In the Cortex-M exception table we rename z_arm_reserved()
function to z_arm_exc_spurious(), as it is invoked when
existing (that is, non-reserved) but un-installed exceptions
are triggered, accidentaly, by software, or hardware. This
currently applies to SysTick and SecureFault exceptions.
Since fault.S is shared between Cortex-M and other AARCH32
architectures, we keep z_arm_reserved as a defined symbol
there. This commit does some additional, minor, "no-op"
cleanup in #ifdef's for Cortex-M and Cortex-R.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
If the Cortex-M core does not implement the Security Extension,
we should not be adding z_arm_reserved in the corresponding
vector table entry. That is because the entry is reserved by
the ARM architecture.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
If the Cortex-M core does not implement the SysTick peripheral,
we should not be adding z_arm_reserved in the corresponding
vector table entry. If we do have SysTick implemented but we
are not using it as the system timer, we shall install the
reserved interrupt at the vector table entry.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
Write 0x0 instead of z_arm_reserved to vector exception
entries that are always reserved for future use by the
ARM architecture. These vector table entries cannot be
fetched to be executed by the Cortex-M exception entry,
so having z_arm_reserved gives a false impression, since
it is a function that may be invoked in the code. This
modification is safe since these vector entries are also
not supposed to be read / written by the code.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
The current context preservation implementation saves the spsr and
lr_irq registers, which contain the cpsr and pc register values of the
interrupted context, in the thread callee-saved block and this prevents
nesting of interrupts because these values are required to be part of
the exception stack frame to preserve the nested interrupt context.
This commit reworks the AArch32 non-Cortex-M context preservation
implementation to save the spsr and lr_irq registers in the exception
stack frame to allow preservation of the nested interrupt context as
well as the interrupted thread context.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
In the current implementation both SPSR and ELR registers are saved with
the callee-saved registers and restored by the context-switch routine.
To support nested IRQs we have to save those on the stack when entering
and exiting from an ISR.
Since the values are now carried on the stack we can now add those to
the ESF and the initial stack and take care to restore them for new
threads using the new thread wrapper routine.
Signed-off-by: Carlo Caione <ccaione@baylibre.com>
Out-of-tree code can still be using the old file locations. Introduce
header shims to include the headers from the new correct location and
print a warning message.
These shims should be removed after two releases.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This commit renames the `cortex_r` directory under the AArch32 to
`cortex_a_r`, in preparation for the AArch32 Cortex-A support.
The rationale for this renaming is that the Cortex-A and Cortex-R share
the same base design and the difference between them, other than the
MPU vs. MMU, is minimal.
Since most of the architecture port code and configurations will be
shared between the Cortex-A and Cortex-R architectures, it is
advantageous to have them together in the same directory.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This commit re-organises AArch32 configurations for consistency.
1. Move Cortex-M-specific includes to `cortex_m/Kconfig`.
2. Relocate the "TrustZone" configurations to `cortex_m/tz/Kconfig`
since these are really the TrustZone-M configurations and do not
apply to the TrustZone-A.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
Rewrite the comments for the swap routine removing the references to the
old aarch32 code and rename z_arm64_pendsv() ->
z_arm64_context_switch().
Signed-off-by: Carlo Caione <ccaione@baylibre.com>
Rework the assembly code for the ISR wrapper and SVC to share the
entry/exit code that is currently scattered amoung several files /
places. No functional changes.
Rename also macro.h -> macro.inc to fool the CI.
Signed-off-by: Carlo Caione <ccaione@baylibre.com>
z_CpuIdleInit has been renamed to z_arm_cpu_idle_init, so
we need to correct that function's name in the documentation
of arch_cpu_atomic_idle.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
This commit adds the required memory barriers to the `arch_cpu_idle`
function in order to ensure proper idle operation in all cases.
1. Add ISB after setting BASEPRI to ensure that the new wake-up
interrupt priority is visible to the WFI instruction.
2. Add DSB before WFI to ensure that all memory transactions are
completed before going to sleep.
3. Add ISB after CPSIE to ensure that the pending wake-up interrupt
is serviced immediately.
Co-authored-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
The current AArch32 `arch_cpu_idle` implementation enables interrupt
before executing the WFI instruction, and this has the side effect of
allowing interruption and thereby calling wake-up notification
functions before the CPU enters sleep.
This commit fixes the problem described above by ensuring that
interrupt is disabled when the WFI instruction is executed and
re-enabled only after the processor wakes up.
For ARMv6-M, ARMv8-M Baseline and ARM-R, the PRIMASK (ARM-M)/
CPSR.I (ARM-R) is used to lock interrupts and therefore it is not
necessary to do anything before executing the WFI instruction.
For ARMv7-M and ARMv8-M Mainline, the BASEPRI is used to lock
interrupts and the PRIMASK is always cleared in non-interrupt context;
therefore, it is necessary to set the PRIMASK to mask interrupts,
before clearing the BASEPRI to configure wake-up interrupt priority to
the lowest.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This never needed to be put in a separate gperf table.
Privilege mode stacks can be generated by the main
gen_kobject_list.py logic, which we do here.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
The nRF53 has different region size than nRF91.
This patch is aware of Erratum 19 (wrong SPU region size).
Signed-off-by: Øyvind Rønningstad <oyvind.ronningstad@nordicsemi.no>
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>
z_arm_exc_exit (z_arm_int_exit) requires the current execution mode to
be specified as a parameter (through r0). This is not necessary because
this value can be directly read from CPSR.
This commit modifies the exception return function to retrieve the
current execution mode from CPSR and removes all provisions for passing
the execution mode parameter.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
The current AArch64 interrupt system relies on the multi-level
interrupt mechanism and the `irq_nextlevel` public interface to invoke
the Generic Interrupt Controller (GIC) driver functions.
Since the GIC driver has been refactored to provide a direct interface,
in order to resolve various implementation issues described in the GIC
driver refactoring commit, the architecture interrupt control functions
are updated to directly invoke the GIC driver functions.
This commit also adds support for the ARMv8 cores (e.g. Cortex-A53)
that allow interfacing to a custom external interrupt controller
(i.e. non-GIC) by mapping the architecture interrupt control functions
to the SoC layer interrupt control functions when
`ARM_CUSTOM_INTERRUPT_CONTROLLER` configuration is enabled.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
The current AArch32 (Cortex-R and to-be-added Cortex-A) interrupt
system relies on the multi-level interrupt mechanism and the
`irq_nextlevel` public interface to invoke the Generic Interrupt
Controller (GIC) driver functions.
Since the GIC driver has been refactored to provide a direct interface,
in order to resolve various implementation issues described in the GIC
driver refactoring commit, the architecture interrupt control functions
are updated to directly invoke the GIC driver functions.
This commit also adds support for the Cortex-R cores (Cortex-R4 and R5)
that allow interfacing to a custom external interrupt controller
(i.e. non-GIC) by introducing the `ARM_CUSTOM_INTERRUPT_CONTROLLER`
configuration that maps the architecture interrupt control functions to
the SoC layer interrupt control functions.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
We rename the z_arm_int_lib_init() function to
z_arm_interrupt_init(), aligning to how other
ARCHes name their IRQ initialization function.
There is nothing about 'library' in this
functionality, so we remove the 'lib' in-fix.
The commit does not introduce any behavior changes.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
We align the implementation of z_irq_spurious() handler
with the other Zephyr ARCHEs, i.e. we will be calling
directly the ARM-specific fatal error function with
K_ERR_SPURIOUS_IRQ as the error type. This is already
the case for aarch64.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
Correct documentation note in z_irq_spurious() definition,
stressing that the function is installed in _sw_isr_table
entries at boot time (which may be or not be used for
dynamic interrupts).
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
The ARMv7-R architecture supports both Thumb-2 (T32) and ARM (A32)
instruction sets.
This commit selects the `ISA_THUMB2` symbol to indicate that the
ARMv7-R architecture supports the Thumb-2 instruction set, which can
be enabled by selecting the `COMPILER_ISA_THUMB2` symbol.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This commit introduces the `COMPILER_ISA_THUMB2` symbol to allow
choosing either the ARM or Thumb instruction set for C code
compilation.
In addition, this commit introduces the `ASSEMBLER_ISA_THUMB2` helper
symbol to specify the default target instruction set for the assembler.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This function is widely used by functions that validate memory
buffers. Macros used to check permissions, like Z_SYSCALL_MEMORY_READ
and Z_SYSCALL_MEMORY_WRITE, use these functions to check that a
pointers passed by user threads in a syscall.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
We need an unsigned comparison when evaluating whether
the supplied syscall ID is lower than the syscall ID limit.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
The ARMv7-M MPU requires power-of-two alignment, not the ARMv8-M MPU, as
noted a few lines later.
Signed-off-by: Anders Montonen <Anders.Montonen@iki.fi>
Upon reset, the CONTROL.FPCA bit is, normally, cleared. However,
it might be left un-cleared by firmware running before Zephyr boot,
for example when Zephyr image is loaded by another image.
We must clear this bit to prevent errors in exception unstacking.
This caused stack offset when booting from a build-in EFM32GG bootloader
Fixes#22977
Signed-off-by: Luuk Bosma <l.bosma@interay.com>
Upon reset, the Co-Processor Access Control Register is, normally,
0x00000000. However, it might be left un-cleared by firmware running
before Zephyr boot.
This restores the register back to reset value, even if CONFIG_FLOAT
is not set.
Clearing before setting supports switching between Full access
and Privileged access only.
Refactor enable_floating_point to support initialize
floating point registers for every CPU that has a FPU.
Signed-off-by: Luuk Bosma <l.bosma@interay.com>
Add zephyr execution regions(text, rodata, data, noinit, bss, etc.)
with proper attributes to translation tables.
Linker script has been modified a little to align these sections to
minimum translation granule(4 kB).
With this in place, code cannot be overwritten accidently as it is
marked read only. Similarly, execution is prohibited from data/RW
section as it is marked execute-never.
Signed-off-by: Abhishek Shah <abhishek.shah@broadcom.com>
Add MMU support for ARMv8A. We support 4kB translation granule.
Regions to be mapped with specific attributes are required to be
at least 4kB aligned and can be provided through platform file(soc.c).
Signed-off-by: Abhishek Shah <abhishek.shah@broadcom.com>
We lock IRQs around writing to RNR and immediate reading of RBAR
RASR in ARMv7-M MPU driver. We do this for the functions invoked
directly or undirectly by arch_buffer_validate(). This locking
guarantees that
- arch_buffer_validate() calls by ISRs may safely preempt each
other
- arch_buffer_validate() calls by threads may safely preempt
each other (i.e via context switch -out and -in again).
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
When entering user mode, and before the privileged are dropped,
the thread switches back to using its default (user) stack. For
stack limit checking not to lead to a stack overflow, the PSPLIM
and PSP register updates need to be done with PendSV IRQ locked.
This is because context-switch (done in PendSV IRQ) reprograms
the stack pointer limit register based on the current PSP
of the thread. This commit enforces PendSV locking and
unlocking while reprogramming PSP and PSPLIM when switching to
user stack at z_arm_userspace_enter().
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
Modifying the PSP via an MSR instruction is not subject to
stack limit checking so we can remove the relevant code
block in the begining of z_arm_userspace_enter(), which clears
PSPLIM. We add a comment when setting the PSP to the privilege
stack to stress that clearing the PSPLIM is not required and it
is always a safe operation.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
When returning from a system call, the thread switches back
to using its default (user) stack. For stack limit checking
not to lead to a stack overflow, the updates of PSPLIM and
PSP registers need to be done with PendSV IRQ locked. This
is because context-switch (done in PendSV IRQ) reprograms
the stack pointer limit register based on the current PSP
of the thread. This commit enforces PendSV locking and
unlocking while reprogramming PSP and PSPLIM when returning
from a system call.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
In this commit we remove the PSPLIM clearing when entering
z_arm_do_syscall(), since we want PSPLIM to keep guarding
the user thread stack, until the thread has switched to its
privileged stack, for executing the system call.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
Thread will be in privileged mode after returning from SCVall. It
will use the default (user) stack before switching to the privileged
stack to execute the system call. We need to protect the user stack
against stack overflows until this stack transition. We update the
note in z_arm_do_syscall(), stating clearly that it executing with
stack protection when building with stack limit checking support
(ARMv8-M only).
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
When configuring the built-in stack guard, via setting the
PSPLIM register, during thread context-switch, we shall only
set PSPLIM to "guard" the thread's privileged stack area when
the thread is actually using it (PSP is on this stack).
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
We do not need to have the PSPLIM clearing directly inside
the PendSV handler and outside the function that configures
it, configure_builtin_stack_guard(), since the latter is also
invoked inside the PendSV handler. This commit moves the
PSPLIM clearing inside configure_builtin_stack_guard(). The
patch is not introducing any behavioral change on the
stack limit checking mechanism for Cortex-M.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
We add the mechanism to generate offset #defines for
thread stack info start, to be used directly in ASM.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
We introduce a macro to define the IRQ priority level for
PendsV, and use it in arch/arm/include/aarch32/exc.h
to set the PendSV IRQ level. The commit does not change
the behavior of PendSV interrupt.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
This commit adds some documentation for the exception
priority scheme for 32-bit ARM architecture variants.
In addition we document that SVCall priority level for
ARMv6-M is implicitly set to highest (by leaving it as
default).
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
Same deal as in commit eddd98f811 ("kconfig: Replace some single-symbol
'if's with 'depends on'"), for the remaining cases outside defconfig
files. See that commit for an explanation.
Will do the defconfigs separately in case there are any complaints
there.
Signed-off-by: Ulf Magnusson <Ulf.Magnusson@nordicsemi.no>
This commit fixes incorrect Cortex-R interrupt lock, unlock and state
check function implementations.
The issues can be summarised as follows:
1. The current implementation of 'z_arch_irq_lock' returns the value
of CPSR as the IRQ key and, since CPSR contains many other state
bits, this caused 'z_arch_irq_unlocked' to return false even when
IRQ is unlocked. This problem is fixed by isolating only the I-bit
of CPSR and returning this value as the IRQ key, such that it
returns a non-zero value when interrupt is disabled.
2. The current implementation of 'z_arch_irq_unlock' directly updates
the value of CPSR control field with the IRQ key and this can cause
other state bits in CPSR to be corrupted. This problem is fixed by
conditionally enabling interrupt using CPSIE instruction when the
value of IRQ key is a zero.
3. The current implementation of 'z_arch_is_in_isr' checks the value
of CPSR MODE field and returns true if its value is IRQ or FIQ.
While this does not normally cause an issue, the function can return
false when IRQ offloading is used because the offload function
executes in SVC mode. This problem is fixed by adding check for SVC
mode.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
