1 files changed, 67 insertions, 0 deletions
diff --git a/ports/stm32/rng.c b/ports/stm32/rng.c
new file mode 100644
index 000000000..c0c5e9aeb
--- /dev/null
+++ b/ports/stm32/rng.c
@@ -0,0 +1,67 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2013, 2014 Damien P. George
+ *
+ * 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 <string.h>
+
+#include "py/obj.h"
+#include "rng.h"
+
+#if MICROPY_HW_ENABLE_RNG
+
+/// \moduleref pyb
+
+STATIC RNG_HandleTypeDef RNGHandle = {.Instance = NULL};
+
+void rng_init0(void) {
+    // reset the RNG handle
+    memset(&RNGHandle, 0, sizeof(RNG_HandleTypeDef));
+    RNGHandle.Instance = RNG;
+}
+
+void rng_init(void) {
+    __RNG_CLK_ENABLE();
+    HAL_RNG_Init(&RNGHandle);
+}
+
+uint32_t rng_get(void) {
+    if (RNGHandle.State == HAL_RNG_STATE_RESET) {
+        rng_init();
+    }
+    return HAL_RNG_GetRandomNumber(&RNGHandle);
+}
+
+/// \function rng()
+/// Return a 30-bit hardware generated random number.
+STATIC mp_obj_t pyb_rng_get(void) {
+    if (RNGHandle.State == HAL_RNG_STATE_RESET) {
+        rng_init();
+    }
+    return mp_obj_new_int(HAL_RNG_GetRandomNumber(&RNGHandle) >> 2);
+}
+
+MP_DEFINE_CONST_FUN_OBJ_0(pyb_rng_get_obj, pyb_rng_get);
+
+#endif // MICROPY_HW_ENABLE_RNG