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

/*
 * $Id: redboot.c,v 1.21 2006/03/30 18:34:37 bjd Exp $
 *
 * Parse RedBoot-style Flash Image System (FIS) tables and
 * produce a Linux partition array to match.
 */

#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>

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,
                             struct mtd_partition **pparts,
                             unsigned long fis_origin)
{
	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 (master->block_isbad && 
		       master->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 (master->block_isbad && 
		       master->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 = master->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 (fis_origin) {
                        buf[i].flash_base -= fis_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 = {
	.owner = THIS_MODULE,
	.parse_fn = parse_redboot_partitions,
	.name = "RedBoot",
};

static int __init redboot_parser_init(void)
{
	return register_mtd_parser(&redboot_parser);
}

static void __exit redboot_parser_exit(void)
{
	deregister_mtd_parser(&redboot_parser);
}

module_init(redboot_parser_init);
module_exit(redboot_parser_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Red Hat, Inc. - David Woodhouse <dwmw2@cambridge.redhat.com>");
MODULE_DESCRIPTION("Parsing code for RedBoot Flash Image System (FIS) tables");
Commit	Line	Data
1da177e4	1	/*
b020bb7d	2	* $Id: redboot.c,v 1.21 2006/03/30 18:34:37 bjd Exp $
1da177e4 LT	3	*
	4	* Parse RedBoot-style Flash Image System (FIS) tables and
	5	* produce a Linux partition array to match.
	6	*/
	7
	8	#include <linux/kernel.h>
	9	#include <linux/slab.h>
	10	#include <linux/init.h>
	11	#include <linux/vmalloc.h>
	12
	13	#include <linux/mtd/mtd.h>
	14	#include <linux/mtd/partitions.h>
	15
	16	struct fis_image_desc {
	17	unsigned char name[16]; // Null terminated name
b020bb7d BD	18	uint32_t flash_base; // Address within FLASH of image
	19	uint32_t mem_base; // Address in memory where it executes
	20	uint32_t size; // Length of image
	21	uint32_t entry_point; // Execution entry point
	22	uint32_t data_length; // Length of actual data
	23	unsigned char _pad[256-(16+7*sizeof(uint32_t))];
	24	uint32_t desc_cksum; // Checksum over image descriptor
	25	uint32_t file_cksum; // Checksum over image data
1da177e4 LT	26	};
	27
	28	struct fis_list {
	29	struct fis_image_desc *img;
	30	struct fis_list *next;
	31	};
	32
	33	static int directory = CONFIG_MTD_REDBOOT_DIRECTORY_BLOCK;
	34	module_param(directory, int, 0);
	35
	36	static inline int redboot_checksum(struct fis_image_desc *img)
	37	{
	38	/* RedBoot doesn't actually write the desc_cksum field yet AFAICT */
	39	return 1;
	40	}
	41
97894cda	42	static int parse_redboot_partitions(struct mtd_info *master,
1da177e4 LT	43	struct mtd_partition **pparts,
	44	unsigned long fis_origin)
	45	{
	46	int nrparts = 0;
	47	struct fis_image_desc *buf;
	48	struct mtd_partition *parts;
	49	struct fis_list fl = NULL, tmp_fl;
	50	int ret, i;
	51	size_t retlen;
	52	char *names;
	53	char *nullname;
	54	int namelen = 0;
	55	int nulllen = 0;
	56	int numslots;
	57	unsigned long offset;
	58	#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	59	static char nullstring[] = "unallocated";
	60	#endif
	61
3c441baa DW	62	if ( directory < 0 ) {
	63	offset = master->size + directory * master->erasesize;
	64	while (master->block_isbad &&
	65	master->block_isbad(master, offset)) {
	66	if (!offset) {
	67	nogood:
	68	printk(KERN_NOTICE "Failed to find a non-bad block to check for RedBoot partition table\n");
	69	return -EIO;
	70	}
	71	offset -= master->erasesize;
	72	}
	73	} else {
	74	offset = directory * master->erasesize;
	75	while (master->block_isbad &&
	76	master->block_isbad(master, offset)) {
	77	offset += master->erasesize;
	78	if (offset == master->size)
	79	goto nogood;
	80	}
	81	}
1da177e4 LT	82	buf = vmalloc(master->erasesize);
	83
	84	if (!buf)
	85	return -ENOMEM;
	86
1da177e4 LT	87	printk(KERN_NOTICE "Searching for RedBoot partition table in %s at offset 0x%lx\n",
	88	master->name, offset);
	89
	90	ret = master->read(master, offset,
	91	master->erasesize, &retlen, (void *)buf);
	92
	93	if (ret)
	94	goto out;
	95
	96	if (retlen != master->erasesize) {
	97	ret = -EIO;
	98	goto out;
	99	}
	100
	101	numslots = (master->erasesize / sizeof(struct fis_image_desc));
	102	for (i = 0; i < numslots; i++) {
9cff3372 JB	103	if (!memcmp(buf[i].name, "FIS directory", 14)) {
	104	/* This is apparently the FIS directory entry for the
	105	* FIS directory itself. The FIS directory size is
77a33135	106	* one erase block; if the buf[i].size field is
9cff3372 JB	107	* swab32(erasesize) then we know we are looking at
9cff3372 JB	108	* a byte swapped FIS directory - swap all the entries!
77a33135	109	* (NOTE: this is 'size' not 'data_length'; size is
9cff3372 JB	110	* the full size of the entry.)
9cff3372 JB	111	*/
7ca353a4 DW	112
	113	/* RedBoot can combine the FIS directory and
	114	config partitions into a single eraseblock;
	115	we assume wrong-endian if either the swapped
	116	'size' matches the eraseblock size precisely,
	117	or if the swapped size actually fits in an
	118	eraseblock while the unswapped size doesn't. */
	119	if (swab32(buf[i].size) == master->erasesize \|\|
	120	(buf[i].size > master->erasesize
	121	&& swab32(buf[i].size) < master->erasesize)) {
9cff3372	122	int j;
11192146 RW	123	/* Update numslots based on actual FIS directory size */
11192146 RW	124	numslots = swab32(buf[i].size) / sizeof (struct fis_image_desc);
f33665d9 RW	125	for (j = 0; j < numslots; ++j) {
	126
	127	/* A single 0xff denotes a deleted entry.
	128	* Two of them in a row is the end of the table.
	129	*/
	130	if (buf[j].name[0] == 0xff) {
	131	if (buf[j].name[1] == 0xff) {
	132	break;
	133	} else {
	134	continue;
	135	}
	136	}
	137
9cff3372 JB	138	/* The unsigned long fields were written with the
	139	* wrong byte sex, name and pad have no byte sex.
	140	*/
77a33135 JB	141	swab32s(&buf[j].flash_base);
	142	swab32s(&buf[j].mem_base);
	143	swab32s(&buf[j].size);
	144	swab32s(&buf[j].entry_point);
	145	swab32s(&buf[j].data_length);
	146	swab32s(&buf[j].desc_cksum);
	147	swab32s(&buf[j].file_cksum);
9cff3372	148	}
7ca353a4	149	} else if (buf[i].size < master->erasesize) {
11192146 RW	150	/* Update numslots based on actual FIS directory size */
11192146 RW	151	numslots = buf[i].size / sizeof(struct fis_image_desc);
9cff3372	152	}
1da177e4	153	break;
9cff3372	154	}
1da177e4 LT	155	}
	156	if (i == numslots) {
	157	/* Didn't find it */
	158	printk(KERN_NOTICE "No RedBoot partition table detected in %s\n",
	159	master->name);
	160	ret = 0;
	161	goto out;
	162	}
	163
	164	for (i = 0; i < numslots; i++) {
	165	struct fis_list new_fl, *prev;
	166
f33665d9 RW	167	if (buf[i].name[0] == 0xff) {
	168	if (buf[i].name[1] == 0xff) {
	169	break;
	170	} else {
	171	continue;
	172	}
	173	}
1da177e4 LT	174	if (!redboot_checksum(&buf[i]))
	175	break;
	176
	177	new_fl = kmalloc(sizeof(struct fis_list), GFP_KERNEL);
	178	namelen += strlen(buf[i].name)+1;
	179	if (!new_fl) {
	180	ret = -ENOMEM;
	181	goto out;
	182	}
	183	new_fl->img = &buf[i];
	184	if (fis_origin) {
	185	buf[i].flash_base -= fis_origin;
	186	} else {
	187	buf[i].flash_base &= master->size-1;
	188	}
	189
	190	/* I'm sure the JFFS2 code has done me permanent damage.
	191	* I now think the following is _normal_
	192	*/
	193	prev = &fl;
	194	while(prev && (prev)->img->flash_base < new_fl->img->flash_base)
	195	prev = &(*prev)->next;
	196	new_fl->next = *prev;
	197	*prev = new_fl;
	198
	199	nrparts++;
	200	}
	201	#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	202	if (fl->img->flash_base) {
	203	nrparts++;
	204	nulllen = sizeof(nullstring);
	205	}
	206
	207	for (tmp_fl = fl; tmp_fl->next; tmp_fl = tmp_fl->next) {
	208	if (tmp_fl->img->flash_base + tmp_fl->img->size + master->erasesize <= tmp_fl->next->img->flash_base) {
	209	nrparts++;
	210	nulllen = sizeof(nullstring);
	211	}
	212	}
	213	#endif
95b93a0c	214	parts = kzalloc(sizeof(parts)nrparts + nulllen + namelen, GFP_KERNEL);
1da177e4 LT	215
	216	if (!parts) {
	217	ret = -ENOMEM;
	218	goto out;
	219	}
	220
1da177e4 LT	221	nullname = (char *)&parts[nrparts];
	222	#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	223	if (nulllen > 0) {
	224	strcpy(nullname, nullstring);
	225	}
	226	#endif
	227	names = nullname + nulllen;
	228
	229	i=0;
	230
	231	#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	232	if (fl->img->flash_base) {
	233	parts[0].name = nullname;
	234	parts[0].size = fl->img->flash_base;
	235	parts[0].offset = 0;
	236	i++;
	237	}
	238	#endif
	239	for ( ; i<nrparts; i++) {
	240	parts[i].size = fl->img->size;
	241	parts[i].offset = fl->img->flash_base;
	242	parts[i].name = names;
	243
	244	strcpy(names, fl->img->name);
	245	#ifdef CONFIG_MTD_REDBOOT_PARTS_READONLY
	246	if (!memcmp(names, "RedBoot", 8) \|\|
	247	!memcmp(names, "RedBoot config", 15) \|\|
	248	!memcmp(names, "FIS directory", 14)) {
	249	parts[i].mask_flags = MTD_WRITEABLE;
	250	}
	251	#endif
	252	names += strlen(names)+1;
	253
	254	#ifdef CONFIG_MTD_REDBOOT_PARTS_UNALLOCATED
	255	if(fl->next && fl->img->flash_base + fl->img->size + master->erasesize <= fl->next->img->flash_base) {
	256	i++;
	257	parts[i].offset = parts[i-1].size + parts[i-1].offset;
	258	parts[i].size = fl->next->img->flash_base - parts[i].offset;
	259	parts[i].name = nullname;
	260	}
	261	#endif
	262	tmp_fl = fl;
	263	fl = fl->next;
	264	kfree(tmp_fl);
	265	}
	266	ret = nrparts;
	267	*pparts = parts;
	268	out:
	269	while (fl) {
	270	struct fis_list *old = fl;
	271	fl = fl->next;
	272	kfree(old);
	273	}
	274	vfree(buf);
	275	return ret;
	276	}
	277
	278	static struct mtd_part_parser redboot_parser = {
	279	.owner = THIS_MODULE,
	280	.parse_fn = parse_redboot_partitions,
	281	.name = "RedBoot",
	282	};
	283
	284	static int __init redboot_parser_init(void)
285	{
286	return register_mtd_parser(&redboot_parser);
287	}
288
289	static void __exit redboot_parser_exit(void)
290	{
291	deregister_mtd_parser(&redboot_parser);
292	}
293
294	module_init(redboot_parser_init);
295	module_exit(redboot_parser_exit);
296
297	MODULE_LICENSE("GPL");
298	MODULE_AUTHOR("Red Hat, Inc. - David Woodhouse <dwmw2@cambridge.redhat.com>");
299	MODULE_DESCRIPTION("Parsing code for RedBoot Flash Image System (FIS) tables");