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Re: On the freeness of a BLOB-containing driver

On Dec 12, Bruce Perens <bruce@perens.com> wrote:

> What about the rest of the driver? I think that if you remove the BLOB, 
> it's Free Software. It talks to a bus interface, which is a natural 
> demarcation between our Free Software and the proprietary hardware 
> design. It loads an arbitrary firmware file into the device. The device 
> might not work without the BLOB, but the driver's still free as long as 
> it does not incorporate the BLOB.

> A good hardware design would put this code in FLASH on the board. If you 
Not really. A good designer would use permanent storage if the device
needs to be operational before the operating system is loaded, otherwise
uploading the firmware to RAM is usually the best choice.
The reason for this is not only the additional cost of the flash chip,
but also that (good) devices which use flash need to be more complex:
you would have to add a programming device, possibly a dual power supply
to drive it and you would need anyway some intelligent enough code on a
ROM to allow emergency recovery from bad flashing.
If flash is not used then you only need some dumb code which takes data
chunks from e.g. the USB port and copies them to RAM, which in this case
would probably be a standard function provided by the EZ-USB chip (or
function embedded in a single chip solution) which many devices use.

ciao, |
Marco | [9733 peekct3IX2ffY]

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