ZBOSS NCP build optimization

[DaKa]

Hello,

I build the ZBOSS NCP sample from NCS v2.6.0 for the nRF52840 dongle.
I use the optimization flag -O2 (for speed) in the build configuration (VS Code NCS extension), and this causes the NCP to crash and reset when I send the ZDO_MGMT_NWK_UPDATE_REQ request.

Could you try this out and confirm that there is an issue with the firmware after optimization?

Best regards,
Damien

[Marte Myrvold]

Hi Damien,

I have been able to reproduce the issue. I am looking into it and will get back to you.

Best regards,
Marte

[Marte Myrvold]

Hi Damien,

I have reported this to the developers. I will let you know when I have an update.

Best regards,
Marte

[DaKa]

Hello,

Anything new on this?

BR,
Damien

[Marte Myrvold]

Hi Damien,

The developers have started looking into it, but I do not have any updates yet.

Best regards,
Marte

[Marte Myrvold]

Hi Damien,

The problem can be fixed by adding NOP instructions to time-critical code in sdk-nrfxlib/nrf_802154/driver/, like this:

diff --git a/nrf_802154/driver/src/nrf_802154_request_swi.c b/nrf_802154/driver/src/nrf_802154_request_swi.c
index fe1b43a6..6bb8ab08 100644
--- a/nrf_802154/driver/src/nrf_802154_request_swi.c
+++ b/nrf_802154/driver/src/nrf_802154_request_swi.c
@@ -292,6 +292,10 @@ static inline void assert_interrupt_status(void)
     {                                              \
         assert_interrupt_status();                 \
         func_swi(__VA_ARGS__, &result);            \
+        __NOP();                                   \
+        __NOP();                                   \
+        __NOP();                                   \
+        __NOP();                                   \
     }                                              \
                                                    \
     return result;
@@ -307,6 +311,10 @@ static inline void assert_interrupt_status(void)
     {                                                 \
         assert_interrupt_status();                    \
         func_swi(&result);                            \
+        __NOP();                                      \
+        __NOP();                                      \
+        __NOP();                                      \
+        __NOP();                                      \
     }                                                 \
                                                       \
     return result;

Let me know if this also fixes the issue on your side.

Please note that the -O2 option is non-default, so we cannot guarantee that all nRF Connect SDK components are tested with it.

Best regards,
Marte