The current context save implementation saves registers of each task
to xcp context, which is unnecessary because most of the arm registers are
already saved in the task stack, this commit replace the xcp context with
stack context to improve context switching performance and reduce the tcb
space occupation of tcb instance.
Signed-off-by: chao.an <anchao@xiaomi.com>
It seems to be caused by the corrupted or wrong CPSR restored on return
from exception. NuttX restores the context using code like this:
msr spsr, r1
GCC translates this to:
msr spsr_fc, r1
As a result, not all SPSR fields are updated on exception return. This
should be:
msr spsr_fsxc, r1
This bug has been fixed by Heesub Shin in:
343243c7c0
Change-Id: Ibc64db7bceecd0fb6ef39284fb5bc467f5603e2e
All supported arch uses a push-down stack:
The stack grows toward lower addresses in memory. The stack pointer
register points to the lowest, valid working address (the "top" of
the stack). Items on the stack are referenced as positive(include zero)
word offsets from sp.
Which means that for stack in the [begin, begin + size):
1.The initial SP point to begin + size
2.push equals sub and then store
3.pop equals load and then add
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Summary:
- Apply the same logic for armv7-a
- NOTE: stack pointer alignment is 4-byte
Impact:
- Affects arm (arm7/9) and c5471 with interrupt stack enabled
Testing:
- Built with c5471evm.nsh (CONFIG_ARCH_INTERRUPTSTACK=2048)
- Built with ea3131:nsh (CONFIG_ARCH_INTERRUPTSTACK=2048)
- Not tested but should work
Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>
to save the preserved space(1KB) and also avoid the heap overhead
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: I694073f68e1bd63960cedeea1ddec441437be025
Summary
The naming standard at https://cwiki.apache.org/confluence/display/NUTTX/Naming+FAQ requires that all MCU-private functions begin with the name of the architecture, not up_.
This PR addresses only these name changes for the ARM-private functions prototyped in arm_internal.h
This change to the files only modifies the name of called functions. nxstyle fixes were made for all core architecture files. However, there are well over 5000 additional complaints from MCU drivers and board logic that are unrelated to to this change but were affected by the name change. It is not humanly possible to fix all of these. I ask that this change be treated like other cosmetic changes that we have done which do not require full nxstyle compliance.
Impact
There should be not impact of this change (other that one step toward more consistent naming).
Testing
stm32f4discovery:netnsh
Summary
The naming standard at https://cwiki.apache.org/confluence/display/NUTTX/Naming+FAQ requires that all MCU-private files begin with the name of the architecture, not up_.
This PR addresses only these name changes for the up_*.S files.
The entire job required to be compatible with that Naming Convention will also require changing the naming of the up_() functions that are used only within arch/arm and board/arm.
Impact
There should be not impact of this change (other that one step toward more consistent naming).
Testing
stm32f4discovery:netnsh
Summary
The naming standard at https://cwiki.apache.org/confluence/display/NUTTX/Naming+FAQ requires that all MCU-private files begin with the name of the architecture, not up_.
This PR addresses only these name changes for the up_*.h files. There are only three, but almost 1680 files that include them:
up_arch.h
up_internal.h
up_vfork.h
The only change to the files is from including up_arch.h to arm_arch.h (for example).
The entire job required to be compatible with that Naming Convention will also require changing the naming of the up_() functions that are used only within arch/arm and board/arm.
Impact
There should be not impact of this change (other that one step toward more consistent naming).
Testing
stm32f4discovery:netnsh
