board/CZ.NIC/turris_atsha_otp.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2017 Marek Behún <kabel@kernel.org>
   4  * Copyright (C) 2016 Tomas Hlavacek <tomas.hlavacek@nic.cz>
   5  */
   6
   7 #include <env.h>
   8 #include <net.h>
   9 #include <dm/device.h>
  10 #include <dm/uclass.h>
  11 #include <atsha204a-i2c.h>
  12
  13 #include "turris_atsha_otp.h"
  14
  15 #define TURRIS_ATSHA_OTP_VERSION        0
  16 #define TURRIS_ATSHA_OTP_SERIAL         1
  17 #define TURRIS_ATSHA_OTP_MAC0           3
  18 #define TURRIS_ATSHA_OTP_MAC1           4
  19
  20 extern U_BOOT_DRIVER(atsha204);
  21
  22 static struct udevice *get_atsha204a_dev(void)
  23 {
  24         /* Cannot be static because BSS does not have to be ready at this early stage */
  25         struct udevice *dev;
  26
  27         if (uclass_get_device_by_driver(UCLASS_MISC, DM_DRIVER_GET(atsha204), &dev)) {
  28                 puts("Cannot find ATSHA204A on I2C bus!\n");
  29                 dev = NULL;
  30         }
  31
  32         return dev;
  33 }
  34
  35 static void increment_mac(u8 *mac)
  36 {
  37         int i;
  38
  39         for (i = 5; i >= 3; i--) {
  40                 mac[i] += 1;
  41                 if (mac[i])
  42                         break;
  43         }
  44 }
  45
  46 static void set_mac_if_invalid(int i, u8 *mac)
  47 {
  48         u8 oldmac[6];
  49
  50         if (is_valid_ethaddr(mac) &&
  51             !eth_env_get_enetaddr_by_index("eth", i, oldmac))
  52                 eth_env_set_enetaddr_by_index("eth", i, mac);
  53 }
  54
  55 int turris_atsha_otp_init_mac_addresses(int first_idx)
  56 {
  57         struct udevice *dev = get_atsha204a_dev();
  58         u8 mac0[4], mac1[4], mac[6];
  59         int ret;
  60
  61         if (!dev)
  62                 return -1;
  63
  64         ret = atsha204a_wakeup(dev);
  65         if (ret)
  66                 return ret;
  67
  68         ret = atsha204a_read(dev, ATSHA204A_ZONE_OTP, false,
  69                              TURRIS_ATSHA_OTP_MAC0, mac0);
  70         if (ret)
  71                 return ret;
  72
  73         ret = atsha204a_read(dev, ATSHA204A_ZONE_OTP, false,
  74                              TURRIS_ATSHA_OTP_MAC1, mac1);
  75         if (ret)
  76                 return ret;
  77
  78         atsha204a_sleep(dev);
  79
  80         mac[0] = mac0[1];
  81         mac[1] = mac0[2];
  82         mac[2] = mac0[3];
  83         mac[3] = mac1[1];
  84         mac[4] = mac1[2];
  85         mac[5] = mac1[3];
  86
  87         set_mac_if_invalid((first_idx + 0) % 3, mac);
  88         increment_mac(mac);
  89         set_mac_if_invalid((first_idx + 1) % 3, mac);
  90         increment_mac(mac);
  91         set_mac_if_invalid((first_idx + 2) % 3, mac);
  92
  93         return 0;
  94 }
  95
  96 int turris_atsha_otp_get_serial_number(u32 *version_num, u32 *serial_num)
  97 {
  98         struct udevice *dev = get_atsha204a_dev();
  99         int ret;
 100
 101         if (!dev)
 102                 return -1;
 103
 104         ret = atsha204a_wakeup(dev);
 105         if (ret)
 106                 return ret;
 107
 108         ret = atsha204a_read(dev, ATSHA204A_ZONE_OTP, false,
 109                              TURRIS_ATSHA_OTP_VERSION,
 110                              (u8 *)version_num);
 111         if (ret)
 112                 return ret;
 113
 114         ret = atsha204a_read(dev, ATSHA204A_ZONE_OTP, false,
 115                              TURRIS_ATSHA_OTP_SERIAL,
 116                              (u8 *)serial_num);
 117         if (ret)
 118                 return ret;
 119
 120         atsha204a_sleep(dev);
 121         return 0;
 122 }