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targets/TARGET_NUVOTON/TARGET_NUC472/trng_api.c@153:fa9ff456f731, 2016-12-20 (annotated)

Committer:
<>
Date:
Tue Dec 20 17:27:56 2016 +0000
Revision:
153:fa9ff456f731
Parent:
149:156823d33999
Child:
163:74e0ce7f98e8
This updates the lib to the mbed lib v132

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 149:156823d33999 1 /*
<> 149:156823d33999 2 * Hardware entropy collector for NUC472's RNGA
<> 149:156823d33999 3 *
<> 149:156823d33999 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
<> 149:156823d33999 5 * SPDX-License-Identifier: Apache-2.0
<> 149:156823d33999 6 *
<> 149:156823d33999 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
<> 149:156823d33999 8 * not use this file except in compliance with the License.
<> 149:156823d33999 9 * You may obtain a copy of the License at
<> 149:156823d33999 10 *
<> 149:156823d33999 11 * http://www.apache.org/licenses/LICENSE-2.0
<> 149:156823d33999 12 *
<> 149:156823d33999 13 * Unless required by applicable law or agreed to in writing, software
<> 149:156823d33999 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
<> 149:156823d33999 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
<> 149:156823d33999 16 * See the License for the specific language governing permissions and
<> 149:156823d33999 17 * limitations under the License.
<> 149:156823d33999 18 *
<> 149:156823d33999 19 */
<> 149:156823d33999 20
<> 149:156823d33999 21 #if DEVICE_TRNG
<> 149:156823d33999 22
<> 149:156823d33999 23 #include <stdlib.h>
<> 149:156823d33999 24 #include <string.h>
<> 149:156823d33999 25 #include "cmsis.h"
<> 149:156823d33999 26 #include "NUC472_442.h"
<> 149:156823d33999 27 #include "us_ticker_api.h"
<> 149:156823d33999 28 #include "trng_api.h"
<> 149:156823d33999 29
<> 149:156823d33999 30 /*
<> 149:156823d33999 31 * Get Random number generator.
<> 149:156823d33999 32 */
<> 149:156823d33999 33 static volatile int g_PRNG_done;
<> 149:156823d33999 34
<> 149:156823d33999 35 void CRYPTO_IRQHandler()
<> 149:156823d33999 36 {
<> 149:156823d33999 37 if (PRNG_GET_INT_FLAG()) {
<> 149:156823d33999 38 g_PRNG_done = 1;
<> 149:156823d33999 39 PRNG_CLR_INT_FLAG();
<> 149:156823d33999 40 }
<> 149:156823d33999 41 }
<> 149:156823d33999 42
<> 149:156823d33999 43 static void trng_get(unsigned char *pConversionData)
<> 149:156823d33999 44 {
<> 149:156823d33999 45 uint32_t *p32ConversionData;
<> 149:156823d33999 46
<> 149:156823d33999 47 p32ConversionData = (uint32_t *)pConversionData;
<> 149:156823d33999 48
<> 149:156823d33999 49 PRNG_Open(PRNG_KEY_SIZE_256, 1, us_ticker_read());
<> 149:156823d33999 50 PRNG_Start();
<> 149:156823d33999 51 while (!g_PRNG_done);
<> 149:156823d33999 52
<> 149:156823d33999 53 PRNG_Read(p32ConversionData);
<> 149:156823d33999 54 }
<> 149:156823d33999 55
<> 149:156823d33999 56 void trng_init(trng_t *obj)
<> 149:156823d33999 57 {
<> 149:156823d33999 58 (void)obj;
<> 149:156823d33999 59 /* Unlock protected registers */
<> 149:156823d33999 60 SYS_UnlockReg();
<> 149:156823d33999 61 /* Enable IP clock */
<> 149:156823d33999 62 CLK_EnableModuleClock(CRPT_MODULE);
<> 149:156823d33999 63
<> 149:156823d33999 64 /* Lock protected registers */
<> 149:156823d33999 65 SYS_LockReg();
<> 149:156823d33999 66
<> 149:156823d33999 67 NVIC_EnableIRQ(CRPT_IRQn);
<> 149:156823d33999 68 PRNG_ENABLE_INT();
<> 149:156823d33999 69 }
<> 149:156823d33999 70
<> 149:156823d33999 71 void trng_free(trng_t *obj)
<> 149:156823d33999 72 {
<> 149:156823d33999 73 (void)obj;
<> 149:156823d33999 74 PRNG_DISABLE_INT();
<> 149:156823d33999 75 NVIC_DisableIRQ(CRPT_IRQn);
<> 149:156823d33999 76 }
<> 149:156823d33999 77
<> 149:156823d33999 78 int trng_get_bytes(trng_t *obj, uint8_t *output, size_t length, size_t *output_length)
<> 149:156823d33999 79 {
<> 149:156823d33999 80 (void)obj;
<> 149:156823d33999 81
<> 149:156823d33999 82 *output_length = 0;
<> 149:156823d33999 83 if (length < 32) {
<> 149:156823d33999 84 unsigned char tmpBuff[32];
<> 149:156823d33999 85 trng_get(tmpBuff);
<> 149:156823d33999 86 memcpy(output, &tmpBuff, length);
<> 149:156823d33999 87 *output_length = length;
<> 149:156823d33999 88 } else {
<> 153:fa9ff456f731 89 for (size_t i = 0; i < (length/32); i++) {
<> 149:156823d33999 90 trng_get(output);
<> 149:156823d33999 91 *output_length += 32;
<> 149:156823d33999 92 output += 32;
<> 149:156823d33999 93 }
<> 149:156823d33999 94 }
<> 149:156823d33999 95
<> 149:156823d33999 96 return 0;
<> 149:156823d33999 97 }
<> 149:156823d33999 98
<> 149:156823d33999 99 #endif
<> 149:156823d33999 100