moved rng to LLD directory.

removed rng power control (doesn't exist in nrf52, wasn't documented in nrf51)
renamed peripheral to start at 0

4 files changed, 333 insertions, 4 deletions

diff --git a/os/hal/ports/NRF5/LLD/hal_rng_lld.c b/os/hal/ports/NRF5/LLD/hal_rng_lld.c
new file mode 100644
index 0000000..5e85981
--- /dev/null
+++ b/os/hal/ports/NRF5/LLD/hal_rng_lld.c
@@ -0,0 +1,163 @@
+/*
+    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    NRF5/LLD/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;
+
+  /* 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;
+
+    /* Clear interrupt so we can wake up again */
+    nvicClearPending(rngp->irq);
+  }
+  return MSG_OK;
+}
+
+#endif /* HAL_USE_RNG */
+
+/** @} */
diff --git a/os/hal/ports/NRF5/LLD/hal_rng_lld.h b/os/hal/ports/NRF5/LLD/hal_rng_lld.h
new file mode 100644
index 0000000..9a9f471
--- /dev/null
+++ b/os/hal/ports/NRF5/LLD/hal_rng_lld.h
@@ -0,0 +1,166 @@
+/*
+    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    NRF5/LLD/hal_rng_lld.h
+ * @brief   NRF5 RNG subsystem low level driver header.
+ *
+ * @addtogroup RNG
+ * @{
+ */
+
+#ifndef HAL_RNG_LLD_H
+#define HAL_RNG_LLD_H
+
+#if (HAL_USE_RNG == TRUE) || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Driver constants.                                                         */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Driver pre-compile time settings.                                         */
+/*===========================================================================*/
+
+/**
+ * @name    Configuration options
+ * @{
+ */
+/**
+ * @brief   RNGD1 driver enable switch.
+ * @details If set to @p TRUE the support for RNGD1 is included.
+ * @note    The default is @p FALSE.
+ */
+#if !defined(NRF5_RNG_USE_RNG0) || defined(__DOXYGEN__)
+#define NRF5_RNG_USE_RNG0                  FALSE
+#endif
+
+/**
+ * @brief   RNG interrupt priority level setting for RNG0.
+ */
+#if !defined(NRF5_RNG_RNG0_IRQ_PRIORITY) || defined(__DOXYGEN__)
+#define NRF5_RNG_RNG0_IRQ_PRIORITY         3
+#endif
+
+
+/*===========================================================================*/
+/* Derived constants and error checks.                                       */
+/*===========================================================================*/
+
+#if NRF5_RNG_USE_RNG0 == FALSE
+#error "Requesting RNG driver, but no RNG peripheric attached"
+#endif
+
+#if NRF5_RNG_USE_RNG0 &&					\
+    !OSAL_IRQ_IS_VALID_PRIORITY(NRF5_RNG_RNG0_IRQ_PRIORITY)
+#error "Invalid IRQ priority assigned to RNG0"
+#endif
+
+/*===========================================================================*/
+/* Driver data structures and types.                                         */
+/*===========================================================================*/
+
+/**
+ * @brief   Type of a structure representing an RNG driver.
+ */
+typedef struct RNGDriver RNGDriver;
+
+/**
+ * @brief   Driver configuration structure.
+ */
+typedef struct {
+  /* End of the mandatory fields.*/
+  /**
+   * @brief   Activate the digital error correction
+   *
+   * @details A digital corrector algorithm is employed to remove any
+   *          bias toward '1' or '0'. Disabling it offers a substantial
+   *          speed advantage, but may result in a statistical distribution
+   *          that is not perfectly uniform.
+   *
+   * @note    For nRF51, on average, it take 167µs to get a byte without
+   *          digitial error correction and 677µs with, but no garantee 
+   *          is made on the necessary time to generate one byte.
+   */
+  uint8_t digital_error_correction:1;
+  /**
+   * @brief   Only power the RNG device when requeting random bytes
+   *
+   * @details Device will not be powered when started/stopped 
+   *          but only when writint bytes.
+   */
+  uint8_t power_on_write:1;
+} RNGConfig;
+
+
+/**
+ * @brief   Structure representing an RNG driver.
+ */
+struct RNGDriver {
+  /**
+   * @brief Driver state.
+   */
+  rngstate_t                state;
+  /**
+   * @brief Current configuration data.
+   */
+  const RNGConfig           *config;
+#if RNG_USE_MUTUAL_EXCLUSION || defined(__DOXYGEN__)
+  /**
+   * @brief   Mutex protecting the peripheral.
+   */
+  mutex_t                   mutex;
+#endif /* RNG_USE_MUTUAL_EXCLUSION */
+  /* End of the mandatory fields.*/
+  /**
+   * @brief Pointer to the RNGx registers block.
+   */
+  NRF_RNG_Type             *rng;
+  /**
+   * @brief IRQ number
+   */
+  uint32_t                  irq;
+};
+
+/*===========================================================================*/
+/* Driver macros.                                                            */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* External declarations.                                                    */
+/*===========================================================================*/
+
+#if NRF5_RNG_USE_RNG0 && !defined(__DOXYGEN__)
+extern RNGDriver RNGD1;
+#endif /* NRF5_RNG_USE_RNG0 */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+  void rng_lld_init(void);
+  void rng_lld_start(RNGDriver *rngp);
+  void rng_lld_stop(RNGDriver *rngp);
+  msg_t rng_lld_write(RNGDriver *rngp, uint8_t *buf, size_t n,
+                      systime_t timeout);
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* HAL_USE_RNG */
+
+#endif /* HAL_RNG_LLD_H */
+
+/** @} */
diff --git a/os/hal/ports/NRF5/LLD/hal_st_lld.c b/os/hal/ports/NRF5/LLD/hal_st_lld.c
index 931f1a7..c78b4bb 100644
--- a/os/hal/ports/NRF5/LLD/hal_st_lld.c
+++ b/os/hal/ports/NRF5/LLD/hal_st_lld.c
@@ -275,8 +275,8 @@ void st_lld_init(void) {
   NRF_TIMER0->TASKS_CLEAR = 1;

 

   /*

-   * Using 32-bit mode with prescaler 16 configures this

-   * timer with a 1MHz clock.

+   * Using 32-bit mode with prescaler 1/16 configures this

+   * timer with a 1MHz clock, reducing power consumption.

    */

   NRF_TIMER0->BITMODE = TIMER_BITMODE_BITMODE_32Bit;

   NRF_TIMER0->PRESCALER = 4;

diff --git a/os/hal/ports/NRF5/LLD/hal_st_lld.h b/os/hal/ports/NRF5/LLD/hal_st_lld.h
index 3b4bf8e..9d67ce9 100644
--- a/os/hal/ports/NRF5/LLD/hal_st_lld.h
+++ b/os/hal/ports/NRF5/LLD/hal_st_lld.h
@@ -15,8 +15,8 @@
 */

 

 /**

- * @file    st_lld.h

- * @brief   NRF51822 ST subsystem low level driver header.

+ * @file    NRF5/LLD/st_lld.h

+ * @brief   NRF5 ST subsystem low level driver header.

  * @details This header is designed to be include-able without having to

  *          include other files from the HAL.

  *