review update, add RP2040 example

Author: Bob Abeles

locale/circuitpython.pot

@@ -2140,6 +2140,10 @@ msgstr ""
 msgid "Unable to access unaliged IO register"
 msgstr ""
 
+#: ports/raspberrypi/common-hal/memorymap/AddressRange.c
+msgid "Unable to access unaligned IO register"
+msgstr ""
+
 #: ports/atmel-samd/common-hal/audiobusio/I2SOut.c
 #: ports/atmel-samd/common-hal/audioio/AudioOut.c
 #: ports/raspberrypi/common-hal/audiobusio/I2SOut.c
@@ -4048,6 +4052,10 @@ msgstr ""
 msgid "source_bitmap must have value_count of 8"
 msgstr ""
 
+#: shared-bindings/memorymap/AddressRange.c
+msgid "start must be an int"
+msgstr ""
+
 #: py/objstr.c
 msgid "start/end indices"
 msgstr ""

ports/raspberrypi/common-hal/memorymap/AddressRange.c

@@ -90,7 +90,7 @@ void common_hal_memorymap_addressrange_set_bytes(const memorymap_addressrange_ob
         case IO:
             if ((size_t)dest_addr & 0x03 || len & 0x03) {
                 // Unaligned access or unaligned length not supported by RP2 for IO registers
-                mp_raise_RuntimeError(translate("Unable to access unaliged IO register"));
+                mp_raise_RuntimeError(translate("Unable to access unaligned IO register"));
             } else {
                 // Aligned access and length, use 32-bit writes
                 uint32_t *dest_addr32 = (uint32_t *)dest_addr;

py/argcheck.c

@@ -115,8 +115,6 @@ void mp_arg_parse_all(size_t n_pos, const mp_obj_t *pos, mp_map_t *kws, size_t n
             out_vals[i].u_bool = mp_obj_is_true(given_arg);
         } else if ((allowed[i].flags & MP_ARG_KIND_MASK) == MP_ARG_INT) {
             out_vals[i].u_int = mp_obj_get_int(given_arg);
-        } else if ((allowed[i].flags & MP_ARG_KIND_MASK) == MP_ARG_UINT) {
-            out_vals[i].u_uint = mp_obj_get_uint(given_arg);
         } else {
             assert((allowed[i].flags & MP_ARG_KIND_MASK) == MP_ARG_OBJ);
             out_vals[i].u_obj = given_arg;

py/obj.c

@@ -420,21 +420,6 @@ bool mp_obj_get_int_maybe(mp_const_obj_t arg, mp_int_t *value) {
     return true;
 }
 
-mp_uint_t mp_obj_get_uint(mp_const_obj_t arg) {
-    if (arg == mp_const_false) {
-        return 0;
-    } else if (arg == mp_const_true) {
-        return 1;
-    } else if (mp_obj_is_small_int(arg)) {
-        return MP_OBJ_SMALL_INT_VALUE(arg);
-    } else if (mp_obj_is_type(arg, &mp_type_int)) {
-        return mp_obj_int_get_uint_checked(arg);
-    } else {
-        mp_obj_t res = mp_unary_op(MP_UNARY_OP_INT, (mp_obj_t)arg);
-        return mp_obj_int_get_uint_checked(res);
-    }
-}
-
 #if MICROPY_PY_BUILTINS_FLOAT
 bool mp_obj_get_float_maybe(mp_obj_t arg, mp_float_t *value) {
     mp_float_t val;

py/obj.h

@@ -939,7 +939,6 @@ static MP_INLINE bool mp_obj_is_integer(mp_const_obj_t o) {
 mp_int_t mp_obj_get_int(mp_const_obj_t arg);
 mp_int_t mp_obj_get_int_truncated(mp_const_obj_t arg);
 bool mp_obj_get_int_maybe(mp_const_obj_t arg, mp_int_t *value);
-mp_uint_t mp_obj_get_uint(mp_const_obj_t arg);
 #if MICROPY_PY_BUILTINS_FLOAT
 mp_float_t mp_obj_get_float(mp_obj_t self_in);
 bool mp_obj_get_float_maybe(mp_obj_t arg, mp_float_t *value);

py/objint.c

@@ -438,10 +438,6 @@ mp_int_t mp_obj_int_get_checked(mp_const_obj_t self_in) {
     return MP_OBJ_SMALL_INT_VALUE(self_in);
 }
 
-mp_uint_t mp_obj_int_get_uint_checked(mp_const_obj_t self_in) {
-    return MP_OBJ_SMALL_INT_VALUE(self_in);
-}
-
 
 #endif // MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_NONE
 

py/runtime.h

@@ -45,7 +45,6 @@ typedef enum {
     MP_ARG_BOOL      = 0x001,
     MP_ARG_INT       = 0x002,
     MP_ARG_OBJ       = 0x003,
-    MP_ARG_UINT      = 0x004,
     MP_ARG_KIND_MASK = 0x0ff,
     MP_ARG_REQUIRED  = 0x100,
     MP_ARG_KW_ONLY   = 0x200,

shared-bindings/memorymap/AddressRange.c

@@ -47,23 +47,58 @@
 //|        import memorymap
 //|        rtc_slow_mem = memorymap.AddressRange(start=0x50000000, length=0x2000)
 //|        rtc_slow_mem[0:3] = b"\xcc\x10\x00"
+//|
+//|     Example I/O register usage on RP2040::
+//|
+//|        import binascii
+//|        import board
+//|        import digitalio
+//|        import memorymap
+//|
+//|        def rp2040_set_pad_drive(p, d):
+//|            pads_bank0 = memorymap.AddressRange(start=0x4001C000, length=0x4000)
+//|            pad_ctrl = int.from_bytes(pads_bank0[p*4+4:p*4+8], "little")
+//|            # Pad control register is updated using an MP-safe atomic XOR
+//|            pad_ctrl ^= (d << 4)
+//|            pad_ctrl &= 0x00000030
+//|            pads_bank0[p*4+0x3004:p*4+0x3008] = pad_ctrl.to_bytes(4, "little")
+//|
+//|        def rp2040_get_pad_drive(p):
+//|            pads_bank0 = memorymap.AddressRange(start=0x4001C000, length=0x4000)
+//|            pad_ctrl = int.from_bytes(pads_bank0[p*4+4:p*4+8], "little")
+//|            return (pad_ctrl >> 4) & 0x3
+//|
+//|        # set GPIO16 pad drive strength to 12 mA
+//|        rp2040_set_pad_drive(16, 3)
+//|
+//|        # print GPIO16 pad drive strength
+//|        print(rp2040_get_pad_drive(16))
 //|     """
 
 //|     def __init__(self, *, start, length) -> None:
 //|         """Constructs an address range starting at ``start`` and ending at
-//|         ``start + length - 1``. An exception will be raised if any of the
+//|         ``start + length``. An exception will be raised if any of the
 //|         addresses are invalid or protected."""
 //|         ...
 STATIC mp_obj_t memorymap_addressrange_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
     enum { ARG_start, ARG_length };
     static const mp_arg_t allowed_args[] = {
-        { MP_QSTR_start, MP_ARG_KW_ONLY | MP_ARG_REQUIRED | MP_ARG_UINT },
+        { MP_QSTR_start, MP_ARG_KW_ONLY | MP_ARG_REQUIRED | MP_ARG_OBJ },
         { MP_QSTR_length, MP_ARG_KW_ONLY | MP_ARG_REQUIRED | MP_ARG_INT },
     };
     mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
     mp_arg_parse_all_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
 
-    size_t start = args[ARG_start].u_uint;
+    // Argument start is a pointer into the address map, so we validate it here because a
+    // signed int argument will overflow if it is in the upper half of the map.
+    size_t start;
+    if (mp_obj_is_small_int(args[ARG_start].u_obj)) {
+        start = MP_OBJ_SMALL_INT_VALUE(args[ARG_start].u_obj);
+    } else if (mp_obj_is_type(args[ARG_start].u_obj, &mp_type_int)) {
+        start = mp_obj_int_get_uint_checked(args[ARG_start].u_obj);
+    } else {
+        mp_raise_TypeError(translate("start must be an int"));
+    }
     size_t length =
         mp_arg_validate_int_min(args[ARG_length].u_int, 1, MP_QSTR_length);
     // Check for address range wrap here as this can break port-specific code due to size_t overflow.