1 files changed, 169 insertions, 0 deletions
diff --git a/os/hal/ports/NRF5/LLD/RNGv1/hal_rng_lld.c b/os/hal/ports/NRF5/LLD/RNGv1/hal_rng_lld.c
new file mode 100644
index 0000000..bf9382c
--- /dev/null
+++ b/os/hal/ports/NRF5/LLD/RNGv1/hal_rng_lld.c
@@ -0,0 +1,169 @@
+/*
+    RNG for ChibiOS - Copyright (C) 2016 Stephane D'Alu
+
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+*/
+
+/**
+ * @file    RNGv1/hal_rng_lld.c
+ * @brief   NRF5 RNG subsystem low level driver source.
+ *
+ * @addtogroup RNG
+ * @{
+ */
+
+#include "hal.h"
+
+#if (HAL_USE_RNG == TRUE) || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Driver local definitions.                                                 */
+/*===========================================================================*/
+
+/**
+ * @brief   RNG default configuration.
+ */
+static const RNGConfig default_config = {
+  .digital_error_correction = 1,
+};
+
+/*===========================================================================*/
+/* Driver exported variables.                                                */
+/*===========================================================================*/
+
+/** @brief RNGD1 driver identifier.*/
+#if NRF5_RNG_USE_RNG0 || defined(__DOXYGEN__)
+RNGDriver RNGD1;
+#endif
+
+/*===========================================================================*/
+/* Driver local variables and types.                                         */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver local functions.                                                   */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver interrupt handlers.                                                */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver exported functions.                                                */
+/*===========================================================================*/
+
+/**
+ * @brief   Low level RNG driver initialization.
+ *
+ * @notapi
+ */
+void rng_lld_init(void) {
+  rngObjectInit(&RNGD1);
+  RNGD1.rng    = NRF_RNG;
+  RNGD1.irq    = RNG_IRQn;
+}
+
+/**
+ * @brief   Configures and activates the RNG peripheral.
+ *
+ * @param[in] rngp      pointer to the @p RNGDriver object
+ *
+ * @notapi
+ */
+void rng_lld_start(RNGDriver *rngp) {
+  NRF_RNG_Type *rng = rngp->rng;
+
+  /* If not specified, set default configuration */
+  if (rngp->config == NULL)
+    rngp->config = &default_config;
+
+  /* Configure digital error correction */
+  if (rngp->config->digital_error_correction) 
+    rng->CONFIG |=  RNG_CONFIG_DERCEN_Msk;
+  else
+    rng->CONFIG &= ~RNG_CONFIG_DERCEN_Msk;
+
+  /* Clear pending events */
+  rng->EVENTS_VALRDY = 0;
+#if CORTEX_MODEL >= 4
+    (void)rng->EVENTS_VALRDY;
+#endif
+    
+  /* Set interrupt mask */
+  rng->INTENSET      = RNG_INTENSET_VALRDY_Msk;
+
+  /* Start */
+  rng->TASKS_START   = 1;
+}
+
+
+/**
+ * @brief   Deactivates the RNG peripheral.
+ *
+ * @param[in] rngp      pointer to the @p RNGDriver object
+ *
+ * @notapi
+ */
+void rng_lld_stop(RNGDriver *rngp) {
+  NRF_RNG_Type *rng = rngp->rng;
+
+  /* Stop peripheric */
+  rng->TASKS_STOP = 1;
+}
+
+
+/**
+ * @brief   Write random bytes;
+ *
+ * @param[in] rngp      pointer to the @p RNGDriver object
+ * @param[in] n         size of buf in bytes
+ * @param[in] buf       @p buffer location
+ *
+ * @notapi
+ */
+msg_t rng_lld_write(RNGDriver *rngp, uint8_t *buf, size_t n,
+                    systime_t timeout) {
+  NRF_RNG_Type *rng = rngp->rng;
+  size_t i;
+
+  for (i = 0 ; i < n ; i++) {
+    /* Wait for byte ready
+     * It take about 677µs to generate a new byte, not sure if
+     * forcing a context switch will be a benefit
+     */
+    while (rng->EVENTS_VALRDY == 0) {
+      /* Sleep and wakeup on ARM event (interrupt) */
+      SCB->SCR |= SCB_SCR_SEVONPEND_Msk;
+      __SEV();
+      __WFE();
+      __WFE();
+    }
+
+    /* Read byte */
+    buf[i] = (char)rng->VALUE;
+
+    /* Mark as read */
+    rng->EVENTS_VALRDY = 0;
+#if CORTEX_MODEL >= 4
+    (void)rng->EVENTS_VALRDY;
+#endif
+    
+    /* Clear interrupt so we can wake up again */
+    nvicClearPending(rngp->irq);
+  }
+  return MSG_OK;
+}
+
+#endif /* HAL_USE_RNG */
+
+/** @} */