From bbf919709f5451c801863bba8ccf596d316e5207 Mon Sep 17 00:00:00 2001
From: Erhan Kurubas <erhan.kurubas@espressif.com>
Date: Sun, 16 May 2021 18:51:28 +0300
Subject: [PATCH] gcov: added dbg stub capabilites and magic number entry to
 keep backward compatible

---
 components/app_trace/gcov/gcov_rtio.c         |  6 +++--
 components/esp_system/dbg_stubs.c             | 12 +++++++++
 .../include/esp_private/dbg_stubs.h           | 27 +++++++++++++++----
 3 files changed, 38 insertions(+), 7 deletions(-)

diff --git a/components/app_trace/gcov/gcov_rtio.c b/components/app_trace/gcov/gcov_rtio.c
index 524e1cb3ff..8bd21852b4 100644
--- a/components/app_trace/gcov/gcov_rtio.c
+++ b/components/app_trace/gcov/gcov_rtio.c
@@ -106,7 +106,7 @@ static int esp_dbg_stub_gcov_dump_do(void)
 }
 
 /**
- * @brief Triggers gcov info dump.
+ * @brief Triggers gcov info dump task
  *        This function is to be called by OpenOCD, not by normal user code.
  * TODO: what about interrupted flash access (when cache disabled)???
  *
@@ -114,11 +114,13 @@ static int esp_dbg_stub_gcov_dump_do(void)
  */
 static int esp_dbg_stub_gcov_entry(void)
 {
-    return esp_dbg_stub_gcov_dump_do();
+    s_do_dump = true;
+    return ESP_OK;
 }
 
 int gcov_rtio_atexit(void (*function)(void) __attribute__ ((unused)))
 {
+    uint32_t capabilities = 0;
     ESP_EARLY_LOGV(TAG, "%s", __FUNCTION__);
     esp_dbg_stub_entry_set(ESP_DBG_STUB_ENTRY_GCOV, (uint32_t)&esp_dbg_stub_gcov_entry);
     return 0;
diff --git a/components/esp_system/dbg_stubs.c b/components/esp_system/dbg_stubs.c
index ef49c5524d..3505930895 100644
--- a/components/esp_system/dbg_stubs.c
+++ b/components/esp_system/dbg_stubs.c
@@ -75,6 +75,7 @@ void esp_dbg_stubs_init(void)
     s_dbg_stubs_ctl_data.data_alloc     = (uint32_t)esp_dbg_stubs_data_alloc;
     s_dbg_stubs_ctl_data.data_free      = (uint32_t)esp_dbg_stubs_data_free;
 
+    s_stub_entry[ESP_DBG_STUB_MAGIC_NUM] = ESP_DBG_STUB_MAGIC_NUM_VAL;
     s_stub_entry[ESP_DBG_STUB_CONTROL_DATA] = (uint32_t)&s_dbg_stubs_ctl_data;
     eri_write(ESP_DBG_STUBS_TRAX_REG, (uint32_t)s_stub_entry);
     ESP_LOGV(TAG, "%s stubs %x", __func__, eri_read(ESP_DBG_STUBS_TRAX_REG));
@@ -91,4 +92,15 @@ esp_err_t esp_dbg_stub_entry_set(esp_dbg_stub_id_t id, uint32_t entry)
     return ESP_OK;
 }
 
+esp_err_t esp_dbg_stub_entry_get(esp_dbg_stub_id_t id, uint32_t *entry)
+{
+    if (id < ESP_DBG_STUB_ENTRY_FIRST || id >= ESP_DBG_STUB_ENTRY_MAX) {
+        ESP_LOGE(TAG, "Invalid stub id %d!", id);
+        return ESP_ERR_INVALID_ARG;
+    }
+    *entry = s_stub_entry[id];
+
+    return ESP_OK;
+}
+
 #endif
diff --git a/components/esp_system/include/esp_private/dbg_stubs.h b/components/esp_system/include/esp_private/dbg_stubs.h
index f3f5fba3b7..2b3b4f56f2 100644
--- a/components/esp_system/include/esp_private/dbg_stubs.h
+++ b/components/esp_system/include/esp_private/dbg_stubs.h
@@ -24,13 +24,18 @@ extern "C" {
  * Debug stubs entries IDs
  */
 typedef enum {
-    ESP_DBG_STUB_CONTROL_DATA,	///< stubs descriptor entry
+    ESP_DBG_STUB_MAGIC_NUM,
+    ESP_DBG_STUB_CONTROL_DATA,   ///< stubs descriptor entry
     ESP_DBG_STUB_ENTRY_FIRST,
-    ESP_DBG_STUB_ENTRY_GCOV		///< GCOV entry
-    						= ESP_DBG_STUB_ENTRY_FIRST,
+    ESP_DBG_STUB_ENTRY_GCOV	///< GCOV entry
+        = ESP_DBG_STUB_ENTRY_FIRST,
+    ESP_DBG_STUB_CAPABILITIES,
     ESP_DBG_STUB_ENTRY_MAX
 } esp_dbg_stub_id_t;
 
+#define ESP_DBG_STUB_MAGIC_NUM_VAL      0xFEEDBEEF
+#define ESP_DBG_STUB_CAP_GCOV_TASK      (1 << 0)
+
 /**
  * @brief  Initializes debug stubs.
  *
@@ -45,12 +50,24 @@ void esp_dbg_stubs_init(void);
  *
  * @param id 	Stub ID.
  * @param entry Stub entry. Usually it is stub entry function address,
- *              but can be any value meaningfull for OpenOCD command/code.
- *
+ *              but can be any value meaningfull for OpenOCD command/code
+ *              such as capabilities
  * @return ESP_OK on success, otherwise see esp_err_t
  */
 esp_err_t esp_dbg_stub_entry_set(esp_dbg_stub_id_t id, uint32_t entry);
 
+/**
+ * @brief   Retrives the corresponding stub entry
+ *
+ * @param id 	Stub ID.
+ * @param entry Stub entry. Usually it is stub entry function address,
+ *              but can be any value meaningfull for OpenOCD command/code
+ *              such as capabilities
+ *
+ * @return ESP_OK on success, otherwise see esp_err_t
+ */
+esp_err_t esp_dbg_stub_entry_get(esp_dbg_stub_id_t id, uint32_t *entry);
+
 #ifdef __cplusplus
 }
 #endif