change default risv-gcc to riscv-none-elf- and add _zicsr extension

add cmake for ch32v20x, skip freertos examples for CH32V20X, also skip net webserver due to lack of RAM
update to use openocd with wlinke adapter

examples/build_system/cmake/cpu/rv32i-ilp32.cmake

@@ -1,13 +1,13 @@
 if (TOOLCHAIN STREQUAL "gcc")
   set(TOOLCHAIN_COMMON_FLAGS
-    -march=rv32i
+    -march=rv32i_zicsr
     -mabi=ilp32
     )
   set(FREERTOS_PORT GCC_RISC_V CACHE INTERNAL "")
 
 elseif (TOOLCHAIN STREQUAL "clang")
   set(TOOLCHAIN_COMMON_FLAGS
-    -march=rv32i
+    -march=rv32i_zicsr
     -mabi=ilp32
     )
   set(FREERTOS_PORT GCC_RISC_V CACHE INTERNAL "")

examples/build_system/cmake/cpu/rv32imac-ilp32.cmake

@@ -1,13 +1,13 @@
 if (TOOLCHAIN STREQUAL "gcc")
   set(TOOLCHAIN_COMMON_FLAGS
-    -march=rv32imac
+    -march=rv32imac_zicsr
     -mabi=ilp32
     )
   set(FREERTOS_PORT GCC_RISC_V CACHE INTERNAL "")
 
 elseif (TOOLCHAIN STREQUAL "clang")
   set(TOOLCHAIN_COMMON_FLAGS
-    -march=rv32imac
+    -march=rv32imac_zicsr
     -mabi=ilp32
     )
   set(FREERTOS_PORT GCC_RISC_V CACHE INTERNAL "")

examples/build_system/cmake/toolchain/riscv_gcc.cmake

@@ -1,15 +1,24 @@
+# default Toolchain from https://github.com/xpack-dev-tools/riscv-none-elf-gcc-xpack
+if (NOT DEFINED CROSS_COMPILE)
+  set(CROSS_COMPILE "riscv-none-elf-")
+endif ()
+
 if (NOT DEFINED CMAKE_C_COMPILER)
-  set(CMAKE_C_COMPILER "riscv-none-embed-gcc")
+  set(CMAKE_C_COMPILER ${CROSS_COMPILE}gcc)
+endif ()
+
+if (NOT DEFINED CMAKE_C_COMPILER)
+  set(CMAKE_C_COMPILER ${CROSS_COMPILE}gcc)
 endif ()
 
 if (NOT DEFINED CMAKE_CXX_COMPILER)
-  set(CMAKE_CXX_COMPILER "riscv-none-embed-g++")
+  set(CMAKE_CXX_COMPILER ${CROSS_COMPILE}g++)
 endif ()
 
 set(CMAKE_ASM_COMPILER ${CMAKE_C_COMPILER})
-set(CMAKE_SIZE "riscv-none-embed-size" CACHE FILEPATH "")
-set(CMAKE_OBJCOPY "riscv-none-embed-objcopy" CACHE FILEPATH "")
-set(CMAKE_OBJDUMP "riscv-none-embed-objdump" CACHE FILEPATH "")
+set(CMAKE_SIZE ${CROSS_COMPILE}size CACHE FILEPATH "")
+set(CMAKE_OBJCOPY ${CROSS_COMPILE}objcopy CACHE FILEPATH "")
+set(CMAKE_OBJDUMP ${CROSS_COMPILE}objdump CACHE FILEPATH "")
 
 include(${CMAKE_CURRENT_LIST_DIR}/common.cmake)
 

examples/build_system/make/cpu/rv32i-ilp32.mk

@@ -1,12 +1,15 @@
 ifeq ($(TOOLCHAIN),gcc)
   CFLAGS += \
-    -march=rv32i \
+    -march=rv32i_zicsr \
+    -mabi=ilp32 \
+
+else ifeq ($(TOOLCHAIN),clang)
+  CFLAGS += \
+    -march=rv32i_zicsr \
     -mabi=ilp32 \
 
 else ifeq ($(TOOLCHAIN),iar)
-	#CFLAGS += --cpu cortex-a53
-	#ASFLAGS += --cpu cortex-a53
-
+  $(error not support)
 endif
 
 # For freeRTOS port source

examples/build_system/make/cpu/rv32imac-ilp32.mk

@@ -1,11 +1,15 @@
 ifeq ($(TOOLCHAIN),gcc)
   CFLAGS += \
-    -march=rv32imac \
+    -march=rv32imac_zicsr \
+    -mabi=ilp32 \
+
+else ifeq ($(TOOLCHAIN),clang)
+  CFLAGS += \
+    -march=rv32imac_zicsr \
     -mabi=ilp32 \
 
 else ifeq ($(TOOLCHAIN),iar)
-	#CFLAGS += --cpu cortex-a53
-	#ASFLAGS += --cpu cortex-a53
+  $(error not support)
 
 endif
 

examples/device/audio_4_channel_mic_freertos/skip.txt

@@ -1,3 +1,4 @@
+mcu:CH32V20X
 mcu:CH32V307
 mcu:CXD56
 mcu:F1C100S

examples/device/audio_test_freertos/skip.txt

@@ -1,3 +1,4 @@
+mcu:CH32V20X
 mcu:CH32V307
 mcu:CXD56
 mcu:F1C100S

examples/device/net_lwip_webserver/skip.txt

@@ -1,3 +1,4 @@
+mcu:CH32V20X
 mcu:LPC11UXX
 mcu:LPC13XX
 mcu:LPC15XX

examples/device/video_capture_2ch/skip.txt

@@ -2,6 +2,7 @@ mcu:MSP430x5xx
 mcu:NUC121
 mcu:SAMD11
 mcu:GD32VF103
+mcu:CH32V20X
 mcu:CH32V307
 mcu:STM32L0
 family:espressif