1 /*
2 * atmel_df_pow2.c - convert Atmel Dataflashes to Power of 2 mode
3 *
4 * Copyright 2009 Analog Devices Inc.
5 *
6 * Licensed under the 2-clause BSD.
7 */
8
9 #include <common.h>
10 #include <exports.h>
11 #include <spi.h>
12 #include <linux/delay.h>
13
14 #define CMD_ID 0x9f
15 #define CMD_STAT 0xd7
16 #define CMD_CFG 0x3d
17
flash_cmd(struct spi_slave * slave,uchar cmd,uchar * buf,int len)18 static int flash_cmd(struct spi_slave *slave, uchar cmd, uchar *buf, int len)
19 {
20 buf[0] = cmd;
21 return spi_xfer(slave, 8 * len, buf, buf, SPI_XFER_BEGIN | SPI_XFER_END);
22 }
23
flash_status(struct spi_slave * slave)24 static int flash_status(struct spi_slave *slave)
25 {
26 uchar buf[2];
27 if (flash_cmd(slave, CMD_STAT, buf, sizeof(buf)))
28 return -1;
29 return buf[1];
30 }
31
flash_set_pow2(struct spi_slave * slave)32 static int flash_set_pow2(struct spi_slave *slave)
33 {
34 int ret;
35 uchar buf[4];
36
37 buf[1] = 0x2a;
38 buf[2] = 0x80;
39 buf[3] = 0xa6;
40
41 ret = flash_cmd(slave, CMD_CFG, buf, sizeof(buf));
42 if (ret)
43 return ret;
44
45 /* wait Tp, or 6 msec */
46 udelay(6000);
47
48 ret = flash_status(slave);
49 if (ret == -1)
50 return 1;
51
52 return ret & 0x1 ? 0 : 1;
53 }
54
flash_check(struct spi_slave * slave)55 static int flash_check(struct spi_slave *slave)
56 {
57 int ret;
58 uchar buf[4];
59
60 ret = flash_cmd(slave, CMD_ID, buf, sizeof(buf));
61 if (ret)
62 return ret;
63
64 if (buf[1] != 0x1F) {
65 printf("atmel flash not found (id[0] = %#x)\n", buf[1]);
66 return 1;
67 }
68
69 if ((buf[2] >> 5) != 0x1) {
70 printf("AT45 flash not found (id[0] = %#x)\n", buf[2]);
71 return 2;
72 }
73
74 return 0;
75 }
76
getline(void)77 static char *getline(void)
78 {
79 static char buffer[100];
80 char c;
81 size_t i;
82
83 i = 0;
84 while (1) {
85 buffer[i] = '\0';
86
87 c = getc();
88
89 switch (c) {
90 case '\r': /* Enter/Return key */
91 case '\n':
92 puts("\n");
93 return buffer;
94
95 case 0x03: /* ^C - break */
96 return NULL;
97
98 case 0x5F:
99 case 0x08: /* ^H - backspace */
100 case 0x7F: /* DEL - backspace */
101 if (i) {
102 puts("\b \b");
103 i--;
104 }
105 break;
106
107 default:
108 /* Ignore control characters */
109 if (c < 0x20)
110 break;
111 /* Queue up all other characters */
112 buffer[i++] = c;
113 printf("%c", c);
114 break;
115 }
116 }
117 }
118
atmel_df_pow2(int argc,char * const argv[])119 int atmel_df_pow2(int argc, char *const argv[])
120 {
121 /* Print the ABI version */
122 app_startup(argv);
123 if (XF_VERSION != get_version()) {
124 printf("Expects ABI version %d\n", XF_VERSION);
125 printf("Actual U-Boot ABI version %lu\n", get_version());
126 printf("Can't run\n\n");
127 return 1;
128 }
129
130 while (1) {
131 struct spi_slave *slave;
132 char *line, *p;
133 int bus, cs, status;
134
135 puts("\nenter the [BUS:]CS of the SPI flash: ");
136 line = getline();
137
138 /* CTRL+C */
139 if (!line)
140 return 0;
141 if (line[0] == '\0')
142 continue;
143
144 bus = cs = simple_strtoul(line, &p, 10);
145 if (*p) {
146 if (*p == ':') {
147 ++p;
148 cs = simple_strtoul(p, &p, 10);
149 }
150 if (*p) {
151 puts("invalid format, please try again\n");
152 continue;
153 }
154 } else
155 bus = 0;
156
157 printf("\ngoing to work with dataflash at %i:%i\n", bus, cs);
158
159 /* use a low speed -- it'll work with all devices, and
160 * speed here doesn't really matter.
161 */
162 slave = spi_setup_slave(bus, cs, 1000, SPI_MODE_3);
163 if (!slave) {
164 puts("unable to setup slave\n");
165 continue;
166 }
167
168 if (spi_claim_bus(slave)) {
169 spi_free_slave(slave);
170 continue;
171 }
172
173 if (flash_check(slave)) {
174 puts("no flash found\n");
175 goto done;
176 }
177
178 status = flash_status(slave);
179 if (status == -1) {
180 puts("unable to read status register\n");
181 goto done;
182 }
183 if (status & 0x1) {
184 puts("flash is already in power-of-2 mode!\n");
185 goto done;
186 }
187
188 puts("are you sure you wish to set power-of-2 mode?\n");
189 puts("this operation is permanent and irreversible\n");
190 printf("enter YES to continue: ");
191 line = getline();
192 if (!line || strcmp(line, "YES"))
193 goto done;
194
195 if (flash_set_pow2(slave)) {
196 puts("setting pow2 mode failed\n");
197 goto done;
198 }
199
200 puts(
201 "Configuration should be updated now. You will have to\n"
202 "power cycle the part in order to finish the conversion.\n"
203 );
204
205 done:
206 spi_release_bus(slave);
207 spi_free_slave(slave);
208 }
209 }
210