esp32/mpconfigport: Enable Zcmp opcodes for ESP32P4.

This commit enables support for Zcmp opcodes when the firmware is built
to target ESP32P4 microcontrollers.

The ESP32P4 explicitly supports the Zcmp extension for reducing the
amount of code needed for function prologues and epilogues (see section
4.1.1.1 of the ESP32P4 datasheet).

Signed-off-by: Alessandro Gatti <a.gatti@frob.it>

Author: agatti

ports/esp32/esp32_common.cmake

@@ -244,7 +244,11 @@ set(MICROPY_TARGET ${COMPONENT_TARGET})
 if(CONFIG_IDF_TARGET_ARCH_XTENSA)
     set(MICROPY_CROSS_FLAGS -march=xtensawin)
 elseif(CONFIG_IDF_TARGET_ARCH_RISCV)
-    set(MICROPY_CROSS_FLAGS -march=rv32imc)
+    if (CONFIG_IDF_TARGET_ESP32P4)
+        set(MICROPY_CROSS_FLAGS "-march=rv32imc -march-flags=zcmp")
+    else()
+        set(MICROPY_CROSS_FLAGS -march=rv32imc)
+    endif()
 endif()
 
 # Set compile options for this port.

ports/esp32/mpconfigport.h

@@ -44,6 +44,9 @@
 #define MICROPY_EMIT_RV32                   (0)
 #else
 #define MICROPY_EMIT_RV32                   (1)
+#if CONFIG_IDF_TARGET_ESP32P4
+#define MICROPY_EMIT_RV32_ZCMP              (1)
+#endif
 #endif
 #else
 #define MICROPY_EMIT_XTENSAWIN              (1)