atmel-samd: Enable longints for M4 builds.

Fixes #110

Author: tannewt

ports/atmel-samd/mpconfigport.h

@@ -58,8 +58,6 @@
 #define MICROPY_PY_URANDOM_EXTRA_FUNCS (0)
 #define MICROPY_PY_STRUCT           (0)
 #define MICROPY_PY_SYS              (1)
-// If you change MICROPY_LONGINT_IMPL, also change MPY_TOOL_LONGINT_IMPL in mpconfigport.mk.
-#define MICROPY_LONGINT_IMPL        (MICROPY_LONGINT_IMPL_NONE)
 #define MICROPY_FLOAT_IMPL          (MICROPY_FLOAT_IMPL_FLOAT)
 #define MICROPY_STREAMS_NON_BLOCK   (1)
 
@@ -140,12 +138,17 @@ typedef long mp_off_t;
 #define CIRCUITPY_MCU_FAMILY samd21
 #define MICROPY_PY_SYS_PLATFORM                     "Atmel SAMD21"
 #define PORT_HEAP_SIZE (16384 + 4096)
+// If you change MICROPY_LONGINT_IMPL, also change MPY_TOOL_LONGINT_IMPL in mpconfigport.mk.
+#define MICROPY_LONGINT_IMPL        (MICROPY_LONGINT_IMPL_NONE)
 #endif
 
 #ifdef SAMD51
 #define CIRCUITPY_MCU_FAMILY samd51
 #define MICROPY_PY_SYS_PLATFORM                     "MicroChip SAMD51"
 #define PORT_HEAP_SIZE (0x20000) // 128KiB
+// If you change MICROPY_LONGINT_IMPL, also change MPY_TOOL_LONGINT_IMPL in mpconfigport.mk.
+#define MICROPY_LONGINT_IMPL        (MICROPY_LONGINT_IMPL_MPZ)
+#define MP_SSIZE_MAX (0x7fffffff)
 #endif
 
 // extra built in modules to add to the list of known ones

ports/atmel-samd/mpconfigport.mk

@@ -1,7 +1,12 @@
 # Define an equivalent for MICROPY_LONGINT_IMPL, to pass to $(MPY-TOOL) in py/mkrules.mk
 # $(MPY-TOOL) needs to know what kind of longint to use (if any) to freeze long integers.
 # This should correspond to the MICROPY_LONGINT_IMPL definition in mpconfigport.h.
+ifeq ($(CHIP_FAMILY), samd21)
 MPY_TOOL_LONGINT_IMPL = -mlongint-impl=none
+endif
 
-INTERNAL_LIBM = 1
+ifeq ($(CHIP_FAMILY), samd51)
+MPY_TOOL_LONGINT_IMPL = -mlongint-impl=mpz
+endif
 
+INTERNAL_LIBM = 1