public headers
* Never include kernel_internal.h in kernel_arch_data.h
* Always include kernel_arch_data.h from kernel_arch_func.h
* Never include kernel.h from kernel_struct.h either directly or
indirectly. Only add the kernel structures that must be referenced
from public arch headers in this file.
- Relocate syscall_handler.h to include/ so it can be used in the
public code. This is necessary because many user-mode public codes
reference the functions defined in this header.
- Relocate kernel_arch_thread.h to include/arch/*/thread.h. This is
necessary to provide architecture-specific thread definition for
'struct k_thread' in kernel.h.
- Remove any private header dependencies from public headers using
the following methods:
* If dependency is not required, simply omit
* If dependency is required,
- Relocate a portion of the required dependencies from the
private header to an appropriate public header OR
- Relocate the required private header to make it public.
This commit supersedes #20047, addresses #19666, and fixes#3056.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
Use this short header style in all Kconfig files:
# <description>
# <copyright>
# <license>
...
Also change all <description>s from
# Kconfig[.extension] - Foo-related options
to just
# Foo-related options
It's clear enough that it's about Kconfig.
The <description> cleanup was done with this command, along with some
manual cleanup (big letter at the start, etc.)
git ls-files '*Kconfig*' | \
xargs sed -i -E '1 s/#\s*Kconfig[\w.-]*\s*-\s*/# /'
Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>
Same deal as in commit 7fdb525754 ("kconfig: Use 'default' instead of
'def_bool' in Kconfig.defconfig files"), but I hacked Kconfiglib to also
find cases where the type is given separately as e.g.
config FOO
int
default 3
Motivation (from a note in
https://docs.zephyrproject.org/latest/guides/kconfig/index.html):
For a symbol defined in multiple locations (e.g., in a
Kconfig.defconfig file in Zephyr), it is best to only give the
symbol type for the "base" definition of the symbol, and to use
'default' (instead of 'def_<type>' value) for the remaining
definitions. That way, if the base definition of the symbol is
removed, the symbol ends up without a type, which generates a
warning that points to the other definitions. That makes the extra
definitions easier to discover and remove.
It's also nice if 'def_bool' and the like turn into a semi-reliable flag
that the symbol is only defined in Kconfig.defconfig files. That might
be a sign that things could be cleaned up.
Will do a separate pass later to remove some symbols only defined in
Kconfig.defconfig files.
Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>
Unused since commit 6fd6b7e50a ("xtensa: remove legacy arch
implementation").
Found with a script.
Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>
Unused since commit 6fd6b7e50a ("xtensa: remove legacy arch
implementation").
Found with a script.
Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>
include/sys/arch_inlines.h will contain all architecture APIs
that are used by public inline functions and macros,
with implementations deriving from include/arch/cpu.h.
kernel/include/arch_interface.h will contain everything
else, with implementations deriving from
arch/*/include/kernel_arch_func.h.
Instances of duplicate documentation for these APIs have been
removed; implementation details have been left in place.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
