blob: eaa9fa813cc549a6204e45d5841669274bdbe5ea [file] [log] [blame]
/*
* Copyright (c) 2019 Leandro A. F. Pereira
* Copyright (c) 2020 Nordic Semiconductor ASA
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <soc/efuse_reg.h>
#include <drivers/hwinfo.h>
#include <string.h>
ssize_t z_impl_hwinfo_get_device_id(uint8_t *buffer, size_t length)
{
uint32_t rdata1 = sys_read32(EFUSE_BLK0_RDATA1_REG);
uint32_t rdata2 = sys_read32(EFUSE_BLK0_RDATA2_REG);
uint8_t id[6];
/* The first word provides the lower 32 bits of the MAC
* address; the low 16 bits of the second word provide the
* upper 16 bytes of the MAC address. The upper 16 bits are
* (apparently) a checksum, and reserved. See ESP32 Technical
* Reference Manual V4.1 section 20.5.
*/
id[0] = (uint8_t)(rdata2 >> 8);
id[1] = (uint8_t)(rdata2 >> 0);
id[2] = (uint8_t)(rdata1 >> 24);
id[3] = (uint8_t)(rdata1 >> 16);
id[4] = (uint8_t)(rdata1 >> 8);
id[5] = (uint8_t)(rdata1 >> 0);
if (length > sizeof(id)) {
length = sizeof(id);
}
memcpy(buffer, id, length);
return length;
}