Commit Graph

12 Commits

Author SHA1 Message Date
Ioannis Glaropoulos
95da5d479b arch: arm: minor fixes in the docs for ARM kernel_arch headers
Fix documentation in kernel_arch_data.h and kernel_arch_func.h
headers for ARM, to indicate that these are common headers for
all ARM architecture variants.

Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
2020-04-09 13:13:42 -07:00
Stephanos Ioannidis
b63a028fbc arch: arm: aarch32: Rework non-Cortex-M context preservation
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>
2020-04-02 09:22:38 +02:00
Stephanos Ioannidis
33928f18ae arch: arm: aarch32: Add header shims for cortex_a_r renaming
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>
2020-03-26 11:20:36 +01:00
Stephanos Ioannidis
a033683783 arch: arm: aarch32: Rename cortex_r to cortex_a_r
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>
2020-03-26 11:20:36 +01:00
Andrew Boie
80a0d9d16b kernel: interrupt/idle stacks/threads as array
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>
2020-03-16 23:17:36 +02:00
Ioannis Glaropoulos
36e80673f9 arch: arm: aarch32: cortex-m: introduce offset for stack info start
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>
2020-02-19 12:19:43 -08:00
Ioannis Glaropoulos
4223b71b77 arch: aarch32: define macro for PendSV IRQ priority level
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>
2020-02-19 12:19:43 -08:00
Ioannis Glaropoulos
f9d9b7642e arch: aarch32: document exception priority scheme for 32-bit ARM
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>
2020-02-19 12:19:43 -08:00
Stephanos Ioannidis
bea3ee0ed0 arch: arm: Fix incorrect Cortex-R interrupt state control logic.
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>
2020-02-11 08:03:37 -08:00
Carlo Caione
1be0c05311 arch: arm64: Introduce ARM64 (AArch64) architecture
Introduce the basic ARM64 architecture support.

A new CONFIG_ARM64 symbol is introduced for the new architecture and new
cmake / Kconfig files are added to switch between ARM and ARM64.

Signed-off-by: Carlo Caione <ccaione@baylibre.com>
2020-02-01 08:08:43 -05:00
Carlo Caione
13e671e381 arch: arm: Fix header guards
Fix the header guards for the ARM header files to reflect the new code
location.

Signed-off-by: Carlo Caione <ccaione@baylibre.com>
2019-12-20 11:40:59 -05:00
Carlo Caione
aec9a8c4be arch: arm: Move ARM code to AArch32 sub-directory
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>
2019-12-20 11:40:59 -05:00