[maemo-developers] closed stuff Re: 0xFFFF: GPL-licensed flasher for n770 and n800

[From: Frantisek Dufka]

Daniel Stone wrote:
> On Thu, Apr 12, 2007 at 06:59:55PM -0700, ext Carl Worth wrote:
>> On Sat, 7 Apr 2007 12:07:33 +0200, pancake wrote:
>>> The past week I released a gpl-licensed flasher for both Nokia
>>> Internet Tablets.
>> Fantastic!
>>
>> I've been very much looking forward to the time where there would be
>> instructions for downloading an entirely Free flasher and Free image
>> to flash to bring the unit into a bootable state from scratch.
>>
>> So this addresses an essential missing piece in that.
>>
>> What else might be missing?
> 
> Depends on what you mean by 'from scratch'.  If the unit does not have a
> bootloader _at all_, then you need to flash a bootloader via JTAG.  But
> that's mildly convoluted.
> 
>> What elements go into the Nokia fiasco image that cannot be built from
>> Free source?
> 
> The bootloaders (xloader, 2nd, secondary).

And the initfs too. Without it it is hard to initialize wi-fi nad bt 
chips properly.

> 
>> Of those, which must not be left out in order to have a bootable
>> device?

For beginning the most practical and easiest thing is to start with 
completely free rootfs and go down (initfs,bootloader) when you hit 
problems or have plenty of time.

Kernel is free to modify too but (closed) wi-fi modules depend on it so 
you can't deviate too much.

It looks like you also need to have bme running in your free solution 
for charging to work. At boot time you also need dsme but I guess/hope 
it can be killed once it does its job of letting initfs stuff work and 
you have replacement for the dsme part that keeps the HW watchdog happy. 
Killing it gives you control of display brightness and blanking.
What dsme manages can be guessed from names of libraries in
/mnt/initfs/usr/lib/dsme/

For list of critical closed stuff and some explanations check also 
discussion below
http://lwn.net/SubscriberLink/229838/6d98406660425a0e/

When you solve the practical problem of having the system running you 
will also have redistribution problem for closed parts which you still need.

Frantisek