1 /*
2  * Physical mapping layer for MTD using the Axis partitiontable format
3  *
4  * Copyright (c) 2001-2007 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  */
14 
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>
20 
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>
26 
27 #include <linux/cramfs_fs.h>
28 
29 #include <asm/axisflashmap.h>
30 #include <asm/mmu.h>
31 
32 #define MEM_CSE0_SIZE (0x04000000)
33 #define MEM_CSE1_SIZE (0x04000000)
34 
35 #define FLASH_UNCACHED_ADDR  KSEG_E
36 #define FLASH_CACHED_ADDR    KSEG_F
37 
38 #define PAGESIZE (512)
39 
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
47 
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 */
52 
53 struct partition_name {
54 	char name[6];
55 };
56 
57 /* The master mtd for the entire flash. */
58 struct mtd_info* axisflash_mtd = NULL;
59 
60 /* Map driver functions. */
61 
flash_read(struct map_info * map,unsigned long ofs)62 static map_word flash_read(struct map_info *map, unsigned long ofs)
63 {
64 	map_word tmp;
65 	tmp.x[0] = *(flash_data *)(map->map_priv_1 + ofs);
66 	return tmp;
67 }
68 
flash_copy_from(struct map_info * map,void * to,unsigned long from,ssize_t len)69 static void flash_copy_from(struct map_info *map, void *to,
70 			    unsigned long from, ssize_t len)
71 {
72 	memcpy(to, (void *)(map->map_priv_1 + from), len);
73 }
74 
flash_write(struct map_info * map,map_word d,unsigned long adr)75 static void flash_write(struct map_info *map, map_word d, unsigned long adr)
76 {
77 	*(flash_data *)(map->map_priv_1 + adr) = (flash_data)d.x[0];
78 }
79 
80 /*
81  * The map for chip select e0.
82  *
83  * We run into tricky coherence situations if we mix cached with uncached
84  * accesses to we only use the uncached version here.
85  *
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.
90  *
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.
94  */
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
103 };
104 
105 /*
106  * The map for chip select e1.
107  *
108  * If there was a gap between cse0 and cse1, map_priv_1 would get the wrong
109  * address, but there isn't.
110  */
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
119 };
120 
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
131 
132 #if (MAX_PARTITIONS < NUM_DEFAULT_PARTITIONS)
133 #error MAX_PARTITIONS must be >= than NUM_DEFAULT_PARTITIONS
134 #endif
135 
136 /* Initialize the ones normally used. */
137 static struct mtd_partition axis_partitions[MAX_PARTITIONS] = {
138 	{
139 		.name = "part0",
140 		.size = CONFIG_ETRAX_PTABLE_SECTOR,
141 		.offset = 0
142 	},
143 	{
144 		.name = "part1",
145 		.size = 0,
146 		.offset = 0
147 	},
148 	{
149 		.name = "part2",
150 		.size = 0,
151 		.offset = 0
152 	},
153 	{
154 		.name = "part3",
155 		.size = 0,
156 		.offset = 0
157 	},
158 	{
159 		.name = "part4",
160 		.size = 0,
161 		.offset = 0
162 	},
163 	{
164 		.name = "part5",
165 		.size = 0,
166 		.offset = 0
167 	},
168 	{
169 		.name = "part6",
170 		.size = 0,
171 		.offset = 0
172 	},
173 };
174 
175 
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.
180  */
181 static struct mtd_partition axis_default_partitions[NUM_DEFAULT_PARTITIONS] = {
182 	{
183 		.name = "boot firmware",
184 		.size = CONFIG_ETRAX_PTABLE_SECTOR,
185 		.offset = 0
186 	},
187 	{
188 		.name = "kernel",
189 		.size = 10 * CONFIG_ETRAX_PTABLE_SECTOR,
190 		.offset = CONFIG_ETRAX_PTABLE_SECTOR
191 	},
192 #define FILESYSTEM_SECTOR (11 * CONFIG_ETRAX_PTABLE_SECTOR)
193 #ifdef CONFIG_ETRAX_NANDBOOT
194 	{
195 		.name = "rootfs",
196 		.size = 10 * CONFIG_ETRAX_PTABLE_SECTOR,
197 		.offset = FILESYSTEM_SECTOR
198 	},
199 #undef FILESYSTEM_SECTOR
200 #define FILESYSTEM_SECTOR (21 * CONFIG_ETRAX_PTABLE_SECTOR)
201 #endif
202 	{
203 		.name = "rwfs",
204 		.size = DEFAULT_MEDIA_SIZE - FILESYSTEM_SECTOR,
205 		.offset = FILESYSTEM_SECTOR
206 	}
207 };
208 
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
215 };
216 #endif
217 
218 /* Auxiliary partition if we find another flash */
219 static struct mtd_partition aux_partition = {
220 	.name = "aux",
221 	.size = 0,
222 	.offset = 0
223 };
224 
225 /*
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).
228  */
probe_cs(struct map_info * map_cs)229 static struct mtd_info *probe_cs(struct map_info *map_cs)
230 {
231 	struct mtd_info *mtd_cs = NULL;
232 
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);
236 
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
244 
245 	return mtd_cs;
246 }
247 
248 /*
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.
252  *
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.
257  */
258 extern struct mtd_info* __init crisv32_nand_flash_probe (void);
flash_probe(void)259 static struct mtd_info *flash_probe(void)
260 {
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;
266 
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;
271 
272 	if (!mtd_cse0 && !mtd_cse1) {
273 		/* No chip found. */
274 		return NULL;
275 	}
276 
277 	if (count > 1) {
278 		/* Since the concatenation layer adds a small overhead we
279 		 * could try to figure out if the chips in cse0 and cse1 are
280 		 * identical and reprobe the whole cse0+cse1 window. But since
281 		 * flash chips are slow, the overhead is relatively small.
282 		 * So we use the MTD concatenation layer instead of further
283 		 * complicating the probing procedure.
284 		 */
285 		mtd_total = mtd_concat_create(mtds, count, "cse0+cse1");
286 		if (!mtd_total) {
287 			printk(KERN_ERR "%s and %s: Concatenation failed!\n",
288 				map_cse0.name, map_cse1.name);
289 
290 			/* The best we can do now is to only use what we found
291 			 * at cse0. */
292 			mtd_total = mtd_cse0;
293 			map_destroy(mtd_cse1);
294 		}
295 	} else
296 		mtd_total = mtd_cse0 ? mtd_cse0 : mtd_cse1;
297 
298 	return mtd_total;
299 }
300 
301 /*
302  * Probe the flash chip(s) and, if it succeeds, read the partition-table
303  * and register the partitions with MTD.
304  */
init_axis_flash(void)305 static int __init init_axis_flash(void)
306 {
307 	struct mtd_info *main_mtd;
308 	struct mtd_info *aux_mtd = NULL;
309 	int err = 0;
310 	int pidx = 0;
311 	struct partitiontable_head *ptable_head = NULL;
312 	struct partitiontable_entry *ptable;
313 	int ptable_ok = 0;
314 	static char page[PAGESIZE];
315 	size_t len;
316 	int ram_rootfs_partition = -1; /* -1 => no RAM rootfs partition */
317 	int part;
318 
319 	/* We need a root fs. If it resides in RAM, we need to use an
320 	 * MTDRAM device, so it must be enabled in the kernel config,
321 	 * but its size must be configured as 0 so as not to conflict
322 	 * with our usage.
323 	 */
324 #if !defined(CONFIG_MTD_MTDRAM) || (CONFIG_MTDRAM_TOTAL_SIZE != 0) || (CONFIG_MTDRAM_ABS_POS != 0)
325 	if (!romfs_in_flash && !nand_boot) {
326 		printk(KERN_EMERG "axisflashmap: Cannot create an MTD RAM "
327 		       "device; configure CONFIG_MTD_MTDRAM with size = 0!\n");
328 		panic("This kernel cannot boot from RAM!\n");
329 	}
330 #endif
331 
332 #ifndef CONFIG_ETRAX_VCS_SIM
333 	main_mtd = flash_probe();
334 	if (main_mtd)
335 		printk(KERN_INFO "%s: 0x%08x bytes of NOR flash memory.\n",
336 		       main_mtd->name, main_mtd->size);
337 
338 #ifdef CONFIG_ETRAX_NANDFLASH
339 	aux_mtd = crisv32_nand_flash_probe();
340 	if (aux_mtd)
341 		printk(KERN_INFO "%s: 0x%08x bytes of NAND flash memory.\n",
342 			aux_mtd->name, aux_mtd->size);
343 
344 #ifdef CONFIG_ETRAX_NANDBOOT
345 	{
346 		struct mtd_info *tmp_mtd;
347 
348 		printk(KERN_INFO "axisflashmap: Set to boot from NAND flash, "
349 		       "making NAND flash primary device.\n");
350 		tmp_mtd = main_mtd;
351 		main_mtd = aux_mtd;
352 		aux_mtd = tmp_mtd;
353 	}
354 #endif /* CONFIG_ETRAX_NANDBOOT */
355 #endif /* CONFIG_ETRAX_NANDFLASH */
356 
357 	if (!main_mtd && !aux_mtd) {
358 		/* There's no reason to use this module if no flash chip can
359 		 * be identified. Make sure that's understood.
360 		 */
361 		printk(KERN_INFO "axisflashmap: Found no flash chip.\n");
362 	}
363 
364 #if 0 /* Dump flash memory so we can see what is going on */
365 	if (main_mtd) {
366 		int sectoraddr, i;
367 		for (sectoraddr = 0; sectoraddr < 2*65536+4096;
368 				sectoraddr += PAGESIZE) {
369 			main_mtd->read(main_mtd, sectoraddr, PAGESIZE, &len,
370 				page);
371 			printk(KERN_INFO
372 			       "Sector at %d (length %d):\n",
373 			       sectoraddr, len);
374 			for (i = 0; i < PAGESIZE; i += 16) {
375 				printk(KERN_INFO
376 				       "%02x %02x %02x %02x "
377 				       "%02x %02x %02x %02x "
378 				       "%02x %02x %02x %02x "
379 				       "%02x %02x %02x %02x\n",
380 				       page[i] & 255, page[i+1] & 255,
381 				       page[i+2] & 255, page[i+3] & 255,
382 				       page[i+4] & 255, page[i+5] & 255,
383 				       page[i+6] & 255, page[i+7] & 255,
384 				       page[i+8] & 255, page[i+9] & 255,
385 				       page[i+10] & 255, page[i+11] & 255,
386 				       page[i+12] & 255, page[i+13] & 255,
387 				       page[i+14] & 255, page[i+15] & 255);
388 			}
389 		}
390 	}
391 #endif
392 
393 	if (main_mtd) {
394 		main_mtd->owner = THIS_MODULE;
395 		axisflash_mtd = main_mtd;
396 
397 		loff_t ptable_sector = CONFIG_ETRAX_PTABLE_SECTOR;
398 
399 		/* First partition (rescue) is always set to the default. */
400 		pidx++;
401 #ifdef CONFIG_ETRAX_NANDBOOT
402 		/* We know where the partition table should be located,
403 		 * it will be in first good block after that.
404 		 */
405 		int blockstat;
406 		do {
407 			blockstat = main_mtd->block_isbad(main_mtd,
408 				ptable_sector);
409 			if (blockstat < 0)
410 				ptable_sector = 0; /* read error */
411 			else if (blockstat)
412 				ptable_sector += main_mtd->erasesize;
413 		} while (blockstat && ptable_sector);
414 #endif
415 		if (ptable_sector) {
416 			main_mtd->read(main_mtd, ptable_sector, PAGESIZE,
417 				&len, page);
418 			ptable_head = &((struct partitiontable *) page)->head;
419 		}
420 
421 #if 0 /* Dump partition table so we can see what is going on */
422 		printk(KERN_INFO
423 		       "axisflashmap: flash read %d bytes at 0x%08x, data: "
424 		       "%02x %02x %02x %02x %02x %02x %02x %02x\n",
425 		       len, CONFIG_ETRAX_PTABLE_SECTOR,
426 		       page[0] & 255, page[1] & 255,
427 		       page[2] & 255, page[3] & 255,
428 		       page[4] & 255, page[5] & 255,
429 		       page[6] & 255, page[7] & 255);
430 		printk(KERN_INFO
431 		       "axisflashmap: partition table offset %d, data: "
432 		       "%02x %02x %02x %02x %02x %02x %02x %02x\n",
433 		       PARTITION_TABLE_OFFSET,
434 		       page[PARTITION_TABLE_OFFSET+0] & 255,
435 		       page[PARTITION_TABLE_OFFSET+1] & 255,
436 		       page[PARTITION_TABLE_OFFSET+2] & 255,
437 		       page[PARTITION_TABLE_OFFSET+3] & 255,
438 		       page[PARTITION_TABLE_OFFSET+4] & 255,
439 		       page[PARTITION_TABLE_OFFSET+5] & 255,
440 		       page[PARTITION_TABLE_OFFSET+6] & 255,
441 		       page[PARTITION_TABLE_OFFSET+7] & 255);
442 #endif
443 	}
444 
445 	if (ptable_head && (ptable_head->magic == PARTITION_TABLE_MAGIC)
446 	    && (ptable_head->size <
447 		(MAX_PARTITIONS * sizeof(struct partitiontable_entry) +
448 		PARTITIONTABLE_END_MARKER_SIZE))
449 	    && (*(unsigned long*)((void*)ptable_head + sizeof(*ptable_head) +
450 				  ptable_head->size -
451 				  PARTITIONTABLE_END_MARKER_SIZE)
452 		== PARTITIONTABLE_END_MARKER)) {
453 		/* Looks like a start, sane length and end of a
454 		 * partition table, lets check csum etc.
455 		 */
456 		struct partitiontable_entry *max_addr =
457 			(struct partitiontable_entry *)
458 			((unsigned long)ptable_head + sizeof(*ptable_head) +
459 			 ptable_head->size);
460 		unsigned long offset = CONFIG_ETRAX_PTABLE_SECTOR;
461 		unsigned char *p;
462 		unsigned long csum = 0;
463 
464 		ptable = (struct partitiontable_entry *)
465 			((unsigned long)ptable_head + sizeof(*ptable_head));
466 
467 		/* Lets be PARANOID, and check the checksum. */
468 		p = (unsigned char*) ptable;
469 
470 		while (p <= (unsigned char*)max_addr) {
471 			csum += *p++;
472 			csum += *p++;
473 			csum += *p++;
474 			csum += *p++;
475 		}
476 		ptable_ok = (csum == ptable_head->checksum);
477 
478 		/* Read the entries and use/show the info.  */
479 		printk(KERN_INFO "axisflashmap: "
480 		       "Found a%s partition table at 0x%p-0x%p.\n",
481 		       (ptable_ok ? " valid" : "n invalid"), ptable_head,
482 		       max_addr);
483 
484 		/* We have found a working bootblock.  Now read the
485 		 * partition table.  Scan the table.  It ends with 0xffffffff.
486 		 */
487 		while (ptable_ok
488 		       && ptable->offset != PARTITIONTABLE_END_MARKER
489 		       && ptable < max_addr
490 		       && pidx < MAX_PARTITIONS - 1) {
491 
492 			axis_partitions[pidx].offset = offset + ptable->offset;
493 #ifdef CONFIG_ETRAX_NANDFLASH
494 			if (main_mtd->type == MTD_NANDFLASH) {
495 				axis_partitions[pidx].size =
496 					(((ptable+1)->offset ==
497 					  PARTITIONTABLE_END_MARKER) ?
498 					  main_mtd->size :
499 					  ((ptable+1)->offset + offset)) -
500 					(ptable->offset + offset);
501 
502 			} else
503 #endif /* CONFIG_ETRAX_NANDFLASH */
504 				axis_partitions[pidx].size = ptable->size;
505 #ifdef CONFIG_ETRAX_NANDBOOT
506 			/* Save partition number of jffs2 ro partition.
507 			 * Needed if RAM booting or root file system in RAM.
508 			 */
509 			if (!nand_boot &&
510 			    ram_rootfs_partition < 0 && /* not already set */
511 			    ptable->type == PARTITION_TYPE_JFFS2 &&
512 			    (ptable->flags & PARTITION_FLAGS_READONLY_MASK) ==
513 				PARTITION_FLAGS_READONLY)
514 				ram_rootfs_partition = pidx;
515 #endif /* CONFIG_ETRAX_NANDBOOT */
516 			pidx++;
517 			ptable++;
518 		}
519 	}
520 
521 	/* Decide whether to use default partition table. */
522 	/* Only use default table if we actually have a device (main_mtd) */
523 
524 	struct mtd_partition *partition = &axis_partitions[0];
525 	if (main_mtd && !ptable_ok) {
526 		memcpy(axis_partitions, axis_default_partitions,
527 		       sizeof(axis_default_partitions));
528 		pidx = NUM_DEFAULT_PARTITIONS;
529 		ram_rootfs_partition = DEFAULT_ROOTFS_PARTITION_NO;
530 	}
531 
532 	/* Add artificial partitions for rootfs if necessary */
533 	if (romfs_in_flash) {
534 		/* rootfs is in directly accessible flash memory = NOR flash.
535 		   Add an overlapping device for the rootfs partition. */
536 		printk(KERN_INFO "axisflashmap: Adding partition for "
537 		       "overlapping root file system image\n");
538 		axis_partitions[pidx].size = romfs_length;
539 		axis_partitions[pidx].offset = romfs_start - FLASH_CACHED_ADDR;
540 		axis_partitions[pidx].name = "romfs";
541 		axis_partitions[pidx].mask_flags |= MTD_WRITEABLE;
542 		ram_rootfs_partition = -1;
543 		pidx++;
544 	} else if (romfs_length && !nand_boot) {
545 		/* romfs exists in memory, but not in flash, so must be in RAM.
546 		 * Configure an MTDRAM partition. */
547 		if (ram_rootfs_partition < 0) {
548 			/* None set yet, put it at the end */
549 			ram_rootfs_partition = pidx;
550 			pidx++;
551 		}
552 		printk(KERN_INFO "axisflashmap: Adding partition for "
553 		       "root file system image in RAM\n");
554 		axis_partitions[ram_rootfs_partition].size = romfs_length;
555 		axis_partitions[ram_rootfs_partition].offset = romfs_start;
556 		axis_partitions[ram_rootfs_partition].name = "romfs";
557 		axis_partitions[ram_rootfs_partition].mask_flags |=
558 			MTD_WRITEABLE;
559 	}
560 
561 #ifdef CONFIG_ETRAX_AXISFLASHMAP_MTD0WHOLE
562 	if (main_mtd) {
563 		main_partition.size = main_mtd->size;
564 		err = add_mtd_partitions(main_mtd, &main_partition, 1);
565 		if (err)
566 			panic("axisflashmap: Could not initialize "
567 			      "partition for whole main mtd device!\n");
568 	}
569 #endif
570 
571 	/* Now, register all partitions with mtd.
572 	 * We do this one at a time so we can slip in an MTDRAM device
573 	 * in the proper place if required. */
574 
575 	for (part = 0; part < pidx; part++) {
576 		if (part == ram_rootfs_partition) {
577 			/* add MTDRAM partition here */
578 			struct mtd_info *mtd_ram;
579 
580 			mtd_ram = kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
581 			if (!mtd_ram)
582 				panic("axisflashmap: Couldn't allocate memory "
583 				      "for mtd_info!\n");
584 			printk(KERN_INFO "axisflashmap: Adding RAM partition "
585 			       "for rootfs image.\n");
586 			err = mtdram_init_device(mtd_ram,
587 						 (void *)partition[part].offset,
588 						 partition[part].size,
589 						 partition[part].name);
590 			if (err)
591 				panic("axisflashmap: Could not initialize "
592 				      "MTD RAM device!\n");
593 			/* JFFS2 likes to have an erasesize. Keep potential
594 			 * JFFS2 rootfs happy by providing one. Since image
595 			 * was most likely created for main mtd, use that
596 			 * erasesize, if available. Otherwise, make a guess. */
597 			mtd_ram->erasesize = (main_mtd ? main_mtd->erasesize :
598 				CONFIG_ETRAX_PTABLE_SECTOR);
599 		} else {
600 			err = add_mtd_partitions(main_mtd, &partition[part], 1);
601 			if (err)
602 				panic("axisflashmap: Could not add mtd "
603 					"partition %d\n", part);
604 		}
605 	}
606 #endif /* CONFIG_EXTRAX_VCS_SIM */
607 
608 #ifdef CONFIG_ETRAX_VCS_SIM
609 	/* For simulator, always use a RAM partition.
610 	 * The rootfs will be found after the kernel in RAM,
611 	 * with romfs_start and romfs_end indicating location and size.
612 	 */
613 	struct mtd_info *mtd_ram;
614 
615 	mtd_ram = kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
616 	if (!mtd_ram) {
617 		panic("axisflashmap: Couldn't allocate memory for "
618 		      "mtd_info!\n");
619 	}
620 
621 	printk(KERN_INFO "axisflashmap: Adding RAM partition for romfs, "
622 	       "at %u, size %u\n",
623 	       (unsigned) romfs_start, (unsigned) romfs_length);
624 
625 	err = mtdram_init_device(mtd_ram, (void *)romfs_start,
626 				 romfs_length, "romfs");
627 	if (err) {
628 		panic("axisflashmap: Could not initialize MTD RAM "
629 		      "device!\n");
630 	}
631 #endif /* CONFIG_EXTRAX_VCS_SIM */
632 
633 #ifndef CONFIG_ETRAX_VCS_SIM
634 	if (aux_mtd) {
635 		aux_partition.size = aux_mtd->size;
636 		err = add_mtd_partitions(aux_mtd, &aux_partition, 1);
637 		if (err)
638 			panic("axisflashmap: Could not initialize "
639 			      "aux mtd device!\n");
640 
641 	}
642 #endif /* CONFIG_EXTRAX_VCS_SIM */
643 
644 	return err;
645 }
646 
647 /* This adds the above to the kernels init-call chain. */
648 module_init(init_axis_flash);
649 
650 EXPORT_SYMBOL(axisflash_mtd);
651