original_kernel/drivers/mtd/redboot.c

262 lines
6.6 KiB
C
Raw Normal View History

/*
* $Id: redboot.c,v 1.18 2005/11/07 11:14:21 gleixner 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
unsigned long flash_base; // Address within FLASH of image
unsigned long mem_base; // Address in memory where it executes
unsigned long size; // Length of image
unsigned long entry_point; // Execution entry point
unsigned long data_length; // Length of actual data
unsigned char _pad[256-(16+7*sizeof(unsigned long))];
unsigned long desc_cksum; // Checksum over image descriptor
unsigned long 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
buf = vmalloc(master->erasesize);
if (!buf)
return -ENOMEM;
if ( directory < 0 )
offset = master->size + directory*master->erasesize;
else
offset = directory*master->erasesize;
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 (buf[i].name[0] == 0xff) {
i = numslots;
break;
}
[PATCH] drivers/mtd/redboot.c: recognise a foreign byte sex partition table The RedBoot boot loader writes flash partition tables containing native byte sex 32 bit values. When booting an opposite byte sex kernel (e.g. an LE kernel from BE RedBoot) the current MTD driver fails to handle the partition table and therefore is unable to generate the correct partition map for the flash. So far as I am aware this problem is ARM specific, because only ARM supports software change of the CPU (memory system) byte sex, however the partition table parsing is in generic MTD code. The patch below has been tested on NSLU2 (an IXP4XX based system) with a patch, 10-ixp4xx-copy-from.patch (submitted to linux-arm-kernel - it's ARM specific) required to make the maps/ixp4xx.c driver work with an LE kernel. Builds of the patched system are in the 'unstable' release of OpenSlug and UcSlugC available from www.nslu2-linux.org. These builds are BE, the archives at www.nslu2-linux.org and www.handhelds.org (see monotone.vanille.de) can be built LE (currently DISTRO targets nslu-ltu.conf for LE thumb uclibc (32 bit kernel) and nslu2-lau.conf, nslu2-lag.conf for LE arm uclibc/glibc) and this patch has been tested extensively will both BE and LE systems on the NSLU2 (including swapping between BE and LE by reflashing from both RedBoot and Linux). The patch recognises that the FIS directory (the partition table) is byte-reversed by examining the partition table size, which is known to be one erase block (this is an assumption made elsewhere in redboot.c). If the size matches the erase block after byte swapping the value then byte-reversal is assumed, if not no further action is taken. The patched code is fail safe; should redboot.c be changed to support a partition table with a modified size field the test will fail and the partition table will be assumed to have the host byte sex. If byte-reversal is detected the patch byte swaps the remainder of the 32 bit fields in the copy of the table; this copy is then used to set up the MTD partition map. Signed-off-by: John Bowler <jbowler@acm.org> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Martin Michlmayr <tbm@cyrius.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-01 08:59:08 +08:00
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.)
*/
if (swab32(buf[i].size) == master->erasesize) {
int j;
for (j = 0; j < numslots && buf[j].name[0] != 0xff; ++j) {
/* The unsigned long fields were written with the
* wrong byte sex, name and pad have no byte sex.
*/
# define do_swab32(x) (x) = swab32(x)
do_swab32(buf[j].flash_base);
do_swab32(buf[j].mem_base);
do_swab32(buf[j].size);
do_swab32(buf[j].entry_point);
do_swab32(buf[j].data_length);
do_swab32(buf[j].desc_cksum);
do_swab32(buf[j].file_cksum);
# undef do_swab32
}
}
break;
[PATCH] drivers/mtd/redboot.c: recognise a foreign byte sex partition table The RedBoot boot loader writes flash partition tables containing native byte sex 32 bit values. When booting an opposite byte sex kernel (e.g. an LE kernel from BE RedBoot) the current MTD driver fails to handle the partition table and therefore is unable to generate the correct partition map for the flash. So far as I am aware this problem is ARM specific, because only ARM supports software change of the CPU (memory system) byte sex, however the partition table parsing is in generic MTD code. The patch below has been tested on NSLU2 (an IXP4XX based system) with a patch, 10-ixp4xx-copy-from.patch (submitted to linux-arm-kernel - it's ARM specific) required to make the maps/ixp4xx.c driver work with an LE kernel. Builds of the patched system are in the 'unstable' release of OpenSlug and UcSlugC available from www.nslu2-linux.org. These builds are BE, the archives at www.nslu2-linux.org and www.handhelds.org (see monotone.vanille.de) can be built LE (currently DISTRO targets nslu-ltu.conf for LE thumb uclibc (32 bit kernel) and nslu2-lau.conf, nslu2-lag.conf for LE arm uclibc/glibc) and this patch has been tested extensively will both BE and LE systems on the NSLU2 (including swapping between BE and LE by reflashing from both RedBoot and Linux). The patch recognises that the FIS directory (the partition table) is byte-reversed by examining the partition table size, which is known to be one erase block (this is an assumption made elsewhere in redboot.c). If the size matches the erase block after byte swapping the value then byte-reversal is assumed, if not no further action is taken. The patched code is fail safe; should redboot.c be changed to support a partition table with a modified size field the test will fail and the partition table will be assumed to have the host byte sex. If byte-reversal is detected the patch byte swaps the remainder of the 32 bit fields in the copy of the table; this copy is then used to set up the MTD partition map. Signed-off-by: John Bowler <jbowler@acm.org> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Martin Michlmayr <tbm@cyrius.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-01 08:59:08 +08:00
}
}
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)
break;
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 = kmalloc(sizeof(*parts)*nrparts + nulllen + namelen, GFP_KERNEL);
if (!parts) {
ret = -ENOMEM;
goto out;
}
memset(parts, 0, sizeof(*parts)*nrparts + nulllen + namelen);
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");