You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
42 lines
955 B
42 lines
955 B
/* |
|
* Copyright (c) 2019 Antmicro <www.antmicro.com> |
|
* |
|
* SPDX-License-Identifier: Apache-2.0 |
|
*/ |
|
|
|
#define DT_DRV_COMPAT litex_prbs |
|
|
|
#include <zephyr/device.h> |
|
#include <zephyr/drivers/entropy.h> |
|
#include <errno.h> |
|
#include <zephyr/init.h> |
|
#include <soc.h> |
|
#include <string.h> |
|
#include <zephyr/kernel.h> |
|
|
|
#define PRBS_STATUS DT_INST_REG_ADDR(0) |
|
#define PRBS_WIDTH DT_INST_REG_SIZE(0) |
|
|
|
static int entropy_prbs_get_entropy(const struct device *dev, uint8_t *buffer, |
|
uint16_t length) |
|
{ |
|
while (length > 0) { |
|
size_t to_copy; |
|
uint32_t value; |
|
|
|
value = litex_read(PRBS_STATUS, PRBS_WIDTH); |
|
to_copy = MIN(length, sizeof(value)); |
|
|
|
memcpy(buffer, &value, to_copy); |
|
buffer += to_copy; |
|
length -= to_copy; |
|
} |
|
return 0; |
|
} |
|
|
|
static DEVICE_API(entropy, entropy_prbs_api) = { |
|
.get_entropy = entropy_prbs_get_entropy |
|
}; |
|
|
|
DEVICE_DT_INST_DEFINE(0, NULL, NULL, NULL, NULL, PRE_KERNEL_1, |
|
CONFIG_ENTROPY_INIT_PRIORITY, &entropy_prbs_api);
|
|
|