Free Electrons

Embedded Linux Experts

  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
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
/*
 *  Copyright (C) 2002 Benjamin Herrenschmidt (benh@kernel.crashing.org)
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version
 *  2 of the License, or (at your option) any later version.
 *
 *  Todo: - add support for the OF persistent properties
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/nvram.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/adb.h>
#include <linux/pmu.h>
#include <linux/bootmem.h>
#include <linux/completion.h>
#include <linux/spinlock.h>
#include <asm/sections.h>
#include <asm/io.h>
#include <asm/system.h>
#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/nvram.h>

#include "pmac.h"

#define DEBUG

#ifdef DEBUG
#define DBG(x...) printk(x)
#else
#define DBG(x...)
#endif

#define NVRAM_SIZE		0x2000	/* 8kB of non-volatile RAM */

#define CORE99_SIGNATURE	0x5a
#define CORE99_ADLER_START	0x14

/* On Core99, nvram is either a sharp, a micron or an AMD flash */
#define SM_FLASH_STATUS_DONE	0x80
#define SM_FLASH_STATUS_ERR	0x38

#define SM_FLASH_CMD_ERASE_CONFIRM	0xd0
#define SM_FLASH_CMD_ERASE_SETUP	0x20
#define SM_FLASH_CMD_RESET		0xff
#define SM_FLASH_CMD_WRITE_SETUP	0x40
#define SM_FLASH_CMD_CLEAR_STATUS	0x50
#define SM_FLASH_CMD_READ_STATUS	0x70

/* CHRP NVRAM header */
struct chrp_header {
  u8		signature;
  u8		cksum;
  u16		len;
  char          name[12];
  u8		data[0];
};

struct core99_header {
  struct chrp_header	hdr;
  u32			adler;
  u32			generation;
  u32			reserved[2];
};

/*
 * Read and write the non-volatile RAM on PowerMacs and CHRP machines.
 */
static int nvram_naddrs;
static volatile unsigned char __iomem *nvram_data;
static int is_core_99;
static int core99_bank = 0;
static int nvram_partitions[3];
// XXX Turn that into a sem
static DEFINE_SPINLOCK(nv_lock);

static int (*core99_write_bank)(int bank, u8* datas);
static int (*core99_erase_bank)(int bank);

static char *nvram_image;


static unsigned char core99_nvram_read_byte(int addr)
{
	if (nvram_image == NULL)
		return 0xff;
	return nvram_image[addr];
}

static void core99_nvram_write_byte(int addr, unsigned char val)
{
	if (nvram_image == NULL)
		return;
	nvram_image[addr] = val;
}

static ssize_t core99_nvram_read(char *buf, size_t count, loff_t *index)
{
	int i;

	if (nvram_image == NULL)
		return -ENODEV;
	if (*index > NVRAM_SIZE)
		return 0;

	i = *index;
	if (i + count > NVRAM_SIZE)
		count = NVRAM_SIZE - i;

	memcpy(buf, &nvram_image[i], count);
	*index = i + count;
	return count;
}

static ssize_t core99_nvram_write(char *buf, size_t count, loff_t *index)
{
	int i;

	if (nvram_image == NULL)
		return -ENODEV;
	if (*index > NVRAM_SIZE)
		return 0;

	i = *index;
	if (i + count > NVRAM_SIZE)
		count = NVRAM_SIZE - i;

	memcpy(&nvram_image[i], buf, count);
	*index = i + count;
	return count;
}

static ssize_t core99_nvram_size(void)
{
	if (nvram_image == NULL)
		return -ENODEV;
	return NVRAM_SIZE;
}

#ifdef CONFIG_PPC32
static volatile unsigned char __iomem *nvram_addr;
static int nvram_mult;

static unsigned char direct_nvram_read_byte(int addr)
{
	return in_8(&nvram_data[(addr & (NVRAM_SIZE - 1)) * nvram_mult]);
}

static void direct_nvram_write_byte(int addr, unsigned char val)
{
	out_8(&nvram_data[(addr & (NVRAM_SIZE - 1)) * nvram_mult], val);
}


static unsigned char indirect_nvram_read_byte(int addr)
{
	unsigned char val;
	unsigned long flags;

	spin_lock_irqsave(&nv_lock, flags);
	out_8(nvram_addr, addr >> 5);
	val = in_8(&nvram_data[(addr & 0x1f) << 4]);
	spin_unlock_irqrestore(&nv_lock, flags);

	return val;
}

static void indirect_nvram_write_byte(int addr, unsigned char val)
{
	unsigned long flags;

	spin_lock_irqsave(&nv_lock, flags);
	out_8(nvram_addr, addr >> 5);
	out_8(&nvram_data[(addr & 0x1f) << 4], val);
	spin_unlock_irqrestore(&nv_lock, flags);
}


#ifdef CONFIG_ADB_PMU

static void pmu_nvram_complete(struct adb_request *req)
{
	if (req->arg)
		complete((struct completion *)req->arg);
}

static unsigned char pmu_nvram_read_byte(int addr)
{
	struct adb_request req;
	DECLARE_COMPLETION_ONSTACK(req_complete);
	
	req.arg = system_state == SYSTEM_RUNNING ? &req_complete : NULL;
	if (pmu_request(&req, pmu_nvram_complete, 3, PMU_READ_NVRAM,
			(addr >> 8) & 0xff, addr & 0xff))
		return 0xff;
	if (system_state == SYSTEM_RUNNING)
		wait_for_completion(&req_complete);
	while (!req.complete)
		pmu_poll();
	return req.reply[0];
}

static void pmu_nvram_write_byte(int addr, unsigned char val)
{
	struct adb_request req;
	DECLARE_COMPLETION_ONSTACK(req_complete);
	
	req.arg = system_state == SYSTEM_RUNNING ? &req_complete : NULL;
	if (pmu_request(&req, pmu_nvram_complete, 4, PMU_WRITE_NVRAM,
			(addr >> 8) & 0xff, addr & 0xff, val))
		return;
	if (system_state == SYSTEM_RUNNING)
		wait_for_completion(&req_complete);
	while (!req.complete)
		pmu_poll();
}

#endif /* CONFIG_ADB_PMU */
#endif /* CONFIG_PPC32 */

static u8 chrp_checksum(struct chrp_header* hdr)
{
	u8 *ptr;
	u16 sum = hdr->signature;
	for (ptr = (u8 *)&hdr->len; ptr < hdr->data; ptr++)
		sum += *ptr;
	while (sum > 0xFF)
		sum = (sum & 0xFF) + (sum>>8);
	return sum;
}

static u32 core99_calc_adler(u8 *buffer)
{
	int cnt;
	u32 low, high;

   	buffer += CORE99_ADLER_START;
	low = 1;
	high = 0;
	for (cnt=0; cnt<(NVRAM_SIZE-CORE99_ADLER_START); cnt++) {
		if ((cnt % 5000) == 0) {
			high  %= 65521UL;
			high %= 65521UL;
		}
		low += buffer[cnt];
		high += low;
	}
	low  %= 65521UL;
	high %= 65521UL;

	return (high << 16) | low;
}

static u32 core99_check(u8* datas)
{
	struct core99_header* hdr99 = (struct core99_header*)datas;

	if (hdr99->hdr.signature != CORE99_SIGNATURE) {
		DBG("Invalid signature\n");
		return 0;
	}
	if (hdr99->hdr.cksum != chrp_checksum(&hdr99->hdr)) {
		DBG("Invalid checksum\n");
		return 0;
	}
	if (hdr99->adler != core99_calc_adler(datas)) {
		DBG("Invalid adler\n");
		return 0;
	}
	return hdr99->generation;
}

static int sm_erase_bank(int bank)
{
	int stat, i;
	unsigned long timeout;

	u8 __iomem *base = (u8 __iomem *)nvram_data + core99_bank*NVRAM_SIZE;

       	DBG("nvram: Sharp/Micron Erasing bank %d...\n", bank);

	out_8(base, SM_FLASH_CMD_ERASE_SETUP);
	out_8(base, SM_FLASH_CMD_ERASE_CONFIRM);
	timeout = 0;
	do {
		if (++timeout > 1000000) {
			printk(KERN_ERR "nvram: Sharp/Micron flash erase timeout !\n");
			break;
		}
		out_8(base, SM_FLASH_CMD_READ_STATUS);
		stat = in_8(base);
	} while (!(stat & SM_FLASH_STATUS_DONE));

	out_8(base, SM_FLASH_CMD_CLEAR_STATUS);
	out_8(base, SM_FLASH_CMD_RESET);

	for (i=0; i<NVRAM_SIZE; i++)
		if (base[i] != 0xff) {
			printk(KERN_ERR "nvram: Sharp/Micron flash erase failed !\n");
			return -ENXIO;
		}
	return 0;
}

static int sm_write_bank(int bank, u8* datas)
{
	int i, stat = 0;
	unsigned long timeout;

	u8 __iomem *base = (u8 __iomem *)nvram_data + core99_bank*NVRAM_SIZE;

       	DBG("nvram: Sharp/Micron Writing bank %d...\n", bank);

	for (i=0; i<NVRAM_SIZE; i++) {
		out_8(base+i, SM_FLASH_CMD_WRITE_SETUP);
		udelay(1);
		out_8(base+i, datas[i]);
		timeout = 0;
		do {
			if (++timeout > 1000000) {
				printk(KERN_ERR "nvram: Sharp/Micron flash write timeout !\n");
				break;
			}
			out_8(base, SM_FLASH_CMD_READ_STATUS);
			stat = in_8(base);
		} while (!(stat & SM_FLASH_STATUS_DONE));
		if (!(stat & SM_FLASH_STATUS_DONE))
			break;
	}
	out_8(base, SM_FLASH_CMD_CLEAR_STATUS);
	out_8(base, SM_FLASH_CMD_RESET);
	for (i=0; i<NVRAM_SIZE; i++)
		if (base[i] != datas[i]) {
			printk(KERN_ERR "nvram: Sharp/Micron flash write failed !\n");
			return -ENXIO;
		}
	return 0;
}

static int amd_erase_bank(int bank)
{
	int i, stat = 0;
	unsigned long timeout;

	u8 __iomem *base = (u8 __iomem *)nvram_data + core99_bank*NVRAM_SIZE;

       	DBG("nvram: AMD Erasing bank %d...\n", bank);

	/* Unlock 1 */
	out_8(base+0x555, 0xaa);
	udelay(1);
	/* Unlock 2 */
	out_8(base+0x2aa, 0x55);
	udelay(1);

	/* Sector-Erase */
	out_8(base+0x555, 0x80);
	udelay(1);
	out_8(base+0x555, 0xaa);
	udelay(1);
	out_8(base+0x2aa, 0x55);
	udelay(1);
	out_8(base, 0x30);
	udelay(1);

	timeout = 0;
	do {
		if (++timeout > 1000000) {
			printk(KERN_ERR "nvram: AMD flash erase timeout !\n");
			break;
		}
		stat = in_8(base) ^ in_8(base);
	} while (stat != 0);
	
	/* Reset */
	out_8(base, 0xf0);
	udelay(1);
	
	for (i=0; i<NVRAM_SIZE; i++)
		if (base[i] != 0xff) {
			printk(KERN_ERR "nvram: AMD flash erase failed !\n");
			return -ENXIO;
		}
	return 0;
}

static int amd_write_bank(int bank, u8* datas)
{
	int i, stat = 0;
	unsigned long timeout;

	u8 __iomem *base = (u8 __iomem *)nvram_data + core99_bank*NVRAM_SIZE;

       	DBG("nvram: AMD Writing bank %d...\n", bank);

	for (i=0; i<NVRAM_SIZE; i++) {
		/* Unlock 1 */
		out_8(base+0x555, 0xaa);
		udelay(1);
		/* Unlock 2 */
		out_8(base+0x2aa, 0x55);
		udelay(1);

		/* Write single word */
		out_8(base+0x555, 0xa0);
		udelay(1);
		out_8(base+i, datas[i]);
		
		timeout = 0;
		do {
			if (++timeout > 1000000) {
				printk(KERN_ERR "nvram: AMD flash write timeout !\n");
				break;
			}
			stat = in_8(base) ^ in_8(base);
		} while (stat != 0);
		if (stat != 0)
			break;
	}

	/* Reset */
	out_8(base, 0xf0);
	udelay(1);

	for (i=0; i<NVRAM_SIZE; i++)
		if (base[i] != datas[i]) {
			printk(KERN_ERR "nvram: AMD flash write failed !\n");
			return -ENXIO;
		}
	return 0;
}

static void __init lookup_partitions(void)
{
	u8 buffer[17];
	int i, offset;
	struct chrp_header* hdr;

	if (pmac_newworld) {
		nvram_partitions[pmac_nvram_OF] = -1;
		nvram_partitions[pmac_nvram_XPRAM] = -1;
		nvram_partitions[pmac_nvram_NR] = -1;
		hdr = (struct chrp_header *)buffer;

		offset = 0;
		buffer[16] = 0;
		do {
			for (i=0;i<16;i++)
				buffer[i] = ppc_md.nvram_read_val(offset+i);
			if (!strcmp(hdr->name, "common"))
				nvram_partitions[pmac_nvram_OF] = offset + 0x10;
			if (!strcmp(hdr->name, "APL,MacOS75")) {
				nvram_partitions[pmac_nvram_XPRAM] = offset + 0x10;
				nvram_partitions[pmac_nvram_NR] = offset + 0x110;
			}
			offset += (hdr->len * 0x10);
		} while(offset < NVRAM_SIZE);
	} else {
		nvram_partitions[pmac_nvram_OF] = 0x1800;
		nvram_partitions[pmac_nvram_XPRAM] = 0x1300;
		nvram_partitions[pmac_nvram_NR] = 0x1400;
	}
	DBG("nvram: OF partition at 0x%x\n", nvram_partitions[pmac_nvram_OF]);
	DBG("nvram: XP partition at 0x%x\n", nvram_partitions[pmac_nvram_XPRAM]);
	DBG("nvram: NR partition at 0x%x\n", nvram_partitions[pmac_nvram_NR]);
}

static void core99_nvram_sync(void)
{
	struct core99_header* hdr99;
	unsigned long flags;

	if (!is_core_99 || !nvram_data || !nvram_image)
		return;

	spin_lock_irqsave(&nv_lock, flags);
	if (!memcmp(nvram_image, (u8*)nvram_data + core99_bank*NVRAM_SIZE,
		NVRAM_SIZE))
		goto bail;

	DBG("Updating nvram...\n");

	hdr99 = (struct core99_header*)nvram_image;
	hdr99->generation++;
	hdr99->hdr.signature = CORE99_SIGNATURE;
	hdr99->hdr.cksum = chrp_checksum(&hdr99->hdr);
	hdr99->adler = core99_calc_adler(nvram_image);
	core99_bank = core99_bank ? 0 : 1;
	if (core99_erase_bank)
		if (core99_erase_bank(core99_bank)) {
			printk("nvram: Error erasing bank %d\n", core99_bank);
			goto bail;
		}
	if (core99_write_bank)
		if (core99_write_bank(core99_bank, nvram_image))
			printk("nvram: Error writing bank %d\n", core99_bank);
 bail:
	spin_unlock_irqrestore(&nv_lock, flags);

#ifdef DEBUG
       	mdelay(2000);
#endif
}

static int __init core99_nvram_setup(struct device_node *dp, unsigned long addr)
{
	int i;
	u32 gen_bank0, gen_bank1;

	if (nvram_naddrs < 1) {
		printk(KERN_ERR "nvram: no address\n");
		return -EINVAL;
	}
	nvram_image = alloc_bootmem(NVRAM_SIZE);
	if (nvram_image == NULL) {
		printk(KERN_ERR "nvram: can't allocate ram image\n");
		return -ENOMEM;
	}
	nvram_data = ioremap(addr, NVRAM_SIZE*2);
	nvram_naddrs = 1; /* Make sure we get the correct case */

	DBG("nvram: Checking bank 0...\n");

	gen_bank0 = core99_check((u8 *)nvram_data);
	gen_bank1 = core99_check((u8 *)nvram_data + NVRAM_SIZE);
	core99_bank = (gen_bank0 < gen_bank1) ? 1 : 0;

	DBG("nvram: gen0=%d, gen1=%d\n", gen_bank0, gen_bank1);
	DBG("nvram: Active bank is: %d\n", core99_bank);

	for (i=0; i<NVRAM_SIZE; i++)
		nvram_image[i] = nvram_data[i + core99_bank*NVRAM_SIZE];

	ppc_md.nvram_read_val	= core99_nvram_read_byte;
	ppc_md.nvram_write_val	= core99_nvram_write_byte;
	ppc_md.nvram_read	= core99_nvram_read;
	ppc_md.nvram_write	= core99_nvram_write;
	ppc_md.nvram_size	= core99_nvram_size;
	ppc_md.nvram_sync	= core99_nvram_sync;
	ppc_md.machine_shutdown	= core99_nvram_sync;
	/* 
	 * Maybe we could be smarter here though making an exclusive list
	 * of known flash chips is a bit nasty as older OF didn't provide us
	 * with a useful "compatible" entry. A solution would be to really
	 * identify the chip using flash id commands and base ourselves on
	 * a list of known chips IDs
	 */
	if (of_device_is_compatible(dp, "amd-0137")) {
		core99_erase_bank = amd_erase_bank;
		core99_write_bank = amd_write_bank;
	} else {
		core99_erase_bank = sm_erase_bank;
		core99_write_bank = sm_write_bank;
	}
	return 0;
}

int __init pmac_nvram_init(void)
{
	struct device_node *dp;
	struct resource r1, r2;
	unsigned int s1 = 0, s2 = 0;
	int err = 0;

	nvram_naddrs = 0;

	dp = of_find_node_by_name(NULL, "nvram");
	if (dp == NULL) {
		printk(KERN_ERR "Can't find NVRAM device\n");
		return -ENODEV;
	}

	/* Try to obtain an address */
	if (of_address_to_resource(dp, 0, &r1) == 0) {
		nvram_naddrs = 1;
		s1 = (r1.end - r1.start) + 1;
		if (of_address_to_resource(dp, 1, &r2) == 0) {
			nvram_naddrs = 2;
			s2 = (r2.end - r2.start) + 1;
		}
	}

	is_core_99 = of_device_is_compatible(dp, "nvram,flash");
	if (is_core_99) {
		err = core99_nvram_setup(dp, r1.start);
		goto bail;
	}

#ifdef CONFIG_PPC32
	if (machine_is(chrp) && nvram_naddrs == 1) {
		nvram_data = ioremap(r1.start, s1);
		nvram_mult = 1;
		ppc_md.nvram_read_val	= direct_nvram_read_byte;
		ppc_md.nvram_write_val	= direct_nvram_write_byte;
	} else if (nvram_naddrs == 1) {
		nvram_data = ioremap(r1.start, s1);
		nvram_mult = (s1 + NVRAM_SIZE - 1) / NVRAM_SIZE;
		ppc_md.nvram_read_val	= direct_nvram_read_byte;
		ppc_md.nvram_write_val	= direct_nvram_write_byte;
	} else if (nvram_naddrs == 2) {
		nvram_addr = ioremap(r1.start, s1);
		nvram_data = ioremap(r2.start, s2);
		ppc_md.nvram_read_val	= indirect_nvram_read_byte;
		ppc_md.nvram_write_val	= indirect_nvram_write_byte;
	} else if (nvram_naddrs == 0 && sys_ctrler == SYS_CTRLER_PMU) {
#ifdef CONFIG_ADB_PMU
		nvram_naddrs = -1;
		ppc_md.nvram_read_val	= pmu_nvram_read_byte;
		ppc_md.nvram_write_val	= pmu_nvram_write_byte;
#endif /* CONFIG_ADB_PMU */
	} else {
		printk(KERN_ERR "Incompatible type of NVRAM\n");
		err = -ENXIO;
	}
#endif /* CONFIG_PPC32 */
bail:
	of_node_put(dp);
	if (err == 0)
		lookup_partitions();
	return err;
}

int pmac_get_partition(int partition)
{
	return nvram_partitions[partition];
}

u8 pmac_xpram_read(int xpaddr)
{
	int offset = pmac_get_partition(pmac_nvram_XPRAM);

	if (offset < 0 || xpaddr < 0 || xpaddr > 0x100)
		return 0xff;

	return ppc_md.nvram_read_val(xpaddr + offset);
}

void pmac_xpram_write(int xpaddr, u8 data)
{
	int offset = pmac_get_partition(pmac_nvram_XPRAM);

	if (offset < 0 || xpaddr < 0 || xpaddr > 0x100)
		return;

	ppc_md.nvram_write_val(xpaddr + offset, data);
}

EXPORT_SYMBOL(pmac_get_partition);
EXPORT_SYMBOL(pmac_xpram_read);
EXPORT_SYMBOL(pmac_xpram_write);