[Silabs] : Fix EM4 conditions (Auto-merged by platform-bot) (#73896) (#73916)

* move IRQ just before em4 entry , similar to bootlaoder

* use SL_IDLE_MODE_DURATION_S as OT child supervision timeout

* fix define and apply comments

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------


(cherry picked from commit 8a7dd55)

Co-authored-by: sarthak shaha <sarthak.shaha@silabs.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: 3 people

examples/platform/silabs/MatterConfig.cpp

@@ -407,12 +407,14 @@ void OnEM4Trigger(uint32_t duration)
     BURTC_CounterReset();
     BURTC_CompareSet(0, duration);
 
-    BURTC_IntEnable(BURTC_IEN_COMP); // compare match
-    NVIC_EnableIRQ(BURTC_IRQn);
     BURTC_Enable(true);
     EMU_EM4Init_TypeDef em4Init = EMU_EM4INIT_DEFAULT;
     EMU_EM4Init(&em4Init);
     BURTC_CounterReset();
+
+    BURTC_IntClear(BURTC_IF_COMP);
+    BURTC_IntEnable(BURTC_IEN_COMP); // compare match
+    NVIC_EnableIRQ(BURTC_IRQn);
     EMU_EnterEM4();
 }
 

examples/platform/silabs/efr32/project_include/OpenThreadConfig.h

@@ -39,11 +39,9 @@
 #ifdef SL_ICD_ENABLED
 #define OPENTHREAD_CONFIG_PARENT_SEARCH_ENABLE 0
 
-// In seconds
-#define SL_MLE_TIMEOUT_s (SL_TRANSPORT_IDLE_INTERVAL / 1000)
-
-// Timeout after 2 missed checkin or 4 mins if sleep interval is too short.
-#define OPENTHREAD_CONFIG_MLE_CHILD_TIMEOUT_DEFAULT ((SL_MLE_TIMEOUT_s < 120) ? 240 : ((SL_MLE_TIMEOUT_s * 2) + 1))
+// Timeout after 2 missed check-ins, or 4 mins if sleep interval is too short.
+#define OPENTHREAD_CONFIG_MLE_CHILD_TIMEOUT_DEFAULT                                                                                \
+    (((SL_TRANSPORT_IDLE_INTERVAL / 1000) < 120) ? 240 : (((SL_TRANSPORT_IDLE_INTERVAL / 1000) * 2) + 1))
 
 #if defined(SL_CSL_ENABLE) && SL_CSL_ENABLE || SL_CONFIG_OPENTHREAD_LIB
 
@@ -57,6 +55,12 @@
 
 #endif // SL_CSL_ENABLE || SL_CONFIG_OPENTHREAD_LIB
 
+// Keep child-supervision check aligned with LIT idle so it cannot wake the device
+// mid-idle before the EM4 / slow-poll window.
+#ifndef OPENTHREAD_CONFIG_CHILD_SUPERVISION_CHECK_TIMEOUT
+#define OPENTHREAD_CONFIG_CHILD_SUPERVISION_CHECK_TIMEOUT SL_IDLE_MODE_DURATION_S
+#endif
+
 #endif // SL_ICD_ENABLED
 
 /****Uncomment below section for OpenThread Debug logs*/