diff options
Diffstat (limited to 'packages/linux/nas100d-kernel/2.6.15/10-mtdpart-redboot-fis-byteswap.patch')
| -rw-r--r-- | packages/linux/nas100d-kernel/2.6.15/10-mtdpart-redboot-fis-byteswap.patch | 60 |
1 files changed, 43 insertions, 17 deletions
diff --git a/packages/linux/nas100d-kernel/2.6.15/10-mtdpart-redboot-fis-byteswap.patch b/packages/linux/nas100d-kernel/2.6.15/10-mtdpart-redboot-fis-byteswap.patch index edee083e3c..3fa0535abf 100644 --- a/packages/linux/nas100d-kernel/2.6.15/10-mtdpart-redboot-fis-byteswap.patch +++ b/packages/linux/nas100d-kernel/2.6.15/10-mtdpart-redboot-fis-byteswap.patch @@ -1,12 +1,38 @@ -On IXP4XX systems the FIS directory is big endian even with a little -endian kernel. This patch recognises the FIS directory on such a -system and byte swaps it to obtain a valid table based on the 'size' -field of the FIS directory (the size field is know to always match the -erase block size on such systems, and probably all systems.) +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. + +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> +Signed-off-by: Andrew Morton <akpm@osdl.org> +Modified slightly and +Signed-off-by: David Woodhouse <dwmw2@infradead.org> + +Index: drivers/mtd/redboot.c +=================================================================== +RCS file: /home/cvs/mtd/drivers/mtd/redboot.c,v +retrieving revision 1.18 +retrieving revision 1.19 +diff -u -p -r1.18 -r1.19 --- linux-2.6.15/drivers/mtd/redboot.c 1970-01-01 00:00:00.000000000 +0000 +++ linux-2.6.15/drivers/mtd/redboot.c 1970-01-01 00:00:00.000000000 +0000 -@@ -89,8 +89,34 @@ +@@ -89,8 +89,32 @@ static int parse_redboot_partitions(stru i = numslots; break; } @@ -14,10 +40,10 @@ erase block size on such systems, and probably all systems.) + 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 ++ * 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 ++ * (NOTE: this is 'size' not 'data_length'; size is + * the full size of the entry.) + */ + if (swab32(buf[i].size) == master->erasesize) { @@ -26,15 +52,13 @@ erase block size on such systems, and probably all systems.) + /* 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 ++ 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); + } + } break; @@ -42,3 +66,5 @@ erase block size on such systems, and probably all systems.) } if (i == numslots) { /* Didn't find it */ + + |