xref: /openbmc/u-boot/cmd/eeprom.c (revision cf4c34486d633c9e168475bd318ef67ff821063b)
1  /*
2   * (C) Copyright 2000, 2001
3   * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4   *
5   * SPDX-License-Identifier:	GPL-2.0+
6   */
7  
8  /*
9   * Support for read and write access to EEPROM like memory devices. This
10   * includes regular EEPROM as well as  FRAM (ferroelectic nonvolaile RAM).
11   * FRAM devices read and write data at bus speed. In particular, there is no
12   * write delay. Also, there is no limit imposed on the number of bytes that can
13   * be transferred with a single read or write.
14   *
15   * Use the following configuration options to ensure no unneeded performance
16   * degradation (typical for EEPROM) is incured for FRAM memory:
17   *
18   * #define CONFIG_SYS_I2C_FRAM
19   * #undef CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS
20   *
21   */
22  
23  #include <common.h>
24  #include <config.h>
25  #include <command.h>
26  #include <i2c.h>
27  #include <eeprom_layout.h>
28  
29  #ifndef	CONFIG_SYS_I2C_SPEED
30  #define	CONFIG_SYS_I2C_SPEED	50000
31  #endif
32  
33  #ifndef CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS
34  #define CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS	0
35  #endif
36  
37  #ifndef CONFIG_SYS_EEPROM_PAGE_WRITE_BITS
38  #define CONFIG_SYS_EEPROM_PAGE_WRITE_BITS	8
39  #endif
40  
41  #ifndef	I2C_RXTX_LEN
42  #define I2C_RXTX_LEN	128
43  #endif
44  
45  #define	EEPROM_PAGE_SIZE	(1 << CONFIG_SYS_EEPROM_PAGE_WRITE_BITS)
46  #define	EEPROM_PAGE_OFFSET(x)	((x) & (EEPROM_PAGE_SIZE - 1))
47  
48  /*
49   * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
50   *   0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
51   *
52   * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
53   *   0x00000nxx for EEPROM address selectors and page number at n.
54   */
55  #if !defined(CONFIG_SPI) || defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
56  #if !defined(CONFIG_SYS_I2C_EEPROM_ADDR_LEN) || \
57  	(CONFIG_SYS_I2C_EEPROM_ADDR_LEN < 1) || \
58  	(CONFIG_SYS_I2C_EEPROM_ADDR_LEN > 2)
59  #error CONFIG_SYS_I2C_EEPROM_ADDR_LEN must be 1 or 2
60  #endif
61  #endif
62  
63  __weak int eeprom_write_enable(unsigned dev_addr, int state)
64  {
65  	return 0;
66  }
67  
68  void eeprom_init(int bus)
69  {
70  	/* SPI EEPROM */
71  #if defined(CONFIG_SPI) && !defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
72  	spi_init_f();
73  #endif
74  
75  	/* I2C EEPROM */
76  #if defined(CONFIG_SYS_I2C)
77  	if (bus >= 0)
78  		i2c_set_bus_num(bus);
79  	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
80  #endif
81  }
82  
83  static int eeprom_addr(unsigned dev_addr, unsigned offset, uchar *addr)
84  {
85  	unsigned blk_off;
86  	int alen;
87  
88  	blk_off = offset & 0xff;	/* block offset */
89  #if CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1
90  	addr[0] = offset >> 8;		/* block number */
91  	addr[1] = blk_off;		/* block offset */
92  	alen = 2;
93  #else
94  	addr[0] = offset >> 16;		/* block number */
95  	addr[1] = offset >>  8;		/* upper address octet */
96  	addr[2] = blk_off;		/* lower address octet */
97  	alen = 3;
98  #endif	/* CONFIG_SYS_I2C_EEPROM_ADDR_LEN */
99  
100  	addr[0] |= dev_addr;		/* insert device address */
101  
102  	return alen;
103  }
104  
105  static int eeprom_len(unsigned offset, unsigned end)
106  {
107  	unsigned len = end - offset;
108  
109  	/*
110  	 * For a FRAM device there is no limit on the number of the
111  	 * bytes that can be ccessed with the single read or write
112  	 * operation.
113  	 */
114  #if !defined(CONFIG_SYS_I2C_FRAM)
115  	unsigned blk_off = offset & 0xff;
116  	unsigned maxlen = EEPROM_PAGE_SIZE - EEPROM_PAGE_OFFSET(blk_off);
117  
118  	if (maxlen > I2C_RXTX_LEN)
119  		maxlen = I2C_RXTX_LEN;
120  
121  	if (len > maxlen)
122  		len = maxlen;
123  #endif
124  
125  	return len;
126  }
127  
128  static int eeprom_rw_block(unsigned offset, uchar *addr, unsigned alen,
129  			   uchar *buffer, unsigned len, bool read)
130  {
131  	int ret = 0;
132  
133  	/* SPI */
134  #if defined(CONFIG_SPI) && !defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
135  	if (read)
136  		spi_read(addr, alen, buffer, len);
137  	else
138  		spi_write(addr, alen, buffer, len);
139  #else	/* I2C */
140  
141  #if defined(CONFIG_SYS_I2C_EEPROM_BUS)
142  	i2c_set_bus_num(CONFIG_SYS_I2C_EEPROM_BUS);
143  #endif
144  
145  	if (read)
146  		ret = i2c_read(addr[0], offset, alen - 1, buffer, len);
147  	else
148  		ret = i2c_write(addr[0], offset, alen - 1, buffer, len);
149  
150  	if (ret)
151  		ret = 1;
152  #endif
153  	return ret;
154  }
155  
156  static int eeprom_rw(unsigned dev_addr, unsigned offset, uchar *buffer,
157  		     unsigned cnt, bool read)
158  {
159  	unsigned end = offset + cnt;
160  	unsigned alen, len;
161  	int rcode = 0;
162  	uchar addr[3];
163  
164  	while (offset < end) {
165  		alen = eeprom_addr(dev_addr, offset, addr);
166  
167  		len = eeprom_len(offset, end);
168  
169  		rcode = eeprom_rw_block(offset, addr, alen, buffer, len, read);
170  
171  		buffer += len;
172  		offset += len;
173  
174  		if (!read)
175  			udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
176  	}
177  
178  	return rcode;
179  }
180  
181  int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
182  {
183  	/*
184  	 * Read data until done or would cross a page boundary.
185  	 * We must write the address again when changing pages
186  	 * because the next page may be in a different device.
187  	 */
188  	return eeprom_rw(dev_addr, offset, buffer, cnt, 1);
189  }
190  
191  int eeprom_write(unsigned dev_addr, unsigned offset,
192  		 uchar *buffer, unsigned cnt)
193  {
194  	int ret;
195  
196  	eeprom_write_enable(dev_addr, 1);
197  
198  	/*
199  	 * Write data until done or would cross a write page boundary.
200  	 * We must write the address again when changing pages
201  	 * because the address counter only increments within a page.
202  	 */
203  	ret = eeprom_rw(dev_addr, offset, buffer, cnt, 0);
204  
205  	eeprom_write_enable(dev_addr, 0);
206  	return ret;
207  }
208  
209  static int parse_numeric_param(char *str)
210  {
211  	char *endptr;
212  	int value = simple_strtol(str, &endptr, 16);
213  
214  	return (*endptr != '\0') ? -1 : value;
215  }
216  
217  /**
218   * parse_i2c_bus_addr - parse the i2c bus and i2c devaddr parameters
219   *
220   * @i2c_bus:	address to store the i2c bus
221   * @i2c_addr:	address to store the device i2c address
222   * @argc:	count of command line arguments left to parse
223   * @argv:	command line arguments left to parse
224   * @argc_no_bus_addr:	argc value we expect to see when bus & addr aren't given
225   *
226   * @returns:	number of arguments parsed or CMD_RET_USAGE if error
227   */
228  static int parse_i2c_bus_addr(int *i2c_bus, ulong *i2c_addr, int argc,
229  			      char * const argv[], int argc_no_bus_addr)
230  {
231  	int argc_no_bus = argc_no_bus_addr + 1;
232  	int argc_bus_addr = argc_no_bus_addr + 2;
233  
234  #ifdef CONFIG_SYS_DEF_EEPROM_ADDR
235  	if (argc == argc_no_bus_addr) {
236  		*i2c_bus = -1;
237  		*i2c_addr = CONFIG_SYS_DEF_EEPROM_ADDR;
238  
239  		return 0;
240  	}
241  #endif
242  	if (argc == argc_no_bus) {
243  		*i2c_bus = -1;
244  		*i2c_addr = parse_numeric_param(argv[0]);
245  
246  		return 1;
247  	}
248  
249  	if (argc == argc_bus_addr) {
250  		*i2c_bus = parse_numeric_param(argv[0]);
251  		*i2c_addr = parse_numeric_param(argv[1]);
252  
253  		return 2;
254  	}
255  
256  	return CMD_RET_USAGE;
257  }
258  
259  #ifdef CONFIG_CMD_EEPROM_LAYOUT
260  
261  __weak int eeprom_parse_layout_version(char *str)
262  {
263  	return LAYOUT_VERSION_UNRECOGNIZED;
264  }
265  
266  static unsigned char eeprom_buf[CONFIG_SYS_EEPROM_SIZE];
267  
268  #endif
269  
270  enum eeprom_action {
271  	EEPROM_READ,
272  	EEPROM_WRITE,
273  	EEPROM_PRINT,
274  	EEPROM_UPDATE,
275  	EEPROM_ACTION_INVALID,
276  };
277  
278  static enum eeprom_action parse_action(char *cmd)
279  {
280  	if (!strncmp(cmd, "read", 4))
281  		return EEPROM_READ;
282  	if (!strncmp(cmd, "write", 5))
283  		return EEPROM_WRITE;
284  #ifdef CONFIG_CMD_EEPROM_LAYOUT
285  	if (!strncmp(cmd, "print", 5))
286  		return EEPROM_PRINT;
287  	if (!strncmp(cmd, "update", 6))
288  		return EEPROM_UPDATE;
289  #endif
290  
291  	return EEPROM_ACTION_INVALID;
292  }
293  
294  static int eeprom_execute_command(enum eeprom_action action, int i2c_bus,
295  				  ulong i2c_addr, int layout_ver, char *key,
296  				  char *value, ulong addr, ulong off, ulong cnt)
297  {
298  	int rcode = 0;
299  	const char *const fmt =
300  		"\nEEPROM @0x%lX %s: addr %08lx  off %04lx  count %ld ... ";
301  #ifdef CONFIG_CMD_EEPROM_LAYOUT
302  	struct eeprom_layout layout;
303  #endif
304  
305  	if (action == EEPROM_ACTION_INVALID)
306  		return CMD_RET_USAGE;
307  
308  	eeprom_init(i2c_bus);
309  	if (action == EEPROM_READ) {
310  		printf(fmt, i2c_addr, "read", addr, off, cnt);
311  
312  		rcode = eeprom_read(i2c_addr, off, (uchar *)addr, cnt);
313  
314  		puts("done\n");
315  		return rcode;
316  	} else if (action == EEPROM_WRITE) {
317  		printf(fmt, i2c_addr, "write", addr, off, cnt);
318  
319  		rcode = eeprom_write(i2c_addr, off, (uchar *)addr, cnt);
320  
321  		puts("done\n");
322  		return rcode;
323  	}
324  
325  #ifdef CONFIG_CMD_EEPROM_LAYOUT
326  	rcode = eeprom_read(i2c_addr, 0, eeprom_buf, CONFIG_SYS_EEPROM_SIZE);
327  	if (rcode < 0)
328  		return rcode;
329  
330  	eeprom_layout_setup(&layout, eeprom_buf, CONFIG_SYS_EEPROM_SIZE,
331  			    layout_ver);
332  
333  	if (action == EEPROM_PRINT) {
334  		layout.print(&layout);
335  		return 0;
336  	}
337  
338  	layout.update(&layout, key, value);
339  
340  	rcode = eeprom_write(i2c_addr, 0, layout.data, CONFIG_SYS_EEPROM_SIZE);
341  #endif
342  
343  	return rcode;
344  }
345  
346  #define NEXT_PARAM(argc, index)	{ (argc)--; (index)++; }
347  int do_eeprom(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
348  {
349  	int layout_ver = LAYOUT_VERSION_AUTODETECT;
350  	enum eeprom_action action = EEPROM_ACTION_INVALID;
351  	int i2c_bus = -1, index = 0;
352  	ulong i2c_addr = -1, addr = 0, cnt = 0, off = 0;
353  	int ret;
354  	char *field_name = "";
355  	char *field_value = "";
356  
357  	if (argc <= 1)
358  		return CMD_RET_USAGE;
359  
360  	NEXT_PARAM(argc, index); /* Skip program name */
361  
362  	action = parse_action(argv[index]);
363  	NEXT_PARAM(argc, index);
364  
365  	if (action == EEPROM_ACTION_INVALID)
366  		return CMD_RET_USAGE;
367  
368  #ifdef CONFIG_CMD_EEPROM_LAYOUT
369  	if (action == EEPROM_PRINT || action == EEPROM_UPDATE) {
370  		if (!strcmp(argv[index], "-l")) {
371  			NEXT_PARAM(argc, index);
372  			layout_ver = eeprom_parse_layout_version(argv[index]);
373  			NEXT_PARAM(argc, index);
374  		}
375  	}
376  #endif
377  
378  	switch (action) {
379  	case EEPROM_READ:
380  	case EEPROM_WRITE:
381  		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
382  					 argv + index, 3);
383  		break;
384  	case EEPROM_PRINT:
385  		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
386  					 argv + index, 0);
387  		break;
388  	case EEPROM_UPDATE:
389  		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
390  					 argv + index, 2);
391  		break;
392  	default:
393  		/* Get compiler to stop whining */
394  		return CMD_RET_USAGE;
395  	}
396  
397  	if (ret == CMD_RET_USAGE)
398  		return ret;
399  
400  	while (ret--)
401  		NEXT_PARAM(argc, index);
402  
403  	if (action == EEPROM_READ || action == EEPROM_WRITE) {
404  		addr = parse_numeric_param(argv[index]);
405  		NEXT_PARAM(argc, index);
406  		off = parse_numeric_param(argv[index]);
407  		NEXT_PARAM(argc, index);
408  		cnt = parse_numeric_param(argv[index]);
409  	}
410  
411  #ifdef CONFIG_CMD_EEPROM_LAYOUT
412  	if (action == EEPROM_UPDATE) {
413  		field_name = argv[index];
414  		NEXT_PARAM(argc, index);
415  		field_value = argv[index];
416  		NEXT_PARAM(argc, index);
417  	}
418  #endif
419  
420  	return eeprom_execute_command(action, i2c_bus, i2c_addr, layout_ver,
421  				      field_name, field_value, addr, off, cnt);
422  }
423  
424  U_BOOT_CMD(
425  	eeprom,	8,	1,	do_eeprom,
426  	"EEPROM sub-system",
427  	"read  <bus> <devaddr> addr off cnt\n"
428  	"eeprom write <bus> <devaddr> addr off cnt\n"
429  	"       - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'"
430  #ifdef CONFIG_CMD_EEPROM_LAYOUT
431  	"\n"
432  	"eeprom print [-l <layout_version>] <bus> <devaddr>\n"
433  	"       - Print layout fields and their data in human readable format\n"
434  	"eeprom update [-l <layout_version>] <bus> <devaddr> field_name field_value\n"
435  	"       - Update a specific eeprom field with new data.\n"
436  	"         The new data must be written in the same human readable format as shown by the print command.\n"
437  	"\n"
438  	"LAYOUT VERSIONS\n"
439  	"The -l option can be used to force the command to interpret the EEPROM data using the chosen layout.\n"
440  	"If the -l option is omitted, the command will auto detect the layout based on the data in the EEPROM.\n"
441  	"The values which can be provided with the -l option are:\n"
442  	CONFIG_EEPROM_LAYOUT_HELP_STRING"\n"
443  #endif
444  )
445