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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/cris/arch-v10/drivers/axisflashmap.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/cris/arch-v10/drivers/axisflashmap.c')
-rw-r--r--arch/cris/arch-v10/drivers/axisflashmap.c541
1 files changed, 541 insertions, 0 deletions
diff --git a/arch/cris/arch-v10/drivers/axisflashmap.c b/arch/cris/arch-v10/drivers/axisflashmap.c
new file mode 100644
index 000000000000..fb7d4855ea62
--- /dev/null
+++ b/arch/cris/arch-v10/drivers/axisflashmap.c
@@ -0,0 +1,541 @@
1/*
2 * Physical mapping layer for MTD using the Axis partitiontable format
3 *
4 * Copyright (c) 2001, 2002 Axis Communications AB
5 *
6 * This file is under the GPL.
7 *
8 * First partition is always sector 0 regardless of if we find a partitiontable
9 * or not. In the start of the next sector, there can be a partitiontable that
10 * tells us what other partitions to define. If there isn't, we use a default
11 * partition split defined below.
12 *
13 * $Log: axisflashmap.c,v $
14 * Revision 1.10 2004/08/16 12:37:22 starvik
15 * Merge of Linux 2.6.8
16 *
17 * Revision 1.8 2004/05/14 07:58:03 starvik
18 * Merge of changes from 2.4
19 *
20 * Revision 1.6 2003/07/04 08:27:37 starvik
21 * Merge of Linux 2.5.74
22 *
23 * Revision 1.5 2002/12/11 13:13:57 starvik
24 * Added arch/ to v10 specific includes
25 * Added fix from Linux 2.4 in serial.c (flush_to_flip_buffer)
26 *
27 * Revision 1.4 2002/11/20 11:56:10 starvik
28 * Merge of Linux 2.5.48
29 *
30 * Revision 1.3 2002/11/13 14:54:13 starvik
31 * Copied from linux 2.4
32 *
33 * Revision 1.28 2002/10/01 08:08:43 jonashg
34 * The first partition ends at the start of the partition table.
35 *
36 * Revision 1.27 2002/08/21 09:23:13 jonashg
37 * Speling.
38 *
39 * Revision 1.26 2002/08/21 08:35:20 jonashg
40 * Cosmetic change to printouts.
41 *
42 * Revision 1.25 2002/08/21 08:15:42 jonashg
43 * Made it compile even without CONFIG_MTD_CONCAT defined.
44 *
45 * Revision 1.24 2002/08/20 13:12:35 jonashg
46 * * New approach to probing. Probe cse0 and cse1 separately and (mtd)concat
47 * the results.
48 * * Removed compile time tests concerning how the mtdram driver has been
49 * configured. The user will know about the misconfiguration at runtime
50 * instead. (The old approach made it impossible to use mtdram for anything
51 * else than RAM boot).
52 *
53 * Revision 1.23 2002/05/13 12:12:28 johana
54 * Allow compile without CONFIG_MTD_MTDRAM but warn at compiletime and
55 * be informative at runtime.
56 *
57 * Revision 1.22 2002/05/13 10:24:44 johana
58 * Added #if checks on MTDRAM CONFIG
59 *
60 * Revision 1.21 2002/05/06 16:05:20 johana
61 * Removed debug printout.
62 *
63 * Revision 1.20 2002/05/06 16:03:00 johana
64 * No more cramfs as root hack in generic code.
65 * It's handled by axisflashmap using mtdram.
66 *
67 * Revision 1.19 2002/03/15 17:10:28 bjornw
68 * Changed comment about cached access since we changed this before
69 *
70 * Revision 1.18 2002/03/05 17:06:15 jonashg
71 * Try amd_flash probe before cfi_probe since amd_flash driver can handle two
72 * (or more) flash chips of different model and the cfi driver cannot.
73 *
74 * Revision 1.17 2001/11/12 19:42:38 pkj
75 * Fixed compiler warnings.
76 *
77 * Revision 1.16 2001/11/08 11:18:58 jonashg
78 * Always read from uncached address to avoid problems with flushing
79 * cachelines after write and MTD-erase. No performance loss have been
80 * seen yet.
81 *
82 * Revision 1.15 2001/10/19 12:41:04 jonashg
83 * Name of probe has changed in MTD.
84 *
85 * Revision 1.14 2001/09/21 07:14:10 jonashg
86 * Made root filesystem (cramfs) use mtdblock driver when booting from flash.
87 *
88 * Revision 1.13 2001/08/15 13:57:35 jonashg
89 * Entire MTD updated to the linux 2.4.7 version.
90 *
91 * Revision 1.12 2001/06/11 09:50:30 jonashg
92 * Oops, 2MB is 0x200000 bytes.
93 *
94 * Revision 1.11 2001/06/08 11:39:44 jonashg
95 * Changed sizes and offsets in axis_default_partitions to use
96 * CONFIG_ETRAX_PTABLE_SECTOR.
97 *
98 * Revision 1.10 2001/05/29 09:42:03 jonashg
99 * Use macro for end marker length instead of sizeof.
100 *
101 * Revision 1.9 2001/05/29 08:52:52 jonashg
102 * Gave names to the magic fours (size of the ptable end marker).
103 *
104 * Revision 1.8 2001/05/28 15:36:20 jonashg
105 * * Removed old comment about ptable location in flash (it's a CONFIG_ option).
106 * * Variable ptable was initialized twice to the same value.
107 *
108 * Revision 1.7 2001/04/05 13:41:46 markusl
109 * Updated according to review remarks
110 *
111 * Revision 1.6 2001/03/07 09:21:21 bjornw
112 * No need to waste .data
113 *
114 * Revision 1.5 2001/03/06 16:27:01 jonashg
115 * Probe the entire flash area for flash devices.
116 *
117 * Revision 1.4 2001/02/23 12:47:15 bjornw
118 * Uncached flash in LOW_MAP moved from 0xe to 0x8
119 *
120 * Revision 1.3 2001/02/16 12:11:45 jonashg
121 * MTD driver amd_flash is now included in MTD CVS repository.
122 * (It's now in drivers/mtd).
123 *
124 * Revision 1.2 2001/02/09 11:12:22 jonashg
125 * Support for AMD compatible non-CFI flash chips.
126 * Only tested with Toshiba TC58FVT160 so far.
127 *
128 * Revision 1.1 2001/01/12 17:01:18 bjornw
129 * * Added axisflashmap.c, a physical mapping for MTD that reads and understands
130 * Axis partition-table format.
131 *
132 *
133 */
134
135#include <linux/module.h>
136#include <linux/types.h>
137#include <linux/kernel.h>
138#include <linux/config.h>
139#include <linux/init.h>
140
141#include <linux/mtd/concat.h>
142#include <linux/mtd/map.h>
143#include <linux/mtd/mtd.h>
144#include <linux/mtd/mtdram.h>
145#include <linux/mtd/partitions.h>
146
147#include <asm/axisflashmap.h>
148#include <asm/mmu.h>
149#include <asm/arch/sv_addr_ag.h>
150
151#ifdef CONFIG_CRIS_LOW_MAP
152#define FLASH_UNCACHED_ADDR KSEG_8
153#define FLASH_CACHED_ADDR KSEG_5
154#else
155#define FLASH_UNCACHED_ADDR KSEG_E
156#define FLASH_CACHED_ADDR KSEG_F
157#endif
158
159#if CONFIG_ETRAX_FLASH_BUSWIDTH==1
160#define flash_data __u8
161#elif CONFIG_ETRAX_FLASH_BUSWIDTH==2
162#define flash_data __u16
163#elif CONFIG_ETRAX_FLASH_BUSWIDTH==4
164#define flash_data __u16
165#endif
166
167/* From head.S */
168extern unsigned long romfs_start, romfs_length, romfs_in_flash;
169
170/* The master mtd for the entire flash. */
171struct mtd_info* axisflash_mtd = NULL;
172
173/* Map driver functions. */
174
175static map_word flash_read(struct map_info *map, unsigned long ofs)
176{
177 map_word tmp;
178 tmp.x[0] = *(flash_data *)(map->map_priv_1 + ofs);
179 return tmp;
180}
181
182static void flash_copy_from(struct map_info *map, void *to,
183 unsigned long from, ssize_t len)
184{
185 memcpy(to, (void *)(map->map_priv_1 + from), len);
186}
187
188static void flash_write(struct map_info *map, map_word d, unsigned long adr)
189{
190 *(flash_data *)(map->map_priv_1 + adr) = (flash_data)d.x[0];
191}
192
193/*
194 * The map for chip select e0.
195 *
196 * We run into tricky coherence situations if we mix cached with uncached
197 * accesses to we only use the uncached version here.
198 *
199 * The size field is the total size where the flash chips may be mapped on the
200 * chip select. MTD probes should find all devices there and it does not matter
201 * if there are unmapped gaps or aliases (mirrors of flash devices). The MTD
202 * probes will ignore them.
203 *
204 * The start address in map_priv_1 is in virtual memory so we cannot use
205 * MEM_CSE0_START but must rely on that FLASH_UNCACHED_ADDR is the start
206 * address of cse0.
207 */
208static struct map_info map_cse0 = {
209 .name = "cse0",
210 .size = MEM_CSE0_SIZE,
211 .bankwidth = CONFIG_ETRAX_FLASH_BUSWIDTH,
212 .read = flash_read,
213 .copy_from = flash_copy_from,
214 .write = flash_write,
215 .map_priv_1 = FLASH_UNCACHED_ADDR
216};
217
218/*
219 * The map for chip select e1.
220 *
221 * If there was a gap between cse0 and cse1, map_priv_1 would get the wrong
222 * address, but there isn't.
223 */
224static struct map_info map_cse1 = {
225 .name = "cse1",
226 .size = MEM_CSE1_SIZE,
227 .bankwidth = CONFIG_ETRAX_FLASH_BUSWIDTH,
228 .read = flash_read,
229 .copy_from = flash_copy_from,
230 .write = flash_write,
231 .map_priv_1 = FLASH_UNCACHED_ADDR + MEM_CSE0_SIZE
232};
233
234/* If no partition-table was found, we use this default-set. */
235#define MAX_PARTITIONS 7
236#define NUM_DEFAULT_PARTITIONS 3
237
238/*
239 * Default flash size is 2MB. CONFIG_ETRAX_PTABLE_SECTOR is most likely the
240 * size of one flash block and "filesystem"-partition needs 5 blocks to be able
241 * to use JFFS.
242 */
243static struct mtd_partition axis_default_partitions[NUM_DEFAULT_PARTITIONS] = {
244 {
245 .name = "boot firmware",
246 .size = CONFIG_ETRAX_PTABLE_SECTOR,
247 .offset = 0
248 },
249 {
250 .name = "kernel",
251 .size = 0x200000 - (6 * CONFIG_ETRAX_PTABLE_SECTOR),
252 .offset = CONFIG_ETRAX_PTABLE_SECTOR
253 },
254 {
255 .name = "filesystem",
256 .size = 5 * CONFIG_ETRAX_PTABLE_SECTOR,
257 .offset = 0x200000 - (5 * CONFIG_ETRAX_PTABLE_SECTOR)
258 }
259};
260
261/* Initialize the ones normally used. */
262static struct mtd_partition axis_partitions[MAX_PARTITIONS] = {
263 {
264 .name = "part0",
265 .size = CONFIG_ETRAX_PTABLE_SECTOR,
266 .offset = 0
267 },
268 {
269 .name = "part1",
270 .size = 0,
271 .offset = 0
272 },
273 {
274 .name = "part2",
275 .size = 0,
276 .offset = 0
277 },
278 {
279 .name = "part3",
280 .size = 0,
281 .offset = 0
282 },
283 {
284 .name = "part4",
285 .size = 0,
286 .offset = 0
287 },
288 {
289 .name = "part5",
290 .size = 0,
291 .offset = 0
292 },
293 {
294 .name = "part6",
295 .size = 0,
296 .offset = 0
297 },
298};
299
300/*
301 * Probe a chip select for AMD-compatible (JEDEC) or CFI-compatible flash
302 * chips in that order (because the amd_flash-driver is faster).
303 */
304static struct mtd_info *probe_cs(struct map_info *map_cs)
305{
306 struct mtd_info *mtd_cs = NULL;
307
308 printk(KERN_INFO
309 "%s: Probing a 0x%08lx bytes large window at 0x%08lx.\n",
310 map_cs->name, map_cs->size, map_cs->map_priv_1);
311
312#ifdef CONFIG_MTD_AMDSTD
313 mtd_cs = do_map_probe("amd_flash", map_cs);
314#endif
315#ifdef CONFIG_MTD_CFI
316 if (!mtd_cs) {
317 mtd_cs = do_map_probe("cfi_probe", map_cs);
318 }
319#endif
320
321 return mtd_cs;
322}
323
324/*
325 * Probe each chip select individually for flash chips. If there are chips on
326 * both cse0 and cse1, the mtd_info structs will be concatenated to one struct
327 * so that MTD partitions can cross chip boundries.
328 *
329 * The only known restriction to how you can mount your chips is that each
330 * chip select must hold similar flash chips. But you need external hardware
331 * to do that anyway and you can put totally different chips on cse0 and cse1
332 * so it isn't really much of a restriction.
333 */
334static struct mtd_info *flash_probe(void)
335{
336 struct mtd_info *mtd_cse0;
337 struct mtd_info *mtd_cse1;
338 struct mtd_info *mtd_cse;
339
340 mtd_cse0 = probe_cs(&map_cse0);
341 mtd_cse1 = probe_cs(&map_cse1);
342
343 if (!mtd_cse0 && !mtd_cse1) {
344 /* No chip found. */
345 return NULL;
346 }
347
348 if (mtd_cse0 && mtd_cse1) {
349#ifdef CONFIG_MTD_CONCAT
350 struct mtd_info *mtds[] = { mtd_cse0, mtd_cse1 };
351
352 /* Since the concatenation layer adds a small overhead we
353 * could try to figure out if the chips in cse0 and cse1 are
354 * identical and reprobe the whole cse0+cse1 window. But since
355 * flash chips are slow, the overhead is relatively small.
356 * So we use the MTD concatenation layer instead of further
357 * complicating the probing procedure.
358 */
359 mtd_cse = mtd_concat_create(mtds,
360 sizeof(mtds) / sizeof(mtds[0]),
361 "cse0+cse1");
362#else
363 printk(KERN_ERR "%s and %s: Cannot concatenate due to kernel "
364 "(mis)configuration!\n", map_cse0.name, map_cse1.name);
365 mtd_cse = NULL;
366#endif
367 if (!mtd_cse) {
368 printk(KERN_ERR "%s and %s: Concatenation failed!\n",
369 map_cse0.name, map_cse1.name);
370
371 /* The best we can do now is to only use what we found
372 * at cse0.
373 */
374 mtd_cse = mtd_cse0;
375 map_destroy(mtd_cse1);
376 }
377 } else {
378 mtd_cse = mtd_cse0? mtd_cse0 : mtd_cse1;
379 }
380
381 return mtd_cse;
382}
383
384/*
385 * Probe the flash chip(s) and, if it succeeds, read the partition-table
386 * and register the partitions with MTD.
387 */
388static int __init init_axis_flash(void)
389{
390 struct mtd_info *mymtd;
391 int err = 0;
392 int pidx = 0;
393 struct partitiontable_head *ptable_head = NULL;
394 struct partitiontable_entry *ptable;
395 int use_default_ptable = 1; /* Until proven otherwise. */
396 const char *pmsg = " /dev/flash%d at 0x%08x, size 0x%08x\n";
397
398 if (!(mymtd = flash_probe())) {
399 /* There's no reason to use this module if no flash chip can
400 * be identified. Make sure that's understood.
401 */
402 printk(KERN_INFO "axisflashmap: Found no flash chip.\n");
403 } else {
404 printk(KERN_INFO "%s: 0x%08x bytes of flash memory.\n",
405 mymtd->name, mymtd->size);
406 axisflash_mtd = mymtd;
407 }
408
409 if (mymtd) {
410 mymtd->owner = THIS_MODULE;
411 ptable_head = (struct partitiontable_head *)(FLASH_CACHED_ADDR +
412 CONFIG_ETRAX_PTABLE_SECTOR +
413 PARTITION_TABLE_OFFSET);
414 }
415 pidx++; /* First partition is always set to the default. */
416
417 if (ptable_head && (ptable_head->magic == PARTITION_TABLE_MAGIC)
418 && (ptable_head->size <
419 (MAX_PARTITIONS * sizeof(struct partitiontable_entry) +
420 PARTITIONTABLE_END_MARKER_SIZE))
421 && (*(unsigned long*)((void*)ptable_head + sizeof(*ptable_head) +
422 ptable_head->size -
423 PARTITIONTABLE_END_MARKER_SIZE)
424 == PARTITIONTABLE_END_MARKER)) {
425 /* Looks like a start, sane length and end of a
426 * partition table, lets check csum etc.
427 */
428 int ptable_ok = 0;
429 struct partitiontable_entry *max_addr =
430 (struct partitiontable_entry *)
431 ((unsigned long)ptable_head + sizeof(*ptable_head) +
432 ptable_head->size);
433 unsigned long offset = CONFIG_ETRAX_PTABLE_SECTOR;
434 unsigned char *p;
435 unsigned long csum = 0;
436
437 ptable = (struct partitiontable_entry *)
438 ((unsigned long)ptable_head + sizeof(*ptable_head));
439
440 /* Lets be PARANOID, and check the checksum. */
441 p = (unsigned char*) ptable;
442
443 while (p <= (unsigned char*)max_addr) {
444 csum += *p++;
445 csum += *p++;
446 csum += *p++;
447 csum += *p++;
448 }
449 ptable_ok = (csum == ptable_head->checksum);
450
451 /* Read the entries and use/show the info. */
452 printk(KERN_INFO " Found a%s partition table at 0x%p-0x%p.\n",
453 (ptable_ok ? " valid" : "n invalid"), ptable_head,
454 max_addr);
455
456 /* We have found a working bootblock. Now read the
457 * partition table. Scan the table. It ends when
458 * there is 0xffffffff, that is, empty flash.
459 */
460 while (ptable_ok
461 && ptable->offset != 0xffffffff
462 && ptable < max_addr
463 && pidx < MAX_PARTITIONS) {
464
465 axis_partitions[pidx].offset = offset + ptable->offset;
466 axis_partitions[pidx].size = ptable->size;
467
468 printk(pmsg, pidx, axis_partitions[pidx].offset,
469 axis_partitions[pidx].size);
470 pidx++;
471 ptable++;
472 }
473 use_default_ptable = !ptable_ok;
474 }
475
476 if (romfs_in_flash) {
477 /* Add an overlapping device for the root partition (romfs). */
478
479 axis_partitions[pidx].name = "romfs";
480 axis_partitions[pidx].size = romfs_length;
481 axis_partitions[pidx].offset = romfs_start - FLASH_CACHED_ADDR;
482 axis_partitions[pidx].mask_flags |= MTD_WRITEABLE;
483
484 printk(KERN_INFO
485 " Adding readonly flash partition for romfs image:\n");
486 printk(pmsg, pidx, axis_partitions[pidx].offset,
487 axis_partitions[pidx].size);
488 pidx++;
489 }
490
491 if (mymtd) {
492 if (use_default_ptable) {
493 printk(KERN_INFO " Using default partition table.\n");
494 err = add_mtd_partitions(mymtd, axis_default_partitions,
495 NUM_DEFAULT_PARTITIONS);
496 } else {
497 err = add_mtd_partitions(mymtd, axis_partitions, pidx);
498 }
499
500 if (err) {
501 panic("axisflashmap could not add MTD partitions!\n");
502 }
503 }
504
505 if (!romfs_in_flash) {
506 /* Create an RAM device for the root partition (romfs). */
507
508#if !defined(CONFIG_MTD_MTDRAM) || (CONFIG_MTDRAM_TOTAL_SIZE != 0) || (CONFIG_MTDRAM_ABS_POS != 0)
509 /* No use trying to boot this kernel from RAM. Panic! */
510 printk(KERN_EMERG "axisflashmap: Cannot create an MTD RAM "
511 "device due to kernel (mis)configuration!\n");
512 panic("This kernel cannot boot from RAM!\n");
513#else
514 struct mtd_info *mtd_ram;
515
516 mtd_ram = (struct mtd_info *)kmalloc(sizeof(struct mtd_info),
517 GFP_KERNEL);
518 if (!mtd_ram) {
519 panic("axisflashmap couldn't allocate memory for "
520 "mtd_info!\n");
521 }
522
523 printk(KERN_INFO " Adding RAM partition for romfs image:\n");
524 printk(pmsg, pidx, romfs_start, romfs_length);
525
526 err = mtdram_init_device(mtd_ram, (void*)romfs_start,
527 romfs_length, "romfs");
528 if (err) {
529 panic("axisflashmap could not initialize MTD RAM "
530 "device!\n");
531 }
532#endif
533 }
534
535 return err;
536}
537
538/* This adds the above to the kernels init-call chain. */
539module_init(init_axis_flash);
540
541EXPORT_SYMBOL(axisflash_mtd);