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 <common.h>
10 #include <dm.h>
11 #include <linux/delay.h>
12 #include <linux/io.h>
13
14 #ifdef CONFIG_MISC_INIT_R
15
16 #define FU540_OTP_BASE_ADDR 0x10070000
17
18 struct fu540_otp_regs {
19 u32 pa; /* Address input */
20 u32 paio; /* Program address input */
21 u32 pas; /* Program redundancy cell selection input */
22 u32 pce; /* OTP Macro enable input */
23 u32 pclk; /* Clock input */
24 u32 pdin; /* Write data input */
25 u32 pdout; /* Read data output */
26 u32 pdstb; /* Deep standby mode enable input (active low) */
27 u32 pprog; /* Program mode enable input */
28 u32 ptc; /* Test column enable input */
29 u32 ptm; /* Test mode enable input */
30 u32 ptm_rep;/* Repair function test mode enable input */
31 u32 ptr; /* Test row enable input */
32 u32 ptrim; /* Repair function enable input */
33 u32 pwe; /* Write enable input (defines program cycle) */
34 } __packed;
35
36 #define BYTES_PER_FUSE 4
37 #define NUM_FUSES 0x1000
38
fu540_otp_read(int offset,void * buf,int size)39 static int fu540_otp_read(int offset, void *buf, int size)
40 {
41 struct fu540_otp_regs *regs = (void __iomem *)FU540_OTP_BASE_ADDR;
42 unsigned int i;
43 int fuseidx = offset / BYTES_PER_FUSE;
44 int fusecount = size / BYTES_PER_FUSE;
45 u32 fusebuf[fusecount];
46
47 /* check bounds */
48 if (offset < 0 || size < 0)
49 return -EINVAL;
50 if (fuseidx >= NUM_FUSES)
51 return -EINVAL;
52 if ((fuseidx + fusecount) > NUM_FUSES)
53 return -EINVAL;
54
55 /* init OTP */
56 writel(0x01, ®s->pdstb); /* wake up from stand-by */
57 writel(0x01, ®s->ptrim); /* enable repair function */
58 writel(0x01, ®s->pce); /* enable input */
59
60 /* read all requested fuses */
61 for (i = 0; i < fusecount; i++, fuseidx++) {
62 writel(fuseidx, ®s->pa);
63
64 /* cycle clock to read */
65 writel(0x01, ®s->pclk);
66 mdelay(1);
67 writel(0x00, ®s->pclk);
68 mdelay(1);
69
70 /* read the value */
71 fusebuf[i] = readl(®s->pdout);
72 }
73
74 /* shut down */
75 writel(0, ®s->pce);
76 writel(0, ®s->ptrim);
77 writel(0, ®s->pdstb);
78
79 /* copy out */
80 memcpy(buf, fusebuf, size);
81
82 return 0;
83 }
84
fu540_read_serialnum(void)85 static u32 fu540_read_serialnum(void)
86 {
87 int ret;
88 u32 serial[2] = {0};
89
90 for (int i = 0xfe * 4; i > 0; i -= 8) {
91 ret = fu540_otp_read(i, serial, sizeof(serial));
92 if (ret) {
93 printf("%s: error reading from OTP\n", __func__);
94 break;
95 }
96 if (serial[0] == ~serial[1])
97 return serial[0];
98 }
99
100 return 0;
101 }
102
fu540_setup_macaddr(u32 serialnum)103 static void fu540_setup_macaddr(u32 serialnum)
104 {
105 /* Default MAC address */
106 unsigned char mac[6] = { 0x70, 0xb3, 0xd5, 0x92, 0xf0, 0x00 };
107
108 /*
109 * We derive our board MAC address by ORing last three bytes
110 * of board serial number to above default MAC address.
111 *
112 * This logic of deriving board MAC address is taken from
113 * SiFive FSBL and is kept unchanged.
114 */
115 mac[5] |= (serialnum >> 0) & 0xff;
116 mac[4] |= (serialnum >> 8) & 0xff;
117 mac[3] |= (serialnum >> 16) & 0xff;
118
119 /* Update environment variable */
120 eth_env_set_enetaddr("ethaddr", mac);
121 }
122
misc_init_r(void)123 int misc_init_r(void)
124 {
125 u32 serial_num;
126 char buf[9] = {0};
127
128 /* Set ethaddr environment variable from board serial number */
129 if (!env_get("serial#")) {
130 serial_num = fu540_read_serialnum();
131 if (!serial_num) {
132 WARN(true, "Board serial number should not be 0 !!\n");
133 return 0;
134 }
135 snprintf(buf, sizeof(buf), "%08x", serial_num);
136 env_set("serial#", buf);
137 fu540_setup_macaddr(serial_num);
138 }
139 return 0;
140 }
141
142 #endif
143
board_init(void)144 int board_init(void)
145 {
146 /* For now nothing to do here. */
147
148 return 0;
149 }
150