freertos,esp_system: make dependencies on some components optional

Dependencies on gdbstub, espcoredump, app_trace will only be added
if these components are present in the build.

components/esp_system/CMakeLists.txt

@@ -40,8 +40,8 @@ else()
                                     # [refactor-todo] requirements due to init code,
                                     # should be removable once using component init functions
                                     # link-time registration is used.
-                                    esp_pm app_update nvs_flash pthread app_trace esp_gdbstub
-                                    espcoredump esp_phy efuse
+                                    esp_pm app_update nvs_flash pthread
+                                    esp_phy efuse
                         LDFRAGMENTS "linker.lf" "app.lf")
     add_subdirectory(port)
 
@@ -72,3 +72,20 @@ endif()
 # Force linking UBSAN hooks. If UBSAN is not enabled, the hooks will ultimately be removed
 # due to -ffunction-sections -Wl,--gc-sections options.
 target_link_libraries(${COMPONENT_LIB} INTERFACE "-u __ubsan_include")
+
+
+# [refactor-todo] requirements due to init code, should be removable
+# once link-time registration of component init functions is used.
+if(CONFIG_APPTRACE_ENABLE)
+    idf_component_optional_requires(PRIVATE app_trace)
+endif()
+
+if(CONFIG_ESP_COREDUMP_ENABLE)
+    idf_component_optional_requires(PRIVATE espcoredump)
+endif()
+
+# [refactor-todo] requirement from the panic handler,
+# need to introduce panic "event" concept to remove this dependency (IDF-2194)
+if(CONFIG_ESP_SYSTEM_PANIC_GDBSTUB)
+    idf_component_optional_requires(PRIVATE esp_gdbstub)
+endif()

components/esp_system/startup.c

@@ -45,7 +45,10 @@
 #include "esp_core_dump.h"
 #endif
 
+#if CONFIG_APPTRACE_ENABLE
 #include "esp_app_trace.h"
+#endif
+
 #include "esp_private/dbg_stubs.h"
 #include "esp_pm.h"
 #include "esp_private/pm_impl.h"

components/freertos/CMakeLists.txt

@@ -68,10 +68,11 @@ if(CONFIG_ESP32_IRAM_AS_8BIT_ACCESSIBLE_MEMORY)
     list(APPEND srcs "FreeRTOS-Kernel/portable/xtensa/xtensa_loadstore_handler.S")
 endif()
 
-# esp_timer is required by FreeRTOS because we use esp_tiemr_get_time() to do profiling
-# app_trace is required by FreeRTOS headers only when CONFIG_APPTRACE_SV_ENABLE=y,
-# REQUIRES can't depend on config options, so always require it.
-set(required_components app_trace esp_timer)
+# esp_timer is required by FreeRTOS when we use esp_timer_get_time() to do profiling
+# [refactor-todo]: make this an optional requirement depending on CONFIG_FREERTOS_RUN_TIME_STATS_USING_ESP_TIMER
+# Note, many other components implicitly include esp_timer.h via freertos portmacro.h and some
+# components implicitly depend on esp_timer via freertos.
+set(required_components esp_timer)
 
 idf_component_register(SRCS "${srcs}"
                     INCLUDE_DIRS ${include_dirs}
@@ -104,3 +105,12 @@ set_source_files_properties(
 # we can't establish dependency on what we don't yet know, so we force the
 # linker to not drop this symbol.
 target_link_libraries(${COMPONENT_LIB} INTERFACE "-u app_main")
+
+if(CONFIG_APPTRACE_SV_ENABLE)
+    # FreeRTOS headers have a dependency on app_trace when SystemView tracing is enabled
+    idf_component_optional_requires(PUBLIC app_trace)
+elseif(CONFIG_APPTRACE_ENABLE)
+    # [refactor-todo]: port.c has a dependency on esp_apptrace_init, for running it on APP CPU.
+    # this should be resolved when link-time registration of startup functions is added.
+    idf_component_optional_requires(PRIVATE app_trace)
+endif()

components/freertos/FreeRTOS-Kernel/portable/xtensa/port.c

@@ -61,7 +61,9 @@
 #include "esp_system.h"
 #include "esp_log.h"
 #include "esp_int_wdt.h"
+#ifdef CONFIG_APPTRACE_ENABLE
 #include "esp_app_trace.h"    /* Required for esp_apptrace_init. [refactor-todo] */
+#endif
 #include "FreeRTOS.h"        /* This pulls in portmacro.h */
 #include "task.h"            /* Required for TaskHandle_t, tskNO_AFFINITY, and vTaskStartScheduler */
 #include "port_systick.h"

tools/test_apps/system/g1_components/CMakeLists.txt

@@ -22,9 +22,6 @@ set(extra_allowed_components
 # These components are currently included into "G1" build, but shouldn't.
 # After removing the extra dependencies, remove the components from this list as well.
 set(extra_components_which_shouldnt_be_included
-    # app_trace is a public dependency of FreeRTOS because of SystemView trace headers.
-    #   To fix, convert this into a weak public dependency conditional on CONFIG_APPTRACE_SV_ENABLE.
-    app_trace
     # app_update gets added because of bootloader_support, spi_flash, espcoredump, esp_system.
     #   bootloader_support, spi_flash, espcoredump should be removed from dependencies;
     #   esp_system code that reads app version should be made conditional on app_update being included
@@ -51,8 +48,6 @@ set(extra_components_which_shouldnt_be_included
     esp_eth
     # esp_event is a dependency of esp_wifi, esp_eth. Both should be removed from G1.
     esp_event
-    # esp_gdbstub is a dependency of esp_system, can easily be made conditional on related Kconfig option.
-    esp_gdbstub
     # esp_netif is a dependency of lwip and esp_event, should disappear once lwip is removed.
     esp_netif
     # esp_phy is a dependency of esp_system and esp_wifi. For the former, it can be made a weak dependency.
@@ -69,11 +64,6 @@ set(extra_components_which_shouldnt_be_included
     # esp_wifi is a dependency of lwip.
     #   [refactor-todo]: investigate making esp_wifi a conditional dependency.
     esp_wifi
-    # Similar to esp_gdbstub, this dependency from esp_system can be made weakly dependent
-    #   on CONFIG_ESP_COREDUMP_ENABLE.
-    #   [refactor-todo]: how will the user set CONFIG_ESP_COREDUMP_ENABLE if the component
-    #   is not included into the build, hence Kconfig option is not visible in menuconfig?
-    espcoredump
     # esptool_py is a dependency of bootloader, esp_wifi, app_update, partition_table, all of which
     #   should be removed from G1-only build.
     esptool_py

tools/test_apps/system/panic/CMakeLists.txt

@@ -2,7 +2,7 @@
 # in this exact order for cmake to work correctly
 cmake_minimum_required(VERSION 3.5)
 
-set(COMPONENTS esptool_py main)
+set(COMPONENTS main espcoredump esp_gdbstub)
 include($ENV{IDF_PATH}/tools/cmake/project.cmake)
 
 project(test_panic)