MacroRat / MouseCode

Mouse code for the MacroRat

Dependencies:   ITG3200 QEI

mbed-dev/targets/TARGET_STM/trng_api.c@18:6a4db94011d3, 2017-05-14 (annotated)

Committer:
sahilmgandhi
Date:
Sun May 14 23:18:57 2017 +0000
Revision:
18:6a4db94011d3
Publishing again

Who changed what in which revision?

UserRevisionLine numberNew contents of line
sahilmgandhi 18:6a4db94011d3 1 /*
sahilmgandhi 18:6a4db94011d3 2 * Hardware entropy collector for the STM32 families
sahilmgandhi 18:6a4db94011d3 3 *
sahilmgandhi 18:6a4db94011d3 4 * Copyright (C) 2006-2016, ARM Limited, All Rights Reserved
sahilmgandhi 18:6a4db94011d3 5 * SPDX-License-Identifier: Apache-2.0
sahilmgandhi 18:6a4db94011d3 6 *
sahilmgandhi 18:6a4db94011d3 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
sahilmgandhi 18:6a4db94011d3 8 * not use this file except in compliance with the License.
sahilmgandhi 18:6a4db94011d3 9 * You may obtain a copy of the License at
sahilmgandhi 18:6a4db94011d3 10 *
sahilmgandhi 18:6a4db94011d3 11 * http://www.apache.org/licenses/LICENSE-2.0
sahilmgandhi 18:6a4db94011d3 12 *
sahilmgandhi 18:6a4db94011d3 13 * Unless required by applicable law or agreed to in writing, software
sahilmgandhi 18:6a4db94011d3 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
sahilmgandhi 18:6a4db94011d3 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
sahilmgandhi 18:6a4db94011d3 16 * See the License for the specific language governing permissions and
sahilmgandhi 18:6a4db94011d3 17 * limitations under the License.
sahilmgandhi 18:6a4db94011d3 18 *
sahilmgandhi 18:6a4db94011d3 19 */
sahilmgandhi 18:6a4db94011d3 20
sahilmgandhi 18:6a4db94011d3 21 #if defined(DEVICE_TRNG)
sahilmgandhi 18:6a4db94011d3 22
sahilmgandhi 18:6a4db94011d3 23 #include <stdlib.h>
sahilmgandhi 18:6a4db94011d3 24 #include "cmsis.h"
sahilmgandhi 18:6a4db94011d3 25 #include "trng_api.h"
sahilmgandhi 18:6a4db94011d3 26
sahilmgandhi 18:6a4db94011d3 27 /** trng_get_byte
sahilmgandhi 18:6a4db94011d3 28 * @brief Get one byte of entropy from the RNG, assuming it is up and running.
sahilmgandhi 18:6a4db94011d3 29 * @param obj TRNG obj
sahilmgandhi 18:6a4db94011d3 30 * @param pointer to the hardware generated random byte.
sahilmgandhi 18:6a4db94011d3 31 */
sahilmgandhi 18:6a4db94011d3 32 static void trng_get_byte(trng_t *obj, unsigned char *byte )
sahilmgandhi 18:6a4db94011d3 33 {
sahilmgandhi 18:6a4db94011d3 34 *byte = (unsigned char)HAL_RNG_GetRandomNumber(&obj->handle);
sahilmgandhi 18:6a4db94011d3 35 }
sahilmgandhi 18:6a4db94011d3 36
sahilmgandhi 18:6a4db94011d3 37 void trng_init(trng_t *obj)
sahilmgandhi 18:6a4db94011d3 38 {
sahilmgandhi 18:6a4db94011d3 39 #if defined(TARGET_STM32L4)
sahilmgandhi 18:6a4db94011d3 40 RCC_PeriphCLKInitTypeDef PeriphClkInitStruct;
sahilmgandhi 18:6a4db94011d3 41
sahilmgandhi 18:6a4db94011d3 42 /*Select PLLQ output as RNG clock source */
sahilmgandhi 18:6a4db94011d3 43 PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_RNG;
sahilmgandhi 18:6a4db94011d3 44 PeriphClkInitStruct.RngClockSelection = RCC_RNGCLKSOURCE_PLL;
sahilmgandhi 18:6a4db94011d3 45 HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct);
sahilmgandhi 18:6a4db94011d3 46 #endif
sahilmgandhi 18:6a4db94011d3 47
sahilmgandhi 18:6a4db94011d3 48 /* RNG Peripheral clock enable */
sahilmgandhi 18:6a4db94011d3 49 __HAL_RCC_RNG_CLK_ENABLE();
sahilmgandhi 18:6a4db94011d3 50
sahilmgandhi 18:6a4db94011d3 51 /* Initialize RNG instance */
sahilmgandhi 18:6a4db94011d3 52 obj->handle.Instance = RNG;
sahilmgandhi 18:6a4db94011d3 53 HAL_RNG_Init(&obj->handle);
sahilmgandhi 18:6a4db94011d3 54
sahilmgandhi 18:6a4db94011d3 55 /* first random number generated after setting the RNGEN bit should not be used */
sahilmgandhi 18:6a4db94011d3 56 HAL_RNG_GetRandomNumber(&obj->handle);
sahilmgandhi 18:6a4db94011d3 57
sahilmgandhi 18:6a4db94011d3 58 }
sahilmgandhi 18:6a4db94011d3 59
sahilmgandhi 18:6a4db94011d3 60 void trng_free(trng_t *obj)
sahilmgandhi 18:6a4db94011d3 61 {
sahilmgandhi 18:6a4db94011d3 62 /*Disable the RNG peripheral */
sahilmgandhi 18:6a4db94011d3 63 HAL_RNG_DeInit(&obj->handle);
sahilmgandhi 18:6a4db94011d3 64 /* RNG Peripheral clock disable - assume we're the only users of RNG */
sahilmgandhi 18:6a4db94011d3 65 __HAL_RCC_RNG_CLK_DISABLE();
sahilmgandhi 18:6a4db94011d3 66 }
sahilmgandhi 18:6a4db94011d3 67
sahilmgandhi 18:6a4db94011d3 68 int trng_get_bytes(trng_t *obj, uint8_t *output, size_t length, size_t *output_length)
sahilmgandhi 18:6a4db94011d3 69 {
sahilmgandhi 18:6a4db94011d3 70 int ret;
sahilmgandhi 18:6a4db94011d3 71
sahilmgandhi 18:6a4db94011d3 72 /* Get Random byte */
sahilmgandhi 18:6a4db94011d3 73 for( uint32_t i = 0; i < length; i++ ){
sahilmgandhi 18:6a4db94011d3 74 trng_get_byte(obj, output + i );
sahilmgandhi 18:6a4db94011d3 75 }
sahilmgandhi 18:6a4db94011d3 76
sahilmgandhi 18:6a4db94011d3 77 *output_length = length;
sahilmgandhi 18:6a4db94011d3 78 /* Just be extra sure that we didn't do it wrong */
sahilmgandhi 18:6a4db94011d3 79 if( ( __HAL_RNG_GET_FLAG(&obj->handle, (RNG_FLAG_CECS | RNG_FLAG_SECS)) ) != 0 ) {
sahilmgandhi 18:6a4db94011d3 80 ret = -1;
sahilmgandhi 18:6a4db94011d3 81 } else {
sahilmgandhi 18:6a4db94011d3 82 ret = 0;
sahilmgandhi 18:6a4db94011d3 83 }
sahilmgandhi 18:6a4db94011d3 84
sahilmgandhi 18:6a4db94011d3 85 return( ret );
sahilmgandhi 18:6a4db94011d3 86 }
sahilmgandhi 18:6a4db94011d3 87
sahilmgandhi 18:6a4db94011d3 88 #endif