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 <dm.h>
10 #include <env.h>
11 #include <init.h>
12 #include <log.h>
13 #include <linux/bitops.h>
14 #include <linux/bug.h>
15 #include <linux/delay.h>
16 #include <misc.h>
17 #include <spl.h>
18 #include <asm/arch/cache.h>
19 
20 /*
21  * This define is a value used for error/unknown serial.
22  * If we really care about distinguishing errors and 0 is
23  * valid, we'll need a different one.
24  */
25 #define ERROR_READING_SERIAL_NUMBER       0
26 
27 #ifdef CONFIG_MISC_INIT_R
28 
29 #if CONFIG_IS_ENABLED(SIFIVE_OTP)
otp_read_serialnum(struct udevice * dev)30 static u32 otp_read_serialnum(struct udevice *dev)
31 {
32 	int ret;
33 	u32 serial[2] = {0};
34 
35 	for (int i = 0xfe * 4; i > 0; i -= 8) {
36 		ret = misc_read(dev, i, serial, sizeof(serial));
37 
38 		if (ret != sizeof(serial)) {
39 			printf("%s: error reading serial from OTP\n", __func__);
40 			break;
41 		}
42 
43 		if (serial[0] == ~serial[1])
44 			return serial[0];
45 	}
46 
47 	return ERROR_READING_SERIAL_NUMBER;
48 }
49 #endif
50 
fu540_read_serialnum(void)51 static u32 fu540_read_serialnum(void)
52 {
53 	u32 serial = ERROR_READING_SERIAL_NUMBER;
54 
55 #if CONFIG_IS_ENABLED(SIFIVE_OTP)
56 	struct udevice *dev;
57 	int ret;
58 
59 	/* init OTP */
60 	ret = uclass_get_device_by_driver(UCLASS_MISC,
61 					  DM_DRIVER_GET(sifive_otp), &dev);
62 
63 	if (ret) {
64 		debug("%s: could not find otp device\n", __func__);
65 		return serial;
66 	}
67 
68 	/* read serial from OTP and set env var */
69 	serial = otp_read_serialnum(dev);
70 #endif
71 
72 	return serial;
73 }
74 
fu540_setup_macaddr(u32 serialnum)75 static void fu540_setup_macaddr(u32 serialnum)
76 {
77 	/* Default MAC address */
78 	unsigned char mac[6] = { 0x70, 0xb3, 0xd5, 0x92, 0xf0, 0x00 };
79 
80 	/*
81 	 * We derive our board MAC address by ORing last three bytes
82 	 * of board serial number to above default MAC address.
83 	 *
84 	 * This logic of deriving board MAC address is taken from
85 	 * SiFive FSBL and is kept unchanged.
86 	 */
87 	mac[5] |= (serialnum >>  0) & 0xff;
88 	mac[4] |= (serialnum >>  8) & 0xff;
89 	mac[3] |= (serialnum >> 16) & 0xff;
90 
91 	/* Update environment variable */
92 	eth_env_set_enetaddr("ethaddr", mac);
93 }
94 
misc_init_r(void)95 int misc_init_r(void)
96 {
97 	u32 serial_num;
98 	char buf[9] = {0};
99 
100 	/* Set ethaddr environment variable from board serial number */
101 	if (!env_get("serial#")) {
102 		serial_num = fu540_read_serialnum();
103 		if (!serial_num) {
104 			WARN(true, "Board serial number should not be 0 !!\n");
105 			return 0;
106 		}
107 		snprintf(buf, sizeof(buf), "%08x", serial_num);
108 		env_set("serial#", buf);
109 		fu540_setup_macaddr(serial_num);
110 	}
111 	return 0;
112 }
113 
114 #endif
115 
board_init(void)116 int board_init(void)
117 {
118 	int ret;
119 
120 	/* enable all cache ways */
121 	ret = cache_enable_ways();
122 	if (ret) {
123 		debug("%s: could not enable cache ways\n", __func__);
124 		return ret;
125 	}
126 
127 	return 0;
128 }
129