1 /*
2  * Copyright (C) 2017 PHYTEC Messtechnik GmbH
3  * Author: Wadim Egorov <w.egorov@phytec.de>
4  *
5  * SPDX-License-Identifier:     GPL-2.0+
6  */
7 
8 #include <asm/io.h>
9 #include <common.h>
10 #include <dm.h>
11 #include <environment.h>
12 #include <i2c.h>
13 #include <i2c_eeprom.h>
14 #include <netdev.h>
15 #include "som.h"
16 
17 static int valid_rk3288_som(struct rk3288_som *som)
18 {
19 	unsigned char *p = (unsigned char *)som;
20 	unsigned char *e = p + sizeof(struct rk3288_som) - 1;
21 	int hw = 0;
22 
23 	while (p < e) {
24 		hw += hweight8(*p);
25 		p++;
26 	}
27 
28 	return hw == som->bs;
29 }
30 
31 int rk_board_late_init(void)
32 {
33 	int ret;
34 	struct udevice *dev;
35 	struct rk3288_som opt;
36 	int off;
37 
38 	/* Get the identificatioin page of M24C32-D EEPROM */
39 	off = fdt_path_offset(gd->fdt_blob, "eeprom0");
40 	if (off < 0) {
41 		printf("%s: No eeprom0 path offset\n", __func__);
42 		return off;
43 	}
44 
45 	ret = uclass_get_device_by_of_offset(UCLASS_I2C_EEPROM, off, &dev);
46 	if (ret) {
47 		printf("%s: Could not find EEPROM\n", __func__);
48 		return ret;
49 	}
50 
51 	ret = i2c_set_chip_offset_len(dev, 2);
52 	if (ret)
53 		return ret;
54 
55 	ret = i2c_eeprom_read(dev, 0, (uint8_t *)&opt,
56 				sizeof(struct rk3288_som));
57 	if (ret) {
58 		printf("%s: Could not read EEPROM\n", __func__);
59 		return ret;
60 	}
61 
62 	if (opt.api_version != 0 || !valid_rk3288_som(&opt)) {
63 		printf("Invalid data or wrong EEPROM layout version.\n");
64 		/* Proceed anyway, since there is no fallback option */
65 	}
66 
67 	if (is_valid_ethaddr(opt.mac))
68 		eth_env_set_enetaddr("ethaddr", opt.mac);
69 
70 	return 0;
71 }
72