zephyr/Makefile: Add minimal port.

zephyr/Makefile

@@ -54,7 +54,7 @@ SRC_QSTR += $(SRC_C)
 OBJ = $(PY_O) $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
 
 CFLAGS = $(KBUILD_CFLAGS) $(NOSTDINC_FLAGS) $(ZEPHYRINCLUDE) \
-	 -std=gnu99 -DNDEBUG -DMICROPY_HEAP_SIZE=$(MICROPY_HEAP_SIZE) $(INC)
+	 -std=gnu99 -DNDEBUG -DMICROPY_HEAP_SIZE=$(MICROPY_HEAP_SIZE) $(CFLAGS_EXTRA) $(INC)
 
 include ../py/mkrules.mk
 
@@ -83,6 +83,9 @@ $(Z_SYSGEN_H):
 	rm -f $(LIBMICROPYTHON)
 	-$(MAKE) -f Makefile.zephyr BOARD=$(BOARD) CONF_FILE=$(CONF_FILE)
 
+minimal:
+	$(MAKE) BOARD=$(BOARD) CFLAGS_EXTRA='-DMP_CONFIGFILE="<mpconfigport_minimal.h>"' FROZEN_DIR=
+
 # Clean Zephyr things too
 clean: z_clean
 

zephyr/README.md

@@ -74,3 +74,22 @@ starts from 0). You will need to adjust it for another board (using board's
 reference materials). To execute the above sample, copy it to clipboard, in
 MicroPython REPL enter "paste mode" using Ctrl+E, paste clipboard, press
 Ctrl+D to finish paste mode and start execution.
+
+
+Minimal build
+-------------
+
+MicroPython is committed to maintain minimal binary size for Zephyr port
+below 128KB, as long as Zephyr project is committed to maintain stable
+minimal size of their kernel (which they appear to be). Note that at such
+size, there is no support for any Zephyr features beyond REPL over UART,
+and only very minimal set of builtin Python modules. Thus, this build
+is more suitable for code size control and quick demonstrations even on
+smaller systems. It's also suitable for careful enabling of features one
+by one to achieve needed functionality and code size. This is in contrast
+to the "default" build, which may get more and more features enabled by
+default over time.
+
+To make a minimal build:
+
+    make BOARD=<board> minimal

zephyr/main.c

@@ -72,7 +72,9 @@ int real_main(void) {
     #endif
     mp_init();
     MP_STATE_PORT(mp_kbd_exception) = mp_obj_new_exception(&mp_type_KeyboardInterrupt);
+    #if MICROPY_MODULE_FROZEN
     pyexec_frozen_module("main.py");
+    #endif
     #if MICROPY_REPL_EVENT_DRIVEN
     pyexec_event_repl_init();
     for (;;) {

zephyr/mpconfigport_minimal.h

+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016 Linaro Limited
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include <alloca.h>
+
+// Include Zephyr's autoconf.h, which should be made first by Zephyr makefiles
+#include "autoconf.h"
+
+// Usually passed from Makefile
+#ifndef MICROPY_HEAP_SIZE
+#define MICROPY_HEAP_SIZE (16 * 1024)
+#endif
+
+#define MICROPY_STACK_CHECK         (1)
+#define MICROPY_ENABLE_GC           (1)
+#define MICROPY_HELPER_REPL         (1)
+#define MICROPY_REPL_AUTO_INDENT    (1)
+#define MICROPY_CPYTHON_COMPAT      (0)
+#define MICROPY_PY_ASYNC_AWAIT      (0)
+#define MICROPY_PY_ATTRTUPLE        (0)
+#define MICROPY_PY_BUILTINS_ENUMERATE (0)
+#define MICROPY_PY_BUILTINS_FILTER  (0)
+#define MICROPY_PY_BUILTINS_MIN_MAX (0)
+#define MICROPY_PY_BUILTINS_PROPERTY (0)
+#define MICROPY_PY_BUILTINS_RANGE_ATTRS (0)
+#define MICROPY_PY_BUILTINS_REVERSED (0)
+#define MICROPY_PY_BUILTINS_SET     (0)
+#define MICROPY_PY_BUILTINS_SLICE   (0)
+#define MICROPY_PY_ARRAY            (0)
+#define MICROPY_PY_COLLECTIONS      (0)
+#define MICROPY_PY_CMATH            (0)
+#define MICROPY_PY_IO               (0)
+#define MICROPY_PY_STRUCT           (0)
+#define MICROPY_PY_SYS_MODULES      (0)
+#define MICROPY_LONGINT_IMPL (MICROPY_LONGINT_IMPL_LONGLONG)
+#define MICROPY_FLOAT_IMPL (MICROPY_FLOAT_IMPL_FLOAT)
+#define MICROPY_PY_BUILTINS_COMPLEX (0)
+
+// Saving extra crumbs to make sure binary fits in 128K
+#define MICROPY_COMP_CONST_FOLDING  (0)
+#define MICROPY_COMP_CONST (0)
+#define MICROPY_COMP_DOUBLE_TUPLE_ASSIGN (0)
+
+#ifdef CONFIG_BOARD
+#define MICROPY_HW_BOARD_NAME "zephyr-" CONFIG_BOARD
+#else
+#define MICROPY_HW_BOARD_NAME "zephyr-generic"
+#endif
+
+#ifdef CONFIG_SOC
+#define MICROPY_HW_MCU_NAME CONFIG_SOC
+#else
+#define MICROPY_HW_MCU_NAME "unknown-cpu"
+#endif
+
+typedef int mp_int_t; // must be pointer size
+typedef unsigned mp_uint_t; // must be pointer size
+
+typedef void *machine_ptr_t; // must be of pointer size
+typedef const void *machine_const_ptr_t; // must be of pointer size
+typedef long mp_off_t;
+
+#define BYTES_PER_WORD (sizeof(mp_int_t))
+
+#define MP_STATE_PORT MP_STATE_VM
+
+#define MICROPY_PORT_ROOT_POINTERS \
+    mp_obj_t mp_kbd_exception; \
+    const char *readline_hist[8];