Merge branch 'feature/lp_core_pcnt' into 'master'

feat(ulp): add pulse counter example for lp core

Closes IDF-9137

See merge request espressif/esp-idf!31163

components/ulp/lp_core/lp_core/include/ulp_lp_core_utils.h

@@ -89,6 +89,14 @@ void ulp_lp_core_sw_intr_enable(bool enable);
  */
 void ulp_lp_core_sw_intr_clear(void);
 
+/**
+ * @brief Puts the CPU into a wait state until an interrupt is triggered
+ *
+ * @note The CPU will draw less power when in this state compared to actively running
+ *
+ */
+void ulp_lp_core_wait_for_intr(void);
+
 #ifdef __cplusplus
 }
 #endif

components/ulp/lp_core/lp_core/lp_core_utils.c

@@ -145,3 +145,8 @@ void ulp_lp_core_sw_intr_clear(void)
 {
     pmu_ll_lp_clear_sw_intr_status(&PMU);
 }
+
+void ulp_lp_core_wait_for_intr(void)
+{
+    asm volatile("wfi");
+}