Genadi Zawidowski / mbed-dev

mbed library sources. Supersedes mbed-src. Edited target satm32f446 for user USART3 pins

Dependents:   IGLOO_board

Fork of mbed-dev by mbed official

targets/TARGET_TOSHIBA/TARGET_TMPM46B/trng_api.c@184:08ed48f1de7f, 2018-04-19 (annotated)

Committer:
AnnaBridge
Date:
Thu Apr 19 17:12:19 2018 +0100
Revision:
184:08ed48f1de7f
mbed-dev library. Release version 161

Who changed what in which revision?

UserRevisionLine numberNew contents of line
AnnaBridge 184:08ed48f1de7f 1 /* mbed Microcontroller Library
AnnaBridge 184:08ed48f1de7f 2 * (C)Copyright TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION 2017 All rights reserved
AnnaBridge 184:08ed48f1de7f 3 *
AnnaBridge 184:08ed48f1de7f 4 * Licensed under the Apache License, Version 2.0 (the "License");
AnnaBridge 184:08ed48f1de7f 5 * you may not use this file except in compliance with the License.
AnnaBridge 184:08ed48f1de7f 6 * You may obtain a copy of the License at
AnnaBridge 184:08ed48f1de7f 7 *
AnnaBridge 184:08ed48f1de7f 8 * http://www.apache.org/licenses/LICENSE-2.0
AnnaBridge 184:08ed48f1de7f 9 *
AnnaBridge 184:08ed48f1de7f 10 * Unless required by applicable law or agreed to in writing, software
AnnaBridge 184:08ed48f1de7f 11 * distributed under the License is distributed on an "AS IS" BASIS,
AnnaBridge 184:08ed48f1de7f 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
AnnaBridge 184:08ed48f1de7f 13 * See the License for the specific language governing permissions and
AnnaBridge 184:08ed48f1de7f 14 * limitations under the License.
AnnaBridge 184:08ed48f1de7f 15 */
AnnaBridge 184:08ed48f1de7f 16 #include "mbed_error.h"
AnnaBridge 184:08ed48f1de7f 17 #include "tmpm46b_esg.h"
AnnaBridge 184:08ed48f1de7f 18 #include "trng_api.h"
AnnaBridge 184:08ed48f1de7f 19
AnnaBridge 184:08ed48f1de7f 20 static Result ESG_Config(void)
AnnaBridge 184:08ed48f1de7f 21 {
AnnaBridge 184:08ed48f1de7f 22 Result ret = ERROR;
AnnaBridge 184:08ed48f1de7f 23 uint16_t Fintming = 560U;
AnnaBridge 184:08ed48f1de7f 24
AnnaBridge 184:08ed48f1de7f 25 // Confirm the ESG core stops
AnnaBridge 184:08ed48f1de7f 26 if (ESG_GetCalculationStatus() == ESG_CALCULATION_COMPLETE) {
AnnaBridge 184:08ed48f1de7f 27 // Confirm no interrupt generation
AnnaBridge 184:08ed48f1de7f 28 if (ESG_GetIntStatus() == DISABLE) {
AnnaBridge 184:08ed48f1de7f 29 // Set the latch timing & output timing
AnnaBridge 184:08ed48f1de7f 30 if ((ESG_SetLatchTiming(ESG_LATCH_TIMING_1) == SUCCESS) &&
AnnaBridge 184:08ed48f1de7f 31 (ESG_SetFintiming(Fintming) == SUCCESS)) {
AnnaBridge 184:08ed48f1de7f 32 ret = SUCCESS;
AnnaBridge 184:08ed48f1de7f 33 }
AnnaBridge 184:08ed48f1de7f 34 }
AnnaBridge 184:08ed48f1de7f 35 }
AnnaBridge 184:08ed48f1de7f 36 return ret;
AnnaBridge 184:08ed48f1de7f 37 }
AnnaBridge 184:08ed48f1de7f 38
AnnaBridge 184:08ed48f1de7f 39 void trng_init(trng_t *obj)
AnnaBridge 184:08ed48f1de7f 40 {
AnnaBridge 184:08ed48f1de7f 41 // Enable clock supply
AnnaBridge 184:08ed48f1de7f 42 CG_SetFcPeriphB(CG_FC_PERIPH_ESG, ENABLE);
AnnaBridge 184:08ed48f1de7f 43 // Initialise ESG core & Start up the ESG core
AnnaBridge 184:08ed48f1de7f 44 if ((ESG_Config() == SUCCESS) && (ESG_Startup() == SUCCESS)) {
AnnaBridge 184:08ed48f1de7f 45 obj->trng_init = true;
AnnaBridge 184:08ed48f1de7f 46 } else {
AnnaBridge 184:08ed48f1de7f 47 error("TRNG is not Initialised");
AnnaBridge 184:08ed48f1de7f 48 obj->trng_init = false;
AnnaBridge 184:08ed48f1de7f 49 }
AnnaBridge 184:08ed48f1de7f 50 }
AnnaBridge 184:08ed48f1de7f 51
AnnaBridge 184:08ed48f1de7f 52 void trng_free(trng_t *obj)
AnnaBridge 184:08ed48f1de7f 53 {
AnnaBridge 184:08ed48f1de7f 54 ESG_IPReset();
AnnaBridge 184:08ed48f1de7f 55 // Disable clock supply
AnnaBridge 184:08ed48f1de7f 56 CG_SetFcPeriphB(CG_FC_PERIPH_ESG, DISABLE);
AnnaBridge 184:08ed48f1de7f 57 obj->trng_init = false;
AnnaBridge 184:08ed48f1de7f 58 }
AnnaBridge 184:08ed48f1de7f 59
AnnaBridge 184:08ed48f1de7f 60 int trng_get_bytes(trng_t *obj, uint8_t *output, size_t length, size_t *output_length)
AnnaBridge 184:08ed48f1de7f 61 {
AnnaBridge 184:08ed48f1de7f 62 volatile uint8_t random[64] = {0};
AnnaBridge 184:08ed48f1de7f 63 uint8_t i;
AnnaBridge 184:08ed48f1de7f 64 Result ret = ERROR;
AnnaBridge 184:08ed48f1de7f 65
AnnaBridge 184:08ed48f1de7f 66 *output_length = 0;
AnnaBridge 184:08ed48f1de7f 67
AnnaBridge 184:08ed48f1de7f 68 if (!obj->trng_init) {
AnnaBridge 184:08ed48f1de7f 69 error("TRNG is not Initialised");
AnnaBridge 184:08ed48f1de7f 70 return FAIL; // fail i.e. -1
AnnaBridge 184:08ed48f1de7f 71 }
AnnaBridge 184:08ed48f1de7f 72
AnnaBridge 184:08ed48f1de7f 73 while (ESG_GetIntStatus() == DISABLE) {
AnnaBridge 184:08ed48f1de7f 74 // Wait for ESG core for generating an interrupt
AnnaBridge 184:08ed48f1de7f 75 }
AnnaBridge 184:08ed48f1de7f 76 // Interrupt clearing
AnnaBridge 184:08ed48f1de7f 77 ret = ESG_ClrInt();
AnnaBridge 184:08ed48f1de7f 78 if (ret == ERROR) {
AnnaBridge 184:08ed48f1de7f 79 return FAIL; // fail i.e. -1
AnnaBridge 184:08ed48f1de7f 80 }
AnnaBridge 184:08ed48f1de7f 81 // Get the calculation result
AnnaBridge 184:08ed48f1de7f 82 ESG_GetResult((uint32_t*)random); //512-bit entropy
AnnaBridge 184:08ed48f1de7f 83
AnnaBridge 184:08ed48f1de7f 84 for (i = 0; (i < 64) && (i < length); i++) {
AnnaBridge 184:08ed48f1de7f 85 *output++ = random[i];
AnnaBridge 184:08ed48f1de7f 86 // clear the buffer
AnnaBridge 184:08ed48f1de7f 87 random[i] = 0;
AnnaBridge 184:08ed48f1de7f 88 }
AnnaBridge 184:08ed48f1de7f 89 *output_length = i;
AnnaBridge 184:08ed48f1de7f 90 //clear and restart the ESG core
AnnaBridge 184:08ed48f1de7f 91 ESG_IPReset();
AnnaBridge 184:08ed48f1de7f 92 ret |= ESG_Startup();
AnnaBridge 184:08ed48f1de7f 93 if (ret == ERROR) {
AnnaBridge 184:08ed48f1de7f 94 return FAIL; // fail i.e. -1
AnnaBridge 184:08ed48f1de7f 95 }
AnnaBridge 184:08ed48f1de7f 96
AnnaBridge 184:08ed48f1de7f 97 return ret;
AnnaBridge 184:08ed48f1de7f 98 }