feat(etm): add modem ETM support on esp32s31

Enable modem ETM capability on esp32s31 and add a dedicated modem_etm LL
implementation with the correct event/task status register mapping.

components/hal/esp32s31/include/hal/modem_etm_ll.h

@@ -0,0 +1,95 @@
+/*
+ * SPDX-FileCopyrightText: 2026 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#pragma once
+
+#include <stdlib.h>
+#include <stdbool.h>
+#include "soc/soc.h"
+#include "hal/assert.h"
+#include "soc/soc_etm_struct.h"
+#include "soc/soc_etm_reg.h"
+#include "soc/soc_etm_source.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define MODEM_LL_ETM_EVENT_TABLE(event_type) \
+    (uint32_t[4]){ \
+        [0] = MODEM_EVT_G0, \
+        [1] = MODEM_EVT_G1, \
+        [2] = MODEM_EVT_G2, \
+        [3] = MODEM_EVT_G3, \
+    }[event_type]
+
+#define MODEM_LL_ETM_TASK_TABLE(task_type) \
+    (uint32_t[4]){ \
+        [0] = MODEM_TASK_G0, \
+        [1] = MODEM_TASK_G1, \
+        [2] = MODEM_TASK_G2, \
+        [3] = MODEM_TASK_G3, \
+    }[task_type]
+
+static inline bool modem_etm_ll_get_group_event_status(int group_id)
+{
+    switch (group_id) {
+    case 0:
+        return SOC_ETM.evt_st12.modem_evt_g0_st;
+    case 1:
+        return SOC_ETM.evt_st12.modem_evt_g1_st;
+    case 2:
+        return SOC_ETM.evt_st12.modem_evt_g2_st;
+    case 3:
+        return SOC_ETM.evt_st12.modem_evt_g3_st;
+    default:
+        HAL_ASSERT(false);
+    }
+    return false;
+}
+
+static inline bool modem_etm_ll_get_group_task_status(int group_id)
+{
+    switch (group_id) {
+    case 0:
+        return SOC_ETM.task_st10.modem_task_g0_st;
+    case 1:
+        return SOC_ETM.task_st10.modem_task_g1_st;
+    case 2:
+        return SOC_ETM.task_st10.modem_task_g2_st;
+    case 3:
+        return SOC_ETM.task_st11.modem_task_g3_st;
+    default:
+        HAL_ASSERT(false);
+    }
+    return false;
+}
+
+static inline void modem_etm_ll_clear_group_event_status(int group_id)
+{
+    SOC_ETM.evt_st12_clr.val = SOC_ETM_MODEM_EVT_G0_ST_CLR << group_id;
+}
+
+static inline void modem_etm_ll_clear_group_task_status(int group_id)
+{
+    switch (group_id) {
+    case 0:
+    case 1:
+    case 2:
+        SOC_ETM.task_st10_clr.val = SOC_ETM_MODEM_TASK_G0_ST_CLR << group_id;
+        break;
+    case 3:
+        SOC_ETM.task_st11_clr.val = SOC_ETM_MODEM_TASK_G3_ST_CLR;
+        break;
+    default:
+        HAL_ASSERT(false);
+        break;
+    }
+}
+
+#ifdef __cplusplus
+}
+#endif

components/soc/esp32s31/include/soc/Kconfig.soc_caps.in

@@ -515,6 +515,10 @@ config SOC_GDMA_EXT_MEM_ENC_ALIGNMENT
     int
     default 16
 
+config SOC_MODEM_SUPPORT_ETM
+    bool
+    default y
+
 config SOC_APM_CTRL_FILTER_SUPPORTED
     bool
     default y

components/soc/esp32s31/include/soc/soc_caps.h

@@ -194,6 +194,9 @@
 // #define SOC_GDMA_SUPPORT_SLEEP_RETENTION    1 // TODO: [ESP32S31] IDF-14760
 #define SOC_GDMA_EXT_MEM_ENC_ALIGNMENT   (16)
 
+/*-------------------------- MODEM CAPS --------------------------------------*/
+#define SOC_MODEM_SUPPORT_ETM               1
+
 /*-------------------------- APM CAPS ----------------------------------------*/
 #define SOC_APM_CTRL_FILTER_SUPPORTED   1 /*!< Support for APM control filter */