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Re: [DRAFT] resolving DFSG violations

On Mon, Oct 27, 2008 at 03:10, Neil Williams <codehelp@debian.org> wrote:

> I just want to find out: Under what circumstances does the blob need to
> be modified and who gets to do that modification?

Probably only the hardware engineers.

> Are these "chip manufacturer tools" physical tools/machines or software
> programs? (i.e. something I need to pick up in my hands or something I
> need to execute?)

kind of. Modern machines are designed on older machines using software
of some sort or another.

> Is there any way that someone else can use the same or
> similar tools to modify the blob (even if it is only useful to do so on
> a different board / with a different chipset)?

no, not usually unless you are the one that designed the board.

> If the chip is used on a different board with different configuration,

then you would generate your own firmware blob

> is the blob going to need to be changed and who gets to change it? Can

you as the board designer

> Debian include software that supports porting Debian to the new board or

thats where you write a gpl kernel driver

> can the blob be used to lock Debian out? If I build a customised board
> myself, is the blob / lack of blob going to prevent me running free
> software on the chip/board?

yes, if you don't load the blob into the chip, the chip stays
un-initialized. Thats what /lib/firmware is for.

You can put the blob on a flash chip in hardware to avoid software
needing to load it, but on cheap devices, the manufacturers are
usually trying to save on the cost of another chip.

> Sounds like a DRM type intervention.

no, that's something totally different. This firmware blob just tells
the chip what it's wires do (electriclly/logically)

> From an embedded perspective - so am I. I admit, I know very little
> about the minutiae of hardware but I know I'm going to come up against
> these problems and I want to know more about fixing them - *without*
> needing to get permission from the chip manufacturers or getting their
> software tools or needing expensive hardware tools.

If you what to change how the chip works outside of the device you
purchased you wouldn't be purchasing that device. For instance, you
aren't going to be able to take a usb/ethernet device and turn it into
a usb/sata device even if the chip was capable of it -- you'd have to
change the board layout so changing the firmware blob there doesn't
make any sense.

In any case, all of this is theoretical; it's just doesn't make any
sense to change the manufacturer firmware blob. If you want to do that
and are smart and experienced enough, you would start your own company
building hardware devices and compete with whatever device it is that
isn't doing what you need it to do. That would be much easier than
trying to change a chip/board you don't have schematics for.

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