summaryrefslogtreecommitdiff
path: root/sys/dev/i2c/spdmem.c
blob: f4b8c5865be2fdf2705aee1be17a104df8b39334 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
/*	$OpenBSD: spdmem.c,v 1.26 2008/05/21 12:51:45 jsg Exp $	*/
/* $NetBSD: spdmem.c,v 1.3 2007/09/20 23:09:59 xtraeme Exp $ */

/*
 * Copyright (c) 2007 Jonathan Gray <jsg@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

/*
 * Copyright (c) 2007 Nicolas Joly
 * Copyright (c) 2007 Paul Goyette
 * Copyright (c) 2007 Tobias Nygren
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

/*
 * Serial Presence Detect (SPD) memory identification
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>

#include <dev/i2c/i2cvar.h>

/* possible values for the memory type */
#define	SPDMEM_MEMTYPE_FPM		0x01
#define	SPDMEM_MEMTYPE_EDO		0x02
#define	SPDMEM_MEMTYPE_PIPE_NIBBLE	0x03
#define	SPDMEM_MEMTYPE_SDRAM		0x04
#define	SPDMEM_MEMTYPE_ROM		0x05
#define	SPDMEM_MEMTYPE_DDRSGRAM		0x06
#define	SPDMEM_MEMTYPE_DDRSDRAM		0x07
#define	SPDMEM_MEMTYPE_DDR2SDRAM	0x08
#define	SPDMEM_MEMTYPE_NONE		0xff

#define SPDMEM_MEMTYPE_DIRECT_RAMBUS	0x01
#define SPDMEM_MEMTYPE_RAMBUS		0x11

/* possible values for the supply voltage */
#define	SPDMEM_VOLTAGE_TTL_5V		0x00
#define	SPDMEM_VOLTAGE_TTL_LV		0x01
#define	SPDMEM_VOLTAGE_HSTTL_1_5V	0x02
#define	SPDMEM_VOLTAGE_SSTL_3_3V	0x03
#define	SPDMEM_VOLTAGE_SSTL_2_5V	0x04
#define	SPDMEM_VOLTAGE_SSTL_1_8V	0x05

/* possible values for module configuration */
#define	SPDMEM_MODCONFIG_PARITY		0x01
#define	SPDMEM_MODCONFIG_ECC		0x02

/* for DDR2, module configuration is a bit-mask field */
#define	SPDMEM_MODCONFIG_HAS_DATA_PARITY	0x01
#define	SPDMEM_MODCONFIG_HAS_DATA_ECC		0x02
#define	SPDMEM_MODCONFIG_HAS_ADDR_CMD_PARITY	0x04

/* possible values for the refresh field */
#define	SPDMEM_REFRESH_STD		0x00
#define	SPDMEM_REFRESH_QUARTER		0x01
#define	SPDMEM_REFRESH_HALF		0x02
#define	SPDMEM_REFRESH_TWOX		0x03
#define	SPDMEM_REFRESH_FOURX		0x04
#define	SPDMEM_REFRESH_EIGHTX		0x05
#define	SPDMEM_REFRESH_SELFREFRESH	0x80

/* superset types */
#define	SPDMEM_SUPERSET_ESDRAM		0x01
#define	SPDMEM_SUPERSET_DDR_ESDRAM	0x02
#define	SPDMEM_SUPERSET_EDO_PEM		0x03
#define	SPDMEM_SUPERSET_SDR_PEM		0x04

/* FPM and EDO DIMMS */
#define SPDMEM_FPM_ROWS			0x00
#define SPDMEM_FPM_COLS			0x01
#define SPDMEM_FPM_BANKS		0x02
#define SPDMEM_FPM_CONFIG		0x08
#define SPDMEM_FPM_REFRESH		0x09
#define SPDMEM_FPM_SUPERSET		0x0c

/* PC66/PC100/PC133 SDRAM */
#define SPDMEM_SDR_ROWS			0x00
#define SPDMEM_SDR_COLS			0x01
#define SPDMEM_SDR_BANKS		0x02
#define SPDMEM_SDR_CYCLE		0x06
#define SPDMEM_SDR_BANKS_PER_CHIP	0x0e
#define SPDMEM_SDR_MOD_ATTRIB		0x12
#define SPDMEM_SDR_SUPERSET		0x1d

#define SPDMEM_SDR_FREQUENCY		126
#define SPDMEM_SDR_CAS			127
#define SPDMEM_SDR_FREQ_66		0x66
#define SPDMEM_SDR_FREQ_100		0x64
#define SPDMEM_SDR_FREQ_133		0x85
#define SPDMEM_SDR_CAS2			(1 << 1)
#define SPDMEM_SDR_CAS3			(1 << 2)

/* Rambus Direct DRAM */
#define SPDMEM_RDR_MODULE_TYPE		0x00
#define SPDMEM_RDR_ROWS_COLS		0x01
#define SPDMEM_RDR_BANK			0x02

#define SPDMEM_RDR_TYPE_RIMM		1
#define SPDMEM_RDR_TYPE_SORIMM		2
#define SPDMEM_RDR_TYPE_EMBED		3
#define SPDMEM_RDR_TYPE_RIMM32		4

/* Dual Data Rate SDRAM */
#define SPDMEM_DDR_ROWS			0x00
#define SPDMEM_DDR_COLS			0x01
#define SPDMEM_DDR_RANKS		0x02
#define SPDMEM_DDR_DATAWIDTH		0x03
#define SPDMEM_DDR_VOLTAGE		0x05
#define SPDMEM_DDR_CYCLE		0x06
#define SPDMEM_DDR_REFRESH		0x09
#define SPDMEM_DDR_BANKS_PER_CHIP	0x0e
#define SPDMEM_DDR_CAS			0x0f
#define SPDMEM_DDR_MOD_ATTRIB		0x12
#define SPDMEM_DDR_SUPERSET		0x1d

#define SPDMEM_DDR_ATTRIB_REG		(1 << 1)

/* Dual Data Rate 2 SDRAM */
#define SPDMEM_DDR2_ROWS		0x00
#define SPDMEM_DDR2_COLS		0x01
#define SPDMEM_DDR2_RANKS		0x02
#define SPDMEM_DDR2_DATAWIDTH		0x03
#define SPDMEM_DDR2_VOLTAGE		0x05
#define SPDMEM_DDR2_CYCLE		0x06
#define SPDMEM_DDR2_DIMMTYPE		0x11
#define SPDMEM_DDR2_RANK_DENSITY	0x1c

#define SPDMEM_DDR2_TYPE_REGMASK	((1 << 4) | (1 << 0))
#define SPDMEM_DDR2_SODIMM		(1 << 2)
#define SPDMEM_DDR2_MICRO_DIMM		(1 << 3)
#define SPDMEM_DDR2_MINI_RDIMM		(1 << 4)
#define SPDMEM_DDR2_MINI_UDIMM		(1 << 5)

static const uint8_t ddr2_cycle_tenths[] = {
	0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 25, 33, 66, 75, 0, 0
};

struct spdmem {
	uint8_t sm_len;
	uint8_t sm_size;
	uint8_t sm_type;
	uint8_t sm_data[60];
	uint8_t	sm_cksum;
} __packed;

#define SPDMEM_TYPE_MAXLEN 16
struct spdmem_softc {
	struct device	sc_dev;
	i2c_tag_t	sc_tag;
	i2c_addr_t	sc_addr;
	struct spdmem	sc_spd_data;
	char		sc_type[SPDMEM_TYPE_MAXLEN];
};

int		 spdmem_match(struct device *, void *, void *);
void		 spdmem_attach(struct device *, struct device *, void *);
uint8_t		 spdmem_read(struct spdmem_softc *, uint8_t);
void		 spdmem_sdram_decode(struct spdmem_softc *, struct spdmem *);
void		 spdmem_rdr_decode(struct spdmem_softc *, struct spdmem *);
void		 spdmem_ddr_decode(struct spdmem_softc *, struct spdmem *);
void		 spdmem_ddr2_decode(struct spdmem_softc *, struct spdmem *);

struct cfattach spdmem_ca = {
	sizeof(struct spdmem_softc), spdmem_match, spdmem_attach
};

struct cfdriver spdmem_cd = {
	NULL, "spdmem", DV_DULL
};

#define IS_RAMBUS_TYPE (s->sm_len < 4)

static const char *spdmem_basic_types[] = {
	"unknown",
	"FPM",
	"EDO",
	"Pipelined Nibble",
	"SDRAM",
	"ROM",
	"DDR SGRAM",
	"DDR SDRAM",
	"DDR2 SDRAM",
	"DDR2 SDRAM FB",
	"DDR2 SDRAM FB Probe"
};

static const char *spdmem_superset_types[] = {
	"unknown",
	"ESDRAM",
	"DDR ESDRAM",
	"PEM EDO",
	"PEM SDRAM"
};

static const char *spdmem_parity_types[] = {
	"non-parity",
	"data parity",
	"ECC",
	"data parity and ECC",
	"cmd/addr parity",
	"cmd/addr/data parity",
	"cmd/addr parity, data ECC",
	"cmd/addr/data parity, data ECC"
};

int
spdmem_match(struct device *parent, void *match, void *aux)
{
	struct i2c_attach_args *ia = aux;
	
	if (strcmp(ia->ia_name, "spd") == 0)
		return (1);
	return (0);
}

void
spdmem_sdram_decode(struct spdmem_softc *sc, struct spdmem *s)
{
	const char *type;
	int dimm_size, cycle_time, d_clk, p_clk, bits;
	int num_banks, per_chip;
	uint8_t config, rows, cols;

	type = spdmem_basic_types[s->sm_type];

	if (s->sm_data[SPDMEM_SDR_SUPERSET] == SPDMEM_SUPERSET_SDR_PEM)
		type = spdmem_superset_types[SPDMEM_SUPERSET_SDR_PEM];
	if (s->sm_data[SPDMEM_SDR_SUPERSET] == SPDMEM_SUPERSET_ESDRAM)
		type = spdmem_superset_types[SPDMEM_SUPERSET_ESDRAM];

	dimm_size = 0;

	num_banks = s->sm_data[SPDMEM_SDR_BANKS];
	per_chip = s->sm_data[SPDMEM_SDR_BANKS_PER_CHIP];
	rows = s->sm_data[SPDMEM_SDR_ROWS] & 0x0f;
	cols = s->sm_data[SPDMEM_SDR_COLS] & 0x0f;
	dimm_size = (1 << (rows + cols - 17)) * num_banks * per_chip;

	if (dimm_size > 0) {
		if (dimm_size < 1024)
			printf(" %dMB", dimm_size);
		else
			printf(" %dGB", dimm_size / 1024);
	}

	printf(" %s", type);
	strlcpy(sc->sc_type, type, SPDMEM_TYPE_MAXLEN);

	if (s->sm_data[SPDMEM_DDR_MOD_ATTRIB] & SPDMEM_DDR_ATTRIB_REG)
		printf(" registered");

	if (s->sm_data[SPDMEM_FPM_CONFIG] < 8)
		printf(" %s",
		    spdmem_parity_types[s->sm_data[SPDMEM_FPM_CONFIG]]);

	/* cycle_time is expressed in units of 0.01 ns */
	cycle_time = (s->sm_data[SPDMEM_DDR_CYCLE] >> 4) * 100 +
	    (s->sm_data[SPDMEM_DDR_CYCLE] & 0x0f) * 10;

	if (cycle_time != 0) {
		/*
		 * cycle time is scaled by a factor of 100 to avoid using
		 * floating point.  Calculate memory speed as the number
		 * of cycles per microsecond.
		 */
		d_clk = 100 * 1000;
		config = s->sm_data[SPDMEM_FPM_CONFIG];
		bits = s->sm_data[SPDMEM_DDR_DATAWIDTH] |
		    (s->sm_data[SPDMEM_DDR_DATAWIDTH + 1] << 8);
		if (config == 1 || config == 2)
			bits -= 8;

		p_clk = 66;
		if (s->sm_len >= 128) {
			switch (spdmem_read(sc, SPDMEM_SDR_FREQUENCY)) {
			case SPDMEM_SDR_FREQ_100:
			case SPDMEM_SDR_FREQ_133:
				/* We need to check ns to decide here */
				if (s->sm_data[SPDMEM_SDR_CYCLE] < 0x80)
					p_clk = 133;
				else
					p_clk = 100;
				break;
			case SPDMEM_SDR_FREQ_66:
			default:
				p_clk = 66;
				break;
			}
		}
		printf(" PC%d", p_clk);
	}

	/* Print CAS latency */
	if (s->sm_len < 128)
		return;
	if (spdmem_read(sc, SPDMEM_SDR_CAS) & SPDMEM_SDR_CAS2)
		printf("CL2");
	else if (spdmem_read(sc, SPDMEM_SDR_CAS) & SPDMEM_SDR_CAS3)
		printf("CL3");
}

void
spdmem_rdr_decode(struct spdmem_softc *sc, struct spdmem *s)
{
	int rimm_size;
	uint8_t row_bits, col_bits, bank_bits;

	row_bits = s->sm_data[SPDMEM_RDR_ROWS_COLS] >> 4;
	col_bits = s->sm_data[SPDMEM_RDR_ROWS_COLS] & 0x0f;
	bank_bits = s->sm_data[SPDMEM_RDR_BANK] & 0x07;

	/* subtracting 13 here is a cheaper way of dividing by 8k later */
	rimm_size = 1 << (row_bits + col_bits + bank_bits - 13);

	if (rimm_size < 1024)
		printf(" %dMB ", rimm_size);
	else
		printf(" %dGB ", rimm_size / 1024);

	switch(s->sm_data[SPDMEM_RDR_MODULE_TYPE]) {
	case SPDMEM_RDR_TYPE_RIMM:
		printf("RIMM");
		break;
	case SPDMEM_RDR_TYPE_SORIMM:
		printf("SO-RIMM");
		break;
	case SPDMEM_RDR_TYPE_EMBED:
		printf("Embedded Rambus");
		break;
	case SPDMEM_RDR_TYPE_RIMM32:
		printf("RIMM32");
		break;
	}
}

void
spdmem_ddr_decode(struct spdmem_softc *sc, struct spdmem *s)
{
	const char *type;
	int dimm_size, cycle_time, d_clk, p_clk, bits;
	int i, num_banks, per_chip;
	uint8_t config, rows, cols, cl;

	type = spdmem_basic_types[s->sm_type];

	if (s->sm_data[SPDMEM_DDR_SUPERSET] == SPDMEM_SUPERSET_DDR_ESDRAM)
		type = spdmem_superset_types[SPDMEM_SUPERSET_DDR_ESDRAM];

	dimm_size = 0;

	num_banks = s->sm_data[SPDMEM_SDR_BANKS];
	per_chip = s->sm_data[SPDMEM_SDR_BANKS_PER_CHIP];
	rows = s->sm_data[SPDMEM_SDR_ROWS] & 0x0f;
	cols = s->sm_data[SPDMEM_SDR_COLS] & 0x0f;
	dimm_size = (1 << (rows + cols - 17)) * num_banks * per_chip;

	if (dimm_size > 0) {
		if (dimm_size < 1024)
			printf(" %dMB", dimm_size);
		else
			printf(" %dGB", dimm_size / 1024);
	}

	printf(" %s", type);
	strlcpy(sc->sc_type, type, SPDMEM_TYPE_MAXLEN);

	if (s->sm_data[SPDMEM_DDR_MOD_ATTRIB] & SPDMEM_DDR_ATTRIB_REG)
		printf(" registered");

	if (s->sm_data[SPDMEM_FPM_CONFIG] < 8)
		printf(" %s",
		    spdmem_parity_types[s->sm_data[SPDMEM_FPM_CONFIG]]);

	/* cycle_time is expressed in units of 0.01 ns */
	cycle_time = (s->sm_data[SPDMEM_DDR_CYCLE] >> 4) * 100 +
	    (s->sm_data[SPDMEM_DDR_CYCLE] & 0x0f) * 10;

	if (cycle_time != 0) {
		/*
		 * cycle time is scaled by a factor of 100 to avoid using
		 * floating point.  Calculate memory speed as the number
		 * of cycles per microsecond.
		 * DDR2 uses dual-pumped clock
		 */
		d_clk = 100 * 1000 * 2;
		config = s->sm_data[SPDMEM_FPM_CONFIG];
		bits = s->sm_data[SPDMEM_DDR_DATAWIDTH] |
		    (s->sm_data[SPDMEM_DDR_DATAWIDTH + 1] << 8);
		if (config == 1 || config == 2)
			bits -= 8;

		d_clk /= cycle_time;
		p_clk = d_clk * bits / 8;
		if ((p_clk % 100) >= 50)
			p_clk += 50;
		p_clk -= p_clk % 100;
		printf(" PC%d", p_clk);
	}

	/* Print CAS latency */
	for (i = 6; i >= 0; i--) {
		if (s->sm_data[SPDMEM_DDR_CAS] & (1 << i)) {
			cl = ((i * 10) / 2) + 10;
			printf("CL%d.%d", cl / 10, cl % 10);
			break;
		}
	}
}

void
spdmem_ddr2_decode(struct spdmem_softc *sc, struct spdmem *s)
{
	const char *type;
	int dimm_size, cycle_time, d_clk, p_clk, bits;
	int i, num_ranks, density;
	uint8_t config;

	type = spdmem_basic_types[s->sm_type];

	dimm_size = 0;

	num_ranks = (s->sm_data[SPDMEM_DDR2_RANKS] & 0x7) + 1;
	density = (s->sm_data[SPDMEM_DDR2_RANK_DENSITY] & 0xf0) |
	    ((s->sm_data[SPDMEM_DDR2_RANK_DENSITY] & 0x0f) << 8);
	dimm_size = num_ranks * density * 4;

	if (dimm_size > 0) {
		if (dimm_size < 1024)
			printf(" %dMB", dimm_size);
		else
			printf(" %dGB", dimm_size / 1024);
	}

	printf(" %s", type);
	strlcpy(sc->sc_type, type, SPDMEM_TYPE_MAXLEN);

	if (s->sm_data[SPDMEM_DDR2_DIMMTYPE] & SPDMEM_DDR2_TYPE_REGMASK)
		printf(" registered");

	if (s->sm_data[SPDMEM_FPM_CONFIG] < 8)
		printf(" %s",
		    spdmem_parity_types[s->sm_data[SPDMEM_FPM_CONFIG]]);

	/* cycle_time is expressed in units of 0.01 ns */
	cycle_time = (s->sm_data[SPDMEM_DDR2_CYCLE] >> 4) * 100 +
	    ddr2_cycle_tenths[(s->sm_data[SPDMEM_DDR2_CYCLE] & 0x0f)];

	if (cycle_time != 0) {
		/*
		 * cycle time is scaled by a factor of 100 to avoid using
		 * floating point.  Calculate memory speed as the number
		 * of cycles per microsecond.
		 * DDR2 uses quad-pumped clock
		 */
		d_clk = 100 * 1000 * 4;
		config = s->sm_data[SPDMEM_FPM_CONFIG];
		bits = s->sm_data[SPDMEM_DDR2_DATAWIDTH];
		if ((config & 0x03) != 0)
			bits -= 8;
		d_clk /= cycle_time;
		d_clk = (d_clk + 1) / 2;
		p_clk = d_clk * bits / 8;
		p_clk -= p_clk % 100;
		printf(" PC2-%d", p_clk);
	}

	/* Print CAS latency */
	for (i = 5; i >= 2; i--) {
		if (s->sm_data[SPDMEM_DDR_CAS] & (i << i)) {
			printf("CL%d", i);
			break;
		}
	}

	switch (s->sm_data[SPDMEM_DDR2_DIMMTYPE]) {
	case SPDMEM_DDR2_SODIMM:
		printf(" SO-DIMM");
		break;
	case SPDMEM_DDR2_MICRO_DIMM:
		printf(" Micro-DIMM");
		break;
	case SPDMEM_DDR2_MINI_RDIMM:
	case SPDMEM_DDR2_MINI_UDIMM:
		printf(" Mini-DIMM");
		break;
	}
}

void
spdmem_attach(struct device *parent, struct device *self, void *aux)
{
	struct spdmem_softc *sc = (struct spdmem_softc *)self;
	struct i2c_attach_args *ia = aux;
	struct spdmem *s = &(sc->sc_spd_data);
	int i;

	sc->sc_tag = ia->ia_tag;
	sc->sc_addr = ia->ia_addr;

	printf(":");

	/* All SPD have at least 64 bytes of data including checksum */
	for (i = 0; i < 64; i++) {
		((uint8_t *)s)[i] = spdmem_read(sc, i);
	}

	/*
	 * Decode and print SPD contents
	 */
	if (s->sm_len < 4) {
		if (s->sm_type == SPDMEM_MEMTYPE_DIRECT_RAMBUS)
			spdmem_rdr_decode(sc, s);
		else
			printf(" no decode method for Rambus memory");
	} else {
		switch(s->sm_type) {
		case SPDMEM_MEMTYPE_EDO:
		case SPDMEM_MEMTYPE_SDRAM:
			spdmem_sdram_decode(sc, s);
			break;
		case SPDMEM_MEMTYPE_DDRSDRAM:
			spdmem_ddr_decode(sc, s);
			break;
		case SPDMEM_MEMTYPE_DDR2SDRAM:
			spdmem_ddr2_decode(sc, s);
			break;
		case SPDMEM_MEMTYPE_NONE:
			printf(" no EEPROM found");
			break;
		default:
			if (s->sm_type <= 10)
				printf(" no decode method for %s memory",
				    spdmem_basic_types[s->sm_type]);
			else
				printf(" unknown memory type %d", s->sm_type);
			break;
		}
	}

	printf("\n");
}

uint8_t
spdmem_read(struct spdmem_softc *sc, uint8_t reg)
{
	uint8_t val = 0xff;

	iic_acquire_bus(sc->sc_tag,0);
	iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr,
	    &reg, sizeof reg, &val, sizeof val, 0);
	iic_release_bus(sc->sc_tag, 0);

	return val;
}