a752c7ab
 elopes
add first test an...
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
|
/*
* Copyright (C) 2014-2016 Freie Universitรคt Berlin
* Copyright (C) 2014 PHYTEC Messtechnik GmbH
*
* This file is subject to the terms and conditions of the GNU Lesser
* General Public License v2.1. See the file LICENSE in the top level
* directory for more details.
*/
/**
* @ingroup cpu_kinetis_common
* @ingroup drivers_periph_hwng
*
* @{
*
* @file
* @brief HWRNG interface implementation
*
* @author Johann Fischer <j.fischer@phytec.de> (adaption for Freescale's RNGA)
* @author Hauke Petersen <hauke.petersen@fu-berlin.de>
*
* @}
*/
#include "cpu.h"
#include "periph/hwrng.h"
#include "periph_conf.h"
#ifdef KINETIS_RNGA
void hwrng_init(void)
{
/* nothing to do here */
}
void hwrng_read(void *buf, unsigned int num)
{
unsigned int count = 0;
uint8_t *b = (uint8_t *)buf;
/* power on and enable the device */
HWRNG_CLKEN();
KINETIS_RNGA->CR = RNG_CR_INTM_MASK | RNG_CR_HA_MASK | RNG_CR_GO_MASK;
/* self-seeding */
while (!(KINETIS_RNGA->SR & RNG_SR_OREG_LVL_MASK));
KINETIS_RNGA->ER = KINETIS_RNGA->OR ^ (uint32_t)buf;
while (count < num) {
/* wait for random data to be ready to read */
while (!(KINETIS_RNGA->SR & RNG_SR_OREG_LVL_MASK));
uint32_t tmp = KINETIS_RNGA->OR;
/* copy data into result vector */
for (int i = 0; i < 4 && count < num; i++) {
b[count++] = (uint8_t)tmp;
tmp = tmp >> 8;
}
}
/* power of the device */
KINETIS_RNGA->CR = 0;
HWRNG_CLKDIS();
}
#endif /* KINETIS_RNGA */
|