cortex-m3-qemu: a working port

cortex-m3-qemu/Makefile

+include ../py/mkenv.mk
+-include mpconfigport.mk
+
+# qstr definitions (must come before including py.mk)
+QSTR_DEFS = qstrdefsport.h
+
+# include py core make definitions
+include ../py/py.mk
+
+CROSS_COMPILE = arm-none-eabi-
+
+CFLAGS_CORTEX_M3 = -mthumb -mcpu=cortex-m3
+CFLAGS = -I. -I$(PY_SRC) -Wall -ansi -std=gnu99 $(CFLAGS_CORTEX_M3) $(COPT)
+
+#Debugging/Optimization
+ifeq ($(DEBUG), 1)
+CFLAGS += -g -DPENDSV_DEBUG
+COPT = -O0
+else
+COPT += -Os -DNDEBUG
+endif
+
+#LDFLAGS = --nostdlib -T stm32f405.ld -Map=$(@:.elf=.map) --cref
+LDFLAGS = -lm -T generic-m-hosted.ld # -Map=$(@:.elf=.map) --cref
+LIBS =
+
+# uncomment this if you want libgcc
+#LIBS += $(shell $(CC) -print-libgcc-file-name)
+
+SRC_C = \
+	help.c \
+	math.c \
+
+	#gccollect.c \
+	#pyexec.c \
+
+SRC_S = \
+	gchelper.s \
+
+OBJ =
+OBJ += $(PY_O)
+OBJ += $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
+OBJ += $(addprefix $(BUILD)/, $(SRC_S:.s=.o))
+
+all: $(BUILD)/flash.elf
+
+run:
+	qemu-system-arm -cpu cortex-m3 -nographic -monitor null -serial null -semihosting -kernel $(BUILD)/flash.elf
+
+$(BUILD)/flash.elf: $(OBJ)
+	$(Q)$(CC) $(CFLAGS) $(LDFLAGS) main.c -o $@ $(OBJ) $(LIBS)
+	$(Q)$(SIZE) $@
+
+include ../py/mkrules.mk

cortex-m3-qemu/gccollect.c

+#include <stdio.h>
+
+//#include <stm32f4xx_hal.h>
+
+#include "misc.h"
+#include "mpconfig.h"
+#include "qstr.h"
+#include "obj.h"
+#include "gc.h"
+#include "gccollect.h"
+
+machine_uint_t gc_helper_get_regs_and_sp(machine_uint_t *regs);
+
+// obsolete
+// void gc_helper_get_regs_and_clean_stack(machine_uint_t *regs, machine_uint_t heap_end);
+
+void gc_collect(void) {
+    // get current time, in case we want to time the GC
+    uint32_t start = HAL_GetTick();
+
+    // start the GC
+    gc_collect_start();
+
+    // scan everything in RAM before the heap
+    // this includes the data and bss segments
+    // TODO possibly don't need to scan data, since all pointers should start out NULL and be in bss
+    gc_collect_root((void**)&_ram_start, ((uint32_t)&_ebss - (uint32_t)&_ram_start) / sizeof(uint32_t));
+
+    // get the registers and the sp
+    machine_uint_t regs[10];
+    machine_uint_t sp = gc_helper_get_regs_and_sp(regs);
+
+    // trace the stack, including the registers (since they live on the stack in this function)
+    gc_collect_root((void**)sp, ((uint32_t)&_ram_end - sp) / sizeof(uint32_t));
+
+    // end the GC
+    gc_collect_end();
+
+    if (0) {
+        // print GC info
+        uint32_t ticks = HAL_GetTick() - start; // TODO implement a function that does this properly
+        gc_info_t info;
+        gc_info(&info);
+        printf("GC@%lu %lums\n", start, ticks);
+        printf(" %lu total\n", info.total);
+        printf(" %lu : %lu\n", info.used, info.free);
+        printf(" 1=%lu 2=%lu m=%lu\n", info.num_1block, info.num_2block, info.max_block);
+    }
+}
+
+static mp_obj_t pyb_gc(void) {
+    gc_collect();
+    return mp_const_none;
+}
+
+MP_DEFINE_CONST_FUN_OBJ_0(pyb_gc_obj, pyb_gc);

cortex-m3-qemu/gccollect.h

+// variables defining memory layout
+// (these probably belong somewhere else...)
+extern uint32_t _etext;
+extern uint32_t _sidata;
+extern uint32_t _ram_start;
+extern uint32_t _sdata;
+extern uint32_t _edata;
+extern uint32_t _sbss;
+extern uint32_t _ebss;
+extern uint32_t _heap_start;
+extern uint32_t _heap_end;
+extern uint32_t _estack;
+extern uint32_t _ram_end;
+
+void gc_collect(void);
+
+MP_DECLARE_CONST_FUN_OBJ(pyb_gc_obj);

cortex-m3-qemu/gchelper.s

+    .syntax unified
+    .cpu cortex-m4
+    .thumb
+    .text
+    .align  2
+
+@ uint gc_helper_get_regs_and_sp(r0=uint regs[10])
+    .global gc_helper_get_regs_and_sp
+    .thumb
+    .thumb_func
+    .type   gc_helper_get_regs_and_sp, %function
+gc_helper_get_regs_and_sp:
+    @ store registers into given array
+    str     r4, [r0], #4
+    str     r5, [r0], #4
+    str     r6, [r0], #4
+    str     r7, [r0], #4
+    str     r8, [r0], #4
+    str     r9, [r0], #4
+    str     r10, [r0], #4
+    str     r11, [r0], #4
+    str     r12, [r0], #4
+    str     r13, [r0], #4
+
+    @ return the sp
+    mov     r0, sp
+    bx      lr
+
+
+@ this next function is now obsolete
+
+    .size   gc_helper_get_regs_and_clean_stack, .-gc_helper_get_regs_and_clean_stack
+@ void gc_helper_get_regs_and_clean_stack(r0=uint regs[10], r1=heap_end)
+    .global gc_helper_get_regs_and_clean_stack
+    .thumb
+    .thumb_func
+    .type   gc_helper_get_regs_and_clean_stack, %function
+gc_helper_get_regs_and_clean_stack:
+    @ store registers into given array
+    str     r4, [r0], #4
+    str     r5, [r0], #4
+    str     r6, [r0], #4
+    str     r7, [r0], #4
+    str     r8, [r0], #4
+    str     r9, [r0], #4
+    str     r10, [r0], #4
+    str     r11, [r0], #4
+    str     r12, [r0], #4
+    str     r13, [r0], #4
+
+    @ clean the stack from given pointer up to current sp
+    movs    r0, #0
+    mov     r2, sp
+    b.n     .entry
+.loop:
+    str     r0, [r1], #4
+.entry:
+    cmp     r1, r2
+    bcc.n   .loop
+    bx      lr
+
+    .size   gc_helper_get_regs_and_clean_stack, .-gc_helper_get_regs_and_clean_stack

cortex-m3-qemu/help.c

+#include <stdio.h>
+
+#include "nlr.h"
+#include "misc.h"
+#include "mpconfig.h"
+#include "qstr.h"
+#include "obj.h"
+
+STATIC const char *help_text =
+"Welcome to Micro Python!\n"
+"\n"
+"For online help please visit http://micropython.org/help/.\n"
+"\n"
+"Specific commands for the board:\n"
+"  pyb.info()      -- print some general information\n"
+"  pyb.gc()        -- run the garbage collector\n"
+"  pyb.repl_info(val) -- enable/disable printing of info after each command\n"
+"  pyb.delay(n)    -- wait for n milliseconds\n"
+"  pyb.udelay(n)   -- wait for n microseconds\n"
+"  pyb.switch()    -- return True/False if switch pressed or not\n"
+"  pyb.switch(f)   -- call the given function when the switch is pressed\n"
+"  pyb.Led(n)      -- create Led object for LED n (n=1,2,3,4)\n"
+"                     Led methods: on(), off(), toggle(), intensity(<n>)\n"
+"  pyb.Servo(n)    -- create Servo object for servo n (n=1,2,3,4)\n"
+"                     Servo methods: calibrate(...), pulse_width([p]), angle([x, [t]]), speed([x, [t]])\n"
+"  pyb.Accel()     -- create an Accelerometer object\n"
+"                     Accelerometer methods: x(), y(), z(), tilt(), filtered_xyz()\n"
+"  pyb.rng()       -- get a 30-bit hardware random number\n"
+"  pyb.gpio_in(port, [m])  -- set IO port to input, mode m\n"
+"  pyb.gpio_out(port, [m]) -- set IO port to output, mode m\n"
+"  pyb.gpio(port)      -- get digital port value\n"
+"  pyb.gpio(port, val) -- set digital port value, True or False, 1 or 0\n"
+"  pyb.ADC(port)   -- make an analog port object\n"
+"                     ADC methods: read()\n"
+"\n"
+"Ports are numbered X1-X12, X17-X22, Y1-Y12, or by their MCU name\n"
+"Port input modes are: pyb.PULL_NONE, pyb.PULL_UP, pyb.PULL_DOWN\n"
+"Port output modes are: pyb.PUSH_PULL, pyb.OPEN_DRAIN\n"
+"\n"
+"Control commands:\n"
+"  CTRL-A       -- on a blank line, enter raw REPL mode\n"
+"  CTRL-B       -- on a blank line, enter normal REPL mode\n"
+"  CTRL-C       -- interrupt a running program\n"
+"  CTRL-D       -- on a blank line, do a soft reset of the board\n"
+"\n"
+"For further help on a specific object, type help(obj)\n"
+;
+
+STATIC void pyb_help_print_info_about_object(mp_obj_t name_o, mp_obj_t value) {
+    printf("  ");
+    mp_obj_print(name_o, PRINT_STR);
+    printf(" -- ");
+    mp_obj_print(value, PRINT_STR);
+    printf("\n");
+}
+
+STATIC mp_obj_t pyb_help(uint n_args, const mp_obj_t *args) {
+    if (n_args == 0) {
+        // print a general help message
+        printf("%s", help_text);
+
+    } else {
+        // try to print something sensible about the given object
+
+        printf("object ");
+        mp_obj_print(args[0], PRINT_STR);
+        printf(" is of type %s\n", mp_obj_get_type_str(args[0]));
+
+        mp_map_t *map = NULL;
+        if (MP_OBJ_IS_TYPE(args[0], &mp_type_module)) {
+            map = mp_obj_dict_get_map(mp_obj_module_get_globals(args[0]));
+        } else {
+            mp_obj_type_t *type;
+            if (MP_OBJ_IS_TYPE(args[0], &mp_type_type)) {
+                type = args[0];
+            } else {
+                type = mp_obj_get_type(args[0]);
+            }
+            if (type->locals_dict != MP_OBJ_NULL && MP_OBJ_IS_TYPE(type->locals_dict, &mp_type_dict)) {
+                map = mp_obj_dict_get_map(type->locals_dict);
+            }
+        }
+        if (map != NULL) {
+            for (uint i = 0; i < map->alloc; i++) {
+                if (map->table[i].key != MP_OBJ_NULL) {
+                    pyb_help_print_info_about_object(map->table[i].key, map->table[i].value);
+                }
+            }
+        }
+    }
+
+    return mp_const_none;
+}
+
+MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_builtin_help_obj, 0, 1, pyb_help);

cortex-m3-qemu/main.c

+#include <stdint.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include "nlr.h"
+#include "misc.h"
+#include "mpconfig.h"
+#include "qstr.h"
+#include "lexer.h"
+#include "lexerunix.h"
+#include "parse.h"
+#include "obj.h"
+#include "parsehelper.h"
+#include "compile.h"
+#include "runtime0.h"
+#include "runtime.h"
+#include "repl.h"
+#include "gc.h"
+
+mp_obj_t mem_info(void) {
+    printf("mem: total=%d, current=%d, peak=%d\n", m_get_total_bytes_allocated(), m_get_current_bytes_allocated(), m_get_peak_bytes_allocated());
+    return mp_const_none;
+}
+
+mp_obj_t qstr_info(void) {
+    uint n_pool, n_qstr, n_str_data_bytes, n_total_bytes;
+    qstr_pool_info(&n_pool, &n_qstr, &n_str_data_bytes, &n_total_bytes);
+    printf("qstr pool: n_pool=%u, n_qstr=%u, n_str_data_bytes=%u, n_total_bytes=%u\n", n_pool, n_qstr, n_str_data_bytes, n_total_bytes);
+    return mp_const_none;
+}
+
+static void execute_from_lexer(mp_lexer_t *lex, mp_parse_input_kind_t input_kind, bool is_repl) {
+    if (lex == NULL) {
+        return;
+    }
+
+    if (0) {
+        // just tokenise
+        while (!mp_lexer_is_kind(lex, MP_TOKEN_END)) {
+            mp_token_show(mp_lexer_cur(lex));
+            mp_lexer_to_next(lex);
+        }
+        mp_lexer_free(lex);
+        return;
+    }
+
+    mp_parse_error_kind_t parse_error_kind;
+    mp_parse_node_t pn = mp_parse(lex, input_kind, &parse_error_kind);
+
+    if (pn == MP_PARSE_NODE_NULL) {
+        // parse error
+        mp_parse_show_exception(lex, parse_error_kind);
+        mp_lexer_free(lex);
+        return;
+    }
+
+    qstr source_name = mp_lexer_source_name(lex);
+    mp_lexer_free(lex);
+
+    /*
+    printf("----------------\n");
+    mp_parse_node_print(pn, 0);
+    printf("----------------\n");
+    */
+
+    mp_obj_t module_fun = mp_compile(pn, source_name, MP_EMIT_OPT_ASM_THUMB, is_repl);
+
+    if (module_fun == mp_const_none) {
+        // compile error
+        return;
+    }
+
+    // execute it
+    nlr_buf_t nlr;
+    if (nlr_push(&nlr) == 0) {
+        mp_call_function_0(module_fun);
+        nlr_pop();
+    } else {
+        // uncaught exception
+        mp_obj_print_exception((mp_obj_t)nlr.ret_val);
+    }
+}
+
+mp_import_stat_t mp_import_stat(const char *path) {
+    struct stat st;
+    if (stat(path, &st) == 0) {
+        if (S_ISDIR(st.st_mode)) {
+            return MP_IMPORT_STAT_DIR;
+        } else if (S_ISREG(st.st_mode)) {
+            return MP_IMPORT_STAT_FILE;
+        }
+    }
+    return MP_IMPORT_STAT_NO_EXIST;
+}
+
+static void do_str(const char *str) {
+    mp_lexer_t *lex = mp_lexer_new_from_str_len(MP_QSTR__lt_stdin_gt_, str, strlen(str), false);
+    execute_from_lexer(lex, MP_PARSE_SINGLE_INPUT, false);
+}
+
+void nlr_jump_fail(void *val) {
+    printf("FATAL: uncaught exception %p\n", val);
+    //__fatal_error("");
+}
+
+mp_lexer_t *mp_lexer_new_from_file(const char *filename) {
+  return NULL;
+}
+
+int main() {
+    qstr_init();
+    mp_init();
+    
+    //mp_obj_t m_sys = mp_obj_new_module(MP_QSTR_sys);
+    //mp_obj_t py_argv = mp_obj_new_list(0, NULL);
+    //mp_store_attr(m_sys, MP_QSTR_argv, py_argv);
+    
+    mp_store_name(qstr_from_str("mem_info"), mp_make_function_n(0, mem_info));
+    mp_store_name(qstr_from_str("qstr_info"), mp_make_function_n(0, qstr_info));
+    
+    do_str("print(123)");
+}

cortex-m3-qemu/mpconfigport.h

+#include <stdint.h>
+
+// options to control how Micro Python is built
+
+#define MICROPY_EMIT_THUMB          (0)
+#define MICROPY_EMIT_INLINE_THUMB   (0)
+#define MICROPY_MEM_STATS           (0)
+#define MICROPY_DEBUG_PRINTERS      (0)
+#define MICROPY_ENABLE_GC           (0)
+#define MICROPY_ENABLE_FINALISER    (0)
+#define MICROPY_ENABLE_REPL_HELPERS (1)
+#define MICROPY_LONGINT_IMPL        (MICROPY_LONGINT_IMPL_MPZ)
+#define MICROPY_FLOAT_IMPL          (MICROPY_FLOAT_IMPL_FLOAT)
+#define MICROPY_PATH_MAX            (128)
+#define MICROPY_ENABLE_MOD_IO       (0)
+
+// extra built in names to add to the global namespace
+extern const struct _mp_obj_fun_native_t mp_builtin_help_obj;
+#define MICROPY_EXTRA_BUILTINS \
+    { MP_OBJ_NEW_QSTR(MP_QSTR_help), (mp_obj_t)&mp_builtin_help_obj },
+
+// type definitions for the specific machine
+
+#define BYTES_PER_WORD (4)
+
+#define UINT_FMT "%lu"
+#define INT_FMT "%ld"
+
+typedef int32_t machine_int_t; // must be pointer size
+typedef uint32_t machine_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
+

cortex-m3-qemu/pyexec.c

+#include <stdlib.h>
+#include <stdio.h>
+
+#include <stm32f4xx_hal.h>
+
+#include "nlr.h"
+#include "misc.h"
+#include "mpconfig.h"
+#include "qstr.h"
+#include "misc.h"
+#include "lexer.h"
+#include "parse.h"
+#include "obj.h"
+#include "parsehelper.h"
+#include "compile.h"
+#include "runtime.h"
+#include "repl.h"
+#include "gc.h"
+#include "gccollect.h"
+#include "systick.h"
+#include "pybstdio.h"
+#include "readline.h"
+#include "pyexec.h"
+#include "storage.h"
+#include "usb.h"
+#include "build/py/py-version.h"
+
+pyexec_mode_kind_t pyexec_mode_kind = PYEXEC_MODE_FRIENDLY_REPL;
+STATIC bool repl_display_debugging_info = 0;
+
+// parses, compiles and executes the code in the lexer
+// frees the lexer before returning
+bool parse_compile_execute(mp_lexer_t *lex, mp_parse_input_kind_t input_kind, bool is_repl) {
+    mp_parse_error_kind_t parse_error_kind;
+    mp_parse_node_t pn = mp_parse(lex, input_kind, &parse_error_kind);
+    qstr source_name = mp_lexer_source_name(lex);
+
+    if (pn == MP_PARSE_NODE_NULL) {
+        // parse error
+        mp_parse_show_exception(lex, parse_error_kind);
+        mp_lexer_free(lex);
+        return false;
+    }
+
+    mp_lexer_free(lex);
+
+    mp_obj_t module_fun = mp_compile(pn, source_name, MP_EMIT_OPT_NONE, is_repl);
+    mp_parse_node_free(pn);
+
+    if (module_fun == mp_const_none) {
+        return false;
+    }
+
+    nlr_buf_t nlr;
+    bool ret;
+    uint32_t start = HAL_GetTick();
+    if (nlr_push(&nlr) == 0) {
+        usb_vcp_set_interrupt_char(VCP_CHAR_CTRL_C); // allow ctrl-C to interrupt us
+        mp_call_function_0(module_fun);
+        usb_vcp_set_interrupt_char(VCP_CHAR_NONE); // disable interrupt
+        nlr_pop();
+        ret = true;
+    } else {
+        // uncaught exception
+        // FIXME it could be that an interrupt happens just before we disable it here
+        usb_vcp_set_interrupt_char(VCP_CHAR_NONE); // disable interrupt
+        mp_obj_print_exception((mp_obj_t)nlr.ret_val);
+        ret = false;
+    }
+
+    // display debugging info if wanted
+    if (is_repl && repl_display_debugging_info) {
+        uint32_t ticks = HAL_GetTick() - start; // TODO implement a function that does this properly
+        printf("took %lu ms\n", ticks);
+        gc_collect();
+        // qstr info
+        {
+            uint n_pool, n_qstr, n_str_data_bytes, n_total_bytes;
+            qstr_pool_info(&n_pool, &n_qstr, &n_str_data_bytes, &n_total_bytes);
+            printf("qstr:\n  n_pool=%u\n  n_qstr=%u\n  n_str_data_bytes=%u\n  n_total_bytes=%u\n", n_pool, n_qstr, n_str_data_bytes, n_total_bytes);
+        }
+
+        // GC info
+        {
+            gc_info_t info;
+            gc_info(&info);
+            printf("GC:\n");
+            printf("  %lu total\n", info.total);
+            printf("  %lu : %lu\n", info.used, info.free);
+            printf("  1=%lu 2=%lu m=%lu\n", info.num_1block, info.num_2block, info.max_block);
+        }
+    }
+
+    return ret;
+}
+
+int pyexec_raw_repl(void) {
+    vstr_t line;
+    vstr_init(&line, 32);
+
+raw_repl_reset:
+    stdout_tx_str("raw REPL; CTRL-B to exit\r\n");
+
+    for (;;) {
+        vstr_reset(&line);
+        stdout_tx_str(">");
+        for (;;) {
+            char c = stdin_rx_chr();
+            if (c == VCP_CHAR_CTRL_A) {
+                // reset raw REPL
+                goto raw_repl_reset;
+            } else if (c == VCP_CHAR_CTRL_B) {
+                // change to friendly REPL
+                stdout_tx_str("\r\n");
+                vstr_clear(&line);
+                pyexec_mode_kind = PYEXEC_MODE_FRIENDLY_REPL;
+                return 0;
+            } else if (c == VCP_CHAR_CTRL_C) {
+                // clear line
+                vstr_reset(&line);
+            } else if (c == VCP_CHAR_CTRL_D) {
+                // input finished
+                break;
+            } else if (c <= 127) {
+                // let through any other ASCII character
+                vstr_add_char(&line, c);
+            }
+        }
+
+        // indicate reception of command
+        stdout_tx_str("OK");
+
+        if (line.len == 0) {
+            // exit for a soft reset
+            stdout_tx_str("\r\n");
+            vstr_clear(&line);
+            return 1;
+        }
+
+        mp_lexer_t *lex = mp_lexer_new_from_str_len(MP_QSTR__lt_stdin_gt_, line.buf, line.len, 0);
+        parse_compile_execute(lex, MP_PARSE_FILE_INPUT, false);
+
+        // indicate end of output with EOF character
+        stdout_tx_str("\004");
+    }
+}
+
+int pyexec_friendly_repl(void) {
+    vstr_t line;
+    vstr_init(&line, 32);
+
+#if defined(USE_HOST_MODE) && MICROPY_HW_HAS_LCD
+    // in host mode, we enable the LCD for the repl
+    mp_obj_t lcd_o = mp_call_function_0(mp_load_name(qstr_from_str("LCD")));
+    mp_call_function_1(mp_load_attr(lcd_o, qstr_from_str("light")), mp_const_true);
+#endif
+
+friendly_repl_reset:
+    stdout_tx_str("Micro Python build " MICROPY_GIT_HASH " on " MICROPY_BUILD_DATE "; " MICROPY_HW_BOARD_NAME " with STM32F405RG\r\n");
+    stdout_tx_str("Type \"help()\" for more information.\r\n");
+
+    // to test ctrl-C
+    /*
+    {
+        uint32_t x[4] = {0x424242, 0xdeaddead, 0x242424, 0xdeadbeef};
+        for (;;) {
+            nlr_buf_t nlr;