1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2019 Western Digital Corporation or its affiliates.
4  *
5  * Authors:
6  *   Anup Patel <anup.patel@wdc.com>
7  */
8 
9 #include <cpu_func.h>
10 #include <dm.h>
11 #include <env.h>
12 #include <init.h>
13 #include <log.h>
14 #include <linux/bitops.h>
15 #include <linux/bug.h>
16 #include <linux/delay.h>
17 #include <misc.h>
18 #include <spl.h>
19 #include <asm/sections.h>
20 
21 /*
22  * This define is a value used for error/unknown serial.
23  * If we really care about distinguishing errors and 0 is
24  * valid, we'll need a different one.
25  */
26 #define ERROR_READING_SERIAL_NUMBER       0
27 
28 #ifdef CONFIG_MISC_INIT_R
29 
30 #if IS_ENABLED(CONFIG_SIFIVE_OTP)
otp_read_serialnum(struct udevice * dev)31 static u32 otp_read_serialnum(struct udevice *dev)
32 {
33 	int ret;
34 	u32 serial[2] = {0};
35 
36 	for (int i = 0xfe * 4; i > 0; i -= 8) {
37 		ret = misc_read(dev, i, serial, sizeof(serial));
38 
39 		if (ret != sizeof(serial)) {
40 			printf("%s: error reading serial from OTP\n", __func__);
41 			break;
42 		}
43 
44 		if (serial[0] == ~serial[1])
45 			return serial[0];
46 	}
47 
48 	return ERROR_READING_SERIAL_NUMBER;
49 }
50 #endif
51 
fu540_read_serialnum(void)52 static u32 fu540_read_serialnum(void)
53 {
54 	u32 serial = ERROR_READING_SERIAL_NUMBER;
55 
56 #if IS_ENABLED(CONFIG_SIFIVE_OTP)
57 	struct udevice *dev;
58 	int ret;
59 
60 	/* init OTP */
61 	ret = uclass_get_device_by_driver(UCLASS_MISC,
62 					  DM_DRIVER_GET(sifive_otp), &dev);
63 
64 	if (ret) {
65 		debug("%s: could not find otp device\n", __func__);
66 		return serial;
67 	}
68 
69 	/* read serial from OTP and set env var */
70 	serial = otp_read_serialnum(dev);
71 #endif
72 
73 	return serial;
74 }
75 
fu540_setup_macaddr(u32 serialnum)76 static void fu540_setup_macaddr(u32 serialnum)
77 {
78 	/* Default MAC address */
79 	unsigned char mac[6] = { 0x70, 0xb3, 0xd5, 0x92, 0xf0, 0x00 };
80 
81 	/*
82 	 * We derive our board MAC address by ORing last three bytes
83 	 * of board serial number to above default MAC address.
84 	 *
85 	 * This logic of deriving board MAC address is taken from
86 	 * SiFive FSBL and is kept unchanged.
87 	 */
88 	mac[5] |= (serialnum >>  0) & 0xff;
89 	mac[4] |= (serialnum >>  8) & 0xff;
90 	mac[3] |= (serialnum >> 16) & 0xff;
91 
92 	/* Update environment variable */
93 	eth_env_set_enetaddr("ethaddr", mac);
94 }
95 
misc_init_r(void)96 int misc_init_r(void)
97 {
98 	u32 serial_num;
99 	char buf[9] = {0};
100 
101 	/* Set ethaddr environment variable from board serial number */
102 	if (!env_get("serial#")) {
103 		serial_num = fu540_read_serialnum();
104 		if (!serial_num) {
105 			WARN(true, "Board serial number should not be 0 !!\n");
106 			return 0;
107 		}
108 		snprintf(buf, sizeof(buf), "%08x", serial_num);
109 		env_set("serial#", buf);
110 		fu540_setup_macaddr(serial_num);
111 	}
112 	return 0;
113 }
114 
115 #endif
116 
board_init(void)117 int board_init(void)
118 {
119 	/* enable all cache ways */
120 	enable_caches();
121 
122 	return 0;
123 }
124