This is an old revision of
Flash from 2003-05-15 15:22:58.
This is a guide how to make use of your flash unit in the javastation.
Kernel support for the flash simm
Download the [patch|
http://www.dnd.utwente.nl/js/files/mtd-jsflash.diff] and patch the kernel.
Enable the following kernel options:
<![CDATA[* Memory Technology Device (MTD) support
* MTD partitioning support
* Caching block device access to MTD devices
* RAM/ROM/Flash chip drivers
** Detect flash chips by Common Flash Interface (CFI) probe
** Detect non-CFI AMD/JEDEC-compatible flash chips
** Support for AMD/Fujitsu flash chips
* Mapping drivers for chip access
** Sun Microsystems Javastation OS-flash support]]>
And it is also recommended to enable character device access. It is needed to erase the flash and install a kernel image.
<![CDATA[* Direct char device access to MTD devices]]>
Compile, reboot and you should see something like this:
<![CDATA[OS-flash: Found AMD AM29LV081
OS-flash: Found 4 x8 devices at 0x0 in 32-bit mode
OS-flash: Found 4 x8 devices at 0x400000 in 32-bit mode
OS-flash: Found an alias at 0x800000 for the chip at 0x400000
OS-flash: Found an alias at 0xc00000 for the chip at 0x0
number of JEDEC chips: 2
Creating 2 MTD partitions on "OS-flash":
0x00000000-0x00080000 : "Bootstrap"
0x00080000-0x00800000 : "Filesystem"]]>
Partitions
By default two partitions are created. This can be changed in drivers/mtd/maps/jsflash.c at line 120.
Filesystems
See [
WhichFilesystemForFlash] to choose your filesystem.
Booting from flash
I assume we are building our bootable image in /tmp/flash.
Kernel
Build
Target
Silo
Create an entry in etc/silo.conf in the image directory like this:
<![CDATA[image = /boot/vmlinux.gz
label=linux
proll=/boot/proll.img
append="root=/dev/mtdblock2"]]>
Image
Create a tree with the following under /tmp/flash:
<![CDATA[boot
boot/vmlinux.gz
boot/ieee32.b
boot/second.b
boot/proll.img
etc
etc/silo.conf]]>
Generate a bootable rom-image:
<![CDATA[# dd if=/dev/zero of=flash.img bs=1k count=1
# genromfs -a 512 -f romfs.img -d /tmp/flash
# cat romfs.img >> flash.img
# rm -f romfs.img
# losetup /dev/loop0 -o 1024 flash.img
# mount -t romfs -o ro /dev/loop0 /mnt
# silo -J flash.img -i /boot/ieee32.b -r /mnt
# umount /mnt
# losetup -d /dev/loop0]]>
Copy the image to the flash simm:
<![CDATA[# eraseall /dev/mtd/1
# cp flash.img /dev/mtd/1]]>
Done.
Jasper