aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/brcm47xx/patches-3.2/0013-bcma-add-serial-flash-support-to-bcma.patch
blob: e78f3c4576392f22fdcb11f70d556f8a64b55944 (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
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
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
From a62940e988526c881966a8c72cc28c95fca89f3c Mon Sep 17 00:00:00 2001
From: Hauke Mehrtens <hauke@hauke-m.de>
Date: Sun, 17 Jul 2011 14:53:07 +0200
Subject: [PATCH 13/26] bcma: add serial flash support to bcma


Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
---
 drivers/bcma/Kconfig                        |    5 +
 drivers/bcma/Makefile                       |    1 +
 drivers/bcma/bcma_private.h                 |    5 +
 drivers/bcma/driver_chipcommon_sflash.c     |  555 +++++++++++++++++++++++++++
 drivers/bcma/driver_mips.c                  |    8 +-
 include/linux/bcma/bcma_driver_chipcommon.h |   24 ++
 6 files changed, 597 insertions(+), 1 deletions(-)
 create mode 100644 drivers/bcma/driver_chipcommon_sflash.c

--- a/drivers/bcma/Kconfig
+++ b/drivers/bcma/Kconfig
@@ -38,6 +38,11 @@ config BCMA_HOST_SOC
 	bool
 	depends on BCMA_DRIVER_MIPS
 
+config BCMA_SFLASH
+	bool
+	depends on BCMA_DRIVER_MIPS
+	default y
+
 config BCMA_DRIVER_MIPS
 	bool "BCMA Broadcom MIPS core driver"
 	depends on BCMA && MIPS
--- a/drivers/bcma/Makefile
+++ b/drivers/bcma/Makefile
@@ -1,5 +1,6 @@
 bcma-y					+= main.o scan.o core.o sprom.o
 bcma-y					+= driver_chipcommon.o driver_chipcommon_pmu.o
+bcma-$(CONFIG_BCMA_SFLASH)		+= driver_chipcommon_sflash.o
 bcma-y					+= driver_pci.o
 bcma-$(CONFIG_BCMA_DRIVER_PCI_HOSTMODE)	+= driver_pci_host.o
 bcma-$(CONFIG_BCMA_DRIVER_MIPS)		+= driver_mips.o
--- a/drivers/bcma/bcma_private.h
+++ b/drivers/bcma/bcma_private.h
@@ -41,6 +41,11 @@ void bcma_chipco_serial_init(struct bcma
 u32 bcma_pmu_alp_clock(struct bcma_drv_cc *cc);
 u32 bcma_pmu_get_clockcpu(struct bcma_drv_cc *cc);
 
+#ifdef CONFIG_BCMA_SFLASH
+/* driver_chipcommon_sflash.c */
+int bcma_sflash_init(struct bcma_drv_cc *cc);
+#endif /* CONFIG_BCMA_SFLASH */
+
 #ifdef CONFIG_BCMA_HOST_PCI
 /* host_pci.c */
 extern int __init bcma_host_pci_init(void);
--- /dev/null
+++ b/drivers/bcma/driver_chipcommon_sflash.c
@@ -0,0 +1,555 @@
+/*
+ * Broadcom SiliconBackplane chipcommon serial flash interface
+ *
+ * Copyright 2011, Jonas Gorski <jonas.gorski@gmail.com>
+ * Copyright 2010, Broadcom Corporation
+ *
+ * Licensed under the GNU/GPL. See COPYING for details.
+ */
+
+#include <linux/bcma/bcma.h>
+#include <linux/bcma/bcma_driver_chipcommon.h>
+#include <linux/delay.h>
+
+#include "bcma_private.h"
+
+#define NUM_RETRIES	3
+
+
+/* Issue a serial flash command */
+static inline void bcma_sflash_cmd(struct bcma_drv_cc *cc, u32 opcode)
+{
+	bcma_cc_write32(cc, BCMA_CC_FLASHCTL,
+			BCMA_CC_FLASHCTL_START | opcode);
+	while (bcma_cc_read32(cc, BCMA_CC_FLASHCTL) & BCMA_CC_FLASHCTL_BUSY)
+		;
+}
+
+
+static inline void bcma_sflash_write_u8(struct bcma_drv_cc *cc,
+					      u32 offset, u8 byte)
+{
+	bcma_cc_write32(cc, BCMA_CC_FLASHADDR, offset);
+	bcma_cc_write32(cc, BCMA_CC_FLASHDATA, byte);
+}
+
+/* Initialize serial flash access */
+int bcma_sflash_init(struct bcma_drv_cc *cc)
+{
+	u32 id, id2;
+
+	memset(&cc->sflash, 0, sizeof(struct bcma_sflash));
+
+	switch (cc->capabilities & BCMA_CC_CAP_FLASHT) {
+	case BCMA_CC_FLASHT_STSER:
+		/* Probe for ST chips */
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_DP);
+		bcma_cc_write32(cc, BCMA_CC_FLASHADDR, 0);
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_RES);
+		id = bcma_cc_read32(cc, BCMA_CC_FLASHDATA);
+		cc->sflash.blocksize = 64 * 1024;
+		switch (id) {
+		case 0x11:
+			/* ST M25P20 2 Mbit Serial Flash */
+			cc->sflash.numblocks = 4;
+			break;
+		case 0x12:
+			/* ST M25P40 4 Mbit Serial Flash */
+			cc->sflash.numblocks = 8;
+			break;
+		case 0x13:
+			/* ST M25P80 8 Mbit Serial Flash */
+			cc->sflash.numblocks = 16;
+			break;
+		case 0x14:
+			/* ST M25P16 16 Mbit Serial Flash */
+			cc->sflash.numblocks = 32;
+			break;
+		case 0x15:
+			/* ST M25P32 32 Mbit Serial Flash */
+			cc->sflash.numblocks = 64;
+			break;
+		case 0x16:
+			/* ST M25P64 64 Mbit Serial Flash */
+			cc->sflash.numblocks = 128;
+			break;
+		case 0x17:
+			/* ST M25FL128 128 Mbit Serial Flash */
+			cc->sflash.numblocks = 256;
+			break;
+		case 0xbf:
+			/* All of the following flashes are SST with
+			 * 4KB subsectors. Others should be added but
+			 * We'll have to revamp the way we identify them
+			 * since RES is not eough to disambiguate them.
+			 */
+			cc->sflash.blocksize = 4 * 1024;
+			bcma_cc_write32(cc, BCMA_CC_FLASHADDR, 1);
+			bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_RES);
+			id2 = bcma_cc_read32(cc, BCMA_CC_FLASHDATA);
+			switch (id2) {
+			case 1:
+				/* SST25WF512 512 Kbit Serial Flash */
+			case 0x48:
+				/* SST25VF512 512 Kbit Serial Flash */
+				cc->sflash.numblocks = 16;
+				break;
+			case 2:
+				/* SST25WF010 1 Mbit Serial Flash */
+			case 0x49:
+				/* SST25VF010 1 Mbit Serial Flash */
+				cc->sflash.numblocks = 32;
+				break;
+			case 3:
+				/* SST25WF020 2 Mbit Serial Flash */
+			case 0x43:
+				/* SST25VF020 2 Mbit Serial Flash */
+				cc->sflash.numblocks = 64;
+				break;
+			case 4:
+				/* SST25WF040 4 Mbit Serial Flash */
+			case 0x44:
+				/* SST25VF040 4 Mbit Serial Flash */
+			case 0x8d:
+				/* SST25VF040B 4 Mbit Serial Flash */
+				cc->sflash.numblocks = 128;
+				break;
+			case 5:
+				/* SST25WF080 8 Mbit Serial Flash */
+			case 0x8e:
+				/* SST25VF080B 8 Mbit Serial Flash */
+				cc->sflash.numblocks = 256;
+				break;
+			case 0x41:
+				/* SST25VF016 16 Mbit Serial Flash */
+				cc->sflash.numblocks = 512;
+				break;
+			case 0x4a:
+				/* SST25VF032 32 Mbit Serial Flash */
+				cc->sflash.numblocks = 1024;
+				break;
+			case 0x4b:
+				/* SST25VF064 64 Mbit Serial Flash */
+				cc->sflash.numblocks = 2048;
+				break;
+			}
+			break;
+		}
+		break;
+
+	case BCMA_CC_FLASHT_ATSER:
+		/* Probe for Atmel chips */
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_AT_STATUS);
+		id = bcma_cc_read32(cc, BCMA_CC_FLASHDATA) & 0x3c;
+		switch (id) {
+		case 0xc:
+			/* Atmel AT45DB011 1Mbit Serial Flash */
+			cc->sflash.blocksize = 256;
+			cc->sflash.numblocks = 512;
+			break;
+		case 0x14:
+			/* Atmel AT45DB021 2Mbit Serial Flash */
+			cc->sflash.blocksize = 256;
+			cc->sflash.numblocks = 1024;
+			break;
+		case 0x1c:
+			/* Atmel AT45DB041 4Mbit Serial Flash */
+			cc->sflash.blocksize = 256;
+			cc->sflash.numblocks = 2048;
+			break;
+		case 0x24:
+			/* Atmel AT45DB081 8Mbit Serial Flash */
+			cc->sflash.blocksize = 256;
+			cc->sflash.numblocks = 4096;
+			break;
+		case 0x2c:
+			/* Atmel AT45DB161 16Mbit Serial Flash */
+			cc->sflash.blocksize = 512;
+			cc->sflash.numblocks = 4096;
+			break;
+		case 0x34:
+			/* Atmel AT45DB321 32Mbit Serial Flash */
+			cc->sflash.blocksize = 512;
+			cc->sflash.numblocks = 8192;
+			break;
+		case 0x3c:
+			/* Atmel AT45DB642 64Mbit Serial Flash */
+			cc->sflash.blocksize = 1024;
+			cc->sflash.numblocks = 8192;
+			break;
+		}
+		break;
+	}
+
+	cc->sflash.size = cc->sflash.blocksize * cc->sflash.numblocks;
+
+	return cc->sflash.size ? 0 : -ENODEV;
+}
+
+/* Read len bytes starting at offset into buf. Returns number of bytes read. */
+int bcma_sflash_read(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			   u8 *buf)
+{
+	u8 *from, *to;
+	u32 cnt, i;
+
+	if (!len)
+		return 0;
+
+	if ((offset + len) > cc->sflash.size)
+		return -EINVAL;
+
+	if ((len >= 4) && (offset & 3))
+		cnt = 4 - (offset & 3);
+	else if ((len >= 4) && ((u32)buf & 3))
+		cnt = 4 - ((u32)buf & 3);
+	else
+		cnt = len;
+
+
+	if (cc->core->id.rev == 12)
+		from = (u8 *)KSEG1ADDR(BCMA_FLASH2 + offset);
+	else
+		from = (u8 *)KSEG0ADDR(BCMA_FLASH2 + offset);
+
+	to = (u8 *)buf;
+
+	if (cnt < 4) {
+		for (i = 0; i < cnt; i++) {
+			*to = readb(from);
+			from++;
+			to++;
+		}
+		return cnt;
+	}
+
+	while (cnt >= 4) {
+		*(u32 *)to = readl(from);
+		from += 4;
+		to += 4;
+		cnt -= 4;
+	}
+
+	return len - cnt;
+}
+
+/* Poll for command completion. Returns zero when complete. */
+int bcma_sflash_poll(struct bcma_drv_cc *cc, u32 offset)
+{
+	if (offset >= cc->sflash.size)
+		return -22;
+
+	switch (cc->capabilities & BCMA_CC_CAP_FLASHT) {
+	case BCMA_CC_FLASHT_STSER:
+		/* Check for ST Write In Progress bit */
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_RDSR);
+		return bcma_cc_read32(cc, BCMA_CC_FLASHDATA)
+				& BCMA_CC_FLASHDATA_ST_WIP;
+	case BCMA_CC_FLASHT_ATSER:
+		/* Check for Atmel Ready bit */
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_AT_STATUS);
+		return !(bcma_cc_read32(cc, BCMA_CC_FLASHDATA)
+				& BCMA_CC_FLASHDATA_AT_READY);
+	}
+
+	return 0;
+}
+
+
+static int sflash_st_write(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			   const u8 *buf)
+{
+	struct bcma_bus *bus = cc->core->bus;
+	int ret = 0;
+	bool is4712b0 = (bus->chipinfo.id == 0x4712) && (bus->chipinfo.rev == 3);
+	u32 mask;
+
+
+	/* Enable writes */
+	bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_WREN);
+	if (is4712b0) {
+		mask = 1 << 14;
+		bcma_sflash_write_u8(cc, offset, *buf++);
+		/* Set chip select */
+		bcma_cc_set32(cc, BCMA_CC_GPIOOUT, mask);
+		/* Issue a page program with the first byte */
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_PP);
+		ret = 1;
+		offset++;
+		len--;
+		while (len > 0) {
+			if ((offset & 255) == 0) {
+				/* Page boundary, drop cs and return */
+				bcma_cc_mask32(cc, BCMA_CC_GPIOOUT, ~mask);
+				udelay(1);
+				if (!bcma_sflash_poll(cc, offset)) {
+					/* Flash rejected command */
+					return -EAGAIN;
+				}
+				return ret;
+			} else {
+				/* Write single byte */
+				bcma_sflash_cmd(cc, *buf++);
+			}
+			ret++;
+			offset++;
+			len--;
+		}
+		/* All done, drop cs */
+		bcma_cc_mask32(cc, BCMA_CC_GPIOOUT, ~mask);
+		udelay(1);
+		if (!bcma_sflash_poll(cc, offset)) {
+			/* Flash rejected command */
+			return -EAGAIN;
+		}
+	} else if (cc->core->id.rev >= 20) {
+		bcma_sflash_write_u8(cc, offset, *buf++);
+		/* Issue a page program with CSA bit set */
+		bcma_sflash_cmd(cc,
+				BCMA_CC_FLASHCTL_ST_CSA |
+				BCMA_CC_FLASHCTL_ST_PP);
+		ret = 1;
+		offset++;
+		len--;
+		while (len > 0) {
+			if ((offset & 255) == 0) {
+				/* Page boundary, poll droping cs and return */
+				bcma_cc_write32(cc, BCMA_CC_FLASHCTL, 0);
+				udelay(1);
+				if (!bcma_sflash_poll(cc, offset)) {
+					/* Flash rejected command */
+					return -EAGAIN;
+				}
+				return ret;
+			} else {
+				/* Write single byte */
+				bcma_sflash_cmd(cc,
+						BCMA_CC_FLASHCTL_ST_CSA |
+						*buf++);
+			}
+			ret++;
+			offset++;
+			len--;
+		}
+		/* All done, drop cs & poll */
+		bcma_cc_write32(cc, BCMA_CC_FLASHCTL, 0);
+		udelay(1);
+		if (!bcma_sflash_poll(cc, offset)) {
+			/* Flash rejected command */
+			return -EAGAIN;
+		}
+	} else {
+		ret = 1;
+		bcma_sflash_write_u8(cc, offset, *buf);
+		/* Page program */
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_PP);
+	}
+	return ret;
+}
+
+static int sflash_at_write(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			   const u8 *buf)
+{
+	struct bcma_sflash *sfl = &cc->sflash;
+	u32 page, byte, mask;
+	int ret = 0;
+	mask = sfl->blocksize - 1;
+	page = (offset & ~mask) << 1;
+	byte = offset & mask;
+	/* Read main memory page into buffer 1 */
+	if (byte || (len < sfl->blocksize)) {
+		int i = 100;
+		bcma_cc_write32(cc, BCMA_CC_FLASHADDR, page);
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_AT_BUF1_LOAD);
+		/* 250 us for AT45DB321B */
+		while (i > 0 && bcma_sflash_poll(cc, offset)) {
+			udelay(10);
+			i--;
+		}
+		BUG_ON(!bcma_sflash_poll(cc, offset));
+	}
+	/* Write into buffer 1 */
+	for (ret = 0; (ret < (int)len) && (byte < sfl->blocksize); ret++) {
+		bcma_sflash_write_u8(cc, byte++, *buf++);
+		bcma_sflash_cmd(cc,
+				BCMA_CC_FLASHCTL_AT_BUF1_WRITE);
+	}
+	/* Write buffer 1 into main memory page */
+	bcma_cc_write32(cc, BCMA_CC_FLASHADDR, page);
+	bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_AT_BUF1_PROGRAM);
+
+	return ret;
+}
+
+/* Write len bytes starting at offset into buf. Returns number of bytes
+ * written. Caller should poll for completion.
+ */
+int bcma_sflash_write(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			    const u8 *buf)
+{
+	struct bcma_sflash *sfl;
+	int ret = 0, tries = NUM_RETRIES;
+
+	if (!len)
+		return 0;
+
+	if ((offset + len) > cc->sflash.size)
+		return -EINVAL;
+
+	sfl = &cc->sflash;
+	switch (cc->capabilities & BCMA_CC_CAP_FLASHT) {
+	case BCMA_CC_FLASHT_STSER:
+		do {
+			ret = sflash_st_write(cc, offset, len, buf);
+			tries--;
+		} while (ret == -EAGAIN && tries > 0);
+
+		if (ret == -EAGAIN && tries == 0) {
+			pr_info("ST Flash rejected write\n");
+			ret = -EIO;
+		}
+		break;
+	case BCMA_CC_FLASHT_ATSER:
+		ret = sflash_at_write(cc, offset, len, buf);
+		break;
+	}
+
+	return ret;
+}
+
+/* Erase a region. Returns number of bytes scheduled for erasure.
+ * Caller should poll for completion.
+ */
+int bcma_sflash_erase(struct bcma_drv_cc *cc, u32 offset)
+{
+	struct bcma_sflash *sfl;
+
+	if (offset >= cc->sflash.size)
+		return -EINVAL;
+
+	sfl = &cc->sflash;
+	switch (cc->capabilities & BCMA_CC_CAP_FLASHT) {
+	case BCMA_CC_FLASHT_STSER:
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_ST_WREN);
+		bcma_cc_write32(cc, BCMA_CC_FLASHADDR, offset);
+		/* Newer flashes have "sub-sectors" which can be erased independently
+		 * with a new command: ST_SSE. The ST_SE command erases 64KB just as
+		 * before.
+		 */
+		bcma_sflash_cmd(cc, (sfl->blocksize < (64 * 1024)) ? BCMA_CC_FLASHCTL_ST_SSE : BCMA_CC_FLASHCTL_ST_SE);
+		return sfl->blocksize;
+	case BCMA_CC_FLASHT_ATSER:
+		bcma_cc_write32(cc, BCMA_CC_FLASHADDR, offset << 1);
+		bcma_sflash_cmd(cc, BCMA_CC_FLASHCTL_AT_PAGE_ERASE);
+		return sfl->blocksize;
+	}
+
+	return 0;
+}
+
+/*
+ * writes the appropriate range of flash, a NULL buf simply erases
+ * the region of flash
+ */
+int bcma_sflash_commit(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			     const u8 *buf)
+{
+	struct bcma_sflash *sfl;
+	u8 *block = NULL, *cur_ptr, *blk_ptr;
+	u32 blocksize = 0, mask, cur_offset, cur_length, cur_retlen, remainder;
+	u32 blk_offset, blk_len, copied;
+	int bytes, ret = 0;
+
+	/* Check address range */
+	if (len <= 0)
+		return 0;
+
+	sfl = &cc->sflash;
+	if ((offset + len) > sfl->size)
+		return -EINVAL;
+
+	blocksize = sfl->blocksize;
+	mask = blocksize - 1;
+
+	/* Allocate a block of mem */
+	block = kmalloc(blocksize, GFP_KERNEL);
+	if (!block)
+		return -ENOMEM;
+
+	while (len) {
+		/* Align offset */
+		cur_offset = offset & ~mask;
+		cur_length = blocksize;
+		cur_ptr = block;
+
+		remainder = blocksize - (offset & mask);
+		if (len < remainder)
+			cur_retlen = len;
+		else
+			cur_retlen = remainder;
+
+		/* buf == NULL means erase only */
+		if (buf) {
+			/* Copy existing data into holding block if necessary */
+			if ((offset & mask) || (len < blocksize)) {
+				blk_offset = cur_offset;
+				blk_len = cur_length;
+				blk_ptr = cur_ptr;
+
+				/* Copy entire block */
+				while (blk_len) {
+					copied = bcma_sflash_read(cc,
+							blk_offset,
+							blk_len, blk_ptr);
+					blk_offset += copied;
+					blk_len -= copied;
+					blk_ptr += copied;
+				}
+			}
+
+			/* Copy input data into holding block */
+			memcpy(cur_ptr + (offset & mask), buf, cur_retlen);
+		}
+
+		/* Erase block */
+		ret = bcma_sflash_erase(cc, cur_offset);
+		if (ret < 0)
+			goto done;
+
+		while (bcma_sflash_poll(cc, cur_offset));
+
+		/* buf == NULL means erase only */
+		if (!buf) {
+			offset += cur_retlen;
+			len -= cur_retlen;
+			continue;
+		}
+
+		/* Write holding block */
+		while (cur_length > 0) {
+			bytes = bcma_sflash_write(cc, cur_offset,
+					cur_length, cur_ptr);
+
+			if (bytes < 0) {
+				ret = bytes;
+				goto done;
+			}
+
+			while (bcma_sflash_poll(cc, cur_offset))
+				;
+
+			cur_offset += bytes;
+			cur_length -= bytes;
+			cur_ptr += bytes;
+		}
+
+		offset += cur_retlen;
+		len -= cur_retlen;
+		buf += cur_retlen;
+	}
+
+	ret = len;
+done:
+	kfree(block);
+	return ret;
+}
--- a/drivers/bcma/driver_mips.c
+++ b/drivers/bcma/driver_mips.c
@@ -185,7 +185,13 @@ static void bcma_core_mips_flash_detect(
 	switch (bus->drv_cc.capabilities & BCMA_CC_CAP_FLASHT) {
 	case BCMA_CC_FLASHT_STSER:
 	case BCMA_CC_FLASHT_ATSER:
-		pr_err("Serial flash not supported.\n");
+#ifdef CONFIG_BCMA_SFLASH
+		pr_info("found serial flash.\n");
+		bus->drv_cc.flash_type = BCMA_SFLASH;
+		bcma_sflash_init(&bus->drv_cc);
+#else
+		pr_info("serial flash not supported.\n");
+#endif /* CONFIG_BCMA_SFLASH */
 		break;
 	case BCMA_CC_FLASHT_PARA:
 		pr_info("found parallel flash.\n");
--- a/include/linux/bcma/bcma_driver_chipcommon.h
+++ b/include/linux/bcma/bcma_driver_chipcommon.h
@@ -375,6 +375,7 @@ struct bcma_chipcommon_pmu {
 #ifdef CONFIG_BCMA_DRIVER_MIPS
 enum bcma_flash_type {
 	BCMA_PFLASH,
+	BCMA_SFLASH,
 };
 
 struct bcma_pflash {
@@ -383,6 +384,14 @@ struct bcma_pflash {
 	u32 window_size;
 };
 
+#ifdef CONFIG_BCMA_SFLASH
+struct bcma_sflash {
+	u32 blocksize;		/* Block size */
+	u32 numblocks;		/* Number of blocks */
+	u32 size;		/* Total size in bytes */
+};
+#endif /* CONFIG_BCMA_SFLASH */
+
 struct bcma_serial_port {
 	void *regs;
 	unsigned long clockspeed;
@@ -405,6 +414,9 @@ struct bcma_drv_cc {
 	enum bcma_flash_type flash_type;
 	union {
 		struct bcma_pflash pflash;
+#ifdef CONFIG_BCMA_SFLASH
+		struct bcma_sflash sflash;
+#endif /* CONFIG_BCMA_SFLASH */
 	};
 
 	int nr_serial_ports;
@@ -459,4 +471,16 @@ extern void bcma_chipco_chipctl_maskset(
 extern void bcma_chipco_regctl_maskset(struct bcma_drv_cc *cc,
 				       u32 offset, u32 mask, u32 set);
 
+#ifdef CONFIG_BCMA_SFLASH
+/* Chipcommon sflash support. */
+int bcma_sflash_read(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			   u8 *buf);
+int bcma_sflash_poll(struct bcma_drv_cc *cc, u32 offset);
+int bcma_sflash_write(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			    const u8 *buf);
+int bcma_sflash_erase(struct bcma_drv_cc *cc, u32 offset);
+int bcma_sflash_commit(struct bcma_drv_cc *cc, u32 offset, u32 len,
+			     const u8 *buf);
+#endif /* CONFIG_BCMA_SFLASH */
+
 #endif /* LINUX_BCMA_DRIVER_CC_H_ */