Namespaced the generated headers with `zephyr` to prevent
potential conflict with other headers.
Introduce a temporary Kconfig `LEGACY_GENERATED_INCLUDE_PATH`
that is enabled by default. This allows the developers to
continue the use of the old include paths for the time being
until it is deprecated and eventually removed. The Kconfig will
generate a build-time warning message, similar to the
`CONFIG_TIMER_RANDOM_GENERATOR`.
Updated the includes path of in-tree sources accordingly.
Most of the changes here are scripted, check the PR for more
info.
Signed-off-by: Yong Cong Sin <ycsin@meta.com>
Existing solutions for linking the Xtensa vector table are a
cut-and-paste mess of inherited code, with more than a dozen special
sections that need to be linked into many special MEMORY{} regions.
Accept the existing convention used by C/asm code, but automatically
detect the needed offsets for the platform from core-isa.h (it can
share the preprocessing with gen_zsr.py) and emit a file that can be
included in lieu of all the existing boilerplate.
Signed-off-by: Andy Ross <andyross@google.com>
The script to generate the _soc_inthandlers.h header has been run
manually for years, only because I was a cmake novice at the time and
unsure how to integrate it into the build. So every new platform has
to find the script and template file and figure out how to generate
the file. And in a few cases it looks like we've tried to EDIT the
resulting files in the tree.
Let's finally do this right. The file is now dropped (for every
xtensa platform) as a "xtensa_handlers.h" file, and there is a Kconfig
to control whether the original/manual file or the new one is used by
the platform code. We can migrate the other platforms slowly as
people have time to validate.
Signed-off-by: Andy Ross <andyross@google.com>
For CPU without THREADPTR, we need an alternative way to figure
out if we are in user context. This extends the user context
check to do that via a brief syscall.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Adds the necessary code required to unconditionally save/restore the
HiFi AE registers. The macros xchal_cp1_load and xchal_cp1_store
are defined in the Xtensa HAL.
Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
The ZSR_FLUSH scratch register is only needed if kconfig
CONFIG_KERNEL_COHERENCE is enabled. So update gen_zsr.py
for that.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Rename xtensa_asm2.c to have a more meaningful name to actually
reflect the content of the file. This file is mostly about
handling interrupts and exceptions (via the predefined vectors
in Xtensa core).
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Header files under arch/xtensa/include are considered internal
to architecture. There is really no need for two places to
house architecture internal header files.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
... from xtensa_asm2.c.
Everything has been stuffed inside xtensa_asm2.c where
they are all mangled together. So extract thread related
stuff into its own file.
Note that arch_float_*() may not be thread related but
most other architectures put them into thread.c. So we
also do it here.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
arch_spin_relax() does not really fit into the scheme of
xtensa_asm2.c as it is mainly about handling interrupts
and exceptions. So move it into smp.c, similar to other
architectures which arch_spin_relax() defined.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Simply to provide some consistencies on file naming under
arch/xtensa.
These are all internally used files and are not public.
So there is no need to provide a deprecation path for
them.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Add support for relocating local symbols, as specified in the
.rela.dyn section.
Signed-off-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Andy Ross re-implementation of MMU layer with some subtle changes,
like re-using existent macros, fix page table cache property when
direct mapping it in TLB.
From Andy's original commit message:
This is a reworked MMU layer, sitting cleanly below the page table
handling in the OS. Notable differences from the original work:
+ Significantly smaller code and simpler API (just three functions to
be called from the OS/userspace/ptable layer).
+ Big README-MMU document containing my learnings over the process, so
hopefully fewer people need to go through this in the future.
+ No TLB flushing needed. Clean separation of ASIDs, just requires
that the upper levels match the ASID to the L1 page table page
consistently.
+ Vector mapping is done with a 4k page and not a 4M page, leading to
much more flexibility with hardware memory layout. The original
scheme required that the 4M region containing vecbase be mapped
virtually to a location other than the hardware address, which makes
confusing linkage with call0 and difficult initialization
constraints where the exception vectors run at different addresses
before and after MMU setup (effectively forcing them to be PIC
code).
+ More provably correct initialization, all MMU changes happen in a
single asm block with no memory accesses which would generate a
refill.
Signed-off-by: Andy Ross <andyross@google.com>
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
When MMU is enabled, we need some scratch registers to preload
page table entries. So update gen_zsr.py to that.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Userspace support for Xtensa architecture using Xtensa MMU.
Some considerations:
- Syscalls are not inline functions like in other architectures because
some compiler issues when using multiple registers to pass parameters
to the syscall. So here we have a function call so we can use
registers as we need.
- TLS is not supported by xcc in xtensa and reading PS register is
a privileged instruction. So, we have to use threadptr to know if a
thread is an user mode thread.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
This provides custom memory range check functions as
it gets a bit complicated with cached/uncached regions.
These functions are marked as __weak so SoC or board
can override these if needed.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Initial support for Xtensa MMU version 3. It is using a two level page
table based on fact that the page table is in the virtual space. Only
the top level (page directory) is wired mapped in the TLB to avoid
second level page miss.
The mapped memory is completely fragmented in multiple sections, maybe
we find a better way in future.
The exception handler is where we effectively map the memory, the way it
works is:
1) SW try to access some memory address
2) The address is not mapped, so the MMU will try the auto-refill,
looking the page table
3) The page table contents is not mapped (remember, just the top-level page
is mapped)
4) An exception will be triggered, in the exception we try to read the
portion of the page table that maps the original address
5) The address is not mapped, so the MMU will try again the auto-refill.
This time though, the address is mapped by the top level page that is
properly mapped. (The top-level page maps the page table itself).
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Expose the Xtenesa CCOUNT timing register (the lowest level CPU cycle
counter) using the arch_timing_*() API.
This is the simplest possible way to get this working. Future work
might focus on moving the rate configuration into devicetree in a
standard way, integrating with the platform clock driver on intel_adsp
such that the reported cycle rate tracks runtime changes (though IIRC
this is not a SOF requirement), and adding better test coverage to the
timing layer, which right now isn't exercised anywhere but in
benchmarks.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Some XCC toolchains do not provide atexit() which results
in undefined reference error. So add a weak dummy atexit()
for this siutation.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Turns out that xt-xcc will bail when faced with a real core-isa.h (it
wants you to rely on the builtins in the compiler). Undefine __XCC__
to force it to actually parse and emit declarations for its own
header.
(Also adds a newline to the generated one-line C file to silence a warning)
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Zephyr likes to use the various Xtensa scratch registers for its own
purposes in several places. Unfortunately, owing to the
configurability of the architecture, we have to use different
registers for different platforms. This has been done so far with a
collection of different tricks, some... less elegant than others.
Put it all in one place. This is a python script that emites a
"zsr.h" header with register assignments for all the existing users.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Adds Xtensa as supported architecture for coredump. Fixes
a few typos in documentation, Kconfig and a C file. Dumps
minimal set of registers shown by 'info registers' in GDB
for the sample_controller and ESP32 SOCs. Updates tests.
Signed-off-by: Lauren Murphy <lauren.murphy@intel.com>
This adds basic support for GDB stub on Xtensa. Note that
this only provides the common bits on the architecture side.
SoC support is also required to fully enable GDB stub on
each Xtensa SoC.
Signed-off-by: Daniel Leung <daniel.leung@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 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>
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>
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>
We re-wrote the xtensa arch code, but never got around
to purging the old implementation.
Removed those boards which hadn't been moved to the new
arch code. These were all xt-sim simulator targets and not
real hardware.
Fixes: #18138
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Update the files which contain no license information with the
'Apache-2.0' SPDX license identifier. 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 Zephyr, which is Apache version 2.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Non-asm2 devices without a generated SoC interrupt file will see a
compile failure due to the missing header.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The asm2 layer will build alongside the traditional assembly, but the
reverse is not true. Add a CONFIG_XTENSA_ASM2 to force its use at
runtime and disable the older code.
Note that the older assembly had an initialization function that is
properly part of the timer driver. Move a C equivalent into the timer
driver itself for now to prevent a build breakage. Long term we need
to clean that driver up in a bunch of other ways.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
SMP needs a new context switch primitive (to disentangle _swap() from
the scheduler) and new interrupt entry behavior (to be able to take a
global spinlock on behalf of legacy drivers). The existing code is
very obtuse, and working with it led me down a long path of "this
would be so much better if..." So this is a new context and entry
framework, intended to replace the code that exists now, at least on
SMP platforms.
New features:
* The new context switch primitive is xtensa_switch(), which takes a
"new" context handle as an argument instead of getting it from the
scheduler, returns an "old" context handle through a pointer
(e.g. to save it to the old thread context), and restores the lock
state(PS register) exactly as it is at entry instead of taking it as
an argument.
* The register spill code understands wrap-around register windows and
can avoid spilling A4-A15 registers when they are unused by the
interrupted function, saving as much as 48 bytes of stack space on
the interrupted stacks.
* The "spill register windows" routine is entirely different, using a
different mechanism, and is MUCH FASTER (to the tune of almost 200
cycles). See notes in comments.
* Even better, interrupt entry can be done via a clever "cross stack
call" I worked up, meaning that the interrupted thread's registers
do not need to be spilled at all until they are naturally pushed out
by the interrupt handler or until we return from the interrupt into
a different thread. This is a big efficiency win for tiny
interrupts (e.g. timers), and a big latency win for all interrupts.
* Interrupt entry is 100% symmetric with respect to medium/high
interrupts, avoiding the problems seen with hooking high priority
interrupts with the current code (e.g. ESP-32's watchdog driver).
* Much smaller code size. No cut and paste assembly. No use of HAL
calls.
* Assumes "XEA2" interrupt architecture, the register window extension
(i.e. no CALL0 ABI), and the "high priority interrupts" extension.
Does not support the legacy processor variants for which we have no
targets. The old code has some stuff in there to support this, but
it seems bitrotten, untestable, and I'm all but certain it doesn't
work.
Note that this simply adds the primitives to the existing tree in a
form where they can be unit tested. It does not replace the existing
interrupt/exception handling or _Swap() implementation.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Introducing CMake is an important step in a larger effort to make
Zephyr easy to use for application developers working on different
platforms with different development environment needs.
Simplified, this change retains Kconfig as-is, and replaces all
Makefiles with CMakeLists.txt. The DSL-like Make language that KBuild
offers is replaced by a set of CMake extentions. These extentions have
either provided simple one-to-one translations of KBuild features or
introduced new concepts that replace KBuild concepts.
This is a breaking change for existing test infrastructure and build
scripts that are maintained out-of-tree. But for FW itself, no porting
should be necessary.
For users that just want to continue their work with minimal
disruption the following should suffice:
Install CMake 3.8.2+
Port any out-of-tree Makefiles to CMake.
Learn the absolute minimum about the new command line interface:
$ cd samples/hello_world
$ mkdir build && cd build
$ cmake -DBOARD=nrf52_pca10040 ..
$ cd build
$ make
PR: zephyrproject-rtos#4692
docs: http://docs.zephyrproject.org/getting_started/getting_started.html
Signed-off-by: Sebastian Boe <sebastian.boe@nordicsemi.no>