[Silabs] Add deep sleep support for EM4 samples apps

examples/platform/silabs/FreeRTOSConfig.h

@@ -128,6 +128,10 @@ extern uint32_t SystemCoreClock;
 #include "SEGGER_SYSVIEW_FreeRTOS.h"
 #endif
 
+#if defined(SL_MATTER_EM4_SLEEP) && (SL_MATTER_EM4_SLEEP == 1)
+void sl_matter_em4_check(uint32_t expected_idle_time_ms);
+#endif // defined(SL_MATTER_EM4_SLEEP) && (SL_MATTER_EM4_SLEEP == 1)
+
 /*-----------------------------------------------------------
  * Application specific definitions.
  *
@@ -143,6 +147,9 @@ extern uint32_t SystemCoreClock;
 /* Energy saving modes. */
 #if defined(SL_CATALOG_POWER_MANAGER_PRESENT)
 #define configUSE_TICKLESS_IDLE 1
+#if defined(SL_MATTER_EM4_SLEEP) && (SL_MATTER_EM4_SLEEP == 1)
+#define configPRE_SLEEP_PROCESSING(x) sl_matter_em4_check(x)
+#endif // defined(SL_MATTER_EM4_SLEEP) && (SL_MATTER_EM4_SLEEP == 1)
 #elif (SLI_SI91X_MCU_INTERFACE && SL_ICD_ENABLED)
 #define configUSE_TICKLESS_IDLE 1
 #define configEXPECTED_IDLE_TIME_BEFORE_SLEEP 70

examples/platform/silabs/MatterConfig.cpp

@@ -24,6 +24,17 @@
 
 #include <mbedtls/platform.h>
 
+#if CHIP_CONFIG_ENABLE_ICD_SERVER
+#if defined(SL_MATTER_EM4_SLEEP) && (SL_MATTER_EM4_SLEEP == 1)
+#include "sl_sleeptimer.h"
+#include <app/icd/server/ICDConfigurationData.h> // nogncheck
+
+#include "em_burtc.h"
+#include "em_cmu.h"
+#include "em_emu.h"
+#endif // defined(SL_MATTER_EM4_SLEEP) && (SL_MATTER_EM4_SLEEP == 1)
+#endif // CHIP_CONFIG_ENABLE_ICD_SERVER
+
 #ifdef SL_WIFI
 #include <platform/silabs/NetworkCommissioningWiFiDriver.h>
 #include <platform/silabs/wifi/WifiInterface.h> // nogncheck
@@ -339,9 +350,35 @@ CHIP_ERROR SilabsMatterConfig::InitMatter(const char * appName)
     return CHIP_NO_ERROR;
 }
 
+#if defined(SL_MATTER_EM4_SLEEP) && (SL_MATTER_EM4_SLEEP == 1)
+void OnEM4Trigger(uint32_t duration)
+{
+    CMU_ClockSelectSet(cmuClock_EM4GRPACLK, cmuSelect_ULFRCO);
+    CMU_ClockEnable(cmuClock_BURTC, true);
+    CMU_ClockEnable(cmuClock_BURAM, true);
+
+    BURTC_Init_TypeDef burtcInit = BURTC_INIT_DEFAULT;
+    burtcInit.compare0Top        = true; // reset counter when counter reaches compare value
+    burtcInit.em4comp            = true; // BURTC compare interrupt wakes from EM4 (causes reset)
+    BURTC_Init(&burtcInit);
+
+    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();
+    EMU_EnterEM4();
+}
+
+#endif // defined(SL_MATTER_EM4_SLEEP) && (SL_MATTER_EM4_SLEEP == 1)
 // ================================================================================
 // FreeRTOS Callbacks
 // ================================================================================
+
 extern "C" void vApplicationIdleHook(void)
 {
 #if (SLI_SI91X_MCU_INTERFACE && CHIP_CONFIG_ENABLE_ICD_SERVER)
@@ -351,3 +388,30 @@ extern "C" void vApplicationIdleHook(void)
     SiWxPlatformInterface::sl_si91x_uart_power_requirement_handler();
 #endif
 }
+
+#if CHIP_CONFIG_ENABLE_ICD_SERVER
+#if defined(SL_MATTER_EM4_SLEEP) && (SL_MATTER_EM4_SLEEP == 1)
+
+#ifndef SL_MATTER_EM4_THRESHOLD_PERCENTAGE
+#define SL_MATTER_EM4_THRESHOLD_PERCENTAGE 90
+#endif
+
+static_assert(SL_MATTER_EM4_THRESHOLD_PERCENTAGE > 0 && SL_MATTER_EM4_THRESHOLD_PERCENTAGE < 100,
+              "SL_MATTER_EM4_THRESHOLD_PERCENTAGE must be between 1 and 99");
+
+extern "C" void sl_matter_em4_check(uint32_t expected_idle_time_ms)
+{
+    if (chip::ICDConfigurationData::GetInstance().GetICDMode() == chip::ICDConfigurationData::ICDMode::LIT)
+    {
+        uint32_t idleDuration_seconds = chip::ICDConfigurationData::GetInstance().GetIdleModeDuration().count();
+        uint32_t threshold_ms         = idleDuration_seconds * SL_EM4_THRESHOLD_PERCENTAGE * 10;
+        // Since the sleep timer will never match the actual idle time (hardware latency, etc), we set a threshold
+        // Multiply by 10 to converts seconds into milliseconds (e.g. 90% of 1000sec in ms is 1000*90*10 = 900000ms)
+        if (expected_idle_time_ms >= threshold_ms)
+        {
+            OnEM4Trigger(expected_idle_time_ms);
+        }
+    }
+}
+#endif // defined(SL_MATTER_EM4_SLEEP) && (SL_MATTER_EM4_SLEEP == 1)
+#endif // CHIP_CONFIG_ENABLE_ICD_SERVER

third_party/silabs/efr32_sdk.gni

@@ -93,6 +93,8 @@ declare_args() {
   sl_enable_test_event_trigger = false
 
   sl_verbose_mode = false
+
+  sl_em4_sleep = false
 }
 
 examples_plat_dir = "${chip_root}/examples/platform/silabs/efr32"
@@ -506,6 +508,7 @@ template("efr32_sdk") {
       "SL_CODE_COMPONENT_OPENTHREAD=openthread",
       "SL_CODE_COMPONENT_INTERRUPT_MANAGER=interrupt_manager",
       "SL_APP_PROPERTIES",
+      "SL_MATTER_EM4_SLEEP=${sl_em4_sleep}",
     ]
 
     if (silabs_log_enabled && chip_logging) {
@@ -739,6 +742,7 @@ template("efr32_sdk") {
       "${efr32_sdk_root}/platform/emdrv/nvm3/src/nvm3_object.c",
       "${efr32_sdk_root}/platform/emdrv/nvm3/src/nvm3_page.c",
       "${efr32_sdk_root}/platform/emdrv/nvm3/src/nvm3_utils.c",
+      "${efr32_sdk_root}/platform/emlib/src/em_burtc.c",
       "${efr32_sdk_root}/platform/emlib/src/em_cmu.c",
       "${efr32_sdk_root}/platform/emlib/src/em_crypto.c",
       "${efr32_sdk_root}/platform/emlib/src/em_emu.c",