The user thread cannot be trusted so do not use the stack pointer it
passes in. Use the thread's privilege stack when in privileged modes to
make sure a user thread does not trick the svc/isr handlers into writing
to memory it should not.
Signed-off-by: Bradley Bolen <bbolen@lexmark.com>
Change fixes a build warning related to attribute ignored in
declaration of struct. The __packed attribute is removed.
Signed-off-by: Marek Pieta <Marek.Pieta@nordicsemi.no>
This adds code to swap_helper.S which does special handling of LR when
the interrupt came from secure. The LR value is stored to memory, and
put back into LR when swapping back to the relevant thread.
Also, add special handling of FP state when switching from secure to
non-secure, since we don't know whether the original non-secure thread
(which called a secure service) was using FP registers, so we always
store them, just in case.
Signed-off-by: Øyvind Rønningstad <oyvind.ronningstad@nordicsemi.no>
Introduce an additional single-bit flag to hold
the current length of the MPU Stack Guard size
(long or default) for the case when building
with MPU_STACK_GUARD and FPU_SHARING, in Cortex-M
platforms.
In addition, the commit adds some documentation
about the existing status flags in Arm's
thread arch.mode variable.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
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>
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>
Before introducing the code for ARM64 (AArch64) we need to relocate the
current ARM code to a new AArch32 sub-directory. For now we can assume
that no code is shared between ARM and ARM64.
There are no functional changes. The code is moved to the new location
and the file paths are fixed to reflect this change.
Signed-off-by: Carlo Caione <ccaione@baylibre.com>
