blob: 767a3840d64d30f07f47c8f6a6d8f258e1b6f8e1 [file] [log] [blame]
/*
* 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/zephyr.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 int entropy_prbs_init(const struct device *dev)
{
return 0;
}
static const struct entropy_driver_api entropy_prbs_api = {
.get_entropy = entropy_prbs_get_entropy
};
DEVICE_DT_INST_DEFINE(0,
entropy_prbs_init, NULL, NULL, NULL,
PRE_KERNEL_1, CONFIG_ENTROPY_INIT_PRIORITY,
&entropy_prbs_api);