Move common SoC dts.fixup defines into
arch/arm/soc/atmel_sam/<BAR>/dts.fixup so we remove duplication in the
boards and only have board specific defines in
boards/arm/<FOO>/dts.fixup.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Move common SoC dts.fixup defines into arch/arm/soc/nxp_imx/rt/dts.fixup
so we remove duplication in the boards and only have board specific
defines in boards/arm/<FOO>/dts.fixup.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Move common SoC dts.fixup defines into
arch/arm/soc/nxp_kinetis/kwx/dts.fixup so we remove duplication in
the boards and only have board specific defines in
boards/arm/<FOO>/dts.fixup.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Move common SoC dts.fixup defines into
arch/arm/soc/nxp_kinetis/kl2x/dts.fixup so we remove duplication in
the boards and only have board specific defines in
boards/arm/<FOO>/dts.fixup.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Move common SoC dts.fixup defines into
arch/arm/soc/nxp_lpc/lpc54xxx/dts.fixup so we remove duplication in
the boards and only have board specific defines in
boards/arm/<FOO>/dts.fixup.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Move common SoC dts.fixup defines into
arch/arm/soc/nxp_kinetis/k6x/dts.fixup so we remove duplication in the
boards and only have board specific defines in
boards/arm/<FOO>/dts.fixup.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Move common SoC dts.fixup defines into
arch/arm/soc/ti_simplelink/<BAR>/dts.fixup so we remove duplication in
the boards and only have board specific defines in
boards/arm/<FOO>/dts.fixup.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Include `soc.h` first, which will include the ESP-IDF headers -- which
will define the `BIT()` macro without checking if they're already
defined, like the Zephyr headers do.
Signed-off-by: Leandro Pereira <leandro.pereira@intel.com>
Add SPI fixup defines on STM32 SoC family level for all SPIs that
are supported on one or more SOCs of that SoC family.
Signed-off-by: Daniel Wagenknecht <wagenknecht.daniel@gmail.com>
The xtensa headers use this for simplicity when SMP is not enabled.
It should still build on older platforms that don't include the
asm2-style CPU pointer scheme.
Signed-off-by: Andy Ross <andrew.j.ross@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>
It's not impossible that something we just handled (e.g. a machine
exception) called k_thread_abort() on our current thread. Don't try
to return into it, check the DEAD state.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
In asm2, the machine exception handler runs in interrupt context (this
is good: it allows us to defer the test against exception type until
after we have done the stack switch and dispatched any true
interrupts), but that means that the user error handler needs to be
invoked and then return through the interrupt exit code.
So the __attribute__(__noreturn__) that it was being decorated with
was incorrect. And actually fatal, as with gcc xtensa will crash
trying to return from a noreturn call.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
When in SMP mode, the nested/irq_stack/current fields are specific to
the current CPU and not to the kernel as a whole, so we need an array
of these. Place them in a _cpu_t struct and implement a
_arch_curr_cpu() function to retrieve the pointer.
When not in SMP mode, the first CPU's fields are defined as a unioned
with the first _cpu_t record. This permits compatibility with legacy
assembly on other platforms. Long term, all users, including
uniprocessor architectures, should be updated to use the new scheme.
Fundamentally this is just renaming: the structure layout and runtime
code do not change on any existing platforms and won't until someone
defines a second CPU.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The xtensa-asm2 work included a patch that added nano_internal.h
includes in lots of places that needed to have _Swap defined, because
it had to break a cycle and this no longer got pulled in from the arch
headers.
Unfortunately those new includes created new and more amusing cycles
elsewhere which led to breakage on other platforms.
Break out the _Swap definition (only) into a separate header and use
that instead. Cleaner. Seems not to have any more hidden gotchas.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Simply define the Kconfig variables in this patch so they can be used
in later patches. Define MP_NUM_CPUS correctly on esp32. No code
changes.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
This is a mostly-internal API to start a secondary system CPU, with an
implementation for the ESP-32 "APP" cpu. Exposed in kernel.h because
it's plausibly useful for asymmetric MP code managed by an app.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Xtensa register windows have a special exception that happens when the
stack pointer needs to be moved, but the caller function has already
spilled its registers below it.
I thought these were unexercised in Zephyr code, but they turn out to
be thrown by the existing mem_pool tests when run in the 32-register
qemu environment (but not on 64-register hardwre). Because the effect
of the exception is to unspill the caller, there is no good way to
handle this in a traditional handler. Instead put a 5-instruction
stub in front of the user exception handler (i.e. incurring that cost
on every trap and every L1 interrupt) to test before doing the normal
entry.
Works, but would be nicer to optimize this in the future so that only
true alloca exceptions take that cost.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
This macro was already available add an external symbol so C code can
access it (via CALL0 -- it's not and can't be an actual function).
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The API allows any byte count for stack size, and tests in fact check
that a stack with a 499 byte stack works correctly. No choice, have
to do this at runtime.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
You'd this feature would be portable, but it's arch-specific.
Initialize the CONFIG_THREAD_MONITOR stuff, placing the __thread_entry
struct (which AFAICT is dead: nothing in the tree actually reads it)
at the top of the stack.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The stack initilaization was calling the user-provided entry function
directly, which works fine until that function returns, at which point
it will try to unspill A0-A3 from the 16 bytes above the allocated
stack and then "return" to a NULL pointer.
The kernel provides a _thread_entry() function that does cleanup
properly, so use that.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
When using _arch_switch() context switching, the thread return value
is a generic hook and not provided by the architecture.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
This adds vectors for all interrupt levels defined by core-isa.h.
Modify the entry code a little bit to select correct linker sections
(levels 1, 6 and 7 get special names for... no particularly good
reason) and to constructed the interrupted PS value correctly (no EPS1
register for exceptions since they had to have interrupted level 0
code and thus differ only in the EXCM bit).
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
This python script reads the core-isa.h interrupt definitions (via
running a template file through the toolchain preprocessor to generate
an input file) and emits a fully populated, optimized C handling code
that binary searches only the declared interrupts at a given level and
correctly detects spurious interrupts (and/or incorrect core-isa.h
definitions).
The generated code, alas, turns out not to be any faster than simply
searching the interrupt mask with CLZ (er, NSAU in xtensese), though
it could be faster in theory if the compiler made different choices,
see comments. But I like this for the robustness of the fully
populated search trees and the checking of level vs. mask.
This simply commits the script output into the source tree, including
some checking code to force a build error if the toolchain changes the
headers incompatibly. It would be better long term to have these
headers be generated at build time, but that requires more cmake fu
than I have.
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>
Legacy xtensa had a rather complicated implementation of en/disabling
interrupts, owing to the "software priority" feature (which plays
games with INTENABLE and INTLEVEL to allow for interrupts to interrupt
each other outside their normal priorities). But that's not a Zephyr
feature, it's enabled by a XT_USE_SWPRI value that comes from platform
headers and isn't enabled on any of our boards. Dead code, basically.
Replace with the obvious implementation when asm2 is in use.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
This was a dead API. Nothing ever used it, it wasn't exposed in any
API headers. It never appeared in documentation. It's not
particularly clear why a Zephy app would want to hook
architecture-specific exceptions instead of simply using the portable
error framework anyway. And it's not supported by asm2. Delete.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The existing __swap() mechanism is too high level for some
applications because of its scheduler-awareness. This introduces a
new _arch_switch() mechanism, which is a simpler primitive that looks
like:
void _arch_switch(void *handle, void **old_handle_out);
The new thread handle (typically just a stack pointer) is specified
explicitly instead of being picked up from the scheduler by
per-architecture code, and on return the "old" thread handle that got
switched out is returned through the pointer.
The new primitive (currently available only on xtensa) is selected
when CONFIG_USE_SWITCH is "y". A new C _Swap() implementation based
on this primitive is then added which operates compatibly.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
_Swap() is defined in nano_internal.h. Everything calls _Swap().
Pretty much nothing that called _Swap() included nano_internal.h,
expecting it to be picked up automatically through other headers (as
it happened, from the kernel arch-specific include file). A new
_Swap() is going to need some other symbols in the inline definition,
so I needed to break that cycle. Now nothing sees _Swap() defined
anymore. Put nano_internal.h everywhere it's needed.
Our kernel includes remain a big awful yucky mess. This makes things
more correct but no less ugly. Needs cleanup.
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>
Xtensa has a "high priority" class of interrupt levels which ignore
the EXCM bit and can thus interrupt running exception handlers. These
can't be used for C handlers in the general case[1] because C code
needs to be able to throw window over/underflow exceptions, which are
not reentrant.
But the high priority interrupts might be useful to a carefully
designed application, or to unit tests of low level architecture code.
So make their generation optional with this kconfig option.
[1] ESP-32 has a high priority interrupt for its watchdog, apparently.
Which is sort of OK given that it never needs to return to the
interrupted code.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The new thread stack layout is as follow:
|---------------------|
| user stack |
|---------------------|
| stack guard (opt.) |
|---------------------|
| privilege stack |
-----------------------
For MPUv2
* user stack is aligned to the power of 2 of user stack size
* the stack guard is 2048 bytes
* the default size of privileg stack is 256 bytes.
For user thread, the following MPU regions are needded
* one region for user stack, no need of stack guard for user stack
* one region for stack guard when stack guard is enbaled
* regions for memory domain.
For kernel thread, the stack guard region will be at the top, adn
The user stack and privilege stack will be merged.
MPUv3 is the same as V2's layout, except no need of power of 2
alignment.
* reimplement the user mode enter function. Now it's possible for
kernel thread to drop privileg to user thread.
* add a separate entry for user thread
* bug fixes in the cleanup of regs when go to user mode
Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
when USERSPACE is enabled, exception is handled in the privilege
stack of thread. This make thread context switch is possible in the
exception handler. For some case,e.g. tests, this is useful.
Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
disable the U bit of irq.ctrl, so the user thread's context will
be saved into privilege stack when interrupts/exception come.
Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
scrub all the regs of kernel context before returnning to userspace.
For sys call, ro is not cleared as it's a return value of sys call.
Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
Enable us bit to check user mode more efficienly.
US is read as zero in user mode. This will allow use mode sleep
instructions, and it enables a form of denial-of-service attack
by putting the processor in sleep mode, but since interrupt
level/mask can't be set from user space that's not worse than
executing a loop without yielding.
Signed-off-by: Wayne Ren <wei.ren@synopsys.com>
Michael Hope