More pwlconfig stuff

[Adi Linden]

Hi,

> I wondered about that...I suppose including it is no problem (have to include
> the source also ?)

Under GPL the sources have to be available. I would imagine them being
part of the kernel source would be sufficient. Perhaps just indicate in
the README.pwlconfig where the sources for lxdialog can be found.

> Where I'm headed now, the device is specified in the configuration file
> deviceType="DOC" 
> deviceName="Disk-On-Chip"
> -or-
> deviceTYPE="FLASH"
> deviceName="Sandisk Flash Disk (IDE)"

Ok, there are several different possibilities in loading stuff into the
machine. You can simply use the flash like a HD. The disadvantage is that
with limited write cycles to the flash it has a predefined lifespan.

Then it's possible to create a ramdisk image. The ramdisk image on it's
own doesn't do much. It needs a kernel (seperate) and a bootloader, lilo
for an ext2 filesystem on flash, syslinux for a FAT filesystem on flash
and loadlin if the DOS operating system is on flash, too. The last one
wouldn't make sense but its on option (I don't care about supporting it
though).

If I am right, here are the steps required for each setup.

'Live' filesystem on flash (no ramdisk)
---------------------------------------
1. Erase the flash (IDE or DOC)
2. Make ext2 filesystem on flash
3. Copy the filesystem to flash
4. Run lilo (plilo for DOC, normal lilo for IDE FLASH)

Ramdisk with LILO
-----------------
1. Create ramdisk from filesystem (w/o kernel)
2. Make ext2 filesystem on FLASH or DOC
3. Copy necessary files to FLASH or DOC
    - Kernel
    - Ramdisk image
    - lilo & support files
4. Run lilo (plilo for DOC)

Ramdisk with SYSLINUX
---------------------
1. Create ramdisk from filesystem (w/o kernel)
2. Make FAT12 or FAT16 filesystem on FLASH or DOC
3. Install bootloader (syslinux)
4. Copy necessary files to FLASH or DOC
    - Kernel
    - Ramdisk image
    - syslinux.cfg

The above covers an original install. If you change the ramdisk image or
kernel the syslinux solution just shine. All you need to do is copy the
new kernel and/or ramdisk to the FLASH or DOC. That's it. No running lilo
or anything else!

The bootable CD is fairly easy. Unfortunaltely the 'easy' solution
requires a floppy image with MS-DOS 6.22 and CD-ROM drives. A tough
solution for anything but personal use. Thinking about it in retrospect it
might be an idea not to support it until we figure out how to do it
without MS-DOS.

The above solutions assume the FLASH or DOC is available on the running
development platform. In my case this doesn't work. I boot the target
system using a floppy and then ftp the files onto the target drive. 

So I think there needs to be an immediate step that allows you to create a
tar.gz archive, as an example, which contains everything to be transferred
to the target drive.

> where the Name is assigned by the user for their specific device.  So,
> I am building the menu items as follows:
> 
>        Erase $deviceName --->
>        Load File System onto $deviceName --->
>        Install LInux LOader (LILO) to $deviceName

If you're using a ramdisk system the above wouldn't work...

> For the ram disk, I was planning on including another line in the main menu
> (if the projectCompress parameter = "YES" )
> 
>       Configure Project File System --->
>       Compress FIle System -->
>       Extract File System for Project --->
>       ----
>
> Selecting Compress File System will allow you to specify which files are
> included in the compressed image and which ones get copied without change.
> Then when you select "Extract the file system image gets built and 
> then the compressed image gets made.

The ramdisk isn't just a tar file type of thing. The boot loader needs to
be configured to support a ramdisk of the desired size (My router does a
12MB ramdisk but the kernel default is 4MB max). Then the process of
creating the ramdisk determines the size of the ramdisk when it's loaded
into memory.

When I build the script for the router it was run like this:
   build_router [site] [ramdisk size] [ live | ramdisk | cd ]
This is a script for a very specific purpose, though and not what I am
planning now.

I just think doing the ramdisk business should be a choice of menus all on
its own. It's a process requiring different configurations options then
the 'live' filesystem approach.

So what I'll do is build the script to create the ramdisk. I'll email it
to you when it's done with usage instructions. I did want to use command
line switches, though. Still got to figure out how to do that without
requiring options to be passed in a specific order.

TTYL,
Adi

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