[linux.git] / drivers / mtd / redboot.c

/*
 * Parse RedBoot-style Flash Image System (FIS) tables and
 * produce a Linux partition array to match.
 *
 * Copyright © 2001      Red Hat UK Limited
 * Copyright © 2001-2010 David Woodhouse <[email protected]>
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/vmalloc.h>

#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/module.h>

struct fis_image_desc {
    unsigned char name[16];      // Null terminated name
    uint32_t	  flash_base;    // Address within FLASH of image
    uint32_t	  mem_base;      // Address in memory where it executes
    uint32_t	  size;          // Length of image
    uint32_t	  entry_point;   // Execution entry point
    uint32_t	  data_length;   // Length of actual data
    unsigned char _pad[256-(16+7*sizeof(uint32_t))];
    uint32_t	  desc_cksum;    // Checksum over image descriptor
    uint32_t	  file_cksum;    // Checksum over image data
};

struct fis_list {
	struct fis_image_desc *img;
	struct fis_list *next;
};

static int directory = CONFIG_MTD_REDBOOT_DIRECTORY_BLOCK;
module_param(directory, int, 0);

static inline int redboot_checksum(struct fis_image_desc *img)
{
	/* RedBoot doesn't actually write the desc_cksum field yet AFAICT */
	return 1;
}

static int parse_redboot_partitions(struct mtd_info *master,
				    const struct mtd_partition **pparts,
				    struct mtd_part_parser_data *data)
{
	int nrparts = 0;
	struct fis_image_desc *buf;
	struct mtd_partition *parts;
	struct fis_list *fl = NULL, *tmp_fl;
	int ret, i;
	size_t retlen;
	char *names;
	char *nullname;
	int namelen = 0;
	int nulllen = 0;
	int numslots;
	unsigned long offset;
#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	static char nullstring[] = "unallocated";
#endif

	if ( directory < 0 ) {
		offset = master->size + directory * master->erasesize;
		while (mtd_block_isbad(master, offset)) {
			if (!offset) {
			nogood:
				printk(KERN_NOTICE "Failed to find a non-bad block to check for RedBoot partition table\n");
				return -EIO;
			}
			offset -= master->erasesize;
		}
	} else {
		offset = directory * master->erasesize;
		while (mtd_block_isbad(master, offset)) {
			offset += master->erasesize;
			if (offset == master->size)
				goto nogood;
		}
	}
	buf = vmalloc(master->erasesize);

	if (!buf)
		return -ENOMEM;

	printk(KERN_NOTICE "Searching for RedBoot partition table in %s at offset 0x%lx\n",
	       master->name, offset);

	ret = mtd_read(master, offset, master->erasesize, &retlen,
		       (void *)buf);

	if (ret)
		goto out;

	if (retlen != master->erasesize) {
		ret = -EIO;
		goto out;
	}

	numslots = (master->erasesize / sizeof(struct fis_image_desc));
	for (i = 0; i < numslots; i++) {
		if (!memcmp(buf[i].name, "FIS directory", 14)) {
			/* This is apparently the FIS directory entry for the
			 * FIS directory itself.  The FIS directory size is
			 * one erase block; if the buf[i].size field is
			 * swab32(erasesize) then we know we are looking at
			 * a byte swapped FIS directory - swap all the entries!
			 * (NOTE: this is 'size' not 'data_length'; size is
			 * the full size of the entry.)
			 */

			/* RedBoot can combine the FIS directory and
			   config partitions into a single eraseblock;
			   we assume wrong-endian if either the swapped
			   'size' matches the eraseblock size precisely,
			   or if the swapped size actually fits in an
			   eraseblock while the unswapped size doesn't. */
			if (swab32(buf[i].size) == master->erasesize ||
			    (buf[i].size > master->erasesize
			     && swab32(buf[i].size) < master->erasesize)) {
				int j;
				/* Update numslots based on actual FIS directory size */
				numslots = swab32(buf[i].size) / sizeof (struct fis_image_desc);
				for (j = 0; j < numslots; ++j) {

					/* A single 0xff denotes a deleted entry.
					 * Two of them in a row is the end of the table.
					 */
					if (buf[j].name[0] == 0xff) {
				  		if (buf[j].name[1] == 0xff) {
							break;
						} else {
							continue;
						}
					}

					/* The unsigned long fields were written with the
					 * wrong byte sex, name and pad have no byte sex.
					 */
					swab32s(&buf[j].flash_base);
					swab32s(&buf[j].mem_base);
					swab32s(&buf[j].size);
					swab32s(&buf[j].entry_point);
					swab32s(&buf[j].data_length);
					swab32s(&buf[j].desc_cksum);
					swab32s(&buf[j].file_cksum);
				}
			} else if (buf[i].size < master->erasesize) {
				/* Update numslots based on actual FIS directory size */
				numslots = buf[i].size / sizeof(struct fis_image_desc);
			}
			break;
		}
	}
	if (i == numslots) {
		/* Didn't find it */
		printk(KERN_NOTICE "No RedBoot partition table detected in %s\n",
		       master->name);
		ret = 0;
		goto out;
	}

	for (i = 0; i < numslots; i++) {
		struct fis_list *new_fl, **prev;

		if (buf[i].name[0] == 0xff) {
			if (buf[i].name[1] == 0xff) {
				break;
			} else {
				continue;
			}
		}
		if (!redboot_checksum(&buf[i]))
			break;

		new_fl = kmalloc(sizeof(struct fis_list), GFP_KERNEL);
		namelen += strlen(buf[i].name)+1;
		if (!new_fl) {
			ret = -ENOMEM;
			goto out;
		}
		new_fl->img = &buf[i];
		if (data && data->origin)
			buf[i].flash_base -= data->origin;
		else
			buf[i].flash_base &= master->size-1;

		/* I'm sure the JFFS2 code has done me permanent damage.
		 * I now think the following is _normal_
		 */
		prev = &fl;
		while(*prev && (*prev)->img->flash_base < new_fl->img->flash_base)
			prev = &(*prev)->next;
		new_fl->next = *prev;
		*prev = new_fl;

		nrparts++;
	}
#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	if (fl->img->flash_base) {
		nrparts++;
		nulllen = sizeof(nullstring);
	}

	for (tmp_fl = fl; tmp_fl->next; tmp_fl = tmp_fl->next) {
		if (tmp_fl->img->flash_base + tmp_fl->img->size + master->erasesize <= tmp_fl->next->img->flash_base) {
			nrparts++;
			nulllen = sizeof(nullstring);
		}
	}
#endif
	parts = kzalloc(sizeof(*parts)*nrparts + nulllen + namelen, GFP_KERNEL);

	if (!parts) {
		ret = -ENOMEM;
		goto out;
	}

	nullname = (char *)&parts[nrparts];
#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	if (nulllen > 0) {
		strcpy(nullname, nullstring);
	}
#endif
	names = nullname + nulllen;

	i=0;

#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	if (fl->img->flash_base) {
	       parts[0].name = nullname;
	       parts[0].size = fl->img->flash_base;
	       parts[0].offset = 0;
		i++;
	}
#endif
	for ( ; i<nrparts; i++) {
		parts[i].size = fl->img->size;
		parts[i].offset = fl->img->flash_base;
		parts[i].name = names;

		strcpy(names, fl->img->name);
#ifdef CONFIG_MTD_REDBOOT_PARTS_READONLY
		if (!memcmp(names, "RedBoot", 8) ||
				!memcmp(names, "RedBoot config", 15) ||
				!memcmp(names, "FIS directory", 14)) {
			parts[i].mask_flags = MTD_WRITEABLE;
		}
#endif
		names += strlen(names)+1;

#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
		if(fl->next && fl->img->flash_base + fl->img->size + master->erasesize <= fl->next->img->flash_base) {
			i++;
			parts[i].offset = parts[i-1].size + parts[i-1].offset;
			parts[i].size = fl->next->img->flash_base - parts[i].offset;
			parts[i].name = nullname;
		}
#endif
		tmp_fl = fl;
		fl = fl->next;
		kfree(tmp_fl);
	}
	ret = nrparts;
	*pparts = parts;
 out:
	while (fl) {
		struct fis_list *old = fl;
		fl = fl->next;
		kfree(old);
	}
	vfree(buf);
	return ret;
}

static struct mtd_part_parser redboot_parser = {
	.parse_fn = parse_redboot_partitions,
	.name = "RedBoot",
};
module_mtd_part_parser(redboot_parser);

/* mtd parsers will request the module by parser name */
MODULE_ALIAS("RedBoot");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("David Woodhouse <[email protected]>");
MODULE_DESCRIPTION("Parsing code for RedBoot Flash Image System (FIS) tables");
Commit	Line	Data
1da177e4	1	/*
1da177e4 LT	2	* Parse RedBoot-style Flash Image System (FIS) tables and
1da177e4 LT	3	* produce a Linux partition array to match.
a1452a37 DW	4	*
	5	* Copyright © 2001 Red Hat UK Limited
	6	* Copyright © 2001-2010 David Woodhouse <[email protected]>
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2 of the License, or
	11	* (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the Free Software
	20	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	21	*
1da177e4 LT	22	*/
	23
	24	#include <linux/kernel.h>
	25	#include <linux/slab.h>
	26	#include <linux/init.h>
	27	#include <linux/vmalloc.h>
	28
	29	#include <linux/mtd/mtd.h>
	30	#include <linux/mtd/partitions.h>
a0e5cc58	31	#include <linux/module.h>
1da177e4 LT	32
	33	struct fis_image_desc {
	34	unsigned char name[16]; // Null terminated name
b020bb7d BD	35	uint32_t flash_base; // Address within FLASH of image
	36	uint32_t mem_base; // Address in memory where it executes
	37	uint32_t size; // Length of image
	38	uint32_t entry_point; // Execution entry point
	39	uint32_t data_length; // Length of actual data
	40	unsigned char _pad[256-(16+7*sizeof(uint32_t))];
	41	uint32_t desc_cksum; // Checksum over image descriptor
	42	uint32_t file_cksum; // Checksum over image data
1da177e4 LT	43	};
	44
	45	struct fis_list {
	46	struct fis_image_desc *img;
	47	struct fis_list *next;
	48	};
	49
	50	static int directory = CONFIG_MTD_REDBOOT_DIRECTORY_BLOCK;
	51	module_param(directory, int, 0);
	52
	53	static inline int redboot_checksum(struct fis_image_desc *img)
	54	{
	55	/* RedBoot doesn't actually write the desc_cksum field yet AFAICT */
	56	return 1;
	57	}
	58
97894cda	59	static int parse_redboot_partitions(struct mtd_info *master,
b9adf469	60	const struct mtd_partition **pparts,
c7975330	61	struct mtd_part_parser_data *data)
1da177e4 LT	62	{
	63	int nrparts = 0;
	64	struct fis_image_desc *buf;
	65	struct mtd_partition *parts;
	66	struct fis_list fl = NULL, tmp_fl;
	67	int ret, i;
	68	size_t retlen;
	69	char *names;
	70	char *nullname;
	71	int namelen = 0;
	72	int nulllen = 0;
	73	int numslots;
	74	unsigned long offset;
	75	#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	76	static char nullstring[] = "unallocated";
	77	#endif
	78
3c441baa DW	79	if ( directory < 0 ) {
3c441baa DW	80	offset = master->size + directory * master->erasesize;
050c0c1b	81	while (mtd_block_isbad(master, offset)) {
3c441baa DW	82	if (!offset) {
	83	nogood:
	84	printk(KERN_NOTICE "Failed to find a non-bad block to check for RedBoot partition table\n");
	85	return -EIO;
	86	}
	87	offset -= master->erasesize;
	88	}
	89	} else {
	90	offset = directory * master->erasesize;
050c0c1b	91	while (mtd_block_isbad(master, offset)) {
3c441baa DW	92	offset += master->erasesize;
	93	if (offset == master->size)
	94	goto nogood;
	95	}
	96	}
1da177e4 LT	97	buf = vmalloc(master->erasesize);
	98
	99	if (!buf)
	100	return -ENOMEM;
	101
1da177e4 LT	102	printk(KERN_NOTICE "Searching for RedBoot partition table in %s at offset 0x%lx\n",
	103	master->name, offset);
	104
329ad399 AB	105	ret = mtd_read(master, offset, master->erasesize, &retlen,
329ad399 AB	106	(void *)buf);
1da177e4 LT	107
	108	if (ret)
	109	goto out;
	110
	111	if (retlen != master->erasesize) {
	112	ret = -EIO;
	113	goto out;
	114	}
	115
	116	numslots = (master->erasesize / sizeof(struct fis_image_desc));
	117	for (i = 0; i < numslots; i++) {
9cff3372 JB	118	if (!memcmp(buf[i].name, "FIS directory", 14)) {
	119	/* This is apparently the FIS directory entry for the
	120	* FIS directory itself. The FIS directory size is
77a33135	121	* one erase block; if the buf[i].size field is
9cff3372 JB	122	* swab32(erasesize) then we know we are looking at
9cff3372 JB	123	* a byte swapped FIS directory - swap all the entries!
77a33135	124	* (NOTE: this is 'size' not 'data_length'; size is
9cff3372 JB	125	* the full size of the entry.)
9cff3372 JB	126	*/
7ca353a4 DW	127
	128	/* RedBoot can combine the FIS directory and
	129	config partitions into a single eraseblock;
	130	we assume wrong-endian if either the swapped
	131	'size' matches the eraseblock size precisely,
	132	or if the swapped size actually fits in an
	133	eraseblock while the unswapped size doesn't. */
	134	if (swab32(buf[i].size) == master->erasesize \|\|
	135	(buf[i].size > master->erasesize
	136	&& swab32(buf[i].size) < master->erasesize)) {
9cff3372	137	int j;
11192146 RW	138	/* Update numslots based on actual FIS directory size */
11192146 RW	139	numslots = swab32(buf[i].size) / sizeof (struct fis_image_desc);
f33665d9 RW	140	for (j = 0; j < numslots; ++j) {
	141
	142	/* A single 0xff denotes a deleted entry.
	143	* Two of them in a row is the end of the table.
	144	*/
	145	if (buf[j].name[0] == 0xff) {
	146	if (buf[j].name[1] == 0xff) {
	147	break;
	148	} else {
	149	continue;
	150	}
	151	}
	152
9cff3372 JB	153	/* The unsigned long fields were written with the
	154	* wrong byte sex, name and pad have no byte sex.
	155	*/
77a33135 JB	156	swab32s(&buf[j].flash_base);
	157	swab32s(&buf[j].mem_base);
	158	swab32s(&buf[j].size);
	159	swab32s(&buf[j].entry_point);
	160	swab32s(&buf[j].data_length);
	161	swab32s(&buf[j].desc_cksum);
	162	swab32s(&buf[j].file_cksum);
9cff3372	163	}
7ca353a4	164	} else if (buf[i].size < master->erasesize) {
11192146 RW	165	/* Update numslots based on actual FIS directory size */
11192146 RW	166	numslots = buf[i].size / sizeof(struct fis_image_desc);
9cff3372	167	}
1da177e4	168	break;
9cff3372	169	}
1da177e4 LT	170	}
	171	if (i == numslots) {
	172	/* Didn't find it */
	173	printk(KERN_NOTICE "No RedBoot partition table detected in %s\n",
	174	master->name);
	175	ret = 0;
	176	goto out;
	177	}
	178
	179	for (i = 0; i < numslots; i++) {
	180	struct fis_list new_fl, *prev;
	181
f33665d9 RW	182	if (buf[i].name[0] == 0xff) {
	183	if (buf[i].name[1] == 0xff) {
	184	break;
	185	} else {
	186	continue;
	187	}
	188	}
1da177e4 LT	189	if (!redboot_checksum(&buf[i]))
	190	break;
	191
	192	new_fl = kmalloc(sizeof(struct fis_list), GFP_KERNEL);
	193	namelen += strlen(buf[i].name)+1;
	194	if (!new_fl) {
	195	ret = -ENOMEM;
	196	goto out;
	197	}
	198	new_fl->img = &buf[i];
c7975330 DB	199	if (data && data->origin)
	200	buf[i].flash_base -= data->origin;
	201	else
	202	buf[i].flash_base &= master->size-1;
1da177e4 LT	203
	204	/* I'm sure the JFFS2 code has done me permanent damage.
	205	* I now think the following is _normal_
	206	*/
	207	prev = &fl;
	208	while(prev && (prev)->img->flash_base < new_fl->img->flash_base)
	209	prev = &(*prev)->next;
	210	new_fl->next = *prev;
	211	*prev = new_fl;
	212
	213	nrparts++;
	214	}
	215	#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	216	if (fl->img->flash_base) {
	217	nrparts++;
	218	nulllen = sizeof(nullstring);
	219	}
	220
	221	for (tmp_fl = fl; tmp_fl->next; tmp_fl = tmp_fl->next) {
	222	if (tmp_fl->img->flash_base + tmp_fl->img->size + master->erasesize <= tmp_fl->next->img->flash_base) {
	223	nrparts++;
	224	nulllen = sizeof(nullstring);
	225	}
	226	}
	227	#endif
95b93a0c	228	parts = kzalloc(sizeof(parts)nrparts + nulllen + namelen, GFP_KERNEL);
1da177e4 LT	229
	230	if (!parts) {
	231	ret = -ENOMEM;
	232	goto out;
	233	}
	234
1da177e4 LT	235	nullname = (char *)&parts[nrparts];
	236	#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	237	if (nulllen > 0) {
	238	strcpy(nullname, nullstring);
	239	}
	240	#endif
	241	names = nullname + nulllen;
	242
	243	i=0;
	244
	245	#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	246	if (fl->img->flash_base) {
	247	parts[0].name = nullname;
	248	parts[0].size = fl->img->flash_base;
	249	parts[0].offset = 0;
	250	i++;
	251	}
	252	#endif
	253	for ( ; i<nrparts; i++) {
	254	parts[i].size = fl->img->size;
	255	parts[i].offset = fl->img->flash_base;
	256	parts[i].name = names;
	257
	258	strcpy(names, fl->img->name);
	259	#ifdef CONFIG_MTD_REDBOOT_PARTS_READONLY
	260	if (!memcmp(names, "RedBoot", 8) \|\|
	261	!memcmp(names, "RedBoot config", 15) \|\|
	262	!memcmp(names, "FIS directory", 14)) {
	263	parts[i].mask_flags = MTD_WRITEABLE;
	264	}
	265	#endif
	266	names += strlen(names)+1;
	267
	268	#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	269	if(fl->next && fl->img->flash_base + fl->img->size + master->erasesize <= fl->next->img->flash_base) {
	270	i++;
	271	parts[i].offset = parts[i-1].size + parts[i-1].offset;
	272	parts[i].size = fl->next->img->flash_base - parts[i].offset;
	273	parts[i].name = nullname;
	274	}
	275	#endif
	276	tmp_fl = fl;
	277	fl = fl->next;
	278	kfree(tmp_fl);
	279	}
	280	ret = nrparts;
	281	*pparts = parts;
	282	out:
	283	while (fl) {
	284	struct fis_list *old = fl;
	285	fl = fl->next;
	286	kfree(old);
	287	}
	288	vfree(buf);
	289	return ret;
	290	}
	291
	292	static struct mtd_part_parser redboot_parser = {
1da177e4 LT	293	.parse_fn = parse_redboot_partitions,
	294	.name = "RedBoot",
	295	};
b8f70bad	296	module_mtd_part_parser(redboot_parser);
1da177e4	297
d5de1907 AS	298	/* mtd parsers will request the module by parser name */
d5de1907 AS	299	MODULE_ALIAS("RedBoot");
1da177e4	300	MODULE_LICENSE("GPL");
44d1b980	301	MODULE_AUTHOR("David Woodhouse <[email protected]>");
1da177e4	302	MODULE_DESCRIPTION("Parsing code for RedBoot Flash Image System (FIS) tables");