Linux 2.6.26-rc5
[linux-2.6/openmoko-kernel/knife-kernel.git] / arch / cris / arch-v32 / drivers / axisflashmap.c
blob51e1e85df96d5407940c0376e28158724f9c5cb1
1 /*
2 * Physical mapping layer for MTD using the Axis partitiontable format
4 * Copyright (c) 2001-2007 Axis Communications AB
6 * This file is under the GPL.
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.
15 #include <linux/module.h>
16 #include <linux/types.h>
17 #include <linux/kernel.h>
18 #include <linux/init.h>
19 #include <linux/slab.h>
21 #include <linux/mtd/concat.h>
22 #include <linux/mtd/map.h>
23 #include <linux/mtd/mtd.h>
24 #include <linux/mtd/mtdram.h>
25 #include <linux/mtd/partitions.h>
27 #include <linux/cramfs_fs.h>
29 #include <asm/axisflashmap.h>
30 #include <asm/mmu.h>
32 #define MEM_CSE0_SIZE (0x04000000)
33 #define MEM_CSE1_SIZE (0x04000000)
35 #define FLASH_UNCACHED_ADDR KSEG_E
36 #define FLASH_CACHED_ADDR KSEG_F
38 #define PAGESIZE (512)
40 #if CONFIG_ETRAX_FLASH_BUSWIDTH==1
41 #define flash_data __u8
42 #elif CONFIG_ETRAX_FLASH_BUSWIDTH==2
43 #define flash_data __u16
44 #elif CONFIG_ETRAX_FLASH_BUSWIDTH==4
45 #define flash_data __u32
46 #endif
48 /* From head.S */
49 extern unsigned long romfs_in_flash; /* 1 when romfs_start, _length in flash */
50 extern unsigned long romfs_start, romfs_length;
51 extern unsigned long nand_boot; /* 1 when booted from nand flash */
53 struct partition_name {
54 char name[6];
57 /* The master mtd for the entire flash. */
58 struct mtd_info* axisflash_mtd = NULL;
60 /* Map driver functions. */
62 static map_word flash_read(struct map_info *map, unsigned long ofs)
64 map_word tmp;
65 tmp.x[0] = *(flash_data *)(map->map_priv_1 + ofs);
66 return tmp;
69 static void flash_copy_from(struct map_info *map, void *to,
70 unsigned long from, ssize_t len)
72 memcpy(to, (void *)(map->map_priv_1 + from), len);
75 static void flash_write(struct map_info *map, map_word d, unsigned long adr)
77 *(flash_data *)(map->map_priv_1 + adr) = (flash_data)d.x[0];
81 * The map for chip select e0.
83 * We run into tricky coherence situations if we mix cached with uncached
84 * accesses to we only use the uncached version here.
86 * The size field is the total size where the flash chips may be mapped on the
87 * chip select. MTD probes should find all devices there and it does not matter
88 * if there are unmapped gaps or aliases (mirrors of flash devices). The MTD
89 * probes will ignore them.
91 * The start address in map_priv_1 is in virtual memory so we cannot use
92 * MEM_CSE0_START but must rely on that FLASH_UNCACHED_ADDR is the start
93 * address of cse0.
95 static struct map_info map_cse0 = {
96 .name = "cse0",
97 .size = MEM_CSE0_SIZE,
98 .bankwidth = CONFIG_ETRAX_FLASH_BUSWIDTH,
99 .read = flash_read,
100 .copy_from = flash_copy_from,
101 .write = flash_write,
102 .map_priv_1 = FLASH_UNCACHED_ADDR
106 * The map for chip select e1.
108 * If there was a gap between cse0 and cse1, map_priv_1 would get the wrong
109 * address, but there isn't.
111 static struct map_info map_cse1 = {
112 .name = "cse1",
113 .size = MEM_CSE1_SIZE,
114 .bankwidth = CONFIG_ETRAX_FLASH_BUSWIDTH,
115 .read = flash_read,
116 .copy_from = flash_copy_from,
117 .write = flash_write,
118 .map_priv_1 = FLASH_UNCACHED_ADDR + MEM_CSE0_SIZE
121 #define MAX_PARTITIONS 7
122 #ifdef CONFIG_ETRAX_NANDBOOT
123 #define NUM_DEFAULT_PARTITIONS 4
124 #define DEFAULT_ROOTFS_PARTITION_NO 2
125 #define DEFAULT_MEDIA_SIZE 0x2000000 /* 32 megs */
126 #else
127 #define NUM_DEFAULT_PARTITIONS 3
128 #define DEFAULT_ROOTFS_PARTITION_NO (-1)
129 #define DEFAULT_MEDIA_SIZE 0x800000 /* 8 megs */
130 #endif
132 #if (MAX_PARTITIONS < NUM_DEFAULT_PARTITIONS)
133 #error MAX_PARTITIONS must be >= than NUM_DEFAULT_PARTITIONS
134 #endif
136 /* Initialize the ones normally used. */
137 static struct mtd_partition axis_partitions[MAX_PARTITIONS] = {
139 .name = "part0",
140 .size = CONFIG_ETRAX_PTABLE_SECTOR,
141 .offset = 0
144 .name = "part1",
145 .size = 0,
146 .offset = 0
149 .name = "part2",
150 .size = 0,
151 .offset = 0
154 .name = "part3",
155 .size = 0,
156 .offset = 0
159 .name = "part4",
160 .size = 0,
161 .offset = 0
164 .name = "part5",
165 .size = 0,
166 .offset = 0
169 .name = "part6",
170 .size = 0,
171 .offset = 0
176 /* If no partition-table was found, we use this default-set.
177 * Default flash size is 8MB (NOR). CONFIG_ETRAX_PTABLE_SECTOR is most
178 * likely the size of one flash block and "filesystem"-partition needs
179 * to be >=5 blocks to be able to use JFFS.
181 static struct mtd_partition axis_default_partitions[NUM_DEFAULT_PARTITIONS] = {
183 .name = "boot firmware",
184 .size = CONFIG_ETRAX_PTABLE_SECTOR,
185 .offset = 0
188 .name = "kernel",
189 .size = 10 * CONFIG_ETRAX_PTABLE_SECTOR,
190 .offset = CONFIG_ETRAX_PTABLE_SECTOR
192 #define FILESYSTEM_SECTOR (11 * CONFIG_ETRAX_PTABLE_SECTOR)
193 #ifdef CONFIG_ETRAX_NANDBOOT
195 .name = "rootfs",
196 .size = 10 * CONFIG_ETRAX_PTABLE_SECTOR,
197 .offset = FILESYSTEM_SECTOR
199 #undef FILESYSTEM_SECTOR
200 #define FILESYSTEM_SECTOR (21 * CONFIG_ETRAX_PTABLE_SECTOR)
201 #endif
203 .name = "rwfs",
204 .size = DEFAULT_MEDIA_SIZE - FILESYSTEM_SECTOR,
205 .offset = FILESYSTEM_SECTOR
209 #ifdef CONFIG_ETRAX_AXISFLASHMAP_MTD0WHOLE
210 /* Main flash device */
211 static struct mtd_partition main_partition = {
212 .name = "main",
213 .size = 0,
214 .offset = 0
216 #endif
218 /* Auxilliary partition if we find another flash */
219 static struct mtd_partition aux_partition = {
220 .name = "aux",
221 .size = 0,
222 .offset = 0
226 * Probe a chip select for AMD-compatible (JEDEC) or CFI-compatible flash
227 * chips in that order (because the amd_flash-driver is faster).
229 static struct mtd_info *probe_cs(struct map_info *map_cs)
231 struct mtd_info *mtd_cs = NULL;
233 printk(KERN_INFO
234 "%s: Probing a 0x%08lx bytes large window at 0x%08lx.\n",
235 map_cs->name, map_cs->size, map_cs->map_priv_1);
237 #ifdef CONFIG_MTD_CFI
238 mtd_cs = do_map_probe("cfi_probe", map_cs);
239 #endif
240 #ifdef CONFIG_MTD_JEDECPROBE
241 if (!mtd_cs)
242 mtd_cs = do_map_probe("jedec_probe", map_cs);
243 #endif
245 return mtd_cs;
249 * Probe each chip select individually for flash chips. If there are chips on
250 * both cse0 and cse1, the mtd_info structs will be concatenated to one struct
251 * so that MTD partitions can cross chip boundries.
253 * The only known restriction to how you can mount your chips is that each
254 * chip select must hold similar flash chips. But you need external hardware
255 * to do that anyway and you can put totally different chips on cse0 and cse1
256 * so it isn't really much of a restriction.
258 extern struct mtd_info* __init crisv32_nand_flash_probe (void);
259 static struct mtd_info *flash_probe(void)
261 struct mtd_info *mtd_cse0;
262 struct mtd_info *mtd_cse1;
263 struct mtd_info *mtd_total;
264 struct mtd_info *mtds[2];
265 int count = 0;
267 if ((mtd_cse0 = probe_cs(&map_cse0)) != NULL)
268 mtds[count++] = mtd_cse0;
269 if ((mtd_cse1 = probe_cs(&map_cse1)) != NULL)
270 mtds[count++] = mtd_cse1;
272 if (!mtd_cse0 && !mtd_cse1) {
273 /* No chip found. */
274 return NULL;
277 if (count > 1) {
278 #ifdef CONFIG_MTD_CONCAT
279 /* Since the concatenation layer adds a small overhead we
280 * could try to figure out if the chips in cse0 and cse1 are
281 * identical and reprobe the whole cse0+cse1 window. But since
282 * flash chips are slow, the overhead is relatively small.
283 * So we use the MTD concatenation layer instead of further
284 * complicating the probing procedure.
286 mtd_total = mtd_concat_create(mtds, count, "cse0+cse1");
287 #else
288 printk(KERN_ERR "%s and %s: Cannot concatenate due to kernel "
289 "(mis)configuration!\n", map_cse0.name, map_cse1.name);
290 mtd_toal = NULL;
291 #endif
292 if (!mtd_total) {
293 printk(KERN_ERR "%s and %s: Concatenation failed!\n",
294 map_cse0.name, map_cse1.name);
296 /* The best we can do now is to only use what we found
297 * at cse0. */
298 mtd_total = mtd_cse0;
299 map_destroy(mtd_cse1);
301 } else
302 mtd_total = mtd_cse0 ? mtd_cse0 : mtd_cse1;
304 return mtd_total;
308 * Probe the flash chip(s) and, if it succeeds, read the partition-table
309 * and register the partitions with MTD.
311 static int __init init_axis_flash(void)
313 struct mtd_info *main_mtd;
314 struct mtd_info *aux_mtd = NULL;
315 int err = 0;
316 int pidx = 0;
317 struct partitiontable_head *ptable_head = NULL;
318 struct partitiontable_entry *ptable;
319 int ptable_ok = 0;
320 static char page[PAGESIZE];
321 size_t len;
322 int ram_rootfs_partition = -1; /* -1 => no RAM rootfs partition */
323 int part;
325 /* We need a root fs. If it resides in RAM, we need to use an
326 * MTDRAM device, so it must be enabled in the kernel config,
327 * but its size must be configured as 0 so as not to conflict
328 * with our usage.
330 #if !defined(CONFIG_MTD_MTDRAM) || (CONFIG_MTDRAM_TOTAL_SIZE != 0) || (CONFIG_MTDRAM_ABS_POS != 0)
331 if (!romfs_in_flash && !nand_boot) {
332 printk(KERN_EMERG "axisflashmap: Cannot create an MTD RAM "
333 "device; configure CONFIG_MTD_MTDRAM with size = 0!\n");
334 panic("This kernel cannot boot from RAM!\n");
336 #endif
338 #ifndef CONFIG_ETRAX_VCS_SIM
339 main_mtd = flash_probe();
340 if (main_mtd)
341 printk(KERN_INFO "%s: 0x%08x bytes of NOR flash memory.\n",
342 main_mtd->name, main_mtd->size);
344 #ifdef CONFIG_ETRAX_NANDFLASH
345 aux_mtd = crisv32_nand_flash_probe();
346 if (aux_mtd)
347 printk(KERN_INFO "%s: 0x%08x bytes of NAND flash memory.\n",
348 aux_mtd->name, aux_mtd->size);
350 #ifdef CONFIG_ETRAX_NANDBOOT
352 struct mtd_info *tmp_mtd;
354 printk(KERN_INFO "axisflashmap: Set to boot from NAND flash, "
355 "making NAND flash primary device.\n");
356 tmp_mtd = main_mtd;
357 main_mtd = aux_mtd;
358 aux_mtd = tmp_mtd;
360 #endif /* CONFIG_ETRAX_NANDBOOT */
361 #endif /* CONFIG_ETRAX_NANDFLASH */
363 if (!main_mtd && !aux_mtd) {
364 /* There's no reason to use this module if no flash chip can
365 * be identified. Make sure that's understood.
367 printk(KERN_INFO "axisflashmap: Found no flash chip.\n");
370 #if 0 /* Dump flash memory so we can see what is going on */
371 if (main_mtd) {
372 int sectoraddr, i;
373 for (sectoraddr = 0; sectoraddr < 2*65536+4096;
374 sectoraddr += PAGESIZE) {
375 main_mtd->read(main_mtd, sectoraddr, PAGESIZE, &len,
376 page);
377 printk(KERN_INFO
378 "Sector at %d (length %d):\n",
379 sectoraddr, len);
380 for (i = 0; i < PAGESIZE; i += 16) {
381 printk(KERN_INFO
382 "%02x %02x %02x %02x "
383 "%02x %02x %02x %02x "
384 "%02x %02x %02x %02x "
385 "%02x %02x %02x %02x\n",
386 page[i] & 255, page[i+1] & 255,
387 page[i+2] & 255, page[i+3] & 255,
388 page[i+4] & 255, page[i+5] & 255,
389 page[i+6] & 255, page[i+7] & 255,
390 page[i+8] & 255, page[i+9] & 255,
391 page[i+10] & 255, page[i+11] & 255,
392 page[i+12] & 255, page[i+13] & 255,
393 page[i+14] & 255, page[i+15] & 255);
397 #endif
399 if (main_mtd) {
400 main_mtd->owner = THIS_MODULE;
401 axisflash_mtd = main_mtd;
403 loff_t ptable_sector = CONFIG_ETRAX_PTABLE_SECTOR;
405 /* First partition (rescue) is always set to the default. */
406 pidx++;
407 #ifdef CONFIG_ETRAX_NANDBOOT
408 /* We know where the partition table should be located,
409 * it will be in first good block after that.
411 int blockstat;
412 do {
413 blockstat = main_mtd->block_isbad(main_mtd,
414 ptable_sector);
415 if (blockstat < 0)
416 ptable_sector = 0; /* read error */
417 else if (blockstat)
418 ptable_sector += main_mtd->erasesize;
419 } while (blockstat && ptable_sector);
420 #endif
421 if (ptable_sector) {
422 main_mtd->read(main_mtd, ptable_sector, PAGESIZE,
423 &len, page);
424 ptable_head = &((struct partitiontable *) page)->head;
427 #if 0 /* Dump partition table so we can see what is going on */
428 printk(KERN_INFO
429 "axisflashmap: flash read %d bytes at 0x%08x, data: "
430 "%02x %02x %02x %02x %02x %02x %02x %02x\n",
431 len, CONFIG_ETRAX_PTABLE_SECTOR,
432 page[0] & 255, page[1] & 255,
433 page[2] & 255, page[3] & 255,
434 page[4] & 255, page[5] & 255,
435 page[6] & 255, page[7] & 255);
436 printk(KERN_INFO
437 "axisflashmap: partition table offset %d, data: "
438 "%02x %02x %02x %02x %02x %02x %02x %02x\n",
439 PARTITION_TABLE_OFFSET,
440 page[PARTITION_TABLE_OFFSET+0] & 255,
441 page[PARTITION_TABLE_OFFSET+1] & 255,
442 page[PARTITION_TABLE_OFFSET+2] & 255,
443 page[PARTITION_TABLE_OFFSET+3] & 255,
444 page[PARTITION_TABLE_OFFSET+4] & 255,
445 page[PARTITION_TABLE_OFFSET+5] & 255,
446 page[PARTITION_TABLE_OFFSET+6] & 255,
447 page[PARTITION_TABLE_OFFSET+7] & 255);
448 #endif
451 if (ptable_head && (ptable_head->magic == PARTITION_TABLE_MAGIC)
452 && (ptable_head->size <
453 (MAX_PARTITIONS * sizeof(struct partitiontable_entry) +
454 PARTITIONTABLE_END_MARKER_SIZE))
455 && (*(unsigned long*)((void*)ptable_head + sizeof(*ptable_head) +
456 ptable_head->size -
457 PARTITIONTABLE_END_MARKER_SIZE)
458 == PARTITIONTABLE_END_MARKER)) {
459 /* Looks like a start, sane length and end of a
460 * partition table, lets check csum etc.
462 struct partitiontable_entry *max_addr =
463 (struct partitiontable_entry *)
464 ((unsigned long)ptable_head + sizeof(*ptable_head) +
465 ptable_head->size);
466 unsigned long offset = CONFIG_ETRAX_PTABLE_SECTOR;
467 unsigned char *p;
468 unsigned long csum = 0;
470 ptable = (struct partitiontable_entry *)
471 ((unsigned long)ptable_head + sizeof(*ptable_head));
473 /* Lets be PARANOID, and check the checksum. */
474 p = (unsigned char*) ptable;
476 while (p <= (unsigned char*)max_addr) {
477 csum += *p++;
478 csum += *p++;
479 csum += *p++;
480 csum += *p++;
482 ptable_ok = (csum == ptable_head->checksum);
484 /* Read the entries and use/show the info. */
485 printk(KERN_INFO "axisflashmap: "
486 "Found a%s partition table at 0x%p-0x%p.\n",
487 (ptable_ok ? " valid" : "n invalid"), ptable_head,
488 max_addr);
490 /* We have found a working bootblock. Now read the
491 * partition table. Scan the table. It ends with 0xffffffff.
493 while (ptable_ok
494 && ptable->offset != PARTITIONTABLE_END_MARKER
495 && ptable < max_addr
496 && pidx < MAX_PARTITIONS - 1) {
498 axis_partitions[pidx].offset = offset + ptable->offset;
499 #ifdef CONFIG_ETRAX_NANDFLASH
500 if (main_mtd->type == MTD_NANDFLASH) {
501 axis_partitions[pidx].size =
502 (((ptable+1)->offset ==
503 PARTITIONTABLE_END_MARKER) ?
504 main_mtd->size :
505 ((ptable+1)->offset + offset)) -
506 (ptable->offset + offset);
508 } else
509 #endif /* CONFIG_ETRAX_NANDFLASH */
510 axis_partitions[pidx].size = ptable->size;
511 #ifdef CONFIG_ETRAX_NANDBOOT
512 /* Save partition number of jffs2 ro partition.
513 * Needed if RAM booting or root file system in RAM.
515 if (!nand_boot &&
516 ram_rootfs_partition < 0 && /* not already set */
517 ptable->type == PARTITION_TYPE_JFFS2 &&
518 (ptable->flags & PARTITION_FLAGS_READONLY_MASK) ==
519 PARTITION_FLAGS_READONLY)
520 ram_rootfs_partition = pidx;
521 #endif /* CONFIG_ETRAX_NANDBOOT */
522 pidx++;
523 ptable++;
527 /* Decide whether to use default partition table. */
528 /* Only use default table if we actually have a device (main_mtd) */
530 struct mtd_partition *partition = &axis_partitions[0];
531 if (main_mtd && !ptable_ok) {
532 memcpy(axis_partitions, axis_default_partitions,
533 sizeof(axis_default_partitions));
534 pidx = NUM_DEFAULT_PARTITIONS;
535 ram_rootfs_partition = DEFAULT_ROOTFS_PARTITION_NO;
538 /* Add artificial partitions for rootfs if necessary */
539 if (romfs_in_flash) {
540 /* rootfs is in directly accessible flash memory = NOR flash.
541 Add an overlapping device for the rootfs partition. */
542 printk(KERN_INFO "axisflashmap: Adding partition for "
543 "overlapping root file system image\n");
544 axis_partitions[pidx].size = romfs_length;
545 axis_partitions[pidx].offset = romfs_start - FLASH_CACHED_ADDR;
546 axis_partitions[pidx].name = "romfs";
547 axis_partitions[pidx].mask_flags |= MTD_WRITEABLE;
548 ram_rootfs_partition = -1;
549 pidx++;
550 } else if (romfs_length && !nand_boot) {
551 /* romfs exists in memory, but not in flash, so must be in RAM.
552 * Configure an MTDRAM partition. */
553 if (ram_rootfs_partition < 0) {
554 /* None set yet, put it at the end */
555 ram_rootfs_partition = pidx;
556 pidx++;
558 printk(KERN_INFO "axisflashmap: Adding partition for "
559 "root file system image in RAM\n");
560 axis_partitions[ram_rootfs_partition].size = romfs_length;
561 axis_partitions[ram_rootfs_partition].offset = romfs_start;
562 axis_partitions[ram_rootfs_partition].name = "romfs";
563 axis_partitions[ram_rootfs_partition].mask_flags |=
564 MTD_WRITEABLE;
567 #ifdef CONFIG_ETRAX_AXISFLASHMAP_MTD0WHOLE
568 if (main_mtd) {
569 main_partition.size = main_mtd->size;
570 err = add_mtd_partitions(main_mtd, &main_partition, 1);
571 if (err)
572 panic("axisflashmap: Could not initialize "
573 "partition for whole main mtd device!\n");
575 #endif
577 /* Now, register all partitions with mtd.
578 * We do this one at a time so we can slip in an MTDRAM device
579 * in the proper place if required. */
581 for (part = 0; part < pidx; part++) {
582 if (part == ram_rootfs_partition) {
583 /* add MTDRAM partition here */
584 struct mtd_info *mtd_ram;
586 mtd_ram = kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
587 if (!mtd_ram)
588 panic("axisflashmap: Couldn't allocate memory "
589 "for mtd_info!\n");
590 printk(KERN_INFO "axisflashmap: Adding RAM partition "
591 "for rootfs image.\n");
592 err = mtdram_init_device(mtd_ram,
593 (void *)partition[part].offset,
594 partition[part].size,
595 partition[part].name);
596 if (err)
597 panic("axisflashmap: Could not initialize "
598 "MTD RAM device!\n");
599 /* JFFS2 likes to have an erasesize. Keep potential
600 * JFFS2 rootfs happy by providing one. Since image
601 * was most likely created for main mtd, use that
602 * erasesize, if available. Otherwise, make a guess. */
603 mtd_ram->erasesize = (main_mtd ? main_mtd->erasesize :
604 CONFIG_ETRAX_PTABLE_SECTOR);
605 } else {
606 err = add_mtd_partitions(main_mtd, &partition[part], 1);
607 if (err)
608 panic("axisflashmap: Could not add mtd "
609 "partition %d\n", part);
612 #endif /* CONFIG_EXTRAX_VCS_SIM */
614 #ifdef CONFIG_ETRAX_VCS_SIM
615 /* For simulator, always use a RAM partition.
616 * The rootfs will be found after the kernel in RAM,
617 * with romfs_start and romfs_end indicating location and size.
619 struct mtd_info *mtd_ram;
621 mtd_ram = kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
622 if (!mtd_ram) {
623 panic("axisflashmap: Couldn't allocate memory for "
624 "mtd_info!\n");
627 printk(KERN_INFO "axisflashmap: Adding RAM partition for romfs, "
628 "at %u, size %u\n",
629 (unsigned) romfs_start, (unsigned) romfs_length);
631 err = mtdram_init_device(mtd_ram, (void *)romfs_start,
632 romfs_length, "romfs");
633 if (err) {
634 panic("axisflashmap: Could not initialize MTD RAM "
635 "device!\n");
637 #endif /* CONFIG_EXTRAX_VCS_SIM */
639 #ifndef CONFIG_ETRAX_VCS_SIM
640 if (aux_mtd) {
641 aux_partition.size = aux_mtd->size;
642 err = add_mtd_partitions(aux_mtd, &aux_partition, 1);
643 if (err)
644 panic("axisflashmap: Could not initialize "
645 "aux mtd device!\n");
648 #endif /* CONFIG_EXTRAX_VCS_SIM */
650 return err;
653 /* This adds the above to the kernels init-call chain. */
654 module_init(init_axis_flash);
656 EXPORT_SYMBOL(axisflash_mtd);