I'm facing issue with booting the kernel from flash using JFF2 format.
I'm using the Linux kernel version 3.20.00.12 for the custom board using AM1705 with 32MB SDRAM and 8MB Atmel serial SPI dataflash AT45DB642D.
In the host system, I have created the JFFS image: block size 8KB (-e option) and page size = 1KB (-s option). This is as per the AT45DB642D datasheet.
host$ mkfs.jffs2 -lnp -e 8 -s 1024 -r target -o rootfs.jffs2
When I boot, from the u-boot, I receive the following error message:
JFFS2 version 2.2. (NAND) (SUMMARY) 2001-2006 Red Hat, Inc.
mtd_dataflash spi1.0: at45db642d (8192 KBytes) pagesize 1024 bytes, OTP
Creating 4 MTD partitions on "mtd_dataflash":
0x000000000000-0x000000020000 : "U-Boot"
0x000000020000-0x000000024000 : "U-Boot Environment"
0x000000024000-0x000000224000 : "Linux kernel"
0x000000224000-0x000000800000 : "Linux File system"
spi_davinci spi_davinci.1: Controller at 0xfee12000
JFFS2 write-buffering enabled buffer (1024) erasesize (8192)
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000000: 0xbd14 instead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000004: 0xc43e instead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000008: 0x58b5 instead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x0000000c: 0x6e08 instead
Further such events for this erase block will not be printed
Empty flash at 0x00000ffc ends at 0x00001000
Empty flash at 0x000017fc ends at 0x00001800
I suspect the issue to be in erase blocksize. B'cos when I execute the below command in NFS mode, (Instead of 8192 bytes, the erase block size is showing as 1024 bytes).
I receive the the output as
root@arago:/# cat /proc/mtd
dev: size erasesize name
mtd0: 00020000 00000400 "U-Boot"
mtd1: 00004000 00000400 "U-Boot Environment"
mtd2: 00200000 00000400 "Linux kernel"
mtd3: 005da000 00000400 "Linux File system"
I have been fiddling with this issue for the past 1 week. I really appreciate your help.
Regards,
Arul
Other observation, that I found while trying to read and write the partition via NFS mode is
1. Erase the filesystem partition:
root@arago:~# flash_eraseall /dev/mtd3
Erasing 1 Kibyte @ 5da000 -- 100 % complete.
2. Mount the partition and create a file.
root@arago:~# mkdir /mnt/flash
root@arago:~# mount -t jffs2 /dev/mtdblock3 /mnt/flash
JFFS2 write-buffering enabled buffer (1024) erasesize (8192)
root@arago:/# cd /mnt/flash
root@arago:/mnt/flash# ls
root@arago:/mnt/flash# cat ~/hello.c > hello.c
root@arago:/mnt/flash# cd ../..
root@arago:/# umount /mnt/flash
3. Reboot the target system
4. Again mount the partition
root@arago:~# mkdir /mnt/flash_new
root@arago:~# mount -t jffs2 /dev/mtdblock3 /mnt/flash_new
(Here I receive errors.....)
JFFS2 write-buffering enabled buffer (1024) erasesize (8192)
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000000: 0xfd33 instead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000004: 0x7ffe instead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000008: 0x3eb0 instead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x0000000c: 0x7fff instead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000010: 0xffff instead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000014: 0x77fe instead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000018: 0x0f3f instead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x0000001c: 0x73ff instead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000020: 0x77f6 instead
jffs2_scan_eraseblock(): Magic bitmask 0x1985 not found at 0x00000024: 0x7d7e instead
Further such events for this erase block will not be printed
Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes
empty_blocks 0, bad_blocks 0, c->nr_blocks 749
mount: /dev/mtdblock3: can't read superblock
